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MULTIPLE ELECTRONIC CONTROL UNITS CALIBRATION SYSTEM BASED ON EXPLICIT CALIBRATION PROTOCOL AND J1939 PROTOCOL 被引量:3
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作者 ZHU Keqing XU Quankui YANG Lin ZHUO Bin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第1期42-46,共5页
The rising number of electronic control units (ECUs) in vehicles and the decreasing time to market have led to the need for advanced methods of calibration. A multi-ECU calibration system was developed based on the ... The rising number of electronic control units (ECUs) in vehicles and the decreasing time to market have led to the need for advanced methods of calibration. A multi-ECU calibration system was developed based on the explicit calibration protocol (XCP) and J1939 communication protocol to satisfy the need of calibrating multiple ECUs simultaneously. The messages in the controller area network (CAN) are defined in the J1939 protocol. Each CAN node can get its own calibration messages and information from other ECUs, and block other messages by qualifying the CAN messages with priority, source or destination address. The data field of the calibration message is designed with the XCP, with CAN acting as the transport layer. The calibration sessions are setup with the event-triggered XCP driver in the master node and the responding XCP driver in the slave nodes. Mirroring calibration variables from ROM to RAM enables the user to calibrate ECUs online. The application example shows that the multi-ECU calibration system can calibrate multiple ECUs simultaneously, and the main program can also accomplish its calculation and send commands to the actuators in time. By the multi-ECU calibration system, the calibration effort and time can be reduced and the variables in ECU can get a better match with the variables of other ECUs. 展开更多
关键词 electronic control unit (ECU) Calibration Explicit calibration protocol (XCP) J1939 communication protocol Controlled area network (CAN)
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Hardware-in-the-Loop Research on the Electronic Control Unit for Diesel Engines 被引量:1
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作者 王宇明 张付军 +1 位作者 王永庭 刘波澜 《Journal of Beijing Institute of Technology》 EI CAS 2009年第4期416-421,共6页
A hardware-in-the-loop simulating platform is developed to avoid designing defects caused by the complicated logical structure and multiple-functional buildup of the dectronic control unit(ECU)in modem diesel engine... A hardware-in-the-loop simulating platform is developed to avoid designing defects caused by the complicated logical structure and multiple-functional buildup of the dectronic control unit(ECU)in modem diesel engines, and to diminish potential damages on components or human exposure to dangers in R&D en- deavor. This plat-form consists of a computer installed with software Matlab/Simulink/RTW and dSPACE/ ControlDesk; a diesel engine ECU, and a dSPACE autobox which runs a real-time diesel engine model. A typical model of diesel engine with turbocharger and intercooler is presented. Based on this model our research is carried out with a real ECU to test its software control strategies. Results show that by using the diesel engine model downloaded inside, the hardware-in-the-loop platform can simulate diesel engine's working conditions and generate all kinds of sensor signals which ECU needs on a real-time basis. So the ECU control strategies can be validated and relevant parameters roughly calibrated. 展开更多
关键词 electronic control unit (ECU) diesel engine real-time model DSPACE hardware-in-the-loop simulation
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SIMULATION IN THERMAL DESIGN FOR ELECTRONIC CONTROL UNIT OF ELECTRONIC UNIT PUMP 被引量:1
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作者 XU Quankui ZHU Keqing ZHUO Bin MAO Xiaojian WANG Junxi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第5期1-7,共7页
