Now the researches concerning integral bus mainly focused on design and analysis of overall mechanical property of bus body, and paid little attention to characteristic of local structures, such as joint, plug welding...Now the researches concerning integral bus mainly focused on design and analysis of overall mechanical property of bus body, and paid little attention to characteristic of local structures, such as joint, plug welding hole, and bolt connection point, etc. So there is much blindness on the design of local connecting structure. Since integral bus body structure cancels large section longitudinal beam, and uses framework made by welding small section bars together as principal part to bear the whole load when the vehicle works, there are many joints receiving high load in the body structure, and local stress concentration can not be avoided. Under such circumstances, by adopting beam-shell mixed model based on super element technique, and selecting a joint commonly used by bus sidewall, the rule of the effect of bar joint’s welding seam spacing on joint’s local mechanical property is investigated in this paper, and the investigating results show that joints have minimum stress concentration with welding seam spacing of 8 mm. To learn whether the above rule is affected by relative bar wall thickness, many groups of bars with different relative bar wall thicknesses are studied experimentally, and the experimental results show that the joints local stress levels vary with different relative bar wall thicknesses, but the rule of the effect of bar joint’s welding seam spacing on joint’s local stress level remains the same. The research is significant for local structure design of bus joint in the future.展开更多
Walking buses are a way to increase physical activity by encouraging people to walk rather than rely on motorized forms of transportation. Several communities support walking school buses as an alternative mode of pup...Walking buses are a way to increase physical activity by encouraging people to walk rather than rely on motorized forms of transportation. Several communities support walking school buses as an alternative mode of pupil transportation to schools. A possible extension of this concept is the introduction of adult walking buses. Given the novelty of the concept, very little is currently known about the public’s perceptions regarding adult walking buses and their potential effectiveness to increase physical activity and decrease obesity among adults. To bridge this gap, this study examined motivations and barriers to participation in an adult walking bus program in Birmingham, Alabama using a comprehensive questionnaire survey. Analysis of over 340 responses revealed a positive reception of the concept among the survey responders. More specifically, 60.1% of the sample reported they would definitely or probably participate in a walking bus program. Results from nested ordinal logistic regression analysis indicate that health benefits are the strongest motivation for willingness to participate in a walking bus program. Sensitivity to environmental issues is also a significant predictor of willingness to participate across models. The most significant barrier to willingness to participate in a walking bus program is limited time. The significance of demographic variables (obesity, race/ ethnicity, and age) as predictors of willingness to participate is reduced once motivations and barriers are controlled. In conclusion, the positive response to the program among our sample is encouraging and suggests that adult walking buses should be explored further as an active alternative transportation option with a potential to improve the health and wellbeing of participants.展开更多
This summer holiday,my older brother and I paid a visit to my grandparents by bus.The bus was crowded,but everyone seemed to be friendly and helpful.We enjoyed beautiful views all the way.At first,we saw one hill afte...This summer holiday,my older brother and I paid a visit to my grandparents by bus.The bus was crowded,but everyone seemed to be friendly and helpful.We enjoyed beautiful views all the way.At first,we saw one hill after another.展开更多
The bus operating characteristics are analyzed at the bus bay using the trajectories depending on the current status of buses. On this basis, a method for calculating the capacity of the bus bay is developed, which co...The bus operating characteristics are analyzed at the bus bay using the trajectories depending on the current status of buses. On this basis, a method for calculating the capacity of the bus bay is developed, which considers the queue probability, the dwell time distribution and the waiting time for a gap in the traffic stream at the curb lane. Then, the distribution model of the dwell time is developed using the survey data of Hangzhou city. And the log-normal distribution shows the best fitting performance. The capacities of the bus bay are computed with the Matlab program under different distribution parameters of the dwell time and different traffic volumes at the curb lane. The results show a large range of traffic capacity as the distribution parameters and traffic volumes change. Finally, the proposed model is validated by measurement and simulation, and the average relative errors between the calculated values and the measured and simulated values are 8.78% and 5.28%, respectively.展开更多
In order to provide important parameters for schedule designing, decision-making bases for transit operation management and references for passengers traveling by bus, bus transit travel time reliability is analyzed a...In order to provide important parameters for schedule designing, decision-making bases for transit operation management and references for passengers traveling by bus, bus transit travel time reliability is analyzed and evaluated based on automatic vehicle location （AVL） data. Based on the statistical analysis of the bus transit travel time, six indices including the coefficient of variance, the width of travel time distribution, the mean commercial speed, the congestion frequency, the planning time index and the buffer time index are proposed. Moreover, a framework for evaluating bus transit travel time reliability is constructed. Finally, a case study on a certain bus route in Suzhou is conducted. Results show that the proposed evaluation index system is simple and intuitive, and it can effectively reflect the efficiency and stability of bus operations. And a distinguishing feature of bus transit travel time reliability is the temporal pattern. It varies across different time periods.展开更多
