Mechanics and Materials Science

The following sections are included:

• Preface
• Editor
• Keynote Speaker
• Committee
• Table of Contents

To solve the problem of a mining triaxial heavy-duty dump’s putting rod ruptures prematurely, When the dump in the bending and twisting conditions, the push rod’s static strength and stiffness was analysed by Hypermesh, and get the modals shapes and modal frequencies and generated a frame MNF file (modal neutral file) from the Ansys, established the rigid - flexible coupling model of the frame in ADAMS, get a load time history of fully loaded front and rear suspension. According to material fatigue properties’ S-N curve of the frame, using of MSC. Fatigue software the frame’s life was analyzed. The result showed the position of minimum fatigue life of frame is consistent to the position of abnormal rupture of putting rod in actual use; in order to improve the design of heavy-duty dump truck provides a reference.

The slot plug is an important functional element for the technology of bottom-injection powder and greatly influences the operation of this technology. In order to improve the bottom injection efficiency, effects of the particle size on gas-powder flow distribution and pressures at outlet interface were investigated based on numerical simulation. The two-phase flow of N₂ and CaC₂ powder in a mixing chamber was described numerically and experimentally. The main goal of this paper was to explore the best particle size for obtaining perfect parameters of the bottom injection powder. The results reveal that when the particle size is 20 um, the pressure gradient is large in the chamber. And the powder can easily enter the slits due to velocities of gas powder in positive directions. The difference value of CaC₂ ratio between at the mixing chamber inlet and at the outlet is small. And the CaC₂ concentration distribution at the outlet interface is very uniform. When the diameters of particle size are other values, the difference values of CaC₂ ratio between at the mixing chamber inlet and at the outlet are great. The pressure gradient is large in the chamber and majority of velocities of gas powder move in negative directions, which are not conducive to gas-powder transmission into the slits of slot plug. The desulphurization efficiency in industrial trials is 15% greater than that obtained with the same type of top-powder process. Therefore, the particle size of 20 um would be better for the mixing chamber.

This paper to coiled tubing as the research object, considering coiled tubing drilling and milling bridge plug in the process of tubing and casing friction, fluid drag and lift and the bottom of the well drilling pressure and other affecting factors, establish the coiled tubing drilling and milling bridge plug force model. By using the energy method, the stress state analysis of the diameter and the bending section in the process of the coiled tubing drilling and grinding bridge is analyzed. According to the criterion of the limit depth of the drill string, the limit depth and the relationship between the limit depth and the pressure of the coiled tubing drilling and grinding bridge are established. Through the calculation of different friction coefficient and different drill bit pressure, with the increase of the friction coefficient and the bottom hole drilling pressure, the depth of the continuous oil pipe is gradually reduced.

Leak before break (LBB) is an important analysis method for insuring the structure safety and reliability of nuclear reactor. Now LBB technology is widely used in nuclear power plant design. It has a good development in foreign countries, but domestic research is relatively little. The study of crack propagation is core of LBB analysis. In this paper the LBB was analyzed for the pipes of the CEFR, which based on the A16 in RCC-MR. According to the analysis, the pipes we chose matched the LBB technique about the crack stability and the detecting of leak quantity, the time require from the beginning of the leak to the crack lose steady.

Drag reduction by grooves, as an easily realizable turbulent passive drag reduction technique and with the bionic structure and drag reduction mechanism similar to shark skin, becomes an important direction for research. In recent years, the research on drag reduction by grooves gradually shifts from two dimensional to three dimensional and begins to examine the impact of more complicated groove shapes. This paper conducts the numerical simulation of drag reduction by three dimensional groove surfaces, namely shark skin, the typical three dimensional groove surfaces. The RANS equations and RNG k-ε turbulence model are utilized for computation and analysis of the two three-dimensional features, U-grooves with attack angle and alternating configuration. The results show that the drag reduction by U-grooves with attack angle and alternating configuration performs worse than two dimensional U-grooves. For U-grooves with attack angle, the larger the attack angle, the less its drag reduction; for alternating U-grooves, the smaller the length of groove section, the worse its drag reduction. And different mechanisms exist for the impact of grooves with attack angle and alternating configuration.

For improving the expansion performance of trawl net in mid-water trawl productivity, a vertical cambered double fold-line otter boards was developed. A flume model experiment was conducted to measure the lift coefficient CL, drag coefficient CD and lift to drag ratio K in different angle of attack α. The experimental results are as follows: (1) The CL and K value show a trend of increasing at the beginning and then decreasing with the increase of angle of attack, CD value reflects an upward trend with the increase of angle of attack; (2) The Z2 otter board (front flow deflector angle was 27.5°) showed a better hydrodynamic performance. When α=30°, the max lift coefficient CLmax was 2.196, in this case CD =0.630, K=3.486. When α=15°, the max lift to drag ratio Kmax was 4.208, in this case CL =1.340, CD =0.318. Suggest the best working scope of angle of attack is between 15°~30°, in which case, CL>1.340 and K>3.486. The mean value of lift coefficient was 1.810 and the mean of lift to drag ratio was 3.968. Through comparative analysis of the hydrodynamic performance of different types of otter boards, the Z2 otter board both had good expansion performance and good expansion efficiency, which can provide a reference basis for further optimization of the pelagic trawl otter board.

A pitch bearing mechanical model is established according to the Hertz elastic contact theory that considers radial force, axial force and overturning moment. A typical MW wind turbine pitch bearings-double row four point contact ball slewing bearing is selected for numerical simulating, and radial clearance, groove radius of curvature coefficient, contact angle and double roller bearings spacing are discussed and analyzed. The simulation result indicates that the proper negative clearance can improve the bearing load-carrying capacity. The distributing law of optimum initial contact of different load bearing angle changes roughly the same, but the optimum initial contact curve drift along the longitudinal coordinate. The inner, outer race groove curvature radius has remarkable influence on the bearing performance. The optimal groove curvature radius exist that increase or decrease all may reduce the bearing capacity and increase the maximum contact force of the rolling body.

Crack in green compact has always been the important issue for a long time in powder metallurgy part industry. In this study, a modified Drucker-Prager Cap model validated in previous work has been evolved to research the metal powder compaction process including pressing, unloading and ejection stage with special consideration of cracking. A criterion for ductile damage from the equations of plasticity theory has been developed, and the damage threshold has been determined by compression failure experiment. The calculation of damage value has been implemented with user subroutines USDFLD in finite element code Abaqus. Meanwhile, the damage positions of different stages have been analyzed. The result has showed that the damage value during the ejection stage is much larger than the pressing stage, which will more easily lead to crack in compact.

For the need of anti-wind and anti-vibration in transmission line construction and maintenance work, the design of anti-galloping fitting based on PID automatic controlling theory was introduced in this paper. Performance of this PID closed loop adjustment control was revealed as simulation results in the computer-aided software. Receiving displacement in the line from sensors in line as input signal, PID controller would compare the dynamic displacement and static one, and give position signal to the motor. Two kinds of the anti-galloping fitting had been introduced in this paper, which could make the PID principles described earlier more practical and trusted.

Canned-motor pump is an absolute leak-free pump, widely used in the industry. By means of finite element analysis method, we can test the reliability of the pump body. We establish three-dimensional model of the pump body by means of Pro/engineer software. Under two different temperature conditions, we obtained the stress and deformation contours of pump body by ANSYS Workbench. The maximum stress and maximum deformation are comparisoned through table. The results show that the maximum stress and maximum deformation of the pump body are verified by the calculation and check of the pump body, which are less than the allowable stress of the material, and the pump body meets the strength requirement.

Stud with copulate threaded hole is the important part of the pressure vessel. Currently, in domestic field, safety checking of pressure vessel in a particular situation is still relatively lacking. To fill this gap, the author aims to establish a three-dimensional model of pressure vessel by UG software, using the ANSYS software to take finite element analysis on pressure vessel stud and the copulate threaded hole and then to compare it with theoretical results. Modeling and analysis methods mentioned in this paper have certain reference for similar structural analysis.

In the large water trawlers system work process, trawlers are influenced by the marine environment, and can produce significant movement, which seriously affect the drag efficiency. This study is based on the design of wave passive compensation device, establish a mathematical model for the simulation analysis, design the test process, extract and analyze the test data, finally compared with the theoretical analysis results and found that: Pressure of the accumulator change in cycle according to hoist’s cycle (caused by external disturbances), hoist’s displacement has different trend with the accumulator pressure. When the displacement amplitude is in less than 50 mm, pressure keep stable; Suffered the effect of inertia force, the speeds of pressure change in different stages. By the simulation analysis, the greater the charge pressure of accumulator in the equilibrium position, the greater pressure; the larger the accumulator’s area, the smaller the pressure.

Prestressed FRP reinforcement technology applied to the internal pressure pipeline repair, reinforcement project has been people's attention, Theoretical analysis and experimental study on the critical buckling of the steel tube reinforced with prestressed FRP have been conducted. The distribution of circumferential stress and radial stress of steel tube under prestress is studied, and got the extreme value of P_max1 based on the strength theory. Based on the shell theory, the extreme value of P_max2 under the condition of buckling theory is obtained. The theoretical results are consistent with the experimental results obtained in the paper. The critical condition of the buckling of the steel tube under the action of prestress was obtained by analyzing P_max1 and P_max2.

In terms of the speed control issues of proportional pump controlled motor system, this paper firstly analyzes the composition and working principle of the system, establishes the mathematical model of the system, and obtains the system characteristics. Then according to the characteristics of the system, this paper designs a new type of fuzzy PID structure, determines the fuzzy linguistic variables and membership functions, and formulates the fuzzy rules, determines the method of fuzzy reasoning and clarification. Finally, this paper carries out the simulation of the system in the MATLAB/Simulink environment, and analyzes system response curves of PID control and fuzzy PID control. The simulation results show that fuzzy PID control is better than conventional PID control on motor speed control.

An inclusion under uniform eigenstrains is of fundamental importance in composite mechanics. Although it is well known that an ellipse is the only inclusion shape which achieves a uniform internal stress field under anti-plane shear, it remains unclear what inclusion shapes achieve a polynomial internal stress field. The present paper studies an anti-plane inhomogeneous or homogeneous inclusion in an infinite elastic plane under uniform stress-free eigenstrains. The inclusion shape which gives a polynomial internal stress field is determined and the relation between the degree of the non-uniformity of the internal polynomial stress field and the inclusion’s geometrical shape is derived.

The past decade has witnessed the great development of super tall residential buildings in China. Optimal design is attracting interests due to the huge energy and material consumption. With the increase of height of modern super tall residential buildings, energy dissipation technologies are widely used to reduce the seismic responses of main structure. As an effective energy dissipation device, viscous damper (VD) can generate damping force by viscosity effects of the viscous liquid. Due to its velocity-dependent nature, viscous dampers can be applied to dissipate seismic energy under different earthquake levels, even frequent earthquake with small seismic responses. VD has been applied in super tall residential buildings, but the integrated optimization of primary structure due to the design redundancy caused by the installation of VD system is commonly not considered in current practices. In this paper, an integrated optimal design method is proposed to improve the stiffness performances through the application of VD system. The integrated optimization of primary structure is also considered in the proposed method. A 250-meter real super-tall residential building project is employed to illustrate the applicability and validity of the integrated optimal seismic performance design method.

The development of super tall steel residential buildings have drawn great attention due to prefabrication demand in building industry in recent years in China. Optimal design is attracting increasing interest due to the huge energy and material consumption for super tall steel structures. The optimization of certain structure is based on primitive design, which is commonly obtained by traditional design process. The design results obtained from the optimization of primitive design is called optimal design. Traditional optimal design method commonly starts with a primitive design which is greatly over constrained. The over constrained primitive design has great design redundancies, and further optimization process will successively reduce the design redundancies until the controlling constraints are properly contrained. There is another optimization process, however, which starts with a primitive design which is under constrained. The under constrained primitive design will be effectively upgraded in successive optimization process using minimum structural material increments until the controlling constraints are properly constrained. The first optimization process, which starts with over constrained primitive design is called forwardly constrained optimal design (FCOD) method. The second optimization process, which starts with under constrained primitive design is called reversely constrained optimal design (RCOD) method. The basis and process of RCOD method is thoroughly investigated in this study, and a 250-meter real super-tall steel structure is employed to illustrate the applicability and validity of the RCOD method.

