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Development of electric power cooperation in Northeast Asia
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作者 Nikolai Voropai Sergei Podkovalnikov +1 位作者 Lyudmila Chudinova Ksenia Letova (Kushkina) 《全球能源互联网:英文版》 2019年第1期1-6,共6页
The development of interstate electric ties ISETs and grids(ISGs) is a global process;recently, countries of Northeast Asia(NEA) that were previously very poorly connected have started to study the possibility of cons... The development of interstate electric ties ISETs and grids(ISGs) is a global process;recently, countries of Northeast Asia(NEA) that were previously very poorly connected have started to study the possibility of constructing ISETs and ISGs. This paper describes the current state of the interstate transmissions in the NEA region, considering the prospective projects of ISETs in NEA. The results of the system optimization study on prospective NEA ISGs are provided. The proposals on the development of electric power cooperation in NEA are formulated. 展开更多
关键词 In teg RATI on ELECTRIC POWER industry Interstate ELECTRIC TIES POWER grids NORTHEAST Asia Economic EFFECTIVENESS
Applications of Serial-Parallel Compensated Resonant Topology in Wireless Charger System Used in Electric Vehicles 预览
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作者 付永升 雷鸣 +1 位作者 高磊磊 周刚 《东华大学学报:英文版》 EI CAS 2019年第1期15-22,共8页
There are lots of factors that can influence the wireless charging efficiency in practice, such as misalignment and air-gap difference, which can also change all the charging parameters. To figure out the relationship... There are lots of factors that can influence the wireless charging efficiency in practice, such as misalignment and air-gap difference, which can also change all the charging parameters. To figure out the relationship between those facts and system, this paper presents a serial-parallel compensated(SPC) topology for electric vehicle/plug-in hybrid electric vehicle(EV/PHEV) wireless charger and provides all the parameters changing with corresponding curves. An ANSYS model is built to extract the coupling coefficient of coils. When the system is works at constant output power, the scan frequency process can be applied to wireless power transfer(WPT) and get the resonant frequency. In this way, it could determine the best frequency for system to achieve zero voltage switching status and force the system to hit the maximum transmission efficiency. Then frequency tracking control(FTC) is used to obtain the highest system efficiency. In the paper, the designed system is rated at 500 W with 15 cm air-gap, the overall efficiency is 92%. At the end, the paper also gives the consideration on how to improve the system efficiency. 展开更多
关键词 wireless power transfer(WPT) zero voltage switching frequency tracking control(FTC) ELECTRIC vehicle/plug-in hybrid ELECTRIC vehicle(EV/PHEV)
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Using Augmented Reality Techniques to Simulate Training and Assistance in Electric Power 预览
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作者 Zifeng Tang Jiyao Deng +4 位作者 Hao Gao Jiageng Song Qinlun Li Peixin Zhang Minghui Sun 《国际计算机前沿大会会议论文集》 2019年第2期587-589,共3页
In combination with the augmented reality (AR) technology and Hololens device, an electric power work assist system is developed to provide a more realistic and convenient training experience for electric power traini... In combination with the augmented reality (AR) technology and Hololens device, an electric power work assist system is developed to provide a more realistic and convenient training experience for electric power training. The training effect was improved, and help guidance information was provided in the actual operation of electric power work. Experimental results show that difficulty of electric power work is reduced and the efficiency of actual work is improved. 展开更多
关键词 ELECTRIC POWER simulation TRAINING ELECTRIC POWER work ASSISTANCE AUGMENTED reality Image recognition
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谈建筑给排水施工图设计阶段与相关专业配合 预览
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作者 李国红 《山西建筑》 2019年第9期126-127,共2页
针对施工图设计阶段,围绕在建筑工程设计中建筑给排水专业需要密切配合的相关专业,根据相关规范要求,从各交叉专业角度分析需要配合及沟通的相关问题,提出需要向各专业提供的资料及设计中出现的矛盾,针对这些问题提出提供资料先后顺序... 针对施工图设计阶段,围绕在建筑工程设计中建筑给排水专业需要密切配合的相关专业,根据相关规范要求,从各交叉专业角度分析需要配合及沟通的相关问题,提出需要向各专业提供的资料及设计中出现的矛盾,针对这些问题提出提供资料先后顺序及解决办法。 展开更多
关键词 给排水 建筑工程 暖通 电气
