IET Electrical Systems in Transportation最新文献_第2页

Autonomous Energy Management Strategy in the Intermediate Circuit of an Electric Hybrid Drive with a Supercapacitor 带超级电容器的混合动力电动汽车中间电路的自主能量管理策略

IF 1.9 4区工程技术

IET Electrical Systems in Transportation Pub Date : 2024-09-06 DOI: 10.1049/2024/3459997

Milan Vacarda

{"title":"Autonomous Energy Management Strategy in the Intermediate Circuit of an Electric Hybrid Drive with a Supercapacitor","authors":"Milan Vacarda","doi":"10.1049/2024/3459997","DOIUrl":"https://doi.org/10.1049/2024/3459997","url":null,"abstract":"<div>\u0000 <p>Hybrid electric vehicles (HEVs) require the design of an energy management strategy (EMS). Many EMS are solved using different types of deterministic rules (rule-based (RB)) or optimization-based (OB) methods. The disadvantage of these strategies is that the primary energy flows in the drive are only solved “ex post,” when in principle, they cannot bring a substantial increase in energy recovery. A little-studied HEV traction drive topology is an internal combustion engine (ICE), supercapacitor (SC), traction motor (TM), and electric power divider (EPS) assembly. The original EMS method implemented in this assembly is based on the control of energy flows at the physical level in the DC link node. Changes in the power of the TM, under the condition of zero summation of currents in the DC link, will spontaneously induce energy spillover from and to the supercapacitor. The state of energy (SOE) in the supercapacitor can then be maintained by the balanced power of the ICE. This makes it possible to achieve a reduction in accelerations of approximately 30%. In principle, the presented EMS makes it possible to absorb all the kinetic and potential energy of negative driving resistances, thereby significantly reducing vehicle consumption. The strategy does not even require knowledge of the driving profile and bypasses complicated optimization algorithms. When validating the EMS method on an experimental test bench by implementing the driving cycle into real prototype components of the HEV physical model, a recovery rate of 14% was achieved, but the potential is up to twice that.</p>\u0000 </div>","PeriodicalId":48518,"journal":{"name":"IET Electrical Systems in Transportation","volume":"2024 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/2024/3459997","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142152213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Parameter Optimization of Balise Circuit Based on Fusion of BNN and Genetic Algorithm 基于 BNN 和遗传算法融合的平衡电路参数优化

IF 1.9 4区工程技术

IET Electrical Systems in Transportation Pub Date : 2024-07-26 DOI: 10.1049/2024/3963166

Zhengjiao Li, Zishuo Zhao, Jiang Liu, Zhongqi Zhang, Baigen Cai

{"title":"Parameter Optimization of Balise Circuit Based on Fusion of BNN and Genetic Algorithm","authors":"Zhengjiao Li, Zishuo Zhao, Jiang Liu, Zhongqi Zhang, Baigen Cai","doi":"10.1049/2024/3963166","DOIUrl":"https://doi.org/10.1049/2024/3963166","url":null,"abstract":"<div>\u0000 <p>The optimization of the parameters of the components related to the radio frequency (RF) transmission circuit of the balise can keep the balise working normally under low power consumption and increase the reliability and stability of the high-speed railway vehicle-ground communication. However, the circuit has high complexity, many parameters need to be considered in optimization, and the constraint relationship is complex. Optimizing a single objective is very difficult and time-consuming. Therefore, this paper proposes a ground transponder design and optimization method based on deep learning. Firstly, the functional modules of the balise RF circuit are decomposed, and the influencing factors of circuit start-up conditions and load quality factors are analysed, and the component parameters that need to be optimized are extracted as decision variables. The objective function of the model is established from the perspective of circuit cost and static power consumption, and a multi-objective optimization model is established through its overall circuit scheme. Finally, in order to reduce the time cost, the multi-objective optimization model is processed by the fusion of neural network and genetic algorithm. Among them, the experimental results show that the optimization effect of Bayesian neural network (BNN) is the most significant, and the static power consumption and cost of the circuit can be reduced by 55% and 42%, respectively, with less time overhead.</p>\u0000 </div>","PeriodicalId":48518,"journal":{"name":"IET Electrical Systems in Transportation","volume":"2024 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/2024/3963166","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141967104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Energy Management Strategy Based on Model Predictive Control-Differential Evolution for Hybrid Energy Storage System in Electric Vehicles 基于模型预测控制-差分进化的电动汽车混合储能系统能源管理策略

IF 2.3 4区工程技术

IET Electrical Systems in Transportation Pub Date : 2024-06-14 DOI: 10.1049/2024/8840942

Yaohua Tang, Junchao Xie, Yongpeng Shen, Songnan Sun, Yuanfeng Li

引用次数: 0

The Impact of Wheel Flat on Traction Drive System of Electric Locomotives 车轮扁平对电力机车牵引传动系统的影响