Comparing with traditional brace, buckling-restrained brace (BRB) has better energy dissipation capacity and has been widely applied in tall residential buildings to dissipate energy and provide additional damping ratio. Due to its low yield strength properties, the BRBs are more energy-dissipative under medium earthquakes. In this paper, BRBs are installed in a tall residential building in high seismicity area to upgrade the seismic performance. And an integrated optimal design method was further introduced to optimize the primary structure utilizing the design redundancies induced by the installation of BRBs. A grid shear deformation (GSD) based optimal placement method developed by the authors was also introduced in this study to determine the optimum installation places of the BRBs. For the integrated optimal design of the primary structure, additional damping ratios related to different numbers of BRBs are firstly calculated under medium earthquake. The structural members of the primary structure are then to be optimized considering the design redundancies caused by different additional damping ratios. The optimal number of BRBs can finally be obtained from the relationship between the BRBs numbers and overall structural cost. A super tall residential building in high seismicity area is exemplified to show the effectiveness of the proposed integrated optimal method for buckling-restrained braces.

Though many automotive composite components and parts are being designed and manufactured to reduce the vehicle weight, cylinder helical composite springs are not yet widely used in automobile industry due, in part, to a lack of a fundamental understanding of its somewhat complex behavior. This paper is mainly about the analysis on the stiffness and strength of a type of cylinder helical composite spring whose spring wire has a hollow circular cross section and is made from fiber composite plies with ± 45° directions from the axis of the spring wire. At first, the manufacturing process of the composite springs is briefly introduced. Then, by combining the equivalent torsional shear modulus of fiber composite laminates with conventional stiffness formula of cylinder helical mental springs, the expression of the rigidity for the composite springs is proposed. At the same time, based on Tsai-Hill failure criterion and classical torsion theories of straight elastic rods, the ultimate compressive load and the maximum compressive displacement are also derived respectively. At last, compared with the results of a series of uniaxial compression tests, these theoretical results are very close to them.

This paper presents a12-bits differential successive approximation register ADC (SAR ADC). A calibration circuit is added to improve the accuracy reduction caused by mismatch. And a segmented capacitor array cascaded with a resister-string is adopted to reduce the layout area. The whole circuit design and layout are completed in this paper. The ADC occupies 0.54mm2 in a SMIC180nm technology and operates at 1.8V supply. The simulation results show that the Effective Number of Bits (ENOB) is 11.1 bits, the Signal to Noise and Distortion Ratio (SNDR) is 68.8dB and the Spurious Free Dynamic Range (SFDR) is 74.2dB for an input signal of 10 kHz and 1.2V peak-to-peak voltage with the clock frequency is 6.4MHz..

Establish a rigid flexible feed system device coupling virtual prototype model and calculate the pendulum strength. Using reticulated shell of the pendulum's finite element to establish the ANSYS model. Input finite element model to Adams to put the pendulum flexible through the interface; through the introduction of before and after pendulum model of quality information in contrast to verify the correctness of the import; under the most dangerous conditions and simulation of rigid flexible coupling model that pendulum and the maximum stress; import ADAMS load in ANSYS, recount the maximum stress of the pendulum body, and the relevant conclusions are drawn from the comparison of the two calculation results; use the the rigid flexible coupling model spectrum to gain several dangerous nodes as the basis for the calculation of fatigue.

Taking the hybrid electric vehicles with wheel motors as the research object, the building method of hardware-in-the-loop simulation platform was studied based on the ADVISOR backward simulation model. A forward simulation model of the vehicle based on Matlab/Simulink was built by adding driver model and modifying the backward simulation model. The control strategy model was turned into the vehicle controller by using Target Link, and a controlled object model was built based on the forward simulation model, then the hardware-in-the-loop simulation platform for hybrid electric vehicles with wheel motors was built and thrown into the hardware-in-the-loop simulation for testing the control strategy. The simulation results show that compared with the ADVISOR simulation results, the response was delayed by 1.8s, and the numerical was basically consistent. which indicates the effectiveness of the hardware- inthe- loop simulation platform, and provide important theory basis for the quick built of the hardware-in-the-loop simulation platform based on the backward simulation model.

Reducing the thinning ratio is very important to improve the stamping depth and structure efficiency of stamped aluminum alloy. The deep stamping processes of 5A06 aluminum alloy panels with continuous rectangular boxes were studied. The stamping process was modeled by finite element method. The influence of die radius, punch radius and lubrication on stamped panels was investigated and the effects of wrinkle, crack, wear and thinning ratio were taken into consideration.

FTS (Fast Tool Servo) has always been an important method for manufacturing nonaxisymmetric optical surface. In this paper, a novel tool path planning method is presented which plans tool path in two coordinate directions of a parallel structure 2 DOFs FTS simultaneously. Comparing with single DOF FTS, this method has significantly improved the ability of producing non-axisymmetric optical surface, such as slope surface.

By measuring the slag activity index and angle of repose, the effects of slag powder activity and angle of repose were studied on monomer of grinding aids MY-□, JS, molasses and LS et al. by single factor test method and orthogonal design test, and the industrial grinding test of grinding aids JS and MY-□ were introduced. Analysed the grinding aids composition influences on activity of slag powder and stability of material layer, and with comprehensive consideration of cost and performance reached an optimal solution: MY-□ is 0.02%, JS 0.03%, molasses 0.06%, LS 0.1%. The results show: MY-□ can obviously increase the activity of slag powder 15%, 19% respectively at 7d and 28d. JS can improve the output of slag grinding 10% by vertical mill. The vertical mill grinding aids can significantly improve the activity and output of slag powder.

An improved ant colony optimization (ACO) algorithm was presented in this paper, which aimed at the character of the explosion-proof mobile robot (EPMR) threedimensional (3D) path problem and the drawback of traditional ACO applied in the path planning. Firstly, the 3D abstract modeling was built for the wild environment. Then, traditional ACO was modified in the aspects of transition probability and updating pheromone mechanism. In the improved ACO, a new heuristic function was designed which depended on the synthetic influence of wild environment factors including wild terrain height, slope, and roughness. Meanwhile, the pheromone-updating mechanism was modified by utilizing pheromone trails on the shortest path to avoid stagnation of the search and improve convergence peed. Results of simulation experiments and performance analysis indicated the improved ACO can implement optimal 3D path planning in complex wild environment.

In this paper, the effect of the dilation angle of base cavity on the aerodynamic force of the projectile is investigated numerically. The distributions of the flow field parameters and the drag coefficient of projectile with different dilation shape base cavity were obtained. Numerical results show that the shape of the base cavity has a remarkably effective on the aerodynamic drag of the projectile. Smaller dilation angle of the base cavity is benefit to reduce the aerodynamic drug of the projectile. With the dilation angle of the base cavity increasing, the aerodynamic drag of the projectile increasing too.

Heavy haul tain with heavy axle load train is beneficial to improve transport efficiency. However, the overlarge wheelset lateral force will foce track lateral movement, even cause the accident of train derailment accident etc. Longitudinal impulse model is established in the natural system of coordinates, then the solving model of the wheelset lateral force is implemented, a 30,000 tons of 30 tons axle load heavy haul trains running on curve, the variation of the wheel and axle lateral force is simulated. Found that the magnitude of the coupler lateral force and centrifugal force have larger influence on the wheelset lateral force. The centrifugal foce if related to the running speed and the limiting train speed will be able to lower the lateral force of the wheelset. It is recommended that the running speed is limited below 80km/h for the train.

This paper puts forward a new to-and-fro guiding-yarn mechanism based on magnetic suspension driving which can avoid the friction and the error which the guiding leadsin order to increase the frequency of to-and-fro guiding-yarn and eliminate its friction force. The mathematical model is established for magnetic transmission to-and-fro guiding-yarn mechanism according to principle of magnetic force transmission, influence of magnetic distributing to magnetic circuit and theory of equivalent magnetic charge. Therefore, the forces of magnetic suspension and to-and-fro movement are varied with those parameters such as axial height, circuit distribution the air gap of active and passive magnetic pole and leakage coefficient. This new mechanism meets with the needs of high accuracy and high efficiency.

The real-time condition monitoring of complex equipment brings the problem of successive failure time estimation (FTE). Bayes is an updating technique which is frequently adopted in FTE. This paper discusses two iterative strategies for successive FTE based on parametric empirical Bayes (PEB). A simulation case is carried out to illustrate the performance of both strategies.

A new interactive 3D imaging equipment is designed. This display system uses a technique can merely reflect an image off of a surface to create an illusion of a 3D object floating in physical space. Range scans were captured using a Leap Motion sensor what can accurately identify the gesture. The design of this equipment was motivated by the lack of a 3d imaging equipment for the increasing number of gesture control equipment. When user’s hand moving in 3D space, the result can only be displayed in the 2D screen. Thus, the core idea behind the interactive 3d imaging equipment is to allow the user have an illusion of a 3D object floating in physical space, when using gesture control equipment. That will be more real feeling to the user. By this equipment we can do many things we can’t do it before.

In this study the vibration and oscillation of the flat head and the negative pressure head in thermal flying-height control (TFC) technology are investigated. The vibration and oscillation differential equations are established to analyze the dynamic characteristics of the headsconsidering the multi physical field coupling. And effects of the elastic coefficient of cantilever systemon the dynamic characteristics of the heads are obtained.

Cushion has a wide range of applications in engineering. It is a new attempt to use it in the field of printing and packaging lamination process. To further understand the effects of air cushion lamination in practical application, a kind of air cushion lamination experimental facility will be trial-manufactured, and a experimentally study would be made. All of the wind pressure, flow, thickness for cushion lamination experimental device could be adjusted, while simulation results on the air pressure distribution would be verified. The air pressure, the air cushion thickness and pressing time are adjustable. At the same time, the effects on air cushion pressure and lamination were tested. It is satisfactory for bonding effect while the supply pressure is 1000pa, cushion thickness is 2mm, and pressure time is 3mins. The adhesion test of corrugated board is satisfied. The analyses on the corrugated paper adhesive testing indicate that the bonding effect is satisfactory. The results show that the device can satisfy the experimental requirements of air cushion parameters and processing. Therefore it is feasible to air cushion lamination to be used for corrugated paper adhesive.

Based on the Sherief’s fractional order generalized thermoelasticity theory, a homogenous and isotropic elastic half space subjected to a thermal shock on the boundary of the elastic medium has been studied by employing Laplace transform and numerical inversion of Laplace transform algorithm. The distributions of nondimensional temperature, displacement and stress are obtained and illustrated graphically. The effects of fractional order parameters on the variations of different fields inside the medium are discussed.

The development of sewage sludge pyrolysis technology is helpful to achieve efficient, less cost and less polluting processing of sewage sludge, the output of which in China is very large. From the point of view of mass and energy balance, simulation of sewage sludge pyrolysis in equilibrium states was conducted. The effects of moisture and ash in sewage sludge and fixed carbon retention rate on reaction results were systematically discussed. The results were shown that yield and quality of gas and coke yield decreased with the increase of moisture in sewage sludge. With the increase of ash content, the coke yield increased the carbon content of coke decreased and the coke quality became poor. As the retention rate of fixed carbon increased from 50% to 100%, both coke yield and quality increased, the carbon content of coke rose from 11.69% to 20.93% and coke yield rose from 30.89% to 34.53%.

In this paper, a scheme of control of photovoltaic reactive power compensation is proposed. Using current sensor detect load current and the grid current, calculate the reactive power, and transport into the current regulator. After coordinate transformation in the DSP, controller gets the SVPWM control signals. Through the control signal to control the bidirectional PWM inverter switch tube open or closed, it Forms the required three-phase inverter voltage, and then complete the reactive power compensation.

To investigate the friction behavior of point contact operating, the friction tests were performed on a ball-on-disk rotating tribometer, which consisted of a rotating disk sliding under a bearing steel ball. The variation of friction coefficient and wearing capacity for the ball-on-disk pairs with different loading and velocity under 150# and 320# lubricant oil were presented combining with morphology of wear grooves. The result shown that the calculated point-contact stress from 2395MPa to 3379MPa for a wide range of operation conditions. Stribeck curves had the similar shape and only shifted depending strongly on viscosity of the lubricating oil. and the thickness of the surface oil film gradually increased with the rise of the velocity from 200 r/min to 1000r/min, and the mode of lubricant changed from boundary lubrication to mixed or hydrodynamic lubrication regime where slightly metal-metal contact occurs.

