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As the limited energy of wireless sensor networks (WSNs), energy-efficient data-gathering algorithms are required. This paper proposes a compressive data-gathering algorithm based on double sparse structure dictionary learning (DSSDL). The purpose of this paper is to reduce the energy consumption of WSNs.

The historical data is used to construct a sparse representation base. In the dictionary-learning stage, the sparse representation matrix is decomposed into the product of double sparse matrices. Then, in the update stage of the dictionary, the sparse representation matrix is orthogonalized and unitized. The finally obtained double sparse structure dictionary is applied to the compressive data gathering in WSNs.

The dictionary obtained by the proposed algorithm has better sparse representation ability. The experimental results show that, the sparse representation error can be reduced by at least 3.6% compared with other dictionaries. In addition, the better sparse representation ability makes the WSNs achieve less measurement times under the same accuracy of data gathering, which means more energy saving. According to the results of simulation, the proposed algorithm can reduce the energy consumption by at least 2.7% compared with other compressive data-gathering methods under the same data-gathering accuracy.

In this paper, the double sparse structure dictionary is introduced into the compressive data-gathering algorithm in WSNs. The experimental results indicate that the proposed algorithm has good performance on energy consumption and sparse representation.

A high-precision gyroscope is an important tool for accurate positioning, and the amplitude stability and frequency tracking ability of the drive control system are important and necessary conditions to ensure the precision of micro-electro-mechanical systems (MEMS) gyroscopes. To improve the precision of MEMS gyroscopes, this paper proposes a method to improve the amplitude stability and frequency tracking ability of a drive control system.

A frequency tracking loop and an amplitude control loop are proposed to improve the frequency tracking ability and amplitude stability of the drive control system for a MEMS gyroscopes. The frequency tracking loop mainly includes a phase detector, a frequency detector and a loop filter. And, the amplitude control loop mainly includes an amplitude detector, a low-pass filter and an amplitude control module. The simulation studies on the frequency tracking loop, amplitude control loop and drive control system composed of these two loops are implemented. The corresponding digital drive control algorithm is realized by the Verilog hardware description language, which is downloaded to the application-specific integrated circuits (ASIC) platform to verify the performances of the proposed method.

The simulation experiments in Matlab/Simulink and tests on the ASIC platform verify that the designed drive control system can keep the amplitude stable and track the driving frequency in real time with high precision.

This study shows a way to design and realize a drive control system for MEMS gyroscopes to improve their tracking ability. It is helpful for improving the precision of MEMS gyroscopes.

The purpose of this paper is to unpack the “black box” of the relationship between contract and inter-organizational trust, both theoretically and empirically. Two mediators, namely perceived safeguard and restriction, are identified to build up two seemingly contrary possible paths between contract and trust from current literature. Both paths are tested in the context of Chinese construction industry due to our access to sample.

A survey of 295 contractor-subcontractor relationships from Chinese construction industry was conducted. A three-step multiple regression model was employed to test the mediating effect of perceived safeguard and restriction. Then, a hierarchical regression model was used to test the possible moderating effect of bilateral transaction-specific investment.

The empirical results support the mediating effect of perceived safeguard between contract and trust in the construction subcontracting industry. Bilateral transaction-specific investments enhance the positive effect of contract on safeguard perception.

Theoretically, this study contributes to governance literature by opening up the “black box” of the relationship between contract and trust. It provides a better understanding of how and when contract complexity impacts trust, instead of simply focusing on whether contract and trust act as complements or substitutes. Practically, this study provides guidelines for construction firms to decide the degree of contract complexity under various degrees of bilateral transaction-specific investments to enhance the other party’s trust, so as to improve performance outcomes.

This study aims to clarify the relationship between the coefficient of friction (COF) and temperature of aluminum-based brake discs.

Three friction blocks with different COFs are examined by a TM-I-type reduced-scale inertial braking dynamometer. On this basis, the thermo-mechanically coupled model of friction pairs is established to study the evolution of brake disc temperature under different COFs using ADINA software.

