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1 – 10 of over 1000Lots of successful space missions require that the maneuvering spacecraft can reach the target spacecraft. Therefore, research on relative reachable domain (RRD) in target orbit…
Abstract
Purpose
Lots of successful space missions require that the maneuvering spacecraft can reach the target spacecraft. Therefore, research on relative reachable domain (RRD) in target orbit for maneuvering spacecraft is particularly important and is currently a hot-debated topic in the field of aerospace. This paper aims at analyzing and simulating the RRD in target orbit for maneuvering spacecrafts with a single fixed-magnitude impulse and continuous thrust, respectively, to provide a basis for analyzing the feasibility of spacecraft maneuvering missions and improving the design efficiency of spacecraft maneuvering missions.
Design/methodology/approach
Based on the kinematics model of relative motion, RRD in target orbit for maneuvering spacecraft with a single fixed-magnitude impulse can be calculated via analyzing the relationship between orbital elements, position vector and velocity vector of spacecrafts, and relevant studies are introduced to compare simulation results for the same case and validate the method proposed in the paper. With analysis of the dynamic model of relative motion, the calculation of RRD in target orbit for maneuvering spacecraft with continuous thrust can be transformed as the solution of the optimal control problem, and example emulations are carried out to validate the method.
Findings
For the case with a single fixed-magnitude impulse, simulation results show preliminarily that the method is in agreement with the method in Ref. (Wen et al., 2016), which treats the same case and thus is plausibly correct and feasible. For the case with continuous thrust, analysis and simulation results confirm the validity of the proposed method. The methods based on relative motion in this paper can efficiently determining the RRD in target orbit for maneuvering spacecraft.
Originality/value
Both theoretical analyses and simulation results indicate that the method proposed in this paper is comparatively simple but efficient for determine the RRD in target orbit for maneuvering spacecraft swiftly and precisely.
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Yayun Qi, Peng Ao, Maorui Hou and Ailong Zhang
Mountain metro vehicles have unique wheel wear characteristics due to the complex flat and longitudinal lines. With a combination of flat and longitudinal curved tracks, the…
Abstract
Purpose
Mountain metro vehicles have unique wheel wear characteristics due to the complex flat and longitudinal lines. With a combination of flat and longitudinal curved tracks, the traction and braking conditions are more frequent in mountain metro vehicles. This paper aims to analyze the wheel wear characteristics of mountain metro vehicles in complex flat and longitudinal lines.
Design/methodology/approach
A dynamic model of the mountain metro vehicle and a wear model are established to analyze the dynamic and wheel wear characteristics of mountain metro vehicles. The wheel wear law of mountain metro vehicles under complex track conditions is analyzed, and the suppression measure based on variable stiffness rotary arm nodes of mountain metro vehicles is proposed.
Findings
The results showed that the maximum wheel wear depth without considering the ramp track and considering the ramp track are 3.283 mm and 3.717 mm, respectively; the maximum wheel wear depth increases by 13.2%. Wheel wear can be effectively suppressed by the variable stiffness rotary arm model, and the maximum wear depth of the wheel profile is 3.316 mm, which is reduced by 10.79% compared with the constant stiffness model.
Originality/value
A dynamic model of a mountain metro vehicle is established, and the metro vehicle wheel wear under the large ramps under the traction and braking conditions is analyzed, and the metro vehicle wheel wear suppression measure based on variable stiffness rotary arm nodes is proposed.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2024-0247
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Wei Li, Xiaoxuan Yang, Peng Wang, Zefeng Wen and Jian Han
This study aims to investigate the cause of high-order wheel polygonization in a plateau high-speed electric multiple unit (EMU) train.
Abstract
Purpose
This study aims to investigate the cause of high-order wheel polygonization in a plateau high-speed electric multiple unit (EMU) train.
Design/methodology/approach
A series of field tests were conducted to measure the vibration accelerations of the axle box and bogie when the wheels of the EMU train passed through tracks with normal rail roughness after re-profiling. Additionally, the dynamic characteristics of the track, wheelset and bogie were also measured. These measurements provided insights into the mechanisms that lead to wheel polygonization.
Findings
The results of the field tests indicate that wheel polygonal wear in the EMU train primarily exhibits 14–16 and 25–27 harmonic orders. The passing frequencies of wheel polygonization were approximately 283–323 Hz and 505–545 Hz, which closely match the dominated frequencies of axle box and bogie vibrations. These findings suggest that the fixed-frequency vibrations originate from the natural modes of the wheelset and bogie, which can be excited by wheel/rail irregularities.
Originality/value
The study provides novel insights into the mechanisms of high-order wheel polygonization in plateau high-speed EMU trains. Futher, the results indicate that operating the EMU train on mixed lines at variable speeds could potentially mitigate high-order polygonal wear, providing practical value for improving the safety, performance and maintenance efficiency of high-speed EMU trains.
