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2017 7th IEEE International Symposium on Microwave, Antenna, Propagation, and EMC Technologies

作者： YANG DongYing MA LianChuan CAO Yuan School of Electronic and Information Engineering Beijing Jiaotong University National Engineering Research Center of Rail Transportation operation and Control System Beijing Jiaotong University

ISBN: (纸本)9781509059294

In the study of the next generation of CBTC system,the ground equipment is simplified as the object controllers,so the train-ground communication based on TD-LTE technology is put ***,it uses deterministic and stochastic Petri net to establish communication model,and uses TimeNET4.0 to simulate the model,then a conclusion can be concluded that the greater the number of object controllers for communication,the lower the successful rate of receiving,the longer the delay of *** the train gets closer to the base station,as the quantity of object controllers increases,the successful rate of receiving changes more slowly and the trend of delay also changes more *** the worst case,when the rate of receiving data successfully can reach 99.9%,the number of object controller which can communicate with train at the same time is less than or equal to *** the delay is less than 100 ms,the number of object controllers which can communicate with train at the same time is less than *** the plan which is overlying wired network with wireless network is used,the reliability is higher,the communication delay is smaller.

关键词： Next Generation Train control system object controller wireless communication deterministic and stochastic Petri net

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HCSP formal modeling and verification method and its application in the hybrid characteristics of a high speed train control system

HCSP formal modeling and verification method and its applica...

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作者： Lv, J. Li, K. Tang, T. Chen, L. National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University China

The high speed train control system is a typical hybrid system, which not only contains a continuous evolution process (train position and speed), but also the discrete event between subsystems. Although some formal methods like HUML, HA and DL have already been used in modeling and verification train control systems, they are not good at describing communication behaviors which are in the interactive process of subsystems. To overcome this problem, we introduce a formal modeling and verification method for hybrid systems. First, we use HCSP to model the behavior of the system. Second, we transit the HCSP models to HA models by introducing some transition rules. Finally we input these HA models to PHAVer which is a tool for verifying safety properties of hybrid systems to automatic verification. Based on the simulation and analysis of a Movement Authority scenario in high speed train control system specifications, the method is proven to be validated. © 2012 WIT Press.

关键词： Railroads

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Study on Automatic Angle Correction Directed by Machine Vision in Power LED Dies Sorting

Study on Automatic Angle Correction Directed by Machine Visi...

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2010 11th International Conference on Electronic Packaging Technology & High Density Packaging(2010 电子封装技术与高密度封装国际会议)

作者： Tao Wu Longwen Wang Kanghua Lin National Numerical Control System Engineering Research Center Huazhong University of Science and TechnologyWuhan430074 DG-HUST Manufacturing Engineering Institute

All dies are required to keep consistent angles in LED chip sorting. Generally, all chips are adhesive to wafer tape. When each die rotates, all other dies rotate and their positions change. To solve this problem, an on-line angle correction method is put forward. Techniques including reverse computing angle offset and moving displacement for die angle correction are discussed in detail. While, experimental results disclose that it is not enough for power LED die angle correction. Active visual rectification is then used for this. In this way, each correction is done by machine vision detects. Experimental results show that many deficiencies are eliminated and maximum value of die angle declination can be corrected to less than 1.25°. It can be concluded that final effects for angle correction has been better.

关键词： LED active visual rectification pre-correction.

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Sex-Specific Effects of Prenatal Exposure to Endocrine Disrupting Chemicals on Adverse Birth Outcomes: Results from the Korean Children's Environmental Health Study (Ko-Chens)

