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1 – 10 of 97This study aims to investigate the service performances of a new full-section asphalt concrete waterproof sealing structure (FSACWSS) for the high-speed railway subgrade through…
Abstract
Purpose
This study aims to investigate the service performances of a new full-section asphalt concrete waterproof sealing structure (FSACWSS) for the high-speed railway subgrade through on-site tracking, monitoring and post-construction investigation.
Design/methodology/approach
Based on the working state of the waterproof sealing structure, the main functional characteristics were analyzed, and a kind of roller-compacted high elastic modulus asphalt concrete (HEMAC) was designed and evaluated by several groups of laboratory tests. It is applied to an engineering test section, and the long-term performance monitoring and subgrade dynamic performance testing system were installed to track and monitor working performances of the test section and the adjacent contrast section with fiber-reinforced concrete.
Findings
Results show that both the dynamic performance of the track structure and the subgrade in the test section meet the requirements of the specification limits. The water content in the subgrade of the test section is maintained at 8–18%, which is less affected by the weather. However, the water content in the subgrade bed of the contrast section is 10–35%, which fluctuates significantly with the weather. The heat absorption effect of asphalt concrete in the test section makes the temperature of the subgrade at the shoulder larger than that in the contrastive section. The monitoring value of the subgrade vertical deformation in the test section is slightly larger than that in the contrastive section, but all of them meet the limit requirements. The asphalt concrete in the test section is in good contact with the base, and there are no diseases such as looseness or spalling. Only a number of cracks are found at the joints of the base plates. However, there are more longitudinal and lateral cracks in the contrastive section, which seriously affects the waterproof and sealing effects. Besides, the asphalt concrete is easier to repair, featuring good maintainability.
Originality/value
This research can provide a basis for popularization and application of the asphalt concrete waterproof sealing structure in high-speed railways.
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Keywords
Girish Chandra, Avinash Jain and Sanjay Kumar
The estimation of market value of intangible benefits of afforestation has always been a challenging task, and the contingent valuation method is a popular method used in…
Abstract
Purpose
The estimation of market value of intangible benefits of afforestation has always been a challenging task, and the contingent valuation method is a popular method used in environmental assessment. The NTPC set up a coal-based power plant in Korba, India and planted 1.6 million trees on 19% of the project area.
Design/methodology/approach
The individual's mean and median willingness to pay (WTP) for four intangible benefits, namely, pollution control (PC), improvement in underground water level (IUGWL), soil conservation and remediation (SCR) in addition to total WTP from the afforestation program of NTPC were estimated using a customized procedure for logit model based upon respondent's age, education, occupation, income and bid amount asked to pay. Stratified multistage random sampling has been used to select the respondents.
Findings
The procedure increases the number of respondents who are willing to pay as compared to conventional CVM. The finding of the study shows that the highest WTP was observed for PC (Rs. 462.84 per month per household) followed by SCR and IUGWL, whereas for total WTP it was Rs. 972.60.
Originality/value
The proposed customized procedure and the results thereof would be useful in improving the WTP estimates for other similar studies in order to conserve the environment.
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Xueyan Yang, Changxi Ma, Changfeng Zhu, Bo Qi, Fuquan Pan and Chengming Zhu
For the purpose of reducing the incidence of hazardous materials transport accident, eliminating the potential threats and ensuring their safety, aiming at the shortcomings in the…
Abstract
Purpose
For the purpose of reducing the incidence of hazardous materials transport accident, eliminating the potential threats and ensuring their safety, aiming at the shortcomings in the process of current hazardous materials transportation management, this paper aims to construct the framework of hazardous materials transportation safety management system under the vehicle-infrastructure connected environment.
Design/methodology/approach
The system takes the intelligent connected vehicle as the main supporter, integrating GIS, GPS, eye location, GSM, networks and database technology.
Findings
By analyzing the transportation characteristics of hazardous materials, this system consists of five subsystems, which are vehicle and driver management subsystem, dangerous sources and hazardous materials management subsystem, route analysis and optimization subsystem, early warning and emergency rescue management subsystem, and basic information query subsystem.
Originality/value
Hazardous materials transportation safety management system includes omnibearing real-time monitoring, timely updating of system database, real-time generation and optimization of emergency rescue route. The system can reduce the transportation cost and improve the ability of accident prevention and emergency rescue of hazardous materials.
