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The purpose of this paper is to introduce a method for stiffness modeling, identification and updating of collaborative robots (cobots). This method operates in real-time and with high precision and can eliminate the modeling error between the actual stiffness model and the theoretical stiffness model.

To simultaneously ensure the computational efficiency and modeling accuracy of the stiffness model, this method introduces the finite element substructure method (FESM) into the virtual joint method (VJM). The stiffness model of the cobots is built by integrating several 6-degree of freedom virtual joints that represent the elastic deformation of the cobot modules, and the stiffness matrices of these modules can be identified and obtained by the FESM. A model-updating method is proposed to identify stiffness influence coefficients, which can eliminate the modeling error between the actual prototype model and the theoretical finite element model.

The average relative error and the cycle time of the proposed method are approximately 6.14% and 1.31 ms, respectively. Compared with other stiffness modeling methods, this method not only has high modeling accuracy in high dexterity poses but also in low dexterity poses.

A hybrid stiffness modeling method is introduced to integrate the modeling accuracy of the FESM into the VJM. Stiffness influence coefficients are proposed to eliminate the modeling error between the theoretical and actual stiffness models.

The purpose of this paper is to search the optimal arrangement scheme of random motion accuracy of joints for optimal synthesis of pose repeatability which can make robot design more reasonable and reduce the development cost of robots.

In this paper, a mathematical model of pose repeatability, which includes positioning repeatability and orientation repeatability of robots, is established. According to the ISO 9283 standard, an optimal synthesis method of pose repeatability for collaborative robots is introduced, and three optimization objective functions are proposed. The optimization model is solved by using numerical analysis software, and the optimal arrangement scheme of random motion accuracy of joints is obtained which meets the requirements of pose repeatability of robot.

It is found that, in three optimization objective functions, the single-objective evaluation function of maximization of joint motion error is more suitable for optimal synthesis of pose repeatability. In practice, due to the safety factor, the test results of pose repeatability are better than the results of optimal synthesis of pose repeatability.

This method makes robot design more reasonable and reduces the development cost of robots.

This work is the first time to optimize the orientation repeatability of collaborative robots. Because the pose repeatability of most robots is tested by the ISO 9283 standard, so this method which is based on this standard is more suitable for the performance requirements of robot products.

The purpose of this paper is to make an overview of 6,618 publications of Apache Hadoop from 2008 to 2020 in order to provide a conclusive and comprehensive analysis for researchers in this field, as well as a preliminary knowledge of Apache Hadoop for interested researchers.

This paper employs the bibliometric analysis and visual analysis approaches to systematically study and analyze publications about Apache Hadoop in the Web of Science database. This study aims to investigate the topic of Apache Hadoop by means of bibliometric analysis with the aid of visualization applications. Through the bibliometric analysis of the collected documents, this paper analyzes the main statistical characteristics and cooperation networks. Research themes, research hotspots and future development trends are also investigated through the keyword analysis.

The research on Apache Hadoop is still the top priority in the future, and how to improve the performance of Apache Hadoop in the era of big data is one of the research hotspots.

This paper makes a comprehensive analysis of Apache Hadoop with methods of bibliometrics, and it is valuable for researchers can quickly grasp the hot topics in this area.

This paper draws the structural characteristics of the publications in this field and summarizes the research hotspots and trends in this field in recent years, aiming to understand the development status and trends in this field and inspire new ideas for researchers.

The high-speed rail network can lead to the transformation of the tourism industry, as well as the regional economy. In the present study, a reasonable method was developed to assess the contributions of high-speed rail network to the development of tourism and economy in a Chinese region known as the “1 + 8” city tourism circle.

The method proposed here combines not only tourism revenue but also regional economy in a MGM (1, n) gray model, and it studies the tourist and economic output of this tourism circle before and after the high-speed rail network’s construction using an advanced “with and without comparison” method.

By using this method, the accuracy of the prediction of the contribution rate of high-speed rail network is improved. We found that in the “1 + 8” city tourism circle, the high-speed rail network positively contributes to increase of the tourism arrival and tourism revenue. Furthermore, regional economy significantly grows under the impact of the high-speed rail network.

