Results 21 to 30 of about 12,320 (118)
四川大学学报. 自然科学版, 1978 两个相互等价的型有相同的行列式,且对变元的所有整数值来说,它们所表之数相同。反之,表数相同的两个型却不一定等价。M.Bauer曾证明行列式相同,表数相同的两个真本原整系数恒正二次型必等价。曾用几何方法证明只有一对表数相同,互不等价的二元恒正型:a（x2+3y2）和a（x2+xy+y2）。后来,给出了一系列表数相同而行列式不同的三元恒正型。本文将对表数相同、行列式亦相同但互不等价的n元型（n≥3）进行探讨,并给出所得结果以一个直接的证明。
柯召, 郑德勋
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International Journal of Urban and Regional Research, Volume 50, Issue 1, Page 191-220, January 2026.Abstract Henry George advocated for capturing land value increases for public ends. The active approach of public authorities organizing and financing land development can help capture higher land value increases, as Hartman and Spit indicate. However, this approach hardly happens in developing countries, where the coalition of private developers and ...
Nannan Xu
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Zhejiang Daxue xuebao. Lixue ban, 2017 通过引入参数σ和应用权函数的方法，建立了一个具有最佳常数因子的非单调且非齐次核的Hilbert型积分不等式及其等价形式，并考虑了特殊结果.
ZHONGJianhua(钟建华) +2 more
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A risk-measure and premium pricing model(一种风险度量与保费定价模式)
Zhejiang Daxue xuebao. Lixue ban, 2004 在“修正确定等价” (modified certainty equivalent)风险度量模式的基础上，引入风险度量安全系数λ，建立了 一种适用范围吏广的组合风險的度量模式——安全修正风险度量，从而也得到一种组合风险的保费定价模式. 由此，达到了风险的度量和保费定价的有机结合，同时，也将经典的“平均值原理”从个体风险推广到了组合投资和组合风险的度量定价中.
SHENYin-fang(沈银芳)
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New Directions for Child and Adolescent Development, Volume 2026, Issue 1, 2026.Background Working memory updating is crucial in bilingual children′s second language (L2) reading comprehension. A robust updating ability is a cognitive key for children to successfully master L2 reading comprehension. Objective This study is aimed at investigating the effect of updating ability on the L2 Chinese reading comprehension among Uyghur ...
Guangxin Li +3 more
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四川大学学报. 自然科学版, 2009 作者从经济均衡理论出发,考虑了区间[0,T]上基于供应链的动态网络均衡模型,导出了与空间价格均衡条件等价的变分不等式,并给出该变分不等式解的存在唯一性结果。
袁春强 +3 more
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Zhongguo shiyan zhenduanxue, 2023 我国高等教育学生能力评价方法，主要采取的是专业知识能力的客观化测量，如高等学校招生统一考试、学位英语考试、课程期末终结性考试等。此类考试能够对学生专业水平特别是专业知识掌握情况进行较为准确的判断，评价往往是针对某一学科或某几个学科的，但此类能力评价维度有限，难以多维度评估学生的综合素质和能力。而班主任和班组对高等教育毕业生能力的鉴定，往往因师生比例失调，导致评价结果模板化且多流于形式。成人高等学历教育是终身教育体系和继续教育体系的重要组成部分，是我国高等教育的一种重要形式[1]。
蒙世佼 +5 more
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Integrative Conservation, Volume 4, Issue 4, Page 665-674, December 2025.Using a diagnostic mitochondrial marker gene, we document the presence of furry‐eared dwarf lemurs, a species known from Madagascar's eastern montane rainforests, in several forest fragments across the island's central highlands. These findings raise new questions about when this species colonized these sites, how they tolerate these changing and ...
Marina B. Blanco +27 more
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A half-discrete Hilbert-type inequality with a non-homogeneous kernel(一个半离散非齐次核的Hilbert型不等式)
Zhejiang Daxue xuebao. Lixue ban, 2017 引入独立参数，应用权函数的方法及实分析技巧，建立一个具有最佳常数因子的半离散非齐次核的Hilbert型不等式，还考虑了其具有最佳常数因子的等价形式.
YANGBicheng(杨必成) +1 more
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People and Nature, Volume 7, Issue 11, Page 2700-2713, November 2025.Abstract Large old trees are important ecological entities in human settlements, providing cultural values and ecological services that are threatened by current and future changes in global climate, land use and disturbance regimes. Some studies suggest incorporating social and cultural significance into the conservation of large old trees.
Zhuo Cheng +5 more
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