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This paper shows a generalization of the classic isotropic plasticity theory to be applied to orthotropic or anisotropic materials. This approach assumes the existence of a real anisotropic space, and other fictitious isotropic space where a mapped fictitious problem is solved. Both spaces are related by means of a linear transformation using a fourth order transformation tensor that contains all the information concerning the real anisotropic material. The paper describes the basis of the spaces transformation proposed and the expressions of the resulting secant and tangent constitutive equations. Also details of the numerical integration of the constitutive equation are provided. Examples of application showing the good performance of the model for analysis of orthotropic materials and fibre‐reinforced composites are given.

The purpose of this paper is to present a new constrained optimization algorithm based on a particle swarm optimization (PSO) algorithm approach.

This paper introduces a hybrid approach based on a modified ring neighborhood with two new perturbation operators designed to keep diversity. A constraint handling technique based on feasibility and sum of constraints violation is adopted. Also, a special technique to handle equality constraints is proposed.

The paper shows that it is possible to improve PSO and keeping the advantages of its social interaction through a simple idea: perturbing the PSO memory.

The proposed algorithm shows a competitive performance against the state‐of‐the‐art constrained optimization algorithms.

The proposed algorithm can be used to solve single objective problems with linear or non‐linear functions, and subject to both equality and inequality constraints which can be linear and non‐linear. In this paper, it is applied to various engineering design problems, and for the solution of state‐of‐the‐art benchmark problems.

A new neighborhood structure for PSO algorithm is presented. Two perturbation operators to improve PSO algorithm are proposed. A special technique to handle equality constraints is proposed.

The purpose of this paper is to present an alternative solution for press-fit technology processes, which could improve the precision of the positioning movements and the stiffness of the structural elements.

A concept is presented and the related kinematics is described. Then, preliminary embodiment evaluations have been performed in terms of kinematics, force control and load distribution on the main structural elements.

Thanks to the additional leg, the proposed solution allows a preload that is capable of compensating the backlash of joints. The particular structure with four extendible legs and eight cardan joints ensures the parallelism between the ground and the plate holding the end effector, without any need of additional controls. However, it implies that the legs are not subjected to pure tension–compression stresses.

This work is focused on the conceptual phase of the design process, with only preliminary embodiment analysis that paves the way for subsequent and more detailed design steps. Especially concerning the actual stiffness of the system, comprehensive evaluations could be performed only after the identification of the particular parts/devices used to implement the main functional elements.

To the best of the authors’ knowledge, this is the first research work that comprehensively describes and analyzes the considered kinematics, within a real industrial application context.

A consistent formulation for unilateral contact problems including frictional work hardening or softening is proposed. The approach is based on an augmented Lagrangian approach coupled to an implicit quasi‐static Finite Element Method. Analogous to classical work hardening theory in elasto‐plasticity, the frictional work is chosen as the internal variable for formulating the evolution of the friction convex. In order to facilitate the implementation of a wide range of phenomenological models, the friction coefficient is defined in a parametrised form in terms of Bernstein polynomials. Numerical simulation of a 3D deep‐drawing operation demonstrates the performance of the methods for predicting frictional contact phenomena in the case of large sliding paths including high curvatures.

A bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view is given. The bibliography at the end of the paper contains 1,726 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1996‐1999.

Group criticism plays an important role in intergroup relations and conflicts, but few studies have related group criticism to intercultural communication contexts. This study aims to explore two cultural groups’ (Chinese international students in the USA and American domestic students) collective face concern as a unique experience in intercultural communication and other psychological responses while encountering group criticism targeting their country image.

A laboratory experiment was conducted assessing Chinese international students (n = 115) and American domestic students’ (n = 100) responses to a research-confederate critic (whose group membership was manipulated) criticizing participants’ country image such as blaming China and the USA for air pollution or using drugs in the Olympics. analysis of covariance, correlational analysis and regression analysis were adopted to analyze the data.