The high working junction temperature of power component is the most common reason of its failure. So the thermal design is of vital importance in electronic control unit (ECU) design. By means of circuit simulation... The high working junction temperature of power component is the most common reason of its failure. So the thermal design is of vital importance in electronic control unit (ECU) design. By means of circuit simulation, the thermal design of ECU for electronic unit pump (EUP) fuel system is applied. The power dissipation model of each power component in the ECU is created and simulated. According to the analyses of simulation results, the factors which affect the power dissipation of components are analyzed. Then the ways for reducing the power dissipation of power components are carried out. The power dissipation of power components at different engine state is calculated and analyzed. The maximal power dissipation of each power component in all possible engine state is also carried out based on these simulations. A cooling system is designed based on these studies. The tests show that the maximum total power dissipation of ECU drops from 43.2 W to 33.84 W after these simulations and optimizations. These applications of simulations in thermal design of ECU can greatly increase the quality of the design, save the design cost and shorten design time 展开更多
关键词 Diesel engine electronic unit pump electronic control unit Circuit simulation Thermal design
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Measurement and analysis of cycle fuel injection quantity for electronic unit pump
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作者 张长岭 黄印玉 +1 位作者 王沛 张峥 《Journal of Measurement Science and Instrumentation》 CAS 2014年第4期74-78,共5页
The cycle fuel injection quantity is accurately measured for electronic unit pump (EUP) operating at high, middle and low speeds by using displacement method based on EFS instantaneous mono-injector qualifier. On th... The cycle fuel injection quantity is accurately measured for electronic unit pump (EUP) operating at high, middle and low speeds by using displacement method based on EFS instantaneous mono-injector qualifier. On the basis of the experi- mental data about fuel injection quantity and fuel pressure, the variation of inconsistency in fuel injection quantity of EUP and the influence factors in different operating conditions are concluded. The results show that the inconsistency is lowest in maximum torque condition, while on the start and maximum power conditions, it is higher. 展开更多
关键词 diesel engine fuel injection quantity electronic unit pump (EUP)
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MODEL-BASED DEVELOPMENT OF REAL-TIME SOFTWARE SYSTEM FOR ELECTRONIC UNIT PUMP SYSTEM 被引量:1
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作者 YU Shitao YANG Shiwei YANG Lin GONG Yuanming ZHUO Bin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第1期25-30,共6页
A real-time operating system (RTOS), also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-base... A real-time operating system (RTOS), also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-based task division method is introduced and the multi-task software architecture is built in the software system for electronic unit pump (EUP) system. The V-model software development process is used to control algorithm of each task. The simulation results of the hardware-in-the-loop simulation system (HILSS) and the engine experimental results show that the OS is an efficient real-time kernel, and can meet the real-time demands of EUP system; The built multi-task software system is real-time, determinate and reliable. V-model development is a good development process of control algorithms for EUP system, the control precision of control system can be ensured, and the development cycle and cost are also decreased. 展开更多
关键词 Real-time operating system (RTOS) Multi-task V-model development Hardware-in-the-loop simulation system(HILSS) electronic unit pump (EUP)
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ELECTRONIC CONTROL OF TURBINE POWER UNITS
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作者 Wang Daobo(Department of Science and Technology,NUAA 29 Yudao Street,Nanjing 210016,P.R.China) 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1994年第2期177-182,共6页
This paper is concerned with the development of electronic controller for turbine POwer units. In order to increase the reliability of the POwer unit, three control loops working in the hi-backup mode have been employ... This paper is concerned with the development of electronic controller for turbine POwer units. In order to increase the reliability of the POwer unit, three control loops working in the hi-backup mode have been employed. This control strategy is able to satisfy the demands of the application of the power unit to the aviation fields. 展开更多
关键词 electronic CONTROL POWER unitS AUXILIARY POWER supply TURBINE POWER unitS
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Electronic Unit Pump Diesel Engine Control Unit Design for Integrated Powertrain System
