检索结果-内蒙古大学图书馆

Ride-hailing origin-destination demand prediction with spatiotemporal information fusion

Transportation safety and Environment 2024年第2期6卷 63-74页

作者： Ning Wang Liang Zheng Huitao Shen Shukai Li School of Traffic and Transportation Engineering Central South UniversityChangsha 410075China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China

Accurate demand forecasting for online ride-hailing contributes to balancing traffic supply and demand,and improving the service level of ride-hailing *** contrast to previous studies,which have primarily focused on the inflow or outflow demands of each zone,this study proposes a conditional generative adversarial network with a Wasserstein divergence objective(CWGAN-div)to predict ride-hailing origin-destination(OD)demand *** blocks and refined loss functions help to enhance the stability of model *** conditional information is employed to capture external spatiotemporal dependencies and guide the model towards generating more precise *** analysis using ride-hailing data from Manhattan,New York City,demon-strates that our proposed CWGAN-div model can effectively predict the network-wide OD matrix and exhibits strong convergence *** experiments also show that the CWGAN-div outperforms other benchmarking ***,the proposed model displays potential for network-wide ride-hailing OD demand prediction.

关键词： intelligent transport system ride-hailing generative adversarial networks spatiotemporal dependencies origin-destination(OD)demand prediction

来源：评论

学校读者我要写书评

暂无评论

Identification and Assessment of Risk Factors in the Plateau railway System 6th

Identification and Assessment of Risk Factors in the Plateau...

引用

6th International Conference on Electrical Engineering and Information Technologies for rail Transportation, EITRT 2023

作者： Zhang, Yusheng Jia, Limin Qin, Yong Wang, Zhipeng State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China

ISBN: (纸本)9789819993147

How to further improve the safety of plateau railway’s construction and operation has always been a crucial issue. Therefore, research on risk identification of the plateau railway is also imperative. Firstly, based on the risk identification system and methods, this article focuses on the multi-source factors of human machine environment management, and obtains a set of key risk factors covering 359 plateau railway systems based on the accident cause analysis model. Then, make full use of expert experience to conduct risk importance analysis to obtain risk importance values. Finally, the concept of functional importance is introduced to calculate the indicators of risk factors in the model, which are linearly weighted with the risk importance. The comprehensive importance value is obtained as the basis for ranking the final risk factors, and targeted solutions and suggestions are proposed based on the top 10 risk factors of the comprehensive importance. © 2024, Beijing Paike Culture Commu. Co., Ltd.

关键词： Risk assessment

来源：评论

学校读者我要写书评

暂无评论

Spatial Coded Modulation:Coding over Antennas

引用

China Communications 2024年第11期21卷 104-122页

作者： Luo Junshan Wang Fanggang Wang Shilian School of Electronic Science National University of Defense TechnologyChangsha 410073China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China

In spatial modulation systems,the reliability of the active antenna detection is of vital importance since the modulated symbols tend to be correctly demodulated when the active antennas are accurately *** this paper,we propose a spatial coded modulation(SCM)scheme,which improves the accuracy of the active antenna detection by coding over the transmit ***,the antenna activation pattern in the SCM corresponds to a codeword in a properly designed codebook with a larger minimum Hamming distance than the conventional spatial *** the minimum Hamming distance increases,the reliability of the active antenna detection is directly enhanced,which yields a better system *** addition to the reliability,the proposed SCM scheme also achieves a higher capacity with the identical antenna configuration compared to the conventional *** optimal maximum likelihood detector is first ***,a low-complexity suboptimal detector is proposed to reduce the computational *** derivations of the channel capacity and the bit error rate are presented in various channel *** derivation on performance bounding is also provided to reveal the insight of the benefit of increasing the minimum Hamming *** results validate the analysis and demonstrate that the proposed SCM outperforms the conventional spatial modulation techniques in both channel capacity and system reliability.

关键词： antenna correlation channel capacity Hamming distance reliability spatial modulation

来源：评论

学校读者我要写书评

暂无评论

Automatic Generation of Pantograph Image Caption Based on Deep Learning 1

引用

6th International Conference on Electrical Engineering and Information Technologies for rail Transportation, EITRT 2023

作者： Yin, Xinqiang Wei, Xiukun Tang, Qingfeng State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing100044 China

ISBN: (数字)9789819993154

ISBN: (纸本)9789819993147

As the essential component of the pantograph-catenary system, the pantograph operates in a complex environment, and its failure can result in safety accidents during train operations. Currently, there is insufficient research on the automatic generation of pantograph maintenance records. The conventional approach involves manual recording during the maintenance process and manual compilation of maintenance reports, which suffer from issues like human error and heavy reliance on experience. Consequently, this paper proposes the PantoCap model for pantograph image caption. The model uses DenseNet-121, replacing VGG-16, to enhance feature extraction capabilities. Additionally, a relational memory module is devised to preserve the association information among texts. At the same time, the layer normalization module of Transformer decoder is improved, and the calculation method of memory mask is added to improve the processing of memory information during model decoding. Finally, the effectiveness of the proposed method is verified on the pantograph image caption dataset, and caption of the pantograph image is generated. © 2024, Beijing Paike Culture Commu. Co., Ltd.