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A 10-year follow-up of electric acupuncture for lumbar disc herniation and sciatica
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作者 顾华 《世界针灸杂志:英文版》 CSCD 2019年第3期221-223,共3页
Background:Lumbar disc herniation and sciatica are major causes of disability in health care.A variety of non-operative treatments are available,include acupuncture,while there is little long-term evidence to indicate... Background:Lumbar disc herniation and sciatica are major causes of disability in health care.A variety of non-operative treatments are available,include acupuncture,while there is little long-term evidence to indicate efficacy of acupuncture.Objective:To observe the long-term clinical effects of lumbar disc herniation and sciatica treated by acupuncture.Methods:Based on acupuncture point selections of the traditional Chinese medicine meridian theory,we developed the treatment strategies for acupuncture in a consensus process with the author's clinical and teaching practice.All 112 outpatients previously visited orthopedic surgeons or neurosurgeons and underwent(magnetic resonance imaging)MRI studies prior to having electric acupuncture treatment.This study used Oswestry Disability Index(ODI)-self-comparison and showed that acupuncture treatments for lumber disc herniation and sciatica demonstrated significant improvement in long term clinical outcomes.A total of 112 lumbar disc herniation and sciatica cases were treated with electric acupuncture for pain relief and function improvement from July 1998 to December 2006.Results:All the 112 cases filled out the ODI forms prior to receiving treatment.Among the 112 patients,23 of them did not finish the 6-week treatments.89 cases were evaluated with ODI after 6-week acupuncture treatments.Of those 89 cases,67 cases were followed up with ODI 10 years later.Significant improvement from the pre-to post-acupuncture ODI scores was observed(P<0.05).The 10-year follow-up ODI showed significant improvement with long-term results(P<0.05).Conclusion:Electric acupuncture for lumbar disc herniation and sciatica showed satisfactory long-term clinical effects. 展开更多
关键词 Electric acupuncture LUMBAR disc HERNIATION SCIATICA Low back PAIN LEG PAIN
特斯拉首个海外工厂落地上海 预览
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作者 Jimmy 《新世纪智能》 2019年第8期12-13,共2页
美国电动汽车公司特斯拉斥资9.73亿元,在上海港口附近租用一块86万平方米的土地,作为其在美国之外的第一家大型汽车厂的厂址。该公司正努力扩大在中国这个全球最大汽车市场的销量。特斯拉表示,该厂将于2021年投产,最初年产能约为25万辆... 美国电动汽车公司特斯拉斥资9.73亿元,在上海港口附近租用一块86万平方米的土地,作为其在美国之外的第一家大型汽车厂的厂址。该公司正努力扩大在中国这个全球最大汽车市场的销量。特斯拉表示,该厂将于2021年投产,最初年产能约为25万辆。上海市一个政府网站公布了这项租赁的费用。这种租赁通常的租期为50年。特斯拉在中国的销量受到了中美贸易摩擦不断升级的影响。该公司本月表示,由于关税和运输成本,其运营成本与中国生产商相比有55%至60%的劣势。该公司创始人埃隆·马斯克在8月份与投资者举行的电话会议上表示,上海工厂的资金将主要来自中资银行,而特斯拉'在2019年之前不会投入大量自有资金. 展开更多
关键词 特斯拉 电动汽车
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Vacuum-free fabrication of high-performance semitransparent perovskite solar cells via e-glue assisted lamination process
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作者 Hengkai Zhang Yaokang Zhang +6 位作者 Guang Yang Zhiwei Ren Wei Yu Dong Shen Chun-Shing Lee Zijian Zheng Gang Li 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第7期875-882,共8页
From a base material of conductive polymer(poly-(3,4-ethylenedioxythiophene):poly(styrenesulfonate),PEDOT:PSS),a flexible and high-conductivity(as low as 45Ω/sq)transparent electrode was fabricated on polydimethylsil... From a base material of conductive polymer(poly-(3,4-ethylenedioxythiophene):poly(styrenesulfonate),PEDOT:PSS),a flexible and high-conductivity(as low as 45Ω/sq)transparent electrode was fabricated on polydimethylsiloxane elastomer by an acid treatment and transfer process.Combined with the D-sorbitol-doped PEDOT:PSS electric glue,we successfully demonstrated a vacuum-free and ambient lamination fabrication process for semi-transparent perovskite solar cells using triple cation Cs0.05(MA0.17FA0.83)0.95Pb(I0.83Br0.17)3perovskite.By this manufacturing-friendly lamination process,we fabricated semitransparent perovskite solar cell devices with power conversion efficiencies up to 16.4%and variable transparencies. 展开更多
关键词 PEROVSKITE solar cells LAMINATION electric GLUE semi-transparent vacuum-free fabrication
Optimal design and development of PV-wind-battery based nano-grid system: a field-on-laboratory demonstration
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作者 B.TUDU K.K.MANDAL N.CHAKRABORTY 《能源前沿:英文版》 CSCD 2019年第2期269-283,共15页