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作者 刘波澜 赵长禄 +1 位作者 张付军 黄英 《Journal of Beijing Institute of Technology》 EI CAS 2005年第1期71-74,共4页
The performance of the electronic unit pump (EUP) diesel engine is studied, it will be used in the integrated powertrain and its multi parameters are controllable. Both the theoretical analysis and experiment research... The performance of the electronic unit pump (EUP) diesel engine is studied, it will be used in the integrated powertrain and its multi parameters are controllable. Both the theoretical analysis and experiment research are taken. A control unit for the fuel quantity and timing in crankshaft domain is designed on this basis and the engine experiment test has been done. For the constant speed camshaft driving EUP system, the fuel quantity will increase as the supply angle goes up and injection timing has no effect. The control precision can reach 1°CA. The full injection timing MAP and engine peak performance curves are made successfully. 展开更多
关键词 electronic unit pump (EUP) diesel engine integrated powertrain electronic control unit
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Electronic Band Structure of Graphene Based on the Rectangular 4-Atom Unit Cell
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作者 Akira Suzuki Masashi Tanabe Shigeji Fujita 《Journal of Modern Physics》 2017年第4期607-621,共15页
The Wigner-Seitz unit cell (rhombus) for a honeycomb lattice fails to establish a k-vector in the 2D space, which is required for the Bloch electron dynamics. Phonon motion cannot be discussed in the triangular coordi... The Wigner-Seitz unit cell (rhombus) for a honeycomb lattice fails to establish a k-vector in the 2D space, which is required for the Bloch electron dynamics. Phonon motion cannot be discussed in the triangular coordinates, either. In this paper, we propose a rectangular 4-atom unit cell model, which allows us to discuss the electron and phonon (wave packets) motion in the k-space. The present paper discusses the band structure of graphene based on the rectangular 4-atom unit cell model to establish an appropriate k-vector for the Bloch electron dynamics. To obtain the band energy of a Bloch electron in graphene, we extend the tight-binding calculations for the Wigner-Seitz (2-atom unit cell) model of Reich et al. (Physical Review B, 66, Article ID: 035412 (2002)) to the rectangular 4-atom unit cell model. It is shown that the graphene band structure based on the rectangular 4-atom unit cell model reveals the same band structure of the graphene based on the Wigner-Seitz 2-atom unit cell model;the &pi;-band energy holds a linear dispersion (&epsilon;&minus;k ) relations near the Fermi energy (crossing points of the valence and the conduction bands) in the first Brillouin zone of the rectangular reciprocal lattice. We then confirm the suitability of the proposed rectangular (orthogonal) unit cell model for graphene in order to establish a 2D k-vector responsible for the Bloch electron (wave packet) dynamics in graphene. 展开更多
关键词 GRAPHENE RECTANGULAR 4-Atom unit Cell Model PRIMITIVE Orthogonal Basis VECTOR BLOCH electron (Wave Packet) Dynamics k-Vector Dirac Points Linear Dispersion Relation
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APPLICATION OF CIRCUIT SIMULATION IN HARDWARE DESIGN FOR ELECTRONIC CONTROL HIGH PRESSURE COMMON-RAIL FUEL SYSTEM OF DIESEL ENGINE 被引量:2
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作者 Tan Wenchun Yu Shitao Yang Lin Zhuo Bin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期613-616,共4页
By means of circuit simulation, hardware of electronic control unit (ECU) of high pressure common-rail electronic control fuel system for diesel engine is designed. According to the system requirements for hardware ... By means of circuit simulation, hardware of electronic control unit (ECU) of high pressure common-rail electronic control fuel system for diesel engine is designed. According to the system requirements for hardware of ECU, signal-processing circuit of variable reluctance (VR) sensor, filter circuit for input signal, high voltage power circuit and driver and protection circuit of solenoid are simulated as emphases. Difficulties of wide scope of VR sensor output signal, efficiency of high voltage power and reliable and swift driver of solenoid are solved. The results of simulation show that the hardware meets the requirement of the fuel system. At the same time, circuit simulation can greatly increase quality of the design, alleviate design labor and shorten design time. 展开更多
关键词 Diesel engine electronic control unit (ECU) Circuit simulation.
