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21 – 30 of over 5000Pankaj V Katariya and Subrata Kumar Panda
The purpose of this paper is to develop a general mathematical model for laminated curved structure of different geometries using higher-order shear deformation theory to evaluate…
Abstract
Purpose
The purpose of this paper is to develop a general mathematical model for laminated curved structure of different geometries using higher-order shear deformation theory to evaluate in-plane and out of plane shear stress and strains correctly. Subsequently, the model has to be validated by comparing the responses with developed simulation model (ANSYS) as well as available published literature. It is also proposed to analyse thermal buckling load parameter of laminated structures using Green–Lagrange type non-linear strains for excess thermal distortion under uniform temperature loading.
Design/methodology/approach
Laminated structures known for their flexibility as compared to conventional material and the deformation behaviour are greatly affected due to combined thermal/aerodynamic environment. The vibration/buckling behaviour of shell structures are very different than that of the plate structures due to their curvature effect. To model the exact behaviour of laminated structures mathematically, a general mathematical model is developed for laminated shell geometries. The responses are evaluated numerically using a finite element model-based computer code developed in MATLAB environment. Subsequently, a simulation model has been developed in ANSYS using ANSYS parametric design language code to evaluate the responses.
Findings
Vibration and thermal buckling responses of laminated composite curved panels have been obtained based on proposed model through a customised computer code in MATLAB environment and ANSYS simulation model using ANSYS parametric design language code. The convergence behaviour are tested and compared with those available in published literature and ANSYS results. Finally, the investigation has been extended to examine the effect of different parameters (thickness ratios, curvature ratios, modular ratios, number of layers and support conditions) on the free vibration and thermal buckling responses of laminated curved structures.
Practical implications
The present paper intends to give sufficient amount of numerical experimentation, which may lead to help in designing of finished product made up of laminated composites. Most of the aerospace, space research and defence organisation intend to develop low cost and high durable products for real hazard conditions by taking combined loading and environmental conditions. Further, case studies might lead to a lighter design of the laminated composite panels used in high-performance systems, where the weight reduction is the major parameter, such as aerospace, space craft and missile structures.
Originality/value
In this analysis, the geometrical distortion due to temperature is being introduced through Green–Lagrange sense in the framework of higher-order shear deformation theory for different types of laminated shells (cylindrical/spherical/hyperboloid/elliptical). A simulation-based model is developed using ANSYS parametric design language in ANSYS environment for different geometries and loading condition and compared with the numerical model.
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Rahul Priyadarshi, Srikanta Routroy and Girish Kant Garg
The literature review of post-harvest supply chain (PHSC) losses is carried out and analyzed in this paper followed by bibliometric analysis of the literature.
Abstract
Purpose
The literature review of post-harvest supply chain (PHSC) losses is carried out and analyzed in this paper followed by bibliometric analysis of the literature.
Design/methodology/approach
The literature survey is performed across various dimensions such as PHSC losses, PHSC risks and PHSC sustainability (waste management and waste reduction). One hundred thirty research articles during the period of 1989–2020 were considered for the review.
Findings
The PHSC losses have been identified in this literature survey. The calculation and mitigation strategies stated by various researchers in the literature are addressed. The important loss mitigation dynamics are also presented to reduce the PHSC losses and to improve food availability.
Research limitations/implications
The major focus is given on the PHSC of agriculture produces. However, research articles from fish and meat supply chain are excluded as they follow a different perishability curve.
Practical implications
The current work will add value to the agriculture supply chain literature, provide a platform for PHSC losses and provide assistance/guideline toward loss calculation, loss mitigation, improved rural employability, improved rural entrepreneurship and improved revenue generation.
Social implications
The performed research will assist the researchers, entrepreneurs and farmers to understand the current scenario of food wastage at different stages of the supply chain better. It will provide the guidelines for calculation and mitigation of various stated PHSC losses. This study will be helpful to enhance food availability and food security in post-coronavirus crisis.
Originality/value
The paper explores and highlights PHSC loss calculations and mitigation strategies to identify the postharvest loss situation and better utilization of fresh produces.
