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A LCD glass plate is supported by multi-pins and golf-tee type support. In the FEM analysis, the support condition is treated as a simply supported boundary condition. In this study, the optimization on the location of multi-simply support is conducted. The size optimization method of ANSYS 8.0 is used as the optimization tool to search for the optimal support location of LCD glass plate. In the manufacturing process, the support condition is a fatal factor of quality control of LCD production. From the results of optimization, deflection decreases 51% compared with the original model.

This study investigates the behaviors of simply supported reinforced concrete (RC) beams subjected to impact loads. A numerical model of RC beams has been calibrated and a total of 18 RC beams with varying longitudinal reinforcement, transverse shear reinforcement, span and effective depth are investigated, subjected to different input impact energy. It is found that inertia force plays an important role in resisting an impact load at the starting time. The slenderness of the beam can cause increased downward reaction force and also amplifies the upward reaction force. Based on the numerical results, recommendations are made for designing RC beams under low velocity impact load. A formula is derived to predict the maximum mid-span deflection under low velocity impact load with respect to the kinetic energy and static bending capacity. The maximum spacing and the diameter of stirrups are also recommended so as to avoid the brittle failure under impact load.

This study attempts to propose innovative multi-layer cement-based composites to have high impact resistance which could be used for runway. In this paper, the performances of two innovative multi-layer composite runway pavements using asphalt concrete-high strength concrete-cement-treated aggregate and asphalt concrete-high strength concrete-cement mortar in surface-base-subbase layer were evaluated under impact loads. ABAQUS/Explicit software was used to simulate loading condition and nonlinear stabilized runway pavement layers characteristics. In addition, a detailed parametric study was also carried out to explore the effects of the selected materials and load-related parameters in changing the performance of multi-layer composites. The findings of the study will be helpful to introduce protective multi-layer composite runway pavement and consequently to reduce the maintenance work of runway pavement.

The deflection of the beam estimated from modal flexibility matrix (MFM) indirectly is used in structural damage detection due to the fact that deflection is less sensitive to experimental noise than the element in MFM. However, the requirement for mass-normalized mode shapes (MMSs) with a high spatial resolution and the difficulty in damage quantification restricts the practicability of MFM-based deflection damage detection. A damage detection method using the deflections estimated from MFM is proposed for beam structures. The MMSs of beams are identified by using a parked vehicle. The MFM is then formulated to estimate the positive-bending-inspection-load (PBIL) caused deflection. The change of deflection curvature (CDC) is defined as a damage index to localize damage. The relationship between the damage severity and the deflection curvatures is further investigated and a damage quantification approach is proposed accordingly. Numerical and experimental examples indicated that the presented approach can detect damages with adequate accuracy at the cost of limited number of sensors. No finite element model (FEM) is required during the whole detection process.

The paper discusses the relationship between learning, innovation and (institutional) reflexivity. It is often held that reflexivity is a crucial factor for learning and innovation processes. However, a rather formalistic approach to reflexivity is predominant. We propose to overcome this limitation and to develop a more meaningful concept of reflexivity which "reflects" the contingent, relational, dynamic and complex character of organizational environments and reality. Based on this broadened understanding it appears that reflexivity is imminently a dialectic category and, under specific circumstances, it can also inhibit innovation. This is especially the case when reflexive tools are abused to push performance only. In order to illustrate our concept and hypotheses we added two case studies which highlight the conflicting counterparts of reflexivity and innovation and pointed us to important cultural "success factors".

This paper presents experimental results of S-glass fabric prepreg composite material to determine the compressive strength of uncertain S-glass fabric prepreg coupons along warp and weft direction at room temperature environment. A coupon is a small sample of the material under test that has been prepared in such a way that the failure mechanism will be representative of the larger production. Universal testing machine (UTM) was used for experiment. One of the hydraulic grips was fixed on the crosshead and the other grip was fixed on the hydraulic piston of the UTM. A load cell was provided on the crosshead for measuring the applied load. Uncertainty in the manufacturing process of S-glass is very important. Reducing the rejection rate of parts by selecting the right reinforcement, matrix and controlled process during the manufacturing process is very important which ensures the quality and performance of the manufactured parts as per application.

