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Wang Z.,Southwest Jiaotong University | Guo J.,Southwest Jiaotong University | Zhang Y.,Southwest Jiaotong University | Luo R.,Beijing Urban Construction Design and Development Group Co.
ICHVE 2016 - 2016 IEEE International Conference on High Voltage Engineering and Application | Year: 2016

The track circuit electrical insulated joint faults will lead to the false acceptance of control information for trains and it will affect the safe operation of trains. In this paper the locomotive signal induced voltage model is established based on uniform transmission line theory and the amplitude envelopes of the induced voltage when the electrical insulated joint has malfunctioned are simulated. The fault features extraction is achieved through empirical mode decomposition (EMD) method because of its adaptive advantage. The induced voltage amplitude envelope signals are decomposed into several intrinsic mode functions (IMFs) and the IMF energy moments are used as fault characteristics. The least squares support vector machines (LS-SVMs) are built to realize the multi-class classification. Moreover, the optimal parameters of LS-SVM model are obtained by using the improved PSO algorithm. The experiment shows that the fault diagnosis method for track circuit proposed in this paper is effective and the accuracy is higher than the conventional track circuit fault diagnosis approaches. © 2016 IEEE.


Yang D.,Beijing Institute of Technology | Yang D.,Beijing Urban Construction Design and Development Group Co. | Ren W.,University of California at Riverside | Liu X.,Beijing Institute of Technology | Chen W.,Xidian University
Automatica | Year: 2016

In this paper, the event-triggered consensus problem is studied for multi-agent systems with general linear dynamics under a general directed graph. Based on state feedback, we propose a decentralized event-triggered consensus controller (ETCC) for each agent to achieve consensus, without requiring continuous communication among agents. Each agent only needs to monitor its own state continuously to determine when to trigger an event and broadcast its states to its out-neighbors. The agent updates its controller when it broadcasts its states to its out-neighbors or receives new information from its in-neighbors. The ETCC can be implemented in multiple steps. it is proved that under the proposed ETCC there is no Zeno behavior exhibited. To relax the requirement of continuous monitoring of each agent's own states, we further propose a self-triggered consensus controller (STCC). Simulation results are given to illustrate the theoretical analysis and show the advantages of the event-triggered and self-triggered controllers proposed in this paper. © 2016 Elsevier Ltd. All rights reserved.


Zhai W.,Southwest Jiaotong University | Yang J.,China Railway Eryuan Engineering Group Co. | Li Z.,Southwest Jiaotong University | Han H.,Beijing Urban Construction Design and Development Group Co.
Wind and Structures, An International Journal | Year: 2015

A numerical model for analyzing air-train-track interaction is proposed to investigate the dynamic behavior of a high-speed train running on a track in crosswinds. The model is composed of a train-track interaction model and a train-air interaction model. The train-track interaction model is built on the basis of the vehicle-track coupled dynamics theory. The train-air interaction model is developed based on the train aerodynamics, in which the Arbitrary Lagrangian-Eulerian (ALE) method is employed to deal with the dynamic boundary between the train and the air. Based on the air-train-track model, characteristics of flow structure around a high-speed train are described and the dynamic behavior of the high-speed train running on track in crosswinds is investigated. Results show that the dynamic indices of the head car are larger than those of other cars in crosswinds. From the viewpoint of dynamic safety evaluation, the running safety of the train in crosswinds is basically controlled by the head car. Compared with the generally used assessment indices of running safety such as the derailment coefficient and the wheel-load reduction ratio, the overturning coefficient will overestimate the running safety of a train on a track under crosswind condition. It is suggested to use the wheel-load reduction ratio and the lateral wheel-rail force as the dominant safety assessment indices when high-speed trains run in crosswinds. Copyright © 2015 Techno-Press, Ltd.


Wei Y.,Beijing Urban Construction Design and Development Group Co. | Lin S.,North China University of Technology | Chu R.,North China University of Technology | Tian Q.,North China University of Technology | Fei W.,China Aerospace Science and Technology Corporation
Procedia Engineering | Year: 2016

This paper summarizes the classification method of domestic subway station, and points out the existing defects. In order to design of a relatively reasonable grading system, this paper reference to the existing classification method and passenger flow data. First, obtain a dynamic correction of parameters according to the static factors. Then, combine with the data of dynamic flow to determine the level of the station. © 2016 The Authors. Published by Elsevier Ltd.


Han Y.,Beijing Urban Construction Design and Development Group Co. | Liu H.,Huazhong University of Science and Technology
Geomechanics and Engineering | Year: 2016

Explosions inside transportation tunnels might result in failure of tunnel structures. This study investigated the failure mechanisms of circular cast-iron tunnels in saturated soil subjected to medium internal blast loading. This issue is crucial to tunnel safety as many transportation tunnels run through saturated soils. At the same time blast loading on saturated soils may induce residual excess pore pressure, which may result in soil liquefaction. A series of numerical simulations were carried out using Finite Element program LS-DYNA. The effect of soil liquefaction was simulated by the Federal Highway soil model. It was found that the failure modes of tunnel lining were differed with different levels of blast loading. The damage and failure of the tunnel lining was progressive in nature and they occurred mainly during lining vibration when the main event of blast loading was over. Soil liquefaction may lead to more severe failure of tunnel lining. Soil deformation and soil liquefaction were determined by the coupling effects of lining damage, lining vibration, and blast loading. The damage of tunnel lining was a result of internal blast loading as well as dynamic interaction between tunnel lining and saturated soil, and stress concentration induced by a ventilation shaft connected to the tunnel might result in more severe lining damage. © 2016 Techno-Press, Ltd.


