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The purpose of this paper is to investigate on the behaviour of a delaminated stiffened panel; the delamination growth is simulated via fracture elements implemented in B2000++® code based on the Modified Virtual Crack Closure Technique (MVCCT), matrix cracking and fibre failure have been also taken into account.

In order to correctly apply the MVCCT on the delamination front a very fine three-dimensional (3D) mesh is required very close to the delaminated area, while a 2D-shell model has been employed for the areas of minor interest. In order to couple the shell domain to the solid one, shell-to-solid coupling elements based on kinematic constraints have been used.

Results obtained with the global/local approach are in good correlation with those obtained with experimental results.

The global/local approach based on kinematic coupling elements in conjunction with fracture elements allows to investigate and predict the behaviour of a stiffened delaminated composite panel in an efficient and effective way.

The purpose of this paper is to investigate and to assess the capabilities of the most common finite element (FE)‐based tools to deal with global‐local analysis. Two kinds of coupling were investigated: shell to shell and shell to solid.

The issue of connecting non‐matching FE global and local models, characterized by different mesh refinements and/or different element types, was addressed by introducing appropriate kinematic constraints on the nodes at the interfaces. The coupling techniques available in the three FE‐based codes (ABAQUS^®, NASTRAN^® and ANSYS^®), were assessed by applying them on a common numerical test case (non‐linear buckling analysis of a square plate). Results of the global‐local simulations were compared to the results obtained for relevant reference solutions.

The continuity of displacements and stresses across the interface between global and local models and the influence of the presence of the local model on the global model solution were used as parameters to test the quality of the results. It was observed that the tools implemented in the different codes provide different results. The results characterized by a higher quality were found by using the Multi Point Constraint available in ABAQUS^®.

When dealing with complex structures, multi‐scale (global‐local) approaches are commonly adopted to optimize the computational cost by increasing mesh refinements and/or introducing elements with different formulations in specific region of the structures identified as “local model”. In this paper an overview of the coupling tools available in the main commercial FE code is given.

Nowadays, artificial intelligence (AI) technology has demonstrated extensive applications in the field of art design. Attribute editing is an important means to realize clothing style and color design via computer language, which aims to edit and control the garment image based on the specified target attributes while preserving other details from the original image. The current image attribute editing model often generates images containing missing or redundant attributes. To address the problem, this paper aims for a novel design method utilizing the Fashion-attribute generative adversarial network (AttGAN) model was proposed for image attribute editing specifically tailored to women’s blouses.

The proposed design method primarily focuses on optimizing the feature extraction network and loss function. To enhance the feature extraction capability of the model, an increase in the number of layers in the feature extraction network was implemented, and the structure similarity index measure (SSIM) loss function was employed to ensure the independent attributes of the original image were consistent. The characteristic-preserving virtual try-on network (CP_VTON) dataset was used for train-ing to enable the editing of sleeve length and color specifically for women’s blouse.

The experimental results demonstrate that the optimization model’s generated outputs have significantly reduced problems related to missing attributes or visual redundancy. Through a comparative analysis of the numerical changes in the SSIM and peak signal-to-noise ratio (PSNR) before and after the model refinement, it was observed that the improved SSIM increased substantially by 27.4%, and the PSNR increased by 2.8%, serving as empirical evidence of the effectiveness of incorporating the SSIM loss function.

The proposed algorithm provides a promising tool for precise image editing of women’s blouses based on the GAN. This introduces a new approach to eliminate semantic expression errors in image editing, thereby contributing to the development of AI in clothing design.

The purpose of this paper is to consider divergence of composite plate wings as well as slender wings with thin-walled cross-section of small-size airplanes. The main attention is paid to establishing of closed-form mathematical solutions for models of wings with coupling effects. Simplified solutions for calculating the divergence speed of wings with different geometry are established.

The wings are modeled as anisotropic plate elements and thin-walled beams with closed cross-section. Two-dimensional plate-like models are applied to analysis and design problems for wings of large aspect ratio.

At first, the equations of elastic deformation for anisotropic slender, plate-like wing with the large aspect ratio are studied. The principal consideration is delivered to the coupled torsion-bending effects. The influence of anisotropic tailoring on the critical divergence speed of the wing is examined in closed form. At second, the method is extended to study the behavior of the large aspect ratio, anisotropic wing with box-like wings. The static equations of the wing with box-like profile are derived using the theory of anisotropic thin-walled beams with closed cross-section. The solutions for forward-swept wing with box-like profiles are given in analytical formulas. The formulas for critical divergence speed demonstrate the dependency upon cross-sectional shape characteristics and anisotropic properties of the wing.

The following simplifications are used: the simplified aerodynamic theory for the wings of large aspect ratio was applied; the static aeroelastic instability is considered (divergence); according to standard component methodology, only the component of wing was modeled, but not the whole aircraft; the simplified theories (plate-lime model for flat section or thin-walled beam of closed-section) were applied; and a single parameter that defines the rotation of a stack of single layers over the face of the wing.

The simple, closed-form formulas for an estimation of critical static divergence are derived. The formulas are intended for use in designing of sport aircraft, gliders and small unmanned aircraft (drones). No complex analysis of airflow and advanced structural and aerodynamic models is necessary. The expression for chord length over the span of the wing allows for accounting a board class of wing shapes.

The derived theory facilitates the use of composite materials for popular small-size aircraft, and particularly, for drones and gliders.

The closed-form solutions for thin-walled beams in steady gas flow are delivered in closed form. The explicit formulas for slender wings with variable chord and stiffness along the wing span are derived.

The main objective of this work is to assess the current capabilities of different commercial finite element (FE) codes in simulating the progressive damage of composite structures under quasi-static loading condition in post-buckling regime.

