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This paper aims to focus on establishing the bond-slip constitutive relation of mortar anchor under high loading rates by the dynamic pull-out test.

Self-made specimens were made for the dynamic pull-out test to explore the bond performance of mortar anchor, and the bond-slip constitutive relation of mortar anchor under high loading rates was established according to the analysis of test data.

During the loading process, the position of the peak bond stress was observed to translate to the free end. The bearing capacity of the mortar anchor was enhanced to some extent due to the increase of the loading rate.

The bond-slip constitutive relation of mortar anchor under high loading rates was established with the introduction of the position function and dynamic-load expanded coefficient.

In China, external supervision on construction safety mainly comes from the government and supervision engineers (SEs). However, the construction safety supervisory mechanism (CSSM) contains some dilemmas affecting the improvement of safety performance, such as the declining impact of SEs, the increasing rent-seeking behaviors of contractor and excessive government interference. This study aims to depict and analyze the CSSM in China from an evolutionary game view. The objectives are to understand the supervision strategy and evolutionary behaviors of different stakeholders, propose suggestions for improving safety performance and help the key safety supervision stakeholders, especially the government, formulate a suitable safety supervision strategy.

This research uses tripartite dynamic evolutionary game theory to study the CSSM in China and solve the stable equilibrium solution using system dynamics.

This study has revealed the game relationship of construction safety supervision mechanisms in China and solved the stable equilibrium solution. The results prove that a supervision engineer (SE) plays a crucial role in the CSSM, and “supervision engineer useless” is an unreasonable assertion. For government supervision agency (GSA), excessive inspection and free-market regulation are neither wise strategies. GSA can reduce the inspection frequency when general contractors (GCs) input high safety investments and SEs implement responsible supervision. But keeping proper government supervision to avoid GC's unlawful behaviors and SE's rent-seeking is indispensable. In addition, excessive governmental supervision will weaken SE's role, so the government should transfer some supervision powers to SE.

This study focuses on the dynamic evolution process between GSA, GC and SE. This method is different from most research that neglected the dynamic characteristic of system and game solution stability. The research methods not only contribute to construction safety supervision policy-making in China but also help to improve supervision efficiency in other countries and other fields.

The purpose of this paper is to quickly manufacture full Cu₃Sn-microporous copper composite joints for high-temperature power electronics applications and study the microstructure evolution and the shear strength of Cu₃Sn at different bonding times.

In this paper, a novel structure of Cu/composite solder sheet/Cu was designed. The composite solder sheet was made of microporous copper filled with Sn. The composite joint was bonded by thermo-compression bonding under pressure of 0.6 MPa at 300°C. The microstructure evolution and the growth behavior of Cu₃Sn at different bonding times were observed by electron microscope and metallographic microscope. The shear strength of the joint was measured by shear machine.

At initial bonding stage the copper atoms in the substrate and the copper atoms in the microporous copper dissolved into the liquid Sn. Then the scallop-liked Cu₆Sn₅ phases formed at the interface of liquid Sn/microporous copper and liquid Sn/Cu substrates. During the liquid Sn changing to Cu₆Sn₅ phases, Cu₃Sn phases formed and grew at the interface of Cu₆Sn₅/Cu substrates and Cu₆Sn₅/microporous copper. After that the Cu₃Sn phases continued to grow and the Cu₃Sn-microporous copper composite joint with a thickness of 100 µm was successfully obtained. The growth rule of Cu₃Sn was parabolic growth. The shear strength of the composite joints was about 155 MPa.

This paper presents a novel full Cu₃Sn-microporous copper composite joint with high shear strength for high-temperature applications based on transient liquid phase bonding. The microstructure evolution and the growth behavior of Cu₃Sn in the composite joints were studied. The shear strength and the fracture mechanism of the composite joints were studied.

Aiming to investigate the direct and indirect effects of community involvement on residents’ life satisfaction, this study builds a conceptual framework through the mediation effect of perceived impacts and trust in government based on social exchange theory. The moderating effect of place attachment among these variables is proposed and empirically examined.

The conceptual model and causal relationships were estimated by adopting structural equation modeling, a serial mediation and moderation analysis. A total of 362 valid questionnaire data from residents in five rural tourism communities of China were collected and used for data analysis.

The results indicate that residents’ community involvement directly influences their life satisfaction and indirectly through perceived benefits and trust in government. Place attachment is also found to moderate the effect of community involvement on residents’ life satisfaction.

This study tests the effect of community involvement on residents’ life satisfaction that evolves from linking community involvement to perceived tourism impacts and trust in government to increase life satisfaction within the rural tourism context. It simultaneously detects place attachment as a moderating variable. The findings of this study can provide valuable insights for rural tourism managers to improve residents’ life satisfaction.