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Chunhui Huo, Muhammad Arslan Safdar and Misbah Ahmed
The increased interest of the industrial sector in sustainable concepts and leadership has lagged behind conceptual advancement. Leaders are increasingly being pushed to encourage…
Abstract
Purpose
The increased interest of the industrial sector in sustainable concepts and leadership has lagged behind conceptual advancement. Leaders are increasingly being pushed to encourage sustainable performance. In order to examine the relationship between responsible leadership and sustainable performance, this research creates a model based on the logic of RL performance, with the concurrent mediation of epistemic motivation and moderating role of sustainable climate.
Design/methodology/approach
The current research analyzed a sample of 520 respondents from employees recruited from public sector organizations in Pakistan who were full-time employees in Punjab province in three waves with an interval of two weeks in each wave. To collect data, the scales are adapted from past studies that were relevant to this study. The data received from the survey questionnaire are analyzed using SEM.
Findings
The study's findings demonstrate a significant as well as positive association between RL and SP with β = 0.298 and p < 0.001. Further, a significant mediating impact of epistemic motivation on the relationship between RL and sustainable performance with β = 0.238 and p < 0.001 is also evident. Epistemic motivation is an important mediator because transparency in knowledge held massive importance to get sustainable outcomes and is predominant factor to exert his/her efforts.
Practical implications
The research shows some theoretical and practical implications. To achieve the aims of sustainable development, organizations should first encourage responsible leadership behaviors. By establishing a shared vision and goals, top management can encourage responsible leadership techniques within their jurisdiction. In order to encourage responsible leadership behaviors, organizations should seek to create capacity at both organizational and social levels. It will change employee attitudes and provide the knowledge needed to achieve sustainable development objectives.
Originality/value
This is one of the initial studies to examine the relationship between responsible leadership and sustainable performance. Further, the concept of social exchange theory is used to understand sustainable performance from a comprehensive standpoint.
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With numerous and ambiguous sets of information and often conflicting requirements, construction management is a complex process involving much uncertainty. Decision makers may be…
Abstract
With numerous and ambiguous sets of information and often conflicting requirements, construction management is a complex process involving much uncertainty. Decision makers may be challenged with satisfying multiple criteria using vague information. Fuzzy multi-criteria decision-making (FMCDM) provides an innovative approach for addressing complex problems featuring diverse decision makers’ interests, conflicting objectives and numerous but uncertain bits of information. FMCDM has therefore been widely applied in construction management. With the increase in information complexity, extensions of fuzzy set (FS) theory have been generated and adopted to improve its capacity to address this complexity. Examples include hesitant FSs (HFSs), intuitionistic FSs (IFSs) and type-2 FSs (T2FSs). This chapter introduces commonly used FMCDM methods, examines their applications in construction management and discusses trends in future research and application. The chapter first introduces the MCDM process as well as FS theory and its three main extensions, namely, HFSs, IFSs and T2FSs. The chapter then explores the linkage between FS theory and its extensions and MCDM approaches. In total, 17 FMCDM methods are reviewed and two FMCDM methods (i.e. T2FS-TOPSIS and T2FS-PROMETHEE) are further improved based on the literature. These 19 FMCDM methods with their corresponding applications in construction management are discussed in a systematic manner. This review and development of FS theory and its extensions should help both researchers and practitioners better understand and handle information uncertainty in complex decision problems.
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Javad Gerami, Mohammad Reza Mozaffari, Peter Wanke and Yong Tan
This study aims to present the cost and revenue efficiency evaluation models in data envelopment analysis in the presence of fuzzy inputs, outputs and their prices that the prices…
Abstract
Purpose
This study aims to present the cost and revenue efficiency evaluation models in data envelopment analysis in the presence of fuzzy inputs, outputs and their prices that the prices are also fuzzy. This study applies the proposed approach in the energy sector of the oil industry.
Design/methodology/approach
This study proposes a value-based technology according to fuzzy input-cost and revenue-output data, and based on this technology, the authors propose an approach to calculate fuzzy cost and revenue efficiency based on a directional distance function approach. These papers incorporated a decision-maker’s (DM) a priori knowledge into the fuzzy cost (revenue) efficiency analysis.
