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A 1-bit electronically reconfigurable beam steerable metasurface reflectarray with multiple polarization manipulations
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作者 史琰 徐茜雅 +2 位作者 王少泽 魏文岳 武全伟 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期384-394,共11页
A 1-bit electronically controlled metasurface reflectarray is presented to achieve beam steering with multiple polarization manipulations. A metsurface unit cell loaded by two PIN diodes is designed. By switching the ... A 1-bit electronically controlled metasurface reflectarray is presented to achieve beam steering with multiple polarization manipulations. A metsurface unit cell loaded by two PIN diodes is designed. By switching the two PIN diodes between ON and OFF states, the isotropic and anisotropic reflections can be flexibly achieved. For either the isotropic reflection or the anisotropic reflection, the two operation states achieve the reflection coefficients with approximately equal magnitude and 180°out of phase, thus giving rise to the isotropic/anisotropic 1-bit metasurface unit cells. With the 1-bit unit cells, a 12-by-12 metasurface reflectarray is optimally designed and fabricated. Under either y-or x-polarized incident wave illumination, the reflectarray can achieve the co-polarized and cross-polarized beam scanning, respectively, with the peak gains of 20.08 d Bi and 17.26 d Bi within the scan range of about ±50°. With the right-handed circular polarization(RHCP) excitation, the left-handed circular polarization(LHCP) radiation with the peak gain of 16.98 d Bic can be achieved within the scan range of ±50°. Good agreement between the experimental results and the simulation results are observed for 2D beam steering and polarization manipulation capabilities. 展开更多
关键词 electronically controlled metasurface reflectarray beam steering polarization manipulation
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Experimental Study of Diesel-NG Dual Fuel Electronic System for F6L912Q Engine
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作者 张幽彤 王春发 +2 位作者 刘兴华 李铁栓 韩秀坤 《Journal of Beijing Institute of Technology》 EI CAS 2000年第4期397-402,共6页
In order to improve the diesel engine emission performance and convert the diesel engine to dual fuel engine, a dual fuel (diesel and compressed natural gas (CNG)) electronic system was developed, in which electromagn... In order to improve the diesel engine emission performance and convert the diesel engine to dual fuel engine, a dual fuel (diesel and compressed natural gas (CNG)) electronic system was developed, in which electromagnetic valves were used to control multi point natural gas injection. The system was designed for type F6L912Q diesel engine and the function of the system was testified on test cell. The test results showed that the system had great advantages in power ability and emission performance. The average CNG substitution at rated load was over 80%. The dual fuel system was practical. To adopt dual fuel system was a good way to improve the engine's emission performance. 展开更多
关键词 dual fuel electronic control development0
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The Research and Application of the Anti-Interference Techniques of Electronic Device in Power System 被引量:1
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作者 吴维宁 张文亮 +1 位作者 吴峡 李建建 《Electricity》 2001年第4期40-43,共4页
This paper presents the study and application of the electronic device anti-interference techniques underhigh voltage and/or heavy current electro-magnetic circumstance in power system.[
关键词 electric power system electronic measurement and/or control device anti-interference measures
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Speed Disturbance in the Diesel Engine Electronic Control System
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作者 刘兴华 张幽彤 《Journal of Beijing Institute of Technology》 EI CAS 2000年第4期387-390,共4页
In order to sample the speed signal of electronic diesel engine in real time and make the engine work reliable, the diesel engine control system's speed acquisition was studied and the problem of speed disturbance... In order to sample the speed signal of electronic diesel engine in real time and make the engine work reliable, the diesel engine control system's speed acquisition was studied and the problem of speed disturbance was solved. The control system was based on the 8?bit electronic control unit(ECU) system and the assembly language was used to design the software for controlling the engine fuel quantity and the turbocharger of the variable geometry turbine for the heavy duty diesel engine. By changing the timing method for speed acquisition, the problem of speed disturbance was solved and the reliability of the ECU was improved. 展开更多
关键词 diesel engine electronic control system speed disturbance
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Hierarchical Control of Ride Height System for Electronically Controlled Air Suspension Based on Variable Structure and Fuzzy Control Theory 被引量:14
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作者 XU Xing ZHOU Kongkang +2 位作者 ZOU Nannan JIANG Hong CUI Xiaoli 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第5期945-953,共9页