Through the analysis of fisheye lens imaging principle, sums up two kinds of method for the measure of target location based on fisheyes lens. One method using distortion correction to measure the target location, the other is not. This paper will respectively introduce the theory and the process of experiment, getting the more accuracy method when we comparing the date of experiment, and using it in the measure of target location.

Through analyzing and researching the reverse modeling methods, a kind of a reverse modeling method based on division of region was put forward, and the process and application fields of the reverse modeling method was also given. With the reverse modeling software Geomagic Design X as platform, the feasibility and advantage of the division of region reverse modeling method is verified through typical example, which provided a more effective and accurate solution for the parametric modeling based on reverse engineering.

Along with the fast development of the ocean exploitation, the cost-effective requirement of autonomous underwater vehicle (AUV), which can perform more complicated missions such as the oil exploitation and the inspection of the submarine pipeline is more urgent. Taper lock pin set is one of the most important units in submarine pipeline inspection AUV, its reliability and life affect directly on the reliability of AUVs employ. In general design of taper lock pin set, a lot of uncertainties affect its reliability. In this paper, reliability-based design optimization (RBDO) is proposed to handle the taper lock pin set design under two types uncertainties and first-order reliability method (FORM) is used to calculate reliability of the its performance functions. Finally, an engineering example is used to illustrate the proposed model to taper lock pin for submarine pipeline inspection AUV.

In this paper, the AMEsim simulation model of the emergency valve is built, and the performance of the valve is simulated and analyzed according to the structure of double circuit hydraulic steering system, the optimal structural parameters of the performance of the emergency valve are studied. In the end, the performance of the emergency valve is verified by the test, which provide theoretical basis and technical data support for product design.

We know the soldering of SMT be asked lead-free. On July 1, 2006 RoHS came into effect in most consumer electronics produced in the EU. Because RoHS and green manufacturing developed, people thought another connect technology----Conductive adhesive bonding technology. An electrically conductive adhesive is a glue that is primarily used for electronics. The paper introduced the Conductive adhesive Conduction principle mainly. And describing the application of Conductive adhesive technology. Such as Adhesive bonding and Flex circuits. I hope people should study the problems that conductive adhesive bonding instead of soldering continuously.

IGBT device has been widely used in the power industry, its level of quality and reliability has important significance for the development of the industry. The single-tube IGBT was as the test object and its main static parameters, output characteristics and capacitance testing principles and methods were analyzed. The experimental data and waveform was obtained by Keysight tester. The results show effectiveness of the proposed test method. The results can provide a reference for module selection.

The drum is the key part of the winch. The mechanical model of drum was established in this paper, according to the actual working condition of the winch to determine the load form and the stress analysis was carried out. The calculation results were analyzed, and the drum structure was further optimized to improve. The paper provides a reference method for design of large winch drum to meet the working performance and the quality of the drum was effectively reduced.

The thermal design of integrated electronic system is a technical problem which ASM weapon is facing and urgent to handle with. In this article, we first describe the specific content of thermal design, and then analyze the internal and external thermal environment of integrated electronic equipment on ASM. After that, the methods of thermal design for ASM integrated electronic equipment are given. Lastly, we use the power nodule, one part of integrate electronic equipment with biggest heat, to make an thermal simulation analysis example, and verify the reasonability of power module thermal design by comparing with measured temperature, what could provide a reference for the thermal design thermal and simulation of ASM integrated electronic devices.

High-altitude long-endurance UAV is a new unmanned aerial vehicle. In battlefield reconnaissance and high-altitude atmospheric sounding and so on has its special uses. According to the characteristic of UAV, joined-wing aerodynamic configuration is constructed. Through modeling, meshing, numerical calculation and matlab software simulation, vortex lattice method is applied to analyze the UAV lift-drag characteristics, longitudinal static stability and lateral and directional static stability. The calculation results fulfill design objectives and which can provide theoretical basis for large-scale UAV conceptual and preliminary design.

The multi-objective and constrained nonlinearly optimal model to realize the high efficiency and less mass design of the multi-stage gear transmission system has been established, the universal expression of design variables, objective functions, and constraints have been also derived. The proposed optimization theory integrated NSGA-II algorithm is feasible and reliable by applying for some optimal examples of space gear transmission system. The results have shown the theory proposed can realize the multiconception design of the space multi-stage gear transmission system, and is an effective designing and decision-making tool in the field of the space gear transmission system.

In this paper, a new type of five legged bionic robot is designed, which has the characteristics of high stability, strong carrying capacity, convenient and quick moving and so on. Firstly, the mechanism design of five legged bionic robot is introduced and the three-dimensional model of the five legged robot is built. In this paper, the analysis from two aspects of the single leg and the overall mechanism is carried on. Then, the kinematics of the robot single leg is analyzed.

ITO conductive glass is on the basis of sodium calcium or silicon boron based glass, using the method of magnetron sputtering plating a layer of indium tin oxide (commonly known as ITO) film processing. In this paper, by using RF magnetron sputtering method to change the sputtering power, argon oxygen ratio and sputtering time, the electrochromic materials——WO₃ were prepared in different conditions. Under the best conditions (O₂: Ar=9:21, Power=90W, Pressure=1.4Pa, Time=1h), the transmittance of WO₃ thin film of the colored and faded states in the visible light region is more than 80%, and the film has a very good cycle property.

Taking an electric vehicle as the research object, based on the MATLAB established the pure electric vehicle power system components and vehicle simulation model. The transmission parameters as the optimized goal, in ISIGHT, the response surface method is used to construct the design variables and the optimized target approximation model. The genetic algorithm is used to optimize the parameters of the powertrain of the vehicle. Analysis and comparison of the dynamic performance and economic simulation of the vehicle before and after optimization. The results show that under the condition of satisfying the vehicle dynamic design target, the optimization of the vehicle driving range increased by 20.1% in the NEDC driving conditions.

A kind of bio-inspired lightweight sandwich structure was designed based on the microstructure of the cross section of the beetle elytra. The traditional lightweight honeycomb sandwich structure was used to compare with the new structure. Samples of the two structures were manufactured by 3D printing technology. The mechanical properties of the lightweight structures were analyzed by finite element method (FEM). Besides, the three points bending tests of the samples were carried out with universal testing machine. Comparing the results of FEM analysis and experiments, it turned out that the results were consistent with each other and the effectiveness of the FEM analysis was proved. Also, the superiorities of the bio-inspired sandwich structure were showed through the analysis. Additionally, the unit cell of the lightweight bio-inspired sandwich structure was optimized based on response surface analysis, which eventually reduced weight of the unit cell of the structure further on basis of meeting the requirements of strength, realized lightweight design and established base for applications.

Based on theories of fluid dynamics, numerical simulation method was implemented on analysis on the cleaning performance of filter bag section of cleaning system in bag filter, using a two-dimensional, compressible and unsteady flow mathematical model. The impacts of related factors which include different injection pressure, nozzle diameter, injection distance and filter bag length on unsteady flow field distribution in filter bag were discovered, based on the response surface methodology (RSM) and using statistical software Design-expert. The quadratic polynomial prediction model of the four impact factors was developed by variance analysis method and significant examination of regression equation coefficients and the model was revised as the theoretical guidance for the optimization of cleaning system. The results showed that: The peak pressure of the bag wall was significantly influenced by the injection pressure and the greater the value of injection pressure, the greater the peak pressure value of the bag wall. Bag wall peak pressure was increased with the increase of the diameter of nozzle, but the rate of growth was reduced. The bag wall peak pressure was decreased with the increase of the length of the filter bag. The peak pressure of the bag wall was not significantly affected by the injection distance, and its value was slightly reduced with increase of the injection distance. Within the study range, the effect of dust-cleaning was optimal and the conclusion was extremely useful in improving the cleaning performance of the bag filter.

A multi-rigid-body dynamic model of crank-rod mechanism was built up through ADAMS to achieve strength analysis of a connecting rod of gasoline engine under special operating conditions. The difference between simulation results and theoretical calculating results of maximum compressive force and maximum tensile force acting on connecting rod for a complete cycle was less than 5%, which indicates the validity of the simulation methodology. Finite element analysis was done to calculate stresses under maximum compressive and tensile loading, the loads and boundary conditions obtained from dynamic simulation. The presented results indicates the connecting rod met the strength requirement, for the minimum factor of safety at critical area near the transition to the pin end is 2.01 higher than the maximum required factor of 1.2.

Plastic film is widely used in modern packaging, and its heat sealing quality directly affects the quality of packaging products, but also affects the performance of packaging machinery. This paper focuses on the temperature control of plastic film heat sealing, gives some theoretical analysis based on the fuzzy PID, and carries out computer simulation that has a certain engineering application value.

Laser cladding of Fe-based alloy on wheel/rail materials is conducted by YLC-I LCD laser in order to explore the effect of laser cladding treatment on rolling contact wear and damage behaviors of Fe-coated new high-speed wheel/rail steels using a GPM-30 microcomputer control rolling contact fatigue tester. The results indicate that uniform and compact cladding coating without stomata and cracks and with the thickness of about 1mm is obtained. A white band can be observed around bonding region between cladding layer and heat-affected zone, which shows an excellent metallurgical bonding with the substrate is obtained. There are two crystallization morphologies of dendrites and eutectic in cladding zone. The micro-hardness of laser cladding layer of wheel and rail specimens respectively increase 88.3% and 123.1% compared with untreated wheel/rail materials. The wear loss of wheel/rail without laser cladding is 1.8 times as much as treated wheel/rail materials and the wear mechanism is mainly serious fatigue. The fatigue resistance of laser cladding wheel/rail materials is enhanced remarkably and the main wear mechanism is slight adhesion wear and fatigue wear.

This paper designs a three-phase asynchronous motor soft starter based on dsPIC30F6014A microcontroller. Completed the soft starter based on dsPIC30F6014A microcontroller is the hardware design and software design. And for the design of the soft starter has carried on the simulation analysis. Simulation results show that the soft starter effective reduce the starting current of three-phase asynchronous motor, achieve a variety of load security and protect the motor.

Inductively coupled plasma source (ICP), as a good atomization source, ionization source and the excitation source, is often used as atomic emission spectral analysis of excitation light source. It has a wide range of applications in environmental science, material science, life science, geological analysis, metallurgical analysis and other fields. This paper elaborated ICP source structure, the influencing factors on the performance and operating principle, separately. Finally, the daily maintenance measures about ICP were summarized and its applications were prospected, such as ICP-MS, ICP-AFS, ICP-AAS, ICP-AES-GC and ICP-AES-HPLC.

Nanoindentation has been increasingly developed as an important testing method for measuring the micro-mechanical properties of material, and emerged as a powerful tool for measuring the mechanical properties of wood cell wall. The nanoindentation technology and its working principle were briefly introduced in this paper, and the domestic and international progress of using nanoindentation for determining the mechanical properties of wood cell wall in recent years and the problems faced were discussed. The potential research direction of nanoindentation in wood research was proposed. The study was aimed at providing references for the basic research in mechanical properties of wood cell wall and the scientific utilization of wood material.

Parts with complex curved features has been widely applied in areas such as aerospace, energy and power. With the development of these high-end equipment fields, there is an increasingly higher demand for the machining efficiency and precision of such parts. In high-feed-speed numerical control machining of parts with complex curved features, the contouring error is non-ignorable due to the existence of tracking errors for each feed axis caused by servo delay of feed-drive systems, which seriously restricts the machining efficiency and precision of such complex parts. Consequently, a contouring-error reduction approach based on real-time tracking-error compensation is proposed in this paper to improve the machining accuracy of such parts without decreasing of the machining efficiency. According to the transfer functions of the feed-drive systems, the tracking-error compensation values for feed axes are calculated by solving differential equations. After compensation, the tracking error of each feed axis can be dramatically decreased, thus the contouring accuracy in high-feed-speed machining can be effectively improved. Simulation results demonstrate the feasibility of the proposed method. This study is significant for improving the machining efficiency and precision of parts with complex curved surface.

