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The evaluations of the magnetohydrodynamics angular rate sensor (MHD ARS) in its applications necessitate further improvements in the sensor’s dynamic measurement ability. The magnetic field of the MHD ARS is a key factor in the sensor’s modeling and error analysis. The aim of this study is to illustrate the influence of a non-uniform magnetic field on the sensor.

Numerical simulation is made using ANSYS FLUNET with the magnetic field calculated by 3D-Magnetostatic. The comparison of the simulation results between uniform and non-uniform magnetic fields is made to reveal and explain the effects of magnetic field inhomogeneity (MFI) on the flow and electric field in detail. Two different structures with different MFIs are designed to confirm the MFI effect on the sensor’s output in simulation and experiment. A cross-correlation experiment and an adaptive filter are carried out to extract the signal to identify the error of the sensor output caused by MFI.

The MFI effect on the flow field in MHD ARS is found to be insignificant, while its effect on the electric potential is considerable. The comparisons between two kinds of MHD ARS in numerical simulation and experiment show that the MFI effect on the sensor error can be identified by fitting the sensor output. The deviation is mainly generated at the peaks and valleys of an angular vibration.

The study of the MHD ARS under the influence of a non-uniform magnetic field can offer an understanding of the MFI effect on the sensor and an evaluation method of the sensor error caused by the MFI effect.

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.

Robotic arms play a crucial role in various industrial operations, such as sorting, assembly, handling and spraying. However, traditional robotic arm control algorithms often struggle to adapt when faced with the challenge of dynamic obstacles. This paper aims to propose a dynamic obstacle avoidance method based on reinforcement learning to address real-time processing of dynamic obstacles.

This paper introduces an innovative method that introduces a feature extraction network that integrates gating mechanisms on the basis of traditional reinforcement learning algorithms. Additionally, an adaptive dynamic reward mechanism is designed to optimize the obstacle avoidance strategy.

Validation through the CoppeliaSim simulation environment and on-site testing has demonstrated the method's capability to effectively evade randomly moving obstacles, with a significant improvement in the convergence speed compared to traditional algorithms.

The proposed dynamic obstacle avoidance method based on Reinforcement Learning not only accomplishes the task of dynamic obstacle avoidance efficiently but also offers a distinct advantage in terms of convergence speed. This approach provides a novel solution to the obstacle avoidance methods for robotic arms.

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。

The existing literature has a lack of modeling of procedural fairness concerns in the supply chain level. This paper aims to investigate how procedural fairness concerns affect channel decisions, performance and coordination.

This paper considers a supply chain consisting of one supplier and one retailer who have procedural fairness concerns in a classic Stackelberg game setting. The model is set in sales promotional environment. According to the existing literature, engagement is used to depict fair process. Some findings are made through analyzing respective decisions of the supplier and the retailer under the influence of procedural fairness concerns.

The results show that the channel efficiency can be improved when the retailer exhibits procedural fairness concerns, but if the aversion to unfair process exceeds a certain threshold, the retailer cannot benefit from it. Besides, the retailer profits more when he cares about distributional fairness, although the whole channel surplus can be improved by procedural fairness concerns.

This is the first paper to study the influences of procedural fairness concerns on supply chain decisions and channel performance. Finally, a mechanism combining a wholesale price contract with slotting allowances is proposed to coordinate the supply chain.

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.

Glass is a promising interposer substrate for 2.5 D integration; yet detailed analysis of the interfacial reliability of through-glass vias (TGVs) has been lacking. The purpose of this paper is to investigate the design and material factors responsible for the interfacial delamination in TGVs and identify methods to improve reliability.

The interfacial reliability of TGVs is studied both analytically and numerically. An analytical solution is presented to show the dependence of the energy release rate (ERR) for interfacial delamination on the via design and the thermal mismatch strain. Then, finite element analysis (FEA) is used to investigate the influence of detailed design and material factors, including the pitch distance, via aspect ratio, via geometry and the glass and via materials, on the susceptibility to interfacial delamination.

