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The massive amount of available information and functionality of the Internet makes selective information seeking effortless. This paper aims to understand the selective exposure to information during a health decision-making task.

This study conducted an experiment with a sample of 36 students to examine the influence of prior attitude, perceived threat level and information limit on users’ selective exposure to and recall of coronavirus disease 2019 (COVID-19) vaccination information. Participants were assigned to two conditions with or without an upper limit of the number of articles to be examined, and this study collected the number of articles read, the number of articles included in the report and recall score of the articles after one day of the experiment.

This study found that (1) participants with a negative attitude were more inclined to view attitude-consistent information and recalled attitude-consistent information more accurately, while participants with a positive attitude viewed more balanced information; (2) participants perceiving higher health threat level recalled attitude-consistent information more accurately; and (3) an upper limit on the number of articles to be viewed does not have any impact on selective exposure.

The findings of this paper pinpoint the disparity of influence of positive and negative attitudes on selective exposure to and selective recall of health information, which was not previously recognized.

Vaccination campaigns should focus on reaching people with negative attitudes who are more prone to selective exposure to encourage them to seek more balanced information.

This is the first paper to explore selective exposure to COVID-19 vaccination information. This study found that people with a negative attitude and a higher level of perceived health threat are more prone to selective exposure, which was not found in previous research.

This paper aims to improve the wear resistance of metal rubber microfilaments and the service life. The effect of surface texture by laser processing on the fretting friction properties of metal rubber microfilaments was studied.

The LQL-F20A laser marking machine was used to fabricate a ring groove array with equal spacing and dense arrangement on the surface of metal rubber microfilaments. The test was carried out with a self-made micro-dynamic frictional tester. The topography of the microfilaments was observed by scanning electron microscopy and analyzed.

It has shown that laser surface texturing can improve the wear performance of microfilaments. Under the same experimental conditions, the microfilaments of textured surface has a smaller depth of wear than un-textured specimen. The wear resistance increases with the increase of texture density. The friction coefficient of textured specimen is significantly reduced compared with un-textured specimen, and the surface texture density of microfilaments has little influence on the friction coefficient after stabilization. In the stage of stable fretting wear, the wear depth will be more with the increase of the load.

There is little research on metal rubber microfilaments tribological properties. In this paper, the effect of laser texturing of microfilaments on micro-dynamic friction properties was studied by friction machine to provide a reference for the application of metal rubber in aerospace, medical and other fields.

This study aims to study the thermal identification issue by harvesting both solar energy and atmospheric thermal updraft for a solar-powered unmanned aerial vehicle (SUAV) and its electric energy performance under continuous soaring conditions.

The authors develop a specific dynamic model for SUAVs in both soaring and cruise modes. The support vector machine regression (SVMR) is adopted to estimate the thermal position, and it is combined with feedback control to implement the SUAV soaring in the updraft. Then, the optimal path model is built based on the graph theory considering the existence of several thermals distributed in the environment. The procedure is proposed to estimate the electricity cost of SUAV during flight as well as soaring, and making use of dynamic programming to maximize electric energy.

The simulation results present the integrated control method could allow SUAV to soar with the updraft. In addition, the proposed approach allows the SUAV to fly to the destination using distributed thermals while reducing the electric energy use.

Two simplified dynamic models are constructed for simulation considering there are different flight mode. Besides, the data-driven-based SVMR method is proposed to support SUAV soaring. Furthermore, instead of using length, the energy cost coefficient in optimization problem is set as electric power, which is more suitable for SUAV because its advantage is to transfer the three-dimensional path planning problem into the two-dimensional.

The purpose of this paper is to study the reliability of sintered nano-silver joints on bare copper substrates during high-temperature storage (HTS).

In this study, HTS at 250 °C was carried out to investigate the reliability of nano-silver sintered joints. Combining the evolution of the microstructure and shear strength of the joints, the degradation mechanisms of joints performance were characterized.

The results indicated that the degradation of the shear properties of sintered nano-silver joints on copper substrates was attributed to copper oxidation at the silver/copper interface and interdiffusion of interfacial elements. The joints decreased by approximately 57.4% compared to the original joints after aging for 500 h. In addition, severe coarsening of the silver structure was also an important cause for joints failure during HTS.

This paper provides a comparison of quantitative and mechanistic evaluation of sintered silver joints on bare copper substrates during HTS, which is of great importance in promoting the development of sintered silver technology.

The purpose of this paper is to compare the single-sided packaging structure and double-sided packaging structure of high-power module and study the overall heat dissipation performance and reliability of the module.

In this paper, the single-sided packaging structure and double-sided packaging structure of power module are designed based on Wolfspeed products. This paper is analyzed by finite element method. First, the heat dissipation performance of single-sided packaging structure and double-sided packaging structure is analyzed; second, the deformation and stress of single-sided packaging structure and double-sided packaging structure are compared and analyzed; and finally, the cumulative plastic deformation of single-sided packaging and double-sided packaging structures are compared and analyzed, and the fatigue life of the structure is calculated based on the plastic deformation.

