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With the high frequency of highway accidents,studying how to use connected automated vehicle (CAV) to improve traffic efficiency and safety will become an important issue. In order to investigate how CAV can use the connected information for decision making, this study proposed a natural lane changing decision model for CAV to adapt the mixed traffic flow based on extreme value theory. Firstly, on the bias of the mixed vehicle behavior analysis, the acceleration, deceleration, and randomization rules of the cellular automata model of mixed traffic flow in two lanes are developed. Secondly,the maximum value of CAV's lane change probability at each distance by extreme value distribution are modeled. Finally, a numerical simulation is conducted to analyze the trajectory-velocity diagram of mixed traffic flow, average travel time and average speed under different penetration rates of CAV. The result shows that our model can avoid the traffic risk well and significantly improve traffic efficiency and safety.

For enhancing the intelligence of urban traffic, connected automated vehicle (CAV) is recognised as the leading technology in the near future. With on-board sensors and communication devices, status of the vehicles can be obtained to better coordinate the traffic. However, the limited environmental perception range cannot lead to the best efficiency of the global urban traffic. In this study, a three-step evolution strategy of the CAV perception mode is proposed, from autonomous perception to interactive perception to networked perception. Key technologies in these three steps are studied. In autonomous perception, vehicle positioning and dynamic target tracking approaches are proposed. In interactive perception, a reliable multi-mode information exchange mechanism is studied. Finally, a new traffic big data storage and advanced analytics solution in networked perception is introduced. Related experiments about the above key issues are designed, implemented, and verified based on the hardware platform, open source dataset, and cloud platform, respectively. The results show that the positioning distance root mean square achieves 3.9 m, object tracking speed reaches 30fps, and communication average packet loss rate is 2%. As can be seen from testing and simulation results, our proposed approaches can meet technical requirements and support environment perception mode evolution of CAV.

The fault diagnosis and analysis of high-speed train is of great significance for train's safe and highly efficient operation. The complexity and quantity of on-train information which is closely related with fault diagnosis and analysis is increasing rapidly as the development of high-speed railway. Onboard system fault recording files contains lots of important fault information described in short-text which is recorded by maintainers in nature language(NL). This paper makes an analysis on operation and fault information of on-board system recorded in NL based on text mining. The fault text dictionary is constructed for word segmentation, and fault text chain is defined as well as the construction method in order to process the fault recording files. At last, the method is applied to segment the on-board system fault recording files and construct fault text chains, therefore the faults of on-board equipment are analyzed and we obtained the faults' distribution.

Traditional lane-changing (LC) behavioral researches usually focus on the driver’s cognitive performance which includes the driver’s psychological and behavioral habit characteristics, rarely involving the affection of expert driver’s comprehensive behavioral preferences, such as: safety and comfort performance in LC process. Towards the free LC process, a novel LC safety and comfort degree index is proposed in this paper, as well as, the novel definition of LC driving behavioral preferences is described in detail. Taking advantage of interactive evolutionary computing (IEC) and real-time optimization (RTO) metrics, a kind of LC behavioral preferences on-line learning agent extending traditional Belief-Desire-Intention (BDI) structure is explicitly proposed, which can perform behavioral preferences learning activities in the LC process. In addition, driving behavioral preferences learning strategies are introduced which can gradually grasp essentials in driver’s subjective judgments in decision-making of the LC process and make the LC process more safety and scientific. Specifically, a conceptual model of the agent, driving behavioral preferences learning-BDI (DpL-BDI) agent is introduced, along with corresponding functional modules to grasp driving behavioral preferences. Furthermore, colored Petri nets are used to realize the components and scheduler of the DpL-BDI agents. In the end, to compare with the traditional LC parameters’ learning methods (such as: the least squares methods and Genetic Algorithms), a kind of LC problems is suggested to case studies, testing and verifying the validity of the contribution.

Due to the poor environment in the West of China, this research firstly analyzes the application requirements of low density, low cost and high reliability, and then focuses on the integrated BeiDou Navigation Satellite System (BDS) and Inertial Navigation System (INS) to achieve seamless positioning. The map-matching technology in the switch section is studied and its process is discussed and tested, whose accuracy can rise up to 98.6%. On the basis of the above research, a train position system is constructed. The test indicates the positioning precision is less than 3 meters in the differential mode, meeting the demand of the western Low Density Lines.