SSRN

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SSRN 2025年

作者： Oh, Jongmin Shah, Surabhi Lee, Kyung A. Park, Eunkyo Lee, Dong-Wook Hong, Yun-Chul Song, Sanghwan Kim, Sung Yeon Park, Huibyeol Ha, Eunhee Kim, Suejin Park, Choonghee Song, Sanghwan Lee, Jueun Park, Huibyeol Jo, JungHeum Jung, A-Ra Yu, Seung Do Kim, Hyun Jeong Jung, Soon-Won Hong, Sooyeon Seo, Heung Won Hwang, Namkyoung Kang, Tack Shin Jeong, Dong Jin Lee, Seungjune Kim, Hwan-Cheol Jeong, Kyoung Sook Kim, Byungmi Lee, Seulbi Kim, Hyesook Kook, Hoon Baek, Hee Jo Moon, Jai Dong Park, Won Ju Shin, Myung-Geun Ha, Mina Paik, Ki-Chung Kwon, Ho-Jang Lim, Myung-Ho Yoo, Seung Jin Bae, Sanghyuk Kim, Jin Kyung Bae, Jisuk Hong, Young-Seoub Kim, Yu-Mi Son, Hyunjin Park, Mi-Hye Lim, Dae Hyun Kim, Jeong Hee Hong, Sung-Chul Lee, Keun Hwa Kim, Su-Young Kim, Woo Jin Na, Sunghun Lim, Myoung-Nam Yoo, Young Song, Dae Jin Lee, Jue Seong Yoon, Wonsuck Choe, Seung-Ah Kim, Seunghyun Choung, Ji Tae Kim, Sukyung Kim, Jihyun Ahn, Kangmo Hong, Yun-Chul Choi, Baek-Yong Ryoo, Seung-Woo Son, Seok-Yoon Lee, Ji-Hyeon Lee, Dong-Wook Woo, KuckHyeun Yoon, Seong Yong Hur, Jongil Choi, Kyung-Hwa Park, Myung-Sook Lee, Seung-Hwa Chu, Yeonhee Kim, Jung-Ah Kim, Yangho Lee, Jiho Sim, Chang Sun Kim, A. Ram Oh, Inbo Department of Environmental Medicine School of Medicine Ewha Womans University Seoul Korea Republic of College of Medicine Ewha Womans University Seoul Korea Republic of Department of Human Systems Medicine College of Medicine Seoul National University Seoul Korea Republic of Department of Obstetrics and Gynecology Ewha Womans University College of Medicine Seoul Korea Republic of Department of Occupational and Environmental Medicine Inha University Hospital Inha University Incheon Korea Republic of Institute of Environmental Medicine Medical Research Center Seoul National University Korea Republic of Environmental Health Research Division National Institute of Environmental Research Incheon Korea Republic of Graduate Program in System Health Science and Engineering Ewha Womans University Ewha Medical Research Institute College of Medicine Seoul Korea Republic of Environmental Health Research Division Department of Environmental Health Research National Institute of Environmental Research Ministry of Environment Incheon Korea Republic of Environmental Health Policy Division Office of Environmental Health Ministry of Environment Sejong Korea Republic of Department of Occupational and Environmental Medicine Inha University School of Medicine Incheon Korea Republic of Department of Occupational and Environmental Medicine Wonju Severance Christian Hospital Wonju College of Medicine Yonsei University Wonju Korea Republic of Division of Cancer Prevention National Cancer Control Institute National Cancer Center Goyang Korea Republic of Department of Big Data Strategy National Health Insurance Service Wonju Korea Republic of Department of Food and Nutrition Wonkwang University Iksan Korea Republic of Environmental Health Center for Childhood Leukemia and Cancer Department of Pediatrics Chonnam National University Hwasun Hospital Hwasun Korea Republic of Environmental Health Center for Childhood Leukemia and Cancer Department of Occupational and

Objectives Although previous epidemiological studies have reported the effects of fetal exposure to phthalates and phenols on birth outcomes, evidence is limited. The objective of this study was to investigate whether prenatal exposure to endocrine-disrupting chemicals [EDCs;phthalates and bisphenol A (BPA)] is associated with birth outcomes and whether there are sex-specific *** We used data from the Korean CHildren’s ENvironmental health Study (Ko-CHENS) cohort. Exposure to phthalates and BPA was measured by urine tests, and the information on outcomes and confounders was obtained from delivery records, biomarker assessment, and a self-reported questionnaire. We performed multivariate logistic regression to estimate the association between exposure to individual EDCs and each birth outcome. Additionally, to evaluate the effects of EDC mixture exposure, we performed weighted quantile sum regression analysis. Subgroup analysis stratified by maternal age and sex at birth was performed to examine potential differences in *** This study included 2,176 mother-child pairs from the Ko-CHENS. We observed a significant association between the risk of PTB and exposure to BPA during early pregnancy and mono-carboxyoctyl phthalate (MCOP) during late pregnancy, with odds ratios of 1.23 (95% CI: 1.01, 1.49) and 1.29 (95% CI: 1.03, 1.62), respectively. Additionally, there was a positive association between exposure to MCOP during early pregnancy and the risk of LBW (OR: 1.39, 95% CI: 1.03, 1.89). For male infants, exposure to MCOP during early pregnancy was associated with the risk of LBW (OR: 2.44, 95% CI: 1.43, 4.15), and exposure to MCOP during late pregnancy was associated with the risk of PTB (OR 1.45, 95% CI: 1.05, 2.02).Conclusions This study presents quantitative evidence for the association between prenatal exposure to EDCs, especially BPA and MCOP, and PTB/LBW. Moreover, the effect was particularly pronounced for older mothers (≥35 years) an

