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This paper aims to study the mechanism of hydrogen embrittlement in 12Cr2Mo1R(H) steel, which will help to provide valuable information for the subsequent hydrogen embrittlement research of this kind of steel, so as to optimize the processing technology and take more appropriate measures to prevent hydrogen damage.

The hydrogen diffusion coefficient of 12Cr2Mo1R(H) steel was measured by the hydrogen permeation technique of double electrolytic cells. Moreover, the influence of hydrogen traps in the material and experimental temperature on hydrogen diffusion behavior was discussed. The first-principles calculations based on density functional theory were used to study the occupancy of H atoms in the bcc-Fe cell, the diffusion path and the interaction with vacancy defects.

The results revealed that the logarithm of the hydrogen diffusion coefficient of the material has a linear relationship with the reciprocal of temperature and the activation energy of hydrogen atom diffusion in 12Cr2Mo1R(H) steel is 23.47 kJ/mol. H atoms stably exist in the nearly octahedral interstices in the crystal cell with vacancies. In addition, the solution of Cr/Mo alloy atom does not change the lowest energy path of H atom, but increases the diffusion activation energy of hydrogen atom, thus hindering the diffusion of hydrogen atom. Cr/Mo and vacancy have a synergistic effect on inhibiting the diffusion of H atoms in α-Fe.

This article combines experiments with first-principles calculations to explore the diffusion behavior of hydrogen in 12Cr2Mo1R(H) steel from the macroscopic and microscopic perspectives, which will help to establish a calculation model with complex defects in the future.

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.

The purpose of this paper is to design and develop 14-degree of freedom (DOF) robotic micromanipulator with which LIGA devices and axle hole part can be both manipulated and assembled.

The in-house robotic microassembly system is composed of a 6-DOF large motion serial robot with microgrippers, a hexapod six-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-part figures can be acquired simultaneously by the microscope with 1.67 to 9.26 micron optical resolution. The relative discrepancy between the two parts can be calculated from image plane coordinate instead of calculating the space transformation matrix. A modified microgripper was designed to clamp meso-scale parts and its effectiveness was confirmed experimentally. Through the use of the other vision system, the insert action can be successfully manipulated. A laser ranger finder was integrated in this micro-assembly system to measure the assembly result.

A new 14-DOF robotic micromanipulator, including eight axes automatically and six axes manually, has been developed for the assembly of LIGA meso-scale flat parts and axle hole parts. The microassembly system with coaxial alignment function (MSCA) system is able to concurrently manipulate all eight axes automatically and six axes manually.

The robotic microassembly is applied in the assembly of meso-scale parts. The new capabilities of the MSCA will allow for the assembly of microsystems more efficiently and more precisely.

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.

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 investigate the irrevocable role of cause-related marketing (CRM) and its research imperative, exploring its contemporary insights in and across international markets, toward scholarly and executive application.

This research is theoretical and it compiles and interrelates, in a multiperspective fashion, significant extant works in the field; focusing on how established and emergent variables and constructs can be leveraged, in order to develop insights into what does and does not work in international CRM.

Extant works on international CRM still present significant gaps pertaining to key questions. Furthermore, true understanding of CRM stems from comprehending consumers, both individually and collectively; and both their underlying and contextual motivators, factors and forces. This calls for a multiperspective and cross-disciplinary approach to CRM to that weaves in contextual (sociocultural, etc.) elements to the equation.

Limitations naturally pertain to the research's theoretical nature that requires empirical testing.

CRM offers consumers both the means and the ends of acquiring their target core value benefits, additionally or peripherally to their core purchase purpose; potentially making the difference between business/brand success and failure.

Through CRM, the contemporary consumer seeks product value benefits that transcend quality and functionality (etc.), to engulf abstract and intangible values pertaining to social, ethical, self-image and self-actualization factors.

The comprehensive review, contextual elucidations and cross-disciplinary perspectives of this paper originally present the scope, depth, complexity and gaps of the subject, and pave the way for the research that still needs to ensue.

The purpose of this paper is to design a microgripper that can achieve nondestructive gripping of a miniaturized ultra-thin-walled cylindrical part.

The microgripper is mainly made of an inflatable silica gel gasbag, which can minimize the damage to the part in the gripping process. This paper introduces the design principle of a flexible air-filled microgripper, which is applied in an in-house microassembly system with coaxial alignment function. Its parameters and performance specifications have been obtained by simulation, experiment demarcating. The results show that the microgripper is able to grasp an ultra-thin-walled part non-destructively.

For the microgripper, finite element simulations and experiments were carried out, and both results indicate that the microgripper can achieve nondestructive gripping of a miniaturized ultra-thin-walled cylindrical part, with good stability, great grasping force and high repeat positioning accuracy.

Gripping the ultra-thin-walled part may lead to deformation and destruction easily. It has been a big bottleneck hindering successful assembly. This article introduces a novel microgripper using an inflatable sac. The work is interesting from an industrial point of view for a specific category of assembly applications. It provides a theoretical guidance and technical support to design a microgripper for a miniaturized ultra-thin-walled part of different sizes.