Subjects: Dynamic and Electric Engineering >> Electrical Engineering submitted time 2019-03-05 Cooperative journals: 《电气工程学报》
Abstract：针对变频空调用功率因数校正（PFC）电路中的电感在运行时存在局部过 热、温升较高的情况，本文采用电磁热耦合仿真对其进行了优化设计。通过有限元分 析，搭建了 PFC 电感三维电磁热场的仿真模型，利用电磁仿真计算得出 PFC 电感的 功率损耗，并将其作为热源进行了热场模拟。通过改变绕组的匝数和磁心的尺寸，模 拟了四组不同的设计方案，分别进行了磁场 - 热耦合分析，从中给出了优化设计方案。 实际运行表明，优化后的 PFC 电感有效降低了温升和损耗，设计方法对于其他电感器 件的设计具有参考价值。
Subjects: Dynamic and Electric Engineering >> Electrical Engineering submitted time 2019-03-05 Cooperative journals: 《电气工程学报》
Abstract：针对变频空调用功率因数校正（PFC）电路中的电感在运行时存在局部过 热、温升较高的情况，本文采用电磁热耦合仿真对其进行了优化设计。通过有限元分 析，搭建了 PFC 电感三维电磁热场的仿真模型，利用电磁仿真计算得出 PFC 电感的 功率损耗，并将其作为热源进行了热场模拟。通过改变绕组的匝数和磁心的尺寸，模 拟了四组不同的设计方案，分别进行了磁场 - 热耦合分析，从中给出了优化设计方案。 实际运行表明，优化后的 PFC 电感有效降低了温升和损耗，设计方法对于其他电感器 件的设计具有参考价值。
Subjects: Mechanical Engineering >> Other Disciplines of Mechanical Engineering submitted time 2018-06-15 Cooperative journals: 《电气工程学报》
Abstract： In view of the local overheating and the higher temperature rise of the inductance in the power factor correction (PFC) circuit of the inverter air conditioner during operation, the electromagnetic coupling simulation is adopted to optimize the design of the inductor. The three-dimensional electromagnetic thermal field simulation model of PFC inductor is established by the finite element analysis method. The power loss of each component of the reactor is calculated by electromagnetic simulation, and the thermal field is simulated as a heat source. By changing the number of turns and the size of the magnetic core, four different design schemes are simulated. The magnetic field thermal coupling analysis is carried out, and the optimal design scheme is given. The actual operation shows that the optimized PFC inductor effectively reduces the temperature rise and loss, and the design method is of reference value for the design of other inductors.
Subjects: Agriculture, Forestry,Livestock & Aquatic Products Science >> Basic Disciplines of Agriculture submitted time 2017-11-06 Cooperative journals: 《中国生态农业学报》
Abstract：针对近年来“林农生产争地争光”的问题, 以株行距为3 m4 m 南北行向栽植的枣树||冬小麦间作系统为研究对象, 大田条件下设置枣麦间作(JZ)和冬小麦单作对照(CK)两个处理, 以2013—2014 年生长季冬小麦光合生理参数和冠层光照强度为基础, 以两棵枣树的定植点连成1 条测定样线, 在样线上以距枣树的东(E)、西(W)距离为基准, 每50 cm 设置1 个测定点, 设E50 cm、E100 cm、E150 cm、E200 cm(W200 cm)、W150 cm、W100 cm、W50 cm 共7 个测定位置, 在不同调查时期测定各测定位置的冬小麦冠层光合有效辐射(PAR)并在冬小麦成熟期调查各测定位置上的产量。采用多项式回归和定区间积分等方法计算冬小麦分蘖期、拔节期、抽穗期、扬花期、灌浆期和成熟期冠层达到饱和PAR 的时长与时空窗, 探讨枣麦间作系统中枣树遮光对间作作物冬小麦冠层光照分布及产量的影响。结果显示, 间作系统中冬小麦冠层光照强度及产量整体呈现出不同的时空分布特征, 且相较于单作小麦系统均有一定程度的衰减。单作冬小麦冠层的饱和PAR 时空窗比间作处理大56.1%, 穗粒数、有效穗数、千粒重和产量分别比间作小麦高14.7%、15.9%、33.5%和53.0%。相对于单作对照, 间作物冬小麦整个生育时期内在距枣树E50~E100 cm、E100~E150 cm、E150~E200 cm、W150~W200 cm、W100~W150 cm、W50~W100 cm 处的冠层PAR 时空窗损失严重, 分别达92.5%、45.7%、7.0%、5.4%、10.9%、54.0%。冠层PAR 时空窗损失导致冬小麦减产, 在以上各处减产程度分别达46.2%、39.6%、26.3%、24.7%、32.4%和37.6%。故枣树遮阴程度的差异导致间作物冬小麦不同程度减产, 且间作巷道内西侧光照质量体优于东侧。这就要求在冬小麦扬花期后对枣树进行适当修剪, 且适当增加巷道东侧枣树株距, 以避免枣树新生枝徒长, 提高冬小麦冠层光合有效辐射截获量, 使间作系统获得更高产量。
Subjects: Library Science，Information Science >> Information Science submitted time 2017-11-05 Cooperative journals: 《智库理论与实践》
Abstract： [Purpose/significance]This paper discusses strengthening the construction of the new model of network security and informatization-based think tanks with Chinese characteristics. [Method/process]It analyzes the background of the topic by elaborating the new philosophy, the new positioning, the new system and the new mechanism of this new model. [Result/conclusion]In terms of the “new philosophy”, this paper discusses the built-in Chinese characteristics and the new think tank; as to the “new positioning”, it proposes three orientations: for the vision of building well-established cyber power, for the network development in the land, sea, air and space, for the synergy and integration of the international and domestic governance model and modernization of management capabilities; as for “new system”, it is on multi-level and has multi-themes of think tank systems based on the analysis of the present situation of professional think tanks; the new mechanisms is regarding the international exchanges and cooperation, independence and contention of the research, data driven research, talent pipeline development and collaborative innovation.
Subjects: Library Science，Information Science >> Information Science submitted time 2017-07-13 Cooperative journals: 《智库理论与实践》
Abstract：[目的 /意义]论述了加强中国特色新型网络安全和信息化专业智库建设的命题。[方法 /过程]分析了提出这一命题的背景,从建设中国特色新型网络安全和信息化专业智库的新理念、新定位、新体系和新机制四个方面进行了深入的分析阐述。[结果 /结论 ]其中新理念论述了中国特色和新型智库;新定位提出了三面向:面向建设网络强国的发展新愿景,面向陆海空天网五大发展新空间,面向统筹国际国内治理体系和治理能力现代化新目标;新体系在对专业智库现状分析的基础上,提出了形成多层次多类型多主题的专业智库体系的专业智库建设构想;新机制则提出了国际交流合作、独立和争鸣的研究、数据驱动型研究、领军人才培养、协同创新五项新机制。
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