The article intends to find a method to quantify traffic congestion＇s impacts on travelers to help transportation planners and policy decision makers well understand congestion situations. Three new congestion indica...The article intends to find a method to quantify traffic congestion＇s impacts on travelers to help transportation planners and policy decision makers well understand congestion situations. Three new congestion indicators, including transportation environment satisfaction （TES）, travel time satisfaction （TTS）, and traffic congestion frequency and feeling （TCFF）, are defined to estimate urban traffic congestion based on travelers＇ feelings. Data of travelers＇ attitude about congestion and trip information were collected from a survey in Shanghai, China. Based on the survey data, we estimated the value of the three indi- cators. Then, the principal components analysis was used to derive a small number of linear combinations of a set of variables to estimate the whole congestion status. A linear regression model was used to find out the significant variables which impact respondents＇ feelings. Two ordered logit models were used to select significant variables of TES and TTS. Attitudinal factor variables were also used in these models. The results show that attitudinal factor variables and cluster category variables are as important as sociodemographic variables in the models. Using the three congestion indicators, the government can collect travelers＇ feeling about traffic congestion and estimate the transportation policy that might be applied to cope with traffic congestion.展开更多
A bulk power system is conventionally characterized by a complex structure with a large number of components. Each component generally has a different contribution to the transmission congestion(TC) of a system. Thus,...A bulk power system is conventionally characterized by a complex structure with a large number of components. Each component generally has a different contribution to the transmission congestion(TC) of a system. Thus, a TC sharing method that can be used to evaluate the contribution of each component to the system TC and recognize the weak parts from the perspective of TC should be built. This paper presents a transmission congestion tracing(TCT) principle based on the failed component sharing principle and proportional sharing principle and a TCT model using the Monte Carlo simulation method. Case studies on the IEEE Reliability Test System indicate that the proposed method is effective and feasible.展开更多
基金supported by the Key Natural Science Foundation of China:Urban Transportation Planning Theory and Methods under the Information Environment, Grant No. 50738004/E0807
文摘The article intends to find a method to quantify traffic congestion＇s impacts on travelers to help transportation planners and policy decision makers well understand congestion situations. Three new congestion indicators, including transportation environment satisfaction （TES）, travel time satisfaction （TTS）, and traffic congestion frequency and feeling （TCFF）, are defined to estimate urban traffic congestion based on travelers＇ feelings. Data of travelers＇ attitude about congestion and trip information were collected from a survey in Shanghai, China. Based on the survey data, we estimated the value of the three indi- cators. Then, the principal components analysis was used to derive a small number of linear combinations of a set of variables to estimate the whole congestion status. A linear regression model was used to find out the significant variables which impact respondents＇ feelings. Two ordered logit models were used to select significant variables of TES and TTS. Attitudinal factor variables were also used in these models. The results show that attitudinal factor variables and cluster category variables are as important as sociodemographic variables in the models. Using the three congestion indicators, the government can collect travelers＇ feeling about traffic congestion and estimate the transportation policy that might be applied to cope with traffic congestion.
基金supported by National Natural Science Foundation of China(No.51247006)
文摘A bulk power system is conventionally characterized by a complex structure with a large number of components. Each component generally has a different contribution to the transmission congestion(TC) of a system. Thus, a TC sharing method that can be used to evaluate the contribution of each component to the system TC and recognize the weak parts from the perspective of TC should be built. This paper presents a transmission congestion tracing(TCT) principle based on the failed component sharing principle and proportional sharing principle and a TCT model using the Monte Carlo simulation method. Case studies on the IEEE Reliability Test System indicate that the proposed method is effective and feasible.
