Considering the development of urban freight transport,this paper presents an operational strategy for freight transport based on the urban metro system.To improve the alignment between service capacity and transport ...Considering the development of urban freight transport,this paper presents an operational strategy for freight transport based on the urban metro system.To improve the alignment between service capacity and transport demand under passenger and freight co-transportation(PFCT),a mixed-integer nonlinear programming model(MINLP)is developed to simultaneously optimize the train timetable(TT)and rolling stock circulation plan(RSCP),with particular consideration of flexible train composition mode and skip-stop strategies.Moreover,by introducing allocation rules for passengers and freight,the tripartite interests of operators,passengers,and freight agents are synergistically considered in the proposed model.To facilitate the model solution,a variable neighborhood search(VNS)algorithm is designed for the generation of high-quality solutions in a reasonable computational time.Finally,based on a simplified example and empirical data from the Beijing Metro Yizhuang Line,several sets of numerical examples are implemented to validate the applicability and effectiveness of the model and the approach.展开更多
The concept ＂panic value＂ （or critical value） was first brought tip by American scholar Lundberg in 1972. It refers to the results of auxiliary examinations that are widely deviating from normal or anticipated res...The concept ＂panic value＂ （or critical value） was first brought tip by American scholar Lundberg in 1972. It refers to the results of auxiliary examinations that are widely deviating from normal or anticipated results. The occurrence of these abnomaal results shows that patients could be in a dangerous situation that their lives might be threatened. If clinicians are able to get the information in time and provide the patients with effective interventions or treatments promptly, lives could be saved. Otherwise, there could be serious consequences and the best opportunities for rescuing the patients might be missing The management of panic value is an important component of medical quality management, as the National Health and Family Planning Commission has clearly defined in the ＂patient safety goals＂ for several consecutive years. In countries such as America, Australia as well as Gennany, the management of panic value has also been greatly emphasized and was been included in various hospital assessments.展开更多
基金supported by the Beijing Natural Science Foundation(9252012)the National Natural Science Foundation of China(72371015,72288101,72431002,and 72161010)Key Laboratory of Railway Industry on Plateau Railway Transportation Intelligent Management and Control(GYYSHZ2301)。
文摘Considering the development of urban freight transport,this paper presents an operational strategy for freight transport based on the urban metro system.To improve the alignment between service capacity and transport demand under passenger and freight co-transportation(PFCT),a mixed-integer nonlinear programming model(MINLP)is developed to simultaneously optimize the train timetable(TT)and rolling stock circulation plan(RSCP),with particular consideration of flexible train composition mode and skip-stop strategies.Moreover,by introducing allocation rules for passengers and freight,the tripartite interests of operators,passengers,and freight agents are synergistically considered in the proposed model.To facilitate the model solution,a variable neighborhood search(VNS)algorithm is designed for the generation of high-quality solutions in a reasonable computational time.Finally,based on a simplified example and empirical data from the Beijing Metro Yizhuang Line,several sets of numerical examples are implemented to validate the applicability and effectiveness of the model and the approach.
文摘The concept ＂panic value＂ （or critical value） was first brought tip by American scholar Lundberg in 1972. It refers to the results of auxiliary examinations that are widely deviating from normal or anticipated results. The occurrence of these abnomaal results shows that patients could be in a dangerous situation that their lives might be threatened. If clinicians are able to get the information in time and provide the patients with effective interventions or treatments promptly, lives could be saved. Otherwise, there could be serious consequences and the best opportunities for rescuing the patients might be missing The management of panic value is an important component of medical quality management, as the National Health and Family Planning Commission has clearly defined in the ＂patient safety goals＂ for several consecutive years. In countries such as America, Australia as well as Gennany, the management of panic value has also been greatly emphasized and was been included in various hospital assessments.
