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When handling small-sized shafts and holes, achieving optimal safety, size compatibility and shape adaptability using rigid grippers presents significant problems. Recent advancements have introduced soft end-effectors that offer enhanced safety and adaptability for gripping parts. However, these soft end-effectors often struggle to maintain the necessary gripping positional accuracy. The purpose of this paper is to design a soft end-effector specifically engineered to address these problems, combining precise gripping capabilities with improved safety, positional accuracy and adaptability to the size and shape of fragile, small-sized components.

A soft finger with multilayer decreasing drive air chambers is designed to achieve the finger bending increasing from the root to the tip of the finger to improve the flexibility of the fingertip. Additionally, a three-finger self-centering configuration is employed, coupled with an expandable structure to increase the gripping range. Furthermore, a theoretical mathematical model of the finger is established. The physical prototype is manufactured and subjected to experimental testing, including gripping tests on small-sized, fragile shaft holes, to validate its operational performance.

The grasping experiments confirm that the designed end-effector can maintain coaxial positioning and meet adaptability requirements when handling fragile components with small-sized shaft holes. Furthermore, the addition of expanding palm structure increases the gripping attitude and enriches the application scene and gripping space.

The design of multilayer decreasing air chamber structure to solve the problem of poor gripping stability and low positional accuracy of soft manipulator; the expandable palm design is introduced to enhance gripping space; and solved the problem of gripping accuracy in the assembly of fragile parts with small-size shafts and holes.

This study aims to investigate the factors responsible for substrate cracking reliability problem in through-glass vias (TGVs), which are critical components for glass-based 2.5 D integration.

Numerical models were used to examine the driving force for substrate cracking in glass interposers due to stress coupling during heating. An analytical solution was used to demonstrate how the energy release rate (ERR) for the glass substrate cracking is affected by the via design and the mismatch in thermal strain. Then, the numerical models were implemented to investigate the design factors effects, such as the pitch distance, via diameter, via pattern, via design, effect from a stress buffer layer and the interposer materials selection on the susceptibility to substrate cracking.

ERR for substrate cracking was found to be directly proportional to the via diameter and the thermal mismatch strain. When a via pattern is implemented for high-density integration, a coupling in the stress fields was identified. This coupling effect was found to depend on the pitch distance, the position of the vias, and the via arrangement, suggesting a via pattern-dependent reliability behavior for glass interposers. Changing the design of the via to an annular shape or a substrate-cored via was found to be a promising approach to reduce the susceptibility to substrate cracking compared to a fully filled solid via. Also, the use of a stress buffer layer, an encouraging design prospect presented for the first time for TGVs in this study, was found to significantly reduce cracking. Finally, alternative via and substrate materials showed lower tendency for substrate cracking, indicating that the reliability of glass interposers can be further enhanced with the implementation of such new materials.

This study signifies the first attempt to comprehensively evaluate the susceptibility to crack formation in glass interposers during heating. Therefore, this study provides new perspectives on how to achieve a significant potential reliability improvement for TGVs.

This study aims to discuss the formation mechanism of members’ emotional attachment to virtual travel communities from an online–offline perspective, focusing on the role of offline tourism experiences.

A questionnaire was designed to survey active travel enthusiast clubs that hold frequent offline tourism activities. A structural equation modeling method was used to estimate the model and test the research hypotheses.

Results demonstrated that offline travel experiences positively influenced online community attachment (i.e., community dependence and identity), and this effect was more pronounced than that of one’s sense of community (i.e., belonging, trust and immersion) on community attachment. Therefore, compared with online interaction, offline travel experiences played a greater part in strengthening virtual community attachment.

The study presents a pioneering effort on understanding how offline activities help shape the community attachment to virtual communities.

