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This paper examines the influence of porosities on the flexural and free vibration response of functionally graded material (FGM) plates based on the authors’ recently developed non-polynomial higher-order shear and normal deformation theory. The theory accommodates the nonlinear variation in the in-plane and transverse displacements in the thickness coordinates. It also contains the hyperbolic shear strain shape function in the displacement field with only four unknowns. A new mathematical model has also been proposed to incorporate the effects of porosity in the FGM plate. Various numerical examples have been solved to ascertain the accuracy, efficiency, and applicability of the present formulation. The effects of porosity, volume fraction index, plate thickness, aspect ratio, boundary conditions and temperature have been discussed in details. The obtained results can be treated as a benchmark for future studies.

There is a paucity of information on conditioning factors that hinder or promote adoption of multiple climate-smart practices and on the synergies among such practices in increasing household resilience by improving agricultural income. This study analyzes how heat, rainfall, and rainfall variability affect farmers’ choices of a portfolio of potential climate smart practices — agricultural water management, improved crop seeds, and fertilizer — and the impact of these practices on farm income in the Nile Basin of Ethiopia. We apply a multinomial endogenous switching regression approach by modeling combinations of practices and net farm income for each combination as depending on household and farm characteristics and on a set of climatic variables based on geo-referenced historical precipitation and temperature data. A primary result of this study is that farmers are less likely to adopt fertilizer (either alone or in combination with improved varieties) in areas of greater rainfall variability. However, even when there is high variability in rainfall, farmers are more likely to adopt these two yield-increasing inputs when they choose to (and are able to) include the third part of the portfolio: agricultural water management. Net farm income responds positively to agricultural water management, improved crop variety or fertilizer when they are adopted in isolation as well as in combination. But this effect is greater when these practices are combined. Simulation results suggest that a warming temperature and decreased precipitation in future decades will make it less likely that farmers will adopt practices in isolation but more likely that they will adopt a combination of practices. Hence, a package approach rather than a piecemeal approach is needed to maximize the synergies implicit in various climate smart practices.

The paper used the moving element method (MEM) to analyze the dynamics of the functionally graded material (FGM) plate under the moving load considering the effect of temperature. To calculate the displacement of the plate, the study applied the Mindlin plate theory. A nine-node isoparametric element, each with five degrees of freedom, is used to model the plate element. According to the MEM, the equation of motion of the FGM plate is established based on the principle of virtual work and on a coordinate system that moves along with the moving load. The temperature field is assumed to be constant in the plane and varies across the plate thickness. By solving the governing equation of temperature transfer, it is possible to obtain a temperature distribution function. Both mechanical strain and temperature-induced strain are considered to determine plate strain. Numerical results were surveyed with different parameters and compared with published results to verify the reliability of the model. It is found that temperature significantly affects the dynamic response of the FGM plate. This study shows that the displacement of the plate increases when the temperature increase.

In this work, we demonstrate the sensing principle to simultaneously detect the salinity and temperature of seawater using a 1D-defective photonic crystal structure. We designed a one-dimensional defective mode photonic crystal based on the well-known transfer matrix method (TMM) for detecting the seawater salinity and temperature. Our proposed optical sensor is based on the following concept. Since the concentration of the salinity in the seawater changes the refractive index of the seawater, the sensitivity can be calculated by a peak wavelength shift happening in the output transmission spectrum for its variation of different concentration of samples. By adjusting the design parameters of our proposed structure such as the thickness of the defect layer, the temperature and the salinity, we investigated the corresponding optical properties response where the resulted transmittance peak can be turned over the considered range.

In this study, compounds of B₆Si were irradiated using a ${}^{60}$Co gamma source that have an energy line of 1.25 MeV at the absorbed dose rates from 14.6 kGy to 194.4 kGy. Surface morphology images of the sample obtained by Scanning Electron Microscope (SEM) show that the crystal structure at a high absorbed doses $(D\ge 145.8\mathrm{\text{kGy}})$ starts to be destroyed. X-ray diffraction studies revealed that with increasing radiation absorption dose, the spectrum intensity of the sample was decreased 1.96 times compared with the initial value. Thermal properties were studied by Differential scanning calorimetry (DSC) method in the temperature range of 30–1000${}^{\circ }$C.

