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Poor bending response is a major shortcoming of lower-order elements due to excessive representation of shear stress/strain field. Advanced finite element (FE) formulations for classical elasticity enhance the bending response by either nullifying or filtering some of the symmetric shear stress/strain modes. Nevertheless, the stress/strain field in Cosserat elasticity is asymmetric; consequently any attempt to nullify or filter the anti-symmetric shear stress/strain modes may lead to failure in the constant couple-stress patch test where the anti-symmetric shear stress/strain field is linear. This paper aims at enhancing the bending response of lower-order elements for Cosserat elasticity problems.

A four-node quadrilateral and an eight-node hexahedron are formulated by hybrid-stress approach. The symmetric stress is assumed as those of Pian and Sumihara and Pian and Tong. The anti-symmetric stress components are first assumed to be completely linear in order to pass the constant couple-stress patch test. The linear modes are then constrained with respect to the prescribed body-couple via the equilibrium conditions.

Numerical tests show that the hybrid elements can strictly pass the constant couple-stress patch test and are markedly more accurate than the conventional elements as well as the incompatible elements for bending problems in Cosserat elasticity.

This paper proposes a hybrid FE formulation to improve the bending response of four-node quadrilateral and eight-node hexahedral elements for Cosserat elasticity problems without compromising the constant couple-stress patch test.

This study aims to offer insights regarding the impact of emotional conflict on innovation behavior. This study also explores the boundary conditions by examining the moderating effects of leader-member exchange (LMX) and team-member exchange (TMX) on the relationship between emotional conflict and innovation behavior.

This study used a questionnaire survey to collect data in China. Hypotheses were tested using hierarchical regression analysis. To test for inverted U-shaped relationship between emotional conflict and innovation behavior, the authors computed the squared term for emotional conflict. To investigate moderating roles of LMX and TMX, the authors carried out an interaction term between the main effect variables (emotional conflict and emotional conflict²) and the moderating variables (LMX and TMX).

The empirical findings indicated that emotional conflict had an inverted U-shaped relationship with innovation behavior. Furthermore, LMX and TMX moderated the inverted U-shaped relationship between the emotional conflict and innovation behavior in such a way that the inverted U-shaped relationship was flatter in high-quality LMX and TMX than in low-quality LMX and TMX. That is to say, LMX and TMX may dampen the positive effects of lower levels of emotional conflict on innovation behavior; yet, it may also weaken the negative effects of higher levels of emotional conflict on innovation behavior.

This research can be extended in several ways. First, future research can investigate the impact mechanism of emotional conflict on innovation behavior. Second, future research can analyze other types of moderators at different levels. The last but not the least, future research can test the results using heterogeneous samples. Despite these potential limitations, this study provides an elaborate understanding of the conflict–creativity relationship by outlining the inverted U-shaped relationship between emotional conflict and innovation behavior under the LMX and TMX contexts, which can make important contributions to the conflict management literature.

The findings of this study offer some guidance on how to stimulate innovation behavior through emotional conflict. It suggests that managers should maintain the emotional conflict at the moderate level. Furthermore, managers can strengthen the LMX and TMX to avoid the negative effects of high levels of emotional conflict, and several practices are provided as well.

This study develops an exhaustive understanding of the conflict–creativity relationship by figuring the curvilinear relationship between emotional conflict and innovation behavior, which is the response to the call of Posthuma to focus on the outcomes of conflict management. The findings further provide an empirical evidence of the conceptual argument that the consequences of conflict depend on the situational context by pointing out the important contingency factors of LMX and TMX.

The purpose of this paper is to propose a sub-pixel calibration method for a microassembly system with coaxial alignment function (MSCA) because traditional sub-pixel calibration approaches cannot be used in this system.

