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基于地理信息系统技术的大规模地块负荷统计方法 认领
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作者 冯华然 庾力维 +2 位作者 何敬开 梁锡亮 蔡昭群 《广东电力》 2021年第1期58-65,共8页
准确统计地块现状负荷对配电网规划和负荷管理意义重大,供电部门现有各数据系统无统计地块负荷功能,传统统计方法依赖于人工,不适合大规模统计,为此提出一种基于地理信息系统(geographic information system,GIS)技术的统计方法。该方... 准确统计地块现状负荷对配电网规划和负荷管理意义重大,供电部门现有各数据系统无统计地块负荷功能,传统统计方法依赖于人工,不适合大规模统计,为此提出一种基于地理信息系统(geographic information system,GIS)技术的统计方法。该方法首先根据城市总体规划和控制性详细规划建立地块GIS信息数据库;然后利用二次开发MapInfo功能,确定配用变压器与地块的耦合关系,模拟各配用变压器日负荷曲线,叠加统计各地块现状负荷。最后以某市配电网为例对全市地块现状负荷进行计算,结果表明该方法能够实现大规模地块现状负荷统计,提高统计效率和统计结果可靠性。 展开更多
关键词 地理信息系统 地块 空间负荷 配用变压器 配电网规划 网格
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1LFT-555型液压翻转栅条犁的设计与试验 认领
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作者 雷智高 郑炫 +2 位作者 汤智辉 杨怀君 孟祥金 《农机化研究》 北大核心 2021年第2期174-179,共6页
针对当前农业生产需求及147kW以上拖拉机配套液压翻转犁依赖进口的现状,研制了1LFT-555型液压翻转栅条犁。该机翻转可靠性高,操作简单,主犁体采用栅条式结构,翻垡覆盖效果好,耕作阻力小。田间试验结果表明:该机和不同功率及多种轮距的... 针对当前农业生产需求及147kW以上拖拉机配套液压翻转犁依赖进口的现状,研制了1LFT-555型液压翻转栅条犁。该机翻转可靠性高,操作简单,主犁体采用栅条式结构,翻垡覆盖效果好,耕作阻力小。田间试验结果表明:该机和不同功率及多种轮距的拖拉机配套使用,作业速度可达10.8km/h,犁耕作业效果好,在棉花地和水稻地的耕深稳定性系数及耕宽稳定性系数均达到了95%以上,在棉花地的碎土率也达到了90%以上。该机各项性能指标达到国家有关标准的要求,为147kW以上拖拉机提供了配套犁耕机具。 展开更多
关键词 犁体 翻转犁 液压 栅条
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Recent progress on the study of distributed economic dispatch in smart grid:an overview 认领
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作者 Guanghui WEN Xinghuo YU Zhiwei LIU 《信息与电子工程前沿:英文版》 SCIE EI 2021年第1期25-39,共15页
Designing an efficient distributed economic dispatch(DED)strategy for the smart grid(SG)in the presence of multiple generators plays a paramount role in obtaining various benefits of a new generation power syst em,suc... Designing an efficient distributed economic dispatch(DED)strategy for the smart grid(SG)in the presence of multiple generators plays a paramount role in obtaining various benefits of a new generation power syst em,such as easy implementation,low maintenance cos t,high energy efficiency,and strong robus tn ess agains t uncertainties.It has drawn a lot of interest from a wide variety of scientific disciplines,including power engineering,control theory,and applied mathematics.We present a state-of-the-art review of some theoretical advances toward DED in the SG,with a focus on the literature published since 2015.We systematically review the recent results on this topic and subsequently categorize them into distributed discrete-and continuous-time economic dispatches of the SG in the presence of multiple generators.After reviewing the literature,we briefly present some future research directions in DED for the SG,including the distributed security economic dispatch of the SG,distributed fast economic dispatch in the SG with practical constraints,efficient initialization-free DED in the SG,DED in the SG in the presence of smart energy storage batteries and flexible loads,and DED in the SG with artificial intelligence technologies. 展开更多
关键词 Distributed economic dispatch Distributed optimization Smart grid Continuous-time optimization algorithm Discrete-time optimization algorithm
基于小波分析的电网输电设备故障智能监测系统设计 认领
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作者 王业凡 吴星昂 +2 位作者 高建东 沈捷 吴晶莹 《电子设计工程》 2021年第2期137-141,共5页
传统的电网输电设备故障智能监测系统中存在健全能能量高于故障能能量的情况,造成监测数据不完全,为解决该问题,设计基于小波分析电网输电设备故障智能监测系统。在硬件设计上,选择AT89C51型号的单片机作为核心处理器,设计引脚功能,保... 传统的电网输电设备故障智能监测系统中存在健全能能量高于故障能能量的情况,造成监测数据不完全,为解决该问题,设计基于小波分析电网输电设备故障智能监测系统。在硬件设计上,选择AT89C51型号的单片机作为核心处理器,设计引脚功能,保证数据传输,在原有的信号调整模块中,选择LM324作为运算放大器,控制故障信号的放大;在软件设计上,根据采集的电流和电压数据计算对应的有效值,将其作为输入、输出故障信号,选取Haar小波函数,提取故障信号特征向量,实现故障监测。结合硬件和软件设计完成整个系统设计。测试结果表明:与传统的故障监测系统相比,设计的基于小波分析电网输电设备故障智能监测系统中故障能能量高于健全能能量。 展开更多
关键词 小波分析 电网 输电设备 故障监测
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文章速递基于地面激光扫描仪的隧道断面提取研究 认领
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作者 方俊杰 《测绘与空间地理信息》 2021年第2期212-214,217,共4页
