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Ecological Solutions and Evidence, Volume 6, Issue 3, July–September 2025.Over the past three decades, a large number of natural wild soybean populations have been declining inexplicably or even have disappeared and their distribution area has significantly decreased in China, and population losses continue unabated. Therefore, this study investigated 20 herbaceous communities of wild soybeans in various habitats in ...
Ke‐Jing Wang, Xiang‐Hua Li
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Integrative Conservation, Volume 4, Issue 2, Page 116-119, June 2025.This study provides definitive evidence of wolf presence based on camera trap surveys conducted in Shangri‐La National Park, northwestern Yunnan, between 2022 and 2024. This remarkable rediscovery highlights the critical role that well‐managed national parks can play in facilitating the recovery of endangered species.
Yun Deng +10 more
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, 2020 针对飞行机械臂系统的接触力控制问题,本文首先从理论上证明了闭环无人机系统具有与弹簧-质量-阻尼系统一致的动态特性.基于飞行机械臂接触状态下力的分析,得到了无人机水平前向接触力与系统重力和俯仰角之间的动态关系,进而分析出接触力控制可以不使用力传感器来实现.根据阻抗控制思想,提出了飞行机械臂系统接触力控制方法,即通过同时控制位置偏差和对应姿态角度来实现接触力的控制.给出了单自由度飞行机械臂系统动力学模型,对应分析出系统的稳定性.开发了基于四旋翼飞行器的单自由度飞行机械臂系统,并进行了实际的飞行实验 ...
孟祥冬 +5 more
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Strengthening Amazon conservation through community‐based voluntary patrolling
Conservation Biology, Volume 39, Issue 3, June 2025.Abstract Globally, environmental crimes are a major threat to biodiversity and the livelihood of local populations. Community‐based protection of natural resources, which involves local people in surveillance and enforcement, is an important complement to the government‐led command‐and‐control policing approach.
Caetano L. B. Franco +8 more
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Functional Ecology, Volume 39, Issue 5, Page 1274-1287, May 2025.Read the free Plain Language Summary for this article on the Journal blog. Abstract Interactions between plants and soil microorganisms in the rhizosphere are vital for maintaining the nutrient cycle and stability of terrestrial ecosystems. Nitrogen, closely related to carbon (C) cycling and ecosystem productivity, undergoes transformation by soil ...
Ru Wang +9 more
wiley +1 more source
Dianci bileiqi, 2015 结合视频监控系统信号传输的特点,设计用于视频监控系统保护的电涌保护器（SPD）。主要目的是抑制来自线路故障、开关动作过电压以及在信号线路上感应到的暂态雷电过电压,从而保护后端电子通讯设备免受电涌冲击。详细介绍了SPD的设计方案,采用电源、控制、视频三合一结构,由气体放电管和瞬态抑制二极管组成两级保护电路,选用合适的退耦元件以满足多级保护的能量配合,并通过桥式电路减小电路中的分布电容。通过理论分析与试验表明,该SPD具有电涌抑制能力强,电压保护水平低,插入损耗小等特点。
王志翔 +4 more
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Conservation Biology, Volume 39, Issue 2, April 2025.Abstract Accelerating rate of human impact and environmental change severely affects marine biodiversity and increases the urgency to implement the Convention on Biological Diversity (CBD) 30×30 plan for conserving 30% of sea areas by 2030. However, area‐based conservation targets are complex to identify in a 3‐dimensional (3D) ocean where deep‐sea ...
Laetitia Mathon +19 more
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Gaoya dianqi, 2008 研究了葛南直流控制保护系统改造完成后遗留下来的一个隐患,分析了葛洲坝换流站一次双极停运事故的现象,根据绝对最小滤波器组不满足的条件,指出无功控制与交流滤波器保护配合不当是这次事故的主要原因,同时找出有功功率回降软件功能不完善之处,最后给出了相应的解决办法,为将来更好地实施直流控制保护系统国产化改造提供参考。
田庆, 王晓希
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Uncovering Xi Jinping's Policy Agenda: Text As Data Approach
The Developing Economies, Volume 63, Issue 1, Page 9-46, March 2025.How many agendas has Xi Jinping put forth and promoted since taking office in 2012, and what are the types of agendas? How much of political attention has each agenda received, and how has the allocation of attention changed over time? We utilize a dataset of presidential statements, speeches, and reports from 2012 to 2022 and employed automated text ...
Jaehwan Lim, Asei Ito, Hongyong Zhang
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Gaoya dianqi, 2012 笔者分析了天广直流控制保护系统改造完成后发生的3次双极线路保护动作事件,剖析其中直流线路突变量保护误动作的原因。根据天生桥换流站和广州换流站的实际录波和实际过程,结合厂家给出的突变量保护定值和整定思想,分析导致突变量保护误动作的因素。笔者给出了2个解决方案——降低低电压保护定值和增大突变量保护的动作延时,并经实践验证正确,为以后更好地实施直流控制保护系统国产化改造提供参考。
田庆
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