T rain-ground communication subsystem is a key subsystem in high-speed train control system and plays an important role during the operation of high-speed train. So the reliability of train-ground communication subsystem should be studied in depth. The dynamic fault tree model for train-ground communication subsystem that is modeled based on the structure chart of the subsystem is transformed to Dynamic Bayesian networks. After this, probability of the top event can be obtained by inference algorithm of Bayesian network, and the probability of sub-equipment's failure under the premise of system's failure will be obtained through reverse inference algorithm, which can provide reference information for fault location. The simulations reveal that the reliability of train-ground communication subsystem at any time can be obtained by Dynamic Bayesian Networks method, so we can perform real-time reliability evaluation on train-ground communication subsystem.

System Testing is a key technology of CVIS (Cooperative Vehicle Infrastructure System). A shortest test sequence generating approach in CVIS is proposed in this paper. The paper firstly analyzes the spatial-temporal state of vehicle and complexity of infrastructure in network. Then paper designs system features and test cases, and introduces the concept of support index of the test case to system feature. Then a shortest test sequences generating method and GA method are used to accelerate the convergence speed. The method in this paper provide theoretical basis and implementation guidance in CVIS testing.

Private railway development in Japan is closely related to the evolution of its metropolitan area. Private railway in the Japanese metropolitan area has experienced stages of emerging, booming and government support. Private railway in the Japanese metropolitan area successfully gave rise to social capital investment, promoted the joint development of land, and brought the benign development of marketization operation. Japanese government supported the development of the private railway in terms of policies and funds. Therefore, the development of private railway in Japan has implications for Chinese regional railway to attract social capital and develop diversified management.

Cooperative Intersection Collision Avoidance System (CICAS) program uses roadside radar sensors, a computer processor and algorithms to determine unsafe conditions, and an active LED icon based sign to provide timely alerts and warnings which are designed to reduce the frequency of crashes at rural expressway intersections. The cooperative component of the CICAS system consists of roadside equipment (RSE), on-board equipment (OBE), geospatial information database (GID) and intersection sign state (ISS). Both the RSE and OBE use dedicated short range communication (DSRC) radios operating on the 5.9GHz band. For the tests described in this paper, the supplier of the DSRC radios is Arada. The tests documenting performance were done at the CICAS test intersection located at the intersection of U.S. 169 and County State Aid Highway 13 north of Milaca, MN. The goal of this test was to determine the efficacy with which information can be broadcast from the RSE and received by the OBE as a function of direction and distance of travel from the intersection. The result is it is sufficient to ensure that approaching vehicles will receive a complete GID in sufficient time for its intended use.

A multi-resolution simulation of the cooperative vehicle-infrastructure system is of great significance for traffic-simulation research. An HLA-based framework and simulation models for the cooperative vehicle-infrastructure system are constructed. The HLA/RTI management mechanism can realize transparent data transmission and shield the tedious details of the underlying information interaction. Then this paper focuses on multi-resolution modeling (MRM) of the cooperative vehicle-infrastructure system and analyzes in detail aggregation and disaggregation theory as well as assistance in the MRM. Different MRM methods that apply to subsystems in the train control system are considered in accordance with hierarchical concerns and features of the cooperative vehicle-infrastructure system as being multi-node and distributed.

Train locating information is very important for train control system, how to achieve automatic identification of train track occupancy using GNSS simply in some railway sections without track circuits has been a crucial problem. Hausdorff distance can be used to measure the mismatch between two sets, which is widely used in object matching. This paper presents a novel algorithm for automatic identification of train track occupancy based on LTS-Hausdorff distance and D-S evidence theory. The LTS-Hausdorff distance reference template of railway track was established, the calculation process of LTS-Hausdorff distance and the identify strategy of train track occupancy based on D-S evidence theory were studied. Test results show that the algorithm is efficient and can achieve automatic track identification in low cost.