The “1 + 8” city tourism circle is studied as a closed system in this paper, and the authors focus on the economic associations between the cities in the circle by ignoring the impact from outside this circle. This treatment means, simplifies and enables the feasibility of this study, but it virtually leads to the deviation of outcomes between this study and the practical.

For theoretical values, by studying a normal Chinese inland region, this study reconfirmed the positive impact of high-speed railway empirically. In the meantime, this study developed an improved method by introducing gray theory models to “with and without comparison” method to calculate the contribution of high-speed railway to the regional tourism and economy development. Such method simultaneously incorporates the indexes of regional tourism income and regional GDP simultaneously. It is direct and convenient as it can achieve accuracy requirements using only a small amount of data, and it reconciles more with reality by considering the interaction of the outcomes of tourism and economy.

For practical values, using the proposed method, a direct and convenient calculation of the contributions of high-speed railway to many other regions can be achieved if the data of the outcomes of tourism and economy can be obtained. In such a way, the regions that really need high-speed railway to stimulate their development can be distinguished from regions whose high-speed railway is under blind construction. Thus, the government may take actions to reassess some uneconomic high-speed railway projects without discouraging the construction of high-speed railway in other regions. The authors believe that this is important not only for China but also for many other countries with high-speed railway projects.

This study develops a reasonable method of assessing the contribution of high-speed rail to regional tourism and economic development. Using this method, this study confirmed that high-speed rail indeed positively impacts the regional development.

抽象

高速铁路（HSR）网络可以带动旅游业乃至区域经济的转型。本研究构建了一个合理的方法来评估高铁网络对中国 “1+8” 城市旅游圈的旅游产业和区域经济发展的贡献。

本文提出的方法将旅游收入和区域经济的指标结合在一个MGM（1，n）灰色模型中，并采用先进的 “有无比较法” 来研究高铁网建设前后该旅游圈的旅游和经济产出。

利用该方法，可更精准地预测高速铁路网的贡献率。研究发现，在“1+8” 城市旅游圈中，高铁网络对游客到访量和旅游收入的增加起到了积极的促进作用。此外，在高铁网络的影响下，区域经济得到了显著增长。

本文将 “1+8” 城市旅游圈作为一个封闭的系统进行研究，忽略了外部因素的影响，而重点研究旅游圈内城市之间的经济联系。这种处理方法简化了本研究的过程，增加了研究的可行性，但实际上导致了本研究结果与现实存在偏差。

就理论上而言，本文通过对一个典型的中国内陆地区展开研究，从经验上重新确认了高速铁路的积极影响。同时，将灰色理论模型引入到“有无比较法” 中，提出了一种改进方法，用以计算高速铁路对区域旅游业和经济发展的贡献。该方法同时结合了区域旅游收入和GDP指标，十分直接方便，只需要少量数据就可以达到准确的要求；并且由于它考虑到了旅游业和经济的相互作用，更符合实际。

就实用价值而言，只需获得旅游业和经济成果的数据，即可利用该方法直接方便地计算高铁对众多其他地区的贡献。这样一来，就可以将真正需要高铁来刺激发展的地区与盲目建设高铁的地区区分开来。由此，政府可以对一些不经济的高速铁路项目进行重新评估，而不妨碍其他地区的高铁建设。笔者认为，这对中国乃至其他许多国家的高铁项目建设来说是很重要的。

本研究提出了一种合理的方法来评价高铁对区域旅游业和经济发展的贡献。利用这一方法，本研究证实了高铁确实对区域发展产生了积极的影响。

Resumen

La red de ferrocarril de alta velocidad (HSR) puede liderar la transformación de la industria turística, así como la economía regional. En el presente estudio, se ha desarrollado un método para evaluar las contribuciones de la red ferroviaria de alta velocidad, en el desarrollo económico en una región China conocida como el círculo de turismo urbano “1+8”.

El método que se propone combina, no solamente los ingresos por turismo, sino también la economía regional en un modelo MGM (1,n) gris, y estudia la producción turística y económica de este círculo turístico, antes y después de las construcción de la red ferroviaria de alta velocidad utilizando un método “con y sin comparación”.