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Heyong Wang, Long Gu and Ming Hong
This paper aims to provide a reference for the development of digital transformation from the perspective of manufacturing process links.
Abstract
Purpose
This paper aims to provide a reference for the development of digital transformation from the perspective of manufacturing process links.
Design/methodology/approach
This paper applies canonical correlation analysis based on digital technology patents in the key links of manufacturing industries (product design, procurement, product manufacturing, warehousing and transportation, and wholesale and retail) and the related indicators of economic benefits of regions in China.
Findings
(1) The degree of digitalization of manufacturing process links is significantly correlated with economic benefits. (2) The improvement of the degree of digitalization in the “product design” link, the “warehousing and transportation” link, the “product manufacturing” link and the “wholesale and retail” link has significant impacts on the economic benefits of manufacturing industry. (3) The digital degree of the “procurement” link has no obvious influence on the economic benefits of manufacturing industry.
Practical implications
The research results can provide reference for the formulation and implementation of micro policies. The strategy of improving the level of digital transformation of key links of manufacturing industry is put forward to better promote both the digital transformation of manufacturing industry and economic development.
Originality/value
This paper innovatively studies the relationship between digitalization of manufacturing process links and economic benefits. The findings can provide theoretical and empirical support for the digital transformation of China's manufacturing industry and high-quality development of economy.
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Huijie Li and Deqing Tan
The purpose of this paper is to study how the government stimulates incineration plants to participate in waste classification management, and how to adjust the subsidy strategy…
Abstract
Purpose
The purpose of this paper is to study how the government stimulates incineration plants to participate in waste classification management, and how to adjust the subsidy strategy for them.
Design/methodology/approach
Considering that the classification behavior of residents will produce herd effect, and waste classification can reduce the disposal cost of incineration plants, the authors constructed a differential game model between the government and waste incineration plants, and analyzed the input strategy of the government and incineration plants when they cooperate in the management of municipal waste classification.
Findings
Increasing the input level of supervision or raising subsidy price, the government can promote incineration plants to increase the input level of incentive. Moreover, from a long-term perspective, increasing the input level of supervision is more effective. Compared with government supervision, the method of incineration plants incentive can more effectively increase the amount of waste disposal. Furthermore, the government supervision and the incineration plants incentive have a positive interaction effect on improving the amount of waste disposal. Increasing the input level of incineration plants incentive or the level of waste-to-energy technology can increase the amount of waste disposal, and from a long-term perspective, increasing the level of R&D investment is more beneficial to increasing the amount of waste disposal.
Originality/value
The results are helpful to improve the investment in the management of waste classification, and also provide a certain theoretical basis for the government's subsidy policy for incineration plants, so as to reduce the financial pressure of the government.
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Yayun Qi, Huanyun Dai, Peng Ao, Xiaolu Cui and Wenhui Mao
Axleboxes are an important structure that connects the wheelset with the bogie frame. Inside axlebox bogies have lower wheelset yaw angle stiffness and better curve-passing…
Abstract
Purpose
Axleboxes are an important structure that connects the wheelset with the bogie frame. Inside axlebox bogies have lower wheelset yaw angle stiffness and better curve-passing performance. The purpose of this paper to study the differences in the wear evolution law and the influencing factors of the two types of metro vehicles.
Design/methodology/approach
This paper established the dynamic model and wear model of both outside axlebox and inside axlebox metro vehicles to research the wheel wear evolution law of the two types of vehicles. The curve passing performance of two vehicles is analyzed. The effect of key parameters on wheel wear is studied, including the lateral distance of the axlebox, the longitudinal stiffness of the rotary arm node, the lateral stiffness of the rotary arm node and the wheel profiles.
Findings
The results showed that the model of inside axlebox metro vehicles improved vehicle safety and curve-passing performance. At the same time, inside axlebox metro vehicles reduce wheel wear of the wheel tread area and wheel flange area. When the S1002 wheel tread profile matched with the vehicle parameters, the wheel wear is minimized.
Originality/value
This paper established a dynamic model for inside axleboxes metro vehicles, then used a wheel wear model to analyze the evolution of wheel wear and the key influencing factors of the inside axleboxes metro vehicles.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2024-0256/
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Narayanage Jayantha Dewasiri, Mawarala Vitharanage Probodika Hanshani, Mananage Shanika Hansini Rathnasiri and Simon Grima
Purpose: This chapter examines the effect of green banking practices (GBPs) on environmental performance (EP), specifically focussing on the Sri Lankan banking industry…
Abstract
Purpose: This chapter examines the effect of green banking practices (GBPs) on environmental performance (EP), specifically focussing on the Sri Lankan banking industry. Additionally, the study explores the mediating impact of green finance in the association between GBPs and the EP of banks listed in the Colombo Stock Exchange in Sri Lanka.
Methodology: The survey included 233 banking employees from Sri Lanka, and data for this study were collected via questionnaires. The formulated hypotheses were tested employing a regression analysis.
