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The Photogrammetric Record, Volume 37, Issue 180, Page 366-384, December 2022., 2022 Abstract Registration of 3D spatial data and models is a fundamental task in applications such as mapping, positioning and virtual/augmented reality. Most of the existing 3D registration methods such as iterative closest point (ICP) and recent learning‐based methods are dedicated to point cloud registration, and rely heavily on point‐wise ...
Yuan Zhao +3 more
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Do diverse landscapes provide for effective natural pest control in subtropical rice?
Journal of Applied Ecology, Volume 57, Issue 1, Page 170-180, January 2020., 2020 Our findings question the cost‐effectiveness of current chemical‐based pest management in farming, and highlight opportunities for more ecologically based pest management strategies based on the widespread activity of natural enemies. Pest damage and biocontrol, however, are largely independent from the landscape context, which might be due to the ...
Yi Zou +8 more
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Integrative Conservation, Volume 3, Issue 4, Page 312-329, December 2024.Biosphere reserves aim to protect global biodiversity alongside social and economic development. In the Cape Floristic Region, biosphere reserves are an effective conservation approach to protect arthropods against habitat transformation in this biodiverse region.
Michael J. Samways +3 more
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Eyes on nature: Embedded vision cameras for terrestrial biodiversity monitoring
Methods in Ecology and Evolution, Volume 15, Issue 12, Page 2262-2275, December 2024.Abstract We need comprehensive information to manage and protect biodiversity in the face of global environmental challenges, and artificial intelligence is required to generate that information from vast amounts of biodiversity data. Currently, vision‐based monitoring methods are heterogenous; they poorly cover spatial and temporal dimensions, overly ...
Kevin F. A. Darras +11 more
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Gaoya dianqi, 2018 为了研究功率模块数不对等条件下柔性直流换流阀阀段运行试验方法,文中通过分析阀段运行试验过程中进行模块旁路试验的过程,建立了试验回路电流和模块电压的数学计算模型,提出了功率模块数不对等条件下的阀段运行试验方法。利用PSIM仿真软件对试验方法进行了仿真,并在实际的阀段运行试验中应用了该方法。仿真与试验结果表明,文中设计的试验方法可以实现功率模块数不对等条件下MMC阀段运行试验测试,满足试验要求。
田鸿昌 +5 more
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Gaoya dianqi, 2014 笔者提出了一种新型无功补偿装置组合,即基于固定电容器（FC）+磁阀式可控电抗器（MCR）无功补偿装置,然后对其结构的工作原理和补偿原理进行了详细的说明,并且详细地说明了新型无功补偿装置的信号采集模块、晶闸管驱动模块、光纤传输模块,键盘和液晶显示模块以及相应的软件编写流程。为了验证新型无功补偿装置的补偿效果,文中利用MATLAB的软件搭建10 kV电网系统,通过利用新型无功补偿装置将系统的功率因数补偿到设定的功率因数,文中给出了相应功率因数补偿跟踪仿真波形 ...
张健华, 张春梅, 黄兆
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混合型MMC换流器过调制下的热-电应力分布特性研究 [PDF]
全球能源互联网, 2018 全/半桥子模块混合型模块化多电平换流器（modular multilevel converter，MMC）由于具备直流故障穿越能力并兼顾了制造成本，成为当下柔性直流输电领域的研究热点之一。全桥子模块具备负电平输出能力，混合型MMC可以提升电压调制比，运行在过调制状态，提升运行效率。但是混合型MMC在过调制运行工况下的电流、热应力分布特性尚不明晰，为此针对混合型MMC在过调制下的全/半桥子模块开关器件的电流应力及热应力展开研究。通过分析混合型MMC在过调制下的工作原理和特性 ...
盛景, 董玉斐, 李武华
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Gaoya dianqi, 2019 针对并联多模块电流型双向直流—直流变换器,为了实现功率组合的灵活性及模块化设计,提出了一种改进模式的分布式控制策略。该策略通过采样高压侧电压和低压侧电流,实现下垂控制,同时采用电压补偿技术,改善了高压侧电压调整率。搭建了二台功率各为1.5 kW的样机进行了实验验证。实验结果表明:该方法无论在静态还是动态下,可以实现模块之间良好的功率均分;同时改善了电压调整率并能实现热插拔功能。
宋波, 杨峰, 易航
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Gaoya dianqi, 2017 为了研究功率循环下键合引线的疲劳寿命,提高IGBT模块的可靠性,文中提出了一种基于壳温的键合引线寿命预测方法。首先对IGBT模块进行功率循环测试,探究了键合引线的疲劳失效机理;然后建立IGBT模块的电—热—结构强耦合模型,分析了模块在功率循环载荷下的电、热、结构特性。依据键合引线的应变情况和实验测得的疲劳曲线,评估键合引线的疲劳寿命,并在壳温基础上建立了其寿命预测模型,对比测试结果验证了该模型的准确性;最后提出了铜键合引线的改进方案。根据易测量的壳温来确定键合引线的使用寿命,提前更换器件 ...
赵旭州, 朱戈, 吴馨
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Gaoya dianqi, 2019 目前,国内外对模块化多电平换流器（modular multilevel converter,MMC）的运行特性的研究主要集中在换流器环流产生机理及其抑制、换流器输出电压及电流谐波特性等方面的分析,未对换流器功率模块电容对换流器调制度的影响进行过多研究。文中从换流器的基本原理出发,详细分析了功率模块电容对换流器调制度的影响,分析表明换流器桥臂中的n次谐波电流会在功率模块电容上产生n-1、n、n+1次电流谐波,进而在功率模块电容上产生n-1、n、n+1次电压波动 ...
任成林 +5 more
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