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Ultrahigh-speed projectile running in water with the velocity close to the speed of sound usually causes large supercavity. The computation of such transonic cavitating flows is usually difficult, thus high-speed model reflecting the compressibility of both the liquid and the vapor phases should be introduced to model such flow. The purpose of this paper is to achieve a model within an in-house developed solver to simulate the ultrahigh-speed subsonic supercavitating flows.

An improved TAIT equation adjusted by local temperature is adopted as the equation of state (EOS) for the liquid phase, and the Peng-Robinson EOS is used for the vapor phase. An all-speed variable coupling algorithm is used to unify the computations and regulate the convergence at arbitrary Mach number. The ultrahigh-speed (Ma=0.7) supercavitating flows around circular disk are investigated in contrast with the case of low subsonic (Ma=0.007) flow.

The characteristic physical variables are reasonably predicted, and the cavity profiles are compared to be close to the experimental empirical formula. An important conclusion in the compressible cavitating flow theory is verified by the numerical result that, at any specific cavitation number the cavity’s size and the drag coefficient both increase along with the rise of Mach number. On the contrary, it is found as well that the cavity’s slenderness ratio decreases when Mach number goes up. It indicates that the compressibility has different influences on the length and the radius of the supercavity.

A high-speed model reflecting the compressibility of both the liquid and the vapor phases was suggested to model the ultrahigh-speed supercavitating flows around underwater projectiles.

The paper seeks to report data on cigarette smoking, anti‐smoking practices, physicians' receipt of anti‐smoking training, and the association between receipt of the training and anti‐smoking practice among physicians in Wuhan, China.

Participants were selected through the stratified random sampling method. The questionnaires were completed by the sampled physicians and the response rate of the survey was 98.1 percent.

Among the total sample, 11 percent were current smokers. Significantly more male physicians than female physicians were current smokers (31.6 vs 0.9 percent, p<0.001). In total, 41 percent of physicians always or often asked patients about smoking habits, and 61 percent of them often advised patients to quit. Receiving anti‐tobacco training significantly increased the likelihood for physicians to ask patients about smoking (odd ratio=2.55, p<0.001) and to advise patients against smoking (odd ratio=4.05, p<0.001) with and without controlling gender, age, education, type of hospital and medical services specialty.

More effort should be devoted to training for physicians with focus on anti‐smoking practice and smoking cessation counseling in addition to assist physicians themselves to quit smoking.

The findings of this study update the data regarding cigarette smoking among physicians in Wuhan, China, and their practice of anti‐tobacco counseling. It indicates that it is very important to provide the training regarding anti‐smoking counseling among physicians.

This study aims to examine whether, in the opinion of patients selected in 13 hospitals of Hubei province, China, hospitals are smoke free. Patients were also asked whether their physicians had inquired about their smoking status.

Patients were recruited through an intercept method (i.e. stopped by the interviewer while in the hospital); data were collected through interviews, with a response rate of 96.1 percent.

Among the intercepted patients, 48.3 percent reported having seen people smoking in hospitals; 22.3 percent had seen a doctor and/or nurse smoking; 23.8 percent had smelled tobacco in hospitals; 68.4 percent reported having seen “no‐smoking” signs in hospital settings; 42.6 percent reported having been asked about smoking status in their latest visit to a doctor and 23.8 percent reported receiving tobacco cessation counseling. Compared to hospitals in large cities, patients from medium/small city hospitals reported significantly higher levels of cigarette smoking among physicians, and poorer implementation of regulations for a smoking‐free hospital, and less smoking cessation counseling by physicians.

Findings of this study point to the need for greater efforts to be made in promoting a smoke free environment in hospitals, as well as encouraging physicians to provide more smoking cessation counseling to smoking patients, particularly physicians in small and medium hospitals.

The purpose of this paper is to construct a novel delay grey incidence analysis model to analyze drivers and obstacles of university R&D performance.

With respect to the fact that university R&D activities typically experience two stages of knowledge creation and technology transfer, and different drivers and obstacles come into play to affect the conversion of R&D investment to outcomes at each stage, based on the thought of grey incidence analysis and the specific characteristics of science and technology (sci-tech) development, a novel delay grey incidence analysis model is proposed in this paper, and then according to the yearbook statistical data, Chinese university R&D activities are investigated and the drivers and obstacles of university R&D performance are analyzed.

The results show that the R&D full-time staff and R&D funds of basic research are the key drivers of influencing factors, and the sci-tech innovation talents in universities’ R&D institutions and experiment development funds are the restraining factors to improve R&D performance in the stage of knowledge creation; the expenses of R&D achievement application and technology service and the full-time staff of achievement application and technology service are the key drivers and obstacles of influencing the aggregate amount of patent sale respectively.

This research helps policy makers to reflect on their university R&D policies and understand how to enhance the technology transfer rate in China.

The paper succeeds in identifying key drivers and obstacles of affecting university R&D performance in China by examining the input and output incidence at both the knowledge creation and technology transfer stages.

The purpose of this research is to investigate how generalisable the public service motivation (PSM) observed in Western society is to China and to examine the effects of public service motivation on job satisfaction.

Exploratory factor analysis and confirmatory factor analysis techniques are applied to survey data of 191 public servants in China to investigate the generalisability of Western PSM. Using hierarchical regression analysis, the paper examines the effects of the dimensions of PSM on job satisfaction.

