Based on a car-following model, in this paper, we propose a new traffic model for simulating train movement in railway traffic. In the proposed model, some realistic characteristics of train movement are considered, s...Based on a car-following model, in this paper, we propose a new traffic model for simulating train movement in railway traffic. In the proposed model, some realistic characteristics of train movement are considered, such as the distance headway and the safety stopping distance. Using the proposed traffic model, we analyse the space-time diagram of traffic flow, the trajectory of train movement, etc. Simulation results demonstrate that the proposed model can be successfully used for simulating the train movement. Some complex phenomena can be reproduced, such as the complex acceleration and deceleration of trains and the propagation of train delay.展开更多
传统的货车运行故障动态图像检测系统(trouble of moving freight car detection system,TFDS)通过图像采集加人工判读的方式完成车辆状态检查和分析,费时费力。近年来,随着人工智能的发展,TFDS系统中逐渐加入智能识别算法,但受限于样...传统的货车运行故障动态图像检测系统(trouble of moving freight car detection system,TFDS)通过图像采集加人工判读的方式完成车辆状态检查和分析,费时费力。近年来,随着人工智能的发展,TFDS系统中逐渐加入智能识别算法,但受限于样本量少、环境复杂等因素,智能识别算法的识别准确率仍不能满足工程应用要求。为此,文中提出一种基于反馈修正弱光增强的运煤火车外观状态智能检测识别方法,实现高效高精度智能识别车辆外观状态。首先,为解决户外环境光线不断变化带来的弱光图像质量影响智能识别算法准确率的问题,比较研究了六种弱光增强算法对原始图像的预处理性能及其对火车车厢目标识别准确率的影响。结果表明:应用URetinex-Net方法增强后,火车车厢目标识别准确率可以从55%提升到90%。另外,为了解决车辆异常状态的样本数据量有限带来的火车车辆外观状态检测识别与建模过程中严重的数据不均衡问题,文中提出通过多次迭代训练加反馈修正的方式不断提高目标检测模型的准确率,可将识别准确率提升到95.2%。目前该系统已部署于某铁路运煤区间站点并平稳运行,提高了工作效率,具有较高的推广和应用价值。展开更多
The purpose of this study was to propose indicators for grasping autistic characteristics of people with intellectual disabilities who were going to engage in agricultural vocational training. We analyzed the data of ...The purpose of this study was to propose indicators for grasping autistic characteristics of people with intellectual disabilities who were going to engage in agricultural vocational training. We analyzed the data of the Childhood Autism Rating Scale (CARS) of 44 students at the high school course of a special needs education school who participated in agricultural vocational training. The data were divided into two groups according to the scores of “General Impressions”, one of 15 question items of the CARS: one was the group whose score was 1 (usual), and the other was the group whose scores were 1.5 to 4 (unusual). The results of the Mann-Whitney U test showed significant differences between two groups in eight items including “Relating to People” (p Relating to People” with six other items. As a result, “Relating to People” was considered to be the most effective item to know the participant’s autistic characteristics at a very early stage of training. Eventually, adding two items, “Body Use” and “Imitation” which are necessary to master agricultural tasks, to “Relating to People”, we proposed three indicators.展开更多
Peripheral arterial disease (PAD) affects 12% - 20% of the population over 65 years. PAD is a component of systemic atherosclerosis and is associated with increased rate of all-cause mortality and cardiovascular event...Peripheral arterial disease (PAD) affects 12% - 20% of the population over 65 years. PAD is a component of systemic atherosclerosis and is associated with increased rate of all-cause mortality and cardiovascular events, compared with those without PAD. The strongest risk factors for PAD are older age and cigarette smoking. PAD accelerates functional decline leading to physical disability. Many randomized clinical trials demonstrated that treadmill walking training increases pain-free and maximal walking distances in patients with PAD. Exercise intervention is strongly recommended for patients with PAD and symptoms of intermittent claudication (IC). The need to provide an exercise training program to patients with peripheral arterial disease is essential, as almost half of these patients will eventually develop coronary artery disease. There are many existing treadmill walking protocols for patients with PAD. Most of these are based on claudication severity. We present a case of significant improvement of pain-free distance and maximum treadmill walking distance in a patient with PAD after 12 weeks of walking training program utilizing the “2/3 claudication distance” formula.展开更多