The present paper has disseminated the design approach, project implementation, and economics of a nano-grid system. The deployment of the system is envisioned to acculturate the renewable technology into Indian socie... The present paper has disseminated the design approach, project implementation, and economics of a nano-grid system. The deployment of the system is envisioned to acculturate the renewable technology into Indian society by field-on-laboratory demonstration (FOLD) and ''bridge the gaps between research, develop-ment, and implementation.The system consists of a solar photovoltaic (PV)(2.4 kWp), a wind turbine (3.2 kWp), and a battery bank (400 Ah). Initially, a prefeasibility study is conducted using the well-established HOMER (hybrid optimization model for electric renewable) software developed by the National Renewable Energy Laboratory (NREL), USA. The feasibility study indicates that the optimal capacity for the nano-grid system consists of a 2.16 kWp solar PV, a 3 kWp wind turbine, a 1.44 kW inverter, and a 24 kWh battery bank. The total net present cost (TNPC) and cost of energy (COE) of the system are US$20789.85 and US$0.673/kWh,respectively. However, the hybrid system consisting of a 2.4 kWp of solar PV,a 3.2 kWp of wind turbine, a 3 kVA of inverter, and a 400 Ah of battery bank has been installed due to unavailability of system components of desired values and to enhance the reliability of the system.The TNPC and COE of the system installed are found to be US$20073.63 and US$0,635/kWh, respectively and both costs are largely influenced by battery cost. Besides, this paper has illustrated the installation details of each component as well as of the system. Moreover, it has discussed the detailed cost breakup of the system. Furthermore, the performance of the system has been investigated and validated with the simulation results. It is observed that the power generated from the PV system is quite significant and is almost uniform over the year. Contrary to this, a trivial wind velocity prevails over the year apart from the month of April,May,and June,so does the power yield. This research demonstration provides a pathway for future planning of scaled-up hybrid energy systems or microgrid in this region of I 展开更多
关键词 photovoltaic (PV) WIND battery nano-grid hybrid optimization model for electric renewable (HOMER) field-on-lab DEMONSTRATION (FOLD)
Powertrain control of a solar photovoltaic-battery powered hybrid electric vehicle
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作者 P.PADMAGIRISAN V.SANKARANARAYANAN 《能源前沿:英文版》 CSCD 2019年第2期296-306,共11页
This paper proposes a powertrain controller for a solar photovoltaic battery powered hybrid electric vehicle (HEV). The main objective of the proposed controller is to ensure better battery management, load regulation... This paper proposes a powertrain controller for a solar photovoltaic battery powered hybrid electric vehicle (HEV). The main objective of the proposed controller is to ensure better battery management, load regulation, and maximum power extraction whenever possible from the photovoltaic panels. The powertrain controller consists of two levels of controllers named lower level controllers and a high-level control algorithm. The lower level controllers are designed to perform individual tasks such as maximum power point tracking, battery charging, and load regulation. The perturb and observe based maximum power point tracking algorithm is used for extracting maximum power from solar photovoltaic panels while the battery charging controller is designed using a PI controller. A high-level control algorithm is then designed to switch between the lower level controllers based on different operating conditions such as high state of charge, low state of charge, maximum battery current, and heavy load by respecting the constraints formulated. The developed algorithm is evaluated using theoretical simula-tion and experimental studies. The simulation and experimental results are presented to validate the proposed technique. 展开更多
关键词 BATTERY management system hybrid electric vehicles (HEVs) MAXIMUM power point TRACKING (MPPT) solar PHOTOVOLTAIC
Study on Characteristics of Underground Horizontal Electric Field Caused by Lightning Return Stroke Based on FDTD Method 预览
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作者 Zhao Liang Gu Lili +1 位作者 Hao Ling Liu Ruixiang 《气象与环境研究:英文版》 CAS 2019年第1期39-42,共4页