Results indicate that the calculated disc temperature field matches the experimental well. The effect of COF on the peak temperature is magnified by the braking speed. With the COF increasing, the rise rate of instantaneous peak temperature is accelerated, and the dynamic equilibrium period and cooling-down period are observed in advance. The increase in COF promotes the area ratio of the high-temperature zone and the maximum radial temperature difference. When the COF is increased from 0.245 to 0.359 and 0.434 at 140 km/h, the area ratio of high-temperature zone increases from 12% to 44% and 49% and the maximum radial temperature difference increases from 56°C to 75°C and 83°C. The sensitiveness of the axial temperature difference to the COF is related to the braking time. The maximum axial temperature difference increases with COF in the early stages of braking, while it is hardly sensitive to the COF in the later stages of braking.

The effect of COF on the aluminum-based brake disc temperature is revealed, providing a theoretical reference for the popularization of aluminum-based brake discs and the selection of matching brake pads.

This study aims to clarify the relationship of friction material type and brake disc temperature through braking experiment.

The braking performances of resin materials (RM), semimetallic materials (SM) and copper-based powder metallurgy materials (PM) friction blocks mating with forged steel brake disc were examined based on TM-I-type reduced-scale inertial braking dynamometer. The brake disc surface temperature was recorded by infrared thermal camera during braking.

Experimental results indicate that the thermal wear resistance of three friction materials differs with mental content, resulting in the deviation of pad-disc system contact state during braking, thus forming different temperature distribution on the brake disc surface. The peak temperature on the disc face of RM (190°C) is 36.6% and 45.4% lower than that of PM (300°C) and SM (348°C) at 160 km/h. The maximum radial temperature deviation of PM (35°C) is approximately three times than that of RM (12°C) and 40% higher than that of SM (25°C) at 50 km/h, whereas the maximum temperature deviation of SM (97°C) is six times than that of RM (16°C) and 31% higher than that of PM (74°C) at 160 km/h.

The effect of friction material type on the disc surface temperature distribution is revealed, which provides a meaningful reference for the design of brake friction pairs and choice of brake pad materials.

Construction insurance has been advocated as a useful financial means to transfer risks and mitigate potential project losses. However, there is a general reluctance to purchase construction insurance in China. The purpose of this paper is to develop an extended theory of planned behavior (TPB) model to understand and predict contractors’ construction insurance purchasing intention.

Quantitative data were collected through a questionnaire survey. The respondents comprise 130 project directors/managers and contract managers/administrators who were involved in or familiar with the construction insurance purchasing or managing. Data were analyzed using structural equation modeling.

This study developed an extended TPB model to explain the contractors’ intention formation. The results indicated that the insurance purchasing intention was mainly influenced by attitudes and subjective norm, rather than perceived behavioral control. The analyses also revealed that the added variables (risk perception and past experience) had a significant impact on the attitudes and perceived behavioral control.

This study identified the factors leading to Chinese contractors’ low willingness to purchase construction insurance by extending the TPB model to the context of construction insurance purchasing. The extended TPB model may serve as a theoretical framework and basis for the Chinese contractors, insurers, and regulators to understand the root causes of contractors’ low willingness to purchase construction insurance and make joint efforts to address the risks and insurance in the construction industry.

Cultural differences have been frequently cited as a major source of risks for international joint ventures (IJVs). Cultural differences may cause extensive conflicts in technology, norms and emotion among the international joint venture (IJV) partners. The purpose of this study is to explore the interactive effects of national culture differences (NCDs) and conflict management approaches on the performance of international construction joint ventures (ICJV).

Data were collected using a questionnaire survey method with 143 valid responses. Partial least squares structural equation modeling (PLS-SEM) was used to test the research hypotheses.

