Results 81 to 90 of about 1,133,635 (178)
, 2001 GaP:N绿色LED发光效率的提高有赖于对其结构参数的优化。根据载流子分布的连续性,由泊松方程自洽求解,得出了半导体n~--n结势垒分布的计算方法。在此基础上,计入n~-区内的电位降,计算了商用发光二极管p~+-n~-n结构的势垒分布 ...
赵普琴 +3 more
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Gaoya dianqi, 2020 空气开关柜是电网中运用最多的开关设备,长期温升过高会导致绝缘性能和机械性能的退化,甚至人员伤亡事故。为分析空气开关柜发热故障的温度分布特性,利用有限元仿真软件建立1∶1模型,进行电磁—流—热多物理场耦合仿真。模拟分析不同热故障,空气开关柜内部气体流速、内部器件表面温度分布、内部温度场分布和外壳温度分布的情况,总结不同热源功率下的分布规律,为基于开关柜表面温度场分布,判定开关柜内部故障奠定理论基础,并提供仿真借鉴。
苏毅 +4 more
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Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT An ultra‐high as‐deposited tensile strength of 1408 MPa—the highest reported value for laser‐directed energy deposition (L‐DED) fabricated Ti2AlNb alloy—is achieved in this study. The as‐deposited microstructure consists of coarse B2 grains with a high density of fine acicular O phase precipitates within the grains, along with a brittle α2 ...
Ximiao He +7 more
wiley +1 more source
Dianci bileiqi, 1990 影响无间隙金属氧化物避雷器电压分布不均匀的主要因素是杂散电容和阀片本身电容的分散。后者往往被忽略,导致不正确的结果。用光纤—电流法测量电压分布不均匀系数K值时,电流分布不能代表电压分布。对一台避雷器的实测结果不能代表同类避雷器电压分布最不均匀的情况。本文提出一种方法,对一台避雷器的实测结果经计算可得出该类避雷器电压分布不均匀系数K的最大值。
张雨时
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Asymptotic distribution of the product of trimmed sums(一类截断部分和乘积的渐近正态性)
Zhejiang Daxue xuebao. Lixue ban, 2007 对于取值为正的独立同分布且平方可积的随机变量X1，X2，…且有连续的分布函数，令Mn = max{X1，X2, …，Xn}，对某固定常数a>0，令，截断和Tn（a）= Sn — Sn(a），在X的分布满足中尾分布的条件时，截断和Tn(a)的乘积为渐近对数正态.
ZOUHai-lian(邹海连) +1 more
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Wildlife Letters, Volume 4, Issue 3, Page 139-148, September 2026.Asiatic black bears in Russia face conservation threats such as habitat destruction and fragmentation, which exacerbate food shortages caused by crop failures. This study explores an innovative approach to rehabilitating bears that abandon hibernation in mid‐winter due to extreme exhaustion by providing supplemental food near their den sites.
Sergey A. Kolchin +2 more
wiley +1 more source
Gaoya dianqi, 2010 采用有限元数值分析法,针对750 kV交流输电线路绝缘子片数及均压环配置,对绝缘子串电位分布进行了计算分析,比较了均压环均压深度、环径、管径及绝缘件介电常数对绝缘子电位分布的影响;对典型配置绝缘子"I"串进行了电位分布的测量研究,并将试验和计算的结果进行了对比分析。研究表明,均压环均压深度及环径对绝缘子电位分布影响较大,均压环管径及绝缘件介电常数对电位分布影响不明显;试验与计算的绝缘子最高分布电压百分比基本一致。
霍锋 +4 more
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Wildlife Letters, Volume 4, Issue 3, Page 118-130, September 2026.Many nocturnal animals are difficult to study because they are rarely seen, including nocturnal primates, galagos and pottos, in West Africa. Working with over 600 people in 52 villages in southern Guinea‐Bissau, we found that communities frequently recognized galagos by their red eyeshine and distinctive calls, while pottos were not known.
Chloe Chesney +6 more
wiley +1 more source
一种分布放大的取样光栅分布布拉格反射可调谐激光器结构，包括：一衬底；一n-InP缓冲层制作在衬底上；一InGaAsP下限制层制作在n-InP缓冲层上；一增益层制作在InGaAsP下限制层上；一InGaAsP上限制层制作在增益层上，其表面形成有取样光栅结构，该取样光栅光栅结构位于无源波导之上；一p-InP层制作在InGaAsP上限制层上；一p-InGaAsP刻蚀阻止层制作在p-InP层上；一上p-InP盖层制作在p-InGaAsP刻蚀阻止层上；一p-InGaAs接触层制作在上p-InP盖层上 ...
王圩 +4 more
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Dianci bileiqi, 1981 本文研究未上釉棒形抗折瓷件强度的理论分布,其分布遵循维布尔分布。各种不同因素的试验验证了理论分布的正确性。本文还对估计维布尔参数值的方法进行了讨论,且对大容量子样估计了均匀性系数m在一定置信水平下的置信区间。
马功勋, 刘长荣, 陶增炎
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