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The phase effect of electronic stopping power 被引量:1
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作者 Ma Zhong-Quan and Zheng Yu-Feng (Department of Physics, Xinjiang University, Urumqi 830046)(Department of Materials Science and Engineering, Tsinghua University, Beijing 100084) 《Nuclear Science and Techniques》 SCIE CAS CSCD 1998年第2期86-89,共4页
A corrective factor (E,ρ)≤1) dependent on ion energy and mass density of material for energy loss has been introduced into Bethe-Bloch formula, so that the energy deposition process of fast ion penetrating through t... A corrective factor (E,ρ)≤1) dependent on ion energy and mass density of material for energy loss has been introduced into Bethe-Bloch formula, so that the energy deposition process of fast ion penetrating through the allotropic solid films are well discussed with the two-component assumption. An analysis expression of electronic stopping power for different phase structures has been derived from the contribution of "valence" and "core" electrons. The two thirds of inelastic scattering arisen from valence electron was revealed by comparing the theoretical calculation and experimental results on both random and oriented lattice site. The corrective factor representative to the role of inner electrons increases with the projectile energy but decreases with mass density of solids. 展开更多
关键词 高能离子 非弹性碰撞 电子停止功率
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Effects of medically generated electromagnetic interference from medical devices on cardiac implantable electronic devices: A review
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作者 Walker Barmore Himax Patel +2 位作者 Cassandra Voong Caroline Tarallo Joe B Calkins Jr 《World Journal of Cardiology》 2022年第8期446-453,共8页
As cardiac implantable electronic devices(CIED)become more prevalent,it is important to acknowledge potential electromagnetic interference(EMI)from other sources,such as internal and external electronic devices and pr... As cardiac implantable electronic devices(CIED)become more prevalent,it is important to acknowledge potential electromagnetic interference(EMI)from other sources,such as internal and external electronic devices and procedures and its effect on these devices.EMI from other sources can potentially inhibit pacing and trigger shocks in permanent pacemakers(PPM)and implantable cardioverter defibrillators(ICD),respectively.This review analyzes potential EMI amongst CIED and left ventricular assist device,deep brain stimulators,spinal cord stimulators,transcutaneous electrical nerve stimulators,and throughout an array of procedures,such as endoscopy,bronchoscopy,and procedures involving electrocautery.Although there is evidence to support EMI from internal and external devices and during procedures,there is a lack of large multicenter studies,and,as a result,current management guidelines are based primarily on expert opinion and anecdotal experience.We aim to provide a general overview of PPM/ICD function,review documented EMI effect on these devices,and acknowledge current management of CIED interference. 展开更多
关键词 Electromagnetic interference Pacemaker Implantable cardioverter defibrillator Permanent pacemakers Cardiac implantable electronic devices Left ventricular assist device Endoscopy BRONCHOSCOPY ELECTROCAUTERY Capsule endoscopy Transcutaneous electrical nerve stimulators unit Spinal cord stimulator
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Non-fused medium bandgap electron acceptors for efficient organic photovoltaics 被引量:2