The current research of air suspension mainly focuses on the characteristics and design of the air spring. In fact, electronically controlled air suspension (ECAS) has excellent performance in flexible height adjust... The current research of air suspension mainly focuses on the characteristics and design of the air spring. In fact, electronically controlled air suspension (ECAS) has excellent performance in flexible height adjustment during different driving conditions. However, the nonlinearity of the ride height adjusting system and the uneven distribution of payload affect the control accuracy of ride height and the body attitude. Firstly, the three-point measurement system of three height sensors is used to establish the mathematical model of the ride height adjusting system. The decentralized control of ride height and the centralized control of body attitude are presented to design the ride height control system for ECAS. The exact feedback linearization method is adopted for the nonlinear mathematical model of the ride height system. Secondly, according to the hierarchical control theory, the variable structure control (VSC) technique is used to design a controller that is able to adjust the ride height for the quarter-vehicle anywhere, and each quarter-vehicle height control system is independent. Meanwhile, the three-point height signals obtained by three height sensors are tracked to calculate the body pitch and roll attitude over time, and then by calculating the deviation of pitch and roll and its rates, the height control correction is reassigned based on the fuzzy algorithm. Finally, to verify the effectiveness and performance of the proposed combined control strategy, a validating test of ride height control system with and without road disturbance is carried out. Testing results show that the height adjusting time of both lifting and lowering is over 5 s, and the pitch angle and the roll angle of body attitude are less than 0.15°. This research proposes a hierarchical control method that can guarantee the attitude stability, as well as satisfy the ride height tracking system. 展开更多
关键词 electronically controlled air suspension (ECAS) ride height body attitude hierarchical control
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Effect of powdered activated carbon on Chinese traditional medicine wastewater treatment in submerged membrane bioreactor with electronic control backwashing 被引量:8
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作者 LIU Xiao-lei REN Nan-qi MA Fang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第9期1037-1042,共6页
Chinese traditional medicine wastewater, rich in macromolecule and easy to foam in aerobic biodegradation such as Glycosides, was treated by two identical bench-scale aerobic submerged membrane bioreactors (SMBRs) o... Chinese traditional medicine wastewater, rich in macromolecule and easy to foam in aerobic biodegradation such as Glycosides, was treated by two identical bench-scale aerobic submerged membrane bioreactors (SMBRs) operated in parallel under the same feed, equipped with the same electronic control backwashing device. One was used as the control SMBR (CSMBR) while the other was dosed with powdered activated carbon (PAC) (PAC-amended SMBR, PSMBR). The backwashing interval was 5 min. One suction period was about 90 min by adjusting preestablished backwashing vacuum and pump frequency. The average flux of CSMBR during a steady periodic state of 24 d (576 h) was 5.87 L/h with average hydraulic residence time (HRT) of 5.97 h and that of PSMBR during a steady periodic state of 30 d (720 h) was 5.85 L/h with average HRT of 5.99 h. The average total chemical oxygen demand (COD) removal efficiency of CSMBR was 89.29% with average organic loading rate (OLR) at 4.16 kg COD/(m^3.d) while that of PSMBR was 89.79% with average OLR at 5.50 kg COD/(m^3.d). COD concentration in the effluent of both SMBRs achieved the second level of the general wastewater effluent standard GB8978-1996 for the raw medicine material industry (300 mg/L). Hence, SMBR with electronic control backwashing was a viable process for medium-strength Chinese traditional medicine wastewater treatment. Moreover, the increasing rates of preestablished backwashing vacuum, pump frequency, and vacuum and flux loss caused by mixed liquor in PSMBR all lagged compared to those in CSMBR; thus the actual operating time of the PSMBR system without membrane cleaning was extended by up to 1.25 times in contrast with the CSMBR system, and the average total COD removal efficiency of PSMBR was enhanced with higher average OLR. 展开更多
关键词 electronic control backwashing powdered activated carbon membrane bioreactor aerobic process wastewater treatment
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A Hybrid Approach to Modeling and Control of Vehicle Height for Electronically Controlled Air Suspension 被引量:8
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作者 SUN Xiaoqiang CAI Yingfeng +2 位作者 WANG Shaohua LIU Yanling CHEN Long 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第1期152-162,共11页