This paper aims to develop a customer satisfaction model for bus rapid transit （BRT）. Both the socio-economic and travel characteristics of passengers were considered to be independent variables. Changzhou BRT was t...This paper aims to develop a customer satisfaction model for bus rapid transit （BRT）. Both the socio-economic and travel characteristics of passengers were considered to be independent variables. Changzhou BRT was taken as an example and on which on-board surveys were conducted to collect data. Ordinal logistic regression （OLR） was used as the modeling approach. The general OLR-based procedure for modeling customer satisfaction is proposed and based on which the customer satisfaction model of Changzhou BRT is developed. Some important findings are concluded： Waiting sub-journey affects customer satisfaction the most, riding sub- journey comes second and arriving station sub-journey has relatively fewer effects. The availability of shelter and benches at stations imposes heavy influence on customer satisfaction. Passengers＇ socio-economic characteristics have heavy impact on customer satisfaction.展开更多
The common phenomenon of uneven headway in bus service is explored based on the automatic vehicle location （AVL） data of Route 2 in Yichun City of Jiangxi province from 6：00 to 9：00 in the morning. The headway reg...The common phenomenon of uneven headway in bus service is explored based on the automatic vehicle location （AVL） data of Route 2 in Yichun City of Jiangxi province from 6：00 to 9：00 in the morning. The headway regularity of two stages 6： 00--7：00 and 7： 00--9：00 is comparatively analyzed, and it is found that both the traffic conditions and the passenger demand affect headway regularity. A bus arrival model, which assumes that the dwell time of a bus is linear in headway, is built to probe the effect of scheduled headway, and the model is simulated by Matlab. The simulation results reveal that the departure intervals and fluctuations affect headway regularity. Longer intervals and less fluctuation mean higher regularity of headway. And, the fluctuation has a more obvious influence on headway regularity than the interval. Controlling the fluctuations of scheduled headway can effectively raise the regularity of headway and improve the level of public transport service.展开更多
To accurately capture the measurement of bus reliability and evaluate whether the transit system is properly operated an evaluation framework is established to assess the reliability of the transit system from differe...To accurately capture the measurement of bus reliability and evaluate whether the transit system is properly operated an evaluation framework is established to assess the reliability of the transit system from different stratifications including stops routes and network levels.The bus operation data of the Hefei city is analyzed as a case study.Comparison is conducted to show the improvement made by using the advanced method and an example of adding exclusive bus lanes to the existing bus route is provided. The proposed advanced method can avoid the shortcomings of the traditional method.For example the value of the reliability using the traditional coefficient of variation CV is not between 0 and 1 and the value of reliability can decrease with the increase in the transit headway etc. The case study shows that the advanced method can represent the real operation condition of the transit system and can be used to evaluate the transit headway reliability more reasonably.展开更多
基金supported by National Hi-tech Research and Development Program of China (863 Program, Grant No. 2006AA110104)
文摘Now the researches concerning integral bus mainly focused on design and analysis of overall mechanical property of bus body, and paid little attention to characteristic of local structures, such as joint, plug welding hole, and bolt connection point, etc. So there is much blindness on the design of local connecting structure. Since integral bus body structure cancels large section longitudinal beam, and uses framework made by welding small section bars together as principal part to bear the whole load when the vehicle works, there are many joints receiving high load in the body structure, and local stress concentration can not be avoided. Under such circumstances, by adopting beam-shell mixed model based on super element technique, and selecting a joint commonly used by bus sidewall, the rule of the effect of bar joint’s welding seam spacing on joint’s local mechanical property is investigated in this paper, and the investigating results show that joints have minimum stress concentration with welding seam spacing of 8 mm. To learn whether the above rule is affected by relative bar wall thickness, many groups of bars with different relative bar wall thicknesses are studied experimentally, and the experimental results show that the joints local stress levels vary with different relative bar wall thicknesses, but the rule of the effect of bar joint’s welding seam spacing on joint’s local stress level remains the same. The research is significant for local structure design of bus joint in the future.
文摘Walking buses are a way to increase physical activity by encouraging people to walk rather than rely on motorized forms of transportation. Several communities support walking school buses as an alternative mode of pupil transportation to schools. A possible extension of this concept is the introduction of adult walking buses. Given the novelty of the concept, very little is currently known about the public’s perceptions regarding adult walking buses and their potential effectiveness to increase physical activity and decrease obesity among adults. To bridge this gap, this study examined motivations and barriers to participation in an adult walking bus program in Birmingham, Alabama using a comprehensive questionnaire survey. Analysis of over 340 responses revealed a positive reception of the concept among the survey responders. More specifically, 60.1% of the sample reported they would definitely or probably participate in a walking bus program. Results from nested ordinal logistic regression analysis indicate that health benefits are the strongest motivation for willingness to participate in a walking bus program. Sensitivity to environmental issues is also a significant predictor of willingness to participate across models. The most significant barrier to willingness to participate in a walking bus program is limited time. The significance of demographic variables (obesity, race/ ethnicity, and age) as predictors of willingness to participate is reduced once motivations and barriers are controlled. In conclusion, the positive response to the program among our sample is encouraging and suggests that adult walking buses should be explored further as an active alternative transportation option with a potential to improve the health and wellbeing of participants.
