The evaluation of network operation and maintenance quality is an important reference for carriers to improve their service.However,the traditional evaluation methods involve so much human participation that it cannot...The evaluation of network operation and maintenance quality is an important reference for carriers to improve their service.However,the traditional evaluation methods involve so much human participation that it cannot cope with the explosive amount of data.Therefore,both the major carriers and researchers are trying to find solutions to evaluate the quality of network operation and maintenance more objectively and accurately.In this paper,we analyze the general process of quality evaluation models for network operation and maintenance.The process has four steps:1)selection of evaluation indicators;2)data process for chosen indicators;3)determination of indicator weights;4)establishment of evaluation models.We further describe the working principle of each step,especially the methods for indicator selection and weight determination.Finally,we review the recently proposed evaluation models and the international stan dards of network operation and maintenance quality evaluation.展开更多
Nowadays, clients require solutions that are efficient during the service life as a whole. In this view, maintenance has functional value and greatly contributes to increasing quality in environments. With reference t...Nowadays, clients require solutions that are efficient during the service life as a whole. In this view, maintenance has functional value and greatly contributes to increasing quality in environments. With reference to maintenance phase and residual value of building products upon dismantling, the present manuscript investigates a set of technological packages of quality and technical value referred to two alternative facade systems available for recovery actions on Italian council buildings--the ETICS （external thermal insulation composite system） and the external cladding system--complying with one thermal-insulation strategy, but different in terms of service life duration. Preservation of technical value and value increases are strictly related to maintenance quality and efficiency. Volume of investments in maintenance is not the only parameter to be considered to assess facade-system-management quality. Time-accurate economic assessment requires the entity to be related to periodical checks on performance quality in the building system and in its parts. Effective technical data to draw up consistent estimates and appraisals are rarely available in literature. With all that stated above, the present manuscript aims at introducing technical data related to drawing up reliable cost estimates and effective appraisals in terms of economics, quality and environmental sustainability. Conclusions will be drawn from the end of the manuscript.展开更多
Purpose–Under the constraints of given passenger service level and coupling travel demand with train departure time,this study optimizes the train operational plan in an urban rail corridor to minimize the numbers of...Purpose–Under the constraints of given passenger service level and coupling travel demand with train departure time,this study optimizes the train operational plan in an urban rail corridor to minimize the numbers of train trips and rolling stocks considering the time-varying demand of urban rail passenger flow.Design/methodology/approach–The authors optimize the train operational plan in a special network layout,i.e.an urban rail corridor with dead-end terminal yard,by decomposing it into two sub-problems:train timetable optimization and rolling stock circulation optimization.As for train timetable optimization,the authors propose a schedule-based passenger flow assignment method,construct the corresponding timetabling optimization model and design the bi-directional coordinated sequential optimization algorithm.For the optimization of rolling stock circulation,the authors construct the corresponding optimization assignment model and adopt the Hungary algorithm for solving the model.Findings–The case study shows that the train operational plan developed by the study’s approach meets requirements on the passenger service quality and reduces the operational cost to the maximum by minimizing the numbers of train trips and rolling stocks.Originality/value–The example verifies the efficiency of the model and algorithm.展开更多
基金supported in part by the Jiangsu Provincial Natural Science Foundation of China under Grant No.BK20171447ZTE Industry-Academia-Research Cooperation FundsNanjing University of Posts and Telecommunications under Grant Nos.NY215045 and NY219084.
文摘The evaluation of network operation and maintenance quality is an important reference for carriers to improve their service.However,the traditional evaluation methods involve so much human participation that it cannot cope with the explosive amount of data.Therefore,both the major carriers and researchers are trying to find solutions to evaluate the quality of network operation and maintenance more objectively and accurately.In this paper,we analyze the general process of quality evaluation models for network operation and maintenance.The process has four steps:1)selection of evaluation indicators;2)data process for chosen indicators;3)determination of indicator weights;4)establishment of evaluation models.We further describe the working principle of each step,especially the methods for indicator selection and weight determination.Finally,we review the recently proposed evaluation models and the international stan dards of network operation and maintenance quality evaluation.
文摘Nowadays, clients require solutions that are efficient during the service life as a whole. In this view, maintenance has functional value and greatly contributes to increasing quality in environments. With reference to maintenance phase and residual value of building products upon dismantling, the present manuscript investigates a set of technological packages of quality and technical value referred to two alternative facade systems available for recovery actions on Italian council buildings--the ETICS （external thermal insulation composite system） and the external cladding system--complying with one thermal-insulation strategy, but different in terms of service life duration. Preservation of technical value and value increases are strictly related to maintenance quality and efficiency. Volume of investments in maintenance is not the only parameter to be considered to assess facade-system-management quality. Time-accurate economic assessment requires the entity to be related to periodical checks on performance quality in the building system and in its parts. Effective technical data to draw up consistent estimates and appraisals are rarely available in literature. With all that stated above, the present manuscript aims at introducing technical data related to drawing up reliable cost estimates and effective appraisals in terms of economics, quality and environmental sustainability. Conclusions will be drawn from the end of the manuscript.
基金funded by the National Natural Science Foundation of China(71701216,71171200).
文摘Purpose–Under the constraints of given passenger service level and coupling travel demand with train departure time,this study optimizes the train operational plan in an urban rail corridor to minimize the numbers of train trips and rolling stocks considering the time-varying demand of urban rail passenger flow.Design/methodology/approach–The authors optimize the train operational plan in a special network layout,i.e.an urban rail corridor with dead-end terminal yard,by decomposing it into two sub-problems:train timetable optimization and rolling stock circulation optimization.As for train timetable optimization,the authors propose a schedule-based passenger flow assignment method,construct the corresponding timetabling optimization model and design the bi-directional coordinated sequential optimization algorithm.For the optimization of rolling stock circulation,the authors construct the corresponding optimization assignment model and adopt the Hungary algorithm for solving the model.Findings–The case study shows that the train operational plan developed by the study’s approach meets requirements on the passenger service quality and reduces the operational cost to the maximum by minimizing the numbers of train trips and rolling stocks.Originality/value–The example verifies the efficiency of the model and algorithm.