Zheng J.,Beijing Urban Construction Design and Development Group Co. | Sa L.,Transport Planning and Research Institute | Guo Y.,Qingdao Guoxin Jiaozhou Bay Transportation Co.
Modern Tunnelling Technology | Year: 2014

In this paper, a three-axial loading device of plane strain is used for a laboratory model test. Contrast tests are carried out for three kinds of anchor bolt arrangements, i.e., an arrangement with no anchor bolts, a whole-section arrangement of anchor bolts, and an arrangement of anchor bolts on the sidewall. The role of the anchor bolt system in a loess subway tunnel is studied in reference to field test results. Data regarding anchor bolts applied to a loess subway tunnel are obtained by model testing, and "loading-before-excavation" and anchor-lining integration are realized. By contrast, the development of a plastic zone around the working face is well controlled by the anchor bolt system; after excavation and support of the tunnel cavern, the sidewall anchor bolt can comply quickly with surrounding rock stress and effectively improve the stress distribution of the lining. Considering the economic factors, the sidewall anchor support system is a good method for reinforcing surrounding rock in shallow-bored loess subway tunnels and should be adopted in actual construction. ©, 2014, Editorial Office of "Modern Tunnelling Technology". All right reserved.


Yu Y.,Beijing Urban Construction Design and Development Group Co. | Liu X.,Chongqing Jiaotong University | Zhang X.,Chongqing Jiaotong University
Modern Tunnelling Technology | Year: 2014

When the bench method is used for the excavation of a multi-arch loess tunnel, steel rib support and backfill support are commonly used for the temporary support of the middle pilot heading. Using the Qingliangsi multi-arch tunnel on the Taiyuan-Jiaxian Expressway as an example, a comparative analysis of overall elastic-plastic simulation was carried out for those two kinds of supporting methods in order to select the most logical temporary support. The results show that the steel rib and backfill supporting methods have the same supporting effects on the surface displacement, crown settlement, and bolt axial force, and both of them can meet the requirements for tunnel deformation. However, the support provided by steel ribs in terms of the surrounding rock stress, initial support stress, and bolt axial force is better than that provided by the backfill support.


Han Y.,Beijing Urban Construction Design and Development Group Co. | Zhang L.,Beijing Urban Construction Design and Development Group Co. | Yang X.,Beijing Urban Construction Design and Development Group Co.
Procedia Engineering | Year: 2016

A series of numerical simulations were carried out to study the interaction between subway tunnels and soils subjected to medium internal blast loading (< 200 kg of TNT equivalent). The excess pore-water pressure was studied with an existing soil model (FHWA) that can simulate pore-water pressure and effective soil pressure. A recently developed blast loading scheme that removes the necessity of modeling the explosive in the numerical models but still maintains the advantages of nonlinear fluid-structure interaction was used to study the process of blast wave propagation in the air domain inside the tunnel. © 2016 The Authors. Published by Elsevier B.V.


Xu B.-C.,China University of Petroleum - Beijing | Lin Z.-H.,China University of Petroleum - Beijing | Zhang Y.-D.,Beijing Urban Construction Design and Development Group Co. Ltd | Xiao Y.-Y.,China University of Petroleum - Beijing
Mathematical Problems in Engineering | Year: 2016

In order to identify the parameters of nonlinear Hammerstein model which are contaminated by colored noise and peak noise, the least absolute deviation (LAD) is selected as the objective function to solve the problem of large residual square when the identification data is disturbed by the impulse noise which obeys symmetrical alpha stable (S α S) distribution. However, LAD cannot meet the need of differentiability required by most algorithms. To improve robustness and to solve the nondifferentiable problem, an approximate least absolute deviation (ALAD) objective function is established by introducing a deterministic function to replace absolute value under certain situations. The proposed method is derived from ALAD criterion and extended stochastic gradient method. Due to the differentiability of the objective function, we can get a recursive identification algorithm which is simple and easy to calculate compared with LAD. The convergence of the proposed identification method is also proved by Lyapunov stability theory, and the simulation experiments show that the proposed method has higher accuracy and stronger robustness than the least square (LS) method in the identification of Hammerstein model with colored noise and impulse noise. The impact of impulse noise can be restrained effectively. © 2016 Bao-chang Xu et al.


Tian Q.,North China University of Technology | Lin S.,North China University of Technology | Wei Y.,Beijing Urban Construction Design and Development Group Co. | Fei W.W.,China Aerospace Science and Technology Corporation
Advances in Energy, Environment and Materials Science - Proceedings of the International Conference on Energy, Environment and Materials Science, EEMS 2015 | Year: 2016

In this paper, combined with the existing algorithm of human detection and the depth camera, a human detection system under the Android system was set. Depth information and color information of the scene can be obtained by depth camera. According to depth information and threshold segmentation method, the area of head and shoulder is determined. Then the histogram of oriented gradient is extracted from the head and shoulder region. And the support of vector machine is used to classify and identify the target. © 2016 Taylor & Francis Group, London.

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