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作者 Tian-Jiao Wen Jiale Xiang +7 位作者 Nakul Jain Zhi-Xi Liu Zeng Chen Xinxin Xia Xinhui Lu Haiming Zhu Feng Gao Chang-Zhi Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第7期576-582,I0014,共8页
The cost-effective organic semiconductors are strongly needed in organic photovoltaics(OPVs). Herein,two medium bandgap(MBG) electron acceptors, TPT4F and TPT4Cl are developed via the new design of multi-noncovalent i... The cost-effective organic semiconductors are strongly needed in organic photovoltaics(OPVs). Herein,two medium bandgap(MBG) electron acceptors, TPT4F and TPT4Cl are developed via the new design of multi-noncovalent interaction assisted unfused core, flanked with two electron withdrawing end groups. These fullly non-fused MBG acceptors adapt the planar and rigid conformation in solid, therefore exhibiting the ordered face-on stacking and strong photoluminescence in films. As results, TPT4Cl^(-)based OPVs, upon blending with the PBDB-TF polymer donor, have achieved a power conversion efficiency of 10.16% with a low non-radiative loss of 0.27 e V, representing one of the best fullly non-fused medium bandgap acceptors with desirable cost-efficiency balance. 展开更多
关键词 Organic photovoltaic Medium bandgap electron withdrawing unit Non-covalent interaction
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Method for Converting Cone-Beam CT Values into Hounsfield Units for Radiation Treatment Planning
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作者 Tadanori Abe Kunihiko Tateoka +6 位作者 Yuichi Saito Takuya Nakazawa Masaki Yano Kensei Nakata Masanori Someya Masakazu Hori Koichi Sakata 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2017年第4期361-375,共15页
Cone-beam CT (CBCT) images acquired during radiation treatment can be used to recalculate the dose distribution as well as to confirm the treatment location. However, it is difficult to obtain the electron densities (... Cone-beam CT (CBCT) images acquired during radiation treatment can be used to recalculate the dose distribution as well as to confirm the treatment location. However, it is difficult to obtain the electron densities (EDs) necessary for dose calculation from CBCT images because of the effects of scatter contamination during CBCT image acquisition. This paper presents a mathematical method for converting the pixel values of CBCT images (CBCT values) into Hounsfield units (HUs) of radiation treatment simulation CT (simCT) images for use in radiation treatment planning. CBCT values are converted into HUs by matching the histograms of the CBCT values with the histograms of the HUs for each slice via linear scaling of the CBCT values. For prostate cancer and head-and-neck cancer patients, the EDs obtained from converted CBCT values (mCBCT values) show good agreement with the EDs obtained from HUs, within approximately 3.0%, and the dose calculated on the basis of CBCT images shows good agreement with the dose calculated on the basis of the simCT images, within approximately 2.0%. Because the CBCT values are converted for each slice, this conversion method can account for variation in the CBCT values associated with differences in body size, body shape, and inner tissue structures, as well as in longitudinally displaced positions from the isocenter, unlike conventional methods that use electron density phantoms. This method improves on conventional CBCT-ED conversion and shows considerable potential for improving the accuracy of radiation treatment planning using CBCT images. 展开更多
关键词 CONE-BEAM COMPUTED TOMOGRAPHY Hounsfield unit electron Density Ra-diation Treatment Planning
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Electron Dynamics in Solids