近年来,将三维激光扫描技术应用于地铁变形监测成为研究的热点。面对海量点云数据,如何提取隧道断面是成功运用该技术的关键。据此,本文采用三维激光扫描技术扫描隧道,获取隧道整体点云数据,并提出一种获取隧道任意位置断面变形的新方... 近年来,将三维激光扫描技术应用于地铁变形监测成为研究的热点。面对海量点云数据,如何提取隧道断面是成功运用该技术的关键。据此,本文采用三维激光扫描技术扫描隧道,获取隧道整体点云数据,并提出一种获取隧道任意位置断面变形的新方法。以某地铁监测数据为例实验分析,提取隧道断面图,实验证明了该方法的有效性。 展开更多
关键词 地面激光扫描仪 隧道 地铁 断面 格网化
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Smart Grid: Future of Electrical Transmission and Distribution 认领
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作者 Kamal Kant Sharma Himanshu Monga 《通讯、网络与系统学国际期刊(英文)》 2020年第4期45-54,共10页
For century, the need of change in the system of power grid is being felt and being considered as the most important change that we need in the modern era electrical system but before moving towards a new change the t... For century, the need of change in the system of power grid is being felt and being considered as the most important change that we need in the modern era electrical system but before moving towards a new change the things in past should be kept in mind so that there are better chances of great and beneficial change. The purpose of this research is to investigate the changes need to be incorporated in a conventional system to make a system self-sufficient and automated in order to make Electrical Power system more reliable. This paper assesses the current one way power system that is needed to be changed and has tried to provide an overview of the changes that we need in the system. The paper has focused more on the smart grid system and has explained the importance of smart grid system in terms of efficiency, automation and decision making capability in case of faults occurred on primitive grids with the help of comparative studies. The paper also highlighted the results in form of comparison with conventional grids and threw some light on the vision, control and the application of the smart grid system that will provide a two way system to the electrical network of the country and will make the distribution and consumption of energy more efficient also which is going to increase the reliability and accuracy in the system. 展开更多
关键词 Smart Grid Automatic Grid System Vision of Smart Grid Communication Technologies
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Secure and Performant Handling CIM-Based Data Streams in Control Room Software Interaction for Multi Vendor Solutions 认领
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作者 Benjamin Requardt Sebastian Wende-von Berg Martin Braun 《智能信息管理(英文)》 2020年第1期43-62,共20页
Due to the increasing share of renewable energy, new requirements are placed on control room software. Such software is often exclusive to the supplier, but other suppliers could offer new and better methods. For secu... Due to the increasing share of renewable energy, new requirements are placed on control room software. Such software is often exclusive to the supplier, but other suppliers could offer new and better methods. For security reasons, external applications often have no direct data access to control room software. Such software can provide information about the power grid via a periodic file transfer in CIM (Common Information Model) format. These files are often very large, containing complete records, delivering information not always relevant to the external applications. Extracting the relevant information required by external applications can be time-consuming, thus presenting a problem for time-critical applications. This paper presents a method allowing different applications to efficiently access the relevant data from the massive data stream contained in the CIM files. This method has been tested with a distribution system operator and clearly increases performance, allowing different applications to access the relevant data. 展开更多
关键词 Common Information Model (CIM) GRID Control Room SOFTWARE Electrical GRID
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Multi-stage power source and grid coordination planning method considering grid uniformity 认领