In the heat transfer simulation, under the same power input, the heat dissipation performance of single-sided packaging structure is not as good as that of double-sided packaging structure. Under the reliability simulation of the same temperature cycle standard, the maximum equivalent stress of single-sided packaging structure is lower than that of double-sided packaging structure, but the fatigue life prediction based on plastic strain shows that the fatigue life of double-sided packaging structure is not different from that of single-sided packaging structure.

This paper creatively simulates the thermal characteristics and reliability of single-sided packaging structure and double-sided packaging structure and proves the advantages of double-sided packaging structure compared with single-sided packaging structure from the aspects of heat transfer performance and reliability.

Mobility has wide‐range impacts on the financial management of property issues, such as consumption and investment. In the literature of residential mobility, household life cycle is widely acknowledged as an important concept. An array of household demographic factors such as age has been repeatedly found to be significant in influencing mobility. Many previous researches offer few verifi able hypotheses or propositions and their results are conflicting. Some of them also suffer methodological inadequacies. This paper is an attempt to rectify this situation. There are two important contributions by the current research. One is a methodology that employs multivariate methods, which fills the gap of previous research. The second contribution is the large census dataset of Hong Kong which is rare in previous studies. The research is conducted under the framework of life cycle models with emphasis on economic and demographic variables of households. Demographic determinants are found to be more important in explaining population mobility among rental households while economic factors are more pertinent for owners. This may be explained by the different strategies adopted by renters and owners in satisfying their housing needs. Renters are envisaged to base their mobility decisions more on demographic factors. Owners, on the other hand, tend to view home buying as an investment as well and hence put more emphasis on economic factors. It is hoped that this research can shed more light on the topic of residential mobility by drawing on the experience of a large population residing in a small place, Hong Kong

This paper aims to improve the alignment accuracy of large components in aircraft assembly and an evaluation algorithm, which is based on manufacture accuracy and coordination accuracy, is proposed.

With relative deviations of manufacturing feature points and coordinate feature points, an evaluation function of assembly error is constructed. Then the optimization model of large aircraft digital alignment is established to minimize the synthesis assembly error with tolerance requirements, which consist of three-dimensional (3D) tolerance of manufacturing feature points and relative tolerance between coordination feature points. The non-linear constrained optimization problem is solved by Lagrange multiplier method and quasi-Newton method with its initial value provided by the singular value decomposition method.

The optimized postures of large components are obtained, which makes the tolerance of both manufacturing and coordination requirements be met. Concurrently, the synthesis assembly error is minimized. Compared to the result of the singular value decomposition method, the algorithm is validated in three typical cases with practical data.

The proposed method has been used in several aircraft assembly projects and gained a good effect.

This paper proposes a method to optimize the manufacturing and coordination accuracy with tolerance constraints when the postures of several components are adjusted at the same time. The results of this paper will help to improve the quality of component assemblies.

The goal of this chapter is to respond to the theoretical inquiries by scholars who are interested in how the public–private partnership (PPP) models adapt to China’s context where political power dictates economic strategies. We also want to provide suggestions to policy designers who aim to promote a sustainable investment environment for domestic and international investors. We review the literature that explains the upside and downside of PPP projects in contemporary China. (1) We classify the trajectory of PPP evolution into four phases, i.e., emergence, growth, recession and revival. (2) We note that private companies take a disadvantageous position in the partnership compared with governments and state-owned enterprises because of a lack of specialized legislation, unequal competition between private companies and state-owned enterprises and the opposition from the civic society. (3) We identify political risks as the most influential risks. Political risks also lead to the misallocation of other risks between public and private parties that contributes to the high failure rate of China’s PPP projects. Based on these findings, we recommend governments to draft specialized legislation, stabilize the political environment and provide favourable subsidies to local governments to limit the risks involved in PPP projects. We also advise private enterprises and state-owned enterprises to focus on negotiating over task and risk division with governments when they make decisions to participate in PPP projects. This full review of studies on PPP development in China provides reliable recommendations to scholars, governments and enterprises.

Higher degree of and commitment to voluntary disclosure (VD) and corporate governance (CG) helps contain information asymmetry, leading to lower cost of equity (Ke). This study provides evidence on the nexus among VD, CG, and Ke from a context characterized by extreme political instability.

This study uses all non-bank companies listed with the Palestine Exchange during 2009–2018. The level of VD was estimated by using a checklist of 35 items modified for the context of Palestine. A second checklist with 19 items was used to measure the commitment of the Palestinian companies with CG requirements. Five proxies for Ke were tested: three ex-ante Capital Asset Pricing Model-like proxies and two ex-post realized return proxies.

The findings state that the VD negatively impacted Ke. Interaction effect of CG and VD helps reduce the Ke. As such, for firms with better CG, the increase in VD decreases the Ke more than their standalone effect. For control variables, leverage, size and growth of firms exhibited positive impacts on Ke, whereas quality of auditors found a negative connection.

Managers in similar context, like Palestine, may prefer flexibility of smaller size and adopt conservative growth strategies to cope with adverse events. Firms adopt CG and VD as complementary forces to tackle instability and market expectation.

Studies connecting VD-CG-Ke nexus from similar context are rare. Results of this study forward that emphasis on disclosure and governance practices will help boost the confidence of the investors, reduce the Ke and create an incentive for more investment.