Results 41 to 50 of about 30,773 (189)
Rare Metals, EarlyView.ABSTRACT The evolution of the γ′−Ni3(Al, Ti) phase in superalloys is governed by a coupled coalescence‐ripening mechanism driven by elemental diffusion. In this study, thermal exposure experiments were performed at 750°C and 800°C for durations ranging from 100 to 20,000 h.
Zhaotian Wang +5 more
wiley +1 more source
基于主成分分析和反向传播神经网络相结合的金属氧化物压敏电阻故障诊断分析
Dianci bileiqi, 2019 准确诊断金属氧化物压敏电阻故障对电力系统安全运行十分重要。为有效提高故障诊断率,本文提出基于主成分分析与反向传播神经网络相结合的故障诊断算法。对于MOV故障数据指示指标,利用主成分分析进行降维,降低原始指标间相关性,最后利用反向传播神经网络对所选主成分进行诊断。试验结果表明:相对于反向传播模型,PCA-反向传播模型诊断误判率下降了3%,模型运行时间降低了267 s。有效降低MOV误判率,简化了反向传播网络结构,提高网络收敛性和稳定性。
王伟, 虢韬, 杨恒
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Zhejiang Daxue xuebao. Lixue ban, 2017 2015年1~12月在温州市区采集448个PM2.5样品，采用离子色谱法分析PM2.5中9种水溶性离子(、Cl-、Na+、K+、Ca2+、Mg2+和F-）的浓度，研究其污染特征、化学组分和来源.采样期间9种水溶性离子总浓度为39.97 µg • m-3，和占所测水溶性离子总量的(40.19±10.04)%.离子总浓度的季节变化特征为冬季>春季>秋季>夏季，从空间分布上看，多数季节市站采样点PM2.5中离子总浓度低于南浦、龙湾和瓯海采样点.相关性分析结果显示，PM2.5值与、Ca2+、Na+、K+、Cl-、
GELinlin(葛琳琳) +7 more
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Interface Issues of Inorganic Solid‐State Electrolytes in Secondary Magnesium Batteries
Rare Metals, EarlyView.ABSTRACT Solid‐state magnesium batteries (SSMBs) have gained significant attention as promising candidates for next‐generation safe energy storage systems because of the abundance of magnesium (Mg) in the earth's crust, superior energy density, and inherent nonflammability.
Jiren Wang +9 more
wiley +1 more source
New egogram developed by Web survey [PDF]
, 2017 Based on the web survey，new Egogram has been developed. From a preliminary survey of college students (N=117) and two web surveys (N=564, 1072)，reliability (internal consistency，temporal stability) and concurrent test validity were confirmed.
Ichimura Miho +7 more
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Rare Metals, EarlyView.ABSTRACT Efficient and durable bifunctional electrocatalysts are vital for scalable water electrolysis. Here, we realize cobalt‐vacancy (Covac) engineering in CoFeP supported on N,P‐codoped carbon nanocages (Co1‐vacFeP/NPC) through a simple route comprising a CoFe Prussian blue analog precursor, phosphidation–pyrolysis, tannic‐acid etching, and a ...
Yuan‐Liang Yuan +6 more
wiley +1 more source
Shuitu Baochi Xuebao, 2020 以陇西县600份土壤全氮含量数据为基础，应用地统计学研究陇西县土壤氮素的空间分布特征并计算了该区域的氮储量，采用相关性分析、主成分分析等方法探讨了影响全氮空间分布的影响因素。结果表明，陇西县土壤全氮含量为（0.734±0.306） g/kg，变异系数属于中等程度变异；氮密度平均值为0.091 kg/m2，氮储量为7.6×106 kg，其中0—10，10—30，30—50 cm土层氮储量分别占到0—50 cm土层氮储量的35.97%，7.06%，56.97%。陇西县土壤全氮含量及氮储量空间分布相似 ...
任建新 +4 more
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Zhejiang Daxue xuebao. Lixue ban, 2016 为在方案设计初期与工程造价相关信息很少的条件下，准确快速地预测住宅工程造价，在分析既往相关理论和方法优劣的基础上，选取支持向量机构建住宅工程造价预测模型，并通过主成分分析对原始数据进行降噪处理.选取住宅工程造价预测指标集与样本，对输入指标的数据进行主成分分析，消除指标相关性的同时对原始数据降维，将处理后的数据分别导入到“标准支持向量机”和“最小二乘支持向量机”模型中进行训练和预测，并对预测结果进行对比分析，选取较为合理的预测模型，通过参数寻优进一步优化预测效果.所构建预测模型的相对误差均控制在±7%以内，
QINZhongfu(秦中伏) +3 more
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Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Organic phosphorus mineralization is a critical process in the phosphorus cycle, governing phosphorus bioavailability for plants. The PhoD gene, which encodes the key enzyme alkaline phosphatase, serves as a valuable biomarker for this process.
Sandhya Mishra +3 more
wiley +1 more source
野生动物学报, 1997 本文通过粪便分析对甘肃兴隆山保护区食肉兽的食性及与马麝的关系进行了初步研究．粪便直径分析表明，该地区食肉兽主要为狐和豹猫．粪便内含物分析结果表明，啮齿类和鸟类出现的频率分别为８１．６％～８８．４％和２１．１％～３８．６％，马麝成体在４～５月很高（１７．６％），幼麝在出生期高达２１．１％．分析认为兴隆山食肉兽对马麝的捕食主要在马麝的幼仔期．
高志千, 康发功
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