Energy saving and emission reduction for railway systems should not only be studied from a technical perspective but should also be focused on management and economics. On the basis of relevant trainscheduling models ...Energy saving and emission reduction for railway systems should not only be studied from a technical perspective but should also be focused on management and economics. On the basis of relevant trainscheduling models for train operation management, in this paper we introduce an extended multi-objective trainscheduling optimization model considering locomotive assignment and segment emission constraints for energy saving. The objective of setting up this model is to reduce the energy and emission cost as well as total passenger- time. The decision variables include continuous variables such as train arrival and departure time, and binary vari- ables such as locomotive assignment and segment occu- pancy. The constraints are concerned with train movement, trip time, headway, and segment emission, etc. To obtain a non-dominated satisfactory solution on these objectives, a fuzzy multi-objective optimization algorithm is employed to solve the model. Finally, a numerical example is performed and used to compare the proposed model with the existing model. The results show that the proposed model can reduce the energy consumption, meet exhausts emission demands effectively by optimal locomotive assignment, and its solution methodology is effective.展开更多
This paper presents and discusses a simulation method for analyzing and evaluating system performance on a rail line from the perspective of speed profile. Dynamic analysis for train motions is introduced, and a discr...This paper presents and discusses a simulation method for analyzing and evaluating system performance on a rail line from the perspective of speed profile. Dynamic analysis for train motions is introduced, and a discrete time-operation graph is proposed to represent the relation between speed profile and energy consumption. Based on them, an analytical model is formulated to provide a quick insight into the system performance. The discrete-time simulation （DTS） method is then implemented to study the system in detail. Compared to the existing simulations, two innovations are included in the DTS： （1） the analytical lookup tables that can simplify the dynamic computation and, （2） the speed profile adjustment process that forecasts and avoids future conflicts based on practical constraints. The numerical results show that the DTS speed profile has advantages over existing methods. Finally, the DTS method is used to analyze and evaluate the system performance of the current timetable on Beijing Yizhuang Metro Line. The results suggest that the current timetable is not robust enough, and thus possible improvements are discussed at both scheduling and operating stages. The proposed method is verified to be effective and reliable for practical uses.展开更多
基金supported by the National Natural Science Foundation of China (No. 71101007)the National High Technology Research and Development Program of China (No. 2011AA110502)State Key Laboratory of Rail Traffic Control and Safety of Beijing Jiaotong University Program (RCS2010ZZ001)
文摘Energy saving and emission reduction for railway systems should not only be studied from a technical perspective but should also be focused on management and economics. On the basis of relevant trainscheduling models for train operation management, in this paper we introduce an extended multi-objective trainscheduling optimization model considering locomotive assignment and segment emission constraints for energy saving. The objective of setting up this model is to reduce the energy and emission cost as well as total passenger- time. The decision variables include continuous variables such as train arrival and departure time, and binary vari- ables such as locomotive assignment and segment occu- pancy. The constraints are concerned with train movement, trip time, headway, and segment emission, etc. To obtain a non-dominated satisfactory solution on these objectives, a fuzzy multi-objective optimization algorithm is employed to solve the model. Finally, a numerical example is performed and used to compare the proposed model with the existing model. The results show that the proposed model can reduce the energy consumption, meet exhausts emission demands effectively by optimal locomotive assignment, and its solution methodology is effective.
文摘This paper presents and discusses a simulation method for analyzing and evaluating system performance on a rail line from the perspective of speed profile. Dynamic analysis for train motions is introduced, and a discrete time-operation graph is proposed to represent the relation between speed profile and energy consumption. Based on them, an analytical model is formulated to provide a quick insight into the system performance. The discrete-time simulation （DTS） method is then implemented to study the system in detail. Compared to the existing simulations, two innovations are included in the DTS： （1） the analytical lookup tables that can simplify the dynamic computation and, （2） the speed profile adjustment process that forecasts and avoids future conflicts based on practical constraints. The numerical results show that the DTS speed profile has advantages over existing methods. Finally, the DTS method is used to analyze and evaluate the system performance of the current timetable on Beijing Yizhuang Metro Line. The results suggest that the current timetable is not robust enough, and thus possible improvements are discussed at both scheduling and operating stages. The proposed method is verified to be effective and reliable for practical uses.