ERR for interfacial delamination is directly proportional to the via diameter and the thermal mismatch strain. Thinner wafers with smaller aspect ratios show larger ERRs. Changing the via geometry from a fully filled via to an annular via leads to lower ERR. FEA results also show that certain material combinations have lower thermal mismatch strains, thus less prone to delamination.

The results and approach presented in this paper can guide the design and development of more reliable 2.5 D glass interposers.

This paper represents the first attempt to comprehensively evaluate the impact of design and material selection on the interfacial reliability of TGVs.

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.

Document management is growing in importance proportionate to the growth of unstructured data, and its applications are increasing from process benchmarking to customer relationship management and so on. The purpose of this paper is to improve important components of document management that is keyword extraction and document clustering. It is achieved through knowledge extraction by updating the phrase document matrix. The objective is to manage documents by extending the phrase document matrix and achieve refined clusters. The study achieves consistency in cluster quality in spite of the increasing size of data set. Domain independence of the proposed method is tested and compared with other methods.

In this paper, a synset-based phrase document matrix construction method is proposed where semantically similar phrases are grouped to reduce the dimension curse. When a large collection of documents is to be processed, it includes some documents that are very much related to the topic of interest known as model documents and also the documents that deviate from the topic of interest. These non-relevant documents may affect the cluster quality. The first step in knowledge extraction from the unstructured textual data is converting it into structured form either as term frequency-inverse document frequency matrix or as phrase document matrix. Once in structured form, a range of mining algorithms from classification to clustering can be applied.

In the enhanced approach, the model documents are used to extract key phrases with synset groups, whereas the other documents participate in the construction of the feature matrix. It gives a better feature vector representation and improved cluster quality.

Various applications that require managing of unstructured documents can use this approach by specifically incorporating the domain knowledge with a thesaurus.

Experiment pertaining to the academic domain is presented that categorizes research papers according to the context and topic, and this will help academicians to organize and build knowledge in a better way. The grouping and feature extraction for resume data can facilitate the candidate selection process.

Applications like knowledge management, clustering of search engine results, different recommender systems like hotel recommender, task recommender, and so on, will benefit from this study. Hence, the study contributes to improving document management in business domains or areas of interest of its users from various strata’s of society.

The study proposed an improvement to document management approach that can be applied in various domains. The efficacy of the proposed approach and its enhancement is validated on three different data sets of well-articulated documents from data sets such as biography, resume and research papers. These results can be used for benchmarking further work carried out in these areas.

The purpose of this paper is to study the microstructure and mechanical behaviour of smaller microbumps for high density solder interconnects.

The microstructure was analyzed by scanning electron microscopy and electron backscatter diffraction tests to determine the Sn grain number of the resultant microbumps. The nanomechanical properties of Sn microbumps were investigated by the nanoindentation and shearing tests to understand the failure mechanism and assess the reliability of ultra-high density solder interconnects with numbered grains.

Only one Sn grain is observed in the interconnect matrix when the microbumps are miniaturized to 40 μm or less. Because of the body-centred tetragonal lattice of ß-Sn unit cell, the mechanical properties of the one-grain Sn microbumps are remarkably anisotropic, which are proved by the difference of the elastic modulus and the stiffness in the different orientations. The shearing tests show that the one-grain Sn microbump has a typical brittle sliding fracture of monocrystal at different shearing speeds.

The paper provides a comparable study for the performance of the bigger solder joints and also makes preliminary research on the microstructure and mechanical behaviour of Sn microbumps with the diameter of 40 μm.

The findings in this paper provide methods of microstructure study by combination of EBSD test and metallographic analysis, mechanical study by combination of nanoindentation test and shearing test, which can provide good guidelines for other smaller microbumps. The strain rate sensitivity exponent of the one-grain Sn microbumps is consistent with the Pb-free bulk solder. This implies that the one-grain Sn microbump has a comparable flow stress to Sn37Pb solder, which is beneficial for Pb-free replacement in higher density microelectronic packaging.