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作者 Shigeji Fujita James McNabb III Akira Suzuki 《Journal of Modern Physics》 2015年第6期733-748,共16页
Following Ashcroft and Mermin, the conduction electrons (“electrons” or “holes”) are assumed to move as wave packets. Dirac’s theorem states that the quantum wave packets representing massive particles always mov... Following Ashcroft and Mermin, the conduction electrons (“electrons” or “holes”) are assumed to move as wave packets. Dirac’s theorem states that the quantum wave packets representing massive particles always move, following the classical mechanical laws of motion. It is shown here that the conduction electron in an orthorhombic crystal moves classical mechanically if the primitive rectangular-box unit cell is chosen as the wave packet, the condition requiring that the particle density is constant within the cell. All crystal systems except the triclinic system have k-vectors and energy bands. Materials are conducting if the Fermi energy falls on the energy bands. Energy bands and gaps are calculated by using the Kronig-Penny model and its 3D extension. The metal-insulator transition in VO2 is a transition between conductors having three-dimensional and one-dimensional k-vectors. 展开更多
关键词 electron Dynamics Dirac’s THEOREM PRIMITIVE Rectangular-Box unit Cell Wave PACKET k-Vector
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Epidemiology of shoulder dislocations presenting to United States emergency departments:An updated ten-year study
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作者 Cole M Patrick Josiah Snowden +4 位作者 Michael D Eckhoff Clare K Green John P Scanaliato John C Dunn Nata Parnes 《World Journal of Orthopedics》 2023年第9期690-697,共8页
BACKGROUND Glenohumeral dislocation is a common injury that may predispose patients to chronic pain and instability.However,there is a paucity of current data available regarding the epidemiological trends of this inj... BACKGROUND Glenohumeral dislocation is a common injury that may predispose patients to chronic pain and instability.However,there is a paucity of current data available regarding the epidemiological trends of this injury.AIM To provide an updated,comparative assessment of the epidemiology of shoulder dislocations presenting to emergency departments in the United States.We also sought to analyze patient demographic risk factors and consumer products associated with dislocation events.METHODS Data were obtained from the national electronic injury surveillance system database for glenohumeral dislocations between 2012 and 2021.Incidence,age,sex,and injury characteristics were analyzed using weighted population statistics as well as incidence rates and 95%confidence intervals(CI).RESULTS In total,an estimated 773039 shoulder dislocations(CI:640598-905481)presented to emergency rooms across the United States during the study period.The annual incidence rate was 23.96 per 100000 persons and the average patient age at the time of injury was 37.1 years.Significantly more male patients sustained dislocations than female patients(537189,69.5%,vs 235834,30.5%,P<0.001).With regard to associated consumer products,sports and recreation equipment were involved in the highest proportion of incidents(44.31%),followed by home structures and construction materials(21.22%),and home furnishings,fixtures,and accessories(21.21%).Regarding product sub-groups,stairs,ramps,landings,floors was cited in the greatest number of cases(131745).CONCLUSION The national annual incidence rate of glenohumeral dislocations throughout the study period was approximately 23.92 per 100000 persons.Male adolescents sustained the highest proportion of dislocations,with a peak incidence in age group 15-20 years,predominantly secondary to participation in sporting and recreational activities.Conversely,women experienced a relatively consistent incidence of dislocation throughout their lifespan.After age 63,the incidence rate of dislocations in females was found to surpass that observed in males. 展开更多
