Results 21 to 30 of about 931 (139)
Gaoya dianqi, 2021 简便、快速和准确地评估直埋电缆群缆芯温升对于保证其可靠、安全运行,以及管理电缆群的实时负荷具有重要的现实意义。当直埋电缆群周围热媒介导热系数已知时,电缆本体和相邻电缆间均可以用线性方程表示其热过程,从而可以构建一个转移矩阵来实时估算电缆缆芯温升。利用有限元计算结果,获得电缆本体缆芯温升与发热样本数据组,以及相邻电缆间的发热与温升样本数据组,再利用数据拟合,获得缆芯温升与缆芯损耗、介质损耗、金属套损耗,以及相邻电缆损耗之间的关系,获得自热导系数和互热导系数,构建出直埋电缆群缆芯温升快速计算的转移矩阵 ...
傅晨钊, 郝谦, 梁永春, 司文荣
doaj
Shuitu baochi tongbao, 2022 [Objective] The response law for runoff under different land use scenarios in the middle and upper reaches of the Weihe River was analyzed in order to provide scientific support for development planning and water resource management of the middle and ...
Zhang Ye +9 more
doaj +1 more source
Efficient algorithm for computing Walsh spectrum and differential probability [PDF]
, 2015 According to the characteristic of T-functions,along with the definition of narrow T-functions,the linear prop-erty and differential property were studied.Markov chain and transition matrices were constructed to propose fast algo-rithm for computing ...
IUYan L, UBin H, ULi-ping X
core +1 more source
Temporal and Spatial Changes of Land Use and Their Eco-environmental Effects in Nanchang City from 2000 to 2020 [PDF]
, 2022 [Objective] The regional ecological environmental effects caused by land use changes in Nanchang City by determining the quantitative relationships between regional land and resource development and ecological environments were analyzed in order to ...
Tang Jianglong +2 more
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Spatial-temporal Evolution and Prediction of Ecosystem Carbon Storage on Hainan Island by Coupling InVEST and FLUS Models [PDF]
, 2023 [Objective] The influence of land use changes on carbon storage were studied under the expansion of urbanization in Hainan Island to reveal the spatial-temporal evolution pattern of carbon storage and to predict future development trends in order to ...
Chen Xu +5 more
core +1 more source
Improvement of the Hopfield Neural Network and Transfer-matrix calculation of positional distribution in the 2-dimensional semiflexible polymer [PDF]
, 2006 摘要本文主要分为两个部分，第一部分为用蒙特卡罗变异优化选择规则优化Hopfield神经网络，第二部分为转移矩阵在二维半柔软聚合物研究中的应用。第一部分研究表明蒙特卡罗变异优化选择规则可以用来优化神经网络的性能。在第一部分我们以Hopfield网络为例，运用蒙特卡罗变异优化选择规则在保持网络的整体结构基本不变的情况下，优化Hopfield神经网络的动力学特性，提高网络的存储功能和存储质量。在优化后的网络中，每个记忆模式都被严格设计成网络的不动点吸引子，从而每个模式都能够被精确联想 ...
周震
core +1 more source
Shuitu Baochi Xuebao, 2022 利用贵州省1980-2020年逐月降水与土壤水分计算标准化降水指数(SPI)和标准化土壤水分指数(SSI),基于游程理论、传播响应率(Rr)、状态转移概率矩阵等方法探究气象与农业干旱特征变化,以及两者之间的响应关系。结果表明:(1)贵州省农业干旱较气象干旱持续时间长、烈度大,干旱历时空间变化较气象干旱显著,干旱烈度则较单一。(2)季尺度上,春季农业干旱对气象干旱响应最为敏感,夏、秋季次之,冬季较弱;不同地貌类型下,春、冬季在半喀斯特低中山响应程度较高,夏季在峰丛谷地,秋季在非喀斯特地区;不同切割深度下 ...
游漫 +4 more
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Shuitu Baochi Xuebao, 2023 识别三生空间迁移演化规律并掌握其引发的空间性状改变情况,对优化国土空间布局、提高利用水平影响深远。以黄河流域上游城市群为研究对象,基于转移矩阵对研究区2000—2020年三生空间时空演化规律进行分析,并以此为基础,利用强度分析模型,从三生空间一、二级分类双重视角,就空间演化带来的变化稳定性问题进行讨论。结果表明:(1)20年间,研究区三生空间转移变化活跃但发生数量和规模均呈缩减态势,空间转移以呼包鄂榆和宁夏沿黄城市群两地为主,呈东多西少分布特征,但以生态为主、生产和生活空间为辅的整体格局未发生改变。(2)
黄鑫 +5 more
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Multiview Spectral Clustering Based on Weighted Tensor Low-Rank Constraint [PDF]
Many existing multiview clustering methods fail to simultaneously exploit the high-order correlations embedded in different views and the global geometric structure of each single view, resulting in inadequate clustering performance.
Sihui LIU, Quanxue GAO, Wei SONG, Deyan XIE
core +1 more source
Spatiotemporal Coupling Relationship Between Plateau Pika Disturbance and Alpine Meadow Degradation [PDF]
, 2023 [Objective] Plateau pika (Ochotona curzoniae) is a key species in the alpine meadow ecosystem of the Qinghai-Xizang Plateau. The coupling relationship between pika activity and meadow degradation was analyzed in order to further improve the observation ...
Gao Chongyue +5 more
core +1 more source