There exist three problems in the calculation of lateral vibration of the train-track time-variant system athome and abroad and the method to solve them is presented. Spatially coupling vibration analysis model of tra...There exist three problems in the calculation of lateral vibration of the train-track time-variant system athome and abroad and the method to solve them is presented. Spatially coupling vibration analysis model of train-track time-variant system is put forward. Each vehicle is modeled as a multi-body system with 26 degrees of freedomand the action of coupler is also considered. The track structure is modeled as an assembly of track elements with 30degrees of freedom, then the spatially coupling vibration matrix equation of the train-track time-variant system is es-tablished on the basis of the principle of total potential energy with stationary value and the "set-in-right-position"rule. The track vertical geometric irregularity is considered as the excitation source of the vertical vibration of thesystem, and the hunting wave of car bogie frame is taken as the excitation source of lateral vibration of the system.The spatially coupling vibration matrix equation of the system is solved by Wilson-θ direct integration method. Theapproximation of the calculated results to the spot test results demonstrates the feasibility and effectiveness of thepresented analysis method. Finally, some other vibration responses of the system are also obtained.展开更多
Optimizing train movement has a great significance for railway traffic. In this paper, based on the optimal velocity car-following model, we propose a new simulation model for optimizing train movement in railway traf...Optimizing train movement has a great significance for railway traffic. In this paper, based on the optimal velocity car-following model, we propose a new simulation model for optimizing train movement in railway traffic. Here a kind of single-track railway is considered. Our aim is to reduce the energy consumption of train movement and ensure the train being on time by controlling the velocity curve of train movement. The simulation results indicate that the proposed model is effective for optimizing train movement. In addition, some major characteristics of train movement can be well captured. This method provides a new way to optimize train movement in railway traffic.展开更多
[目的]目前,列车运营能耗与运营效益间的矛盾日益凸显,已成为各发展阶段达成节能环保指标的首要问题,因此有必要研究列车轻量化方案,以达到列车减重的目的。[方法]基于车体结构传统材料(奥氏体不锈钢、低合金高强钢、耐候钢),结合列车...[目的]目前,列车运营能耗与运营效益间的矛盾日益凸显,已成为各发展阶段达成节能环保指标的首要问题,因此有必要研究列车轻量化方案,以达到列车减重的目的。[方法]基于车体结构传统材料(奥氏体不锈钢、低合金高强钢、耐候钢),结合列车性能及功能(能耗、运量、强度及外观、系统接口等)需求,分析适用于较低轴重、较大载客量、等断面直车体且多开口的地铁车体结构,并提出进一步提升车体结构轻量化程度的方法。在传统材料、现有制造工装系统及设备的基础上,通过有限元分析软件构建优化的车体结构模型,并利用车体强度试验对其进行验证。[结果及结论]在EN12663-1:2010+A1:2014 Railway applications-Structural requirements of railway vehicle bodies-Part 1:Locomotives and passenger rolling stock(and alternative method for freight wagons)标准框架下,所提优化车体结构模型较同类车体结构的总质量降低了约9.5%,且实现了一次性通过对角架车试验的目标。展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos 60634010 and 60776829)the New Century Excellent Talents in University,China (Grant No NCET-06-0074)the Key Project of Ministry of Education,China (GrantNo 107007)
文摘Based on a car-following model, in this paper, we propose a new traffic model for simulating train movement in railway traffic. In the proposed model, some realistic characteristics of train movement are considered, such as the distance headway and the safety stopping distance. Using the proposed traffic model, we analyse the space-time diagram of traffic flow, the trajectory of train movement, etc. Simulation results demonstrate that the proposed model can be successfully used for simulating the train movement. Some complex phenomena can be reproduced, such as the complex acceleration and deceleration of trains and the propagation of train delay.
文摘传统的货车运行故障动态图像检测系统(trouble of moving freight car detection system,TFDS)通过图像采集加人工判读的方式完成车辆状态检查和分析,费时费力。近年来,随着人工智能的发展,TFDS系统中逐渐加入智能识别算法,但受限于样本量少、环境复杂等因素,智能识别算法的识别准确率仍不能满足工程应用要求。为此,文中提出一种基于反馈修正弱光增强的运煤火车外观状态智能检测识别方法,实现高效高精度智能识别车辆外观状态。首先,为解决户外环境光线不断变化带来的弱光图像质量影响智能识别算法准确率的问题,比较研究了六种弱光增强算法对原始图像的预处理性能及其对火车车厢目标识别准确率的影响。结果表明:应用URetinex-Net方法增强后,火车车厢目标识别准确率可以从55%提升到90%。另外,为了解决车辆异常状态的样本数据量有限带来的火车车辆外观状态检测识别与建模过程中严重的数据不均衡问题,文中提出通过多次迭代训练加反馈修正的方式不断提高目标检测模型的准确率,可将识别准确率提升到95.2%。目前该系统已部署于某铁路运煤区间站点并平稳运行,提高了工作效率,具有较高的推广和应用价值。
文摘The purpose of this study was to propose indicators for grasping autistic characteristics of people with intellectual disabilities who were going to engage in agricultural vocational training. We analyzed the data of the Childhood Autism Rating Scale (CARS) of 44 students at the high school course of a special needs education school who participated in agricultural vocational training. The data were divided into two groups according to the scores of “General Impressions”, one of 15 question items of the CARS: one was the group whose score was 1 (usual), and the other was the group whose scores were 1.5 to 4 (unusual). The results of the Mann-Whitney U test showed significant differences between two groups in eight items including “Relating to People” (p Relating to People” with six other items. As a result, “Relating to People” was considered to be the most effective item to know the participant’s autistic characteristics at a very early stage of training. Eventually, adding two items, “Body Use” and “Imitation” which are necessary to master agricultural tasks, to “Relating to People”, we proposed three indicators.