Based on basic theory and methods of fault injection, the software-based fault injection was constructed for distributed and inter-operated simulation architecture based on High Level Architecture (HLA). The fault test program of communication in train control simulation system was designed. The fault injection tools were used to control train control model. Every module in train control model should follow fault test program to operate. The failure process of train control system could be shown by simulation interface. There are three steps in fault injection. Firstly, fault test program was loaded into fault injection tools; secondly, fault injection tools distributed instructions of fault test program to every related subsystem; thirdly, every subsystem followed the steps during operation. Analysis results shows that fault injection method could be effectively applied in train control simulation system simulation based on HLA to improve reliability of simulation system.

This paper studies Multi-Resolution Modeling (MRM) method of Train Control System based on multi resolution modeling (MRM) and analyses in detail about aggregation-disaggregation theory as well as consistency of MRM. Due to the characteristics of Train Control System as being multi-node and distributed, subsystems of Train Control System using different resolution modeling methods concerning hierarchy and a HLA-based multi-train simulation platform for the Train Control System is built taking RTI time management strategy to realize multi-resolution simulation of the Train Control System. The results show that this simulation strategy could describe its features of distribution and hierarchy correctly and meet the requirements of multi-level and complex system simulation in Train Control System.

With the rapid development of the intelligence and complication to railway systems, there are increasing demands of electromagnetic compatibility performance for train borne system, where the electromagnetic compatibility performance of train positioning system (TPS) is crucial to the design process of the entire system. In this paper, the system architecture of TPS integrating multi sensors is introduced, based on the overall design of the multi-sensor based train integrated positioning system, the electromagnetic interference of the TPS is analyzed at the power module, communication module, transmission and PCB routing, then the electromagnetic compatibility solutions are introduced in hardware and software. Lab test of the TPS validates the performance with proposed strategies.

In the simulation platform of high-speed train control system, it is necessary to simulate the track circuit occupation in order to provide basic conditions for other simulated equipment to calculate movement authority or generate track circuit code. A problem with the simulation of track circuit is that there may be more than one track circuit sections corresponding to one kilometer post. To solve this problem, this paper proposes an algorithm to precisely identify the occupied track circuit sections. In this algorithm, by using the signal machine as a reference origin, in combination with the the route information received from the simulated computer based interlocking equipment, train mileage is increased or decreased based on train running direction to find the occupied track circuit sections. The reference origin is always changing and the occupied track circuits inside or outside the station are identified by a unified “route”. This algorithm can find the occupied track circuit in a route of any complexity and reduce the accumulated error by using the changing reference origin and clearing the train mileage, thus solving the difference between the real and simulated track circuit. This algorithm reduces the complexity of simulating the occupation state of track circuit and lays a foundation for the construction of high-speed train control system simulation platform.

As we all know, freeway solves the problem about the lack of the transportation resources in home and then contributes to the development in economy. However, as economy developed fast, the growing number of motor, together with people's favor to choose freeway, makes freeway full of motor, chaos and congestion. On-ramp control is one of the efficient ways to regulate the flow of traffic entering the freeway and reduce the congestion on freeway. Based on ramp control in freeway and simulation and modeling, which is discussed in home and abroad, this essay used the micro-model, Cellular Automata traffic model (CA) in on-ramp transportation modeling, hoping that the freeway on-ramp transportation model could describe the character of the real on-ramp transportation in freeway; according to the long waiting-queue problem on the on-ramp, signal control system is applied with two different control methods, set-time signal timing method and dynamic signal timing method; based on the simulation results, conclusion is obtained.

Basic principle, composition and classification of European Train Control System (ETCS) are introduced. Train Traction model and Brake model of ETCS controlling Curves are studied, which includes increasing and decreasing curve model. At last, the application and development of ETCS in high-speed railway are introduced, which could be as reference of Chinese train control system controlling curves model.

With high accuracy and storage efficiency, digital track map plays an important role in train positioning system as a special sensor, and directly affects the safety of the train operation control. In this paper, the characteristics of the track are analyzed with practical measurements, a distance discrimination is utilized to reject abnormal data, and a vertical distance criterion and cubic spline curve based algorithm is presented to reduct numerous measurement data and fit the track. By using the distance criterion and vertical distance based local optimum algorithm, a group of feature points are generated to represent the feature of rail tracks. Then the well-fitting cubic spline algorithm is employed to fit the tracks with high precision and optimize the feature point set, and then the smooth tracks could be realized by segmental cubic curves. Validation with practical measurements from Qinghai-Tibet line demonstrate that with a proper limited error of the vertical distance the proposed algorithm could realize data reduction and map generation effectively.

