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经济管理研究, 2020 随着新冠肺炎跨国传递范围和程度的加深，疫情可能会打破全球经济的脆弱平衡，如今疫情已经覆盖全球价值链的重要节点，尤其是经济全球化以来全球的供应链垂直一体化不断发展，欧美地区已经陆续出台停止除必需品以外一切经济活动的严格防疫措施。而如今中国在全球价值链中扮演的角色日益重要，在面临全球经济不景气的大环境下也难置身事外。因此，论文着重分析疫情对全球及中国经济的影响，并从金融开放视角提出相应的解决办法，以新思维引领新实践新发展，为后疫情时代中国经济高质量发展提供源源不断的活力。
从会 杨 +4 more
semanticscholar +1 more source
适用于直流配电网故障选线的电力电子变压器分步闭锁方案 [PDF]
, 2023 级联H桥型电力电子变压器（power electronic transformer with cascaded H-bridge，CHB-PET）是柔性变电站的重要组成设备之一，在直流配电网中具有重要作用。当CHB-PET低压直流侧发生双极短路故障后，故障电流上升速度快且幅值较高，易导致电力电子器件迅速闭锁，使低压直流电网保护难以准确获取故障信息。针对CHB-PET低压侧多分支直流配电网，提出一种基于PET分步闭锁的故障穿越策略。当检测到PET低压侧直流系统故障后 ...
于弘洋 +5 more
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An Intelligent Method for Pork Freshness Identification Based on EfficientNet Model [PDF]
, 2023 A method for measuring pork freshness based on images and the EfficientNet framework was established. A total of 2 500 images of pork with different freshness were collected as original dataset and processed by image enhancement to construct a new ...
LIU Chao, ZHANG Jiayu, QI Chao, HUANG Jichao, CHEN Kunjie
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Optimization Calculation Method of Injection Voltage and Series Converter Capacity for Unified Power Flow Controller [PDF]
, 2023 [Introduction] The application of UPFC (Unified Power Flow Controller) is to increase the transmission capacity of key sections, which mainly through the injection of a certain series voltage into the system and therefore divert the power flow of target ...
Jiefeng ZHONG +4 more
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Effect of heat input on the microstructure and mechanical properties of TIG welded-brazed magnesium / steel joints [PDF]
, 2016 A tungsten inert gas(TIG) welding-brazing technology using an Mg-based filler was developed for joining Mg alloys to steel. The effects of heat input on the microstructure and mechanical properties of Mg/steel joints were investigated.
HONG Miao, LIANG Xue-bo, YUAN Xin-jian
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Simulation analysis of the relationship between the sampling time and tracking error of the model predictive control in inverter [PDF]
, 2017 模型预测控制（Model Predictive Control,MPC）是电压型逆变器（Voltage Source Inverter,VSI）电流跟随控制装置定频调制的典型方法,得到了广泛的应用。论文使用统计的方法研究MPC的采样时间与跟踪误差（方差）的函数关系。该函数关系是研究和解决逆变器切换优化问题的基础。仿真结果可得出采样时间与跟踪误差呈线性关系的结论。Model Predictive Control （MPC） is a typical method of voltage source ...
吴奕锴, 吴靖南, 康文
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Gaoya dianqi, 2022 容性电流开断能力，特别是C2级开断能力，已成为断路器满足工程需求的关键指标，因开断过程中易发生重击穿故障而导致试验失败的风险较大，故需对其容性开断能力进行评估。基于容性电流特点，文中采用“恢复电压”及“最小临界电压”评估其开断容性电流能力，且“恢复该电压”低于“最小临界电压”时，断路器具有开断容性电流的能力。采用电场及气流场耦合分析方法，断路器开断性能进行评估，得到试验工况下“恢复电压”均小于“最小临界电压”，表明该断路器具有容性电流开断能力，顺利通过C2级试验验证，进一步表明采用“最小临界电压 ...
郭自豪 +8 more
doaj
Gaoya dianqi, 2023 直流断路器是交直流混合配电网组网的关键，然而在考虑技术经济性时，当前直流配电断路器仍沿用高压直流输电等级断路器拓扑方案的思路不再适用，亟需开发经济型直流开断技术，实现中压直流配电断路器成本和性能的平衡。文中针对交直流混合配电网直流侧故障电流经济高效开断这一关键问题，基于直流熔断器和强迫过零开断技术，提出一种基于熔断器的组合式直流开断方案，该方案采用直流熔断器与转移开关并联后再与直流负荷开关串联的形式，利用低成本的直流限流熔断器开断大电流，减轻直流负荷开关的开断要求，进而降低整机成本 ...
王昊晴 +4 more
doaj
Optimal Control of Residents’ Controllable Load Resources Considering Different Demands of Users [PDF]
, 2023 Optimizing the controllable load resources of residents on the demand side is a major aspect of virtual power plant (VPP). It is an important means to improve the utilization rate of new energy such as wind power and photovoltaic power, to achieve carbon
HUANG He +5 more
core +1 more source
Invulnerability of small-world network against cascading failure based on nonlinear load-capacity model [PDF]
, 2014 To investigate the invulnerability of small-world networks against cascading failure, an improved nonlinear load-capacity model was introduced. Under the rule of local weighted load redistribution, the influence of weight coeffi-cient, capacity ...
Jia-sheng WANG +3 more
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