The impact of shape, size and temperature on elastic properties of nanomaterials is studied in this work. We have extended the melting temperature expression for nanostructures formulated by Guisbiers et al. and obtained the expression of elastic moduli and thermal expansivity for nanomaterials. An isobaric Tait equation of state is combined with Guisbiers model and the model so obtained is applied to analyze the shape, size and temperature effect on Young’s modulus and thermal expansivity in nanomaterials. The present computed results are compared with the simulated results and available experimental data. The Young’s modulus is observed to decrease as particle size is reduced while thermal expansivity increases with decrease in the size of nanomaterial. The Young’s modulus shows decrease with increase in temperature and decrement is observed maximum in spherical nanomaterials and minimum in nanofilms (NFs). Rate at which modulus is decreasing is found to increase as particle size is reduced. Good consistency of present predicted results with the available theoretical and experimental data is observed. The present calculated results are thus found consistent with the general trend of variation.

In this paper, nanoparticles of cobalt oxide (Co₃O${}_4)$ are prepared at different temperatures $120^{\circ }$C, $140^{\circ }$C and $160^{\circ }$C using the hydrothermal method. Cobalt nitrate hexahydrate: Co (NO${}_3{)}_2\cdot 6$H₂O is used as precursor and potassium hydroxide (KOH) is used as precipitating agent. Particle size is controlled using precursor concentration. It is also investigated in this research that particle size increases at high-temperature. Nanoparticles of size between (13.62–17.81 nm) are obtained using this technique (Hydrothermal method). SEM results provide nonuniform distribution of nanoparticles with sharp grain boundaries. Electrical characterization confirms the semiconducting behavior of the material as resistivity decreases with increase in temperature. Electrochemical measurements show detection of hydrogen peroxide H₂O₂ by nanoparticles of Co₃O₄.

The drilling of glass fiber-reinforced plastic (GFRP) composites gained importance since they are used as structural components in many industries such as automotive, aerospace, and aviation. A large number of holes are needed in the industry to join these composite parts. However, some failures occur in drilling GFRP composites, such as delamination, matrix cracking, and fiber breakage. These failures not only reduce the strength of the composite, but also reduce its service life. Drilling parameters, drill bits, and woven types have a great influence on the occurrence of these failures by greatly influencing the thrust force, surface quality, and cutting temperature. In this study, the effects of drilling parameters and woven types of GFRP composites on thrust force, surface roughness, delamination factor, and cutting temperature were examined in the drilling of uni-directional (UD), $\pm 45^{\circ }$ and 0${}^{\circ }∕90^{\circ }$ GFRP woven composites. The effects of drilling parameters and the delamination factor on the tensile strength of the drilled specimen were also investigated. The result of this study indicated that thrust force, delamination factor, and surface roughness increased with increasing cutting speed and feed rate. An increase in feed rate decreased the cutting temperature, while an increase in cutting speed increased the cutting temperature. Also, it was found that the delamination factor had a critical influence on the tensile strength of the GFRP composites.

To use supplying gases and energy resources efficiently, accurate measurement of irregular gas is necessary. The TDLAS (Tunable laser absorption spectroscopy) technique can be used to control and monitor the supplying gas conditions and combustion of industrial processes. Recently, CT-TDLAS (Computed tomography-tunable diode laser absorption spectroscopy) has been developed to measure the temperature and concentration field of gases. In this study, the 2-dimensional temperature distribution of the Propane-Air premixed flame in several mixing conditions of fuel has been measured by the constructed CT-TDLAS system. 2-Dimensional temperature distributions are measured by 16 path cells. Further, the third-order polynomial regression analysis was applied to resolve the absorption spectra from the incident and transmitted light for a particular gas. The SMART (simultaneous multiplicative algebraic reconstruction technique) algorithm has been adopted for reconstructing the absorption coefficients on the detecting area. As a result of comparing the temperature for the 2-dimensional detecting area using the thermocouple and CT-TDLAS technique, it has been verified that the relative error for the temperatures measured by the thermocouples and calculated by the CT-TDLAS was up to 8%.