The in-house microassembly system comprises a six degrees of freedom (6-DOF) large motion serial robot with microgrippers, a hexapod 6-DOF precision alignment worktable and a vision system whose optical axis of the microscope is parallel with the horizontal plane. A prism with special coating is fixed in front of the objective lens; thus, two parts’ Figures, namely the images of target and base part, can be acquired simultaneously. The relative discrepancy between the two parts can be calculated from image plane coordinate instead of calculating space transformation matrix. Therefore, the traditional calibration method cannot be applied in this microassembly system. An improved calibration method including the check corner detection solves the distortion coefficient conversely. This new way can detect the corner at sub-pixel accuracy. The experiment proves that the assembly accuracy of the coaxial microassembly system which has been calibrated by the new method can reach micrometer level.

The calibration results indicate that solving the distortion conversely could improve the assembly accuracy of MSCA.

The paper provides certain calibration methodological guidelines for devices with 2 dimensions or 2.5 dimensions, such as microelectromechanical systems devices, using MSCA.

Ant colony algorithm is widely used in recent years as a heuristic algorithm. It provides a new way to solve complicated combinatorial optimization problems. Having been enlightened by the behavior of ant colony's searching for food, positive feedback construction and distributed computing combined with certain heuristics are adopted in the algorithm, which makes it easier to find better solution. This paper introduces a series of ant colony algorithm and its improved algorithm of the basic principle, and discusses the ant colony algorithm application situation. Finally, several problems existing in the research and the development prospect of ACO are reviewed.

The purpose of this paper is to examine the joint congruence effect of leadership styles and organizational culture on project members’ innovative behaviors in the construction projects setting.

The proposed hypotheses are tested using polynomial regression with a sample of 217 project managers and employees of different construction projects in China, and plotted through response surface analysis.

The results of polynomial regressions support the congruence effect hypothesis, indicating that more innovative behaviors of the project members could be elicited by a high level of congruence between transformational or transactional leadership styles and organizational culture. Furthermore, asymmetrical incongruence effects are found wherein project members with lower levels of innovative behaviors when project organizational culture is stronger as compared with when two leadership styles are at higher levels. Specifically, the condition is found under the innovation dimension of organization culture, but higher level of innovative behavior conversely displays when the harmony culture is weaker than two leadership styles.

The conceptual model and hypotheses are examined by analyzing cross-sectional and self-reported data collected in China. The findings could be further examined through multi-source or longitudinal, more systematic research.

The findings highlight the pivotal role played by the value congruence of leaders-organizations in motivating employees to be innovative in project organizations. This paper provides knowledge for project managers to help them understand whether and how project members’ innovative behaviors are better motivated by the fit or misfit between the styles of leadership and project organizational cultures. Besides, this study provides the approach or direction for the project leaders training.

This study is one of the first to examine the joint effects of leadership styles and organizational culture on innovative behavior based on the person-organization fit theory and from the perspective of value congruence.

The purpose of this paper is to analyze the sensitivity of the motion error parameters in microassembly process, thereby improving the assembly accuracy. The motion errors of the precision motion stages directly affect the final assembly quality after the machine visual alignment.

This paper presents the error parameters of the in-house microassembly system with coaxial alignment function, builds the error transfer model by the multi-body system theory, analyzes the error sensitivity on the sensitive direction using the Sobol method, which was based on variance, and then gets the ones which made a great degree of influence. Before the sensitivity analyzing, parts of the error sources have been measured to obtain their distribution ranges.

The results of the sensitivity analysis by the Sobol method, which was based on variance, are coincident with the theoretical analysis. Besides, the results provide a reference for the error compensation in control process, for the selection of the precision motion stages and for the installation index of the motion stages of the assembly system with coaxial alignment.

This kind of error sensitivity analysis method is of great significance for improving the assembly accuracy after visual system positioning, and increasing efficiency from the initial motion stage selection to final error compensation for designers. It is suitable for general precision motion systems be of multi-degree of freedom, for the method of modeling, measuring and analyzing used in this paper are all universal and applicative.