Based on the MTLL lightning return stroke model, a two-dimensional cylindrical finite-difference time-domain (FDTD) model for underground horizontal electric field was established, and the effects of distance from lig... Based on the MTLL lightning return stroke model, a two-dimensional cylindrical finite-difference time-domain (FDTD) model for underground horizontal electric field was established, and the effects of distance from lightning channel, depth, soil electrical conductivity and its distribution, and return stroke current on the characteristics of underground horizontal electric field were analyzed. The results showed that as long as the electrical conductivity of soil existed, the peak of underground horizontal electric field decreased with the increase in the horizontal distance from lightning channel. When the electrical conductivity of the upper soil was much smaller than that of the lower soil, the peak of corresponding horizontal electric field was larger than the electric field peak as the electrical conductivity of the upper soil was larger than that of the lower soil. When the electrical conductivity of the upper soil was less than that of the lower soil, the growth and decay of the horizontal electric field were faster than the growth and decay as the electrical conductivity of the upper soil was larger than that of the lower soil. 展开更多
关键词 UNDERGROUND HORIZONTAL electric field LIGHTNING RETURN stroke FDTD Single layer soil LAYERED
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Smart product design for automotive systems
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作者 A.Galip ULSOY 《机械工程前沿:英文版》 CSCD 2019年第1期102-112,共11页
Automobiles evolved from primarily mechanical to electro-mechanical,or mechatronic,vehicles.For example,carburetors have been replaced by fuel injection and air-fuel ratio control,leading to order of magnitude improve... Automobiles evolved from primarily mechanical to electro-mechanical,or mechatronic,vehicles.For example,carburetors have been replaced by fuel injection and air-fuel ratio control,leading to order of magnitude improvements in fuel economy and emissions.Mechatronic systems are pervasive in modem automobiles and represent a synergistic integration of mechanics,electronics and computer science.They are smart systems,whose design is more challenging than the separate design of their mechanical,electronic and computer/control components.In this review paper,two recent methods for the design of mechatronic components are summarized and their applications to problems in automotive control are highlighted.First,the combined design,or co-design,of a smart artifact and its controller is considered.It is shown that the combined design of an artifact and its controller can lead to improved performance compared to sequential design.The coupling between the artifact and controller design problems is quantified,and methods for co-design are presented.The control proxy function method,which provides ease of design as in the sequential approach and approximates the performance of the co-design approach,is highlighted with application to the design of a passive/active automotive suspension.Second,the design for component swapping modularity(CSM)of a distributed controller for a smart product is discussed.CSM is realized by employing distributed controllers residing in networked smart components,with bidirectional communication over the network.Approaches to CSM design are presented,as well as applications of the method to a variable-cam-timing engine,and to enable battery swapping in a plug-in hybrid electric vehicle. 展开更多
关键词 MECHATRONICS automotive control CO-DESIGN component SWAPPING MODULARITY active SUSPENSIONS variable CAMSHAFT timing engine plug-in hybrid electric vehicle
Design scheme for fast charging station for electric vehicles with distributed photovoltaic power generation
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作者 Jing Zhang Chang Liu +5 位作者 Ruiming Yuan Taoyong Li Kang Li Bin Li Jianxiang Li Zhenyu Jiang 《全球能源互联网:英文版》 2019年第2期150-159,共10页