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作者 Zhiqi Li Xueshan Han +1 位作者 Ming Yang Yiran Ma 《全球能源互联网:英文版》 2020年第4期303-312,I0001,共11页
Given the increasing uncertainties in power supply and load,this paper proposes the concept of power source and grid coordination uniformity planning.In this approach,the standard deviation of the transmission line lo... Given the increasing uncertainties in power supply and load,this paper proposes the concept of power source and grid coordination uniformity planning.In this approach,the standard deviation of the transmission line load rate is considered as the uniformity evaluation index for power source and grid planning.A multi-stage and multi-objective optimization model of the power source and grid expansion planning is established to minimize the comprehensive cost of the entire planning cycle.In this study,the improved particle swarm optimization algorithm and genetic algorithm are combined to solve the model,thus improving the efficiency and accuracy of the solution.The analysis of a simple IEEE Garver’s 6-node system shows that the model and solution method are effective and feasible.Moreover,they are suitable for the coordinated planning of the power source and grid under a diversified nature of power supply and load. 展开更多
关键词 Power source and grid coordination Grid uniformity Grid expansion planning Evaluation index of uniformity
局部网格动态聚类算法 认领
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作者 王玮琪 万仁霞 周方祥 《现代电子技术》 北大核心 2020年第1期102-106,共5页
针对传统网格聚类算法聚类精度较低,处理流数据效率较低等问题进行改进。提出局部网格动态聚类算法,算法引入维度半径概念进行增量动态网格划分,通过采用新的簇边界判定方法对簇边界进行判定,依据稀疏网格与其邻接密集网格的质心距离,... 针对传统网格聚类算法聚类精度较低,处理流数据效率较低等问题进行改进。提出局部网格动态聚类算法,算法引入维度半径概念进行增量动态网格划分,通过采用新的簇边界判定方法对簇边界进行判定,依据稀疏网格与其邻接密集网格的质心距离,将稀疏网格归并到相应网格簇中,对于不能归并的稀疏网格则采用局部网格划分方法对稀疏网格再次进行划分聚类,避免簇边界的误删,在一定程度上提高了聚类精确度。通过对比实验结果表明提出的算法具有更好的聚类时效性和聚类精度。 展开更多
关键词 网格 局部密度 聚类算法 密集网格 稀疏网格 簇边界
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基于电网电压全前馈的电网背景谐波抑制研究 认领
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作者 柴秀慧 张纯江 +1 位作者 赵晓君 孙菲 《电力电子技术》 CSCD 北大核心 2020年第8期5-7,18,共4页
弱电网的特征之一是严重的背景谐波,导致并网电流出现明显的畸变。以LCL型并网逆变器为研究对象,提出一种电网电压全前馈控制,可以有效抑制电网电压背景谐波对并网电流的影响从而提高并网电能质量。首先,分析电网电压对并网电流的影响机... 弱电网的特征之一是严重的背景谐波,导致并网电流出现明显的畸变。以LCL型并网逆变器为研究对象,提出一种电网电压全前馈控制,可以有效抑制电网电压背景谐波对并网电流的影响从而提高并网电能质量。首先,分析电网电压对并网电流的影响机理,从而在电流控制环路中引入一个正的电网电压反馈来抵消电网电压对并网电流的影响。通过控制框图等效变换,推导出消除背景谐波影响所需的电网电压全前馈函数。其次,通过全前馈函数的深入分析,得出根据电网电压含有谐波频次的不同,对全前馈函数进行优化设计的方法。在保证前馈控制效果的同时,简化控制算法。最后,通过实验验证了所提控制策略的有效性和可行性。 展开更多
关键词 电网 电网电压全前馈 电网背景谐波
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Safer Design and Less Cost Operation for Low-Traffic Long-Road Illumination Using Control System Based on Pattern Recognition Technique 认领
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作者 Muhammad M. A. S. Mahmoud Leyla Muradkhanli 《智能控制与自动化(英文)》 2020年第3期47-62,共16页
The paper covers analysis and investigation of lighting automation system in low-traffic long-roads. The main objective is to provide optimal solution between expensive safe design that utilizes continuous street ligh... The paper covers analysis and investigation of lighting automation system in low-traffic long-roads. The main objective is to provide optimal solution between expensive safe design that utilizes continuous street lighting system at night for the entire road, or inexpensive design that sacrifices the safety, relying on using vehicles lighting, to eliminate the problem of high cost energy consumption during the night operation of the road. By taking into account both of these factors, smart lighting automation system is proposed using Pattern Recognition Technique applied on vehicle number-plates. In this proposal, the road is sectionalized into zones, and based on smart Pattern Recognition Technique, the control system of the road lighting illuminates only the zone that the vehicles pass through. Economic analysis is provided in this paper to support the value of using this design of lighting control system. 展开更多