The control problems associated with vehicle height adjustment of electronically controlled air suspension (ECAS) still pose theoretical challenges for researchers, which manifest themselves in the publications on t... The control problems associated with vehicle height adjustment of electronically controlled air suspension (ECAS) still pose theoretical challenges for researchers, which manifest themselves in the publications on this subject over the last years. This paper deals with modeling and control of a vehicle height adjustment system for ECAS, which is an example of a hybrid dynamical system due to the coexistence and coupling of continuous variables and discrete events. A mixed logical dynamical (MLD) modeling approach is chosen for capturing enough details of the vehicle height adjustment process. The hybrid dynamic model is constructed on the basis of some assumptions and piecewise linear approximation for components nonlinearities. Then, the on-off statuses of solenoid valves and the piecewise approximation process are described by propositional logic, and the hybrid system is transformed into the set of linear mixed-integer equalities and inequalities, denoted as MLD model, automatically by HYSDEL. Using this model, a hybrid model predictive controller (HMPC) is tuned based on online mixed-integer quadratic optimization (MIQP). Two different scenarios are considered in the simulation, whose results verify the height adjustment effectiveness of the proposed approach. Explicit solutions of the controller are computed to control the vehicle height adjustment system in realtime using an offline multi-parametric programming technology (MPT), thus convert the controller into an equivalent explicit piecewise affine form. Finally, bench experiments for vehicle height lifting, holding and lowering procedures are conducted, which demonstrate that the HMPC can adjust the vehicle height by controlling the on-off statuses of solenoid valves directly. This research proposes a new modeling and control method for vehicle height adjustment of ECAS, which leads to a closed-loop system with favorable dynamical properties. 展开更多
关键词 electronically controlled air suspension vehicle height control hybrid system mixed logical dynamical model predictive control
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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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Electronically Controlling the System of Preheating Intake Air by Flame for Diesel Engine Cold-Start 被引量:2
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作者 杜巍 赵福堂 《Journal of Beijing Institute of Technology》 EI CAS 2003年第2期158-161,共4页
In order to improve the cold start performance of heavy duty diesel engine, electronically controlling the preheating of intake air by flame was researched. According to simulation and thermodynamic analysis about th... In order to improve the cold start performance of heavy duty diesel engine, electronically controlling the preheating of intake air by flame was researched. According to simulation and thermodynamic analysis about the partial working processes of the diesel engine, the amount of heat energy, enough to make the fuel self ignite at the end of compression process at different temperatures of coolant and intake air, was calculated. Several HY20 preheating plugs were used to heat up the intake air. Meanwhile, an electronic control system based on 8 bit micro controller unit (MCS 8031) was designed to automatically control the process of heating intake air. According to the various temperatures of coolant and ambient air, one plug or two plugs can automatically be selected to heat intake air. The demo experiment validated that the total system could operate successfully and achieve the scheduled function. 展开更多
关键词 diesel engine cold start preheating intake air electronically control
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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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Research and Development of a New Calibration Tool for Electronically Controlled Engine Based on KWP2000 被引量:1
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作者 冯静 王俊席 +1 位作者 钟军 卓斌 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第2期197-201,共5页
Today’s vehicles use electronic control units(ECU) to control engine/transmission, body and other amenities. All the vehicle performance depends on a lot of physical values and influence factors. This leads to a larg... Today’s vehicles use electronic control units(ECU) to control engine/transmission, body and other amenities. All the vehicle performance depends on a lot of physical values and influence factors. This leads to a large number of control and regulation parameters in the ECU software. The ultimate objective of calibration work is the optimum determination of these parameters. Qualitatively excellent results can only be achieved in a shorter time by using a highly efficient calibration system. This paper provided an overview of a new calibration tool based on KWP2000 and gave an example calibration with this tool. 展开更多
关键词 calibration tool KWP2000 electronically controlled engine
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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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Research on Development Trend of Automobile Electronic Technology 被引量:3
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作者 Zhigang Fu Xiaodong Ding 《International Journal of Technology Management》 2013年第2期20-22,共3页
