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This paper aims to provide a precise tracking control scheme for multi-input multi-output “MIMO” nonlinear systems with unknown input time-delay in industrial process.
Abstract
Purpose
This paper aims to provide a precise tracking control scheme for multi-input multi-output “MIMO” nonlinear systems with unknown input time-delay in industrial process.
Design/methodology/approach
The predictive control scheme based on multi-dimensional Taylor network (MTN) model is proposed. First, for the unknown input time-delay, the cross-correlation function is used to identify the input time-delay through just the input and output data. And then, the scheme of predictive control is designed based on the MTN model. It goes as follows: a recursive d-step-ahead MTN predictive model is developed to compensate the influence of time-delay, and the extended Kalman filter (EKF) algorithm is applied for its learning; the multistep predictive objective function is designed, and the optimal controlled output is determined by iterative refinement; and the convergence of MTN predictive model and the stability of closed-loop system are proved.
Findings
Simulation results show that the proposed scheme is of desirable generality and capable of performing the tracking control for MIMO nonlinear systems with unknown input time-delay in industrial process effectively, such as the continuous stirred tank reactor (CSTR) process, which provides a considerably improved performance and effectiveness. The proposed scheme promises strong robustness, low complexity and easy implementation.
Research limitations/implications
For the limitations of proposed scheme, the time-invariant time-delay is only considered in time-delay identification and control schemes. And the CSTR process is only introduced to prove that the proposed scheme can adapt to practical industrial scenario.
Originality/value
The originality of the paper is that the proposed MTN control scheme has good tracking performance, which solves the influence of time-delay, coupling and nonlinearity and the real-time performance for MIMO nonlinear systems with unknown input time-delay.
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This paper provides a quantitative review of the literature on the repercussions of idiosyncratic information on firms’ cost of equity (CoE) capital. In total, I review the…
Abstract
This paper provides a quantitative review of the literature on the repercussions of idiosyncratic information on firms’ cost of equity (CoE) capital. In total, I review the results of 113 unique studies examining the CoE effects of information Quantity, Precision and Asymmetry. My results suggest that the association between firm-specific information and CoE is subject to moderate effects. First, the link between Quantity and CoE is moderated by disclosure types and country-level factors in that firms in comparatively weakly regulated countries tend to enjoy up to four times greater CoE benefits from more expansive disclosure—depending on the type of disclosure—than firms in strongly regulated markets. Second, a negative relationship between Precision and CoE is only significant in studies using non-accrual quality proxies for Precision and risk factor-based (RFB)/valuation model-based (VMB) proxies for CoE. Third, almost all VMB studies confirm the positive association between Asymmetry and CoE, but there is notable variation in the conclusions reached when ex post CoE measurers are used.
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Mohammad Arshad Rahman and Shubham Karnawat
This article is motivated by the lack of flexibility in Bayesian quantile regression for ordinal models where the error follows an asymmetric Laplace (AL) distribution. The…
Abstract
This article is motivated by the lack of flexibility in Bayesian quantile regression for ordinal models where the error follows an asymmetric Laplace (AL) distribution. The inflexibility arises because the skewness of the distribution is completely specified when a quantile is chosen. To overcome this shortcoming, we derive the cumulative distribution function (and the moment-generating function) of the generalized asymmetric Laplace (GAL) distribution – a generalization of AL distribution that separates the skewness from the quantile parameter – and construct a working likelihood for the ordinal quantile model. The resulting framework is termed flexible Bayesian quantile regression for ordinal (FBQROR) models. However, its estimation is not straightforward. We address estimation issues and propose an efficient Markov chain Monte Carlo (MCMC) procedure based on Gibbs sampling and joint Metropolis–Hastings algorithm. The advantages of the proposed model are demonstrated in multiple simulation studies and implemented to analyze public opinion on homeownership as the best long-term investment in the United States following the Great Recession.
