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This paper aims to better understand the dynamic characteristics of an aerostatic slider caused by a gas film, and the impact of a gas film slip on the load capacity, stiffness and dynamic stiffness of the guideway is studied.

In theory, the Navier velocity slip model is introduced for fluid continuous flow equation to calculate the flow state in the micro-state; in experimental techniques, the stiffness experiment of the guideway by digital inductance meter is performed under different loadings, which are used to inspect the simulation results.

The maximum value of bearing stiffness in the condition of considering that the gas slip is larger than that of not considering the gas slip, and the gas film clearance of maximum bearing stiffness in the condition of considering the gas slip is less than that of not considering the gas slip. This is verified by the measurement of the stiffness of the guideway.

This paper mostly studies the influence of the gas slip effects on the performance of the aerostatic guideway, which will make a certain contribution to the guideway stability and the machining precision of the machine tool.

To identify the dynamic feature of the aerostatic slider caused by gas film, an evaluation system by a piezoelectric acceleration sensor is presented in time and frequency domain.

The dynamic pressure fluctuation is evaluated by the wavelet transform, cross correlation analysis and power spectral density (PSD). Wavelet transform is used to process the measured result of the aerostatic slider and the signal is decomposed into high-frequency and low-frequency signal. Correlation analysis method is used to evaluate the impact of the initial gas gap on the fluctuation in time domain.

According to the PSD analysis of the processed signal in the frequency domain, the natural frequency of the aerostatic slider is identified from the measured signal in frequency domain; this method provides a basis for the identification of guideway errors.

The method can also be applied to the error identification of other components of the machine tool.

Wavelet transform is used to process the measured result of the aerostatic slider by acceleration sensor, and the signal is decomposed into high-frequency and low-frequency signal. Correlation analysis method is used to evaluate the impact of the initial gas gap on the fluctuation in time domain. According to the PSD analysis of the processed signal in the frequency domain, the natural frequency of the aerostatic slider is identified from the measured signal in frequency domain; this method provides a basis for the identification of slider errors.

Additive manufacturing offers the ability to produce complex, flexible structures from materials like thermoplastic polyurethane (TPU) for energy-absorption applications. However, selecting optimal structural parameters to achieve desired mechanical responses remains a challenge. This study aims to investigate the influence of key structural characteristics on the energy absorption and dissipation behavior and the deformation process of 3D-printed flexible TPU line-oriented structures.

Samples with varying line orientations and infill densities were fabricated using material extrusion and subjected to quasi-static compression tests. The design of experiments methodology explored the significance of design variables and their interaction effects on energy absorption and dissipation.

The results revealed a statistically significant interaction between infill density and orientation, highlighting their combined influence; however, the effect was less pronounced compared to infill density alone. For low-density structures, changing the orientation from 0°/90° to 45°/−45° and increasing infill density enhanced energy absorption and dissipation, while high-density structures exhibited unique energy absorption behavior influenced by deformation patterns and heterogeneity levels. This study facilitates the prediction of mechanical responses and selection of suitable TPU line-oriented printed parts for energy absorbing applications.

To the best of the authors’ knowledge, the present work have investigated for the first time the energy-related responses of flexible line-oriented TPU structures highlighting the distinction between the low and high density structures.

The Incheon Region has numerous assets that fall within a Pentaport model.' These include the Incheon International Airport, the Port of Incheon, a coastal industrial park, free economic zones, a leisure port, and Songdo new town designed to be the future Silicon Valley of Korea. This paper looks at how Northeast Asia trade flows between China and Korea might be enhanced by application of the Pentaport model in making the Incheon region a North East Asian Hub. It looks also at their trade and logistics systems as well as their water borne commerce. It proposes an integrated transportation system for the Yellow Sea Region being beneficial to the economies of the Northeast Asia. It also stresses that innovative technologies for ships, terminals and cargo handling systems should be introduced to develop a competitive short sea shipping system in the region and cooperation among the regional countries will be essential to achieve the final goal. The potential of methods of container shipping is discussed as it might apply to short sea shipping in the Yellow Sea Region that could greatly facilitate Incheon's situation with respect to the broader region in application of the Pentaport model.

The purpose of this study is to explore factors correlated with police cadets' perceived commitment to the police profession – whether or not personal attitudes and demographic characteristics can make a difference.

The study used two-year longitudinal data collected from a population of 207 Chinese police cadets. Survey research based on pre-designed instruments was employed to collect the data.

The results from panel data analysis found that personal interest in adolescence and attitudes toward styles of policing were significant predictors. Specifically, attitudes toward community policing were positively related to the cadets' commitment to the police profession.