关键词 Road Lighting Control Road Lighting Automation Vehicle Number-Plate Pattern Recognition Smart Grid Power Management Low Traffic Roads Image Processing
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双电源转换开关电网信号检测电路设计 认领 被引量:1
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作者 黄雨龙 李靖 田新疆 《电器与能效管理技术》 2020年第3期43-49,共7页
风能的波动性、间接性和随机性等特性对接入风电的电网运行特性和电能质量(如电压、频率偏差)造成影响。双电源转换开关作为电网中连续供电的一种保障,广泛应用于各种重要负载场合。完成电网信号现场参量及其检测是双电源转换开关的首... 风能的波动性、间接性和随机性等特性对接入风电的电网运行特性和电能质量(如电压、频率偏差)造成影响。双电源转换开关作为电网中连续供电的一种保障,广泛应用于各种重要负载场合。完成电网信号现场参量及其检测是双电源转换开关的首要任务之一。针对风电机组并网运行中的电网电能质量问题,就双电源转换开关电网信号检测电路分别进行了硬件和软件设计。硬件设计以TMS320F28335数字信号处理器为核心控制模块,利用其内部的模/数转换器和捕获模块对电网中的电压和频率进行检测;软件设计则编写了电压和频率的采样和算法程序。该电网信号检测电路具有采样精度高、硬件成本低、检测算法简单等优点,可以最大化保障重要负载的连续供电。 展开更多
关键词 电网 电能质量 双电源转换开关 电网信号检测 数字信号处理器
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Smart Boilers: Grid Support Services from Non-Critical Loads 认领
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作者 Panagis N. Vovos Konstantinos G. Georgakas 《电力能源(英文)》 2020年第12期23-45,共23页
The aim of this paper is to present the concept of a simple and cheap upgrade for electric water boilers, allowing them to provide power quality services to the distribution grid. The upgrade requires only minimum add... The aim of this paper is to present the concept of a simple and cheap upgrade for electric water boilers, allowing them to provide power quality services to the distribution grid. The upgrade requires only minimum additional hardware and it is easily installable. “Smart Boilers”, as the upgraded boilers are named, perform precise active and reactive power control, but most significantly mitigate line current harmonics. Αctive and reactive power control is implemented by appropriate regulation of the modulation sinewave amplitude and phase, respectively. This type of control is easily customizable in order to accommodate a variety of power quality targets, depending on the required level of services and available grid monitoring equipment. The method used for line current harmonic compensation is based on the injection of mirror harmonics created at the modulation stage of the converter. It is indifferent of harmonic source: it is equally successful at mitigating harmonics caused by the power electronic converter of the Smart Boiler, other sources of current harmonics or loads. The achieved grid services are clearly beyond the “on/off” operation of electric boilers, currently implemented by Demand Side Management (DSM) in order to shift load away from peak hours. It has been demonstrated through simulations, that Smart Boilers can assist voltage regulation at terminal buses, compensate reactive power and suppress harmonic currents at lines. 展开更多
关键词 Electrical Grid Improvement High Harmonics Minimization Smart Boilers Smart Power Grids Active Power Control Reactive Power Compensation
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Techno-Economic Evaluation and Optimization of Grid Connected PV and Wind Generating System for Riyadh City 认领
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作者 Fahd A. Alturki Abdulhakim Bin Dayil 《电力能源(英文)》 2020年第12期46-63,共18页
The risks and challenges faced by human society at the moment are global warming, climate change and pollution. In addition to their effect on the atmosphere, the quantity of fossil fuels is beginning to decrease, and... The risks and challenges faced by human society at the moment are global warming, climate change and pollution. In addition to their effect on the atmosphere, the quantity of fossil fuels is beginning to decrease, and countries have taken steps to encourage greater use of renewable energy resources. This article explores the feasibility of supplying electricity from a hybrid power system (HPS) comprising wind/photovoltaic (PV) and batteries. Taking into account residential buildings that consume the largest portion of energy in Saudi grid<span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> Saudi