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Rajesh Kumar, Keshav J. Kumar, Vivek Benegal, Bangalore N. Roopesh and Girikematha S. Ravi
This study aims to examine the effectiveness of an integrated intervention program for alcoholism (IIPA) for improving verbal encoding and memory, visuospatial construction…
Abstract
Purpose
This study aims to examine the effectiveness of an integrated intervention program for alcoholism (IIPA) for improving verbal encoding and memory, visuospatial construction, visual memory and quality of life (QoL) in persons with alcohol dependence.
Design/methodology/approach
The sample comprised treatment-seeking alcohol-dependent persons (n = 50), allotted into two groups: (1) the treatment as usual (TAU) group (n = 25) and (2) the treatment group (n = 25)]. The groups were matched on age (±1 year) and education (±1 year). The TAU group received standard pharmacological treatment, psychotherapeutic sessions on relapse prevention and yoga for 18 days, while the treatment group received IIPA sessions in addition to the usual treatment. Auditory verbal learning test, complex figure test and QoL scale were administered at pre- and post-treatment along with screening measures.
Findings
The two groups were comparable on demographic variables, clinical characteristics and outcome measures at baseline. Pre- to post-treatment changes (gain scores) comparison between the treatment and TAU groups revealed a significant difference in verbal encoding, verbal and visual memory, verbal recognition, visuospatial construction and QoL.
Research limitations/implications
This study suggests that IIPA is effective for improving learning and memory in both modality (verbal and visual) and QoL in persons with alcoholism. The IIPA may help in better treatment recovery.
Practical implications
The IIPA may help in treatment for alcoholism and may enhance treatment efficacy.
Originality/value
IIPA is effective for improving learning and memory in both modalities and QoL in persons with alcohol dependence. The IIPA may help in better treatment recovery.
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The article aims to investigate how washing practices focused on appeasing sceptics of diversity work in for-profit organizations play out in corporate online communication of…
Abstract
Purpose
The article aims to investigate how washing practices focused on appeasing sceptics of diversity work in for-profit organizations play out in corporate online communication of diversity and inclusion efforts, and how these enable communication to a wide audience that includes social equity advocates.
Design/methodology/approach
Online corporate communication data of diversity and inclusion themes were compiled from the websites of eight Swedish-based multinational corporations. The data included content from the companies’ official websites and annual reports and sustainability reports as well as diversity and inclusion-themed blog posts. A thematic analysis was conducted on the website content.
Findings
The study showcases how tensions between conflicting external demands are navigated by keeping the communication open to several interpretations and thereby achieving multivocality. In the studied corporate texts on diversity and inclusion, this is achieved by alternating between elements catering to a business case audience and those that appeal to a social justice audience, with some procedures managing to appease both audiences at the same time.
Originality/value
The article complements previously described forms of washing by introducing an additional type of washing – business case washing – an articulation of the business case rhetoric that characterizes the diversity management discourse. While much has been written about washing to satisfy advocates of social change and equity, washing to appease shareholders and boardroom members, who are focused on profit and economic growth, has received less attention. The article suggests that online corporate communication on diversity and inclusion, by appeasing diverse audiences, can be seen as aspirational talk.
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Jia He, Na Yan, Jian Zhang, Yang Yu and Tao Wang
This paper aims to optimize the charging schedule for battery electric buses (BEBs) to minimize the charging cost considering the time-of-use electricity price.
Abstract
Purpose
This paper aims to optimize the charging schedule for battery electric buses (BEBs) to minimize the charging cost considering the time-of-use electricity price.
Design/methodology/approach
The BEBs charging schedule optimization problem is formulated as a mixed-integer linear programming model. The objective is to minimize the total charging cost of the BEB fleet. The charge decision of each BEB at the end of each trip is to be determined. Two types of constraints are adopted to ensure that the charging schedule meets the operational requirements of the BEB fleet and that the number of charging piles can meet the demand of the charging schedule.
Findings
This paper conducts numerical cases to validate the effect of the proposed model based on the actual timetable and charging data of a bus line. The results show that the total charge cost with the optimized charging schedule is 15.56% lower than the actual total charge cost under given conditions. The results also suggest that increasing the number of charging piles can reduce the charging cost to some extent, which can provide a reference for planning the number of charging piles.