High-speed train control system is one complex security system with lots of functions, which means that it is necessary to build up high-speed train control system simulation & testing integration platform to start function and system verification and validation (VV basic theory of simulation and testing of control system is studied systematically. Aiming at this simulation & testing integration system, testing and evaluation technique are studied systematically based on different system level, as system techniques, equipment, communication, etc, to provide theoretical and technical support to whole system life cycle, and simulation, testing and evaluation techniques of train control system is studied completely.

As we known, how to describe rail track with precise data is one important problem in train positioning research fields, research of variational curve model base on Level Set and GVF (Gradient Vector Flow) was studied systematically and the GPS data reduction model, method and algorithm base on variational curve model in limited restriction condition was studied, combine with real track data, analyzed the limited restriction condition in practical rail application environment, raised the limited restriction mathematical model, using the GPS data reduction algorithm Base on Level Set and GVF variational curve model adapt to different environment to realize data reduction and error point deletion, extract some key point or track data from track database to describe rail track in a certain satisfactory error region. The experiment proves that the algorithm model Base on Level Set and GVF could extract precise positioning information and improve rail track database automatic generation method, which is adapt to precise positioning of train control system base on GPS.

This paper mainly focuses on a GNSS IF signal acquisition platform; the platform is comprised of RF module, control module, buffer module, transmission module and a data acquisition routine. RF module is designed as a single-circuit board to facilitate for replacement, GNSS signal is converted to IF digital signal by filtering, amplifying, down conversion and sampling in the RF module; Programmable logic device is used in control module, so it is flexible and upgradeable. The entire data flow control is completed by programmable logic device; USB2.0 controller is used in transmission module, which provides high speed performance to meet the requirement of GNSS IF signal. It is used to transmit the IF digital signal to the USB bus; Data acquisition routine running on the computer collects GNSS IF digital signal from the USB bus and stores it in the computer's storage medium.

Train operation control system is one complex system with some feature like real-time and distributing, aim at different application purpose and operation process of system lifecycle, the emphasize point and level of detail is different. In this paper, MRM-based Simulation Support Technology and it’s application was studied, the modeling theory and method was studied systematically; the Aggregation-Disaggregation problem and settle method of MRM model run together in distributing simulation was studied, solving the couple consistency problem of MRM model; design the distributing and interactive simulation system structure base on HLA, the simulation support technology base on different level resolution was studied. Aim at practical demand of Chinese railway development, the modeling method base on MRM and modeling system structure aim at different simulation motivation was studied, the MRM modeling of key subsystem and parts of Train operation control system was studied, combine with practical work pattern of key parts, study the simulation of constructed model.

Identification of occupied track is important to train navigation. With traditional train positioning method, it is difficult to identify track occupied in station with several parallel tracks. According to characteristic of switch curve, a track occupied identification method based on the switch curve information is proposed in this paper, in which inertial sensors and GNSS are employed to obtain train's operation state in switch, which will be used for the track occupancy identification. Experimental results demonstrate that the proposed method could realize track occupied identification to some extent with certain application value.

In recent years, vehicles detection base on the magnetic effect is a major hot spot in the field of vehicles detection. This paper has studied and realized a wireless magneto-resistive sensor based vehicles detection system, and improved the vehicle detection algorithm. The thesis has used a testing algorithm based on iterative optimal wavelet threshold used to focus on testing whether vehicles passing by. For the speed detection, the traditional algorithm of speed detection has been improved; a new speed detection method which is based on clock synchronization has been used. In that way the error of speed detection will be minimized. The effectiveness of the algorithms has been tested by using the vehicle detection signals of wireless magneto-resistive sensors. Experimental result shows that, the vehicle detection algorithms are available for the vehicles detection and the speed measurement.