文摘This summer holiday,my older brother and I paid a visit to my grandparents by bus.The bus was crowded,but everyone seemed to be friendly and helpful.We enjoyed beautiful views all the way.At first,we saw one hill after another.
基金The National High Technology Research and Development Program of China(863 Program)(No.2011AA110304)
文摘The bus operating characteristics are analyzed at the bus bay using the trajectories depending on the current status of buses. On this basis, a method for calculating the capacity of the bus bay is developed, which considers the queue probability, the dwell time distribution and the waiting time for a gap in the traffic stream at the curb lane. Then, the distribution model of the dwell time is developed using the survey data of Hangzhou city. And the log-normal distribution shows the best fitting performance. The capacities of the bus bay are computed with the Matlab program under different distribution parameters of the dwell time and different traffic volumes at the curb lane. The results show a large range of traffic capacity as the distribution parameters and traffic volumes change. Finally, the proposed model is validated by measurement and simulation, and the average relative errors between the calculated values and the measured and simulated values are 8.78% and 5.28%, respectively.
基金The Soft Science Research Project of Ministry of Housing and Urban-Rural Development of China (No. 2008-k5-14)
文摘In order to provide important parameters for schedule designing, decision-making bases for transit operation management and references for passengers traveling by bus, bus transit travel time reliability is analyzed and evaluated based on automatic vehicle location （AVL） data. Based on the statistical analysis of the bus transit travel time, six indices including the coefficient of variance, the width of travel time distribution, the mean commercial speed, the congestion frequency, the planning time index and the buffer time index are proposed. Moreover, a framework for evaluating bus transit travel time reliability is constructed. Finally, a case study on a certain bus route in Suzhou is conducted. Results show that the proposed evaluation index system is simple and intuitive, and it can effectively reflect the efficiency and stability of bus operations. And a distinguishing feature of bus transit travel time reliability is the temporal pattern. It varies across different time periods.
基金The National Natural Science Foundation of China(No.61573098)the Scientific Research Projects in Universities of Inner Mongolia(No.NJZY16022)
文摘This paper aims to develop a customer satisfaction model for bus rapid transit （BRT）. Both the socio-economic and travel characteristics of passengers were considered to be independent variables. Changzhou BRT was taken as an example and on which on-board surveys were conducted to collect data. Ordinal logistic regression （OLR） was used as the modeling approach. The general OLR-based procedure for modeling customer satisfaction is proposed and based on which the customer satisfaction model of Changzhou BRT is developed. Some important findings are concluded： Waiting sub-journey affects customer satisfaction the most, riding sub- journey comes second and arriving station sub-journey has relatively fewer effects. The availability of shelter and benches at stations imposes heavy influence on customer satisfaction. Passengers＇ socio-economic characteristics have heavy impact on customer satisfaction.
基金The National Basic Research Program of China(973 Program)(No.2012CB725402)the National Natural Science Foundation of China(No.50978057)Program of Scientific Innovation Research of College Graduate in Jiangsu Province(No.CXLX12_0108)
文摘The common phenomenon of uneven headway in bus service is explored based on the automatic vehicle location （AVL） data of Route 2 in Yichun City of Jiangxi province from 6：00 to 9：00 in the morning. The headway regularity of two stages 6： 00--7：00 and 7： 00--9：00 is comparatively analyzed, and it is found that both the traffic conditions and the passenger demand affect headway regularity. A bus arrival model, which assumes that the dwell time of a bus is linear in headway, is built to probe the effect of scheduled headway, and the model is simulated by Matlab. The simulation results reveal that the departure intervals and fluctuations affect headway regularity. Longer intervals and less fluctuation mean higher regularity of headway. And, the fluctuation has a more obvious influence on headway regularity than the interval. Controlling the fluctuations of scheduled headway can effectively raise the regularity of headway and improve the level of public transport service.
基金The National Basic Research Program of China(973 Program)(No.2012CB725402)the National Natural Science Foundation of China(No.51208099,50978057)
文摘To accurately capture the measurement of bus reliability and evaluate whether the transit system is properly operated an evaluation framework is established to assess the reliability of the transit system from different stratifications including stops routes and network levels.The bus operation data of the Hefei city is analyzed as a case study.Comparison is conducted to show the improvement made by using the advanced method and an example of adding exclusive bus lanes to the existing bus route is provided. The proposed advanced method can avoid the shortcomings of the traditional method.For example the value of the reliability using the traditional coefficient of variation CV is not between 0 and 1 and the value of reliability can decrease with the increase in the transit headway etc. The case study shows that the advanced method can represent the real operation condition of the transit system and can be used to evaluate the transit headway reliability more reasonably.
