Results 11 to 20 of about 21,006 (128)
智能科学与技术学报, 2021 经典的稀疏表示分类（SRC）通常是基于求解L1最小化问题的。SRC在原始输入空间中求解L0范数最小化问题，无法很好地获取数据中的非线性信息。为了解决这一问题，应用非线性映射将原始输入数据映射到一个新的高维特征空间，并提出了一种新的基于L0范数的表示方法。在所提方法中，表示测试样本的字典包含两个部分：第一部分固定在测试样本的近邻；第二部分的训练样本通过半遗传算法（SGA）来选择，利用表示误差确定第二部分的表示字典。在所提方法中，如果训练样本和已确定的测试样本的近邻产生最小表示误差，那么这些训练样本将被 ...
石林瑞 +4 more
doaj
A boundary-type meshless method for the Robin inverse problem(一种求解Robin反问题的边界型无网格方法)
Zhejiang Daxue xuebao. Lixue ban, 2013 给出一种求解非齐次稳态热传导方程Robin反问题的边界型无网格方法.该方法首先利用Newton法则将Robin反问题转化为Cauchy问题，然后用边界粒子法处理非齐次项以避免区域内部的离散节点，并结合基本解方法分别求得近似特解以及相应齐次问题的近似解.鉴于所考虑问题的不适定性，引入截断奇异值分解和L-曲线准则来求解离散后得到的高度病态的线性方程组.最后给出数值例子说明该方法的稳定性和有效性.
DONGChao-feng(董超峰)
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Gaoya dianqi, 1979 本文全面地介绍了以行波法为基础对电力系统中的操作过电压求数值解的一种方法、即Bergeron方法。主要内容有:本法的一些理论基础;矩阵代数与模分析理论;线路参数的计算公式、参数的频率特性;富氏变换技术(MFT;FFT算法等);非线性元件(电抗器、避雷器、变压器等)的数学模型及迭代解法,操作过电压(重合闸、合闸过电压)的一个完整的算例等等。初步估计,分为6～7章。
王秉钧
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, 2011 在对称区域中,构造出满足对称边界条件的基本解函数,并推广到基本解方法(MFS)中求解Poisson方程的边界值问题.利用构造出的基本解,输入数据和所需求解的线性方程组数目可减少到原来(不利用对称性的基本解函数所需的方程组数目)的1/2或1/4,具有计算时间短、精度高、编程简单、输入数据少等优点.通过数值计算可以看出,计算结果与解析解之间的误差很小 ...
丁华建 +4 more
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Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Root exudates play a key role as signals and nutrients in mediating plant–microbe communication. However, critical knowledge gaps remain regarding how root exudates mediate soil–microbe–plant interactions to regulate crop yield under long‐term straw mulching combined ...
Jiajie Song +7 more
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Methods in Ecology and Evolution, EarlyView.Abstract Molecular identification of insect food webs can accurately reveal complex trophic interactions and serve as a foundation for understanding ecosystem functioning and advancing biodiversity conservation. This process typically involves DNA library construction, high‐throughput sequencing and subsequent steps, including data assembly, annotation,
Xiao‐man Zhang +9 more
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Comprehensive framework for assessing and optimizing existing research networks
Conservation Biology, EarlyView.Abstract Conservation, monitoring, and research networks, or collections of ecological research sites unified under a common mission of data collection or a research mission, are essential infrastructure for understanding large landscapes. However, most networks developed opportunistically over decades rather than through systematic design, creating ...
Alyson East +2 more
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A filled function algorithm for unconstrained global optimization problems(一个求解无约束优化问题的填充函数算法)
Zhejiang Daxue xuebao. Lixue ban, 2011 填充函数法是求解无约束全局优化问题的一种方法，这种方法的关键是构造具有良好性质的填充函数.基于填充函数定义与性质的基本要求，构造了一个新的求解无约束全局优化问题的单参数填充函数.该函数形式简单，便于计算，并建立了相应的填充函数算法.最后，进行了数值试验，结果表明，该算法是有效的.
HESu-xiang(贺素香) +1 more
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Representation of obligate groundwater‐dwelling copepod diversity in European protected areas
Conservation Biology, EarlyView.Abstract Groundwaters sustain diverse surface ecosystems and are populated by metazoan species, mostly invertebrates, that provide fundamental ecological functions and are often of prominent conservation value due to narrow endemism and high phylogenetic rarity.
Francesco Cerasoli +7 more
wiley +1 more source
Conservation Biology, EarlyView.Abstract In the western United States, conservation practitioners are increasingly working with private landowners to restore habitat for North American beavers (Castor canadensis) and to use nonlethal mitigation techniques when beavers damage crops and infrastructure.
Brian D. Erickson, Megan S. Jones
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