Under the development of high technology, GPS software receiver has been more and more highly developed, thus becoming the hot issue in the GPS receiver research field. This paper demonstrates GPS software receiver using IF signal from the NewStar210A IF signal sampler as the raw data, then using Matlab as the software for signal acquisition and tracking. The navigation data, pseudo range, carrier phase information is got. Carrier Noise Ratio Method is applied to rough capture, while carrier location method is also used to get the users location. The experiment result mentions that carrier noise ratio method is used to improve the speed of acquisition and carrier location method can get a higher positioning accuracy

The low-cost train control system is new trend for modern train operation and management. Based on the functional requirement of track map database, generation of track map in GIS and schematic form are mainly studied in this paper, as well as their mapping description. In the low-cost scheme, the flow of the generation is discussed in detailed and several strategies are employed to realize the mapping of GIS and schematic track. With the generating software developed in this work, the generated track map database is validated in the simulation environment and the correction and effectiveness are guaranteed.

Research of variational curve model in limited restriction condition and application in rail train control track database was studied in this paper, raised the method, model and algorithm for digital track map auto-generation from GPS track data, through lots of testify, comparison and improvement using practical data between those algorithm and method, aim at track data, construct mathematical model of data reduction, analyze the limited restriction condition of practical train operation situation, and studied the curve evolution theory, using the algorithm base on variational curve model evolution theory to realize data reduction and error deletion, obtain a few key data automatically to describe rail track in a certain satisfactory error condition, improve the track database automatic generation and optimization method, realize real-time and precise positioning of rail control system base on GPS.

Because of complexity of CTCS-3 train control system, interworking testing and function evaluation could not be operated directly on the system, which means that deep research on modeling and simulation of train operation control system should be carried out. This paper proposes a modeling and verification method based on UML and colored Petri net. On the basis of analysis of advantages and disadvantages of UML modeling, colored Petri net is used as formal specification of UML modeling, which improves scalability of formal method and make up for the deficiency of UML, as lack of analysis of model and verification method. Aiming at sequence diagram, dynamic model of UML, colored Petri net is suggested as a modeling method. Sequence diagram of communication between on-board and RBC during conversion from CTCS-3 to CTCS-2 is designed and transformed into colored Petri net model. Based on information interaction between objects to each other, colored Petri net model of onboard and RBC is obtained. Using CPN tools, the model is simulated and analyzed boundedness and deadlock of model. Thus, correctness of model is verified.

Precise location of a train on the rail network is important to train control system. The general problem of locating a train on closely-spaced parallel tracks is hard to determine the track occupied by train simply relying on GNSS. Hidden Markov Model (HMM) is widely used in speech processing of a time series model. This paper applied the HMM to the track occupied automatic identification, established the HMM of tracks, resolved the problem of track occupied identification using GNSS, and progressive studied the impact on identification, when changing the state number of the HMM, GNSS output frequency and train speed, then the optimal parameters are determined.

In vehicle surveillance system, it's important to realize digital map because it can easier to know vehicle's dynamic information. In this paper, application of MapX component in vehicle surveillance system is discussed. On the basis of analysis of composition and work principle of vehicle surveillance systems, using Visual C ++and integrating MapX component, realizes function of vehicles orientation, tracks replay, abbreviative map, objects query, then fulfills the design of digital map module of vehicle surveillance system. It's helpful for designing specific system using MapX.

The DArk Matter Particle Explorer (DAMPE) is well suitable for searching for monochromatic and sharp $\gamma$-ray structures in the GeV$-$TeV range thanks to its unprecedented high energy resolution. In this work, we search for $\gamma$-ray line structures using five years of DAMPE data. To improve the sensitivity, we develop two types of dedicated data sets (including the BgoOnly data which is the first time to be used in the data analysis for the calorimeter-based gamma-ray observatories) and adopt the signal-to-noise ratio optimized regions of interest (ROIs) for different DM density profiles. No line signals or candidates are found between 10 and 300 GeV in the Galaxy. The constraints on the velocity-averaged cross section for $\chi\chi \to \gamma\gamma$ and the decay lifetime for $\chi \to \gamma\nu$, both at 95% confidence level, have been calculated and the systematic uncertainties have been taken into account. Comparing to the previous Fermi-LAT results, though DAMPE has an acceptance smaller by a factor of $\sim 10$, similar constraints on the DM parameters are achieved and below 100 GeV the lower limits on the decay lifetime are even stronger by a factor of a few. Our results demonstrate the potential of high-energy-resolution observations on dark matter detection., Comment: 14 pages, 8 figures. Update the content to keep up with the published version