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101.
分子间的范德华力是十分微弱的,但可以说普遍的存在着,在很多体系中起着巨大的作用,在物理学、化学、生物学等学科中得到了广泛的研究。但怎样计算范德华力?如何考虑各种条件对范德华力的影响?  相似文献   
102.
在国内外综合因素的影响下,我国主流意识形态的指导地位存在安全隐患,因此加强意识形态工作,确保意识形态安全是摆在我们面前的一项重大而艰巨的任务。  相似文献   
103.
The consistency measurement and weight estimation approach of the hybrid uncertain comparison matrix in the analytic hierarchy process (AHP) are studied. First, the decision-making satisfaction membership function is defined based on the decision making's allowable error. Then, the weight model based on the maximal satisfactory consistency idea is suggested, and the consistency index is put forward. Moreover, the weight distributing value model is developed to solve the decision making misleading problem since the multioptimization solutions in the former model. Finally, the weights are ranked based on the possibility degree approach to obtain the ultimate order.  相似文献   
104.
μC/OS-Ⅱ is an open source real-time kernel adopting priority preemptive schedule strategy. Aiming at the problem of μC/OS-Ⅱ failing to support homology priority tasks scheduling, an approach for solution is proposed. The basic idea is adding round-robin scheduling strategy in its original scheduler in order to schedule homology priority tasks through time slice roundrobin. Implementation approach is given in detail. Firstly, the Task Control Block (TCB) is extended. And then, a new priority index table is created, in which each index pointer points to a set of homology priority tasks. Eventually, on the basis of reconstructing μC/OS-Ⅱ real-time kernel, task scheduling module is rewritten. Otherwise, schedulability of homology task supported by modified kernel had been analyzed, and deadline formula of created homology tasks is given. By theoretical analysis and experiment verification, the modified kernel can support homology priority tasks scheduling, meanwhile, it also remains preemptive property of original μC/OS-Ⅱ.  相似文献   
105.
High-density event-related potentials (ERPs) were measured when participants were required to evaluate oneself, significant others (father and mother) and the most familiar public figures (Lei Feng and Jiang Qing) based on trait adjectives. There were three referential conditions and a non-referential control condition including self-evaluation (SE), significant other-evaluation (SOE), general other-evaluation (GOE), and semantic positivity-evaluation (SPE). The behavioral data showed that RTs to GOE condition were longer than the other three conditions. Scalp ERP analysis revealed that (1) SPE condition elicited a more negative N2 than SE condition, which was associated with inhibition of responses; (2) SE condition elicited a more positive P300 than SPE condition, which was an index of attention to self-relevant stimuli; (3) there was no difference on the amplitude and latency of P300 between SE and SOE conditions, which reflected that the concept of “self” included intimate others (e.g., father and mother) in Chinese culture.  相似文献   
106.
Zebrafish miR-214 modulates Hedgehog signaling to specify muscle cell fate   总被引:3,自引:0,他引:3  
Numerous microRNAs (miRNAs) have been discovered in the genomes of higher eukaryotes, and functional studies indicate that they are important during development. However, little is known concerning the function of individual miRNAs. We approached this problem in zebrafish by combining identification of miRNA expression, functional analyses and experimental validation of potential targets. We show that miR-214 is expressed during early segmentation stages in somites and that varying its expression alters the expression of genes regulated by Hedgehog signaling. Inhibition of miR-214 results in a reduction or loss of slow-muscle cell types. We show that su(fu) mRNA, encoding a negative regulator of Hedgehog signaling, is targeted by miR-214. Through regulation of su(fu), miR-214 enables precise specification of muscle cell types by sharpening cellular responses to Hedgehog.  相似文献   
107.
李帆  赵建辉 《系统仿真学报》2008,20(5):1214-1217,1237
智能化是当今世界的发展趋势。智能材料结构作为研究热点之一,应用于航空、航天、生物及医药等诸多领域。智能作动器与智能传感器是智能材料结构的两个主要研究方向。迟滞现象是存在于大量智能材料中的非线性现象,对整个控制系统可能带来不良影响,如稳定性的恶化甚至丧失等。Preisach模型常用于智能材料中针对迟滞现象的建模。基于一阶滞回曲线获得智能作动器的输入输出数据,从理论上研究了经典Preisach模型两种工程上易实现的辨识方法,并应用到一种真实的智能作动器——WIDS-IA压电型作动器,仿真与实验结果表明,两种辨识方法均有效,且误差在同一数量级。为广泛存在迟滞非线性的智能作动器建模提供了理论依据,并具有工程实用价值。  相似文献   
108.
廉租房作为解决城镇低收入家庭住房问题的一种主要渠道,其建设的进展情况并不乐观,在建设模式、资金供应、分配标准等方面仍存在不少问题。为此,需要加强认识、采取多元化融资方式、完善廉租房相关制度,使廉租房建设真正落实到位,从而促进我国住房保障体系乃至整个房地产市场的健康发展。  相似文献   
109.
Public spending is a major policy tool for the government to adjust the macro economic progress. This paper characterizes the effects of shocks in government spending and taxes on Chinese economy growth since 1978. It does so by using a mixed structural VAR (SVAR) approach. Identification is achieved by using institutional information about the tax and spending to identify automatic and discretionary response, and by implication, to infer fiscal shocks. The results show positive government spending shocks as having a positive effect on output, and positive tax shocks as having a negative effects.  相似文献   
110.
邓勇  Liu  Qi  Li  Yixue 《高技术通讯(英文版)》2006,12(1):109-112
0 IntroductionData mining is widely used in many research fieldssuch as decision supporting systems[1], bio-informationanalysis[2]and knowledge engineering[3-5]. Most data col-lected from scientific experiments or telecommunicationnetworks have inherent sequential nature inthemand canthus be abstractly viewed as a sequence of events . Onebasic problemin miningsuchevent sequencesis discoveryof recurrent combinations of events , which are calledepisodes. Once frequent episodes are discovered,rul…  相似文献   
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