Along with the popularization of artificial intelligence and information technology, the development of automobile industry have been closely combined with information technology, environmental protection and energy s... Along with the popularization of artificial intelligence and information technology, the development of automobile industry have been closely combined with information technology, environmental protection and energy saving ideas, promotion and application of electronic control technology, which development cycle becoming shorter and shorter. In this paper, through the analysis of the present application situation and development trend of the automobile electronic technology at present, in order to provide a theoretical reference for the future development of the automobile electronic control technology. 展开更多
关键词 AUTOMOBILE electronic control technology WIFI
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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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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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Optimizing the electronic spin state and delocalized electron of NiCo_(2)(OH)_(x)/MXene composite by interface engineering and plasma boosting oxygen evolution reaction
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作者 Jingyao Xu Xia Zhong +2 位作者 Xiaofeng Wu Ying Wang Shouhua Feng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第8期129-140,I0004,共13页
The electrocatalytic activity of transition-metal-based compounds is closely related to the electronic configuration.However,optimizing the surface electron spin state of catalysts remains a challenge.Here,we develope... The electrocatalytic activity of transition-metal-based compounds is closely related to the electronic configuration.However,optimizing the surface electron spin state of catalysts remains a challenge.Here,we developed a spin-state and delocalized electron regulation method to optimize oxygen evolution reaction(OER)performance by in-situ growth of NiCo_(2)(OH)_(x) using Oswald ripening and coordinating etching process on MXene and plasma treatment.X-ray absorption spectroscopy,magnetic tests and electron paramagnetic resonance reveal that the coupling of NiCo_(2)(OH)_(x) and MXene can induce remarkable spin-state transition of Co^(3+)and transition metal ions electron delocalization,plasma treatment further optimizes the 3 d orbital structure and delocalized electron density.The unique Jahn-Teller phenomenon can be brought by the intermediate spin state(t2 _(g)^(5) e_(g)^(1))of Co^(3+),which benefits from the partial electron occupied egorbitals.This distinct electron configuration(t2_(g)^(5) e_(g)^(1))with unpaired electrons leads to orbital degeneracy,that the adsorption free energy of intermediate species and conductivity were further optimized.The optimized electrocatalyst exhibits excellent OER activity with an overpotential of 268 m V at 10 m A cm^(-2).DFT calculations show that plasma treatment can effectively regulate the d-band center of TMs to optimize the adsorption and improve the OER activity.This approach could guide the rational design and discovery of electrocatalysts with ideal electron configurations in the future. 展开更多
关键词 Transition metal compounds electronic state control of surface/interface electron spin state Delocalized electron Electrocatalytic material
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Presentation on the Electronic Control System of Space Solar Telescope
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作者 Zhang Bin, Li Wei, Song Guofeng, Jin Shengzhen 1 (Beijing Astronomical Observatory, The Chinese Academy of Sciences, Beijing 100012, China) 2 (National Astronomical Observatories, Beijing 100012, China) 《天文研究与技术》 CSCD 1999年第S1期130-133,共4页
This paper gives the brief view of the electronic control system of SPACE SOLAR TELESCOPE (SST), especially the On Board Data Handling unit (OBDH) on the SST which control the operation of the instrument, acquire data... This paper gives the brief view of the electronic control system of SPACE SOLAR TELESCOPE (SST), especially the On Board Data Handling unit (OBDH) on the SST which control the operation of the instrument, acquire data and make data analysis and storage. In OBDH, the Scientific Data Unit (SDU) is a special unit that requires high speed computer. In this paper gives a brief comparison of two possible choices and discuss selection of electronic parts in the space environment. 展开更多
关键词 Presentation on the electronic Control System of Space Solar Telescope
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Extreme Dynamics on Electronic Cam Linear Drive
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作者 J. Cemohorsky 《Journal of Energy and Power Engineering》 2011年第12期1179-1186,共8页
One of the requirements for modem production machine is versatility and easy reconfiguration to produce new products. The production machines use fixed gearing and mechanical cams in history. The cams were used for sp... One of the requirements for modem production machine is versatility and easy reconfiguration to produce new products. The production machines use fixed gearing and mechanical cams in history. The cams were used for specific stokes and cam switches were used for commissioning of technological process. This solution has disadvantages in lower production speed and no flexibility of production. This article summaries practical steps for machine modernization and highlight practical problems in modernization of older production machine. The electronic cam with direct linear drive was used for traversal motion with high peak acceleration. This paper discusses cam stoke curve design, redesign and fitting. 展开更多
关键词 Motion control linear drive electronic cam direct drive.
