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In this paper, postbuckling behavior and progressive failure of laminated plates considering geometric nonlinearity and evolving material damage under uniaxial, biaxial compressive and in-plane shear loadings are studied. The damage model is based on a generalized macroscopic continuum theory within the framework of irreversible thermodynamics and enables to predict the progressive damage and failure load. Damage variables are introduced for the phenomenological treatment of degradation of the stiffness properties of laminated plates due to microscopic defects. The analysis is carried out using field-consistent finite element approach based on first-order shear deformation theory. The nonlinear governing equations are solved using the Newton–Raphson iterative technique coupled with the adaptive displacement control method to trace the pre- and postbuckling equilibrium path. The damage evolution equations are solved at every Gauss point using Newton–Raphson iterative technique within each loading/displacement increment iteration. The detailed parametric study is carried out to investigate the influences of evolving damage, span-to-thickness ratio, lamination scheme, boundary conditions and aspect ratio on the postbuckling response and failure load of laminated plates under in-plane loading. The ratio of failure load to buckling load increases with increase in thickness ratio due to the dominating restoring action of in-plane stretching forces in postbuckling region of thin plates whereas the thick plates depict material failure prior to buckling point. Thin plates with SSFF boundary conditions with evolving damage depict softening postbuckling response whereas the plates with other boundary conditions considered depict hardening response. [ABSTRACT FROM PUBLISHER]

This template represents the basic guidelines and desired layout final manuscript of Tooth contact stresses are often calculated with the Hertz formula when the tooth load are known. Since the Hertz formula was deduced from two symmetric elastic cylinders, so it is not precise enough for contact stress calculation of gear teeth, also Hertz formula cannot calculate correct stress values of contact teeth. It is widely agreed that the theoretical analysis (FEM by using ANSYS) of spur gears can be performed using 2D approach (point to point). This paper investigates the characteristics of an Involutes gear system including contact stresses between pair of the gears (surface to surface contact)(2D and 3D) for polyimide materials. To enable the investigation of contact problems with Finite Element Method (FEM), the stiffness relationship between the two contacts areas is usually established through a spring placed between the two contacting areas. The results of the two and three dimensional FEM analyses from ANSYS (surface to surface contact) are presented. These stresses are compared between two and three dimensional. Both results agree very well. This indicates that the (FEM) model (surface to surface contact) is accurate more than (point to point) and (Hertz's equations) results because it is very near to the facts. Also the different of the results between two and three dimension are very small and equal (3.95%). [ABSTRACT FROM AUTHOR]

The present paper employs an analytical solution, based on double Chebyshev series technique for the dynamic buckling of composite laminated rectangular plates under transient in-plane mechanical loading and transverse temperature gradient across the thickness. The formulation is based on first-order shear deformation theory and von-Kármán's nonlinearity. The governing nonlinear coupled partial differential equations of motion are linearized by quadratic extrapolation technique and discretized in space domain and time domain by fast converging Chebyshev polynomials and Houbolt time marching scheme, respectively. The resulting simultaneous linear algebraic equations are solved, iteratively. Buckling and response results are presented for uniaxial and biaxial in-plane mechanical loadings along with transverse temperature gradient across the thickness of symmetric and unsymmetric angle-ply and cross-ply laminated composite rectangular plates with different edge conditions. [ABSTRACT FROM AUTHOR]

The stability of postbuckled equilibrium configurations and the nonlinear dynamic characteristics of cross-ply laminated heated cylindrical shells are investigated employing semi-analytical shell finite element. The presence of asymmetric perturbation in the form of small magnitude load spatially proportional to the linear buckling mode shape is considered to initiate the bifurcation of the shell deformation from axisymmetric mode to asymmetric one. The frequencies of small oscillations about equilibrium configuration are obtained by solving the eigenvalue problem formulated using tangent stiffness matrix of the converged equilibrium configuration and mass matrix. The study reveals that the prediction of the postbuckling equilibrium configuration from nonlinear static analysis depends on the nature (longitudinally symmetric/antisymmetric) of initial disturbance. The longitudinally antisymmetric postbuckled equilibrium configuration is stable whereas the longitudinally symmetric one is unstable. The nonlinear dynamic response shows that the shell with longitudinally symmetric disturbance jumps from symmetric mode to antisymmetric mode and the predicted equilibrium configuration is of antisymmetric nature irrespective of the type of initial disturbance. The nonlinear forced dynamic response of the heated shell in the prebuckling region differs significantly from that in the postbuckling region. [ABSTRACT FROM AUTHOR]

Due to an increase in industrialization and urbanization, massive amounts of solid waste biomass are speedily accumulating in our environment, which poses several adverse effects on habitat and human health thus becoming a matter of discussion in the environmental community. With reference to the circular economy, continuous efforts have been put forward for setting up an organised management approach in combination with an efficient treatment technique for increasing the profitable utilization of solid waste. This review aims to provide a systematic discussion on the recent thermochemical technologies employed for converting waste biomass generated from different sources into valuable products like biochar, bio-oil, heat, energy and syngas. The article further focuses on a few important aspects of thermochemical conversion of waste biomass to useful products like technical factors affecting thermochemical processes, applications of by-products of thermochemical conversion, and biological pretreatment of waste biomass. The review assists interesting recent and scientific trends for boosting up the systematic management and valorization of solid waste through low-cost, efficient, environment-friendly and sustainable technologies., Competing Interests: The authors have no conflicts of interest to declare., (© 2024 The Author(s).)

Increasing competition in healthcare services, it is imperative that physicians and family-care practitioners seek ways to attract and retain patients. Building relationships with existing patients is one sure way to continued patronage and increased clientele. The purpose of this paper is to examine antecedents of rapport and its influence on perceived relationships in the context of patient-physician interaction. Study using cross-sectional survey method with structured questionnaire was used for data collection. Structural Equation Modeling was used for analyzing the data collected from 326 patients residing in Karnataka, India. The finding suggests that respect, responsibility and understanding have significant influence on relational cohesion with rapport acting as mediating variable. The results add to the empirical validity of the relationship among rapport, respect & relationship, as it is required to understand studied in Indian context. The finding provides new directions for both healthcare professionals and institutions in their endeavor of building relationships with their customers (Patients) by emphasizing the need for developing 'rapport' as an integral part of service interaction. Future research like longitudinal and experimental studies can provide more conclusive evidence regarding the influence of service behaviour on rapport., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

Cellulose obtained from plants is a bio-polysaccharide and the most abundant organic polymer on earth that has immense household and industrial applications. Hence, the characterization of cellulose is important for determining its appropriate applications. In this article, we review the characterization of cellulose morphology, surface topography using microscopic techniques including optical microscopy, transmission electron microscopy, scanning electron microscopy, and atomic force microscopy. Other physicochemical characteristics like crystallinity, chemical composition, and thermal properties are studied using techniques including X-ray diffraction, Fourier transform infrared, Raman spectroscopy, nuclear magnetic resonance, differential scanning calorimetry, and thermogravimetric analysis. This review may contribute to the development of using cellulose as a low-cost raw material with anticipated physicochemical properties. HIGHLIGHTS: Morphology and surface topography of cellulose structure is characterized using microscopy techniques including optical microscopy, transmission electron microscopy, scanning electron microscopy, and atomic force microscopy. Analytical techniques used for physicochemical characterization of cellulose include X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, nuclear magnetic resonance spectroscopy, differential scanning calorimetry, and thermogravimetric analysis., (© 2022 Wiley Periodicals LLC.)