Findings
This study shows that the proposed approach obtains the components of fuzzy numbers corresponding to fuzzy cost efficiency scores in the interval [0, 1] corresponding to each of the decision-making units (DMUs). The models presented in this paper satisfies the most important properties: translation invariance, translation invariance, handle with negative data. The proposed approach obtains the fuzzy efficient targets corresponding to each DMU.
Originality/value
In the proposed approach, by selecting the appropriate direction vector in the model, we can incorporate preference information of the DM in the process of evaluating fuzzy cost or revenue efficiency and this shows the efficiency of the method and the advantages of the proposed model in a fully fuzzy environment.
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Anand Kumar Yadav, M.S. Barak and Vipin Gupta
This paper aims to study the impact of pyro-electricity, moisture and temperature diffusivity on the energy distribution of plane waves at the free surface of an orthotropic…
Abstract
Purpose
This paper aims to study the impact of pyro-electricity, moisture and temperature diffusivity on the energy distribution of plane waves at the free surface of an orthotropic piezo-hygro-thermo-elastic medium.
Design/methodology/approach
This study presents the novel creation of governing equations for an anisotropic piezothermoelastic medium with moisture impact, which is a significant contribution of this paper.
Findings
In addition to providing numerical data for the amplitude ratios and energy ratios of reflected waves, this study identifies five different kinds of coupled reflected plane waves, namely, quasi-longitudinal P wave, quasi-thermal wave, quasi-transverse wave, quasi-moisture wave and electric potential wave.
Research limitations/implications
The graphical analysis examines the impact of various factors, such as the angle of incidence, moisture and temperature diffusivity, pyro-electricity and frequency, on energy distribution.
Practical implications
This paper's results significantly impact the development of more efficient piezoelectric materials and their applications in geophysics.
Originality/value
The authors of the submitted document initiated and produced it collectively, with equal contributions from all members.
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The purpose of this study is to construct and analyze a parameter uniform higher-order scheme for singularly perturbed delay parabolic problem (SPDPP) of convection-diffusion type…
Abstract
Purpose
The purpose of this study is to construct and analyze a parameter uniform higher-order scheme for singularly perturbed delay parabolic problem (SPDPP) of convection-diffusion type with a multiple interior turning point.
Design/methodology/approach
The authors construct a higher-order numerical method comprised of a hybrid scheme on a generalized Shishkin mesh in space variable and the implicit Euler method on a uniform mesh in the time variable. The hybrid scheme is a combination of simple upwind scheme and the central difference scheme.
Findings
The proposed method has a convergence rate of order
Originality/value
A class of SPDPPs of convection-diffusion type with a multiple interior turning point is studied in this paper. The exact solution of the considered class of problems exhibit two exponential boundary layers. The theoretical results are supported via conducting numerical experiments. The results obtained using the proposed scheme are also compared with the simple upwind scheme.
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Bethelehem Girma, Abonesh Taye, Wondimagegn Wondimu and Melese Sinaga
In spite of the vulnerability of prisoners to depression and their increased number, the issue has not been thoroughly investigated in Ethiopia. In particular, the determining…
Abstract
Purpose
In spite of the vulnerability of prisoners to depression and their increased number, the issue has not been thoroughly investigated in Ethiopia. In particular, the determining factors of depression have not been exhaustively identified. Thus, the purpose of this study is to assess the prevalence of depression and associated factors among prisoners in Mizan prison institute, southwest Ethiopia.
Design/methodology/approach
An institution-based cross-sectional study was conducted from April 6–27, 2020. A total of 340 randomly selected prisoners were included. Depression was assessed using the Patient Health Questionnaire-nine and participants were considered to be in a state of depression if they scored five and above. Binary logistic regression was used to assess the association between the outcome variable (depression) and the independent variables (factors). The odds ratio with a 95% confidence interval (CI) was used to measure the strength of association. The final significance was decided using a p-value < 0.05.