Arabia, Riyadh is the preferred city with distinctive geographical and climatic conditions. The hourly electricity demand data must be over 8760 hours during a 1-year analysis in order to assess the optimum design and operational planning of the HPS. The economic analysis is carried out by applying HOMER software on the basis of net present cost (NPC), energy cost (COE) and the renewable fraction for all situations. In addition, to specify the effect of fuel costs on the scheme, sensitivity tests are carried out by considering two separate tariff rates for residential consumers. The results of the economic analysis show that current tariff is not economic to </span><span style="font-family:Verdana;">use HSP under warm and temperate climate conditions compare to using</span><span style="font-family:Verdana;"> electricity from grid and the expected forecasted tariff shows it’s economic to use HSP compare to grid electricity.</span></span></span></span> 展开更多
关键词 Solar GRID Optimization COST HOMER Pro® Software
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Forecasting-Based Adaptive Optimized Dispatch in Smart Grid Online 认领
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作者 Qiang Jiang Dan Hu Duyi He 《现代非线性理论与应用(英文)》 2020年第1期1-18,共18页
The power grid is a fusion of technologies in energy systems, and how to adjust and control the output power of each generator to balance the load of the grid is a crucial issue. As a platform, the smart grid is for t... The power grid is a fusion of technologies in energy systems, and how to adjust and control the output power of each generator to balance the load of the grid is a crucial issue. As a platform, the smart grid is for the convenience of the implementation of adaptive control generators using advanced technologies. In this paper, we are introducing a new approach, the Central Lower Configuration Table, which optimizes dispatch of the generating capacity in a smart grid power system. The dispatch strategy of each generator in the grid is presented in the configuration table, and the scenario consists of two-level agents. A central agent optimizes dispatch calculation to get the configuration table, and a lower agent controls generators according to the tasks of the central level and the work states during generation. The central level is major optimization and adjustment. We used machine learning to predict the power load and address the best optimize cost function to deal with a different control strategy. We designed the items of the cost function, such as operations, maintenances and the effects on the environment. Then, according to the total cost, we got a new second-rank-sort table. As a result, we can resolve generator’s task based on the table, which can also be updated on-line based on the environmental situation. The signs of the driving generator’s controller include active power and system’s f. The lower control level agent carries out the generator control to track f along with the best optimized cost function. Our approach makes optimized dispatch algorithm more convenient to realize, and the numerical simulation indicates the strategy of machine learning forecast of optimized power dispatch is effective. 展开更多
关键词 MACHINE Learning SMART GRID ADAPTIVE Control DISPATCH Power ONLINE
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Evaluation of Mobile Electronic Devices in Detecting Optic Disc and Visual Field Parameters in Patients with Glaucoma at a Tertiary Hospital in Northeastern Tanzania 认领
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作者 Francisco Alcides Mulobuana Tolbert Sonda +1 位作者 Martin M. Rwabilimbo William Makupa 《眼科学期刊(英文)》 2020年第3期230-238,共9页