For Cr12MoV die steel plane grinding surface integrity, this paper makes a three-dimensional finite element simulation of Cr12MoV die steel grinding surface residual stress by using the thermo elastic plastic finite element method, neglecting the influence of phase change of the materials. The calculated values of different residual stresses are obtained by changing the grinding parameters. The results showed that the surface of Cr12MoV die steel has the highest temperature and the residual compressive stress exist. Vertical grinding direction have greater residual compressive stress than parallel grinding direction, and the grinding surface residual compressive stress increased with increase of grinding depth and workpiece speed, while decreased with increase of the roating speed of the grinding wheel.

The path following technique can improve the repeatability and objectivity of the vehicle performance test. In order to improve the path following algorithm application, a new path following algorithm based on a three degree of freedom vehicle model was proposed, considering nonlinear characteristics of side slip angle and lateral force. The effectiveness of the path following algorithm is verified by matlab simulation.

A vortex type air compressor is a new type of rotary compression machinery. It has the characteristics of high efficiency, stable operation and low noise. The static vortex plate and the moving vortex plate are its two important parts. In this study, Leitz Reference HP three coordinate measuring machine (CMM) was used to analyse them in the reverse engineering of the measurement of the workpieces. The 3-2-1 method was used to build the coordinate system, the contact scanning probe was used to measure the static vortex plate and the moving vortex plate in closed loop mode to obtain the measurement data of internal and external surfaces. Processed data were imported into UG software. The UG’s function of “Free Form Feature” was used to reconstruction surface models. CMM was used to calibrate the established mathematical models. Finally it’s concluded that the results are conform to the requirements of the mathematical models.

Basing on the combination of the five-axis carving, the milling technology and the traditional machining technology, some parts of the design of five-axis carving and milling machine has been done and the three-dimensional model of the machine has been finished accordingly. This paper focuses on the whole structure modeling, the structural design of welded bed, the analysis and optimization. Because the welded bed is made of many steel plate welded, the strength of structure is weaker than the needed. Through the research of the welded plate, the strength of the machine can be strengthened if the bed is melded by different kinds of little steel plates around the bed. And by the analysis of the steel plate welded styles from different schemes, the optimal scheme can be presented to make sure the strength and stiffness.

In view of the traditional Kalman filter algorithm the shortcoming which the probable error fill-out even diverges when the model errors exist, considering the RBF neural network has the strong non-linearity to approach ability, propose assisting the Kalman filter with the RBF neural network the new algorithm, and apply it to transfer alignment of carrier aircraft’s INS. Simulation results indicate this algorithm surpasses traditional the Kalman filter algorithm.

With the shape of the cooling channel being formed by the multi section of curved holes, the cooling water channel can be arbitrarily arranged according to the mold cavity, which can effectively reduce the temperature of the mold and improve the quality of the products. This paper describes the self guiding curved hole machining method based on the principle of electrochemical machining. In the analysis of curved hole machining process of cathode electrolyte flow field, designed the electrode structure and the liquid outlet form, used the RNG k-εmodel, a numerical simulation is performed on the stable machining of an electrolyte channel, then according to the simulation results, optimized the design of the electrode liquid outlet shape.

In order to realize the intelligent control of the classroom, this paper studies the method of detecting the crowd in the classroom. Combining with the characteristics of the population distribution in the classroom, the paper uses the gray Hough transform and the background image to draw the rule of the human head region, select the morphology and divide the watershed algorithm, and finally mark the head target. I am using BP and RBF network head target classification.

Based on the mechanism of side pole impact, the influence of energy transmission and crashworthiness between minivan and sedan’s center of gravity, structure and packaging was compared and analyzed herein. The improvement direction of minivan structure was put forward by the analysis. The simulation of minivan side pole impact and structural optimization was carried out. The results show that crashworthiness performance of minivan is improved significantly, which proving that the optimization methods of minivan side pole impact were viable.

FEM models of semi-armor-piercing warhead penetrating double-layer aircraft carrier target are established, based on which the dynamic response processes of the warhead penetrating the target with two different attack angles of 0° and 10° are calculated. The results show that the posture of the warhead after penetrating the flight deck suffer an obvious change which causes notable increase in attack angle to the car deck. Ductility reaming damage mode and adiabatic plugging damage mode are exhibited in the penetration process. Durative high accelerations come forth in the penetration process leads to serious erosion in nose of the warhead and s an obvious structure distortion of the warhead. The research could provide reference for the warhead design and corresponding study on damage effect.

The access control of Serial compensation monitoring IED is a key chain in online monitoring system of serial compensation station. The article researches on the serial compensation station condition monitoring IED based on IEC61850 access process, the communication pattern between monitoring IED and the monitoring host and the modeling method of monitoring IED IEC61850. It also gives the information model and introduces the technology of real-time monitoring IED and historical data processing, and finally presents the implementation method.

In order to meet different requirements of experimental temperature inside ultrasonic machines, a new outboard device have been developed and able to make the inner liquid environment of an ultrasonic cleaner maintain a constant temperature. This device can not only maintain a constant temperature range of the target liquid environment, but also be convenient for moving, dismounting and installing on machines of different sizes. In order to realize effects of a constant temperature, a temperature control system is used in this device to analyze temperature data and conduct logic design on them so that heating or refrigerating are under control. A semiconductor chilling plate is applied to be the refrigeration core of the refrigeration system, assisting with a cooling system against the heating surface of the semiconductor cooler. According to test results, this device can maintain liquid within 10L in a constant temperature range of 10-60°C, error within 0.5°C.

Aiming at the question that there are more factors affecting kinematic accuracy of planar mechanism and they cannot be ignored, the influence factors of the reliability in kinematic accuracy of planar mechanism are classified as noncumulative factors and cumulative factors. The reliability simulation test for kinematic accuracy of planar mechanism is proposed under the coupling of noncumulative and cumulative factors. According to the reliability simulative test, the allowed maximum wear extent of mechanism is obtained, the wear rate of hinge is analyzed by Archard wear model. The life evaluation model of probability reliability and the life evaluation model of fuzzy reliability are respectively established on the basis of the allowed maximum wear extent and the wear rate. The life evaluation of mechanism is done respectively by the two models above and the assessment results are compared with each other. Finally, the feasibility of the proposed method is demonstrated by taking slider-crank mechanism wildly used in engineering practice as an example to analyze. The kinematic accuracy under the condition of different hinge gaps and reliability life of the mechanism are obtained from the analysis.

This manuscript focuses on a dissemination method with specified platforms which is designed for a weighing robot produced by SIMT. It is suitable for both OIML R111 and Chinese customary usage. Dissemination method with specified platforms is a kind of subdivision. We don’t change the principle of subdivision but make some changes in weighing method. Dissemination method with the specified platforms makes the automatic weighing robot reach no weights drop. With the analysis of the uncertainty and the accuracy, this method is proved to reach the requirements of E₂ class mg weightgroups. Three characteristics of SIMT’s weighing robot with a dissemination method are standard applicability, method variety and no weights drop. Dissemination method with the specified platforms is a bold attempt in mg weightgroups’ calibration. Since the error of the specified platforms can’t be corrected completely, this method is only suitable to mg weightgroups (E₂ class and down). We can’t calibrate the E₁ class mg group weights with this method.

In order to study the relationship of wheel turning angles of different steering axis, the all-wheel steering model of nine-axle all terrain crane was established. The calculation formulas of inside and outside wheel turning angles of different steering axis were deduced. The results showed that the inside wheel turning angle is bigger than the outside one at the same steering axis, the rest inside wheel turning angles increase with the increase of the inside wheel turning angle of the first axis. Small turning mode can be realized when the turning direction of the front five and the back four steering wheels is opposite. The conclusions in this paper can provide reference for the design of multi-axle steering of nine-axle all terrain crane.

The development of the global marine industry led to a surge in demand for offshore platform crane, due to its complex working environment makes the research for offshore platform crane is less, So the strength calculation and modal analysis of the boom of the offshore platform crane are carried out by using ANSYS in this paper. Firstly, the load of the offshore platform crane is analyzed based on the API-2C specification; then the static analysis and modal analysis of the boom are carried out by using ANSYS and obtain the weak points, natural frequency and mode shapes of the components. The analytical results show that the material of boom meet the requirements of strength and stiffness; because the natural frequency of the winch drum and the fluctuating wind load and the boom is partially overlapped, we should pay attention to the speed of the winch drum or the structure reforming of the boom in order to avoid resonance in using.

Snake rolling is a newly developed asymmetrical rolling technique which has both different speed ratio and horizontal offset distance. But the industrial application of the snake rolling is still on its way because it needs completed science researching. The combination of the snake rolling and the 2024 T39 process on the mechanical properties of the final product is investigated in this paper. Multi-pass snake rolling was conducted in our work. Compared with the same plate in conventional rolling, The tensile strength shows almost the same. But the Kahn tear test evidently showed that snake rolling improves the Unit Initiation Energies of the 2024 aluminum alloy plate dramatically by 60.5% in average, and, without loss its strength. Moreover, the snake rolling also reduced the anisotropy of UIE in maximum 63.0%, compared to conventional rolling, owing to the stronger {111}//ND shear texture.

Creep age forming applications of 2xxx series aluminum alloys are much less than 7xxx series, which is due to the difficult control of material property and microstructure at the end of forming. Based on a four-point-bend forming tools, effects of pre-stretching on the springback, mechanical property and microstructure of 2124 aluminum alloy in creep age forming were investigated. The springback appears a ‘V’ type variation feature owing to the competition between the creep-acceleration effect of pre-stretching and the diminishing sheet thickness. And the strength property curves of the 2124 aluminum alloy present a bimodal variation characteristic with increasing pre-stretching. The first peak is related to the finer and denser intragranular precipitates caused by the introduce of pre-deformation, and the second peak is attributed to the obvious elongated grains along the tensile direction by the excessive deformation. The results of the verification test indicated that choosing a proper pre-deformation can achieve coupling control of the forming target and the material property in creep age forming process, and the recommendatory pre-stretching range for the creep age forming of 2124 aluminum alloy is 1.5%∼2.5%.

The hardness test and transmission electron microscopy (TEM) have been conducted to study the effects of stress aging on properties and microstructures in Al-2Cu alloy bicrystal The Al-2Cu specimens were aged to peak strength under various compressive stresses. The results showed that stress-orienting effect occurs in single crystal, but this effect is inhibited neighbor to grain boundary of bicrystal. And that precipitates θ near the grain boundary were fine and dispersed. Compared with stress free aging, the difference of hardness, between single crystal and grain boundary after stress aging treated, is lower, as result of the precipitates free zone (PFZ) narrowed. The results of this research provide important insight into solving the anisotropy problem attributed to precipitation strengthening in the manufacture of Al-Cu alloys.

This paper reviews contact modeling with an emphasis on the statistical methods contact model. These models include simple Hertz contacts for spheres. Further generalizations include the fractal theory model. Contact with a rough surface is generally represented by a multi asperity contact model. Included is the well-known Greenwood–Williamson contact model, as well as a myriad of other models, many of which represent various modifications of the basic theory. Also presented in this review is a description of wavy surface contact models. These models inherently account for the coupling between each of the contacting areas. A brief review of experimental investigations is also included. Finally some recent work, which addresses the dynamics and associated instabilities of sliding contact, is presented and the implications discussed.

In view of the increasingly serious shortage of supply and demand of fly ash in various regions and the urgent need to develop a comprehensive utilization of granite stone, the application of different fineness of granite based composite mineral powder in aerated concrete is put forward. This paper aims to study the influence of different fineness of granite powder on the properties of aerated concrete under different autoclave time and autoclave pressure, to find out the more suitable autoclave pressure, autoclave time and the fineness of granite. Improve the comprehensive utilization of granite waste, thereby reducing the pollution of the environment, improve economic efficiency.

Granite clast is industry garbage. For solving the problem about wasting of resources and environment pollution, the reuse of industry waste as a partial replacement of cement becomes a valuable discussion. The main objective of this study is to find the best mixing ratio of granite powder and slag powder replacing fly ash as the replacement of cement. The main work of this experimental program included the preparation and physical property test of the granite-based composite powder, the test of the working performance and mechanical property on granite-based composite powder (GBP) mortar. The experimental parameter was the mixing ratio of granite powder and slag powder. The GBP optimal components ratio is 60% of granite, 40% of slag and addition 1% of gypsum.

