Results 81 to 90 of about 1,217,548 (163)
关于丢番都方程（a2-b2）x+（2ab）v=（a2+b2）2
四川大学学报. 自然科学版, 1959 除x=y=z=2外,有无其他正整数解。Jesmanowicz的猜测是没有其他正整数解。并且证明了对于b,a=2,3;3,4;4,5;5,6,他的猜测是成立的。作者曾对a=n+1,b=n,其中n为自然数时得出了一些结果 ...
柯召
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Assessing and strengthening community‐based coastal governance
Conservation Biology, Volume 40, Issue 5, October 2026.Abstract Community‐based coastal governance is essential for biodiversity conservation and sustainable livelihoods, yet many communities continue to face significant challenges in establishing and sustaining effective governance systems. We sought to improve understanding of the current status of community‐based coastal governance across five countries
Mark Andrachuk +21 more
wiley +1 more source
Power Leveraging: The Everyday Expansion of the Grassroots State in Urban China
Law &Policy, Volume 48, Issue 4, October 2026.ABSTRACT China has witnessed a notable expansion of state power during and after the pandemic, particularly at the grassroots level. How has this occurred? The Shequ, a grassroots state agent, has played a central role, taking on extensive administrative responsibilities aimed at enhancing social management, often at the expense of rule‐of‐law ...
Aokai Yang
wiley +1 more source
四川大学学报. 自然科学版, 2008 利用积分方程,作者通过构造适当的Banach空间考察了一类含有一阶导数的二阶三点边值问题的解和正解的存在性.利用Leray-Schauder不动点定理,作者证明了只要非线性项在其定义域的某个有界子集上的"高度"是适当的则该类问题可以有一个解或者正解.
姚庆六
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Predictive evolutionary genomics: principles, validation, and practice
New Phytologist, Volume 252, Issue 1, Page 36-48, October 2026.Summary Climate change and habitat loss are driving rapid evolutionary responses in populations world‐wide, which creates an urgent need for evolutionary forecasting in conservation and agriculture. Such forecasting can be categorized into three time scales: trait‐based models that use multivariate quantitative genetic equations to project correlated ...
Daniel Ortiz‐Barrientos +5 more
wiley +1 more source
Fisher-Kolmogorov-Petrovskii-Piskunov方程的定态分歧
四川大学学报. 自然科学版, 2013 运用规范化的Lyapunov-Schmidt约化方法,在Direchlet边界条件下证明了Fisher-Kolmogorov-Petrovskii-Piskunov方程产生分歧,得到了分歧解的具体表达式和分歧解的正则性;在Neumann边界条件下得到了该方程产生超临界分歧和次临界分歧的完整判据、分歧解的具体表达式以及分歧解的正则性.
张强, 雷开洪, 向丽
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Green Hydrogen in Brazilian Media: Dominant Narratives and Missing Dimensions of the Energy Trilemma
Politics &Policy, Volume 54, Issue 5, October 2026.ABSTRACT Media discourses help shape the visibility and legitimacy of energy transition pathways in the public sphere. This study examines how Brazilian mainstream newspapers framed green hydrogen and assesses the alignment of these narratives with the energy trilemma: energy security, environmental sustainability, and social accessibility. We analyzed
Flávia Mendes de Almeida Collaço +3 more
wiley +1 more source
四川大学学报. 自然科学版, 2003 作者为解决NaI(Tl)γ谱仪在测量过程中谱漂移对解谱的影响,提出了一种软件分时动态谱漂移修正方法,并用3组份点源进行了检验.结果表明,修正后用神经网络方法解谱的误差由4.6%减少到3.0%.
谢奇林 +5 more
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一个Fisher型反应扩散方程解的全局Threshold现象
四川大学学报. 自然科学版, 1990 在反应扩散方程的研究中,解的渐近性态占有重要地位,其中关于平衡解稳定性的研究有不少的工作.在这些研究中,就Neumann齐次边、初值问题说来,一般都假设方程仅有一个正常数平衡解,如文[3—7]、[11,12].
陆征一
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