关键词： Pantographs

来源：评论

学校读者我要写书评

暂无评论

A Distributionally Robust Optimization Method for Passenger Flow control Strategy and Train Scheduling on an Urban rail Transit Line

引用

Engineering 2022年第5期8卷 202-220页

作者： Yahan Lu Lixing Yang Kai Yang Ziyou Gao Housheng Zhou Fanting Meng Jianguo Qi State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China

Regular coronavirus disease 2019(COVID-19)epidemic prevention and control have raised new require-ments that necessitate operation-strategy innovation in urban rail *** alleviate increasingly seri-ous congestion and further reduce the risk of cross-infection,a novel two-stage distributionally robust optimization(DRO)model is explicitly constructed,in which the probability distribution of stochastic scenarios is only partially known in *** the proposed model,the mean-conditional value-at-risk(CVaR)criterion is employed to obtain a tradeoff between the expected number of waiting passen-gers and the risk of congestion on an urban rail transit *** relationship between the proposed DRO model and the traditional two-stage stochastic programming(SP)model is also ***,to overcome the obstacle of model solvability resulting from imprecise probability distributions,a discrepancy-based ambiguity set is used to transform the robust counterpart into its computationally tractable form.A hybrid algorithm that combines a local search algorithm with a mixed-integer linear programming(MILP)solver is developed to improve the computational efficiency of large-scale ***,a series of numerical examples with real-world operation data are executed to validate the pro-posed approaches.

关键词： Passenger flow control Train scheduling Distributionally robust optimization Stochastic and dynamic passenger demand Ambiguity set

来源：评论

学校读者我要写书评

暂无评论

Examining the Relationship Between Built Environment and Urban rail Transit Inter-Cluster OD Passenger Flow 6th

Examining the Relationship Between Built Environment and Urb...

引用

6th International Conference on Electrical Engineering and Information Technologies for rail Transportation, EITRT 2023

作者： Chen, Lidan Xu, Xinyue State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing100044 China

ISBN: (纸本)9789819993109

Research on the impact of built environment on Origin Destination (OD) passenger flow is essential for combining urban land planning and public transportation planning. However, the sparsity of inter-station OD makes the relationship between built environment and OD passenger flow not significant enough. To address this issue, this study proposes a clustering model based on passenger flow destination and station location. Firstly, the clustering is initialized based on the station location and station type. Then, a modular index of the road network clustering is established to optimize the clustering by considering the passenger flow destination, determine the optimal clustering, and classify it afterwards. Furthermore, considering the combination of different types of clusters, the GBRT model is used to study the relationship between different types of inter-cluster OD passenger flow and built environment. A case study in Beijing shows that the noise of the nonlinear effect of built environment on inter-cluster OD is smaller than that of the noise of the nonlinear effect of built environment on inter-station OD. This is because the aggregation of stations into clusters makes the regularity more significant, achieving better fitting results. © Beijing Paike Culture Commu. Co., Ltd. 2024.

关键词： Urban transportation

来源：评论

学校读者我要写书评

暂无评论

On the Polygonal Wear Evolution of Heavy-Haul Locomotive Wheels due to Wheel/rail Flexibility and Its Mitigation Measures

引用

Chinese Journal of Mechanical Engineering 2024年第1期37卷 40-61页

作者： Yunfan Yang Feifan Chai Pengfei Liu Liang Ling Kaiyun Wang Wanming Zhai State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China

Wheel polygonal wear can immensely worsen wheel/rail interactions and vibration performances of the train and track,and ultimately,lead to the shortening of service life of railway *** present,wheel/rail medium-or high-frequency frictional interactions are perceived as an essential reason of the high-order polygonal wear of railway wheels,which are potentially resulted by the flexible deformations of the train/track system or other external *** this work,the effect of wheel/rail flexibility on polygonal wear evolution of heavy-haul locomotive wheels is explored with aid of the long-term wheel polygonal wear evolution simulations,in which different flexible modeling of the heavy-haul wheel/rail coupled system is ***,the mitigation measures for the polygonal wear of heavy-haul locomotive wheels are *** results point out that the evolution of polygonal wear of heavy-haul locomotive wheels can be veritably simulated with consideration of the flexible effect of both wheelset and *** of mixed-line operation of heavy-haul trains and application of multicut wheel re-profiling can effectively reduce the development of wheel polygonal *** research can provide a deep-going understanding of polygonal wear evolution mechanism of heavy-haul locomotive wheels and its mitigation measures.

