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This paper aims to investigate the moisture diffusion behavior in a system-in-package module systematically by moisture-thermalmechanical-coupled finite element modeling with different structure parameters under increasingly harsh environment.

A finite element model for a system-in-package module was built with moisture-thermal-mechanical-coupled effects to study the subsequences of hygrothermal conditions.

It was found in this paper that the moisture diffusion path was mainly dominated by hygrothermal conditions, though structure parameters can affect the moisture distribution. At lower temperatures (30°C~85°C), the direction of moisture diffusion was from the periphery to the center of the module, which was commonly found in simulations and literatures. However, at relatively higher temperatures (125°C~220°C), the diffusion was from printed circuit board (PCB) to EMC due to the concentration gradient from PCB to EMC across the EMC/PCB interface. It was also found that there exists a critical thickness for EMC and PCB during the moisture diffusion. When the thickness of EMC or PCB increased to a certain value, the diffusion of moisture reached a stable state, and the concentration on the die surface in the packaging module hardly changed. A quantified correlation between the moisture diffusion coefficient and the critical thickness was then proposed for structure parameter optimization in the design of system-in-package module.

The different moisture diffusion behaviors at low and high temperatures have seldom been reported before. This work can facilitate the understanding of moisture diffusion within a package and offer some methods about minimizing its effect by design optimization.

Travel companies are increasingly hosting online communities to extend their initiatives of customer relationship management and gain additional insight into their business. While the benefits to companies from hosting online communities are clear, another closely related issue has not been given comparative attention: Why do customers engage voluntarily in online travel communities? The purpose of this paper is to answer the question by developing and testing a conceptual model that exploring the influence of socialization interactions on customer engagement with the community.

Hypotheses were tested by applying structural equation modeling based on survey data collected from an online travel community (n=665).

The results supported the research hypotheses and demonstrated that socialization interactions (i.e. information and social exchange) in the online travel community are important catalysts for customer engagement.

The contribution of this study is twofold. First, from a theoretical perspective, it offers new insights into the conceptualization of customer engagement and its antecedents in the context of the online travel community. Second, from a pragmatic perspective, the conceptual model derived from this research aids practitioners in stimulating customer engagement from the perspective of socialization interactions.

This study aims to solve the problems of ambiguous localization, large calculation, poor real-time and limited applicability of bolt thread defect detection.

First, the acquired ultrasound image is used to acquire the larger area of the image, which is set as the compliant threaded area. Second, based on the determined coordinates of the center point in each selected region, the set of coordinates on the left and right sides of the bolts is acquired by DBSCAN method with parameters eps and MinPts, which is determined by data set dimension D and the k-distance curve. Finally, the defect detection boundary line fitting is completed using the acquired coordinate set, and the relationship between the distance from each detection point to the curve and d, which is obtained from the measurement of the standard bolt sample with known thread defect, is used to locate the bolt thread defect simultaneously.

In this paper, the bolt thread defect detection method with ultrasonic image is proposed; meanwhile, the ultrasonic image acquisition system is designed to complete the real-time localization of bolt thread defects.

The detection results show that the method can effectively detect bolt thread defects and locate the bolt thread defect location with wide applicability, small calculation and good real-time performance.

The purpose of this paper is to present a transition detector (TD)-based radiation hardened flip-flop (TDRH-FF) for single event upset (SEU).

With SEU recovery and single event transient (SET) detector mechanism, the TDRH-FF can tolerate SEU during hold mode and generate a warning signal for architecture-level recovery during transport mode when input signal contains SET. Evaluation results show that the TDRH-FF outperforms comparable comprehensive performance.

Simulation results show that 1) the mean pulse width of the correction glitches (at full width half maximum) of TDRH-FF is less than 10 ps; 2) the area overhead of TDRH-FF is similar to the EVFERST-FF, BISER-FF and DNURHL-FF; 3) TDRH-FF has the same average power consumption as SETTOF, and moderate PDP and Ps values among these compared FFs.

In this paper, a TD-based TDRH-FF is proposed to solve the problems in the previous design. And the main contributions of the proposed TDRH-FF are summarized: Minimum size transistors are used in the proposed TD which leads to a considerable decrease in area overheads and propagation delay (resulting in an ignorable correction glitch); and compared with other radiation hardened flip-flop, TDRH-FF outperforms comparable comprehensive performance.

This paper aims to answer following three important but not well-answered or unanswered questions in the extant trust literatures: What is the true magnitude that trust impacts on performance? Is there any consistency among the effects of trust on performance at different levels? How does vertical distance affect the trust-performance relationship?

It captures the law between trust and performance at different levels by conducting a meta-analytic examination consisting of 238 independent empirical studies, 586 effect sizes and 110,576 independent samples.

It makes a periodic conclusion that trust significantly promotes performance. Specifically, trust not only has stronger positive correlation with team performance than individual and organizational performance inside organization, but also strongly facilitates organizational performance between organizations. Moreover, consistency exits in the effects of trust on performance at different levels. On one hand, trust has stronger positive correlation with performance of contextual type than performance of innovative type than performance of task type at different levels. On the other hand, promotion effect of trust on performance strengthens when the vertical distance between trustors and trustees diminishes. Additionally, three potential moderators including publication status, measurement tool and common method variance moderate the focused relation, but moderating effect is not thorough for regional culture. Moderating directions of the above four potential moderators are highly consistent.

