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The first purpose of this paper is to design more accurate, efficient and robust gradient smoothing methods (GSMs) for spatial derivative approximations for computational fluid dynamics (CFD) application. The second purpose is to design an adaptive GSM-CFD solver for the compressible turbulent flows, with special focus on the shock-wave boundary layer interactions.

A new integration scheme is proposed for the node-associated GSM to improve the accuracy and robustness of the previous versions. A matrix-based algorithm and corresponding data structures are devised to improve the computational efficiency of GSM. The GSM-CFD solver is coupled with a mixed solution-based adaptive mesher to form a functional adaptive GSM-CFD solver.

The improved GSMs are insensitive to mesh qualities, and can achieve high accuracy on all kinds of hybrid meshes. The adaptive GSM-CFD solver can better capture the shock wave.

The matrix-based GSM and its corresponding data structure for improved GSM, and the development of the adaptive GSM-CFD solver for compressible turbulent flows are newly presented in this paper.

Knowledge protection (KP) is one of the main knowledge management (KM) processes that aim to protect the organization’s knowledge from any inside and outside force leakage. In higher education institutions (HEIs), KP is rarely being discussed and covered in contrast to knowledge sharing (KS) in terms of its determinants. The purpose of this paper is to provide a deep analysis of previous research articles from 1980 to 2019 and examine the associated institutional factors on KP determinants within HEIs as a research objective.

The preferred reporting items for systematic reviews and meta-analysis was a well-established approach for analyzing the systematic literature review methodology. Several articles were published over the past decades collected from 5 different databases, but after the screening, 101 articles were reviewed and only 22 articles were relevant to the research objective.

The findings indicated that KP is under academic research topic in KM and has received minimal attention in HEIs compared to KS, which has been frequently studied in HEIs. The literature categorized KP determinants into four areas: technological, organizational structure, behavioral and ethics and organizational culture. It will open the door for academics to investigate further into the factors, theories and models of KP in general and HEIs from a particular perspective.

As evident from the paper finds, with few pieces of literature covered in this topic, HEIs have to protect the knowledge from any illegal usage or any expert’s knowledge loss after leaving the institutions. This study can help university leaders to understand how the different KP determinants can maximize KP without affecting the KS and develop the KP phenomenon for a strategic fit to enhance their institutions’ safe knowledge usage.

This is the first research of its type which has extensively examined the literature on KP related to HEIs. Also, this paper provides theoretical and practical insights through understanding the determinants that affect KP practices among academic staff.

The factors for higher education institutions’ (HEIs) project management failure have been studied for several years. One of the issues is a lack of tools to combine their knowledge infrastructure capabilities (KIC) with project management (PM) to examine these infrastructures and monitor maturity. There are several project management maturity (PMM) models available. However, there are just a few empirical studies that support the three knowledge infrastructure capabilities and PMM integrations. As a result, the current research aims to suggest a new conceptual model, KIC-knowledge management (KM), and assess a research model that includes the three knowledge infrastructure capabilities as a prerequisite to elevate the PMM.

Partial least squares structural equation modeling (PLS-SEM) is used to evaluate the proposed research model. The study’s hypotheses were also examined using a sample of 352 respondents from PM departments at ten Yemeni public universities.

The study found that if the three key knowledge infrastructure capabilities integrate into the PMs, then it will help HEIs to perform project tasks more effectively and efficiently. Also, it will improve the PM maturity level if all the three capabilities positively effect PMM.

The study findings cannot be generalized to other industries because the collected date were with the Yemeni public universities’ context. Also, the new proposed model can be assessed in various sectors to increase the validity of the model. One more thing, future academics can conduct qualitative research study to validate again the proposed model.

Project managers can develop and improve their organization’s effectiveness and performance by focusing on these findings and using the developed model. Also, the findings of this study can be used as a benchmark for evaluating initiatives and knowledge-based governmental entities.

It is an opportunity for knowledge-based governmental entities particularly and other organizations to elevate most of projects to achieve a supreme level of maturity. Also, this study will assist employees to understand the relationship between KICs and projects within HEIs in Yemen.

This paper is among the first to empirically study the impact of the three knowledge infrastructure capabilities toward PMM. It links between two important domains: KM and PM.

The reasons behind the project management failure of higher education institutions (HEIs) have been researched for the past few years. One of the reasons is the lack of tools to integrate their knowledge process capabilities (KPC) with their project management (PM) to measure maturity by assessing these capabilities. Various project management maturity (PMM) models exist. Yet, there is a limited number of empirical studies that support the four integrations of KPC and PMM. Therefore, this study aims to propose a new heretical model, namely, KPC-knowledge management (KM) and evaluates a research model that includes the four KPC as an antecedent to PMM.