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Wei Chen, Zhuzhang Yang, Hang Yan and Ying Zhao
The construction industry is widely recognized as one of the most hazardous sectors in the world. Despite extensive research on safety management, a critical issue remains that…
Abstract
Purpose
The construction industry is widely recognized as one of the most hazardous sectors in the world. Despite extensive research on safety management, a critical issue remains that insufficient attention is devoted to safety practices in rural areas. Notably, accidents frequently occur during the construction of rural self-built houses (RSH) in China. Safety management tends to be overlooked due to the perceived simplicity of the construction process. Furthermore, it is essential to acknowledge that China currently lacks comprehensive laws and regulations governing safety management in RSH construction. This paper aims to analyze the behavior of key stakeholders (including households, workmen, rural village committee and the government) and propose recommendations to mitigate safety risks associated with RSH construction.
Design/methodology/approach
This paper applies evolutionary game theory to analyze the symbiotic evolution among households, workmen and rural village committee, in situations with or without government participation. Additionally, numerical simulation is utilized to examine the outcomes of various strategies implemented by the government.
Findings
Without government participation, households, workmen, and rural village committee tend to prioritize maximizing apparent benefits, often overlooking the potential safety risks. Numerical simulations reveal that while government involvement can guide these parties towards safer decisions, achieving the desired outcomes necessitates the adoption of reasonable and effective strategies. Thus, the government needs to offer targeted subsidies to these stakeholders.
Originality/value
Considering that during the construction phase, stakeholders are the main administrators accountable for safety management. However, there exists insufficient research examining the impact of stakeholder behavior on RSH construction safety. This study aims to analyze the behavior of stakeholders about how to reduce the safety risks in building RSH. Thus, the authors intend to contribute to knowledge in this area by establishing evolutionary game model. Firstly, this study carried out a theoretical by using tripartite evolutionary game to reveal the reasons for the high safety risk during building RSH. Practically, this research points out the important role of households, workmen and rural village committee in improving safety management in rural areas. Besides, some suggestions are proposed to the government about how to reduce construction safety risks in rural areas.
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Haoze Cang, Xiangyan Zeng and Shuli Yan
The effective prediction of crude oil futures prices can provide a reference for relevant enterprises to make production plans and investment decisions. To the nonlinearity, high…
Abstract
Purpose
The effective prediction of crude oil futures prices can provide a reference for relevant enterprises to make production plans and investment decisions. To the nonlinearity, high volatility and uncertainty of the crude oil futures price, a matrixed nonlinear exponential grey Bernoulli model combined with an exponential accumulation generating operator (MNEGBM(1,1)) is proposed in this paper.
Design/methodology/approach
First, the original sequence is processed by the exponential accumulation generating operator to weaken its volatility. The nonlinear grey Bernoulli and exponential function models are combined to fit the preprocessed sequence. Then, the parameters in MNEGBM(1,1) are matrixed, so the ternary interval number sequence can be modeled directly. Marine Predators Algorithm (MPA) is chosen to optimize the nonlinear parameters. Finally, the Cramer rule is used to derive the time recursive formula.
Findings
The predictive effectiveness of the proposed model is verified by comparing it with five comparison models. Crude oil futures prices in Cushing, OK are predicted and analyzed from 2023/07 to 2023/12. The prediction results show it will gradually decrease over the next six months.
Originality/value
Crude oil futures prices are highly volatile in the short term. The use of grey model for short-term prediction is valuable for research. For the data characteristics of crude oil futures price, this study first proposes an improved model for interval number prediction of crude oil futures prices.
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Jinwei Wang, Jie Sun, Guoquan Wang, Li Yang, Yijie Zhang and Alastair M. Morrison
This study aims to examine the empirical linkages among emotional experiences, national identity and behavioural intentions for red tourism in China.
Abstract
Purpose
This study aims to examine the empirical linkages among emotional experiences, national identity and behavioural intentions for red tourism in China.
