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The purpose of this paper is to provide a mixture model with modified mass transfer expression for calculating cavitating (two‐phase) flow.

The mass transfer relations are derived based on the mechanics of evaporation and condensation, in which the mass and momentum transfer count for factors such as non‐dissolved gas, turbulence, surface tension, phase‐change rate, etc.

As shown by two calculation examples, the modified model can predict the cavitating flow with high accuracy, agreeing well with experimental results.

The methods described are of value in improving stability in numerical calculations.

The purpose of this paper is to predict pressure pulsation in Kaplan hydraulic turbines.

State of the art numerical simulation techniques are employed to simulate three‐dimensional flows in the whole flow passage of a Kaplan turbine so that pressure pulsations can be computed in both time domain and frequency domain. Numerical results are verified by experiments carried out on the most advanced experimental platform in China.

It is found that the proposed numerical model is a viable tool for prediction of pressure pulsations. The simulation shows that the model turbine and prototype turbine have the same pressure pulsation frequencies and rotating frequencies and the same transmission patterns under similar operation conditions. However, there is no similarity for the amplitude of the pressure pulsation between the model turbine and the prototype turbine. Therefore pressure pulsations in a prototype turbine cannot be obtained by scaling the experimental results of the model turbine using a similarity relationship.

The findings will be very valuable for the design of hydraulic turbines and large‐scale hydraulic power stations.

The proposed numerical method provides a viable tool for hydraulic turbine and power station designers to predict the pressure pulsations in prototype turbines. It is a useful tool to help improve the performance of hydraulic turbines. The findings made in the numerical simulation have been verified by experiments, which is also a valuable reference for hydraulic turbine designers.

Hospital information system (HIS) can be examined as a vital factor for developing the quality of health care and cost managing. There exists abundant literature on HISs, but implementation-based literature of HIS is rare, typically about progressive countries. However, a study that can comprehensively review published articles is scarce. Therefore, this paper aims to examine the systematic and comprehensive study of HIS in developed countries. Together, the benefits and harms relevant to HIS’s different mechanisms have been considered, and the fundamental challenges of them are addressed to design more efficient HIS in the future.

HIS has been used globally for numerous years and is now being used in a wide area. HIS is broadly used in clinical settings. Information technology (IT) and information system have been suggested as a required piece to solve the health-care-related issues. Hence, to improve HIS’s ability, this paper conducted a review method concentratating on research related to HIS until 2019. A total of 21 papers were recognized and examined as principal research for the summary.

The authors found that HIS can help in reduction of medical mistakes, enhancement doctors’ performance and increase in the quality of the care provided. HIS management can be used to provide better health-care services. Therefore, HIS must be sensible and use clear structures. The authors conclude that, generally, with an increase in awareness, acceptability and the need for HIS worldwide, there will be more strategies and approaches available.

First, this paper provides an outline of the status of HIS. Second, it identifies some distinct research gaps that could be worth studying. Some flawless work may be removed because of applying some filters to select the original articles. Surveying all the papers on the topic of HIS is impossible, too.

Design and sustainability of HIS is still a big issue for most developing countries, despite its wide usage in the developed countries. The technology is changing rapidly, so the field should be reviewed regularly. This paper suggests a suitable framework that will guide HIS in the local conditions of developing countries.

The government will be assisted by the suggested solving ways in its performance and design of electronic health-care projects.

The study brings the viewpoints on the state of HIS mechanisms in developing countries. The paper’s results can offer visions into future research requirements. By providing comparative information and analyzing the current growths in this area, this study will support researchers and professionals to understand the progress in HIS mechanisms better.

The authors study the effects of altruism and intention for succession on family firm's reputation risk-taking behaviors in Chinese publicly listed companies.

The authors use earnings management as a proxy for reputation risk in family firms, and hand-collected relationship between family members to measure the closeness of incumbent family members and their potential successors as a proxy for the altruistic degree.

Results show that, in developing countries like China, familial altruism in family firms with succession plans, which does not reduce the practice of earnings management, should be considered by practitioners while detecting it.

The hand collected data are very unique; the authors have focused on the relationship between incumbents and successors and the authors define their closeness by using genes shared between them.

This research proposes an innovative fault-tolerant media content list management technology applied to the smart robot domain.

A fault tolerant Content List Management Unit (CLMU) for real-time streaming systems focusing on smart robot claw machines is proposed to synchronize and manage the hyperlink stored on media servers. The fault-tolerant mechanism is realized by the self-healing method. A media server allows exchanging the hyperlink within the network through the CLMU mechanism.

Internet users can access the current multimedia information, and the multimedia information list can be rearranged appropriately. Furthermore, the service of the proposed multimedia system should be uninterrupted even when the master media server fails. Therefore, one of the slave media servers enables the Content List Service (CLS) of the proposed CLMU and replaces the defunct master media server.

The recovery time is less than 1.5 seconds. The multimedia transmission is not interrupted while any one of the media servers keeps functioning. The proposed method can serve to stabilize the system of media servers in a smart robot domain.

This paper aims to effectively achieve endmembers and relative abundances simultaneously in hyperspectral image unmixing yield. Hyperspectral unmixing, which is an important step before image classification and recognition, is a challenging issue because of the limited resolution of image sensors and the complex diversity of nature. Unmixing can be performed using different methods, such as blind source separation and semi-supervised spectral unmixing. However, these methods have disadvantages such as inaccurate results or the need for the spectral library to be known a priori.