本研究从线上-线下的角度探讨了人们对虚拟旅行社区的情感依恋形成机制, 着重关注线下旅游体验的作用。

本研究设计了问卷, 对经常举办线下旅游活动的驴友俱乐部进行了调查。采用结构方程建模方法估计模型并验证研究假设。

结果表明, 线下旅游体验积极地影响着线上社区依恋, 并且这种影响比社区感对社区依恋的影响更为显著。因此, 相较于线上互动, 线下旅游体验在增强虚拟社区依恋方面起到了更大的作用。

本研究首次探讨了线下活动如何帮助塑造虚拟社区成员对虚拟社区的依恋。

Magnetohydrodynamics angular regular sensor (MHD ARS) has been used in many applications for its low noise in wide bandwidth, impact resistance and low power consumption; however, it is unable to estimate the angular velocity at low frequencies such as below 1 Hz. It is difficult to design compensation methods without an exact model. The aim of this study is to investigate a more exact analytical model characterization of the sensor’s frequency response, especially at a low-frequency zone.

A correction coefficient of electromagnetic force in simplified MHD ARS model was introduced according to the theoretical analysis of MHD flow and it was obtained by numerical simulation of electromagnetic force varying with time, space structure and frequency.

To make comparison, the transfer function of the designed MHD ARS in the experiment was identified using Gauss–Newton method with reasonable weights. The identification results confirmed the analytical model. Furthermore, a digital filter was designed based on the analytical model, and the compensation results showed that the frequency limit at low-frequency side was extended from 1 to 0.01 Hz.

The modified analytical model can describe the MHD ARS’s frequency response exactly and may be applied in its low-frequency compensation.

As competition in the graduate labor market intensifies, extracurricular internships have become increasingly popular among university students. This paper explores whether and how students’ evaluation of the higher learning that they have received changes during extracurricular internships.

We interviewed 47 undergraduate students who had extracurricular internships across five Chinese universities. Data were analyzed innovatively through the lens of cross-cultural adaptation theory, which guides us to view internships as a transition from university culture to workplace culture through the stress-adaptation-growth dynamic.

The findings reveal that participants faced stress from multiple sources at the beginning of their internships, which collectively prompted them to adapt proactively to the workplace culture. While acquiring new habits and trying to acculturate into the surrounding work milieu, many participants deculturated from their old habits and student identity, putting aside higher learning. As the adaptation progressed, over half of the participants even began to critique university curricula and depreciate the value of higher learning.

The study offers theoretical insights into internships and the broader university-to-work transition as well as practical implications for universities in balancing learning and employability goals from a novel cross-cultural adaptation perspective.

The recent surge in behavioral studies on the coordination mechanisms in supply chains (SCs) and advanced methods highlights the role of SC coordination (SCC) and behavioral issues associated with improving the performance of the operations. This study aims to critically review the behavioral aspect of channel coordination mechanisms.

Following a systematic literature review methodology, the authors adopt a combination of bibliometric (to reflect the current state of the field), content (using Leximancer data mining software to develop thematic maps) and theory-oriented qualitative analyzes that provide a holistic conceptual framework to unify the literature’s critical concepts.

The analysis confirms the plethora of risk-oriented publications, demonstrating that the second largest category of studies is concerned with social preferences theory. Most studies were based on experiments, followed by analytical modeling, revealing the impact of heuristics and individual preferences in SC decisions and suggesting promising managerial and theoretical avenues for future research.

The study sheds light on behavioral decision theories applied to SC coordination by categorizing the literature based on the adopted theories. The methodological contributions include using automated content analysis and validating the outcome by interviewing leading scholars conducting active research on “behavioral operations management and SC contracts.” The authors also propose several directions for future research based on the research gaps.

In order to improve the accuracy of project cost prediction, considering the limitations of existing models, the construction cost prediction model based on SVM (Standard Support Vector Machine) and LSSVM (Least Squares Support Vector Machine) is put forward.

In the competitive growth and industries 4.0, the prediction in the cost plays a key role.

At the same time, the original data is dimensionality reduced. The processed data are imported into the SVM and LSSVM models for training and prediction respectively, and the prediction results are compared and analyzed and a more reasonable prediction model is selected.

The prediction result is further optimized by parameter optimization. The relative error of the prediction model is within 7%, and the prediction accuracy is high and the result is stable.