Design/methodology/approach
Partial least squares structural equation modelling was applied to data from two rounds of surveys of 1,095 on-site visitors to Zunyi and Yan’an, two well-known red tourism cities in China.
Findings
Emotional experiences significantly affect national identity, with positive emotions significantly affecting national identity. Positive emotions also significantly influenced behavioural intentions, national identity positively influenced behavioural intentions and national pride mediated the relationship of “positive emotion → behavioural intentions”. In addition, previous experience played a moderating role in the relationship of “positive emotion → national pride”.
Originality/value
This research produced new insights on red tourism emotional experiences by clarifying its types, connotations and influences. It contributes to a better understanding of national identity antecedents and outcomes in red tourism. Findings revealed the significant role of red tourism in cultivating national identity and provide implications for academic research and practical development of red tourism.
研究目的
本研究旨在考察中国红色旅游者的情绪体验、国家认同和行为意向之间的影响关系及其作用机制。
研究设计/方法论/研究方法
采用偏最小二乘法结构方程模型(PLS-SEM), 对来自中国红色旅游圣地——遵义和延安的1095名现场游客的问卷调查数据进行了统计分析。
研究发现
情绪体验对国家认同会产生显著影响。其中, 积极情感会显著正向影响国家认同。同时, 积极情感也会对行为意向产生显著正向影响。此外, 国家认同对行为意向具有积极影响, 且国家自豪感在“积极情感→行为意图”的影响关系中充当中介作用。最后, 研究还发现旅游经历在“积极情感→国家自豪感”的影响关系中具有显著的调节作用。
独创性/价值
本研究通过阐明红色旅游情绪体验的类型、内涵及其影响关系, 为深入理解红色旅游情绪体验提供了一个全新的视角。同时, 文章还进一步厘清了红色旅游情境中国家认同感的形成前因和影响结果的作用机理。研究结论揭示了红色旅游在培育国家认同感方面的重要价值, 并为红色旅游的学术研究和实践发展提供了重要启示。
Propósito
Esta investigación examinó los vínculos empíricos entre las experiencias emocionales, la identidad nacional y las intenciones de comportamiento para del turismo rojo en China.
Diseño/metodología/enfoque
Se aplicó el análisis de ecuaciones estructurales basado en mínimos cuadrados parciales (PLS - SEM) a los datos recogidos mediante dos rondas de encuestas realizadasa 1.095 visitantes in situ en Zunyi y Yan'an, dos conocidas ciudades de turismo rojo de China.
Hallazgos
Las experiencias emocionales afectan significativamente a la identidad nacional, y las emociones positivas influyen significativamente en la identidad nacional. Las emociones positivas también influyeron significativamente en las intenciones de comportamiento; la identidad nacional influyó positivamente en las intenciones de comportamiento y el orgullo nacional medió la relación “emoción positiva → intenciones de comportamiento”. Además, la experiencia previa desempeñó un papel moderador en la relación “emoción positiva → orgullo nacional”.
Originalidad/valor
Esta investigación aportó nuevos hallazgos sobre las experiencias emocionales del turismo rojo al aclarar sus tipos, connotaciones e influencias. Contribuye a una mejor comprensión de los antecedentes y resultados de la identidad nacional en el turismo rojo. Los resultados de la investigación revelan el importante papel del turismo rojo en el cultivo de la identidad nacional y ofrecen implicaciones para la investigación académica y el desarrollo práctico del turismo rojo.
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Mingwei Li and Juan Chen
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Research limitations/implications
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.
Practical implications
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.
Social implications
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.
Originality/value
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
Purpose
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。
Design/methodology/approach
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。
Findings
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。
Research limitations/implications
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。
Practical implications
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。
Social Implications
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。
Originality/value
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
Propósito
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”.
Diseño/metodología/aproximación
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”.
Resultados
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.
Limitaciones de la investigación/implicaciones
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.
Implicaciones practicas
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.