关键词： Obstetrics

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Improvement of key management mechanism for RSSP-II and its formal modeling and verification 1

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4th International Conference on Electrical and Information Technologies for Rail Transportation, EITRT 2019

作者： Lian, Huozhen Ma, Lianchuan Cao, Yuan School of Electronic and Information Engineering Beijing Jiaotong University Beijing China National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University Beijing China

ISBN: (数字)9789811529146

ISBN: (纸本)9789811529139

As the RSSP-II protocol has hidden dangers in the management of transport keys and authentication keys, in order to strengthen the safety of the key management of RSSP-II and make the communication between the safety-related entities of the train control system safer and more reliable, an improved scheme is presented in this paper. This scheme adopted the Raft algorithm combined with elliptic curve cryptography and time-triggered mechanism to get all safety-related devices in a certain area of the system to update and consistently share an authentication key in a way that works without key management center and reduces human intervention. Then, the specification language TLA+ is used to model the consensus process, and the TLC model checker is used to verify the properties of the model. The results show that the scheme is feasible, safe and can simultaneously avoid the deadlock problem. At last, the safety analysis shows that the scheme is safe and meets EN50159 standard. © Springer Nature Singapore Pte Ltd. 2020.

关键词： Authentication

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Test Suite Generation for CTCS-3 Train control system Based on TAIO and Mutation Theory 21

Test Suite Generation for CTCS-3 Train Control System Based ...

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21st IEEE International Conference on Intelligent Transportation systems, ITSC 2018

作者： Wang, Tuo Lv, Jidong Wei, Baiquan Tang, Tao Shangguan, Wei National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University Beijing China School of Electronic and Information Engineering Beijing Jiaotong University Beijing China

ISBN: (纸本)9781728103235

As a safety-critical system, the Chinese Train control system Level 3 (CTCS-3) have complex fault modes. To generate test suite, which can cover all known faults, is very difficult. In this paper, we proposed a methodology of generating test suite for CTCS-3 train control system based on timed automata with input and output (TAIO) and mutation testing theory. Firstly, according to the characteristics of the fault modes in CTCS-3, mutation operators that contain all known faults of mode transition function ('change action', 'change target', 'change source', etc) are designed. Secondly, the TAIO model of mode transition (TAIO A) in CTCS-3 is established. With each mutation operator, mutants of mode transition timed automata model (TAIO M) are built. Test suites are generated based on the conformance relation of TAIO A and TAIO M using the k-Bounded model checking technique. Finally, the coverage of the test suites have been analyzed by the conformance relation score (CRS), average conformance relation score (ACRS) and weighted conformance relation score (WCRS). Three fault modes of 'change action', 'change invariant' and 'sink location' could be covered effectively and completely detected, wherever, two fault modes coverage of 'negate guard' and 'invert reset' are not high enough, which need additional observation to detect. © 2018 IEEE.

关键词： Automata theory

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Complete Test Suite for the CTCS-3 Target Speed Monitor Based on IECP Test Theory 21

Complete Test Suite for the CTCS-3 Target Speed Monitor Base...

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21st IEEE International Conference on Intelligent Transportation systems, ITSC 2018

作者： Zheng, Wei Hu, Zhuolin Tang, Tao Lv, Jidong Shangguan, Wei National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University Beijing China School of Electronic and Information Engineering Beijing Jiaotong University Beijing China

ISBN: (纸本)9781728103235

The distance-to-go curve, which performs the safety critical functions of the Chinese Train control system Level 3 (CTCS-3), is characterized by large input domain parameters and complex fault modes. It is very difficult to completely test the distance-to-go curve of train onboard equipment. In this paper, a method of generating complete test suite for the CTCS-3 Target Speed Monitor (TSM) has been presented, based on Input Equivalence Class Partitioning (IECP) test theory. Firstly, according to the system requirement specification (SRS) of CTCS-3, the finite state machine models of TSM are built, which satisfy the different brake control modes of driver with high Priority and Automatic Train Protection (ATP) with high Priority. Secondly, the Input/Output (I/O) equivalence and the equivalence class partition theory are applied to obtain two kinds of IECPs with different braking control modes. Finally, the fault models and fault domain of system under test (SUT) are introduced. Two complete test suites of TSM are generated, which can detect any faults in its given fault domain. Different brake control modes in TSM have been compared, in which the ATP with high Priority control mode has a higher test cases number, but more time and memory consumption. © 2018 IEEE.