Progressive failure analysis (PFA) methodologies, available in the investigated FE codes, were applied to a simple test case extracted from literature consisting in a holed composite plate loaded in compression.

Results of the simulations are significantly affected by the characteristic parameters needed to feed the degradation models implemented in each code. Such parameters, which often do not have a physical meaning, have to be necessarily set upon fitting activity with an experimental database at coupon level. Concerning the test case, all the codes were found able to capture the buckling load and the failure load with a good accuracy.

This paper would to give an insight into the PFA capabilities of different FE codes, providing the guidelines for setting the degradation model parameters which are of major interest.

The purpose of this paper is to systematically review online ethnography and its boundary challenges. The paper especially focusses on how researchers draw space boundaries, set time boundaries and engage their online field.

The authors perform a systematic review of extant literature and identify 59 papers in 40 different journals as online ethnographies from various management disciplines. The authors perform both qualitative and quantitative analyses on papers in the sample.

The paper identifies how online ethnographers both define boundaries and engage their online field. The paper shows that some of the advantages of online ethnography actually prompt researchers to favor-specific research designs over others.

The authors only focussed on articles adopting online ethnography in organization and management studies that are listed in Social Sciences Citation Index database. Online ethnographies in other research fields and indexes are not studied in this paper.

The paper makes suggestions on how to complement existing online ethnographies to reach a more comprehensive practice of online ethnography.

The systematic review may help researchers to locate useful online ethnography examples across various management disciplines and may contribute to the maturation of online ethnography.

The paper synthesizes emerging trends in online ethnography and identifies how specific advantages actually prompt online ethnographers to limit themselves in their research designs.

The purpose of this research paper is to address the main research gap related to the lack of sufficient information regarding the role of information and communication technologies (ICTs) in second Arab Spring wave in comparison to the first one. The authors analysed the role of ICTs via data regarding the access to ICTs and its influence on organization and spread of the anti-regime protests, i.e. regime change.

Crisis situations are unpredictable, complex and unexpected. The consequences produced by the crisis situations or events may be negative for an individual, community, organization or society as a whole. In the new millennium, ICTs have an important role in deep social crises. The new technologies enable not only the rapid spread of certain political ideas, spin information, but also the spread of misinformation. The control over ICTs in the crisis situations is crucial. The aim of this paper is to indicate effect of the use of ICTs in the crisis situations, i.e. political upheavals in 11 countries of the “Arab Spring”. The contribution of this paper is based on the development of a special theoretical model of analysis that represents the combination of the theoretical considerations in the field of ICTs, as well as the analysis in the field of transitology, i.e. democratization. The first part of the paper is focussed on the development of ICT transition theory of ICTs’ impact on the process of political change, setting the hypotheses and the explanation of methodological approach of the paper. The second part is related to the review and description of data regarding ICTs use, while the third one discusses the impact of the use of ICTs in organizing and spreading protests in the Arab world, in line with the defined theoretical framework. Finally, there are given the research results in terms of confirming or refuting the hypotheses through the analysis of Arab transition cases.

The authors confirmed the main hypothesis of the paper that the factors that determined the role of ICTs in first Spring, also, have determined the role of ICTs in second Spring wave. These factors include high access to ICT tools, weak regime's control over ICTs’ use and important cross-border networking with regional and international audience. All that formed the promotional role of ICTs in regime change in 8 of the 11 countries mentioned in the paper.

Apart from the developed special theoretical model and the analysis of new wave Arab Spring cases, the significance and originality of this paper is reflected in a comprehensive and multidisciplinary approach that connects political changes and the use of ICTs in disseminating certain policies and ideas.

The purpose of this paper is to investigate how perceived leadership effectiveness is related to staff members’ attitudes towards development of elderly care organizations in private and public institutions.

A cross-sectional quantitative survey was conducted using self-report questionnaire that contained Modified Leadership Effectiveness Questionnaire (Heck et al., 2000), the scale of attitude towards change from Preziosi’s Organizational Diagnosis Model (1980) and organizational development intentions measure developed for the study. The respondents were 510 Lithuanian social workers and other staff members employed in different public and private elderly care organizations.

The results revealed that perceived higher leadership effectiveness was associated with more positive employees’ judgements on organization’s readiness to change both in private and public sector elderly care organizations. But perceived leadership effectiveness was not associated with staff members’ intentions to change. Also it was found that different models for private and public sector that explained the importance of particular leadership behaviours in the prediction of employees’ judgements on organizational change and intentions to change were valid.

This study may add to further broaden knowledge on attitudes of staff members towards development of elderly care organization and the role of leadership effectiveness taking into account the type of organization.

The purpose of this paper is to investigate the collaboration between researchers and practitioners on developing standards and guidelines for Facilities Management (FM).

This paper is based on a longitudinal case study on research on FM value adding and its impact on FM standardization and development of a FM Value Guide. The sources used are literature and documents on FM value adding and standardization, published and planned FM standards, the FM Value Guide, internal documents and participant observations and experiences. All authors of this paper have both research and practical background. Two of them have been – and one still is – actively involved in developing European and international FM standards, and all three have been involved in developing the FM Value Guide. The research methodology can be characterized as retrospective action research.

The literature review shows that even though there are many references to standards in research papers, particularly in relation to definitions of concepts, there are only few studies on how research influences standardization and how researchers collaborate with practitioners on developing standards and guidelines. This paper presents a case study showing how research can contribute to standardization and development of guidelines in collaboration with practitioners and makes suggestions on how such collaboration can be improved.

The results of this paper provide understanding and inspiration for how researchers and practitioners can collaborate in the development of standards and guidelines.

To the best of the authors’ knowledge, this paper is the first study on collaboration between researchers and practitioners on developing FM standards and guidelines.