ZnFe${}_{1.96}$La${}_{0.04}$O₄ nanocrystalline powders were synthesized by auto-combustion with the aid of glycine as fuel. The synthesized powders were subjected to heat treatment in air at constant temperatures (600–970${}^{\circ }$C) for a period of 2 h. The annealed powders were characterized by X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and UV–Vis–NIR spectroscopy. The as-synthesized and annealed powders formed spongy porous network structure with voids and pores. All the powders were found to be single phase nanomaterial with cubic spinel crystal structure and the desired composition; however, they contained strains, dislocations and lattice distortions. Some of these strains and dislocations are relaxed as a function of annealing temperature. The powders displayed direct and indirect optical band gaps. The energies of these band gaps were found to vary as a function of the induced strains and dislocations. It is suggested that the energy of the optical band gap in lanthanum-doped zinc ferrite nanocrystalline powders can be varied as a function of induced strains if the initial preparation conditions and the following heat treatments are controlled.

Bone drilling is a common procedure in Medicine, mainly in traumatology and orthopedic procedure for fractures fixation and in reconstructive surgery. The success of this surgical procedure is dependent on many factors, namely, on heat generation control during the bone drilling. The main concern in bone drilling is the mechanical and thermal damage of the bone induced by inappropriate parameters such as drill speed and feed-rate during the drilling. This study focuses on the temperature generated during drilling of cortical bone tissue (bovine origin) and solid rigid polyurethane foams with similar mechanical properties to the human bone tissue. Different parameters such as drill speed, feed-rate and hole depth were tested. All results showed that improvement of the drilling parameters and the drill temperatures can be estimated. It was concluded that when the drill speed and feed-rate were higher, the bone temperature increase was lower. The obtained results of temperature in the drilling process of polyurethane foam blocks or bovine bone were compared with a good agreement in between both.

We study the redistribution of mobile charge carriers in a composite fiber of piezoelectric dielectrics and non-piezoelectric semiconductors in extensional deformation under a uniform temperature change. The macroscopic theory of piezoelectricity and the drift-diffusion theory of semiconductor are used, coupled by doping and mobile charges. A one-dimensional model for extension is developed. Through a theoretical analysis, it is shown that under a temperature change the mobile charges in the semiconductor redistribute themselves under the polarization and electric field produced through thermoelastic, pyroelectric and piezoelectric effects. The results suggest the possibility of using composite structures for thermally manipulating mobile charges in semiconductors and have potential applications in piezotronics.

In this study, we assess the future changes in minimum temperature (T-min), maximum temperature (T-max), and precipitation (PRCP) for the three periods the 2020s (2011–2040), the 2050s (2041–2070), and the 2080s (2071–2100), with respect to the reference period 1981–2010 over Algeria focusing on a validation of the Statistical DownScaling Model (SDSM). In this approach, to underpin our analysis, we evaluate statistically the SDSM performance by simulating the historical temperatures and precipitation. The NCEP reanalysis data and CanESM2 predictors of three future scenarios, RCP2.6, RCP4.5, and RCP8.5 are used for model calibration and future projection, respectively. The projected climate changes resulting from the application of SDSM show a convincing consistency with those unveiled in previous studies over Algeria based on dynamical regional climate model outputs conducted in the context of Middle East-North Africa region. By the end of the century, the results exhibit strong warming for both extreme temperatures under the worst-case scenario (RCP 8.5), it is more pronounced for the T-max and over the Algerian Sahara region. Under the optimistic scenario (RCP2.6), the strength of the warming is expected to increase for both extreme temperatures. The projected changes of precipitation revealed for all scenarios several discrepancies with significant decrease over the northwest region and central Sahara, while nonsignificant change is projected for the center and eastern coastal regions. Our findings corroborate previous studies using sophisticated tools by demonstrating that Algeria’s climate is expected to warm further in the future. These primary findings could give an overview of the application of the statistical modeling approach using SDSM over a semi-arid and arid vulnerable region like Algeria and would extend our knowledge in the climate-modelling field for the North Africa zone by providing an added value to the existing GCMs and regional climate projections. In addition, reliable information regarding the magnitude of future changes at local scale may be used in impact models to assess changes of other key economic sector variables such as water resources management, energy and agriculture.