关键词 Shoulder dislocation EPIDEMIOLOGY united States Emergency department Glenohumeral dislocation national electronic injury surveillance system
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基于动态模拟技术的混动车辆发动机电控单元检测系统设计 被引量:1
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作者 韩锐 《计算机测量与控制》 2024年第2期93-98,104,共7页
电控单元是混动车辆发动机中的重要组成部分,对于发动机以及混动车辆的行驶性能产生直接影响,为保证电控单元的运行正常,利用动态模拟技术,优化设计了混动车辆发动机电控单元检测系统;改装温度、转速等传感器设备以及信号处理器设备,调... 电控单元是混动车辆发动机中的重要组成部分,对于发动机以及混动车辆的行驶性能产生直接影响,为保证电控单元的运行正常,利用动态模拟技术,优化设计了混动车辆发动机电控单元检测系统;改装温度、转速等传感器设备以及信号处理器设备,调整系统电路的连接方式,实现硬件系统的优化;利用动态模拟技术模拟混动车辆发动机电控过程,结合不同故障类型下电控单元的运行特征,设置系统的检测标准;采集电控单元输出信号,从时域和频域两个方面提取信号特征,最终通过特征匹配确定电控单元状态、故障类型以及故障位置,实现系统的电控单元检测功能;综合混动车辆发动机的3种运行场景,通过系统测试实验得出结论:与传统检测系统相比,优化设计系统的漏检率和误检率分别降低了2.59%和2.05%,由此证明优化设计系统具有良好的检测功能。 展开更多
关键词 动态模拟技术 混动车辆 发动机电控单元 检测系统
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美国电子资源相关标准规范研究
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作者 胡大琴 《图书馆》 CSSCI 2024年第4期33-39,共7页
近年来,数字阅读在全民阅读中所占的比重越来越大,图书馆提供更加丰富的数字资源服务已是大势所趋。然而,我国公共数字文化建设还存在平台、管理、资源方面互联互通程度不高等问题,要建设优质的电子资源管理平台,需要完善的标准作为支... 近年来,数字阅读在全民阅读中所占的比重越来越大,图书馆提供更加丰富的数字资源服务已是大势所趋。然而,我国公共数字文化建设还存在平台、管理、资源方面互联互通程度不高等问题,要建设优质的电子资源管理平台,需要完善的标准作为支撑。文章通过调研电子资源相关标准较为完备的美国,以《电子资源管理系统未来标准需求白皮书》为主要参考依据,将世界先行执行组织作为标杆,对白皮书发布后重要标准的变化进行分析,为完善我国相关标准规范提供借鉴,同时为电子资源产业行业的健康发展提供支持。 展开更多
关键词 电子资源 图书馆服务平台 美国 标准规范
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跟构网换流器并联的海上DRU低频交流送出方案
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作者 程志江 姜明皓 +3 位作者 杨天翔 杨志千 艾斯卡尔 郭锐 《太阳能学报》 EI CAS CSCD 北大核心 2024年第9期493-500,共8页
基于不可控整流单元(DRU)的风电低频交流送出系统不具备功率返送的能力,需采用构网型换流器实现海上风电场的自组网。同时考虑传统跟网型换流器所具备的快速功率响应能力对海上风力发电带来的正面影响,以六相永磁同步电机构成的风电机... 基于不可控整流单元(DRU)的风电低频交流送出系统不具备功率返送的能力,需采用构网型换流器实现海上风电场的自组网。同时考虑传统跟网型换流器所具备的快速功率响应能力对海上风力发电带来的正面影响,以六相永磁同步电机构成的风电机组作为研究对象,阐明在风电机组内,采用两种控制策略的换流器并联经DRU低频交流送出系统的拓扑结构和运行特性。分别设计风电机组网侧换流器的构网型控制策略与跟网型控制策略,并在此基础上探讨两组网侧换流器之间的功率不平衡问题,进一步设计环流抑制策略,实现风电功率经DRU送出。通过搭建Simulink仿真模型和RT-LAB半实物仿真系统验证方案的可行性。 展开更多
关键词 海上风电 电力输送 电力电子 二极管整流单元 半实物仿真
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电学计量中的量子标准与自然常数
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作者 刘民 屠治国 潘攀 《计测技术》 2024年第1期23-29,共7页
介绍了库仑定律和安培定律在电学单位制中发挥的作用,依据机械功率与电功率等效的原理,选择电流单位安培(A)作为基本物理单位,并介绍了实用单位制和电学实物计量标准。阐述了三种电学计量的量子标准原理和溯源到自然常数的途径,分析了... 介绍了库仑定律和安培定律在电学单位制中发挥的作用,依据机械功率与电功率等效的原理,选择电流单位安培(A)作为基本物理单位,并介绍了实用单位制和电学实物计量标准。阐述了三种电学计量的量子标准原理和溯源到自然常数的途径,分析了真空磁导率在安培定律公式中发挥的作用,探讨了电学量子三角形与欧姆定律兼容的问题。指出基本电荷量常数不是简单地从约瑟夫森常数K_(J-90)和冯·克里青常数R_(H-90)推导而来,而是由精细结构常数公式计算出来的,能量守恒原理是单位制中的第一性原理,是力学和电学计量单位的纽带。提出量子点之间的位移电流对单电子隧道泵有一定的影响,真空磁导率不再是理想的常数,真空磁导率的变化将成为后来理论界研究的重点。 展开更多
关键词 国际单位制 约瑟夫森电压标准 量子化霍尔电阻标准 单电子隧道泵 基本电荷量常数 普朗克常数 精细结构常数 真空磁导率
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基于电子式电压互感器边界特性分析的35 kV配网输电线路单端暂态量保护方案及其整定 被引量:2
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作者 吴宇奇 黎钊 +4 位作者 肖澍昱 黄梓欣 李正天 魏繁荣 林湘宁 《中国电机工程学报》 EI CSCD 北大核心 2024年第12期4666-4681,I0007,共17页
随着分布式电源广泛接入配电网,传统三段式电流保护方案的性能严重劣化。单端暂态量边界保护由于具备不依赖电源特性等突出优势,有望成为改善主动配电网保护配置性能的有效方案,但其需依附于线路边界强健的滤波作用。为此,该文研究发现... 随着分布式电源广泛接入配电网,传统三段式电流保护方案的性能严重劣化。单端暂态量边界保护由于具备不依赖电源特性等突出优势,有望成为改善主动配电网保护配置性能的有效方案,但其需依附于线路边界强健的滤波作用。为此,该文研究发现,可利用智能变电站和智能开闭所中电子式电压互感器、金属氧化物避雷器与其余设备杂散电容共同作为线路边界,其优异的高频滤波作用能够为暂态量保护方案的设计奠定基础;其次,利用区内外故障时电压行波高频频带能量差异构造保护判据,并基于整定门槛与动作时序的合理配合形成单端暂态量阶段式保护方案;最后,基于PSCAD仿真平台验证所提方案的有效性、灵敏性与可靠性,其可与电流保护方案协同互济以强化主动配电网继电保护方案的动作性能。 展开更多
关键词 配电线路 单端暂态量保护 线路边界 电子式电压互感器 金属氧化物避雷器 智能变电站
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