Originality/value
Considering time-of-use electricity price in the BEBs charging schedule will not only reduce the operation cost of electric transit but also make the best use of electricity resources.
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Yang Song, Qi-tao Tian and Ho Kwong Kwan
The purpose of this paper is to examine the effects of servant leadership on employees' promotive voice behavior and prohibitive voice behavior by focusing on the mediating role…
Abstract
Purpose
The purpose of this paper is to examine the effects of servant leadership on employees' promotive voice behavior and prohibitive voice behavior by focusing on the mediating role of job engagement and the moderating role of proactive personality.
Design/methodology/approach
Time-lagged data were collected using a field survey research design. The participants included 216 employees and 23 supervisors in two commercial banks in China.
Findings
Perceived servant leadership was positively related to employees' promotive and prohibitive voice behavior, and these relationships were mediated by enhanced job engagement. In addition, employees' proactive personality amplified the relationship between perceived servant leadership and job engagement, and the mediating effect of job engagement on the relationship between perceived servant leadership and voice behavior.
Research limitations/implications
This study enhances understanding of the mechanisms underlying the servant leadership – voice model by identifying the mediating role of job engagement. The results also demonstrate the moderating role of proactive personality in enhancing the effects of servant leadership. However, the survey design was not longitudinal, which limits the study's ability to confirm causality.
Practical implications
The findings reveal that servant leadership, employees' job engagement, and proactive personality can facilitate employees' promotive and prohibitive voice behavior.
Originality/value
This study addresses the unexplored mediating mechanism of the relationship between servant leadership and voice behavior, and offers new directions for servant leadership and voice research.
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The purpose of this paper is to apply what can be learned from the emergence of nature tourism to understand some current and future trends of tourism.
Abstract
Purpose
The purpose of this paper is to apply what can be learned from the emergence of nature tourism to understand some current and future trends of tourism.
Design/methodology/approach
This study adopted the evolutionary paradigm for investigation.
Findings
The emergence of nature tourism in early medieval China can be attributed to four major factors, including transformation of value orientations, seeking longevity, interest in suburbs and population migration.
Research limitations/implications
Historical studies help understand the current and future trends. When the contributing factors for nature tourism are linked to the contemporary world, it can be found that these factors are still playing a part in shaping tourism trends or patterns in their original or alternative forms. These trends or patterns are worthy of scholarly investigations.
Originality/value
This paper offers a comprehensive understanding of the origins of nature tourism.
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Jinzhi Lu, Yihui Gong, Guoxin Wang and Yan Yan
Model-based systems engineering (MBSE) is an important approach for the transforming process from “document-centered” to “model centered” systems engineering mode in equipment…
Abstract
Purpose
Model-based systems engineering (MBSE) is an important approach for the transforming process from “document-centered” to “model centered” systems engineering mode in equipment development, which can effectively shorten the equipment development cycle and improve product design quality. This paper aims to understand if MBSE enables to support manufacturing and equipment development.
Design/methodology/approach
The paper opted a bibliometric analysis of MBSE in domain of advanced manufacturing from different perspectives such as publication volume, research team, sources and keyword co-occurrence.
Findings
Firstly, the application of MBSE in advanced manufacturing can be roughly divided into three stages. And MBSE has been widely implemented globally and has gradually formed several noteworthy teams. Secondly, this article has identified some high-quality sources, with a large number of publications and citations, the most influential publications focus on the practice or guidance of digital twins and intelligent manufacturing. Thirdly, research can be divided into six categories, including systems engineering, digitalization, intelligent manufacturing, product design, model and architecture and MBSE applications.
Research limitations/implications
Because of the chosen research approach, the visualized network tends to lose certain information such as a few keywords may be inaccurately categorized.
Practical implications
This paper comprehensively study the research status of MBSE in advanced manufacturing and forecasts future research trends, emphasizing the combination of intelligent manufacturing and digitization.
Originality/value
This paper fulfills an identified need to understand the current application status and future development trends of MBSE.
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Xingwen Wu, Zhenxian Zhang, Wubin Cai, Ningrui Yang, Xuesong Jin, Ping Wang, Zefeng Wen, Maoru Chi, Shuling Liang and Yunhua Huang
This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.
Abstract
Purpose
This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.
Design/methodology/approach
Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.
Findings
The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.
Originality/value
The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.
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