Purposes To study the preparation of novel micro-structural composite solid lubricating layer, Methods Ion implantation technology together with low-temperature ion sulfurizing technique were used to prepare the MoS₂/FeS composite film. The as-prepared film was characterized by scanning electron microscope, X-ray photoelectron spectroscopy and nano indenter. The elastic modulus and hardness of the substrate and MoS2/FeS film were measured by nanoindentation. Results the composite film has a microspheric structure with uniform particle diameter approximating 500 nm. The composite film mainly consists of MoS₂, FeS and a small amount of oxides. The hardness of the substrate and the composite film were 6.57Gpa and 7.89Gpa and the elastic modulus were 223.8Gpa and 246.2Gpa. Conclusions The hardness and elastic modulus of the composite film increases by 20% and 10%, respectively, referenced to those of the substrate. The elastic characteristic value H/E also increases by about 10%. As a result, the corresponding wear resistance of the composite film is better than the substrate.

In recent years, university-industry collaboration (UIC) is known as a new mode of the research and development (R&D) of the composite technology, which is widely focused by the composite industry. In present research, the overall development, regional distribution and cooperation relationship of the UIC in the advanced composites material industry is analyzed according to the advanced composites material patents (ACMPs) applied by universities and enterprises from 2009 to 2014 in China. Results obtained in the study show that the overall development of UIC in the advanced composites material industry is at the stage of tracking and catching-up. At present, the UIC system is far from perfect and the mechanism of scientific achievement transformation has not been still established in the advanced composites material industry. Geographical distance has not significant impact on the ACMPs applied by universities and enterprises. There are considerably differences about ACMPs among the eastern, central and western regions, which has positive correlation with the level of economic development. The cooperation relationship of UIC in the advanced composites material industry is comparatively loose and the characteristic of network is not obvious. The UIC model is not widely recognized.

The traditional method of reliability assessment is established on the basis of large sample theory that requires a lot of field test samples and long test time. This is unable to endure many industry enterprises. Especially for CNC machine tools of this kind of high reliability, small sample size expensive equipment, Because of the large cost of test, the data we can get very few, Limited data may result in low confidence level of reliability assessment or not accurate estimate. So the traditional estimation method is special not and very high reliability of products. In this paper, taking a CNC machine as the research object, according to the reliability of the relevant mathematical theory, Application of weibull distribution test failure time distribution model parameters, And further calculate the reliability index, such as reliability, and effectiveness, MTBF, etc. Through experiments, it shows that proposed method is suitable for numerical control machine reliability assessment requirements.

A 700MPa grade high strength roll-forming steel had been developed and used in bus lightweight. Some application cracking problems and its corresponding measures had been studied. The results showed that the present of higher inclusions (MnS, TiN, etc.) in raw materials and larger internal stresses in arc of the tubes were the main reason leading to cracking. By reducing the contents of P, S, and N elements, improving the rolling, cooling and coiling processes of the raw material and the roll-forming processes of the tubes, those problems had been fully solved.

Mold temperature plays an important role in injection molding technology. The heating process for electric hating and steam heating methods are numerically compared. The results suggest that the steam heating technique provides much higher short-term heating efficiency, while the electric heating method supplies higher long-term temperature. The steam heating method presents higher effectiveness than the electric heating method.

A new type of organophilic clay gallant was discovered in which the organic cations derived from organic salt compounds provide improved gelling properties in organic solvents. It was discovered that that the tail length of the surfactants can affect the suspension property of organically modified sepiolite significantly. Furthermore, it has been discovered that surfactant CTAB has stronger suspension properties than the other three surfactants, accompanying with an 80% suspension value. The present research provides an improved, more efficient organophilic clay gellant for gelling or thickening non-aqueous solvent-based compositions. Besides, the results of SEM demonstrate that the introduction of CTAB is favorable to the dispersion of sepiolite fibers, leading to a better suspension value of sepiolite suspensions. Besides, FTIR spectra analysis indicate that the formation of hydrogen-bonding during the adsorption of surfactant molecules onto the sepiolite particles.

Based on the analytical solution of Reynolds equation for the plane slider of finite width, the effects of the length ratio, ratio of length to width and rotation angle on the average pressure are analyzed and optimized. The results show that there exists optimal ratio of length to width to maximize the average pressure while the area or width of the plane slider is constant. While the ratio of length to width is greater than 2, there exists optimal length ratio to maximize the average pressure. The hydrodynamic pressure obtains the maximum while the directions of the height gradient and movement of surface texture are the same.

The polystyrene particles are generally applied in POCT as fluorescent indicator. In this paper, we have prepared polystyrene particles with the diameter ranging from 50 nm to 400 nm by miniemulsion polymerization, which can satisfy the demand of POCT.

AZ91 magnesium on SiC poroues preform and interfacial reaction between SiC and AZ91 magnesium were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), friction and wear testers and micro-hardness testers. The results indicate that magnesium has a good wettability on SiC and can spontaneously infiltrate the porous SiC/starch preform after a 5h infiltration at 750□. Moreover, interface reaction at the front of magnesium melt was found between the SiC and AZ91 magnesium, which improves wettability between each other. The massive oxidized SiC powders have uniform distribution in AZ91 magnesium metal matrix. The micro-hardness of SiC/Mg composites is 383HV_0.2 and more than 5 times higher than that of AZ91 magnesium (72HV_0.2). Under the conditions of dry sliding wear and 4N loads, compared with the unreinforced AZ91 magnesium matrix, the friction curve of the SiC/Mg composite fabricated by pressureless infiltration is much lower than that of AZ91 magnesium, which means SiC/Mg composites have a better wear resistance.

NiZnO thin films were grown on c-plane sapphire substrates by photo-catalysis metal organic chemical vapor deposition system. The samples with the different catalysis intensity were grown and the effects of catalysis intensity on the crystal, optical properties and surface morphology of the NiZnO films were researched. With the raising catalysis intensity, it can be found that the grain size of samples increased and thecrystal and optical properties improved remarkably. The main reason was the photon energy can provided the chemical processing higher activation energies and diffusion ability, whichwas benefit for atomic rearrangement to decrease the defect density. The photocatalysis had an important effect in the films oxidation process by MOCVD.

Micro-accumulation forming is an appropriate technology to fabricate the parts in micro scale. The paper selects two different aluminum plates as the bipolar plate blanks to perform the accumulated forming experiment, which are 11mm×11mm×0.165mm and 11mm×11mm×0.27mm. Then, it is obtained that the forming performance and the influence of different amount of forming reductions on the forming depth and springback rate. The experiment shows that the new forming method is appropriate for the flow channel of bipolar plates.

In order to improve the flame retardancy of fiber modified phenolic foam composite materials while reducing its friability, phenolic foams incorporated with 3mm rock wool fiber were prepared. The morphology, mechanical and thermal properties of the foams were investigated. Results showed that the friability of 5wt% rock wool fiber reinforced phenolic foam decreased by 40%, and the compressive strength was increased by 118%, compared to the plain phenolic foam. In addition, the LOI value of the phenolic foams containing 5wt% rock wool fiber increased by 21% than that of unreinforced material.

A Hamiltonian model is developed for analyzing viscoelastic problems with annular-sector domain by using of the polar coordinate system and elastic-viscoelastic correspondence principle. Making use of the state space method, a complete eigensolution space, including zero eigenfunctions and non zero eigenfunctions, is successfully established. Due to the completeness of the solution space, the final solution of any viscoelastic problem can be expressed in terms of linear combination of the eigenfunctions. The corresponding unknown coefficients are determined by using prescribed conditions on the circular boundary. Further, using the variable substitution method, the lateral boundary conditions are transformed into a particular solution which can be obtained by applying the eigenfunction expansion.

By applying the Laplace integral transformation, the time domain viscoelastic governing equations are transformed into those of Laplace domain, and therefore the Hamiltonian system is applied successfully. Moreover, the dual equations are established using the displacement and stress components as fundamental variables, and accordingly the viscoelastic problems are reduced to finding zero and non-zero eigenvalue eigensolutions. Zero eigensolutons do not decay with the coordinate, and they can describe traditional Saint-Venant problems. Non-zero eigenvectors are local solutions. These general solutions construct a complete eigensolution space.

Ordered mesoporous PFR-Fe/C composites have been synthesized for the first time via a “one-pot” assembly strategy associated with a direct carbonization process by using phenolic resol (PR) as a carbon source, inorganic salt hydrated iron nitrite as an iron source and amphiphilic triblock copolymer Pluronic F127 as a template. The main strategy of this approach is to use the iron precursors as the coordinationcenter with phenol. The obtained mesoporous Fe/Fe₂O₃/carbon composites (PFR/C-Fe) exhibit uniform pore sizes about 6.78 nm, high specific surface areas about 572 m² g^-1, and high pore volumes 0.70 cm³ g^-1.

Hydroxyapatite porous microspheres were fabricated by multiple emulsion. XRD and FTIR reveal that the as-obtained samples consisted of hydroxyapatite. TEM and SEM showed that the as-prepared products were composed of porous microspheres assembled with nanorods and had three-dimensional nanoporous nanostructured networks. These nanoparticles aggregate to form porous with a pore size of 2.5-9.5nm among them. The formation mechanism of porous microspheres has been discussed.

The molybdate conversion coating for 6063 aluminum alloy was prepared with Na₂MoO₄·and K₂ZrF₆ via the dip process. The physical and chemical properties of conversion coating were analyzed by CuSO₄ dropping corrosion test, electrochemical impedance spectroscopy (EIS), scanning electron microscope (SEM) and energy-dispersive spectrometer (EDS). The optimized process conditions are as follows: Na₂MoO₄·2H₂O 6 g/L, K₂ZrF₆ 3 g/L, pH 3, temperature 40 °C, and reaction time 10 min. The conversion coating exhibits yellow color and consists of Mo, Zr, Mg, Al, O.

Fe₃O₄-graphene oxide composite nanocrystals with diameter of about 20 nm were prepared at 200°C for 12 h in a closed vessel containing an appropriate amount of ferrocene powder, grapheme oxide and distilled water. Magnetic measurements show 38.18 emu/g of saturation magnetization (Ms) of a typical sample, which is lower than 66.77 emu/g of the corresponding metal Fe₃O₄ bulk material. This is attributed to the considerable mass of the graphene oxide and nature of the magnetic nanocrystals.

A mine of Tangshan which has steep terrain of the waste dump and accumulation of waste slag and rock provides the solid loose material conditions for the occurrence of the dump landslide debris flow. When the rainy season comes, the water resources brought by the rainfall provide sufficient conditions for the occurrence of debris flow, and surface runoff provides dynamic conditions for the movement of debris flow. Therefore, during the period of rainfall, the mine waste dump slope seepage is serious, and landslide type debris flow will most likely happen in the waste dump slope. By utilizing numerical simulation software Geo-studio, this paper makes a deep analysis on the influencing factors of rainfall intensity and rainfall duration, and obtains the stability of the waste dump slope and the relationship between stability and the rainfall intensity and rainfall duration. The discussion of the safety problem of the waste dump slope can provide the theoretical basis for waste dump to take effective measures to prevent the debris flow.

Taking waste dump slopes of Tangshan Sanyou Mine for example, this paper simulated the waste dump slopes that under the influence of different accelerated speed peak values with earthquake action by utilizing numerical simulation software Geostudio and analyzed waste dump slopes’ stability changes under the influence of earthquake action. According to the result of numerical simulation, with the increases of peak value of earthquake wave accelerated speed, the safety stability coefficient decreases gradually and slopes of waste dump gradually develop from a basic stable state to the unstable state. When peak value of earthquake wave acceleration is smaller than yield acceleration that resulting in the destroy of slopes, the weakening of the earthquake action on the slope stability degree is small. On the contrary, once the peak value of the earthquake wave acceleration is greater than the yield acceleration of the slope, it has a serious impact on the stability of the slope.