This paper answers the three important but not well-answered or unanswered questions.

In the online marketing context, virtual reality (VR) has been used to display products and shopping environment, which effectively enhances the consumer experience. VR technology can not only recreate scenes similar to the real world (virtual authenticity, VA) but also create fictitious and desirable scenes that do not exist in the real world (virtual ideality, VI). The differences between VA and VI in influencing consumers' responses have not been fully understood. In addition, social signals have appeared in VR apps. However, the role of social signals in a VR context has rarely been studied. To fill the gaps in the literature, this study investigates the roles of VA and VI in shaping consumers' responses, as well as whether and how their effectiveness in shaping consumers' responses is influenced by social signals.

A VR real estate service platform was selected as the experimental platform, and two experiments were conducted to test the hypotheses. The ANOVAs and regressions were used for data analysis.

Results show that VA leads to a higher level of perceived diagnosticity than VI, whereas VI leads to a higher level of inspiration than VA; perceived diagnosticity and inspiration positively affect visit intention. Furthermore, the relationship between consumers' perceived diagnosticity, inspiration and visit intention is moderated by the presence of social signals.

The study revealed the differences between VA and VI in shaping consumers' responses, as well as the effect of social signals in VR environment, which provide a new perspective for future VR research in the context of interactive marketing.

The purpose of this paper is to reveal the inner mechanisms of the role of industrial internet platforms in empowering the digital transformation of SMEs. This ROOTCLOUD-based case study shows that knowledge integration and knowledge sharing and driving play essential empowering roles in the impact of industrial internet platforms on the digital transformation of SMEs. The industrial internet platform promotes knowledge integration on the supply side, empowers cross-domain knowledge sharing and shapes the knowledge-driven digital supply chain system in the digital transformation processes of SMEs.

This paper presents a qualitative analysis of the knowledge empowerment role played by industrial internet platforms in the digital transformation process of SMEs. Based on theoretical sampling, this paper selects ROOTCLOUD as a typical case to analyse the implementation mechanism of the industrial internet platform in solving the digital transformation problems and challenges faced by SMEs.

Knowledge management (knowledge integration, sharing and driving) plays an important intermediary role between the empowerment of industrial internet platform and the digital transformation of SMEs. Specifically, the industrial internet platform empowers SMEs with knowledge, empowers supply-side knowledge integration, empowers cross-domain knowledge sharing and facilitates the formation of knowledge-driven supply chain systems.

This study clarifies the mechanism underlying the digital transformation of SMEs empowered by industrial internet platforms, that is, the empowerment of industrial internet platform enhances the level of knowledge integration and sharing of SMEs, thus improving the effectiveness of SMEs in achieving digital transformation. Further empirical studies should be conducted on the above mechanism.

Based on the theoretical perspective of knowledge management, this paper discusses the problems and challenges faced in the digital transformation of SMEs through knowledge empowerment by the industrial internet platform ROOTCLOUD and proposes that knowledge empowerment in the industrial internet platform helps supply-side knowledge integration, promotes cross-domain knowledge sharing and contributes to forming a knowledge-driven supply chain system, thereby promoting the digital transformation of SMEs. System architects and relevant policy departments should pay attention to data-centred system construction, improve the construction of data-based collaborative application ecology and encourage industrial internet platforms to provide more targeted knowledge empowerment solutions for SMEs.

The purpose of this paper is to present a novel registration method for augmented reality (AR) systems based on robust estimation of trifocal tensor using point and line correspondence simultaneously.

The proposed method distinguishes itself in following three ways: first, to establish the world coordinate system, the restriction that the four specified points must form an approximate square is relaxed, the only requirement is that these four points should not be collinear. Second, besides feature points, line segments are also used to calculate the needed trifocal tensors. The registration process can still be achieved even without the use of feature points. Third, to estimate trifocal tensors precisely, progressive sample consensus (PROSAC) is used instead of random sample consensus to remove outliers.

As shown in the experiments, the proposed method really enhances the usability of this system. To calculate trifocal tensor, a PROSAC based algebraic minimization algorithm is put forward which improves the accuracy and reduces the computation complexity.

In current system, it is stipulated that there is no large rotation of the user's head relative to the registration scenes, because the NCC will degrade when there is a large rotation between images.

A more robust feature matching strategy is needed. Treating feature matching as a classification problem may be a good choice.

This paper presents a novel registration approach for AR system.

This study aims to evaluate the dry-sliding tribological properties of fine-grained tin–bronze alloy under reciprocating sliding conditions.

A fine-grained tin–bronze alloy was processed by multiaxial forging (MAF) and annealing treatment. Friction and wear experiments were conducted on a reciprocating sliding tribometer. Microstructure, tensile mechanical properties, hardness, wear rate, friction coefficient and wear morphologies of coarse-grained sample, MAF sample and MAF and annealing sample were compared.

After MAF, the strength and hardness increased distinctly, but the elongation decreased. The wear rate is increased, though friction coefficient is lower. Weaker work hardening leads up to higher sliding wear rate. After MAF and annealing, the alloy has higher strength, hardness and elongation. Lower wear rate of the alloy is correlated with the higher hardness, elongation and work hardening. The adhesion wear and abrasive wear are the primary wear mechanism.

It was found that the fine-grained alloy shows lower sliding wear rate only by combining severe plastic deformation with heat treatment. The process of MAF and annealing is useful in improving the wear resistance of tin–bronze alloy.