Usando este método, se mejora la predicción de la tasa de contribución de la red de alta velocidad. Nosotros descubrimos que en el círculo “1+8”, la red ferroviaria de alta velocidad contribuye positivamente al aumento en la llegadas de turistas y los ingresos por turismo. Además, la economía regional, crece significativamente bajo el impacto de esta red.

En este artículo, el círculo de turismo urbano “1+8”, se estudia como un sistema cerrado, se enfoca en la asociación económica entre las ciudades, pero ignorando el impacto desde fuera. Este tratamiento significa simplificar y habilitar la viabilidad de este estudio, pero prácticamente conduce a la desviación de los resultados entre este estudio y la practica.

El valor teórico, estudiando una región normal del interior de China, reconfirma el impacto positivo del ferrocarril de alta velocidad. Mientras tanto, este estudio desarrolla un método mejorado, introduciendo los modelos de “teoría gris” en los métodos “con y sin comparación”, para el calculo de la contribución del ferrocarril de alta velocidad en el desarrollo de la economía regional y turística. Además y simultáneamente, el método incorpora los índices de ingresos del turismo regional y el PIB. Esto es directo y conveniente, ya que puede cumplir con los requisitos de precisión, usando solamente una pequeña cantidad de datos, y concilia más con la realidad considerando la interacción del resultado del turismo y economía.

Para los valores prácticos, usando el modelo propuesto, se puede lograr un cálculo directo y conveniente de las contribuciones del ferrocarril de alta velocidad a muchas otras regiones, y se pueden obtener datos del impacto del turismo y la economía. De esta manera, las regiones que realmente necesiten el ferrocarril de alta velocidad para estimular su desarrollo, se podrán diferenciar de aquellas otras que lo planteen a ciegas. Por lo tanto, los gobiernos deberían tomar acciones para reevaluar algunos proyectos ferroviarios de alta velocidad ineficientes, sin desalentar la construcción de los mismos en otras regiones. Los autores creen que esto no sólo es importante para China, sino también para muchos otros países con proyectos de ferrocarriles de alta velocidad.

Este estudio desarrolla un método razonable de evaluación de la contribución del ferrocarril de alta velocidad, en el desarrollo de la economías regionales y turísticas. Usando este método, este estudio confirma que el ferrocarril de alta velocidad añade impactos positivos en el desarrollo regional.

The primary purpose of this study is to investigate the relationship between leader bottom-line mentality (BLM) and employee innovative behavior, which may be interpreted by employees’ perceived creativity expectations and moderated by employee time orientation.

A multi-wave and multi-source questionnaire survey with 259 paired Chinese employee–leader dyads provided data to test the theoretical model. Hypotheses were tested with Statistical Package for the Social Sciences (SPSS).

Consistent with hypotheses, leader BLM reduces employees’ perceived creativity expectations and thus inhibits employees’ innovative behavior, and this effect is stronger for employees with short-term orientation.

Our findings highlight the negative influences of leader BLM on innovative behavior and the buffering role of employees’ long-term orientation. Organizations may incorporate BLM in leadership promotion and evaluation and provide corresponding training for leaders to overcome BLM. In addition, long-term orientation can be a valuable indicator in employee recruitment and selection.

This study contributes to a new theoretical perspective of the Pygmalion effects for understanding leader BLM’s influence on employee innovative behavior.

Nylon 6 filaments have weak light and heat resistance in terms of stability, which restrict its application in engineering field. The purpose of this paper is to prepare a new photo-stabilization functional nanocomposite inks by using graphene nanosheet as UV light-resisting functional materials incorporated with polyurethane.

Sunlight-resisting functional nylon filaments were produced by the continuous solution dip coating technology, through which the functional inks was coated on the surface of nylon 6 filament. The surface morphology of the coated filaments was characterized by scanning electron microscopy and the graphene/polyurethane nanocomposite inks as the coating agent was confirmed and well dispersed on the fiber’s surface.

Under UV exposure, the strength loss rate of the graphene-modified nylon filaments was less than 50 percent, while that of the control nylon filament was over 85 percent, which indicated that graphene remarkably enhanced the light-resistant property of nylon. Besides, graphene/polyurethane-coated Nylon 6 filaments exhibited reasonable electrical properties and the electrical conductivity could reach 10–4 S/cm.