Poly (Acrylamide/ Acrylic acid/ 2-Acrylamido-2-methylpropane sulfonic acid) microspheres were prepared by inverse phase suspension polymerization whose reactive systems were initiated with potassium persulfate (KPS), cross-linking agent of methylene-bis-acrylamide (MBA), and suspending agent of Span-80. The structure of terpolymer microspheres was characterized by fourier transform infrared spectroscopy (FTIR). Their sphericity, particle size and expansion behavior were investigated with scanning electron microscopic (SEM), and a laser particle analyzer. The plugging effect of these microspheres was evaluated with nuclear-pore membrane filtration. The results showed that the average particle size of the cross-linked terpolymer microspheres was 16 µm with narrow size distribution, and these microspheres showed high swelling ratio and stable salt resistance. In addition, the terpolymer microspheres dispersed systems exhibited effective plugging on a nuclear pore membrane with 2 µm pores due to their deformation property. These functional microspheres may provide a candidate material for plugging the leaking cracks and high permeable channels in petroleum engineering.

For the structural design of a filament winding composite engine case, one of the case design methods named netting theory was used to get ply thickness of spiral winding and hoop winding for cylindrical figure, and ply thickness of case head designed by equal stress conditions, under the two design pressure 20MPa and 25MPa. Combining with process parameters and stress design formula, the numbers of the case hoop winding and spiral winding cycles were obtained, and 8 spy programs were acquired. The finite element analysis results showed that loop winding between hoop winding and spiral winding could reduce shear stress between layers, and symmetrical ply sequence contributed to increasing the rigidity. By comparing the results, 25MPa is the best design pressure for a composite spies, which meets the axial and circumferential direction internal forces requirements, meanwhile it increases effective utilization of fiber strength.

To evaluate the effect of silica coating with Sol-Gel processing on the bonding strength between dental high-strength ceramic and composite resin. Method: 80 zirconia ceramic discs were randomly divided into four groups (n=20 in each group), and received different surface treatments, then the shear bonding strength of the ceramics and composite resin were calculated. Results: The three groups with silica coating had a higher bonding strength than the un-coated group with a significant difference (P<0.05); group C had the highest bonding strength (P<0.05). There were no significant differences between group B and group D (P>0.05). Conclusion: Silica coating followed by silane coupling agent treatment can significantly increase bonding strength between dental ceramic and composite resin; 30% silica sol may be more effective.

Pressure test is a necessary part of quality examination for the steel tube production. In order to guarantee the safe reliability of production process, it is significant to study the feasible fault diagnosis methods for the pressure testing process. According to the nonlinear character and multiple phase of the hydraulic pressure testing process, a phase-based recursive kernel Fisher discriminant analysis(RKFDA) method is proposed in this paper. Combining with recursive conception and kernel technology, the method builds diagnosis models using the fault information extracted from the previous phase and sample data in the current phase. The simulation results show that with the proposed method, the fault diagnosis of batch processes with nonlinear characteristic has been realized effectively.

According to the study of rubber fatigue, it is hard to precisely ascertain constitutive equation and its corresponding parameters which can cause distortion of analysis results, and the relationship of strain-stress of commonly-used hyperelasticity constitutive models is discussed in the finite element analysis under different deformation states, then the fitting and prediction ability of different constitutive models on mechanical properties of rubber materials is analyzed when the kind of deformation changes under a series of experiment designs. It indicates that there are obvious differences of varying constitutive models on the fitting and prediction ability of deformation. Under large deformation circumstance, Ogden model has good fitting capacity when the data are enough; under small deformation circumstance, Neo-Hooke model has an advantage in computation. For two random groups of deformation data, Ogden model is more applicable in numerical fitting based on uniaxial tension (UT) and equal biaxial tensile (ET) data, while Yeoh model is more applicable in numerical fitting based on uniaxial tension (UT) and planar tensile (PT) data.

In this paper, a molecular level hybrid material consists of glycidyl-polyhedral oligomeric silsesquioxanes (G-POSS) and bisphenol-A epoxy resin (EP) with chemical bonds connection was prepared. The curing reaction and surface characteristics of the hybrid materials were investigated by differential scanning calorimetry (DSC) and scanning electron microscope (SEM), respectively. With the increase in the loading of G-POSS, the Activation Energy (Ea) shows significant decrease and the mechanical properties of the EP were greatly improved. The EDS results revealed a uniform dispersion of the G-POSS in the hybrid materials. The G-POSS/EP composites exhibited excellent dielectric properties and thermal properties due to the voids volume in the composites. The results manifested that the introduction of G-POSS to EP exhibited excellent toughening and reinforcing effects on the composites.

The nitride semiconducting materials are stable in the hexagonal wurtzite structure; they exhibit the largest extension of direct band gaps for one alloy family (AlN: 6.2 eV, GaN: 3.5, InN: 0.65), thus are able to cover from the UV to IR wavelength for emission and detection applications. They are obtained as thin layers mainly grown on foreign substrates. As these materials are expected to exhibit high thermal and mechanical stability in addition to the interesting electronic properties, they are due to find applications as high power high frequency components. However, the active parts are made of alloyed heterostructures, and the three compounds exhibit highly distinct physical properties. Therefore the assistance of structural investigations to the fabrication of the devices has been proven to be indispensable. In this work, we report part of our extensive investigations of the growth defects using transmission electron microscopy and theoretical modelling.

Poly (vinylidene fluoride) (PVDF)/poly (acrylic acid) (PAA)/calcium carbonate (CaCO₃) composite membrane were prepared by in-situ mineralization method. PAA is used as polyanionic macromolecule to induce the generation of CaCO₃ particles. The mineralization condition was optimized based on CaCl₂ content in the casting solution and carbonate source selection. Structures were characterized in detail by FESEM and XRD for the prepared composite membranes. Results confirm that CaCO₃ particles consisting of calcite and vaterite disperse uniformly on the membrane surface and in the membrane cross-section. The improved hydrophilicity is resulted from the membrane structure in the in-situ mineralization process and the collapse of PAA chains in the membrane pores. Therefore, pure water fluxes of the membranes were improved about ten times. Our work indicates that the in-situ mineralization method is convenient and beneficial to prepare hydrophilic composite PVDF membranes.

Polypropylene/poly (butylene terephthalate) (PP/PBT) blends containing organo-montmorillonite (OMMT) were prepared using a twin-screw extruder. Aim of this work was to study the morphology and properties of PP/PBT/OMMT composites. The weight ratio of PP to PBT was kept at 70:30, while the weight fraction of the OMMT was varied from 0 to 7 wt%. The OMMT dispersion was evaluated by transmission electron microscopy (TEM) and the phase morphology of composites was evaluated by scanning electronic microscopy (SEM). The results showed that the OMMT layers were mainly intercalated and well dispersed in the PP/PBT matrix. The thermal properties, mechanical properties and rheological behavior of PP/PBT/OMMT composites were also evaluated.

The backfill was assumed infinite when calculating the earth pressure using Coulomb’s or Rankine’s theory. Actually most of the retaining walls we meet often have the narrow space of backfill. Due to the active wedge development limited by narrow backfilling space behind retaining wall, the active earth pressure (hereinafter referred to as AEP) is less than the theoretical calculation results. In this paper, the author studied the AEP on rigid retaining walls (hereinafter referred to as RRW) using experimental study. In the experiments, the narrow backfill space was mainly restricted by different backfill width and inclination of the rock face. The AEP on RRW with narrow backfill space is usually far less than the theoretical calculation results. And the ratio of the value of the AEP in the study over the value of theoretical solution is about 0.5-0.7. In addition, this paper also studied the effect of the aspect ratio of the backfill on AEP.

As a membrane process between ultraflitration (UF) and reverse osmosis (RO) nanofiltration is widely used in wastewater treatment, dye separation and desalination for its energy-efficient process. Layer-by-Layer (LbL) self-assembly technique is one of effective approaches to nanofiltration layer on support membrane via alternate deposition of building blocks by various non-covalent interactions. In order to extend the applications and improve the performance of LbLnanofiltration membrane, we induce organic-inorganic hybrid nanoparticles as the building block to fabricate nanofiltration composite membranes and focus on the effect of hybrid nanoparticles on self-assemble behavior, membrane structure and separation performance. Atom transfer radical polymerization (ATRP) initiator is anchored onto the surface of silica nanoparticles and initiate polymerization of N, N-dimethylaminoethyl methacrylate (DMAEMA). The PAN-based composite membranes are fabricated by LbL assembling of quaternized PDMAEMA@ SiO₂ (PMETAI@SiO₂) nanoparticles and PAA on hydrolyzed PAN ultrafiltration support membranes. The results indicate that the water flux has a maximum value with pH varying from 2.0 to 6.5. On the other hand, it shows opposite tendency with the increase of ion strength. The membrane exhibits high rejection of Congo red, which is contributed to small pore size and Donan effect.

Microwave technique is a powerful tool for non-destructive testing. In this paper, microwave testing was utilized to examine thermal fusion welds of high-density polyethylene (HDPE) pipeline containing void defects. Thermal fusion welds containing void defects were examined by using a vector network analyzer. The reflection coefficient S₁₁ of the weld samples containing void defects was measured at four symmetrical positions. At the most sensitive wavelength frequency, the S₁₁ showed different values at varied positions, based on which the existence of voids can be detected. The readily detectable differences in S₁₁ make detection of the voids possible. True density experiment and tensile mechanical tests were carried out to confirm the reliability of the microwave testing methods. This work provides great insights into inspection of defects in thermal fusion welds of HDPE pipelines.

Chirp sub-bottom profile data not only can be used for the interpretation of seabed geological information, but also can be used for seabed sediments classification. At present, there are mainly two kinds of seabed sediment classification methods base on SBP (sub-bottom profile) sonar data: (1) the echo signal statistical characteristics classification; (2) acoustic parameter inversion method. The first classification methods are similar, which is based on statistics, unknown sediment type can be concluded according to the statistical characteristics of known sediment. Seabed acoustic characteristic parameters are inversed and thus seabed sediment can be classified. Under the condition of limited data, the comprehensive utilization of the two methods provides a more accurate remote sensing method for seabed sediment classification

Clay brick with continuous development of limitations, this paper mainly studies under the different design strength grade of lightweight ceramsite concrete hollow brick density and compressive performance of experimental result analysis, analyzes the development of various new building materials in China can adjust measures to local conditions to use a lot of industrial waste residue, waste and agricultural residues, etc., through processing and manufacturing ceramsite concrete hollow brick used in wall, for profit, thus victims of freshwater.

Cold plasma under vacuum conditions was used to surface modification of PET fibers and fabrics usually. In order to be cost-effective, a renewed interest is concentrated in generating atmospheric-pressure non-equilibrium plasmas. Atmospheric pressure dielectric barrier discharge, running in the environment (Ar, N₂-Ar, O₂-Ar), was used to continuously treat poly(ethylene terephthalate) fabrics. It was found that the wettability, antistatic ability and dyeability were significantly improved according to the data derived from the measurements of the water contact angle θ, electrostatic half-decay time, K/S value, color differences ΔE*, and scanning electron microscopy. These results are extremely valuable for further application to surface modification of polymer materials.

A novel gas sensor based on cataluminescence (CTL) on the surface of nanosized Ti₂W₃O₁₃ was demonstrated for direct determination of ammonia in air. Trace ammonia was firstly absorbed on active carbon at room temperature to concentrate, then desorbed at 105°C to determine. The sensor showed high selectivity to ammonia at wavelength of 540 nm, satisfying activity at temperature of 180°C and good stability at air carrier flow rate of 120 ml/min. The linear range of CTL intensity versus concentration of ammonia was 0.8∼70 mg/m³ (γ=0.9991), and the detection limit (3σ) was 0.5 mg/m³. The recovery of artificial sample was 97.4%—102.5% by this method. There was no response to benzene, SO₂, CO, ethanol and formaldehyde. This sensor allows on-line monitoring of ammonia in air.

A cataluminescence (CTL) based method for simultaneously identifying and determining formaldehyde (HCHO) and sulfur dioxide (SO₂) in air was proposed. The experimental conditions meeting the algebraic sum rule of the CTL intensities of HCHO and SO2 were sought. They are two analysis wavelengths of 460 nm and 580 nm, the surface temperature of sensing materials of 280°C and the flow rate of air of 130 mL/min. The limits of detection of this method were 0.08 mg/m³ for HCHO and 0.6 mg/m³ for SO₂. Common coexistence matters, such as acetaldehyde, ammonia, benzene, ethanol, hydrogen sulfide and carbon dioxide, did not disturb the determination.