Implicaciones sociales
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.
Originalidad/valor
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.
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Zhimin Pan, Yu Yan, Yizhou Huang, Wei Jiang, Gao Cheng Ye and Hong Jun Li
The purpose of this paper is to achieve optimal climbing control of the gas-insulated switchgear (GIS) robot, as the authors know that the GIS inspection robot is a kind of…
Abstract
Purpose
The purpose of this paper is to achieve optimal climbing control of the gas-insulated switchgear (GIS) robot, as the authors know that the GIS inspection robot is a kind of artificial intelligent mobile equipment which auxiliary or even substitute human labor drive on the inner wall of the gas-insulated metal enclosed switchgear. The GIS equipment fault inspection and maintenance can be realized through the robot manipulator on the mobile platform and the camera carried on the fuselage, and it is a kind of intelligent equipment for operation. To realize the inspection and operation of the GIS equipment pipeline without blind spots, the robot is required to be able to travel on any wall inside the pipeline, especially the top of the pipeline and both right and left sides of the pipeline, which requires the flexible climbing of the GIS inspection robot. The robot device has a certain adsorption function to ensure that the robot is fully attached to the wall surface. At the same time, the robot manipulator can be used for collision-free obstacle avoidance operation planning in the narrow operation space inside the GIS equipment.
Design/methodology/approach
The above two technologies are the key that the robot completes the GIS equipment inspections. Based on this, this paper focuses on modeling and analysis of the chassis adsorption characteristics for the GIS inspection robot. At the same time, the Denavit Hartenberg (D-H) coordinate model of the robot arm system has been established, and the kinematics forward and inverse solutions of the robot manipulator system have been derived.
Findings
The reachable working space point cloud diagram of the robot manipulator in MATLAB has been obtained based on the kinematics analysis, and the operation trajectory planning of the robot manipulator using the robot toolbox has been obtained. The simulation results show that the robot manipulator system can realize the movement without collision and obstacle avoidance. The space can cover the entire GIS pipeline so as to achieve no blind area operation.
Originality/value
Finally, the GIS inspection robot physical prototype system has been developed through system integration design, and the inspection, maintenance operation experiment has been carried out in the actual GIS equipment. The entire robot system can complete the GIS equipment inspection operation soundly and improve the operation efficiency. The research in this paper has important theoretical significance and practical application value for the optimization design and practical research of the GIS inspection robot system.
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Jesus Diego and Maria J. Montes-Sancho
This paper investigates the role of nexus supplier transparency, which involves the collective information disclosure to the public by second-tier nexus suppliers, as an…
Abstract
Purpose
This paper investigates the role of nexus supplier transparency, which involves the collective information disclosure to the public by second-tier nexus suppliers, as an alternative mechanism for mitigating buyer environmental, social and governance (ESG) risk exposure. We also examine buyer supply network accessibility as a moderating factor that facilitates collecting detailed information and undertaking corrective actions accordingly.
Design/methodology/approach
We collected a sample of 428 focal buyer firms and their supply networks up to third-tier suppliers. Data were obtained from Bloomberg and RepRisk databases. We identified critical nexus suppliers using data envelopment analysis (DEA) and tested hypotheses using regression analysis.
Findings
The results show that the benefits of nexus supplier transparency, such as reducing buyer ESG risk exposure, differ depending on the type of nexus supplier disclosing information and buyer supply network accessibility. Informational nexus supplier transparency was found to be beneficial. However, the results revealed the double-edged sword of monopolistic nexus supplier transparency, which benefits buyers with higher levels of accessibility but increases risk exposure for buyers with lower accessibility.
Originality/value
This study demonstrates that the transparency of critical second-tier suppliers mitigates buyer ESG risk exposure by providing information about lower tiers in the supply network. Challenging the notion of the focal buyer as the main orchestrator of supply chain initiatives, our alternative perspective opens a new avenue for risk management in multi-tier supply chains.
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