Results 11 to 20 of about 1,385 (159)
Gaoya dianqi, 2021 架空地线因其不存在负载电流(除了很小的感应电流外),在冬季冰冻雨雪天气下较输电导线更易产生覆冰现象。而为了达到防雷效果,架空地线必须经铁塔可靠接地,这与在通电融冰工况下需使其对地绝缘相矛盾。文中针对所提出的一种220 kV防雷防冰灾架空地线系统,在简介其拓扑结构与工作原理基础上,根据该架空地线电缆参数及假设的融冰场景,通过计算直流融冰电流、电压,确定直流融冰电源的额定输出容量,并对该直流融冰电源的全桥模块化多电平换流器等核心部件的结构参数、元器件选型等进行了分析计算 ...
崔建业 +4 more
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TMRT observations of 26 pulsars at 8.6 GHz
, 2017 Integrated pulse profiles at 8.6~GHz obtained with the Shanghai Tian Ma Radio Telescope (TMRT) are presented for a sample of 26 pulsars. Mean flux densities and pulse width parameters of these pulsars are estimated. For eleven pulsars these are the first
Du, Yuan-Jie +20 more
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Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT Harnessing solar energy for self‐heating presents an effective strategy to suppress surface ice formation. In this paper, we fabricated nano‐silver‐modified multilayer graphene sheets (Ag@MGs) that integrate photothermal and superhydrophobic properties for anti‐icing applications.
Yihan Zhang +7 more
wiley +1 more source
不同电压等级直线塔线路覆冰拉力值预警模型及核密度概率估计研究
Dianci bileiqi, 2022 针对目前电力部门根据线路覆冰比值进行融冰的业务需求，且目前覆冰比值均是根据在线监测终端拉力值反算出冰厚，但计算模型所涉及到参数较多，导致模型准确率依赖性较高，同时国内外缺乏利用拉力值对线路覆冰预警研究。因此，从线路力学角度出发，建立冰期直线塔线路受力分析模型，以至到达根据拉力阈值直接判断线路融冰预警、启动融冰条件的目的。首先按照覆冰比值0.3、0.5两种条件对各电压等级线路拉力阈值进行计算，并对拉力比值进行定义；其次采用核密度概率估计算法，分析拉力比值统计学规律 ...
吴建蓉 +4 more
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International Journal of Urban and Regional Research, Volume 50, Issue 1, Page 191-220, January 2026.Abstract Henry George advocated for capturing land value increases for public ends. The active approach of public authorities organizing and financing land development can help capture higher land value increases, as Hartman and Spit indicate. However, this approach hardly happens in developing countries, where the coalition of private developers and ...
Nannan Xu
wiley +1 more source
A Study of EU’s Participation in Arctic Governance [PDF]
, 2016 欧盟与北极在地缘、经济等有多方面的关联性，对北极的资源价值有着极大的利益诉求。2007年，欧盟以海洋问题切入北极事务，经过2008年、2012年的两次正式的北极政策确立和完善，欧盟初步形成政策连贯、目标明确、执行性强的北极战略。欧盟的北极政策中明确了对北极治理的规划和目标，既致力于从北极公共问题如气候、海洋、环境、原住民等问题发挥自己的影响力，保障北极的生态系统平衡和可持续发展，也积极谋求在北极治理上的地位，增强在北极问题上的话语权，在北极开发治理上成为利益共享者。 总体来说 ...
王慧杰
core
Multi-Time Scale Optimization Strategy for New Distribution System Oriented to Photovoltaic Consumption and Low Carbon Demand Response of Ice Storage Air Conditioning Groups [PDF]
ObjectivesIn view of the limitations of the traditional distribution network demand response model in regulating the flexible and controllable resources on the load side, especially ignoring the unique and efficient resources such as ice storage air ...
GUO Junhong +5 more
core +1 more source
Study on Phase-change Cold Storage Characteristics of Al_2O_3-H_2O Nanofluids [PDF]
, 2010 Al2O3-H2O nanofluids with uniform dispersancy were prepared in which a spot of Al2O3 nanoparticles with a particle size of 20nm suspended in water and the dispersant and supersonic oscillating were added.The cold storage characteristics of the nanofluids
吴淑英, 朱冬生, 李华, 杨硕
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Dianci bileiqi, 2016 输电线路覆冰是我国常见的自然灾害,危害极大,而现有融冰方法均存在各自的局限性。对此,提出一种基于串联谐振原理的工频谐振融冰方法,并分析了此方法的融冰原理及融冰接线方式;计算了典型导线的工频谐振融冰电流并同直流融冰法作了对比分析;定量分析了融冰中出现的谐振电压并提出电容器组串联均压和改变融冰接线方式降压的办法;最后简要介绍工频谐振融冰装置关键设备的构成。研究结果表明:与直流融冰相比,本方法融冰效率更高;通过控制融冰线路长度和融冰源接入方式可使融冰谐振电压处于线路绝缘水平范围内;融冰电源容量小,构造简单 ...
荆群伟, 周羽生, 刘亮, 罗屿
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Gaoya dianqi, 2020 在覆冰导线高频激励融冰温度场的分析与计算中,局部对流换热对温度场及高频激励融冰模型有很大影响。对此,文中分析了高频融冰过程中的热量损失和对流换热的影响因素,通过Ansys有限元软件对高频激励融冰模型的电磁场和热分析与计算,揭示了局部对流换热对高频融冰模型温度场及其迎风侧和背风侧的影响,表明了局部对流换热使导线背风侧覆冰先融化脱落,迎风侧覆冰后融化脱落。覆冰导线外表面的温度随对流换热的系数增大而下降,下降速度随对流换热系数增大而减缓。该研究成果有利于进一步改进和优化高频激励融冰计算模型。
袁肖雷 +6 more
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