The demand for fast charging is increasing owing to the rapid expansion of the market for electric vehicles. In addition, the power generation technology for distributed photovoltaic has matured. This paper presents a... The demand for fast charging is increasing owing to the rapid expansion of the market for electric vehicles. In addition, the power generation technology for distributed photovoltaic has matured. This paper presents a design scheme for a fast charging station for electric vehicles equipped with distributed photovoltaic power generation system taking the area with certain conditions in Beijing as an example construction site. The technical indexes and equipment lectotype covering the general framework and subsystems of the charging station are determined by analyzing the charging service demand of fast charging stations. In this study, the layout of the station is developed and the operation benefits of the station is analyzed. The design scheme realizes the design objective of "rationalization, modularization and intelligentization" of the fast charging station and can be used as reference for the construction of a fast charging network in urban area. 展开更多
关键词 Electric VEHICLE Fast CHARGING STATION CHARGING DEMAND Design scheme DISTRIBUTED PHOTOVOLTAIC
A comprehensive review on hybrid electric vehicles: architectures and components 预览
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作者 Krishna Veer Singh Hari Om Bansal Dheerendra Singh 《现代交通学报:英文版》 2019年第2期77-107,共31页
The rapid consumption of fossil fuel and increased environmental damage caused by it have given a strong impetus to the growth and development of fuelefficient vehicles. Hybrid electric vehicles (HEVs) have evolved fr... The rapid consumption of fossil fuel and increased environmental damage caused by it have given a strong impetus to the growth and development of fuelefficient vehicles. Hybrid electric vehicles (HEVs) have evolved from their inchoate state and are proving to be a promising solution to the serious existential problem posed to the planet earth. Not only do HEVs provide better fuel economy and lower emissions satisfying environmental legislations, but also they dampen the effect of rising fuel prices on consumers. HEVs combine the drive powers of an internal combustion engine and an electrical machine. The main components of HEVs are energy storage system, motor, bidirectional converter and maximum power point trackers (MPPT, in case of solar-powered HEVs). The performance of HEVs greatly depends on these components and its architecture. This paper presents an extensive review on essential components used in HEVs such as their architectures with advantages and disadvantages, choice of bidirectional converter to obtain high efficiency, combining ultracapacitor with battery to extend the battery life, traction motors’ role and their suitability for a particular application. Inclusion of photovoltaic cell in HEVs is a fairly new concept and has been discussed in detail. Various MPPT techniques used for solar-driven HEVs are also discussed in this paper with their suitability. 展开更多
关键词 HYBRID electric vehicle HYBRID energy storage system Architecture TRACTION motors BIDIRECTIONAL CONVERTER
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Electrical activities of neural systems exposed to sinusoidal induced electric field with random phase
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作者 DU Lin CAO ZiLu +1 位作者 LEI YouMing DENG ZiChen 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第7期1141-1150,共10页
The brain neural system is often disturbed by electromagnetic and noise environments, and research on dynamic response of its interaction has received extensive attention. This paper investigates electrical activity o... The brain neural system is often disturbed by electromagnetic and noise environments, and research on dynamic response of its interaction has received extensive attention. This paper investigates electrical activity of Morris-Lecar neural systems exposed to sinusoidal induced electric field(IEF) with random phase generated by electromagnetic effect. By introducing a membrane depolarization model under the effect of random IEF, transition state of firing patterns, including mixed-mode oscillations(MMOs) with layered inter-spike intervals(ISI) and intermittency with a power law distribution in probability density function of ISI, is obtained in a single neuron. Considering the synergistic effects of frequency and noise, coherence resonance is performed by phase noise of IEF under certain parameter conditions. For the neural network without any internal coupling, we demonstrate that synchronous oscillations can be induced by IEF coupling, and suppression of synchronous spiking is achieved effectively by phase noise of IEF. Results of the study enrich the dynamical response to electromagnetic induction and provide insights into mechanisms of noise affecting information coding and transmission in neural systems. 展开更多
关键词 induced electric field random phase ELECTRICAL activity transition COHERENCE RESONANCE SYNCHRONOUS SUPPRESSION