文摘Peripheral arterial disease (PAD) affects 12% - 20% of the population over 65 years. PAD is a component of systemic atherosclerosis and is associated with increased rate of all-cause mortality and cardiovascular events, compared with those without PAD. The strongest risk factors for PAD are older age and cigarette smoking. PAD accelerates functional decline leading to physical disability. Many randomized clinical trials demonstrated that treadmill walking training increases pain-free and maximal walking distances in patients with PAD. Exercise intervention is strongly recommended for patients with PAD and symptoms of intermittent claudication (IC). The need to provide an exercise training program to patients with peripheral arterial disease is essential, as almost half of these patients will eventually develop coronary artery disease. There are many existing treadmill walking protocols for patients with PAD. Most of these are based on claudication severity. We present a case of significant improvement of pain-free distance and maximum treadmill walking distance in a patient with PAD after 12 weeks of walking training program utilizing the “2/3 claudication distance” formula.
基金Project (50078006) supported by the National Natural Science Foundation of China Project (2001G029) supported by the Foundation of the Science and Technology Section of the Railway Bureau
文摘There exist three problems in the calculation of lateral vibration of the train-track time-variant system athome and abroad and the method to solve them is presented. Spatially coupling vibration analysis model of train-track time-variant system is put forward. Each vehicle is modeled as a multi-body system with 26 degrees of freedomand the action of coupler is also considered. The track structure is modeled as an assembly of track elements with 30degrees of freedom, then the spatially coupling vibration matrix equation of the train-track time-variant system is es-tablished on the basis of the principle of total potential energy with stationary value and the "set-in-right-position"rule. The track vertical geometric irregularity is considered as the excitation source of the vertical vibration of thesystem, and the hunting wave of car bogie frame is taken as the excitation source of lateral vibration of the system.The spatially coupling vibration matrix equation of the system is solved by Wilson-θ direct integration method. Theapproximation of the calculated results to the spot test results demonstrates the feasibility and effectiveness of thepresented analysis method. Finally, some other vibration responses of the system are also obtained.
基金Project supported by the National High Technology Research and Development Program of China (Grant No. 2011AA110502)the National Natural Science Foundation of China (Grant No. 71271022)
文摘Optimizing train movement has a great significance for railway traffic. In this paper, based on the optimal velocity car-following model, we propose a new simulation model for optimizing train movement in railway traffic. Here a kind of single-track railway is considered. Our aim is to reduce the energy consumption of train movement and ensure the train being on time by controlling the velocity curve of train movement. The simulation results indicate that the proposed model is effective for optimizing train movement. In addition, some major characteristics of train movement can be well captured. This method provides a new way to optimize train movement in railway traffic.
文摘[目的]目前,列车运营能耗与运营效益间的矛盾日益凸显,已成为各发展阶段达成节能环保指标的首要问题,因此有必要研究列车轻量化方案,以达到列车减重的目的。[方法]基于车体结构传统材料(奥氏体不锈钢、低合金高强钢、耐候钢),结合列车性能及功能(能耗、运量、强度及外观、系统接口等)需求,分析适用于较低轴重、较大载客量、等断面直车体且多开口的地铁车体结构,并提出进一步提升车体结构轻量化程度的方法。在传统材料、现有制造工装系统及设备的基础上,通过有限元分析软件构建优化的车体结构模型,并利用车体强度试验对其进行验证。[结果及结论]在EN12663-1:2010+A1:2014 Railway applications-Structural requirements of railway vehicle bodies-Part 1:Locomotives and passenger rolling stock(and alternative method for freight wagons)标准框架下,所提优化车体结构模型较同类车体结构的总质量降低了约9.5%,且实现了一次性通过对角架车试验的目标。
