Results 41 to 50 of about 990,138 (190)
Rare Metals, Volume 45, Issue 11, November 2026.ABSTRACT Silicon carbide (SiC) is an ultra‐hard ceramic material and is intrinsically difficult to sinter. Pressureless solid‐state sintering (PS) typically requires high temperatures exceeding 2200°C and a prolonged heating cycle, whereas liquid‐phase sintering lowers the processing temperature at the expense of high‐temperature mechanical performance.
Meicen Fan +5 more
wiley +1 more source
Gaoya dianqi, 2018 对高压断路器动作过程中状态特征参量的提取与分析是状态识别与故障诊断的关键。高压断路器分合闸过程中的触头行程曲线蕴含着反映其内部机构机械状态的丰富信息。然而,仅依靠常规的时间和速度等参量无法对高压断路器的机械状态进行准确识别。文中提出了一种基于最优特征向量分类的高压断路器机械状态识别方法,通过计算各个特征与状态分类之间的互信息,根据最大相关最小冗余的准则筛选出最优特征子集,然后基于最优特征量构建支持向量机（SVM）,利用分类准确度进行评价,确定出最优的特征向量和分类模型。对实验数据的分析结果表明 ...
杨景刚 +5 more
doaj
, 2009 针对现有识别方法在特征选择的局限性,借鉴人脸的特征,提出一种融合几何特征向量的三维人脸识别方法。该方法提取了人脸面部具有相当代表性的特征点,从而得到一个相对完整的几何特征向量组用于识别匹配工作。实验结果表明,该方法改进了识别算法 ...
欧阳江帆, 李晓雯, 肖庆云
core
World Food Policy, Volume 12, Issue 2, November 2026.ABSTRACT Household food expenditure continues to be a key factor in ensuring the realization of the Human Right to Adequate Food. Particularly in Brazil, access to food can be limited by economic constraints in vulnerable families, especially among farming families, who have been more vulnerable to food insecurity in recent years in the country.
Lucas de Almeida Moura +3 more
wiley +1 more source
四川大学学报. 自然科学版, 2005 在合成孔径雷达(SAR)图象中,需要对其中的人工和自然目标进行识别和分类,目标的特征提取是自动目标识别系统中的关键部分.一般图象的特征会采用颜色、纹理、形状等特征量.在SAR图象中,由于存在大量的背景噪声、目标边界模糊等问题,造成以上特征量在分类时往往不能达到很好的分类效果.作者提出了一种典型目标特征提取和分类识别方法.这种方法基于SAR成像的原理,在图象灰度阈值分割后做粗搜索分别提取灰度特征,椭圆矢量特征,以及栅格特征,然后进行SAR图象典型目标的分类识别.实验表明,这种方法效果较好.
夏昕, 罗代升, 罗峰, 林宏津
doaj
Learning Styles, Engagement and Anxiety in AI‐Mediated Writing: A Multimodal Feedback Study
International Journal of Applied Linguistics, Volume 36, Issue 4, Page 3269-3281, November 2026.ABSTRACT Artificial intelligence (AI) tools now permeate English academic writing. However, evidence on how feedback modalities align with student differences and with psychological mechanisms remains limited. Prior work often reduced learning styles to simple matches with delivery modes and treated learning engagement and writing anxiety as peripheral.
Yi Ren +3 more
wiley +1 more source
Gaoya dianqi, 2015 击穿电压是表征发电机定子线棒主绝缘老化状态的特征参量,是影响发电机寿命的直接原因,笔者设计了额定电压为8.5 kV的环氧云母绝缘板材并进行加速热老化试验,通过分析主绝缘板材特征参量的变化趋势,结合击穿电压与特征参量有效性判别,得到能有效表征主绝缘击穿电压的实用特征参量组,并采用BP神经网络滚动式预测方式对主绝缘击穿电压预测,结果表明,该特征参数组Qmax、△C、C、△tanδ、tanδ能有效地用于主绝缘击穿电压预测。
刘红文 +7 more
doaj
, 2008 独立分量分析是一种有效的人脸特征提取方法。考虑到人脸样本的对称性,本文采用对称独立分量分析的方法对人脸样本进行特征提取。为了提高独立分量分析法表征人脸特征空间的能力,本文采用遗传算法对特征空间进行选择优化,获得最优的人脸特征子集。仿真实验表明 ...
陈岚峰, 李娜, 赵乾, 刘莹
core
, 2021 本发明涉及光谱分析领域，具体是基于互信息特征筛选PLS的LIBS铁矿浆定量分析方法。针对数据存在噪声和光谱数据维度过高带来的问题，提出一种基于互信息特征筛选偏最小二乘的LIBS的定量分析方法以提高矿浆品位分析精度。具体步骤为：(1)计算训练样本每列特征与标签的互信息量；(2)训练集中去除互信量为0的a个特征；(3)测试集保留与训练集剩余特征相同的特征列；(4)利用确定的特征个数，建立PLS模型，通过训练集的解释方差和均方误差来确定主成分个数。本发明提供了一种降低数据维度并有效选出光谱数据特征的方法 ...
齐立峰 +4 more
core +1 more source
Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT To achieve high‐value utilization of spent catalysts, we recovered copper (Cu) from Cu‐bearing spent catalysts via acid‐base leaching to fabricate CuO and systematically studied how calcination temperature affects their microstructure and humidity‐sensing performance. Characterizations show that CuO‐500 (calcined at 500°C) has a large specific
Cong Liang +9 more
wiley +1 more source