This paper proposes a novel method for hyperspectral unmixing called fuzzy c-means unmixing, which achieves endmembers and relative abundance through repeated iteration analysis at the same time.

Experimental results demonstrate that the proposed method can effectively implement hyperspectral unmixing with high accuracy.

The proposed method present an effective framework for the challenging field of hyperspectral image unmixing.

The purpose of this paper is to discuss the design and fabrication of magnetic couplings to use for vacuum robots. The permanent magnetic coupling (PMC) is appropriate for torque transmission in ultrahigh vacuum and highly clean environments. However, conventional structures of PMC are always unsuitable to use for vacuum robots.

Two types of design scheme for radial magnetic couplings are introduced and compared. The major characteristic of the novel design scheme is that the inner part uses a nonmagnetic mantle to enclose the magnets and yoke, and the outer part uses two end closures to position magnets. The locating groove on the end closure may be manufactured as T‐shape or dovetail shape.

The 3D finite element analysis simulation results and experimental studies have demonstrated that the proposed Design B had a lower contamination rate and a higher transmission efficiency than the Design A.

The limitation of the research to date is that issues of control, path‐planning, and communication have not yet been addressed.

The proposed PMC is successfully applied in vacuum robots which uses combined direct drive techniques and magnetic transmit techniques.

These results suggest that the proposed PMC is suitable for using in vacuum robots.

Internet of things (IoT) is essential in technical, social and economic domains, but there are many challenges that researchers are continuously trying to solve. Traditional resource allocation methods in IoT focused on the optimal resource selection process, but the energy consumption for allocating resources is not considered sufficiently. This paper aims to propose a resource allocation technique aiming at energy and delay reduction in resource allocation. Because of the non-deterministic polynomial-time hard nature of the resource allocation issue and the forest optimization algorithm’s success in complex problems, the authors used this algorithm to allocate resources in IoT.

For the vast majority of IoT applications, energy-efficient communications, sustainable energy supply and reduction of latency have been major goals in resource allocation, making operating systems and applications more efficient. One of the most critical challenges in this field is efficient resource allocation. This paper has provided a new technique to solve the mentioned problem using the forest optimization algorithm. To simulate and analyze the proposed technique, the MATLAB software environment has been used. The results obtained from implementing the proposed method have been compared to the particle swarm optimization (PSO), genetic algorithm (GA) and distance-based algorithm.

Simulation results show that the proper performance of the proposed technique. The proposed method, in terms of “energy” and “delay,” is better than other ones (GA, PSO and distance-based algorithm).

The paper presents a useful method for improving resource allocation methods. The proposed method has higher efficiency compared to the previous methods. The MATLAB-based simulation results have indicated that energy consumption and delay have been improved compared to other algorithms, which causes the high application of this method in practical projects. In the future, the focus will be on resource failure and reducing the service level agreement violation rate concerning the number of resources.

The proposed technique can solve the mentioned problem in the IoT with the best resource utilization, low delay and reduced energy consumption. The proposed forest optimization-based algorithm is a promising technique to help enterprises participate in IoT initiatives and develop their business.

Based on the cognition–affect–conation pattern, this study explores the factors that affect the intention to use facial recognition services (FRS). The study adopts the driving factor perspective to examine how network externalities influence FRS use intention through the mediating role of satisfaction and the barrier factor perspective to analyze how perceived privacy risk affects FRS use intention through the mediating role of privacy cynicism.

The data collected from 478 Chinese FRS users are analyzed via partial least squares-based structural equation modeling (PLS-SEM).

The study produces the following results. (1) FRS use intention is motivated directly by the positive affective factor of satisfaction and the negative affective factor of privacy cynicism. (2) Satisfaction is affected by cognitive factors related to network externalities. Perceived complementarity and perceived compatibility, two indirect network externalities, positively affect satisfaction, whereas perceived critical mass, a direct network externality, does not significantly affect satisfaction. In addition, perceived privacy risk generates privacy cynicism. (3) Resistance to change positively moderates the relationship between privacy cynicism and intention to use FRS.

This study extends knowledge on people's use of FRS by exploring affect- and cognitive-based factors and finding that the affect-based factors (satisfaction and privacy cynicism) play fully mediating roles in the relationship between the cognitive-based factors and use intention. This study also expands the cognitive boundaries of FRS use by exploring the functional condition between affect-based factors and use intention, that is, the moderating role of resistance to use.

Online forums are increasingly deployed as important e‐learning tools for facilitating student learning in classrooms. However, building an online forum does not guarantee participation by students. The purpose of this paper is to advance our knowledge of facilitating student participation in this context by studying the role of communication environment.

The model was tested using data collected from a survey administered in a university in Hong Kong.

Results revealed that psychological safety communication climate influenced the intention of students to continue their participation both directly and indirectly through perceived responsiveness and self‐efficacy.

This study builds on social cognitive theory and extends the existing understanding of participation in e‐learning by highlighting the roles of psychological safety communication climate and perceived responsiveness, two communication environment factors critical to student learning but not yet addressed seriously in the e‐learning context.