The suggested research model is assessed by using partial least squares structural equation modeling. Furthermore, the study's hypotheses were examined based on a sample of 352 respondents from the project management departments in 10 public universities in Yemen.

Analysis revealed that the derived PMM status could be benchmarked with the project management maturity model. Also, the study found that integrating the KPC into PM enables the institutions to perform critical tasks and value chain activities and enhance the PM maturity level as well. In contrast, if one of the capabilities does not positively impact PMM, it affects the maturity level of the entire project.

The findings are obtained concerning data collected from public universities and represent the Yemeni context, limiting the generalization on a different geographical area. Also, this proposed model can be evaluated in a practical way like conducting a focus group, a set of interviews with specialists, a case study or action research. The qualitative research will help academics to validate our proposal for future research purposes.

The proposed approach may be adapted to the characteristics of organizations involved in projects as external performers (project-based organizations) and not just the HEIs projects. This study provides managers and policymakers with insights into assessing PMM and improving their organizational effectiveness when deciding which KPCs to focus on in the future.

This study contributes to the current PM awareness in Yemen and facilitates its success using the knowledge processes capabilities in Yemen's HEIs. It encourages organizations to take this opportunity to revive the projects and achieve a maximum level of maturity.

This study provides new insights into two domains through the link between knowledge management and PM. To the best of the authors' knowledge, this paper is among the first to empirically study the impact of the four KPC toward PMM. It enriches the theoretical perspective of PM. Also, it contributes to the literature on the success factor of KPC, which can be considered to improve organizational performance.

The purpose of this paper is to propose an agile assistant robot to be used as a mobile partner with two rotational motions and one translational motion. This robot possesses the rolling function and three operating abilities to assistant human beings in the industrial environment.

The main body of the robot is a typical 4-RSR (where R denotes a revolute joint and S denotes a spherical joint) parallel mechanism. The mechanism can reach any position on the ground by two rolling modes (the equivalent Watt linkage rolling mode and the equivalent 6R linkage rolling mode), and the robot can work as a spotlight or a worktable in operating modes at the target location. The mobility, rolling modes, operating modes and kinematics are analyzed.

Based on the results of kinematics of this assistant robot, the upper platform of the 4-RSR rolling mechanism has two rotational motions and one translational motion which can be used in the industry. The proposed concept is verified by experiments on a physical prototype.

This paper also discusses the application to industrial cases where cooperation between workers and robots is required.

The work presented in this paper is a novel exploration to apply parallel mechanisms to the field of assistant rolling robots. It is also a new attempt to use the rolling mechanism in the field of mobile operating robots for industry tasks.

Provides two hybrid methods for the aerodynamic design of cascade profiles, of which the design constraints are the combination of aerodynamic and geometric conditions.

In the first method, the design constrain is composed of the velocity (or pressure) distribution on part of the blade surface and the geometry of the rest part. In the second method, the aerodynamic load distribution, i.e. the pressure difference between the suction and pressure surfaces, and the blade thickness distribution are employed as the design constrain. These constraints, together with all the other boundary conditions, are involved in the stationary conditions of a variational principle. The solution domain, i.e. the blade‐to‐blade passage, is transformed into a square in the image plane, while the blade contour is projected to a straight line; thus, the difficulty caused by the unknown geometry of profile is avoided. Finite element method is employed to produce the calculation code.

Applications show the accuracy and the flexibility of the two methods, which can satisfy the different needs from blade design. Finally, the possibility of combining the hybrid methods with the through‐flow method is discussed, which would develop the present methods to three‐dimensional design of cascades.

The design methods are limited to frictionless flow.

A design software of cascade profiles based on this method has been developed, and will be provided to the engineering users for cascade design.

The hybrid methods developed in this paper can satisfy the demands from different aspects of engineering designs: aerodynamics, strength, manufacture, etc.

Fast growth in China has led to significant improvement in people's living standards and average income. However, it has also brought about a huge rise in inequality. The purpose of this paper is to analyse regional and rural‐urban inequality using a few income and consumption indicators.

Data are collected from official statistical sources for all the Chinese provinces over 1978‐1995. Both parametric and non‐parametric methods are used to study the inequality between regions and between the rural and urban sub‐populations. The parametric approach is to test whether per capita incomes among provinces converged over time. The non‐parametric approach is the calculation and decomposition of the Gini coefficient by population sub‐group and income source.

The results show no evidence of growth convergence in per capita GDP, income and expenditure across provinces, but clear evidence of divergence in per capita rural (and urban) incomes and total expenditures. Three‐quarters of inter‐provincial income inequality are explained by inter‐rural/urban inequality. Inter‐provincial inequality explains more than half of rural inequality and less than half of urban inequality in most years.