关键词： Safety engineering

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Hybrid causal methodology in quantitative risk assessment for the on-board ATP of high speed railway 10

Hybrid causal methodology in quantitative risk assessment fo...

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10th Symposium on Formal Methods for Automation and Safety in Railway and Automotive systems, FORMS/FORMAT 2014

作者： Ren, Dewang Zheng, Wei National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University China Institute of Traffic Safety and Automation Engineering Technical University of Braunschweig Braunschweig Germany

ISBN: (纸本)9783981688665

This paper presents a quantitative risk assessment method based on the use of hybrid causal logic in the socio-technical system, the influence in the technological aspects is analyzed as well as in the operational aspects. Different modeling techniques and analyzing methods are applied in this paper aiming at different angles in the socio-technical system. Event tree and fault tree are used to identify the deterministic causal paths between components, the non-deterministic causal relationships (especially focusing on the impact of human factors and organization) are determined with BNs (Bayesian networks) combining evidence theory and ! method. This paper has two objectives: One is that the hybrid causal framework for high-speed railway on-board ATP (Automatic Train Protection) equipment is presented to assess risks quantitatively. The other is that the influence of non-deterministic factors (human factors and organization) in ATP equipment is analyzed combining with Bayesian network, ! method and evidence theory.

关键词： Bayesian networks

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Optimization of operating strategy for smooth operation of heavy haul train 7

Optimization of operating strategy for smooth operation of h...

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2022 7th International Conference on Electronic Technology and Information Science, ICETIS 2022

作者： Lan, Hongyong Liang, Ziyue Yu, Huazhen Tai, Guoxuan Huang, Youneng School of Electronics and Information Engineering Beijing Jiaotong University Beijing China National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University Beijing China

ISBN: (纸本)9783800757794

To address the difficulty of train operating on the long steep down-slopes, this paper proposes an optimization method of operating strategy for smooth operation of heavy haul train. Taking the practical operational regulations of heavy haul train into consideration, an optimization model of smooth operation is established with the optimization objective of minimizing the in-train force. Then, the multi-population strengthen elitist genetic algorithm with opposition-based learning initialization strategy (MSEGA-OBL) is proposed to solve the optimization problem of operating strategy. Based on the actual field data of Shuohuang railway, the simulation experiments are carried out to obtain the optimal driving curve. The simulation results demonstrate the effectiveness of the proposed method. © VDE VERLAG GMBH ∙ Berlin ∙ Offenbach.

关键词： Genetic algorithms

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Optimization of Energy-Saving Operation Strategy for Virtual Coupling based on DDPG

Optimization of Energy-Saving Operation Strategy for Virtual...

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2023 China Automation Congress, CAC 2023

作者： Lv, Wenbo Liu, Hongjie Lang, Yinghui Luo, Xiaolin School of Electronics and Information Engineering Beijing Jiaotong University Beijing China Beijing Jiaotong University National Engineering Research Center of Rail Transportation Operation and Control System Beijing China

ISBN: (纸本)9798350303759

Virtual coupling has emerged as a prominent research focus in the railway industry in recent years. At present, the existing research on synchronous operation of virtually coupled trains focuses on synchronization but neglects energy-saving. In pursuit of minimizing energy consumption, while ensuring synchronous operation, a virtual coupling speed curve optimization method based on deep deterministic policy gradient (DDPG) is proposed. Firstly, the virtually coupled trains are considered to build an optimization model aiming at energy-saving, synchronous parking, synchronous departure and on-time operation. Secondly, considering the characteristics of high state dimension and difficult solution of optimization model, a speed curve solving algorithm based on DDPG is designed. The optimal speed curve is considered a benchmark or reference for virtually coupled trains. Finally, the results of numerical experimental using the data of Beijing Metro Line demonstrate that the proposed method can reduce the traction energy consumption by 5.8% and the arrival time difference by 50%. In comparison to with genetic algorithms (GA), the optimization results are more energy-efficient and synchronous. © 2023 IEEE.

关键词： Curve fitting

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