Physical energies to the rescue of damaged tissues 预览
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作者 Federica Facchin Silvia Canaider +7 位作者 Riccardo Tassinari Chiara Zannini Eva Bianconi Valentina Taglioli Elena Olivi Claudia Cavallini Marco Tausel Carlo Ventura 《世界干细胞杂志:英文版(电子版)》 2019年第6期297-321,共25页
Rhythmic oscillatory patterns sustain cellular dynamics, driving the concerted action of regulatory molecules, microtubules, and molecular motors. We describe cellular microtubules as oscillators capable of synchroniz... Rhythmic oscillatory patterns sustain cellular dynamics, driving the concerted action of regulatory molecules, microtubules, and molecular motors. We describe cellular microtubules as oscillators capable of synchronization and swarming, generating mechanical and electric patterns that impact biomolecular recognition. We consider the biological relevance of seeing the inside of cells populated by a network of molecules that behave as bioelectronic circuits and chromophores. We discuss the novel perspectives disclosed by mechanobiology, bioelectromagnetism, and photobiomodulation, both in term of fundamental basic science and in light of the biomedical implication of using physical energies to govern (stem) cell fate. We focus on the feasibility of exploiting atomic force microscopy and hyperspectral imaging to detect signatures of nanomotions and electromagnetic radiation (light), respectively, generated by the stem cells across the specification of their multilineage repertoire. The chance is reported of using these signatures and the diffusive features of physical waves to direct specifically the differentiation program of stem cells in situ, where they already are resident in all the tissues of the human body. We discuss how this strategy may pave the way to a regenerative and precision medicine without the needs for (stem) cell or tissue transplantation. We describe a novel paradigm based upon boosting our inherent ability for self-healing. 展开更多
关键词 Stem cells PHYSICAL ENERGIES Mechanical forces Electric FIELDS ELECTROMAGNETIC FIELDS ELECTROMAGNETIC radiation PHOTOBIOMODULATION Damaged TISSUES
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一种小型多旋翼无人机的挂载设计与实现 预览
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作者 葛超 张植勋 +1 位作者 曾舒婷 夏庆锋 《兵工自动化》 2019年第3期88-91,共4页
为满足多旋翼无人机短距离挂载重物运输的需求,提出一种电动无人机自动化挂载重物方案。根据无人机飞行原理,对无人机现有挂载方案存在的问题进行分析,从易用性、可靠性、维护性、续航性、承载性对无人机性能进行评估,采用STM32芯片的... 为满足多旋翼无人机短距离挂载重物运输的需求,提出一种电动无人机自动化挂载重物方案。根据无人机飞行原理,对无人机现有挂载方案存在的问题进行分析,从易用性、可靠性、维护性、续航性、承载性对无人机性能进行评估,采用STM32芯片的抓持器,结合建模计算,通过对多旋翼飞行器及挂载控制系统的设计,得出其挂载方案,并通过抓持实验进行验证。试验结果表明:该方案切实可行,能基本满足大多数载荷的运输。 展开更多
关键词 无人机 STM32微型处理器 电动 STM32F103RCT6
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HTR and GRIN2B Variant Associated with Cognition Dysfunction in Electric Workers 预览
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作者 WANG Li Feng LI Hai Juan +10 位作者 REN Cai Xia ZOU Yong QIAO Si Mo ZHI Wei Jia WANG Chang Zhen ZHAO Li DONG Ji XU Xin Ping HU Shao Hua PENG Rui Yun HU Xiang Jun 《生物医学与环境科学:英文版》 SCIE CAS CSCD 2019年第3期220-225,共6页
The frequency of an extremely low frequency electromagnetic field (ELF-EMF) ranges from 3 to 3, 000 Hz. Workers who are exposed to ELF-EMF include electric power installers and repairers, power plant operators, electr... The frequency of an extremely low frequency electromagnetic field (ELF-EMF) ranges from 3 to 3, 000 Hz. Workers who are exposed to ELF-EMF include electric power installers and repairers, power plant operators, electricians, electrical fitters, other such professionals. The main work categories in an electrical company or for utility work can be defined according to the five main stages of electricity production and distribution. Studies on the central nervous system (CNS) reported depressed activity in the different neurotransmitter systems and decreased protein content in the brains of animals exposed to ELF-EMF. Some studies reported differences with respect to change in brain function after electromagnetic radiation among individuals[1]. 展开更多
关键词 HTR and GRIN2B COGNITION DYSFUNCTION ELECTRIC Workers
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An innovative method for the microstructural modification of TiAl alloy solidified via direct electric current application
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作者 Zhanxing Chen Hongsheng Ding +3 位作者 Ruirun Chen Shiqiu Liu Jingjie Guo Hengzhi Fu 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第1期23-28,共6页