The results show that the public service motivation observed in the West exists in China, but the generalisability of the construct is limited. Three of the four dimensions of public service motivation (attraction to public policy making, commitment to the public interest, and self‐sacrifice) exist in China, but the fourth dimension (compassion) is unconfirmed.

The paper is the first to examine the generalisability and instrumentality of PSM as observed in Western society to China. The results indicate that the public service motivation observed in the West also exists in China, but that the generalisability is limited. Public service motivation emerges from the results as a positively significant predictor of job satisfaction in the public sector of China. It enhances the applicability and meaningfulness of the concept of public service motivation across political and cultural environments.

The purpose of this paper is to draw on triadic reciprocal determinism and social exchange theory to examine how “induced-type” and “compulsory-type” union participation influence union commitment and job involvement, and how union participation in the west differs from that in China. It also examines whether the role of both organizational justice and employee participation climate (EPC) functions in the Chinese context.

Cross-sectional data are collected from 694 employees in 46 non-publicly owned enterprises, both Chinese and foreign, in the Pearl River Delta region of China. A multi-level moderated mediation test is used to examine the model of this research.

Union participation is positively related to organizational justice, union commitment and job involvement. In addition, organizational justice acts as the mediator among union participation, union commitment and job involvement. Specifically, the mediating role of organizational justice between union participation and union commitment, and between union participation and job involvement, is stronger in high-EPC contexts than low-EPC contexts.

Instead of examining the impacts of attitudes on union participation, as per most studies in the western context, this research examines the impacts of union participation in the Chinese context on attitudes, including union commitment and job involvement. It also reveals the role of both organizational justice and EPC in the process through which union participation influences union commitment and job involvement.

This study investigates whether and how the service quality of artificial intelligence (AI) chatbots affects customer loyalty to an organization.

Based on the sequential chain model of service quality loyalty, this study first classifies AI chatbot service quality into nine attributes and then develops a research model to explore the internal mechanism of how AI chatbot service quality affects customer loyalty. The analysis of survey data from 459 respondents provided insights into the interrelationships among AI chatbot service quality attributes, perceived value, cognitive and affective trust, satisfaction and customer loyalty.

The results show that AI chatbot service quality positively affects customer loyalty through perceived value, cognitive trust, affective trust and satisfaction.

This study captures the attributes of the service quality of AI chatbots and reveals the significant influence of service quality on customer loyalty. This study develops research on service quality in the information system (IS) field and extends the sequential chain model of quality loyalty to the context of AI services. The findings not only help an organization find a way to improve customers' perceived value, trust, satisfaction and loyalty but also provide guidance in the development, adoption, and post-adoption stages of AI chatbots.

Social networking sites (SNSs) are an indispensable part of people’s daily lives. However, scant literature describes how SNSs affect users’ behaviors, especially consumer behavior in emerging markets. This research aims to fill this literature gap.

Two empirical studies were conducted using different methods. Study 1, a survey, provided correlational evidence. Study 2, a lab experiment, further verified the causal relationship.

From Chinese consumer data, SNS consumption exposure enhances luxury brand consumption, mediated by social comparison motivation and moderated by legitimacy perceptions of SNSs as information outlets.

This research bridges SNSs and luxury brand consumption, two islands among different streams of literature. In addition, the paper illuminates the psychological mechanism through which SNSs affect luxury brand consumption and the boundary condition in which this effect diminishes. Practically, this paper is also instructive for SNSs and luxury brands.

Asteroids have the characteristics of noncooperative, irregular gravity and complex terrain on the surface, which cause difficulties in successful landing for conventional landers. The purpose of this paper is to study the trajectory tracking problem of a multi-node flexible lander with unknown flexible coefficient and space disturbance.

To facilitate the stability analysis, this paper constructs a simplified dynamic model of the multi-node flexible lander. By introducing the nonlinear transformation, a concurrent learning-based adaptive trajectory tracking guidance law is designed to ensure tracking performance, which uses both real-time information and historical data to estimate the parameters without persistent excitation (PE) conditions. A data selection algorithm is developed to enhance the richness of historical data, which can improve the convergence rate of the parameter estimation and the guidance performance.

Finally, Lyapunov stability theory is used to prove that the unknown parameters can converge to their actual value and, meanwhile, the closed-loop system is stable. The effectiveness of the proposed algorithm is further verified through simulations.

This paper provides a new design idea for future asteroid landers, and a trajectory tracking controller based on concurrent learning and preset performance is first proposed.

This paper examined the relationship between firm innovativeness and consumer trust in the sharing economy. In addition, the authors examine the mediating effect of organizational legitimacy and the moderating effect of social worth.

To examine the hypotheses, the authors collected data from 276 users of a sharing platform (Didi) in China to conduct empirical research. The “lavaan” packages in R and SPSS were used to analyze the data and test the proposed hypotheses.

The results reveal that sharing platforms' innovativeness is positively related to consumer trust, and this relationship is mediated by organizational legitimacy. Furthermore, sharing platforms' social worth moderates the relationship between firm innovativeness and organizational legitimacy as well as the indirect effect of firm innovativeness on consumer trust via organizational legitimacy.

This article proposes strategies that enable sharing platforms to increase consumer trust, which can also better promote the development of the sharing economy.

This paper contributes to the literature by focusing on the social attributes of the sharing economy. By building a more detailed model of consumer trust, this paper adds to the knowledge on the influencing mechanism of consumer trust in the sharing economy.