Findings: GBPs such as employee, customer, operation, and policy-related practices significantly predicted the banks’ EP. Furthermore, the study highlights that green finance partially mediates the relationship between GBPs and banks’ EP in Sri Lanka.
Implications of the study: The study’s results indicate that banks should prioritise integrating GBPs in their organisations to enhance environmental and overall performance. Moreover, strategically utilising green financing techniques might be a substantial channel for banks to further strengthen their ecological dedication and influence.
Originality: This is the first study to investigate the impact of GBPs on banks’ EP with the mediating effect of green finance in the Sri Lankan context.
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Cemil Akkaş and Aykut Hamit Turan
As our time spent on social networking sites (SNS) is increasing, more people are facing the psychological and mental consequences of SNS use. Given the growing body of research…
Abstract
Purpose
As our time spent on social networking sites (SNS) is increasing, more people are facing the psychological and mental consequences of SNS use. Given the growing body of research on the relationship between social network use and life satisfaction, this study aims to provide an overview of empirical studies through a systematic literature review.
Design/methodology/approach
As a result of the screening process, 43 articles were included in the review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. First, the characteristics of the studies included in the review, such as sample country, data collection method and data analysis method, are presented. Then, the findings on the relationship between SNS use and life satisfaction are outlined.
Findings
Based on the results, it is seen that the relationship between SNS use and life satisfaction varies considerably with the sample and platforms studied. Theoretically, this systematic review provides a comprehensive picture of the relationship between SNS use and life satisfaction and encourages researchers to study the topic further.
Originality/value
There are reviews on the relationship between SNS use and psychological factors such as self-esteem, loneliness or depression. In the reviews, limited variables such as problematic social network use, adolescents’ social network use and social network addiction have been examined instead of general social network use. However, the number of reviews on the relationship between social network use and life satisfaction is quite limited. To the best of the authors’ knowledge, this systematic review is both a comprehensive literature review and one of the first studies to provide a broad perspective on the relationship between social network use and life satisfaction.
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Mahlagha Darvishmotevali, Hasan Evrim Arici and Mehmet Ali Koseoglu
Informed by trait and self-determination theories, the present study aims to extend the knowledge regarding the link between customer satisfaction (CS) and its antecedents…
Abstract
Purpose
Informed by trait and self-determination theories, the present study aims to extend the knowledge regarding the link between customer satisfaction (CS) and its antecedents, including job autonomy (JA), conscientiousness, customer uncertainty (CU) and extra-role customer service (E-RCS) in the hospitality industry.
Design/methodology/approach
A total of 306 frontline employees were selected from the hotels in North Cyprus, Turkey. Psychometric properties, including the validity and reliability of study variables, were assessed in the first step using confirmatory factor analysis. Then, the data were analyzed utilizing machine learning methods, mainly three exploratory data mining techniques, including lasso regression, decision trees and random forest, as well as partial dependence plots to visualize the role of suggested predictors on the outcome variable.
Findings
Data mining analysis shows that employees who can modify their job objectives are better equipped to satisfy customers in uncertain situations (JA8). In addition, the findings reveal that employees who believe they work hard to accomplish their personal and organizational goals (CON7) while also having the freedom to decide how to approach their job (JA1) and choose the procedures to utilize (JA2) are more likely to contribute to CS. In general, CS peaked when JA was high, but conscientiousness was moderate, while CU was low.
Practical implications
This study bridges the gap among various factors at the employee and customer individual, corporate and macro-environmental levels. Hospitality organizations can cultivate a culture of autonomy and independence by promoting open communication and offering growth and development opportunities. This approach enhances conscientious employees’ engagement, leading to exceptional customer service performance, particularly, in uncertain situations.
Originality/value
From the methodology perspective, this work proposes an opportunity for prospective scientists to broaden the trait and self-determination theories research model by relying on the riches of exploratory techniques without the limits imposed by traditional analytical techniques. Further, this study advances the current knowledge about service agility under uncertainty by extending organizational and service management research to consumer behavior literature.
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The research investigates how green bonds and Fintech contribute to advancing sustainable energy adoption in India while addressing the intricate investment risks associated with…
Abstract
Purpose
The research investigates how green bonds and Fintech contribute to advancing sustainable energy adoption in India while addressing the intricate investment risks associated with green initiatives.
Design/methodology/approach
This study employs a stringent approach, conducting an extensive examination of data to analyze the interplay among green bonds, Fintech, and the renewable energy industry in India.
Findings
The study unveils Fintech’s capacity to optimize financing for renewable projects in India by leveraging blockchain technology and digital platforms, enhancing accessibility and investor confidence. Additionally, it underscores the role of green bonds in fostering the development of eco-friendly energy sources.
Originality/value
This research offers novel insights into the dynamic relationship among green bonds, Fintech, and India’s renewable energy sector. It emphasizes the importance of adaptable regulatory frameworks in facilitating sustainability efforts and provides valuable guidance for stakeholders navigating environmental initiatives.
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