Chinese international students reported higher collective face concerns and lower liking toward the critic compared with American students. When criticism specifically targeted participants’ country image, Chinese international students reported more discomfort feelings than American students; and while responding to the critic who identified as participants’ ingroup member, Chinese international students’ discomfort feelings were more susceptible to their collective face than American students in the same condition.

This study illustrates cultural differences in collective face concerns and psychological reactions in responding to criticism targeting a country image in intercultural communication contexts.

Examines relationships between the role of elementary school principals in teacher in‐service activities and: what principals acquire in administrator in‐service training; and what principals do in regard to teacher follow‐up activities in the classrooms. Using interview and observation techniques, relationships are found which reflect successful efforts extended towards school improvement.

An experimental and numerical study of thermal profiles of 316 L stainless steel during selective laser melting (SLM) was developed. This study aims to present a novel approach to determine the significance and contribution of thermal numerical modeling enhancement factors of SLM.

Surface and volumetric heat models were proposed to compare the laser interaction with the powder bed and substrate, considering the powder size, absorptance and propagation of the laser energy through the effective depth of the metal layer. The approach consists in evaluating the contribution of the thermal conductivity anisotropic enhancement factors to establish the factors that minimized the error of the predicted results vs the experimental data.

The level of confidence of the carried-out analysis is of 97.8% for the width of the melt pool and of 99.8% for the depth of the melt pool. The enhancement factors of the y and z spatial coordinates influence the most in the predicted melt pool geometry.

Nevertheless, the methodology presented in this study is not limited to 316 L stainless steel and can be applied to any metallic material used for SLM processes.

This study is focused on 316 L stainless steel, which is commonly used in SLM and is considered a durable material for high-temperature, high-corrosion and high-stress situations.

The additive manufacturing (AM) technology is a relatively new technology becoming global. The AM technology may have health benefits when compared to the conventional industrial processes, as the workers avoid extended periods of exposure present in conventional manufacturing.

This study presents a novel approach to determine the significance and contribution of thermal numerical modeling enhancement factors of SLM. It was found that the volumetric heat model and anisotropic enhancement thermal approaches used in the present research, had a good agreement with experimental results.

This study explores how marginalized populations in high-hazard-risk areas on the Oregon coast utilize valued locations and social networks to adapt to daily challenges and natural hazards.

We hypothesize that locations most valued for their associated resources (community assets) also support the most social capital. Focus group discussions and a novel conceptual mapping activity were employed to identify preferred community assets and associated social capital for Latinx residents.

Community-based organizations, churches and schools are the preferred community assets found to enable strong social capital, although differences existed in which forms of structural social capital were identified. Mechanisms by which relationships are formed in this case study and implications for disaster resilience are discussed and theoretically linked to other relevant contexts.

We provide policy recommendations to utilize community assets and social capital to support disaster resilience for marginalized populations.

Recruitment of participants through a community-engaged process developed trust with Latinx community members. Focus group design addressed barriers to participation to create space for diverse perspectives. By applying social capital theory to this data, actionable insights are identified to better incorporate the values and needs of marginalized groups into disaster risk reduction efforts.

Particle swarm optimization (PSO) has been applied with success to many numerical and combinatorial optimization problems in recent years. However, a great deal of work remains to be done to improve the particle swarm performance. The purpose of this paper is to present a new adaptive PSO approach to overcome convergence drawbacks. Thus, the updating of the particle position rule and the introduction of new acceleration parameter augment the performance of the proposed model developed in this perspective.

In the studied picture, each particle defined in a multidimensional search space is represented by a vector of three adaptive parameters representing, respectively, the adaptive cognitive factor, the adaptive social factor, and the bi‐acceleration factor. Therefore, to updating its position rule, the authors add a gaussian noise to each updated velocity in order to increase the diversity in the population swarm.

The simulation experiments uses the CEC, 2005 functions benchmark. The achieved results show that the proposed model improves the existing performance of other algorithms compared to the same benchmark.

The proposed algorithm improves the performance of the PSO based on the self‐adaptation strategy. Thus, it can actually resolve hard functions which introduces noisy and shifted functions.