Results 21 to 30 of about 733,350 (164)
Microstructure Engineering Toward High Cost‐Effective Nd–Fe–B Sintered Magnets: A Review
ABSTRACT Nd–Fe–B sintered magnets, critical for enhancing electromechanical conversion efficiency and operational stability in wind turbines and electric vehicle drives, are prized for their outstanding coercivity, high remanence, and superior maximum energy product.
Dongmin Zhang +5 more
wiley +1 more source
针对电网电压出现不平衡会导致储能变流器(power conversion system,PCS)输出的有功功率波动、无功功率波动和三相电流峰值越限问题,文中提出了一种考虑电流峰值限制的储能变流器协调控制策略。首先分析了传统控制策略在电网电压不平衡下的局限性;其次利用瞬时功率理论与加权思想,在αβ两相静止坐标系上实现抑制有功功率波动与抑制无功功率波动的协调控制;然后在上述基础上,加入一种电流峰值限制方法,能在PCS进行协调控制的同时保障输出的三相电流峰值不越限 ...
谭丽平 +8 more
doaj
Enhanced Magnetocaloric Effect in Tb‐Co‐Ni Magnets via Chemical Pressure
ABSTRACT Magnetic refrigeration materials are significantly needed in versatile modern industries, including scientific research, aerospace, and health care, due to their potential applications in gas liquefaction and storage. Herein, a significantly enhanced magnetocaloric effect with a suitable operation temperature range of 53–114 K and a giant ...
Lei Xi +11 more
wiley +1 more source
研究了基于深度强化学习算法的自主式水下航行器(AUV)深度控制问题。区别于传统的控制算法,深度强化学习方法让航行器自主学习控制律,避免人工建立精确模型和设计控制律。采用深度确定性策略梯度方法设计了actor与critic两种神经网络。actor神经网络给出控制策略,critic神经网络用于评估该策略,AUV的深度控制可以通过训练这两个神经网络实现。在OpenAI Gym平台上仿真验证了算法的有效性。
王日中, 李慧平, 崔迪, 徐德民
doaj
ABSTRACT Biodegradable zinc (Zn)‐based materials are considered promising candidates for orthopedic applications because of their favorable mechanical properties, controllable biodegradability, and good biosafety profiles. However, their clinical translation is limited by early‐stage corrosion‐induced cytotoxicity and inflammation, as well as ...
Jinlong Mao +9 more
wiley +1 more source
ABSTRACT In electrocatalysis, traditional single‐atom catalysts (SACs) face challenges in achieving coordinated control of reaction pathways due to limitations such as single local energy levels and carrier recombination. By introducing an additional defect structure, it is possible to break the electronic structure symmetry, thereby activating SACs ...
Juanjuan Huo +8 more
wiley +1 more source
ABSTRACT Bimodal grain structure (BGS) demonstrates significant potential in synergistically optimizing the strength and plasticity of magnesium alloys. Acquiring the desired BGS consequently became a critical challenge. This study took the Mg‐9Gd‐1Zn‐0.5Zr (wt%, VZ91K) alloy as its subject. From the perspective of BGS formation mechanisms, it suggests
Shuai Yuan +5 more
wiley +1 more source
针对多联机常规的制热控制策略导致系统运行不稳定的特性,提出新的控制策略,建立了压缩机输出比控制模型和压缩机切换控制模型,设计一套10HP数码涡旋多联机系统进行验证。控制模型中以一个周期时间内排气压力的平均值作为当前压力值按照给定的目标压力区域来调节压缩机输出比,并给出了控制模型中的目标压力基准值的确定原则。压缩机切换控制策略中,设置数码压缩机为优先级高的压缩机,调节其输出能力,直到100%输出比,再切换启动定频压缩机,有利于提高性能系数。实验证明这种控制策略对提高系统运行的稳定性 ...
肖洪海, 涂虬, 冯自平, 刘煜
core +1 more source
为了解决光伏发电在电网电压跌落过程中,逆变器两侧功率不平衡出现过电流和过电压的问题,设计了一种定功率跟踪控制的光伏并网低电压穿越策略。通过定功率跟踪控制对光伏阵列输出功率进行调节,根据电压跌落深度,合理给定功率参考值,控制光伏阵列的功率输出,实现交、直流侧功率的快速平衡,限制直流母线电压的增长。通过逆变器无功补偿控制,不仅能限制并网电流在安全范围内,还能够根据跌落深度提供无功支撑,有效地利用了逆变器自身的无功调节能力。结果表明,该策略能够抑制过电压和过电流,使系统具备一定的低电压穿越能力。最后 ...
董广凯 +4 more
doaj
ABSTRACT In conventional photoconductive detectors, the shared collection path for dark current and photocurrent imposes a fundamental compromise between noise suppression and signal responsivity. To break this trade‐off, we introduce a device architecture featuring a strategically integrated third electrode within a MAPbI3/Nb2CTx heterostructure. This
Yan‐Wei Lv +7 more
wiley +1 more source

