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Integrative Conservation, Volume 2, Issue 4, Page 165-175, December 2023., 2023 There is a lack of knowledge of which species and areas have a high risk of zoonotic disease spillover due to wildlife hunting and trade. We combined maps of hunting pressure, recent data sets on human‐shared pathogens, and trade volumes for 614 mammalian host species to map zoonotic disease risk from wildlife hunting and trade pantropically.
Jacqueline Choo +4 more
wiley +1 more source
Capacitor Voltage Ripple and Harmonics Analysis in MMC [PDF]
, 2023 [Introduction] The rapid development of VSC-HVDC provides practical support for MMC (Modular Multi-Level Converter) topology. Takes a half bridge MMC converter as an example, the relationship between steady-state capacitor voltage fluctuation, harmonic ...
Gang LI +4 more
core +1 more source
Encyclopedic Dictionary of Archaeology, 2020 摘要 大洋俯冲带之上是否出现弧岩浆岩是汇聚板块边缘研究的前沿, 而与弧系统演化相关的最重要的岩石学 问题是弧岩浆岩的起源. 作为弧岩浆体系中最重要的岩石类型, 弧玄武岩是揭示俯冲带地幔富集机制、壳-幔相 互作用等深部动力学过程最重要的“岩石探针”之一. 俯冲大洋板片释放的流体或发生熔融产生的熔体在不同深 度以不同比例交代地幔楔形成弧玄武岩的源区, 导致大部分弧玄武岩展示出富集大离子亲石元素和轻稀土元 素、亏损高场强元素和重稀土元素的特征, 而小部分玄武岩则显示高Nb或富Nb特征. 还有少量在弧区分布的玄
Jan W. Gooch
semanticscholar +1 more source
Improved sub-band JND model with textural decomposition and its application in perceptual image coding [PDF]
, 2014 In order to improve the accuracy of the just noticeable difference (JND) model in transform domain, an en-hanced JND model with a new method for contrast masking factor estimation was proposed. The image was decomposed and the textural image was used for
Cheng-dong LAN +4 more
core +1 more source
Gaoya dianqi, 2022 文中以500 kV张北柔直输电线路工程为研究对象，构建5因素3水平的L16(35)正交试验方案，利用PSCAD/EMTDC软件搭建感应电压与电流的仿真模型，分析了导线排列方式、交直流回路间垂直距离、直流极导线间水平间距、回流线等导线布置方案对带电回路在停运检修线路上感应电压与电流的多因素相互影响程度及规律。结果表明：交直流线路采用上下两层均平行布置时，各感应分量最小，且两极线间感应分量差值亦最小；回流线可降低检修线路上感应电压与电流约35%；影响静电耦合分量因素的因子主次顺序为：垂直间距、运行电压 ...
吴田 +4 more
doaj
Gaoya dianqi, 2021 作为直流输电系统最重要的设备之一,换流变压器的绝缘状态对直流输电系统的安全稳定运行起着至关重要的作用。其阀侧绕组不同位置需要承受不同交直流分量比例的复合电压。而现有研究主要针对1:1复合电压比例,其他电压比例研究较少。文中基于脉冲电流法与恒定电压法,建立了复合电压下油纸绝缘局放实验平台,研究了1:1、1:3、1:5和1:7交直流比例复合电压下针板电极有油隙模型、针板电极沿面强/弱垂直分量模型的局放起始放电电压、谱图特性和放电典型特征。结果表明:沿面强垂直分量模型的起始放电电压明显低于弱垂直分量模型 ...
张永武 +6 more
doaj
柔性直流并入城市电网后对换流站近区短路电流的影响研究 [PDF]
, 2023 大型城市供电电网短路电流已经接近断路器遮断容量，柔性直流接入系统后，会在故障期间提供工作电流，导致交流系统短路电流超标，柔性直流输送功率受限。从柔性直流内外环控制方式及交流系统短路电流计算原理出发，分析得出柔性直流短路电流的幅值和相位对并网点的短路电流影响均较大，其中幅值受外环电流限幅环节的影响易于控制，因此需着重对相位进行控制。基于此提出了一种降低柔性直流输电换流站两端PCC点短路电流的控制策略。以厦门柔性直流工程为例，开发了交直流混合模型，与实测波形对比验证了模型的正确性。通过对不同类型故障下 ...
寇龙泽, 朱琳, 范征, 谷怀广
core +1 more source
Gaoya dianqi, 2022 为提升柔性直流输电系统稳定性，一般在柔直单元逆变侧设置辅助直压环，当正、负极间直流电压跌落到一定阈值时，直流电压由逆变侧控制，整流侧输送固定有功功率，并为交流系统电压提供无功功率支撑。然而受环境或自身质量影响，高压直流分压器有可能产生故障，进而引发直流电压波动。当整流侧测量异常偏高时，引起逆变侧辅助直压环起动作，导致此时系统的整流侧和逆变测两端均控直流电压，直流系统输送功率失控，甚至发生反转。针对这一风险，文中基于RTDS的异步联网仿真平台，通过对测量值乘一个异常系数k来模拟直流电压电流测量异常 ...
罗炜, 谢超, 陈培龙
doaj
A Wireless Multi-Objective Power Sharing Method for Energy Storage System in DC Micro-Grid Considering Oscillatory-Type Power [PDF]
As the construction of new power systems, DC microgrids will become an important part of the distribution network. As AC load connecting to DC microgrids, the oscillating power will enter the DC system, which affects the power distribution of energy ...
LU Gang +4 more
core +1 more source
All-optical pattern matching system of 42 Gbit/s 4-bit BPSK signals and its demonstration for optoelectronic firewall [PDF]
, 2022 To achieve the all-optical pattern matching for optoelectronic firewall which could process high-speed optical signals efficiently, a BPSK all-optical pattern recognition system with the data rate up to 42 Gbit/s was proposed and demonstrated by ...
Lei GUO +5 more
core +1 more source