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This paper aims to propose a macro modeling approach to simulate the mechanical behavior and the failure of spot welded joints in structural crashworthiness computations.

A connector element is proposed to simulate the behavior and failure of spot weld joints. An elastic-plastic damageable model is used to describe the non-linear response and rupture. The connector model involves several parameters that have to be defined. Some are directly identified based on mechanical interpretations and experimental tests characteristics. The remaining parameters are identified through a finite element model updating approach using Arcan tests. Resulting from a sensitivity analysis, an original two steps optimization methodology, using the Modes I and II Arcan tests results sequentially, has been implemented to identify the remaining model parameters.

The numerical results for Arcan tests in mixed Modes I/II are in a good agreement with the experimental ones. The model is also validated on tensile pull-out, single lap shear and coach-peel tests.

By comparison with previous published results, the proposed model brings a significant improvement. The main innovative aspects of this work are as follows: the proposed formulation, a reduced number of parameters to optimize, an original sequential optimization methodology based on physical and mechanical analyses and a mesh size independent connector element.

The purpose of this paper is the development and the assessment of detailed and macro-modelling methodology approaches, suitable for the analysis of composite material bolted joints.

A benchmark single-lap, single-bolt composite joint configuration is investigated, in order to demonstrate the different joint analysis approaches which are applicable in advanced riveted/bolted parts of aeronautical structures. In particular, several joint macro-models, i.e. numerical and analytical ones, as well as a detailed three-dimensional FE solid joint representation, were developed and compared in terms of stiffness prediction, while they were validated using respective experimental results. In addition, the numerical macro-model is implemented in a full scale, multi-bolt fuselage panel in order to demonstrate its capability to efficiently predict the panel’s response under compressive loads.

Good correlation was observed between the majority of the models’ predictions and the relative experimental data regarding the lap joint configuration, while the simplified numerical macro-model showed some discrepancies due to the contact instabilities, which, however, may be accepted taking into account the remarkable solution time reductions. In the same manner, the FE macro-model illustrates sufficient accuracy in the prediction of the panel’s response, while, simultaneously, it maintains a low CPU time.

The present study is part of Nikolaos Perogamvros’ doctoral thesis, an original research work. There are very limited literature papers which include the development and the assessment of different efficient and detailed composite joint analysis approaches, regarding their accuracy and efficiency in the stiffness prediction of a composite bolted joint configuration, as well as on the prediction of a multi-bolt panel’s response.

The research aims to establish the predictors of the acceptance of technical and organizational measures for the protection of personal data to ensure information privacy in Croatian libraries, starting from the constructs of the APCO Macro Model.

Two data collection methods were used: the online survey questionnaire method and the analysis of the websites of independent libraries in the Republic of Croatia.

The results show that the acceptance of measures for personal data protection by a library manager is mostly influenced by perceived knowledge, while culture and trust have a positive correlation of moderate strength. Awareness has a low positive correlation, and privacy experience is not statistically related to the acceptance of measures. There is no statistically significant difference in the acceptance of measures for the protection of personal data concerning age and work experience in the profession. There is a statistically significant correlation between compliance with the principle of transparency and the size of the library.

The study is valuable as it examined the characteristics of the culture of information privacy in libraries and determined the existence and impact of factors that influence ensuring the information privacy of users in Croatian libraries.

This study aims to posit that managerial value would be one of the responsible factors for the difference in corporate social responsibility practice among businesses. It then empirically tested the effect of managerial value, with the moderation of organizational culture, on corporate social responsibility practice.

The authors have devised a “moderated micro-macro model” type of multilevel model, wherein managerial value took the micro (individual level) predictor variable role, stakeholder-based corporate social responsibility practice the macro (organizational level) outcome variable role and organizational culture the macro level moderating variable role. Because they need the attention of inquiry, large manufacturing firms in the Amhara region of Ethiopia, with a sample size of 53, constituted the organizational level units. The recent performance of the firms against corporate social responsibility practice and organizational culture have been judged by 473 randomly chosen employees. Managerial value has been rated by randomly picked managers, numbered 253. Analytically, Croon and van Veldhoven’s multilevel analytical package and Mplus software suited the designed model.

The study has revealed that managerial value, indeed, is a potential positive driver of CSR practice, the two managerial value dimensions demonstrated differential effects on corporate social responsibility practice and only one of the organizational culture dimensions, hierarchical culture, played a moderation role in managerial value – corporate social responsibility practice link.

The model and this empirical test have not been previously verified.

Proposes a methodology for dealing with the problem of designing a material microstructure the best suitable for a given goal.