<strong>Background:</strong> Glaucoma is a serious public health problem since it causes visual impairment impacting social, mental and physical health of an individual. Diagnosis and management of glaucom... <strong>Background:</strong> Glaucoma is a serious public health problem since it causes visual impairment impacting social, mental and physical health of an individual. Diagnosis and management of glaucoma continue to be a challenge due to few qualified personnel and high cost of the equipment. The use of portable Eye Examination Kit such as Smartphone and tablets can be used in glaucoma screening for taking high-resolution fundus photos for optic disc and visual field parameters, respectively. This study was conducted to evaluate the applicability of mobile electronic device to detect optic disc and visual field parameters for glaucoma in a resource limited setting. <strong>Objective:</strong> To evaluate the applicability of mobile electronic devices to detect optic disc and visual field parameters for glaucoma. <strong>Methodology:</strong> Across-sectional study was conducted at KCMC Eye department from October 2018 to June 2019. Study included 140 participants attending eye clinic of which 67 had glaucoma and 73 without glaucoma. Clinical and socio-demographic data were collected using a structured questionnaire and analysed using Stata 15. Glaucoma examination was made on the right eye and photo comparison made between those with and without glaucoma. PEEK Smartphone fundus photo examination was compared with the gold standard machine (Slit Lamp Biomicroscopy), Amsler grid chart installed on a tablet (Microsoft surface, internal storage 256 GB, 2013) and contrast sensitivity compared with Humphrey field analyser (i series, model 740117434, Carl Zeiss Meditec). <strong>Results:</strong> The kappa (k) agreement between Slit lump biomicroscopy fundus view image and PEEK Smartphone concerning the optic disc measurement was 0.92 with sensitivity and specificity of 90.32% (95% CI: 80.12 - 96.37) and 93.59% (95% CI: 85.67 - 97.89) with a p < 0.001 respectively. An agreement between Amsler grid and Humphrey Field Analyser was 0.67 with sensitivity of 33.33% (95% CI: 20.76 - 47.92) and specificity of 86.52% (95% CI 展开更多
关键词 GLAUCOMA PEEK Smartphone Contrast Sensitivity Amsler Grid KILIMANJARO
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新时代我国农村社区网格化服务管理创新研究——基于S省网格化政策实践调查 认领
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作者 伊庆山 《兰州学刊》 CSSCI 2020年第9期171-186,共16页
在社会治理创新视域下,网格化服务管理作为一项推进城乡基层社区善治的有益探索,迎合了国家推动社会治理重心向基层下移和治理方式从管理向管理与服务并重的方向性转变,被顶层设计者和地方政府看作是能够有效应对基层社会治理问题的政... 在社会治理创新视域下,网格化服务管理作为一项推进城乡基层社区善治的有益探索,迎合了国家推动社会治理重心向基层下移和治理方式从管理向管理与服务并重的方向性转变,被顶层设计者和地方政府看作是能够有效应对基层社会治理问题的政策工具。从政策实践调研看,农村社区网格化服务管理积极回应农村社区治理现实困境,糅合国家治理创新和城乡基层社会治理创新要素,完善了组织架构、运行机制和制度保障。但从实际运行绩效看,仍存在工作开展不均衡、网格队伍结构仍待优化、综合信息系统有待完善、服务管理能力有待提升等客观不足,进而制约了党建引领、社区自治、群众参与、政社协同等善治因素发挥预期作用。因此,为推进农村社区网格化服务管理工作健康发展和提高基层社会治理现代化水平,应有针对性的构建高质量农村社区网格化服务管理体系,提升农村社区网格化服务管理能力和促进网格化与社区善治要素相融合。 展开更多
关键词 网格 网格化 农村社区 网格化服务管理 社区治理
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Stability Enhancement of Small-Scale Power Grid with Renewable Power Sources by Variable Speed Diesel Power Plant 认领
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作者 Rion Takahashi Atsushi Umemura Junji Tamura 《电力能源(英文)》 2020年第3期1-17,共17页
This paper proposes a power control method to improve a stability of a small-scale power grid with renewable energy sources. In an isolated small- scale power grid such as an island, diesel power plant is main power s... This paper proposes a power control method to improve a stability of a small-scale power grid with renewable energy sources. In an isolated small- scale power grid such as an island, diesel power plant is main power source which has an environmental burden and expensive running cost due to high priced fossil fuel. Thus, expanding installation of the renewable energy sources such as a wind power is strongly desirable. Such fluctuating energy sources, however, harm power quality of the small-scale power grid, and in addition, conventional power plant in the small-scale power grid cannot, in general, stabilize the grid system with such fluctuating