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This study aims to present a model and analysis of automotive body outer cover panels (OCPs) assembly systems to predict assembly variation. In the automotive industry, the OCPs assembly process directly influences the quality of the automobile body appearance. However, suitable models to describe variation propagation of OCPs assembly systems remain unknown.

An adaptive state space model for OCPs assembly systems is introduced to accurately express variation propagation, including variation accumulation and transition, where two compliant deviations make impacts on key product characteristics (KPCs) of OCP, and the impacts are accumulated from welding process to threaded connection process. Another new source of variation from threaded connection is included in this model. To quantify the influence of variation from threaded connection on variation propagation, the threaded connection sensitivity matrix is introduced to build up a linear relationship between deviation from threaded connection and output deviation in KPCs. This matrix is solved by homogeneous coordinate transformation. The final deviation of KPCs will be transferred to ensure gaps and flushes between two OCPs, and the transition matrix is considered as a unit matrix to build up the transition relationship between different states.

A practical case on the left side body structure is described, where simulation result of variation propagation reveals the basic rule of variation propagation and the significant effect of variation from threaded connection on variation propagation of OCPs assembly system.

The model can be used to predict assembly variation or potential dimension problems at a preliminary assembly phase. The calculated results of assembly variation guide designers or technicians on tolerance allocation, fixture layout design and process planning.

This paper aims to document and to illustrate highly usable research: a practical framework for realizing the sustainable operations of the high investment, technology-intensive high-speed railways in China. Also, for the first time, we draw a broad, metaphorical relationship between railways within a country to Chinese meridian lines within a human body. These are similar in enabling flows across the country and human body.

Employing Chinese case studies, we attempt to apply methodological procedures involving operational, financial and developmental in realizing the sustainability of high-speed railways. Critical criteria are emphasized for efficiency, financial viability and long-term funding sustained development of high-speed railways in the Chinese context. Policymakers may utilize the illustrative framework in working toward specific recommendations that may be implementable.

Three critical aspects to sustainability are operational, financial solvency and developmental. Our empirical investigations result in the working out of the procedural aspects as well. Based on this three-way classification, we design an evaluative framework for realizing sustainability of high-speed railways. Our insights are based on the social reality of China. Thus, we argue that cash handouts by government are necessary solutions, given the intensive capital investments required of high-speed railways for strongly positive externalities generated. On developmental aspects of sustainability, there should be rational, in-depth studies conducted so as to lead to rational choices of sites. Strong passenger flows coupled with affordability of fares are the twin guarantees of continuing, profitable performances.

This work on sustainability is globally, most highly significant for two reasons. First, railway is one fundamental mean of transportation within China. Thus, the sustainability of railway matters to a majority of the 1.3 billion people. Second, transport volume of China’s railway is the world’s largest. By developing such a comprehensive methodology, we hope to enhance how top management of Chinese Railways may keep the high-speed railways sustainable into the future.

This paper is socially highly significant, especially in the context of what has happened in recent years in China’s railway industry, and may contribute by providing both the regulators and management with an objective methodology in future projects assessment within high-speed railway.

This paper develops an overall framework for enabling management to realize sustainability of high-speed railway within China. The ideas, concepts and methodologies are likely beneficial to top management, regulators and policymakers within the railway transportation, a state monopoly.

Enterprise social media (ESM) are frequently used in enterprises for daily operation. Although many researchers have attempted to understand the antecedents and consequences of ESM use, the integrated model, boundary conditions and mechanism of the impact of ESM use on performance are still unclear. This study fill this research gap by adopting a grounded theory approach to study how ESM use affects employee performance.

Choosing representative cases, the authors collected interview data and analyzed the data using open coding, axial coding and selective coding.

The results showed four main categories including ESM use, work efficiency, emotional maintenance and work performance, as well as 14 sub-categories. This paper also constructs a model of the impact of ESM use on work performance. In addition, results showed that ESM use affects employees' work performance through work efficiency and emotional maintenance, and frequency of use and individual characteristics may moderate this process.

This study’s results contribute to the existing ESM literature by finding the integrated model, boundary conditions and mechanism of the impact of ESM use on performance. The authors also contributed to the social media literature by finding 14 sub-categories and four main categories including ESM use, work efficiency, emotional maintenance and work performance. The conclusion of this paper provides guidance and reference for the use and management of internal social media in enterprises.

This paper aims to disseminate the results of research aiming to identify the prevalence of dysphagia and related clinical factors in nursing home residents.

A cross-sectional descriptive study was developed, including 99 residents in five nursing homes. A sociodemographic questionnaire and the Gugging Swallowing Screen for dysphagia screening were used for data collection.

The prevalence of dysphagia was 59.59%. A significant correlation was found between dysphagia and worse scores for fall risk, pressure ulcer, level of independence for activities of daily living and cognitive functioning.

Results should be interpreted carefully due to sample size and specific country context. A larger sample must be achieved in further research.

Nurses must receive proper training to perform systematic dysphagia screening, and it should be considered, given the high prevalence, the inclusion of professionals specially trained for rehabilitating dysphagic residents in nursing home teams.

The social and economic burden of dysphagia, in addition to all the implications on the person’s quality of life, requires a differentiated focus on this issue by nursing home managers.

Nursing homes have nurses providing health care; however, trained professionals for dysphagia treatment commonly are not. These results highlight the importance of systematic screening for dysphagia in all residents, thus promoting timely intervention to prevent respiratory and nutritional complications.