Aluminum phosphate is matrix material; it was added 20wt%, 30wt%, 40wt%, 50wt%, 70wt% of aluminum borate whiskers, and was sintered at 700 °C to 1400 °C. Through studying the material samples of aluminum borate whisker reinforced aluminum phosphate, compared the Vickers hardness and fracture toughness of different proportions samples at different sintering temperatures, analyzed the causes that aluminum borate whisker improved mechanical properties of aluminum phosphate, and determined the optimum content of the aluminum borate whiskers and the optimum sintering temperature.

It was difficult to display the radar receiver noise realistically in radar simulated trainer. Analyzed the engender principle and characteristic of radar receiver noise. According to the method of changing uniformly distributed pseudorandom numbers to normally distributed pseudorandom numbers, put forward the calculation step of engender normally distributed pseudorandom numbers. And build the simulated model of radar receiver noise based on normally distributed pseudorandom numbers. Actualized the display function of radar simulated trainer and the display was right. The result of simulation indicated that the simulated model was feasibility, and increased the display fidelity of radar simulated trainer effectively.

The criterion compliance evaluation method of CAD model for electromechanical cable product has been researched. The purpose of this paper is to ensure the design quality and reduce the time and cost of the design changes before the manufacturing stage. The six elements notation of rule definition, the architecture of rule system and hierarchy of evaluation objects have been put forward to build a comprehensive evaluation method. This method is able to measure and estimate CAD model data using subjective or objective evaluation means, and the evaluation priority level and weight coefficient can be determined by AHP. An application system has been developed to achieve the above evaluation process, using knowledge modeling language to define checking rules in CAD model. The problem of complex model evaluation can be resolved by the flexible strategy of man-machine combination. This method and its application have the advantages of high efficiency, simple operation and reliable evaluation results, which has agreeable engineering practicability.

Network information resources and scientific and technological advances, through traditional means access to knowledge has been unable to meet the information needs of researchers under the new situation. Based on the comparison of scientific knowledge acquisition based on the traditional ways and the Internet, introduce development trend of network information resources in scientific research and made comprehensive use of wikis, blogs, RSS, web2.0 technology, networks open resource building Internet environment in the scientific knowledge of information sources Analysis of network research and knowledge sharing technology, introduce new technologies and scientific knowledge-sharing application, present a web2.0 Research new models of knowledge sharing to improve researcher knowledge search scientific research abilities and levels of knowledge sharing.

Taking the rear drum brake used in heavy-duty truck as the research object, a temperature field simulation model was established by using ANSYS and proved to be reasonable by experiment. 260°C was selected as the safety warning temperature of brake drum, 300°C was taken as the failure temperature, and the limited slope length of the average longitudinal slope was calculated. Taking Badaling expressway as an example, the position of Emergency lane was discussed. The results showed that the ultimate slope length of 4% grade by using exhaust united brake of VIII; increased by 72.7% than only using main brake. Under full of loads, the thermal failure of brake does not occur when vehicle using auxiliary braking travels downhill.

In this paper, the thermal stress of different structures was obtained by simulating the load condition of different space spiral structures. The stress that computed in this paper is a reference value, which could not the true stress value. But the stress curve as the reference was used to analyzing the tube structure sensitivity. And the stress was not changed along with the change of the parameter within limits.

Based on the formal definition of Hierarchical Time Colored Petri Nets, and combined with engineering experience, modeling steps in maintenance process modeling is summarized. On the platform of CPN-Tools, the maintenance process model based on HTCPN is established for the equipment maintenance resource configuration. The quantitative conclusion of equipment maintenance effect and resource utilization under different resource configuration conditions is given through the simulation analysis. It can provide reference for the design of equipment maintenance program, and it provides a basis for maintenance resource configuration.

The equation of pressure and stress wave coupling propagation in pipeline was derived and it reveals that the wave energy interact each other due to water hammer, generating serious destruction continuously. The nonlinear mechanism of energy transfer between different modes of the fluid was explained, and the analysis shows that the propagation process of forward and backward pressure wave is not a linear superposition, but a nonlinear one. Thus the transmitted energy increases dramatically, which leads to the amplified nonlinear damage effects. The water hammer can be monitored by the modal shape and the measured signal. The influence of different parameters on water hammer has been studied. Results show that pipe length, diameter and velocity have significant effects on water hammer. When a lower stiffness pipe (LSP) and a multi-band LSP are used to connect the pipeline, the water hammer is not eliminated. However, increasing pipe diameter, reducing the flow rate and the length are beneficial to control the damage of hammer.

Model deformation and attitude angle are very important parameters in wind tunnel test. The deformation data can be used for CFD correction, and the accuracy of attitude angle affects quality and characteristic of test data. In order to get the test parameters. A kind of optical measurement device based on three linear array CCD-Optotrak system, and the measurement technology by the system is introduced. Deformation data at different wind speeds is collected. By installing markers on airframe model and the attitude angle is measured by vector calculation. The test result shows that the system has good application effect. The data curve displays the change of deformation under different wind speeds, and the measurement accuracy of attitude angle achieves 0.004°.

Unstable coil diameter is a common problem in the process of wire drawing, which will lower the quality of steel wires. Hence, all wire manufacturers have a specific requirement on the coil diameter. The problem is mainly attributed to that the wire drawing die’s center line fails to be tangent to the drum, causing uneven stress on the steel wire. To keep the coil diameter stable, the wire drawing die should be adjusted to make its center line tangent to the drum (i.e., “Tiaoquan”, which means coil adjustment literally). In actual production, however, the “coil adjustment” of high-precision wire drawing dies is sometimes more difficult compared with those with low precision or even some defects. Therefore, we made force and springback analyses on wire drawing dies with varying hole structures (standard hole, deflected calibrating strap, and deflected working cone) in the drawing process, with the purpose of determining the relationship between the quality of wire drawing dies and the coil diameter.

In the present work, a new designed bugling test machine is introduced to evaluate the tubular material properties. Differing from previous studies, the new test method allows the tube to shrink along the axis without the end effect. The proposed method is viable to obtain the strength coefficient, work hardening exponent and initial strain in Krupkowsky-Swift work hardening model. To determinate a more accurate result, three common geometrical models (cosine, elliptical, circumferential) are applied to analyze the process of bugling and compared. Bugling test, uniaxial tensile test and a serial finite element simulation on rolled tubes are conducted to validate the results. It turns out that the properties from the bugling test are quite different from the tensile test ones, and implies that the cosine model is the best fit to the experiment. Therefore, it is concluded the parameters from bugling test can improve the accuracies of the numerical simulations of the tube hydroforming.

For reliable nuclear power reactor control, it is of paramount importance to understand the time-dependent character of the neutron population, in order to ensure safe operation. This is especially true under either an expected or unexpected transient in the reactor reactivity. In this paper, a new analytical method based on the Sylvester’s theorem is presented to solve the Point Kinetic Equations (PKE) with average one group of delayed neutrons. The solution is then compared with numerical solutions using the Runge-Kutta method and Euler’s method. Furthermore, a negative reactivity was inserted to validate the analytical solution. The result shows that the analytical solution match is well with the numerical solutions.

Battery equalization is an important part which has to be considered into battery management system. As the existence of consistency problem, available capacity and service life of battery pack are much less than signal fuel cell. Therefore, the balance management of the battery pack has important practical significance of using a group of cells. In order to improve the efficiency of equalization equipment of batteries, a novel control strategy for battery equalization is proposed. The control strategy is designed based on the method of on-line SOC estimation. The SOC is estimated by unscented kalman filter, the estimation result of which is more accurate and reliable. And one capacitor is used as energy transfer media, this system has the advantages of easy implement, low loss in transfer process and fast balancing. The simulation results show that the design can equalize battery packs effectively and the system proposed possesses practical value.

This paper inspects wetting rules of normal acid, alkanol and alkane on surfaces of stainless steel, platinum sheet and monocrystalline silicon and contrasts the influence on wetting effect by polarity difference. Experimental results show that for alkane not containing functional groups, the increasing of carbon number is beneficial to the enhancement of wetting effect; optimum wetting reagents for different surface present obvious selectivity, and for alkane, the wetting effect of stainless steel, platinum sheet and monocrystalline silicon is from good to bag in sequence. For organic alcohol and organic acid, the sequence is monocrystalline silicon, platinum sheet and stainless steel. Organic alcohol and organic acid are monocrystalline silicon, platinum sheet and stainless steel. Liquid solid interface polarity contrast shows that certain wetting difference is beneficial to the enhancement of wetting effect.

In this paper, a method of mixing experiment is adopted to inspect the compounding effect of various additives when oleic acid is taken as base fluid. Experiment result show that although oleic acid has good application effect and can greatly reduce the grinding wheel passivation rate, however, oleic acid, as base fluid, can react with additives due to the existence of functional groups, thereby weakening the application effect of additives. Different reagents in oleic acid base grinding fluid are relatively low in beneficial effects and not large in passivation rate lowering amplitude. Meanwhile reagents are high in interaction property in compounding effect, and can achieve the result of greatly improving grinding wheel passivation, so that oleic acid is not suitable for being taken as the base fluid of additives. In the reagents, adding organic silicon in oleic acid base ceramic special grinding fluid can achieve the optimum grinding wheel passivation reducing effect.

In this paper, mixing experiment method is taken as a main measure, and the interaction of chlorinated paraffin, organic silicon, glycerol and olein in paraffin base fluid is inspected. Experiment results show that singly adding organic silicon can greatly reduce grinding wheel passivation rate and improve machining efficiency, and is an ideal additive during grinding of silicon nitride ceramics. Singly adding glycerol and olein can improve the grinding wheel passivation rate, and is not beneficial to the enhancement of grinding wheel durability. Although the effect is poor when glycerol is singly used, the glycerol can achieve proper synergistic effect, and can further reduce the grinding wheel passivation rate when being used with other reagents at the same time in experiments.

Nuclear power project pricing mechanism has a direct relationship with operation management of construction and also will bring great influence for the investment benefit and industrial development. Through comprehensive comparative analysis of positive and negative electricity price calculation model, this paper presents the study of the main differences and the related influence under different pricing mechanism and the management mode of optimizing nuclear power pricing mechanism, which provides a certain reference for comprehensively and scientifically enhancing the development level and operation stability of nuclear power industry in China.

In the fatigue assessment of welded tubular joints, the hot spot stress around the weld toe plays a significant role. The location of the peak stress around the weld toe determines the initiation position of fatigue crack. Finite element simulation, rather than experimental test, is generally used to carry out analysis for investigation on such hot spot stress distribution because it saves much time and fee. However, the accuracy of the hot spot stress distribution in a tubular joint depends much on its geometry and weld size. This study presents finite element method to analyze the hot spot stress distribution of tubular T-joints. Actual weld size measured from tested specimens and simplified weld size in accordance with AWS specification are both considered in the finite element analyses. It is found from the investigations that the weld size may produce critical influence on the hot spot stress around the weld toe of a tubular T-joint, and the actual weld size is necessary to be considered in the finite element model.

Within the body of defective steel structure strengthened with CFRP, besides CFRP is the main factor influencing the reinforcement, the relative position of CFRP with defects and defect depth also have important effect on the reinforcement. This paper took the static tensile test on 5 groups of non-reinforced, 5 groups of front-reinforced and 5 groups of back-reinforced the small area ellipsoid defective steel plate. Discussed the reinforcement effect whether are the same both the front-reinforced and the back-reinforced. And the influence law was obtained on defect depth to the reinforcement effect. Test results show that: the defect surface strengthening and non defect surface strengthening both can improve the yield bearing capacity of the component. And the enhancement effect of defect surface reinforcement is better than that of non defect surface reinforcement. But the effect is not significant for the ultimate bearing capacity of the component.

From the perspective of structural design, a variety of vibration performances are summarized, and the applicability of two different vibration control methods is addressed. The engineering demands and design method of hybrid application of tuned dampers and viscous dampers in super tall buildings are fully investigated in this study. A super tall building project of more than 700m is employed to illustrate the combined application of viscous toggle-brace-damper and tuned damper in controlling the wind induced acceleration at the top.

