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951.
黄云姬 《贵阳师范高等专科学校学报》2012,(3):45-47
屈原以其杰出的文学成就和高洁的人格,成为后代文人士大夫学习的典范。辛弃疾用自己的方式继承和发展着屈原精神及其创作上的艺术手法,屈原及其骚赋已深入到辛词内部,成为辛词不可缺少的重要部分。这一切都源于辛弃疾对屈原更深层意义上的相承关系,即辛弃疾身上浓厚的屈原情结:两人都有着执迷求索的悲剧人生,有着功名与诗名之间的理想困惑,都有依附与独立的矛盾人格。 相似文献
952.
企业竞争关系演变的复杂网络分析——以广东省软件产业为例 总被引:9,自引:0,他引:9
首先根据2002~2006年每年度广东省软件产业内企业及产品的数据,分年度构建了企业竞争关系复杂网络模型;然后用各种静态几何量分析了每年度网络的结构属性,比较了不同静态几何量之间的关系,并探讨了网络增长的动力机制和经济学背景。通过分析发现,每年度网络的顶点度都服从幂律尾部分布;同时,网络具有小世界特性,并有增长性和偏好性,从而得出这些网络都近似于无标度网络和小世界网络的结论。最后,本文还讨论了软件企业竞争关系复杂网络分析在宏观、微观和动态演变方面的产业组织学意义和启示。 相似文献
953.
954.
通过引进三维复函数的概念和其性质,推广了二维解析函数,将空间理想流体问题求解归结为该函数的边值问题.从而为解决该类问题提供了一种新的方法. 相似文献
955.
Solid state reactions between β-diketones (HPMBP, HDBM) and LnAc3 · xH2O(La,Nd:x=3/2; Tb:x=4) have been investigated at low heating temperature. Pure compounds of Ln(PMBP)3 and Ln(DBM)3 are obtained by solid state reaction, and characterized by elemental analysis, infrared radiation (IR), X-ray diffraction
(XRD) and photoacoustic spectra. The solid state reaction properties of β-diketones and their influences on the structures
of products are discussed.
Project supported by the National Natural Science Foundation of China (29475209) 相似文献
956.
Physical properties of a crystal are related to its constituent chemical bonds,which show the interaction of all constituent atoms. Chemical bonding behaviors and bond parameters of a crystal are the important indices that can reasonably express this kind of interaction. Therefore, studying constituent chemical bonds of a crystal is a fundamental method to understand its structure-property relationships, it also would be potentially applicable to the predictions of properties of new crystals and the designing of new type of functional crystal materials. In my doctoral dissertation, starting from the constituent chemical bonds of crystals and using the structure-nonlinear optical (NLO) property relationship as a useful guide, the author carried out basic researches toward the goal of materials designing i.e.crystal engineering. 相似文献
957.
Goals and plans organize much of complex problem solving behavior and are often inferable from action sequences. This paper addresses the strengths and limitations of inferring goals and plans from information that can be derived from computer traces of software used to solve mathematics problems. We examined mathematics problem solving activity about distance, rate, time relationships in a computer software environment designed to support understanding of functional relationships among these variables (e.g., distance =rate × time; time=distance/rate) using graphical representations of the results of simulations. Ten adolescent-aged students used the software to solve two distance, rate, time problems, and provided think-aloud protocols. To determine the inferability of understanding from the action traces, coders analyzed students' understanding from the computer traces alone (Trace-only raters) and compared these to analyses based on the traces plus the verbal protocols (Traceplus raters). Inferability of understanding from the action traces was related to level of student understanding how they used the graphing tool. When students had a good understanding of distance, rate, time relationships, it could be accurately inferred from the computer traces if they used the simulation tool in conjunction with the graphing tool. When students had a weak understanding, the verbal protocols were necessary to make accurate inferences about what was and was not understood. The computer trace also failed to capture dynamic exploration of the visual environment so students who relied on the graphing tool were inaccurately characterized by the Trace-only coders. Discussion concerns types of scaffolds that would be helpful learning environment for complex problems, the kind of information that is needed to adequately track student understanding in this content domain, and instructional models for integrating learning environments like these into classrooms.Members of the Cognition and Technology Group at Vanderbilt who have contributed to this project are (in alphabetical order) Helen Bateman, John Bransford, Thaddeus Crews, Allison Moore, Mitchell Nathan, and Stephen Owens. The research was supported, in part, by grants from the National Science Foundation (NSF-MDR-9252990) but no official endorsement of the ideas expressed herein should be inferred. 相似文献
958.
我国U-23岁足球队技战术训练课质量综合评价的研究 总被引:4,自引:1,他引:3
通过对我国26支U—23队伍的技战术训练课进行研究,建立了一套能够综合评价我国优秀青年足球队技战术训练课质量的评价指标、标准和方法 相似文献
959.
介绍生态绿地系统在维持城市生态平衡、提高城市居民生活环境质量方面的主要功能,并提出一个合理的城市生态绿地系统规划的基本方法。 相似文献
960.
利润指标是衡量企业获利能力的一个基本指标,也是度量企业财富增量的一个主要指标.因此利润质量的高低关系到对企业经营评价的正确与否,本文从利润质量研究的必要性入手,着重阐述了利润质量的影响因素,提出了判断利润质量高低的标准. 相似文献