为了探究社区参与对居民生活满意度的直接和间接影响, 本研究基于社会交换理论构建了通过感知影响和政府信任作为中介效应的理论模型。同时, 提出并实证检验了地方依恋在这些变量关系中的调节作用。

采用结构方程模型和一系列的中介和调节分析来估计概念模型和变量之间的因果关系。从中国五个乡村旅游社区收集了362份有效问卷并进行数据分析。

结果显示, 居民的社区参与不仅直接影响他们的生活满意度, 并且通过感知收益和政府信任对他们的生活满意度产生间接影响。研究还发现,地方依恋可以调节社区参与对居民生活满意度的影响关系。

本研究探讨了乡村旅游可持续发展中社区参与对生活满意度的影响, 这种影响从链接社区参与与旅游感知效应到政府信任, 从而提高生活满意度,同时检验了地方依恋的调节作用。本研究能够为乡村旅游管理者提高居民生活满意度提供有价值的建议。

Con el objetivo de investigar los efectos directos e indirectos de la participación de la comunidad en la satisfacción con la vida de los residentes, este estudio construye un marco conceptual a través del efecto mediador de los impactos percibidos y la confianza en el gobierno basado en la teoría del intercambio social. Se propone y examina empíricamente el efecto moderador del apego local entre estas variables.

La relación causal entre el modelo conceptual y la estructura se estima a través del modelo de ecuación estructural, y se lleva a cabo una serie de análisis de mediación y regulación. Los datos fueron recolectados de 362 cuestionarios válidos de cinco comunidades de turismo rural en China.

Los resultados muestran que la participación comunitaria de los residentes influye directamente en su satisfacción con la vida, e indirectamente a través de sus ingresos percibidos y la confianza en el Gobierno. El estudio también encontró que el apego local puede regular la participación de la comunidad en la satisfacción de los residentes con la vida.

Este estudio explora el impacto de la participación comunitaria en la satisfacción con la vida en el desarrollo sostenible del turismo rural, que va desde la vinculación de la participación comunitaria y la percepción turística hasta la confianza del Gobierno, mejorando así la satisfacción con la vida. Al mismo tiempo, se examina la función reguladora del apego local. Los resultados de este estudio proporcionan información de referencia valiosa para que los administradores del turismo rural mejoren la satisfacción de los residentes con la vida.

This paper aims to prepare an oil-impregnated porous polytetrafluoroethylene (PTFE) composite with advanced tribological properties using citric acid as a novel pore-forming agent.

Citric acid (CA) was used to form pores in PTFE, and then oil-impregnated PTFE composites were prepared. The pore-forming efficiency of CA was evaluated. The possible mechanism of lubrication was proposed according to the tribological properties.

The results show CA is an efficient pore-forming agent and completely removed, and the porosity of the PTFE increases with the increase of the CA content. The oil-impregnated porous PTFE exhibits an excellent tribological performance, an increased wear resistance of 77.29% was realized in comparison with neat PTFE.

This study enhances understanding of the lubrication mechanism of oil-impregnated porous polymers and guides for their tribological applications.

This study aims to provide supplements to the research on digital human avatar (DHA) and suggestions for brands to use DHA appropriately to build brand fans effect.

On the basis of integrating Avatar theory and Stimulus-organism-response theory, this study obtains data from 733 Chinese respondents aged 18–25 and uses regression analysis and bootstrap analysis to verify the relationships among the variables: DHA characteristics (form realism, behavioral realism and brand alignment) as the independent variables, brand fans effect as the dependent variable, consumer positive emotion as the mediating variable and product type (experience vs search) as the moderating variable.

The results show that DHA characteristics positively influence brand fans effect and consumer positive emotion, consumer positive emotion positively influences brand fans effect and consumer positive emotion plays a mediating role. Meanwhile, for experience products, the impact of DHA’s form realism and behavioral realism on consumer positive emotion is higher than that of brand alignment; for search products, the impact of DHA’s brand alignment on consumer positive emotion is higher than that of form realism and behavioral realism.

This study enriches and expands the empirical research perspectives and conclusions in the DHA field, improves its research framework and provides suggestions for brands to appropriately use DHA to build brand fans effect.

Human-induced marine environmental noise, such as commercial shipping and seismic exploration, is concentrated in the low-frequency range. Meanwhile, low-frequency sound signals can achieve long-distance propagation in water. To meet the requirements of long-distance underwater detection and communication, this paper aims to propose an micro-electro-mechanical system (MEMS) flexible conformal hydrophone for low-frequency underwater acoustic signals. The substrate of the proposed hydrophone is polyimide, with silicon as the piezoresistive unit.

This paper proposes a MEMS heterojunction integration process for preparing flexible conformal hydrophones. In addition, sensors prepared based on this process are non-contact flexible sensors that can detect weak signals or small deformations.

The experimental results indicate that making devices with this process cannot only achieve heterogeneous integration of silicon film, metal wire and polyimide, but also allow for customized positions of the silicon film as needed. The success rate of silicon film transfer printing is over 95%. When a stress of 1 Pa is applied on the x-axis or y-axis, the maximum stress on Si as a pie-zoresistive material is above, and the average stress on the Si film is around.

The flexible conformal vector hydrophone prepared by heterogeneous integration technology provides ideas for underwater acoustic communication and signal acquisition of biomimetic flexible robotic fish.