In order to meet the security and applicability requirements of building structures at minimal costs, the optimal design is attracting increasing interest in the building industry, especially for tall building structures. One of optimization tools is sensitivity analysis, which helps engineers decide which structural members need to be changed. Currently, the main sensitivity analysis method is deriving formulas to calculate the sensitivity coefficient of optimization variables to design constraints, which is based on theoretical relationships between optimization variables and constraints. This paper will propose a new sensitivity analysis method- constant incremental sensitivity analysis (CISA) method. CISA method is straightforward in principle and can be applicable to arbitrary design constraints. The structural members are divided into several groups appropriately and each time one component group increases same amount of steel and the value of design constraint will be computed. In this way, engineers are able to know which component group is more sensitive to the design constraint. In this paper, different sensitivity analysis methods are used in a 3-story frame to validate the proposed method. And this sensitivity analysis method will be used in the optimal design for a real tall building project.

Spinning process has been widely applied in national defense and civilian field in recent years. The shape of spinning products are more and more complex and the requirement for formation quality are stricter. The completion of high-quality spinning products has become a difficult problem for spinning workers. The formation quality of processing products cannot be improved effectively until the mechanical structure of spinning equipments, processing possibility and processing characteristics are fully understood.

With more requirement for formation quality of cylindrical spinning products, the improvement for formation quality of spinning products has become a difficult problem with spinning workers. The formation quality of spinning products has much to do with the setting of process parameters. In order to set the spinning process parameters reasonably and improve the formation quality, the characteristics of spinning process parameters must be well understood.

Charge pump phase-locked loop(CP PLL) has been widely used in the clocking and data recovery. A high performance design of CP PLL is presented in this paper. It is fabricated in SMIC 0.18μm CMOS process. To reduce noise, the design uses a modified differential charge pump with a large swing, which can effectively inhibit the phase-locked loop output spectrum spurious. A CML oscillator is used, which has lower phase noise and jitter. By changing the difference between the high speed circuit path and low speed circuit path, the delay time of the tuning unit is changed. What’s more, the switched capacitor technology is applied to achieve a wider tuning range. The frequency range of the CP PLL is from 1GHz to 3.1GHz. The phase noise is -107dBc@1MHz and the RMS jitter is 1.725ps at the frequency of 2GHz.

Based on the wave theory, according to the heterogeneous structure of impedance characteristics and the principle of wave-mode transformation, this paper proposes a scheme that laying a layer of Hyper-elastic coating on the surface of a warship. Using the finite element method(FEM) for one-dimensional stress wave transmission characteristics in the cover structure to conduct the numerical simulation study of ship structure, the results of the numerical analysis show that due to the presence of such super-elastic covering layer cavity structure, comparing the impedance of cover layer air cavity with the impedance of the super-elastic solid rubber material, there is the phenomenon of impedance-unmatched which can lead to influence the stress wave propagation. And it is manifested in details that when subjected to shock loading, the cavity structure with a cover layer can affect the distribution of stress in the structure meanwhile it can make the shock wave being much consumed during the process of propagation in the medium, dissipated more energy and this structure can play an outstanding role in shock resistance as well.

The dynamic model of dual-rotor supported on floating-ring squeeze film dampers was established. The coupling effect between the elastic support and floating-ring squeeze film damper and between two rotors of the dual-rotor was considered in the model. Dynamic characteristics of the dual-rotor system are analyzed in making use of the finite element method. The results shown that the unbalance responseamplitude of dual-rotor supported on floating-ring squeeze film dampers can be effectively restrained when the dual-rotor work in critical speed and the floating-ring squeeze film dampers have little impact on the value of critical speed. The simulation results were validated with the experiments of the dual-rotor supported on dampers.

The static strength analysis of a diaphragm coupling with joint bearing is carried out by using ANSYS, we find that the diaphragm coupling can bear the force with only 1.5 times the maximum torque, 13228 rpm rotational speed or 12 mm compensation respectively, it can be used safely; when the diaphragm coupling is forced with combined loads(with 2000 N axial force), the coating of diaphragm coupling forced more than compression limit, there are security risks; when the diaphragm coupling is forced with combined loads(with less than 1850 N axial force), it can be used safely.

B₄C-LaB₆ porous composites are prepared by hot pressed sintering, and mechanical properties and microstructure of B₄C-LaB₆ porous composites were tested. The results show that Flexibility strength of B₄C-LaB₆ porous composites is greatly improved compared with that of monolithic porous boron carbide. B₄C react with La₂O₃ to completely form LaB₆ in porous composites. LaB₆ particles in B₄C grain boundary are produced by in-situ reaction. The presence of LaB₆ reinforcing particles could also suppress growth of B₄C grains which normally leads to improved strength.

Structural and bandgap properties of Be_xZn_1-xO alloy films were investigated by first-principles calculations. The alloy phase segregation caused by large lattice distortion and bowing parameter was predicted at intermediate Be content and was latterly confirmed by X-ray diffraction (XRD) measurement. In the case of the phase segregated BeZnO, two absorption edges, a weak absorption shoulder and a near band edge absorption, were observed in our calculated optical absorption spectra. The shoulder absorption trends to be eliminated by suppressing the phase segregation of BeZnO. By the further study on detailed density of states (DOS), the weak non-band-edge absorption shoulder is essentially originates from the electrons transferring from the 2p orbitals of oxygen atoms nearby the grain boundary between ZnO and BeO crystallites to the 4s orbitals of all of Zn atoms in the system. Such optical absorption spectra features provide a new phenomenon and mechanism in the novel alloy system BeZnO.

The macro-properties of roller compacted concrete (RCC) with high dosagelow quality fly ash are investigated, including strength, elastic modulus, ultimate tensile strain, drying shrinkage, autogenous deformation and durability, The properties of RCC containing 60% or more ground fly ash meet the design requirement. The results indicate that High dosage of low quality fly ash in RCC reduces the relative cement content, leading to a decrease of CH formation, which is the main hydration product to stimulate the second reaction of fly ash, lowering compressive strength at early age consequently. Before 90 days, the growing speed of ultimate tensile strain is fast and the values of the 3 RCCs reach around 80 με. Hereafter, the ultimate tensile strain still improves, and reaches to 90 με at 180 days and become steady after. The drying shrinkage of RCCs increases with the increase of W/B and reduces obviously by adding fly ash, and aggregate can effectively constrain drying shrinkage, autogenous deformation of RCC presents shrinkage tendency and decreases with the increase of fly ash dosage.

CATIA software is used to build two-dimensional and three-dimensional model of LNG storage tank, hexahedral meshes are generated in HYPERMESH software and ANSYS software is imported to analyze overall temperature field and thermal stress distribution of 30000m³ LNG storage tank. According to analysis result file, the distribution regularities of temperature and thermal stress of 30000 m³ LNG storage tank is concluded, key control points of cold insulation construction of LNG storage tank are highlighted, management of quality of cold insulation construction of LNG storage tank is tightened up and LNG construction level is upgraded.

In order to further improve the surface performance of the thin-walled precise roller bearing, there is still a need to resolve the problem of wear and fatigue induced by thin-walled precise roller bearing’s surface strengthening method. Therefore, it is necessary to review current achievements systematically and intensively. The basic principle and the advantages and disadvantages of several surface strengthening methods of thin-walled precise roller bearing are analyzed. Research status in the related fields are summarized. The development trends of surface strengthening method are predicted to improve the reliability and service life of thin-walled precise roller bearing.

Casing is one of the most used pipes in oil and gas exploration. The casing string, on the one hand, needs to bear large tensile loads generated by its weight. On the other hand, it needs to withstand great internal and external pressures. Tensile loads of the casing connection are being transmitted by its screw thread and sealing function on the fluid is achieved mainly by the interference fit of interior and exterior flank of thread. With the development of new exploration techniques, the exploitation and application of oil and gas wells under complex operating conditions such as deep wells, ultra deep wells, extended reach wells, horizontal wells and HTHP gas wells, urgently demand the premium connections with reliable sealing quality. The sealing performance of a casing premium thread under typical operating conditions using the finite element analysis method was analyzed. The effect mechanism of thread parameters on sealing property is obtained. The analysis results are of great significance on the structure optimization and improvement of air permeability performance of the premium thread.

Unique radiofrequency impedance and radiofrequency optical modulation spectroscopy methods for semiconductors and nonlinear-optical crystals investigation is proposed. Novel method, based on equivalent temperature concept, for determination of surface temperature distribution of crystal interacting with laser radiation is introduced.

For the parameters reverse of the aluminum alloy material constitutive equation and the obtainment of the stress value of non-experimental strain range, the corresponding correction principles and methods were proposed. The constitutive equation parameters were calculated based on NSGA-II algorithm through the dynamic drop test, the static tensile test and simulation, of which the test results showed its high accuracy.

A thin-walled beam with trapezoid cross-section was used as a prototype to design a three-point bending model, which to be evaluated by the peak force, SEA and the average force. Then the samples were selected by Latin Hypercube and were analyzed by FEM to establish a response surface approximate model about the section parameters and bending behavior. A optimization function was designed and SQP optimum method was utilized to find the optimal solution. The result shows that the optimization has improved the bending behavior of the beam with trapezoid cross-section which will provide information for the design of beam section.

Through static mechanical experiment about the compressive properties of the concrete mixed with silica fume and fly ash, the paper finds that when the ratio of water and cement is at 0.3 and the addition of silica fume is less than 16%, the compressive strength of silica fume concrete is improved with the increase of silica fume. While, when the addition of silica fume is more than 16%, the compression strength of silica fume concrete is decreased with the addition of silica fume, moreover when the addition of silica fume is 5%, the compressive strength of 7d and 28d concrete has been increased by 22.7% and 23.9% compared with concrete without adding of it. However, with the addition of fly ash at a range of 5% to 15%, the early strength of concrete is slightly improved according to the horizontal comparison.

Through SHPB dynamic impact test, the dosage of silicon powder and fly ash in the concrete was researched, then the paper studied silicon powder and fly ash content on the effect of dynamic mechanical properties of concrete. The results showed that: For concrete with ash only, under the low, immediate and high strain rate, the 15% dosage is best, the top stress of the concrete under 0.5MPa reach 155.1MPa. For concrete with silicon powder only, the 16% dosage is best, the top stress of the concrete under 0.6MPa reach 190.6MPa, twice the static compressive strength, and improve the resistance to impact of the plain concrete by 27%.

Stochastic topology optimization of continuum structure is studied, in this paper, considered the influence of random factors, all variables are in form of random variable in the process of calculation. Based on assuming random variables with normal distribution, linear congruential random number generators (LCGs) and transform method is employed to get pseudo-random. The random variable is separated into determined part and stochastic part, then substituted into the finite element analysis, eventually obtained element stress. The k nearest neighbor method is used to stochastic topology optimization. Finally, the feasibility of this approach is verified by several numerical examples.

Plate shape TA2 alloys were joined by vacuum electron beam welding(EBW) method. The microstructures of the joint shown that a few agglomerate β phase appear in seam zone beside dominating α phase, the heat affect and the seam zone had coarse texture compared with the base metal. Distribution of abnormal phase in the seam zone increased the local mechanical property and resulted bad corrosion resistance, because homogenous α phase has higher electric potential than abnormal phase. The tensile property of the joint shown that the joint broke at the base metal instead of the fusion zone, the fracture type shown ductile dimple fracture pattern, and the elongation of the sample is over 24% as that of the bulk titanium alloys.

There are the theoretical researches on a planetary transmission wrench, which has three stages transmission of type NGW. In order to minimize the wrench volume, a mathematical model is established on its design parameters. Actually, solving the model is a problem of mixed discrete variable optimization. According to different constraint condition, the model had been solved by a mixed method of discrete variable optimization and the second optimization. Through the example calculations, it proved that the method can be used to solve this kind of mixed discrete variable optimization problems, it will help to improve the optimization reliability and to give reference for structure optimization and cost controlling.

High densities with low voltage coefficients of capacitances (VCCs) of Metal-insulator-metal (MIM) capacitors are required for the application of radio frequency and analog/mixed-signal integrated circuits. In this paper, the MIM capacitors with SiO₂-HfO₂-SiO₂ (SHS) sandwiched dielectrics structures are fabricated. The results indicate that with the proper combination, the SHS dielectrics exhibit high capacitance while remaining relatively low VCCs. For the 1.5 nm individual SiO₂ layers, the MIM capacitor can offer a capacitance density of 9 fF/£m², quadratic voltage coefficients of capacitance of 436 ppm/V², and a leakage current as low as 2.3×10⁻⁸ A/cm² at 1 MV/cm.

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