Results 11 to 20 of about 23,991 (132)
Zhejiang Daxue xuebao. Lixue ban, 2023 研究了二阶非齐次边值问题-u''(t)+k2ut=f(ut), t∈[0,1],u'(0)=0, u'(1)=b正解的存在性与多解性，其中k,b>0为常数， f∈C[0,∞),[0,∞)， f0 :=limu→0+ f(u)u=0 , f∞ :=limu→∞ f(u)u=∞。 运用上下解方法和拓扑度理论，证明了存在常数 b*>0，使得当 ...
石轩荣(SHI Xuanrong)
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Zhejiang Daxue xuebao. Lixue ban, 2023 研究一类非齐次项是p-Laplace算子的椭圆方程组非常弱解的正则性。结合Hodge分解以及偏微分方程正则性理论的证明技巧，建立了具有p-Laplace型椭圆方程组的非常弱解与经典意义下的弱解之间的关系。
陈淑红(CHEN Shuhong)
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Discussion on the Diophantine equation X2-(a2+1)Y4=35-12a(关于丢番图方程X2-(a2+1)Y4=35-12a的讨论)
Zhejiang Daxue xuebao. Lixue ban, 2016 设a是正整数，证明了当a=1时，方程X2-(a2+1)Y4=35-12a仅有正整数解（X，Y）= (5，1)；当α=2 时，该方程仅有正整数解(X，Y)=(4，1)和(56，5)；当a=3时，该方程仅有正整数解(X，Y)=(3，1)；当a=4时，该方程仅有正整数解（X，Y）= (2，1)和(202，7)；当a=5时，该方程仅有1组互素的正整数解(X，Y) = (1，1)；当a=6 时，该方程无正整数解(X，Y)；当a≥7且12a+1为非平方数时，该方程最多有3组互素的正整数解(X，Y)；当a≥7且12a+
GUANXungui(管训贵)
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On positive definite solution of a class of nonlinear matrix equations(一类非线性矩阵方程的正定解)
Zhejiang Daxue xuebao. Lixue ban, 2019 讨论非线性矩阵方程的Hermite 正定解及其扰动问题。提出了该方程存在唯一正定解的充分条件，给出了迭代解法。讨论了唯一正定解的扰动问题，给出了上界估计，得到了唯一正定解的Rice 条件数的显式表达式，并用数值例子对所得结果进行了验证。
FANGLiang(房亮), LIUSanyang(刘三阳)
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Zhejiang Daxue xuebao. Lixue ban, 2023 研究了一类一阶半正周期边值问题u'(t)=λa（t）[f（u（t））-k], t∈[0,1],u(0)=u(1)正解的存在性，其中，k>0为常数，λ>0为参数。权函数a：[0，1]→R为连续函数，f或是定义在[0，∞)上的非负连续函数，满足 f(0)=0且在无穷远处是次线性的，或是定义在(0，∞)上的正连续函数且在0处具有奇异性。运用上下解方法证明了该问题正解的存在性。
杨伟(YANG Wei)
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Zhejiang Daxue xuebao. Lixue ban, 2006 将用于求解椭圆型偏微分方程边值问题的基本解方法应用于求解一个三维线弹性反问题，即Navier方程组的Cauchy问题.基本解方法离散方程所得的线性方程组是高度病态的，常见的求解方法如最小二乘法等无法得到合理的解.文中应用Tikhonov正则化和截断奇异值分解这两种正则化方法求解线性方程组，所需正则化参数则根据L-曲线确定，克服了问题的病态性.数值算例表明，本文方法能有效地求解三维线弹性力学反问题，而且这两种正则化方法所得到的结果精度相当.
WANGJun(王钧) +2 more
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Zhejiang Daxue xuebao. Lixue ban, 2016 讨论了一类带有Crowley-Martin和比率依赖反应函数的扩散捕食-食饵模型.首先利用局部分歧理论考察了系统关于强半平凡解处产生正解的存在性，再运用扰动理论得到了正解的稳定性.最后借助全局分歧理论和不动点指数理论给出了正解多重性的条件.
LIHaixia(李海侠)
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European Policy Analysis, EarlyView.ABSTRACT Policy process research has excelled in explaining structural policy change within national settings, but extensions and applications to the EU level have long proven challenging for scholars. Given that the EU is currently experiencing its longest period of Treaty stability since the 1980s—having evolved into a sui generis political system ...
Vassilis Karokis‐Mavrikos
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Equine Veterinary Journal, EarlyView.Abstract Background The middle conchal sinus (MCS) (ethmoidal sinus) remains one of the least understood equine paranasal compartments. Despite recognition of its involvement in sinonasal disease, disorders of the MCS often remain underdiagnosed in the absence of computed tomographic (CT) imaging due to limited anatomical understanding and challenges ...
J.‐B. Pavard +3 more
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Beyond Universalism: A Contextual Approach to Comparative Public Administration
Public Administration and Development, EarlyView.ABSTRACT In this essay, I advocate for a contextual approach to comparative public administration, arguing that effective governance reform requires moving away from universal models to embrace local political, socioeconomic, and institutional realities.
XiaoHu Wang
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