Employee participation enhances organizational effectiveness. Trust in employees leads to encouragement and acceptance of participation in decision making. There has been recent and growing interest in understanding the basic characteristics of managerial mechanisms within township‐village enterprises (TVEs) in China and how these affect organizational performance. This empirical study investigates how trust influences managers’ decision‐making behavior in the township‐village enterprises in China. The findings of the study suggest that, although TVE managers develop a high level of trust in the dependability, predictability and good faith of their employees, only trust in employee dependability is positively related to participation in the decision‐making process.

The purpose of this paper is to examine borrowing capacity (BC) of government-owned firms and whether real earnings management (REM) activities moderate the sensitivity of firm BC to government ownership.

A simultaneous equation analysis is applied to study 210 Tunisian non-financial firms over the 2001–2014 period.

The empirical results provide substantial evidence indicating that government-owned firms have higher BC and significant REM than other firms; the relationship between government ownership and firm BC is partially moderated by REM activities.

The findings imply that the implicit credit guarantee of government is not necessarily the unique determinant of firm BC and highlight the role of lenders in monitoring discretionary real transactions in government-owned and protected firms. These implications should be taken in to account by public sector policy makers. In particular, the findings predict that the current government accounting reform in Tunisia on the basis of IPSAS will, probably, improve information quality, but it is still insufficient to control real activities in public institutions.

This study extends a growing research stream on the relationship between BC and government ownership by focusing on the moderating effect of REM on this relationship and by considering the endogeneity issue. The findings provide evidence that government-owned firms use REM practices to improve their BC. Examining these practices in developing countries provides an opportunity to evaluate the efficiency of their public sector reforms and their effect on a firm’s performance and financing decisions.

This paper aims to shows the ability of the EDC model with a global reaction mechanism to describe reactions in the Eulerian simulation of a circulating fluidized bed (CFB).

The eddy dissipation concept (EDC) model is embedded in an Eulerian-Eulerian approach to simulate homogeneous reactions.

EDC_G is better than ED_FR in describing chemical reactions. The reaction of CH₄ with O₂ is faster than that of CO with O₂, and NH₃ is more liable to be converted than HCN. The combustion rate is higher than the Boudouard reaction rate of coal particles.N₂O is mainly reduced by carbon, and NO is mainly converted by carbon into N₂ and CO₂.

The EDC model with a global reaction mechanism is embedded in a multi-fluid Eulerian approach to simulate the homogeneous reactions in the coal combustion in a CFB, including combustion of volatile gases, desulfurizing reactions and NO_x reactions.

This paper aims to give the centralized and distributed fusion estimator for nonlinear multi-sensor networked systems with packet loss compensation and correlated noises and give the corresponding square-root cubature Kalman filter.

Based on the Gaussian approximation recursive filter framework, the authors derive the centralized fusion filter and using the projection theorem, the authors derive the centralized fusion smoother. Then, based on the fast batch covariance intersection fusion algorithm, the authors give the corresponding results for distributed fusion estimators.

Designing the fusion estimators for nonlinear multi-sensor networked systems with packet loss compensation and correlated noises is necessary. It is useful for general nonlinear systems.

Throughout the whole study, the main highlights of this paper are as follows: packet loss compensation and correlated noises are considered in nonlinear multi-sensor networked systems. There are no relevant conclusions in the existing literature; centralized and distributed fusion estimators are derived based on the above system; for the posterior covariance with compensation factor and correlated noises, a new square-root factor of the error covariance is derived; and the new square-root factor of the error covariance is used to replace the numerical implementation of the covariance in cubature Kalman filter (CKF), which simplified the problem in calculating the posterior covariance in CKF.

Multiple assembly sequences can increase the flexibility of assembly systems and consequently lead to better performance. The relationship between multiple assembly sequences and their impact on the performance of assembly systems are studied. Based on the concept of operation flexibility, this paper presents a flexibility measure to evaluate each operation sequence. A flexibility‐based criterion is proposed to prioritize each operation, which is then used to guide the assembly scheduling. A simulation study demonstrates that when using the criterion, higher system flexibility is achieved and consequently better performance of the assembly systems is obtained.

The intelligent Central Traffic Control (CTC) system plays a vital role in establishing an intelligent high-speed railway (HSR) system. As the core of HSR transportation command, the intelligent CTC system is a new HSR dispatching command system that integrates the widely used CTC in China with the practical service requirements of intelligent dispatching. This paper aims to propose key technologies and applications for intelligent dispatching command in HSR in China.

This paper first briefly introduces the functions and configuration of the intelligent CTC system. Some new servers, terminals and interfaces are introduced, which are plan adjustment server/terminal, interface for automatic train operation (ATO), interface for Dynamic Monitoring System of Train Control Equipment (DMS), interface for Power Supervisory Control and Data Acquisition (PSCADA), interface for Disaster Monitoring, etc.

The key technologies applied in the intelligent CTC system include automatic adjustment of train operation plans, safety control of train routes and commands, traffic information data platform, integrated simulation of traffic dispatching and ATO function. These technologies have been applied in the Beijing-Zhangjiakou HSR, which commenced operations at the end of 2019. Implementing these key intelligent functions has improved the train dispatching command capacity, ensured the safe operation of intelligent HSR, reduced the labor intensity of dispatching operators and enhanced the intelligence level of China's dispatching system.

This paper provides further challenges and research directions for the intelligent dispatching command of HSR. To achieve the objectives, new measures need to be conducted, including the development of advanced technologies for intelligent dispatching command, coping with new requirements with the development of China's railway signaling system, the integration of traffic dispatching and train control and the application of AI and data-driven modeling and methods.