Findings
The prevalence of depression was 29.9% (95% CI: 25%, 34.8%). Prisoners whowere not participating in the duty work of the prison had 55% (adjusted odds ratio [AOR] = 0.45; 95% CI: 0.22, 0.93) less odds of depression compared to those who were participating in the duty work. Similarly, physically active respondents had 81% (AOR = 0.19; 95% CI: 0.10, 0.35) less odds of depression than physically inactive respondents. Moreover, undernourished participants had two times (AOR = 2.03; 95% CI: 1.08, 3.82) higher odds of depression than normal participants.
Research limitations/implications
Considering their risk of exposure compared to the general population and the limitations of cross-sectional study design, special care should be provided to the prisoners’ mental health. Moreover, priority attention should be given to the undernourished, physically inactive and those who are participating in duty work in the prison.
Originality/value
This study demonstrated important and modifiable factors associated with prisoners’ depression. It also evaluated the contribution of new variables (such as participation in the duty work, nutritional status and physical activity) that were not considered in previous local studies.
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Saurabh Kumar Yadav, Arvind Kumar Rajput, Nathi Ram and Satish Chandra Sharma
This study aims to analyze the dynamic performance of aerostatic thrust bearing for different geometries of recess. Different geometries of recess of equal recess area, i.e…
Abstract
Purpose
This study aims to analyze the dynamic performance of aerostatic thrust bearing for different geometries of recess. Different geometries of recess of equal recess area, i.e. circular, elliptical, rectangular and annular, have been considered in analysis. The work also analyzes the influence of tilt angle on the performance of thrust bearing. To compute the unknown pressure field, the Reynolds equation governing the flow of compressible lubricant (air) has been solved using finite element formulation. Further, separate finite element formulations have been carried out to compute fluid film stiffness and damping coefficients directly. This method provides quick computation of stiffness and damping coefficients of aerostatic thrust bearing than the usual approach.
Design/methodology/approach
As the Reynolds equation governing the flow of compressible lubricant is nonlinear partial differential equation, the computation of the stiffness and damping coefficient follows an iterative procedure. It requires a lot of computational energy. Therefore, in the present work, a novel technique based on finite element formulation is suggested to compute air film stiffness and damping coefficient in aerostatic thrust bearing.
Findings
A novel technique based on finite element formulation is illustrated to simulate the performance of tilted pad aerostatic thrust bearing. On the basis of simulated results, following key conclusions may be drawn. The static and dynamic performance of a circular aerostatic tilted thrust pad bearing is significantly affected with a change in the value of tilt parameter and the shape of the recess.
Research limitations/implications
Implications are as follows: direct computation of air film damping coefficient is performed without perturbation method in finite element method (FEM); influence of tilt on aerostatic thrust bearing is studied; influence of recess shape on aerostatic thrust bearing is observed; and finite element formulation of aerostatic thrust bearing is performed.
Originality/value
The present work will be quite useful for bearing designer and academicians.
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Devender Sheoran, Komal Yadav, Baljit Singh Punia and Kapil Kumar Kalkal
The purpose of this paper is to analyse the transient effects in a functionally graded photo-thermoelastic (TE) medium with gravity and rotation by considering two generalised TE…
Abstract
Purpose
The purpose of this paper is to analyse the transient effects in a functionally graded photo-thermoelastic (TE) medium with gravity and rotation by considering two generalised TE theories: Lord–Shulman (LS) and Green–Lindsay (GL). The governing equations are derived in rectangular Cartesian coordinates for a two dimensional problem.
Design/methodology/approach
All the physical properties of the semiconductor are supposed to vary exponentially with distance. The analytical solution is procured by employing normal mode technique on the resulting non-dimensional coupled field equations with appropriate boundary conditions.
Findings
For the mechanically loaded thermally insulated surface, normal displacement, stress components, temperature distribution and carrier density are calculated numerically with the help of MATLAB software for a silicon semiconductor and displayed graphically. Some particular cases of interest have also been deduced from the present results.
Originality/value
The effects of rotation and non-homogeneity on the different physical fields are investigated on the basis of analytical and numerical results. Comparisons are made with the results predicted by GL theory in the presence and absence of gravity for different values of time. Comparisons are also made between the three theories in the presence of rotation, gravity and in-homogeneity. Such problems are very important in many dynamical systems.
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