关键词： Heavy-haul locomotive Wheel polygonal wear Wheel/rail flexibility Long-term polygonal wear evolution Mitigation measures

来源：评论

学校读者我要写书评

暂无评论

A model predictive control strategy with switching cost functions for cooperative operation of trains

引用

Science China(Information Sciences) 2023年第7期66卷 224-236页

作者： Zixuan ZHANG Haifeng SONG Hongwei WANG Ling LIU Hairong DONG State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University School of Electronic and Information Engineering Beihang University Beijing National Railway Research and Design Institute of Signal and Communication

The cooperative control of trains is proposed as an innovative method for further improving operation efficiency. Model predictive control(MPC) has been widely discussed for multiple trains because it can handle the challenges posed by the cooperative control problem, such as complex constraints. In real situations, multiple objectives, such as comfort and safety, must be considered when controlling multiple trains with MPC, and the total objective may change during operation, affecting control performance. In this paper, a distributed structure based on switching cost function model predictive control(ScMPC) for multiple trains in a switching situation is given, where the cost functions of the train control problem change with the variable demand of cooperative operation. Furthermore, the feasibility of the proposed method and stability of the closed-loop system are proved to guarantee the stable operation of the controlled ***, the control method's effectiveness is verified. Three kinds of cost functions are given, and their control performance is compared to show the effect of different weights and the advantage of ScMPC.

关键词： cooperative control switching cost functions model predictive control automatic train operation railway train

来源：评论

学校读者我要写书评

暂无评论

Secrecy Capacity Maximization for IRS-Assisted High-Speed Train Communications

引用

IEEE Communications Letters 2025年第6期29卷 1290-1294页

作者： Li, Cuiran Luan, Jiahui Zhang, Zepeng Ai, Bo Wu, Hao Xie, Jianli Lanzhou Jiaotong University School of Electronic and Information Engineering Lanzhou730070 China Beijing Jiaotong University State Key Laboratory of Rail Traffic Control and Safety Beijing100044 China

In this letter, we propose an IRS-assisted MIMO communication system model in the presence of an eavesdropper (Eve). A distance-dependent Rician factor and real-time Doppler frequency offset (DFO) compensation mechanism are utilized to characterize highly time-varying wireless channels. The secrecy capacity optimization problem is formulated by jointly optimizing the transmit beamforming, artificial noise (AN) matrix, and IRS phase shifts, subject to transmit power and unit modulus constraints. To solve the non-convex problem, it is transformed into convex optimization problem by using weighted minimum mean square error (WMMSE) algorithm, and an alternating optimization strategy with coupled variables is used to derive the optimal solution. Simulation results show that the optimization algorithm proposed in this letter converges quickly and achieves higher secrecy capacity. © 1997-2012 IEEE.

关键词： Convex optimization

来源：评论

学校读者我要写书评

暂无评论

An mmWave Hybrid Beamforming for Steady High-Speed railway Communications 23

An mmWave Hybrid Beamforming for Steady High-Speed Railway C...

引用

6th International Conference on Electronics, Communications and control Engineering, ICECC 2023

作者： Liu, Yiru Ai, Bo Niu, Yong State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University China

ISBN: (纸本)9798400700002

In order to meet the demand for higher transmission rates of the future high-speed railway (HSR) wireless communication systems, millimeter wave (mmWave) communication and large-scale antenna arrays (LSAs) become promising technologies. By utilizing hybrid analog and digital beamforming architecture, the base station (BS) equipped with a LSA can form multiple narrow beams to transmit data streams to multiple mobile relays (MRs) equipped with antenna arrays. Usually, when the train is close to BS, the angular resolution between MRs is high. However, due to the straight shape of the track, the channels between different MRs are becoming highly correlated and multi-user interference can be detrimental to the multi-MRs performance when the train is far from the BS. Therefore, in this paper, we decouple the analog and digital domains of the hybrid BF. First, analog BF beams and a predefined codebook were designed considering the geometry of the straight-line shape track in the HSR scenario. Second, an adaptive analog BF selection is adopted to form appropriate beams when the train is far away from BS. Then mutual interference eliminating between MRs can be realized by digital precoding. The numerical results indicate that the proposed scheme can effectively solve the significant performance degradation of the multi-MR system during the train crossing the cell. © 2023 ACM.

关键词： railroads

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：