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, 1997 本研究通过对被试求解换位棋过程的记录与分析，重点研究了问题表征在换位棋求解过程中的作用。实验结果表明：（1）正确表征问题规则是解题的必要前提.对问题规则信息的误解和遗漏，是影响解题正确率的重要因素。其中对非隐含问题规则的错误表征也占全部错误表征的很大比率。（2）“关键结构”的发现是解决换位棋的必要条件，对问题规则的错误表征影响“关键结构”的发现.（3 ...
王东晖, 傅小兰
core +1 more source
关于方程sum from j=0 to h（x+j）n=（x+h+1）n
四川大学学报. 自然科学版, 1978 我们曾证明6≤n≤33时,（1）无正整数解,以及其他若干结果。P.Erd?o对于x=1的情形,曾猜测（1）除开1+2=3外,无其他正整数解,L.Moser证明了这个猜测在h+2≤1010～6时成立。本文将证明:方程（1）在n是奇数时,除开已知的n=3,h=2,x=3和n=h=x=1外无其他正整数解,这个证明初等而简短。运用这个方法还可证明在2β|n,h（?）1,2(mod2β+3),β>0或n=2s,3·2s,s>1时,（1）均无正整数解。
柯召, 孙琦, 邹兆南
doaj
AI foundation models in plant biology
New Phytologist, EarlyView.Foundation models decode genomes, engineer proteins, phenotype crops, and drive AI agents across plant biology. This figure was created in BioRender (BioRender.com/xcmmkel). Summary Rapid technological progress has enabled plant biologists to accumulate unprecedented volumes of multi‐scale, multi‐modal data, yet this abundance of data has intensified ...
Haopeng Yu
wiley +1 more source
There Is Always a Bigger Fish. Determinants of Power Perceptions in Swiss Biodiversity Policy
Policy Studies Journal, EarlyView.ABSTRACT The Advocacy Coalition Framework (ACF) views power as crucial in policy processes, but the nature of coalition power, its determinants, and how to empirically measure it remain understudied. In this article, we use a mixed method approach and social network analysis to explore power relationships in the biodiversity policy subsystem in ...
Alix d'Agostino +2 more
wiley +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2013 采用不同链长的有机硅烷作为表面修饰剂，在正庚烷/正丁醇中利用溶剂热合成法制备得到亲油性纳米ZSM-5分子筛.通过有机硅烷与氧化物晶种表面的羟基作用，其长链化学键合到晶种表面，形成保护层，既抑制了氧化物颗粒间的团聚，又控制了纳米ZSM-5的粒径.所制备的纳米ZSM-5平均粒径为20~70 nm，且粒径随着有机硅烷碳链长度的降低而逐渐减小.添加一定量的该纳米ZSM-5到碳氢燃料模型化合物正十二烷中，在管式反应器中（550 ℃，4 MPa）考察催化裂解行为，结果表明该亲油性纳米ZSM ...
LIUJia-zhen(刘家珍) +4 more
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Resource Substitution: Local Governments' Issue Attention and Policy Reinvention
Policy Studies Journal, EarlyView.ABSTRACT Research on policy reinvention, where a government modifies rather than replicates policy innovations introduced by other governments, has progressed significantly, but how it is influenced by the government's issue attention has not been thoroughly examined.
Yingxin Zhang, Yixue Yao, Kaifeng Yang
wiley +1 more source
四川大学学报. 自然科学版, 1985 本文应用Leray—Schauder度理论讨论了Hammerstein方程连续正解的存在性和个数.本文结果是[1]中某些结果的改进和推广.
严家鹤, 张庆雍
doaj
Zhejiang Daxue xuebao. Lixue ban, 2008 考察了非线性四阶三点边值问题的正解.通过构造适当的锥并且利用相应的积分方程证明了n个正解的存在性.主要工具是锥上的Krasnosel'skii不动点定理.
YAOQing-liu(姚庆六)
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