This study examined both long-term and short-term trends and fluctuations in rainfall and temperature over 34 meteorological stations located at seven regions in Bangladesh. Descriptive statistical analysis and Mann–Kendall trend test were utilized to investigate the variability of the rainfall and temperature of all stations in Bangladesh. Our research gave some insights into Bangladesh’s rainfall and temperature trends and variability.

Bone grinding is a craniotomy procedure which is used to remove a bone flap from the skull to expose and create an access for the dissection of tumors. In this study, a computer-controlled neurosurgical bone grinding has been used to explore the effect of various neurosurgical bone grinding parameters, such as cutting forces, torque, grinding force ratio, and temperature generated during bone grinding have been investigated. Bone samples after grinding have been assessed for morphological analysis. Based on the outcomes, a multi-attribute decision-making methodology based on grey relational analysis has been adopted. Regression models have been developed and then validated to ensure the adequacy of the developed models. Subsequently, a comparative analysis of experimental and predicted results have been presented. It is revealed that grinding forces and torque decreased with the escalation of rotational speed from 35,000 revolutions per minute (rpm) to 55,000rpm. The optimum combination of process parameters found as rotational speed of 55,000rpm, feed rate of 20mm/min, and depth of cut of 0.50mm.

The use of continuous welded rails (CWR) is increasingly common and is particularly important when it comes to high-speed ballasted tracks. As the longitudinal displacements are restricted in CWR tracks, a considerable rise in temperature induces compressive stresses in the rails that can lead to track buckling. Given the nonlinear behavior of the ballast, usually represented by a linear plastic model, the problem of snap-through buckling may occur, for which only a few nonlinear analysis methods can trace the full response of the track structure. However, these methods fail to yield convergent solutions for problems with thermal loads when implemented in their conventional algorithm. For this reason, a new methodology is presented allowing the calculation of the safe temperature. In addition, some analytical results are also derived for comparison with the numerical results, obtained using three-dimensional finite element beam models provided by ANSYS.

There is a substantial concern for the economic impacts of global warming. This study identifies the effects of seasonal temperatures on total economic output in the cities of China, and then projects the changes in local economic performance under future climate and development scenarios. The results suggest that there are significant negative effects of warm seasonal temperature but positive effects of cold seasonal temperature on economic growth. These different effects increase as more lags of temperature are included. By 2090, the cities may have the average reduction of 44% in GDP per capita under RCP8.5, but some of them in Northeast China are predicted to get positive impacts under RCP2.6. The difference in the estimated aggregate impacts under the two RCPs could be as much as 24%. The poor cities are likely to have higher economic damages, which amplifies the economic inequality. Finally, the ranges of economic impacts projected by different climate models are presented.

Every year there are as many as 20,000 scientific papers and reports published about the science of climate and climate change, and the resulting impacts and policy implications. The vast majority of these publications are rigorously done and are peer reviewed before publication, Since about 1990, on a time scale of roughly every 4–6 years, top experts are being asked to assess the state of the science and the implications of the changes occurring in the climate. Internationally, this occurs through the Intergovernmental Panel on Climate Change (IPCC), and for the United States, through the US National Climate Assessments (NCAs). These assessments provide important input to policy considerations, at international, national, and local levels…

The temperature dependent binding energy of some low lying excited states for a compositional Quantum Well have been calculated for various impurity locations by extending the investigation of Elabsy.⁴ It has been observed that the temperature plays an important role in the binding energy of low lying excited states also.

This paper is to investigate the dispersion relation and decay rate of plasmon modes in a double layer system made of monolayer graphene (MLG) and infinite GaAs quantum well at finite temperature within the generalized random-phase-approximation and taking into account the 2DEG layer-thickness and the inhomogeneity of the background dielectric. Calculations demonstrate that when the quantum well width increases, the acoustic (AC) plasmon frequency decreases dramatically, but the optical (OP) one seems unchanged. In addition, the results also illustrate that the temperature and separated distance affect significantly both AC and OP plasmon modes of the system. Finally, the dielectric of the background acts strongly on the OP plasmon curve while carrier density in two layers and exchange-correlation effects only lead to remarkable changes for the acoustic one.