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A quadrilateral linear element for plane stress/plane strain analysis, formulated using a system of bars located at the Gauss integration points, is presented. A special bar element is formulated and the finite element is thereafter considered as an assembly of bars. The formulation presented is used in an attempt to explain the numerical problems arising when considering incompressible materials and reduced integration.

The semi‐loof element is probably one of the most efficient for the solution of thin shells of arbitrary geometry. It was originally published by Irons and since then it has been the object of much research with respect to its philosophy and performance in various structural situations.

According to Figure 1, semi‐loof shell, plate and beam elements are implemented in such a way that three independent blocks are formed to obtain the stiffness, mass, load and stress matrices. These three blocks are controlled by subroutine MSTIF, which is directly called from a standard FE program.

A model for the analysis of plain and reinforced concrete structures is developed in the present work. In the plain concrete the localisation of the microcracking within a small band is formulated in terms of constant fracture energy. In the reinforced concrete the model considers the cracking localisation in the element, according to the expressions of Model Code 1990. The objective of this model is to approximate the tension stiffening effect observed in the reinforced concrete elements submitted to tensile stresses. The reinforcing steel is analysed with an element overlapped to the concrete element, having equivalent nodal displacements. Numerical examples are presented and compared with experimental and other numerical results.

The Semiloof shell element stiffness and mass matrices are analysed. Various integration rules for the stiffness matrix are used, and the influence of these rules on the existence of mechanisms and on the element spectra is studied. Some methods for lumping the mass matrix are attempted with special reference to a method imposing a given behaviour of the spectra of eigenvalues.

Implicit solutions in viscoplastic analysis of structures are very often avoided due to the fact that they lead to non‐symmetric systems of equations. On the other hand, structures such as soils have a marked non‐associate behaviour that has to be taken into consideration. Here the implicit solutions are formulated in a way that, even for non‐associate models, the system of equations is kept as symmetric. Apart from an ‘exact’ formulation of the algorithm other possibilities are considered and tested in the numerical examples given.

Presents the formulation of a new triangular finite element for plate bending. The element has 15 degrees of freedom: six displacements at the corners and midside nodes and nine rotations normal to the element side, three along each element side. The element is based on the Kirchhoff theory for plate bending and the shape functions are derived from a complete quartic polynomial. Presents a numerical assessment of the element, showing that the element passes the patch test and that it possesses a good converge rate. The stiffness matrix is integrated exactly.

The initial stiffness method has been extensively adopted for elasto‐plastic finite element analysis. The main problem associated with the initial stiffness method, however, is its slow convergence, even when it is used in conjunction with acceleration techniques. The Newton‐Raphson method has a rapid convergence rate, but its implementation resorts to non‐symmetric linear solvers, and hence the memory requirement may be high. The purpose of this paper is to develop more advanced solution techniques which may overcome the above problems associated with the initial stiffness method and the Newton‐Raphson method.

In this work, the accelerated symmetric stiffness matrix methods, which cover the accelerated initial stiffness methods as special cases, are proposed for non‐associated plasticity. Within the computational framework for the accelerated symmetric stiffness matrix techniques, some symmetric stiffness matrix candidates are investigated and evaluated.

Numerical results indicate that for the accelerated symmetric stiffness methods, the elasto‐plastic constitutive matrix, which is constructed by mapping the yield surface of the equivalent material to the plastic potential surface, appears to be appealing. Even when combined with the Krylov iterative solver using a loose convergence criterion, they may still provide good nonlinear convergence rates.

Compared to the work by Sloan et al., the novelty of this study is that a symmetric stiffness matrix is proposed to be used in conjunction with acceleration schemes and it is shown to be more appealing; it is assembled from the elasto‐plastic constitutive matrix by mapping the yield surface of the equivalent material to the plastic potential surface. The advantage of combining the proposed accelerated symmetric stiffness techniques with the Krylov subspace iterative methods for large‐scale applications is also emphasized.

Despite the immense amount of literature on ethical leadership and leader‒member exchange (LMX), little is known about how and when ethical leadership and LMX are more/less effective in prompting employee creativity. It is proposed that ethical leadership affects creativity through LMX. Furthermore, the authors draw upon an interactionist perspective and suggest that employee psychological capital is a dispositional boundary condition that influences the effectiveness of LMX in promoting employee creativity. The paper aims to discuss these issues.

Using a survey questionnaire, data were collected from 557 nurses and their supervisors working in public sector hospitals. The data were collected in two phases (time lagged) to avoid common method bias. Moderated mediation analysis was performed, using model 14 of PROCESS, to probe hypothesized relationships.

The results of the moderated mediation suggest that ethical leadership and LMX predict creativity. Ethical leadership indirectly affects creativity through LMX. Employee psychological capital moderates the direct effect of LMX and the indirect effect of ethical leadership on employee creativity.

The study contributes to the extant literature, as the findings suggest that, being a dispositional boundary condition, psychological capital plays a contingent role in explaining LMX and the ethical role of leaders in fostering creativity. Moreover, the results also confirm previous findings, which suggested that ethical leaders promote creativity.

The findings imply that ethical leadership and exchange relationships are important for promoting creativity. Given that creativity is a complex product of an individual’s behavior, high psychological capital employees obtain benefits of quality exchange relationships and utilize them to elicit creativity. Managers are recommended to proactively develop and promote exchange relationships as well as positive psychological resources among employees to achieve creativity.

The study is unique in its scope and contribution, as it tries to develop an understanding of how and when ethical leadership and LMX foster employee creativity. Using an interactionist perspective to theorize psychological capital as a second-stage moderator is, thus, a unique contribution of this study.

The purpose of this paper is to examine the complex relationships between common bond attachment, common identity attachment, self-esteem and virtual community citizenship behavior (VCCB). This study identifies two broad categories of VCCB: citizenship behaviors directed toward benefitting other individuals (VCCBI) and citizenship behaviors directed toward benefitting the virtual community (VCCBC).

The authors apply partial least squares structural equation modeling to test the hypotheses, using a sample of 388 valid responses.

The results indicate that common bond attachment and common identity attachment have a significant effect on self-esteem, which, in turn, has a significant effect on VCCBI and VCCBC. The results also indicate that common bond attachment has a significant effect on VCCBI, and that common identity attachment has a significant effect on VCCBC.

This study contributes to a better understanding of VCCBs through common identity and common-bond theory, social identity theory and the stimulus-organism-response framework.