IF 2.3 4区工程技术

IET Electrical Systems in Transportation Pub Date : 2024-04-16 DOI: 10.1049/2024/2889871

Like Pan, Bing Lu, Caizhi Yang, Liming Chen, Yang Song, Tao Zhang

{"title":"The Impact of Wheel Flat on Traction Drive System of Electric Locomotives","authors":"Like Pan, Bing Lu, Caizhi Yang, Liming Chen, Yang Song, Tao Zhang","doi":"10.1049/2024/2889871","DOIUrl":"10.1049/2024/2889871","url":null,"abstract":"<div>\u0000 <p>Wheel flat can seriously affect the wheel–rail contact performance and cause impact vibrations, which significantly threaten the safe operation of railway vehicles. It is crucial to accurately assess the effects of wheel flats on the wheel–rail contact performance and the vibration impact on the traction drive system. However, studies related to wheel flats have focused on the mechanical part and have yet to fully consider the electrical and mechanical parts of the entire traction drive system. Therefore, this paper first builds an electromechanical coupling model based on the electric traction drive system and the locomotive-track coupling dynamics model. Then, based on this model, the impact of the wheel flat on the electrical and mechanical parts of the traction drive system under different flat lengths, different flat depths, and different vehicle speeds was analyzed. The results indicate that with the increasing depth of the flat spot, the wheel–rail dynamic response, motor rotor speed, and motor torque exhibit more significant fluctuations. Additionally, as the locomotive speed increases, the impact of the flat on the wheel–rail contact performance intensifies. Wheel flats can excite the 1st bending mode of the wheelset, resulting in vibration shocks at 90 Hz.</p>\u0000 </div>","PeriodicalId":48518,"journal":{"name":"IET Electrical Systems in Transportation","volume":"2024 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/2024/2889871","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140697174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dual Independent Rotor Axial Flux Induction Motor for Electric Vehicle Applications 用于电动汽车应用的双独立转子轴向磁通感应电机

IF 2.3 4区工程技术

IET Electrical Systems in Transportation Pub Date : 2024-04-04 DOI: 10.1049/2024/5594289

Alireza Hesari, Ahmad Darabi, Fazel Pourmirzaei Deylami

{"title":"Dual Independent Rotor Axial Flux Induction Motor for Electric Vehicle Applications","authors":"Alireza Hesari, Ahmad Darabi, Fazel Pourmirzaei Deylami","doi":"10.1049/2024/5594289","DOIUrl":"10.1049/2024/5594289","url":null,"abstract":"<div>\u0000 <p>This article proposes a dual independent rotor axial flux induction motor (DIR-AFIM) with two degrees of freedom as a propulsion motor for an electric vehicle (EV). The performance of this motor in different operating conditions of the vehicle is discussed and investigated. This motor has two rotors that are mechanically independent of each other, providing driving force for the EV separately and enabling the removal of any mechanical or electrical differential. The propulsion motor can play the role of differential and also reduce the cost and complexity of the entire propulsion system in some extent. The finite element modeling of the proposed motor has been performed and the performance characteristics have been evaluated in three operating scenarios: flat path, sloped path, and turning path, taking into account the dynamics of the vehicle. Additionally, the accuracy of the simulations and modeling has been confirmed by performing some practical tests on the prototype machine. The results show that the simulations and measurements are in good agreement and the proposed propulsion system can be a suitable option for lightweight electric vehicles.</p>\u0000 </div>","PeriodicalId":48518,"journal":{"name":"IET Electrical Systems in Transportation","volume":"2024 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/2024/5594289","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140744299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Inner Resonance and Outer Current Based Control Strategy for Inductive Power Transfer System Used in Wireless Charging for Electric Vehicles 用于电动汽车无线充电的感应式功率传输系统的基于内谐振和外电流的控制策略

IF 2.3 4区工程技术

IET Electrical Systems in Transportation Pub Date : 2024-03-06 DOI: 10.1049/2024/6668174

Sooraj Varikkottil, Febin Daya John Lionel, Mohan Krishna Srinivasan, Thinagaran Perumal, Albert Alexander Stonier, Geno Peter, Balachennaiah Pagidi, Vivekananda Ganji