Police occupational commitment is essential since the commitment is closely linked to voluntary retention and organizational effectiveness. However, limited empirical research has been available regarding the factors associated with officers' identification and commitment to the occupation. This study provides insight into police officer training and recruitment and offers suggestions for future research.

In the 21^st Century, a region 's growth and prosperity will depend upon its intermodal transportation infrastructure and its ability to efficiently move goods, materials, and people within the system whether it be from origin to destination; from supplier to customer through the various levels of the supply-chain; or from point to point within the system. Planning for the future focuses on improving a region 's intermodal transportation system efficiencies and infrastructure, its connection to other economies, and on the development of logistics institutions and facilities.

With China 's rapidly developing economy and society, record numbers of new modern facilities such as airports, ports, highways, logistics parks and warehouses are being built. Along with this, companies have made extensive investments in information technologies and software to support the tremendous growth that has taken place in the logistics industry. The development and improvement of China's historic inland water transport system is essential to their continued future growth and prosperity. In Korea, past and present National Governments have emphasized the importance of developing a North East Asian Logistics and Business Hub in their region and have worked on strategies, which include water transport, as part of an important national agenda to that end.

This article looks at how trade flows in the Yangtze and Yellow Sea Regions and between China and South Korea might be enhanced by application of improved shipping methods in marine commerce that will promote economic growth in the region. The application of logistics practices and use of barges is explored for the movement of containers on inland and coastal waterways as well as in short sea shipping which could greatly facilitate the region 's situation with respect to future economic growth.

The purpose of this paper is to explore the task design and assignment of full-text generation on mass Chinese historical archives (CHAs) by crowdsourcing, with special attention paid to how to best divide full-text generation tasks into smaller ones assigned to crowdsourced volunteers and to improve the digitization of mass CHAs and the data-oriented processing of the digital humanities.

This paper starts from the complexities of character recognition of mass CHAs, takes Sheng Xuanhuai archives crowdsourcing project of Shanghai Library as a case study, and makes use of the theories of archival science, including diplomatics of Chinese archival documents, and the historical approach of Chinese archival traditions as the theoretical basis and analysis methods. The results are generated through the comprehensive research.

This paper points out that volunteer tasks of full-text generation include transcription, punctuation, proofreading, metadata description, segmentation, and attribute annotation in digital humanities and provides a metadata element set for volunteers to use in creating or revising metadata descriptions and also provides an attribute tag set. The two sets can be used across the humanities to construct overall observations about texts and the archives of which they are a part. Along these lines, this paper presents significant insights for application in outlining the principles, methods, activities, and procedures of crowdsourced full-text generation for mass CHAs.

This study is the first to explore and identify the effective design and allocation of tasks for crowdsourced volunteers completing full-text generation on CHAs in digital humanities.

The purpose of this study is to examine the effect and duration of supervised field training on police cadets' worldview of police work in China.

The four-wave longitudinal data were collected from graduate students who were pursuing their master's degree in a national Chinese police university from 2016 to 2018. Independent variables including demographic characteristics and knowledge along with experience gained from the internship were used to explain police cadets' attitudes toward police work. Ordinary least square (OLS) regression models were used in the current study.

Findings derived from multiple regression analyses suggest that police cadets' attitudes toward police work are conducive to the “shock” of the real-world experience after three-month field training. However, the effect of the field training on police cadets' attitudes toward police work is temporary, not enduring.

The data for this study were collected from one national police university, and the findings reported here may not be generalized.

Police field training is important for cadets to develop positive view of police work. It provides practical knowledge for police training and socializes cadets before entering into the law enforcement filed, avoiding the financial cost of resignation. However, the influence of field training is temporal. Hence, it is more appropriate for police administrators to arrange police cadets' field training close to their graduation date, the third year of their college education.

This study can be considered as an extension of relevant research on law-enforcement-related field training reported in the United States. However, it goes beyond the existing literature by using longitudinal data to answer a long-overdue question: Does supervised field training change the worldview of cadets concerning police work?

The purpose of this paper is to examine the determinants of juvenile attitudes toward the police (JATP) in Chinese social settings. More specifically, this study borrows from the wisdom of social bond theory and relevant literature developed in the USA to explain juvenile ratings of the police on specific job functions.

The data were collected from a multi-stage cluster sample of 2,704 high school students in a city with a population of 3.8 million located in the southwest region of China. The analysis includes variables derived from social bond theory as well as traditional models commonly employed in US studies, such as demographic background and contact with the police.

The findings suggest that both social bonds and traditional models have their respective utility to explain the variation in juvenile evaluations of the police.

This study expands the scope of the investigation on JATP in China, a distinctively different cultural environment from the USA. More specifically, it explores the utility of the respective explanatory power of the social bond model and traditional models in relation to juveniles’ ratings of the police in China.