Ti-48Al-2Cr-2Nb alloy solidified with the application of direct electric current has a refined and homogeneous microstructure without segregation. We observed an initial decrease followed by a subsequent increase in g... Ti-48Al-2Cr-2Nb alloy solidified with the application of direct electric current has a refined and homogeneous microstructure without segregation. We observed an initial decrease followed by a subsequent increase in grain size and lamellar spacing, with the increase in current density. Similar trend can also be obtained by varying the amount of α2-phase(Ti3Al). Using a directional solidification processing method,the columnar crystal microstructure transforms into an equiaxed crystal microstructure at a current density of 32–64 m A/mm2. High dislocation density is also introduced with a minimum cross-sectional grain size of 460 μm at a current density of 64 mA/mm2. The application of electric current alters the free energy of the critical nucleus and temperature via joule heating, causing a transformation from a columnar grain microstructure into an equiaxed grain microstructure. The increase in current density leads to a rise of the nucleation rate, and a resulting undercooling combined with temperature gradient contribute to growth of the primary phase, which finally results in grain coarsening at a critical current density of 96 mA/mm2.The climb and cross-slip of dislocation and the migration of grain boundary ultimately create variable lamellae spacing of TiAl alloy. 展开更多
关键词 TIAL SOLIDIFICATION DIRECT electric current Microstructure
新型电动果子采摘机设计 预览
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作者 张文斌 郭德伟 +2 位作者 江洁 俞利宾 闵洁 《中国农机化学报》 北大核心 2019年第6期52-55,共4页
针对目前黑腰枣采摘过程中,由于黑腰枣的结果枝条和枣吊上长有细刺,人工在进行采摘时,不仅费时费力,而且容易被刺扎伤的现状,设计一种新型的电动果子采摘机。该机采用马达带动刷辊旋转,依靠刷辊上的梳齿将枣子刷下,梳齿采用橡胶材料制成... 针对目前黑腰枣采摘过程中,由于黑腰枣的结果枝条和枣吊上长有细刺,人工在进行采摘时,不仅费时费力,而且容易被刺扎伤的现状,设计一种新型的电动果子采摘机。该机采用马达带动刷辊旋转,依靠刷辊上的梳齿将枣子刷下,梳齿采用橡胶材料制成,在采摘过程中不会损伤枣子,而果兜的设计使得采摘下来的枣子便于收集,电瓶驱动马达的方式提高了采摘机使用的灵活性。在理论设计的基础上,完成实物样机的制作,并对黑腰枣进行实际采摘试验,实际测试结果表明,该机解决目前黑腰枣采摘过程中费时费力且易扎伤人的问题,对于提高采摘效率和降低采摘时对黑腰枣的损伤发挥极大作用。 展开更多
关键词 果子采摘机 电动 设计 新型 梳齿 果兜
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Interdependence between transportation system and power distribution system: a comprehensive review on models and applications 预览
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作者 Wei WEI Danman WU +2 位作者 Qiuwei WU Miadreza SHAFIE-KHAH Joao PSCATALAO 《现代电力系统与清洁能源学报(英文)》 CSCD 2019年第3期433-448,共16页
The rapidly increasing penetration of electric vehicles(EVs) in modern metropolises has been witnessed during the past decade, inspired by financial subsidies as well as public awareness of climate change and environm... The rapidly increasing penetration of electric vehicles(EVs) in modern metropolises has been witnessed during the past decade, inspired by financial subsidies as well as public awareness of climate change and environment pro-tection. Integrating charging facilities, especially highpower chargers in fast charging stations, into power distribution systems remarkably alters the traditional load flow pattern, and thus imposes great challenges on the operation of distribution network in which controllable resources are rare. On the other hand, provided with appropriate incentives, the energy storage capability of electric vehicle offers a unique opportunity to facilitate the integration of distributed wind and solar power generation into power distribution system. The above trends call for thorough investigation and research on the interdependence between transportation system and power distribution system. This paper conducts a comprehensive survey on this line of research. The basic models of transportation system and power distribution system are introduced,especially the user equilibrium model, which describes the vehicular flow on each road segment and is not familiar to the readers in power system community. The modelling of interdependence across the two systems is highlighted.Taking into account such interdependence, applications ranging from long-term planning to short-term operation are reviewed with emphasis on comparing the description of traffic-power interdependence. Finally, an outlook of prospective directions and key technologies in future research is summarized. 展开更多
关键词 CHARGING STATION Electric vehicle(EV) INTERDEPENDENCE POWER flow POWER distribution SYSTEM Transportation SYSTEM User EQUILIBRIUM
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