We take a state-stewardship view on corporate governance and executive compensation in economies with strong political involvement, where state-appointed managers act as responsible “stewards” rather than “agents” of the state.

We test this view on China and find that Chinese managers are remunerated not for maximizing equity value but for increasing the value of state-owned assets.

Managerial compensation depends on political connections and prestige, and on the firms’ contribution to political goals. These effects were attenuated since the market-oriented governance reform.

Economic reform without reforming the human resources policies at the executive level enables the autocratic state to exert political power on corporate decision making, so as to ensure that firms’ business activities fulfill the state’s political objectives.

As a powerful social elite, the state-steward managers in China have the same interests as the state (the government), namely extracting rents that should adhere to the nation (which stands for the society at large or the collective private citizens).

As China has been a communist country with a single ruling party for decades, the ideas of socialism still have a strong impact on how companies are run. The legitimacy of the elite’s privileged rights over private sectors is central to our question.

Chinese executive compensation stimulates not only the maximization of shareholder value but also the preservation of the state’s interests.

The operation of water environment treatment Public-Private Partnership projects (WETP-PPP) is crucial to the project effectiveness. However, there are often problems in projects that attach importance to construction and neglect operation management, which seriously affect the project operation effect. To ensure the good operation effect of the WETP-PPP, an evolutionary game model of the regulation strategy during the operation period of WETP-PPP is constructed.

An evolutionary game model of regulation is established which considers the government, the project company and the public in water environment treatment Public-Private Partnership projects (WETP-PPP). Five scenarios of equilibriums and the game's evolutionary stable strategies are analyzed, and the corresponding stability conditions are then obtained. Finally, through the simulation, the influence of different factors on the choice of the three-party strategy is analyzed.

First, the key factors that affect the evolution game are the regulation costs and performance rewards of the government, the project company's operation costs and penalties for opportunism and the public supervision costs and rewards. Second, in order to ensure the operation effect, the government needs the performance incentive from the superior government. Third, the public's supervision enthusiasm needs to be mobilized by the government. Last, the penalty strength of speculative operation should be strong enough to play a deterrent role.

The theoretical research in this paper has some limitations. Initially, due to the large number of participants in WETP-PPP, in addition to the government department, the project company and the public studied in this paper, it also involves the consulting industry and financial institutions. In the future, more participants can be added to form four-party interest relationships and conduct four-party evolutionary game research. Second, the operation environment of WETP-PPP is complex and changeable, and various influencing factors are intertwined, the number of parameters involved in this paper is limited, and further detailed research is needed in the future.

Based on the evolutionary game theory, this article discusses the evolution law of the tripartite game behavior of the government department, the project company and the public, which is helpful to clarify the strategy evolution path of the tripartite in the WETP-PPP, and the generation condition and evolution mechanism of the equilibrium strategy of the tripartite game. The key parameters affecting the tripartite strategy selection are analyzed through simulation, which can provide reference for the government department to formulate relevant measures. At the same time, it broadens the application field of evolutionary games and supplements the research on the management mechanism of WETP-PPP during the operation period.

Based on the evolutionary game theory, this paper introduces the supervision behavior of the public, which can provide a new perspective for researchers to conduct relevant research. Secondly, for the regulation during the operation of WETP-PPP, this paper can provide reference for the government department to establish a scientific public supervision system, improve the government supervision mechanism and other relevant measures, which can help promote the public supervision willingness, improve the regulation efficiency of the government and guide the project company to reduce speculation, so as to ensure the effect of water environment management.

This paper focuses on the regulation of WETP-PPP during the operation period to research interactions among the government, the project company and the public. Based on the analysis of the evolutionary game, some suggestions are put forward, such as perfecting the government regulation mechanism, optimizing the reward and punishment system for the project company and broadening the channels of public supervision. The research results of this paper can provide support for the government's regulation of WETP-PPP and ensure the project operation effect.

This purpose of this paper is to design a peg-in-hole controller for a cable-driven serial robot with compliant wrist (CDSR-CW) using cable tensions and joint positions. The peg is connected to the robot link through a CW. It is required that the controller does not rely on any external sensors such as 6-axis wrist force/torque (F/T) sensor, and only the compliance matrix’s estimated value of the CW is known.

First, the peg-in-hole assembly system based on a CDSR-CW is analyzed. Second, a characterization algorithm using micro cable tensions and joint positions to express the elastic F/T at the CW is established. Next, under the premise of only knowing the compliance matrix’s estimate, a peg-in-hole controller based on force/position hybrid control is proposed.

The experiment results show that the plug contact F/T can be tracked well. This verifies the validity and correctness of the characterization algorithm and peg-in-hole controller for CDSR-CWs in this paper.

First, to the authors’ knowledge, there is no relevant work about the peg-in-hole assembly task using a CDSR-CW. Besides, the proposed characterization algorithm for the elastic F/T makes the peg-in-hole controller get rid of the dependence on the F/T sensor, which expands the application scenarios of the peg-in-hole controller. Finally, the controller does not require an accurate compliance matrix, which also increases its applicability.