{"title":"Inner Resonance and Outer Current Based Control Strategy for Inductive Power Transfer System Used in Wireless Charging for Electric Vehicles","authors":"Sooraj Varikkottil, Febin Daya John Lionel, Mohan Krishna Srinivasan, Thinagaran Perumal, Albert Alexander Stonier, Geno Peter, Balachennaiah Pagidi, Vivekananda Ganji","doi":"10.1049/2024/6668174","DOIUrl":"10.1049/2024/6668174","url":null,"abstract":"<div>\u0000 <p>The wireless charging for electric vehicle is getting popular due to the absence of sophisticated cable connection and associated issues with the actuators in field for connected charging. The major challenges in inductive power transfer (IPT) systems are the control of the resonance converter and synchronisation in communications with the vehicle and power supply. In IPT system, the dynamic nature of load as well as system demands extra care for the existing charging architectures. This work proposes a unique control algorithm to charge the Li-ion battery under coupling coefficient and load variations. The developed control algorithm is validated in MATLAB simscape platform. Further, the control logic is validated using the Texas C2000 Delfino controller in 1 kW IPT system. The developed control logic would ensure proper frequency of operation as well as the constant voltage and constant current control.</p>\u0000 </div>","PeriodicalId":48518,"journal":{"name":"IET Electrical Systems in Transportation","volume":"2024 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/2024/6668174","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140261411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Performance Enhancement of Flux Switching Motor for Electric Vehicle Applications: An Overview 用于电动汽车应用的磁通开关电机性能提升：概述

IF 2.3 4区工程技术

IET Electrical Systems in Transportation Pub Date : 2024-01-13 DOI: 10.1049/2024/9071667

Jawad Faiz, Majid Maktobian

{"title":"Performance Enhancement of Flux Switching Motor for Electric Vehicle Applications: An Overview","authors":"Jawad Faiz, Majid Maktobian","doi":"10.1049/2024/9071667","DOIUrl":"10.1049/2024/9071667","url":null,"abstract":"<div>\u0000 <p>As the reduction of greenhouse gas emissions becomes crucial, electric vehicles (EVs) are expected to enter the market extensively in the coming years. The efficiency of the electrical motor used in EVs plays a significant role in their overall performance. This paper explores the flux switching motor (FSM) and its applications in EVs. The FSM is compared to other electrical motors, highlighting its potential as a suitable choice for EV traction. Various configurations and techniques are reviewed to enhance the performance of FSMs, including magnetic materials, torque ripple alleviation, and magnetic flux weakening. The advantages and disadvantages of these methods are discussed, providing valuable insights for designing FSMs for EVs. Generally, EV traction requires high torque density and high power density electrical motor. To achieve these goals, high electric and magnetic loading must be considered in design stage of the motor. Application of the FSM may be one of the appropriate option. For many reasons, three-phase FSM is preferred. Considering the base speed of machine in the EV and high electric loading, the FSM with 12 stator teeth and 10 rotor teeth may be the most appropriate choice in which the stator core is oriented and rotor core is nonoriented iron. To enhance the torque density and applied flux weakening method, combination of Nd and Al–Ni–Co magnets is preferred.</p>\u0000 </div>","PeriodicalId":48518,"journal":{"name":"IET Electrical Systems in Transportation","volume":"2024 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/2024/9071667","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139531531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Single-Stage Isolated Battery Charger Using Nonbridged Positive Cuk Converter Configuration 使用非桥接正极 Cuk 转换器配置的单级隔离电池充电器

IF 1.9 4区工程技术

IET Electrical Systems in Transportation Pub Date : 2023-12-20 DOI: 10.1049/2023/6650034

Tanmay Shukla, N. P. Patidar, Apsara Adhikari

{"title":"A Single-Stage Isolated Battery Charger Using Nonbridged Positive Cuk Converter Configuration","authors":"Tanmay Shukla, N. P. Patidar, Apsara Adhikari","doi":"10.1049/2023/6650034","DOIUrl":"10.1049/2023/6650034","url":null,"abstract":"<div>\u0000 <p>This article presents a nonbridged isolated positive Cuk (NB-IPCuk) converter-based single-stage battery charging system (SSBCS). The architecture of the suggested charger ensures the intrinsic advantage of power quality improvement in discontinuous current conduction (DCC) mode at the supply mains. The suggested NB-IPCuk converter scheme has fewer components than other bridgeless/nonbridged Cuk converter schemes. This is because the NB-IPCuk converter is a partial integration of two Cuk converters. The usage of the Cuk converter garnishes the system with input and output inductances, which lessens supply current harmonic distortion and, thus supply terminal low pass filter requirement is eradicated. The advantages of the NB-IPCuk converter are the eradication of one inductor and multiple diodes (two back-feeding diodes), which are generally used in NB converter configurations. In place of two separate inductors, the NB-IPCuk converter uses a single secondary side output inductor. The usage of BL configuration of NB-IPCuk converter eradicates the bridge rectifier (BR) stage, and thus, the BR-associated losses also got eradicated. The NB-IPCuk converter also garnishes the system with electrical isolation which adds to the safety standards of the system. DCC mode operation of the NB-IPCuk converter is used in the present work. DCC mode requires lesser sensors in comparison to continuous current conduction mode. The abovementioned benefits of the NB-IPCuk converter make the SSBCS system cheaper, compact, and more efficient. The detailed stability analysis (Bode diagram and pole-zero map) and mathematics for the NB-IPCuk converter are also included in the paper. The prototype and MATLAB/Simulink model of NB-IPCuk converter-based SSBCS system with DCC mode control has been built, and results of both prototype and MATLAB/Simulink are deployed to verify SSBCS system’s performance during dynamic and steady-state conditions.</p>\u0000 </div>","PeriodicalId":48518,"journal":{"name":"IET Electrical Systems in Transportation","volume":"2023 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/2023/6650034","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139168823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of Wind-Powered Smart Transition Electric Vehicle Charging Station 开发风力发电智能过渡电动汽车充电站