This paper uses one of the most complicated datasets for the Chinese regions. It studies inequality using different economic indicators. It considers the different dimensions of inequality in China using two different approaches. The results are important for regional development policies.

The purpose of this paper is to summarize the advances in grey system theory research and various application achievements in science and engineering. At the same time, it commemorates the 40th anniversary of the birth of grey system theory and the 10th anniversary of Grey Systems–Theory and Application.

Firstly, the innovations of theoretical research in grey system theory were summarized and some of the widely recognized new results are briefly described. By searching and combing the research results of grey system theory in China national knowledge infrastructure (CNKI) database and Web of Science by Institute for Scientific Information (ISI), this paper shows the rapid development trend of grey system theory in the past 40 years, and the successful applications of grey system theory in the fields of social sciences, natural sciences and engineering technologies.

More than 227 thousands literature were found by input 10 phrases such as grey system, grey number and sequence operator etc. in CNKI database. After entering the new century, the number of grey system papers included in CNKI database is increasing rapidly. Since 2008, more than 10 thousands papers have been included per year and more than 15 thousands papers have been included per year since 2014. Grey system method and model are widely used in physics, chemistry, biology and other fields of natural science, as well as transportation, electric power, machinery and other fields of engineering technology, and a large number of valuable results have been achieved.

It can be seen that the grey system theory plays an important role in promoting China’s scientific and technological progress, innovation and development and high-level talent training from tens of thousands of literatures marked with important national science and technology projects and a large number of grey system literatures published by China’s double first-class universities and double first-class discipline construction universities.

Both innovations of theoretical research and practical application play important role in the growth of new theory. The innovations of theoretical research provide methods and tools for practical application, which is conducive to improve application efficiency and broaden application fields. A large number of practical applications needs have become the source of theoretical innovation and the solid background for the birth of theoretical innovation achievements.

The purpose of this paper is to summarize the progress in grey system research during 2000-2015, so as to present some important new concepts, models, methods and a new framework of grey system theory.

The new thinking, new models and new methods of grey system theory and their applications are presented in this paper. It includes algorithm rules of grey numbers based on the “kernel” and the degree of greyness of grey numbers, the concept of general grey numbers, the synthesis axiom of degree of greyness of grey numbers and their operations; the general form of buffer operators of grey sequence operators; the four basic models of grey model GM(1,1), such as even GM, original difference GM, even difference GM, discrete GM and the suitable sequence type of each basic model, and suitable range of most used grey forecasting models; the similarity degree of grey incidences, the closeness degree of grey incidences and the three-dimensional absolute degree of grey incidence of grey incidence analysis models; the grey cluster model based on center-point and end-point mixed triangular whitenization functions; the multi-attribute intelligent grey target decision model, the two stages decision model with grey synthetic measure of grey decision models; grey game models, grey input-output models of grey combined models; and the problems of robust stability for grey stochastic time-delay systems of neutral type, distributed-delay type and neutral distributed-delay type of grey control, etc. And the new framework of grey system theory is given as well.

The problems which remain for further studying are discussed at the end of each section. The reader could know the general picture of research and developing trend of grey system theory from this paper.

A lot of successful practical applications of the new models to solve various problems have been found in many different areas of natural science, social science and engineering, including spaceflight, civil aviation, information, metallurgy, machinery, petroleum, chemical industry, electrical power, electronics, light industries, energy resources, transportation, medicine, health, agriculture, forestry, geography, hydrology, seismology, meteorology, environment protection, architecture, behavioral science, management science, law, education, military science, etc. These practical applications have brought forward definite and noticeable social and economic benefits. It demonstrates a wide range of applicability of grey system theory, especially in the situation where the available information is incomplete and the collected data are inaccurate.

The reader is given a general picture of grey systems theory as a new model system and a new framework for studying problems where partial information is known; especially for uncertain systems with few data points and poor information. The problems remaining for further studying are identified at the end of each section.

Employee silence is a pervasive workplace phenomenon that can cause severe economic losses to service organizations. Drawing on conservation of resource theory, the present research aims to investigate interpersonal antecedents of employee silence, specifically workplace ostracism while considering the moderating role of negative reciprocity beliefs (NRBs).

Two-wave data collected from 355 employees working in service organizations in Pakistan supported the theorized model. The study used SmartPLS (v 3.2.7) to examine the measurement model and the structural model.

As projected, the authors found that workplace ostracism was positively related to acquiescence silence and defensive silence, but not related to prosocial silence. Besides, this study’s findings supported two-way interaction involving workplace ostracism and NRB on acquiescence silence and defensive silence, but not on prosocial silence. In particular, the presence of high NRB makes the adverse effects of workplace ostracism even worse.

This study explores the boundary conditions under which employee silence is more likely or less likely to occur. This just makes the current research all the more salient that why and when ostracized employees resort to remain silent in the workplace.