Graphene inks was first proposed as the UV photo-stabilization in this paper.

The purpose of this study is to explore a sustainable hierarchical framework for the business environment in smart cities. However, this hierarchical framework must consider unnecessary attributes and interrelationships between criteria to capture the difference between smart cities and traditional cities.

Hence, the fuzzy set theory is used for screening unnecessary attributes, the decision-making and trial evaluation laboratory (DEMATEL) is applied to manage the complex interrelationships among the aspects and attributes and interpretive structural modeling (ISM) is used to divide the hierarchy and construct a hierarchical theoretical framework. Ultimately, this research is applied to develop a sustainable hierarchical framework of the business environment in smart cities.

The results show that traditional social problems are still at the core of business environment development in smart cities, new smart opportunities may be discovered, but they are still limited by traditional social factors, the economy is still the main aspect of the business environment and there are still obstacles to solving social problems with smart technologies.

This theoretical hierarchical framework aims to guide smart cities toward sustainability. This study also proposes creating a predictable business environment by improving administrative efficiency, transparency, social mobility and infrastructure services and cultivating new business opportunities with intelligent technology.

The purpose of this paper deals with a capacitated multi-item dynamic lot-sizing problem with the simultaneous sequence-dependent setup scheduling of the parallel resource under complex uncertainty.

An improved chance-constrained method is developed, in which confidence level of uncertain parameters is used to process uncertainty, and based on this, the reliability of the constraints is measured. Then, this study proposes a robust reconstruction method to transform the chance-constrained model into a deterministic model that is easy to solve, in which the robust transformation methods are used to deal with constraints with uncertainty on the right/left. Then, experimental studies using a real-world production data set provided by a gearbox synchronizer factory of an automobile supplier is carried out.

This study has demonstrated the merits of the proposed approach where the inventory of products tends to increase with the increase of confidence level. Due to a larger confidence level may result in a more strict constraint, which means that the decision-maker becomes more conservative, and thus tends to satisfy more external demands at the cost of an increase of production and stocks.

Joint decisions of production lot-sizing and scheduling widely applied in industries can effectively avert the infeasibility of lot-size decisions, caused by capacity of lot-sing alone decision and complex uncertainty such as product demand and production cost. is also challenging.

This study provides more choices for the decision-makers and can also help production planners find bottleneck resources in the production system, thus developing a more feasible and reasonable production plan in a complex uncertain environment.

The aim of this paper is to present a comprehensive analysis of risk management in East Asia from 1998 to 2021 by using bibliometric methods and tools to explore research trends, hotspots, and directions for future research.

The data source for this paper is the Web of Science Core Collection, and 7,154 publications and related information have been derived. We use recognized bibliometric indicators to evaluate publications and visually analyze them through scientific mapping tools (VOS Viewer and CiteSpace).

The analysis results show that China is the most productive and influential country/region. East Asia countries have strong cooperation with each other and also have cooperation with other countries. The study shows that risk management has been involved in various fields such as credit, supply chain, health emergency and disaster especially in the background of COVID-19. We also found that machine learning, especially deep learning, has been playing an increasingly important role in risk management due to its excellent performance.

This paper focuses on studying risk management in East Asia, exploring its publication's fundamental information, citation and cooperation networks, hotspots, and research trends. It provides some reference value for scholars who are interested or further research in this field.

Academic and practitioner attention to the constructs of authentic leadership and work engagement and their implications for organizations has grown dramatically over the past decade. Consideration of the implications of these constructs for high-performance human resource practices (HPHRP) is limited, however. In this monograph, we present a conceptual model that integrates authentic leadership/followership theory with theory and research on HPHRP. Then, we apply this model to systematically consider the implications of skill-enhancing, motivation-enhancing, and opportunity-enhancing HR practices in combination with authentic leadership for authentic followership, follower work engagement, and follower performance. We contend that authentic leadership, through various influences processes, promotes HPHRP, and vice versa, to help foster enhanced work engagement. By cultivating greater work engagement, individuals are motivated to bring their best, most authentic selves to the workplace and are more likely to achieve higher levels of both well-being and performance.