Modeling and nonlinear stress analysis of piezolaminated CNTs/fiber/polymer composite (CNTFPC) plates under a combined mechanical and electrical loading are investigated in this study. The governing equations of the piezoelectric CNTFPC plates are derived based on first-order shear deformation plate theory (FSDT) and von Kármán geometric nonlinearity. Halpin–Tsai equations and fiber micromechanics are used in hierarchy to predict the bulk material properties of the multiscale composite. The CNTs are assumed to be uniformly distributed and randomly oriented through the epoxy resin matrix. An analytical solution is employed to determine the large deflection response and stress analysis of the nanocomposite plates. Finally, by solving some numerical examples for simply supported plates, the effects of the applied constant voltage, plate geometry, volume fraction of fibers and weight percentage of SWCNTs and MWCNTs on the deflection and stress analyses of the piezoelectric CNTs/fiber/polymer multiscale composite plate are studied. It is shown that the deflections significantly decrease with a small percentage of CNTs. Also, it is found that the SWCNTs reinforcement produces more pronounced effect on the bending and stress of the nanocomposite plates in comparison with MWCNTs.

Based on the elastic fracture mechanics, we establish a continuous model of one-dimensional Euler–Bernoulli cracked beam using the traveling wave method, and analyze the damage characteristics of cracked beam through the changes of deflection and power flow response. First, the control equation of bending vibration of healthy beam is deduced by traveling wave method. Then, the reflection and transmission matrices of waves at force point, constraint point, crack point are derived. The analytic solutions of deflection and power flow are expressed explicitly as the function of crack location and size. The effects of crack width and depth on deflection and power flow response of cracked beam are revealed. Finally, the numerical example illustrates the effectiveness of the proposed method.

Herein, the deflection and instability of a freestanding carbon nanotube (CNT) probe/sensor in the vicinity of the graphene layers are investigated. A nanoscale continuum model is employed to obtain nonlinear constitutive equation of freestanding CNT. The van der Waals attraction is computed from the simplified Lennard-Jones potential for two common engineering cases including large and small number of graphene layers. Four approaches, i.e., approximated function, homotopy perturbation method, lumped parameter model and numerical analysis, are employed to solve the governing equation of CNT. The intermolecular force-induced deflection, minimum initial gap and stable length of freestanding CNT are determined. The analytical results agree well with the numerical solutions.

Because fine needles can easily be deflected, accurate needle insertion is often difficult. Lower abdominal insertion is particularly difficult because of less imaging feedback; thus, an approach for allowing a straight insertion path by minimizing deflection is beneficial in cases of lower abdominal insertion. Although insertion with axial rotation can minimize deflection, the rotational insertion may cause tissue damage. Therefore, we established a novel insertion method for minimizing both deflection and tissue damage by combining rotation and vibration. Using layered tissues, we evaluated the effect of a combination of rotation and vibration in terms of deflection and tissue damage, which were measured by the insertion force and torque, and the area of the hole created by the needle using histological tissue sections to measure tissue damage. The experimental results demonstrated that insertion with unidirectional rotation is risky in terms of tissue wind-up, while insertion with bidirectional rotation can decrease deflection and avoid wind-up. We also found that insertion with vibration can decrease the insertion force and torque. Therefore, insertion with a combination of bidirectional rotation and vibration can minimize needle deflection and tissue damage, including the insertion force and torque and the hole area.

The following article has been written primarily by the high school students who make up the team “Cryptic Ontics”, one of the two winning teams in the 2018 edition of CERN’s Beamline for Schools (BL4S) competition, and is based on the set of experiments the students endeavoured to conduct over the course of a two-week period at CERN.

Reconstructing influential physical theories from scratch often helps in uncovering hitherto unknown logical connections and eliciting instructive empirical checkpoints within said theory. With this in mind, in the following article, a top-down reconstruction (beginning with the experimental observations and ending at the theoretical framework) of the Lorentz force equation is performed, and potentially interesting questions which come up are explored. In its most common form, the equation is written out as: $F=qE+q(v\times B)$. Only the term that includes the magnetic field $q(v\times B)$ will be dealt with for this article. The independent parameters we use are (i) the momenta of the particles, (ii) the charge (rather, the types) of particles, either positive or negative, and (iii) the current passing through the dipole generating the electromagnetic field. We then measure the angle by which particles get deflected while varying these three parameters and derive an empirical relationship between them.

In machining, slender bar is a kind of shaft parts which is difficult to process. Because of its low radial rigidity, it is easy to bend under cutting force when in ultrasonic vibration turning or ordinary turning. The article builds model of slender bar deflection and proceeds numerical simulated analysis based on the model. Ultrasonic vibration turning system is built and the relative experiment is preceded. Then the influence of different parameters on the deflection of slender bar will be obtained.

Based on ABAQUS software, the pin connection between aluminum alloy templates simulated using MPC PIN element and spring element (Springs 2), and the deflection of aluminum alloy template simulated during the concrete placement process. Comparing with the results of simplified calculation, the analysis results of the finite element show that the finite element modeling of aluminum template with MPC PIN element and spring element (Springs 2) as well as the analysis results can be used as reference for the engineering application of aluminum alloy template.