Results 21 to 30 of about 33,590 (182)
Dianci bileiqi, 2017 为研究山东电网绝缘子表面污秽成分的特点,选取不同运行环境、不同电压等级和不同电场的绝缘子,采用离子色谱等方法分析污秽中的主要成分。研究结果表明:自然降水的冲刷效果,造成绝缘子表面难溶性盐CaSO4的富集特性比易溶性盐显著;重污区绝缘子污秽中主要成分含量明显高于其他环境;相同运行环境,500 k V绝缘子污秽中主要离子成分的含量明显高于220 k V、110 k V绝缘子;直流电场对污秽的吸附能力比交流电场强,但对污秽成分的影响不大。采用富集因子分析方法,分析了污秽中主要金属元素Ca的来源 ...
刘嵘 +7 more
doaj
Applying Statistical Methods to Develop a Better Vocabulary List [PDF]
, 2007 これまでに数多くの学習語彙表が開発されているが，より良い語彙表を作るために，既存の語彙表における情報を統計的手法によって統合しているような研究はほとんどない。本研究では，基礎語の抽出のために，いくつかの語彙表などにおける語彙の特徴指標を統合し，より良い学習語彙表を開発するための統計的手法の検討を行うことを目的とした。まず，中学校主要英語教科書をコーパス化したものの頻度を基にした語彙表を作成し，いくつかの既存の語彙表や語に対する親密度，語の長さなどを語の特徴指標とし ...
Mizumoto Atsushi, 水本 篤
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Conservation Biology, EarlyView.Abstract Human development is a driver of global change and a major threat to biodiversity. Protected areas maintain and support biodiversity, but outside stressors, such as climate change and land use change, can negatively influence natural resources within protected areas.
Leah J. Rudge +2 more
wiley +1 more source
Dizhen xuebao利用机器学习中的主成分分析法（PCA）提取了2022年泸定MS6.8地震的M5.0余震（2022年10月22日）的特征主成分时程，对泸定MS6.8主震的地震动时程进行模拟。在此过程中，将主震目标台站的地震动峰值加速度和反应谱作为约束条件，利用粒子群优化（PSO）算法计算特征主成分时程的组合系数。结果显示模拟结果与真实记录较为一致。这表明：利用机器学习算法能够通过提取余震的特征主成分时程对目标地震进行模拟；在进行小区域地震动模拟时 ...
Kai Chen, Hua Pan
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Scenarios and strategies for future‐proofing ecosystem management under climatic novelty
Conservation Biology, EarlyView.Abstract Climate change is driving unprecedented declines in dominant, habitat‐forming foundation species across marine and terrestrial ecosystems globally. As climatic novelty becomes the norm, ecosystem reassembly will become increasingly common. Predicting and understanding these transitions, and their implications for future ecosystem functioning ...
Lauren T. Toth +14 more
wiley +1 more source
Nonlinear predictions in regression models based on kernel method [PDF]
, 2009 Thesis (Ph. D. in Engineering)--University of Tsukuba, (A), no. 5170, 2009.7.24Includes bibliographical references (p.
Wibowo Antoni
core
Drivers of bat researchers’ intent to adopt field hygiene practices
Conservation Biology, EarlyView.Abstract Infectious disease is a growing threat to wildlife, with zoonotic transmission most likely at the human–wildlife interface. One underappreciated activity at this interface is fieldwork with wild animals, but associated risks can be mitigated through field hygiene (FH) practices, such as using personal protective equipment and other appropriate
Joanna L. Coleman +6 more
wiley +1 more source
Gaoya dianqi, 2018 为了进一步提高基于油中溶解气分析的变压器故障诊断准确率,提出了一种基于模糊聚类和主成分分析的故障诊断方法。该方法首先利用模糊C均值聚类方法对搜集的DGA样本集进行聚类分析,将聚类中心矩阵作为标准故障谱。然后采用改进型主成分分析方法精简样本矩阵信息,通过计算样本主成分间欧拉距离确定故障类型。通过实例验证证明本文方法能有效识别故障类型,且较IEC比值法、改良三比值法等具有更高的准确率。该方法为变压器故障诊断提供了新思路,具有一定的实际应用价值。
覃煜, 黄慧红, 方健, 陈雁
doaj
International Journal of Applied Linguistics, EarlyView.ABSTRACT Although the use of AI technologies (e.g., chatbots and automated writing evaluations (AWE)) has gained considerable attention in language learning fields in recent years, how AI technologies have been designed and implemented in language learning education, as well as their effectiveness, is understudied.
Shen Qiao +2 more
wiley +1 more source