The chosen model problem for the design is a two‐phase material, with one phase related to plasticity and another to damage. The design problem is set in terms of shape optimization of the interface between two phases. The solution procedure proposed herein is compatible with the multi‐scale interpretation of the inelastic mechanisms characterizing the chosen two‐phase material and it is thus capable of providing the optimal form of the material microstructure. The original approach based upon a simultaneous/sequential solution procedure for the coupled mechanics‐optimization problem is proposed.

Several numerical examples show a very satisfying performance of the proposed methodology. The latter can easily be adapted to other choices of design variables.

Confirms that one can thus achieve the optimal design of the nonlinear behavior of a given two‐phase material with respect to the goal specified by a cost function, by computing the optimal form of the shape interface between the phases.

A method peculiar to sociocybernetics as a paradigm is dynamic simulation. In the case of information technological (IT) systems, which are socio‐technical systems, a qualitative (conceptual, cognitive) approach is more appropriate than a quantitative one. Already intermediate results of conceptual work aimed at a computer model have been found useful. Illustrates this via three case studies from IT in health care, in which the sociocybernetic problem‐functionalist conceptual (SPC) modelling technique was used. Two studies are from the “EUROCARDS Concerted Action on Extending the Use of Patient Data Cards”; the third concerns the development of health information systems in the Aral Basin. In all cases, a wide variety of information and materials was needed for modelling. To keep track of this, proposes a sociocybernetic standard variable number (SC‐SVN).

Distribution concerns who gets what. But does “who” refer to the personal distribution of income among individuals or the functional distribution of income among suppliers of productive factors? For nearly 150 years, Anglophone distribution theory followed the Ricardian emphasis on functional distribution – the income shares of labor, land, and capital. Only beginning in the 1960s, and consolidated by a research outpouring in the early 1970s, does mainstream economics turn to the personal conception of distribution. This essay documents Anglophone (primarily American) economics’ move from functional to personal distribution, and tries to illuminate something of its causes and timing.

A large number of earthquake damages showed that infill walls have obvious influence on the seismic damage performance of RC frame structures. The purpose of this paper is to study the effect of infill walls on the cumulative plastic deformation energy of RC frame structures, for which four RC frame structures are build and the time-history response analysis under unidirectional seismic action is presented.

The time-history response analysis under unidirectional seismic action is presented. Then the effect of periodic reduction coefficient on the cumulative plastic deformation energy of the structures, the beams and the columns is investigated.

Finally, the quantitative calculation formulas are provided. The results show that the periodic reduction coefficient has an obvious effect on the distribution of the accumulated plastic deformation energy, and the influence rules are presented here.

The effect of infill walls on the cumulative plastic deformation energy of RC frame structures is quantitatively analyzed here.

The purpose of this study is to develop a homogenization approach that ensures both high accuracy and time-efficient solution for elastic-plastic functionally graded composites.

The paper presents a novel two-stage hybrid homogenization approach that combines advantages of the mean field homogenization and homogenization based on the finite element method (FEM). The groundbreaking nature of the developed approach is associated with division of the hybrid homogenization procedure into two stages, which allows to very efficiently determine the solution for arbitrary volume fraction of the reinforcement. This paper concerns also on modelling of composites with randomly distributed prolate and oblate particles. For this purpose, the hybrid homogenization was implemented in the framework of the discrete orientation averaging procedure involving pseudo-grain discretization method.

Agreement between the results obtained using the proposed approach and the standard FEM-based homogenization is very good (up to the volume fraction of 0.3).

The proposed two-stage homogenization approach allows to obtain the solution for materials with arbitrary volume fraction of the reinforcement very efficiently; therefore, it is highly beneficial for the two-scale modeling of nonlinear functionally graded materials and structures.

The purpose of this paper is to determine the representative volume element (RVE) size for quasi‐brittle materials using a discrete approach, namely a lattice‐particle model.

Different material samples are generated and subjected to study regarding its size, maximum aggregate size and boundary conditions. In order to determine the mechanical properties such as the elastic modulus, Poisson's ratio or tensile strength, several tension tests are carried out. For this purpose, a lattice‐particle approach is used to model concrete's fracturing behavior. The information provided by the previous simulations is implemented in a statistical analysis to determine the size of the RVE.

The determination of the RVE size for quasi‐brittle materials is successfully achieved by means of a lattice‐particle model. Computed results show a good agreement with other results reported in the bibliography.

Within a general multiscale framework, the determination of the RVE size is of great interest and some studies have been performed for random heterogeneous materials. However, these analyses are mainly continuum‐based. The estimation of the RVE size is important for correctly predicting the mechanical properties and can be used in different multiscale schemes.