power sources. In this study, Variable Speed Doubly-Fed Induction Generator (VS-DFIG) is proposed to be in-stalled at a diesel power plant instead of a conventional Fixed Speed Synchronous Generator (FS-SG), because quick control of a power balance in the small-scale power grid can be achieved by using the inertial energy of VS-DFIG. In addition, utilization of a Battery Energy Storage System (BESS) is also considered to assist cooperatively the VS-DFIG control. As a result of the simulation analysis by using the proposed method, it is verified that frequency fluctuations due to renewable energy source can be effectively reduced by quick power control of the VS-DFIG compared to the conventional FS-SG, and further control ability can be obtained by utilizing BESS. Moreover, the transient stability of a small-scale power grid during a grid fault can also be enhanced. 展开更多
关键词 SMALL-SCALE POWER Grid Variable Speed DOUBLY-FED Induction Generator (VS-DFIG) DIESEL POWER Plant Wind POWER Battery Energy Storage System (BESS)
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Agents for Smart Power Grids 认领
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作者 Salem Al-Agtash Hossam Abdel Hafez 《能源与动力工程(英文)》 2020年第8期477-489,共13页
The future of electricity systems will compose of small-scale generation and distribution where end-users will be active participants with localized energy management systems that are able to interact on a free energy... The future of electricity systems will compose of small-scale generation and distribution where end-users will be active participants with localized energy management systems that are able to interact on a free energy market. Software agents will most likely control power assets and interact together to decide the best and safest configuration of the power grid system. This paper presents a design of agents that can be deployed in real-time with capabilities that include optimization of resources, intensive computation, and appropriate decision-making. Jordan 51-bus system has been used for simulation with a total generation capacity of 4050 MW of which 230 MW represent</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> renewable energy. The economic analyses demonstrated the use of smart grid technologies with 2016 generation</span><span style="font-family:""><span style="font-family:Verdana;">—</span><span style="font-family:Verdana;">load profiles for nominal liquified gas (NLG) prices and </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;">20% sensitivity analysis. The results have shown variations in the range of 1% in the price of MWh with smart grid technologies. These variations are mainly driven by the fact that agents shift power generation to renewable power plants to produce maximum power at peak hours. As a result, there is a positive economic impact in both NLG </span><span style="font-family:Verdana;">±</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">20% sensitivity analysis, due to the fact that agents coordinate to better displace expensive thermal generation with renewable generation. It is evident that renewable resources compensate for power at peak times and provide economic benefits and savings. 展开更多
关键词 AGENTS Electric Power System Smart Power Grid
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基于方形邻域的网格密度聚类算法 认领 被引量:1
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作者 兰红 朱合隆 《计算机应用研究》 CSCD 北大核心 2020年第6期1735-1740,共6页
针对大数据聚类低效的问题,提出一种方形邻域快速网格密度聚类算法(square-neighborhood and gridbased DBSCAN,SGBSCAN)。首先给出方形邻域密度聚类定义,利用方形邻域代替圆形邻域,降低时间复杂度;其次提出方形邻域密度聚类的grid概念... 针对大数据聚类低效的问题,提出一种方形邻域快速网格密度聚类算法(square-neighborhood and gridbased DBSCAN,SGBSCAN)。首先给出方形邻域密度聚类定义,利用方形邻域代替圆形邻域,降低时间复杂度;其次提出方形邻域密度聚类的grid概念,快速确定高密度区域内核心点与数据点之间的密度关系;最后提出grid密度簇,利用网格之间的关系加快密度簇的形成。算法应用于16个数据集,分别与已有文献算法进行对比,结果表明所提算法在聚类效率方面有显著提升,数据量越大算法效率提升越明显,且该算法适用于多维数据的聚类。 展开更多
关键词 聚类分析 密度聚类 方形邻域 网格 网格簇
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