It was found that ICJV performance declined with a high degree of NCDs. The negative effect of NCDs on ICJV performance was mitigated by adopting the cooperative conflict management approach; while it was aggravated by adopting the competitive conflict management approach. The findings may provide an alternative way (i.e. adopting the cooperative conflict management approach rather than avoiding or competitive approaches) to address the cultural conflicts in the multicultural project management teams.

Firstly, as NCD negatively impacts performance of ICJVs, project managers should pay attention to cultural issues and learn how to manage them; Secondly, as cooperative and competitive conflict management approaches have different moderating effects on the relationship between NCD and ICJV performance, project managers must choose appropriate conflict management styles in multination teams. Thirdly, as the avoiding approach has no significant moderating effect on the negative relationship between NCD and ICJV performance, it is important for Chinese partners not to employ avoiding approach to deal with conflicts in ICJV.

This study uniquely adds to the literature on cultural issues in managing ICJVs by integrating the moderating effects of conflict management approaches. The interactive effects of conflict management approaches and national cultural differences on ICJV project performance may contribute to the theories regarding conflict management theory in the context of cross-cultural management.

Corporate philanthropy is increasingly a vital decision-making basis for consumers to purchase and establish relationships with enterprises. However, few studies have examined corporate philanthropy from the perspective of community evolution. To address this gap, this study aims to provide a more in-depth and holistic investigation of corporate philanthropy by examining the evolution of social media brand communities caused by corporate philanthropy and the characteristics of consumer interactive behavior.

Web crawlers developed by Python were employed to collect data of ERKE from Sina Weibo (the Chinese equivalent of Twitter). A total of 2,736 posts and 7,774 comments were collected and investigated using social network and sentiment tendency analyses.

The results showed that the evolution of the social media brand community presented a prominent three-stage characteristic influenced by corporate philanthropy. The findings not only support the benefits of corporate philanthropy but also show the possible disadvantages. Besides, this study further concluded the characteristics of consumer interactive behavior in the social media brand community.

This paper addresses an attractive and practical issue related to the impact of corporate philanthropy. Moreover, this study is one of the first studies to examine the impact of corporate philanthropy in the context of the social media brand community. The findings of this study will provide a valuable reference for community operations and practitioners of brands.

Seit Gründung des EUROPÄISCHEN TOURISMUS INSTITUTS GmbH (ETI) an der Universität Trier stellt der Kulturtourismus einen der Forschungs‐ und Beratungsschwerpunkte innerhalb der Institutsarbeit dar. Im Jahr 1992 führte das ETI mit Unterstützung der EG‐Kommission das Forschungsprojekt “Kulturtourismus in Europa/Demonstrationsvorhaben im Bi!dungs‐/Kulturtourismus” durch, dessen Ergebnisse auf dem Internationalen Symposium “Kulturtourismus in Europa: Wachstum ohne Grenzen?” im Juni 1992 in Trier vorgestellt und im weiteren dokumentiert wurden (vgl. Becker/ Steinecke 1993; Steinecke 1993a, 1993b).

The objective of this research is to develop a decision method that can generate appropriate risk response strategies for international construction project managers (PMs) and allow these strategies to reflect their different risk preferences.

The optimal model approach is adopted. A credibility-based fuzzy chance constrained programming (CFCCP) model is developed, which simultaneously minimizes the expected losses of risk events and total costs of risk response. To solve this multi-objective model, a fuzzy interactive solution method is used. Moreover, the model performance is demonstrated by a real international industrial plant project. In addition, a sensitivity analysis of the model is conducted.

The result of the sensitivity analysis indicates that PMs with a greater risk aversion can lead to a higher mitigation ratio of expected losses of risk events and a higher total cost of risk response.

This research provides contractors with an effective decision-making model to develop a project risk response plan, and it will assist contractors to minimize risk losses and enhance the project performance in the international construction market.

Previous studies overlook the risk preference, which is an important behavioral factor influencing decisions in risk response strategy selection. This research proposed a novel risk response strategy selection decision method that considers different attitudes toward risk among decision makers.