IF 1.9 4区工程技术

IET Electrical Systems in Transportation Pub Date : 2023-11-27 DOI: 10.1049/2023/9593445

Soumya Mohanty, Swagat Pati, Sanjeeb Kumar Kar, Aymen Flah, Claude Ziad El-Bayeh, A. S. Veerendra

{"title":"Development of Wind-Powered Smart Transition Electric Vehicle Charging Station","authors":"Soumya Mohanty, Swagat Pati, Sanjeeb Kumar Kar, Aymen Flah, Claude Ziad El-Bayeh, A. S. Veerendra","doi":"10.1049/2023/9593445","DOIUrl":"10.1049/2023/9593445","url":null,"abstract":"<div>\u0000 <p>The power industry is embracing green energy solutions to meet growing demand along with advancement in its technological innovations. Among the myriad innovations, electric spring stands out as a cutting-edge technology, embracing the concept of smart load to intelligently manage power systems. Concurrently, the emergence of electric vehicles (EVs) has paved the way for a new branch of power networks in the transport system. Ingeniously combining these two trends, a smart charging mechanism has been developed through an EV charging station within an isolated microgrid having a wind energy conversion system as the lone and primary source. To ensure optimal performance and stability, a sophisticated smoothening band charge controller has been developed. This controller enables seamless transitions between fast and slow charging modes, effectively curbing noncritical voltage fluctuations beyond permissible thresholds. In order to demonstrate the superior efficacy of the smoothening band charge controller, a comprehensive comparative study was conducted, analyzing its performance against rapid transition controllers. The results highlight the remarkable advantages of the smoothening band approach, further solidifying its significance in future smart charging systems. To validate the proposed system, rigorous testing was carried out using the state-of-the-art OPAL-RT 4510 real-time simulator. The successful validation marks a pivotal step toward the widespread adoption of this innovative and environmentally conscious approach in the power industry.</p>\u0000 </div>","PeriodicalId":48518,"journal":{"name":"IET Electrical Systems in Transportation","volume":"2023 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/2023/9593445","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139229610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multiobjective Electric Vehicle Charging Network Planning Considering Chance-Constraint on the Travel Distance for Charging 多目标电动汽车充电网络规划，考虑充电行程的偶然性约束

IF 1.9 4区工程技术

IET Electrical Systems in Transportation Pub Date : 2023-11-17 DOI: 10.1049/2023/6690544

Yunxiang Guo, Xinsong Zhang, Daxiang Li, Chenghong Gu, Cheng Lu, Ting Ji, Yue Wang

{"title":"Multiobjective Electric Vehicle Charging Network Planning Considering Chance-Constraint on the Travel Distance for Charging","authors":"Yunxiang Guo, Xinsong Zhang, Daxiang Li, Chenghong Gu, Cheng Lu, Ting Ji, Yue Wang","doi":"10.1049/2023/6690544","DOIUrl":"10.1049/2023/6690544","url":null,"abstract":"<div>\u0000 <p>Electric vehicle charging stations (EVCSs) are important infrastructures to support sustainable development of electric vehicles (EVs), by providing convenient, rapid charging services. Therefore, the planning of electric vehicle charging network (EVCN) has attracted wide interest from both industry and academia. In this paper, a multiobjective planning model for EVCN is developed, where a fixed number of EVCSs are planned in the traffic network (TN) to achieve two objectives, i.e., minimizing both average travel distance for charging (TDfC) of EVs and investment costs of EVCN. According to the random characteristics of EVs’ TDfC, its constraint is presented as a chance constraint in the developed EVCN planning model. The nondominated sorting genetic Algorithm II with the constraint domination principle (NSGA-II-CDP) is customized to solve the developed multiobjective EVCN planning model, by designing a special coding scheme, a crossover operator, and a mutation operator. Then, a maximum gradient principle of investment revenue is designed to select the optimal planning strategy from the Pareto-optimal solution set, when taking the investment return ratio as primary consideration. A 25-node TN is used to justify the effectiveness of the developed methodology.</p>\u0000 </div>","PeriodicalId":48518,"journal":{"name":"IET Electrical Systems in Transportation","volume":"2023 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/2023/6690544","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139265914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0