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An Improvement in Power Quality and By-Product of the Run-Off River Micro Hydro Power Plant 被引量:1
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作者 Ignatius Riyadi Mardiyanto Jangkung Raharjo +2 位作者 Sri Utami Wahyu Budi Mursanto Agoeng Hardjatmo Rahardjo 《Energy Engineering》 EI 2023年第6期1295-1305,共11页
Utilization of Micro Hydro Power Plant at the Gunung Halu case study type run-off the river is a household use only in the afternoon,around 5 pm until bedtime at about 10 pm.Therefore,more than 75%of the energy is los... Utilization of Micro Hydro Power Plant at the Gunung Halu case study type run-off the river is a household use only in the afternoon,around 5 pm until bedtime at about 10 pm.Therefore,more than 75%of the energy is lost.This case study lost power which can be used as a by-product,such as for drying coffee beans.In this case study,a design was carried out to obtain by-products and improve power quality in the electrical system.In addition,they complain about the poor quality of power controlled by frequency using Triac-Based Electronic Dummy Load Control.The heat from the dummy load in the case study is used as a by-product.MHP with a minimum power of 20 kW,and the usage time of customer service is about 6 h.The energy for the by-products is about 360 kWh/day,and the power quality improved by using Triac-Based Electronic Load Control and Hysteresis Current Control for the active filter.As a result,the power factor is close to one,the generator current harmonics is less than 2%,and the voltage harmonics is less than 5%. 展开更多
关键词 electronics load controller triac-based hysteresis current control power quality micro-hydro power
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Electronic control seed-metering system for precision seeding maize based on fuzzy PID
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作者 Xiaoshun Zhao Hongpeng Zhao +3 位作者 Zehe Wang Jincai Li Huali Yu Qing Yan 《International Journal of Agricultural and Biological Engineering》 SCIE 2024年第4期217-226,共10页
Aiming at the problem of poor uniformity of maize sowing caused by ground wheel slip,an electronic control seed-metering system(ECSMS)for maize single seed precision sowing was designed and a mathematical model for mo... Aiming at the problem of poor uniformity of maize sowing caused by ground wheel slip,an electronic control seed-metering system(ECSMS)for maize single seed precision sowing was designed and a mathematical model for motor control of the ECSMS was determined.The PID parameters were set by Z-N method and fuzzy control.The fuzzy PID control design and Simulink simulation were completed by MATLAB,which reduced response time of the system by 0.23 s and improved the control accuracy.Experiments on the JPS-12 test bench show that the qualification index(QI)of maize seed-metering device with the ECSMS increases by 4.47%,the multiples index(MI)decreases by 1.96%,the miss index(MIX)decreases by 2.81%,and the coefficient of variation(CV)of qualified seed spacing decreases by 5.06%,and the sowing uniformity has been greatly improved.Test results of the soil-tank test bench show that the system has good sowing uniformity and stability.And the QI is 96.74%,the MI is 2.15%,the MIX is 1.10%,and the CV of qualified seed spacing is 16.24%.Under different setting seed spacing and different sowing operation speed,the change range of seeding quality index was within 10%.The results of field sowing test show that the QI was 84.21%,the MI was 2.63%,the MIX was 7.89%,and the CV of qualified seed spacing was 22.15%,which meet the requirements of JB/T 10293-2013‘Specification for single seed planters(precision planters)’and the agronomic requirements for maize precision sowing.The system runs stably and reliably in practical operation and has good operation performance. 展开更多
关键词 MAIZE seed-metering system electronic control precision sowing parameters tuning fuzzy PID control simulink simulation
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