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101.
102.
肖向平 《广西右江民族师专学报》2008,(2):52-56
党的十七大报告首次将邓小平理论、“三个代表”重要思想以及科学发展观等重大战略思想概括为“中国特色社会主义理论体系”,这一科学概括,从时间维度界定该体系是对改革开放历史新时期中国共产党理论创新成果的科学总结,从内容维度充分展现了该体系是马克思主义中国化最新成果,从特征维度彰显了该体系是不断发展开放的理论体系。这一科学理论体系为我们夺取全面建设小康社会新胜利提供了强大的思想保证,从这三个维度认真学习深刻领会它,对于坚持和发展中国特色社会主义事业具有深远的实践意义。 相似文献
103.
Andreas Grenner Georgios M. KontogeorgisNicolas von Solms Michael L. Michelsen 《Fluid Phase Equilibria》2007
The simplified PC-SAFT equation of state has been applied to liquid–liquid, vapor–liquid and solid–liquid equilibria for mixtures containing 1- or 2-alkanols with alkanes, aromatic hydrocarbons, CO2 and water. For the alkanols we use generalized pure compound parameters. This means that two of the physical pure compound parameters, m (segment number) and σ (segment diameter), are obtained from linear extrapolations, since m and mσ3, increase linearly with respect to the molar mass, and moreover, the two association parameters (association energy and association volume) were assumed to be constant for all alkanols. Only the dispersion energy is fitted to experimental data. Thus it is possible to estimate parameters for several 1- and 2-alkanols. The final aim is to develop a group contribution approach for PC-SAFT which is suitable for complex compounds, considering that the motivation of this project is to obtain a thermodynamic model which can be used in the development of sophisticated products such as pharmaceuticals, polymers, detergents or food ingredients. One of the severe limitations in applying SAFT-type equations of state to these compounds is that the procedure for obtaining the pure compound parameters is usually based on fitting to saturated vapor pressure and liquid density data over an extended temperature range. However, such data are rarely available for complex compounds. To verify the new pure compound parameters, comparisons to ordinary optimized alkanol parameters, where all five pure compound parameters were fitted to experimental liquid density and vapor pressure data, were made. The results show that the new generalized alkanol parameters from this work perform at least as well as other alkanol parameter sets. 相似文献
104.
We discuss relations among notions of (C,1)-convergence, almost-convergence, absolute almost-convergence, and View the MathML source" title="View the MathML source" src="http://ars.els-cdn.com/content/image/1-s2.0-S0022247X07000157-si2.gif">-convergence of a continuous vector-valued function f(t) as t tends to infinity. Equivalent conditions and Tauberian criterions are obtained, and some examples are exhibited. 相似文献
105.
Predrag S. Stanimirovi? Dragana S. Cvetkovi?-Ili? Sladjana Miljkovi? Marko Miladinovi? 《Applied mathematics and computation》2011,217(22):9358-9367
We present the full-rank representations of {2, 4} and {2, 3}-inverses (with given rank as well as with prescribed range and null space) as particular cases of the full-rank representation of outer inverses. As a consequence, two applications of the successive matrix squaring (SMS) algorithm from [P.S. Stanimirovi?, D.S. Cvetkovi?-Ili?, Successive matrix squaring algorithm for computing outer inverses, Appl. Math. Comput. 203 (2008) 19-29] are defined using the full-rank representations of {2, 4} and {2, 3}-inverses. The first application is used to approximate {2, 4}-inverses. The second application, after appropriate modifications of the SMS iterative procedure, computes {2, 3}-inverses of a given matrix. Presented numerical examples clarify the purpose of the introduced methods. 相似文献
106.
107.
In this brief letter, we modify the classic social force model of Helbing which is applied to simulate how a pedestrian gets outside a hall full of smoke. As the Vicsek model does, the view radius is introduced to describe the range the pedestrian can see. The relation between the evacuation time and the view radius is studied with different numbers of pedestrians. The results show that the shorter the view radius is, the more time walkers will spend escaping, and even fail to escape. And the relation between the number of remaining walkers and the view radius shows non-monotonicity, if the number of pedestrians is larger than 600. And lastly, we propose to enlarge the width of the exit or to add two small exits in the corners, which may decrease the evacuation time greatly and obviously reduce the number of remaining walkers. 相似文献
109.
The temporal power-law decay is one class of interesting decay processes, usually indicating a long-time correlation and benefiting for a system to perform functions in various time-scales. In this work, I collect the data of the view times versus lectures of some scientific courses on YouTube, according to some special principles. These data can reflect the dynamical property of the spontaneous learning behavior, influenced by the decay of learning interest. The view times versus lectures show an obviously power-law decay process. The power approximates to 1, a universal constant. This finding brings the learning process into the interesting power-law family. It will be of interest in the fields of the human dynamics, psychology and education. 相似文献
110.