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941.
证券内幕交易是证券市场中经常发生的、危害极大的一种经济犯罪行为。本文主要论述了内幕交易的犯罪构成,从内幕信息、内幕信息知情人员的范围、内幕交易的主观方面、客观方面等环节重新梳理内幕交易罪。  相似文献   
942.
爆炸冲击波作用下核电站安全壳动力分析模型   总被引:5,自引:0,他引:5  
根据某国防科研课题,建立核电站安全壳在爆炸冲击波作用下的动力分析模型,讨论并分析了质点杆模型在安全壳预应力混凝土结构中的应用。质点杆模型可用于计算爆炸冲击波作用下的结构响应。  相似文献   
943.
1 IntroductionThehighmechanicalproperties ,gooddurabilityandappropriateworkabilityarenecessaryforhighperformanceconcretetosatisfytheconstructionrequirementoflarge scaleconcreteengineering .Accordingtodifferentapplica tionsandpurposes ,inordertoimprovethe…  相似文献   
944.
TiO2 fims have been deposited on glass substrates using DC reactive magnetron sputtering at different oxygen partial pressures from 0. 10 Pa.to 0.65 Pa. The transmittance (UV-vis) and photoluminescence (PL) spectra of the films were recorded. The results of the UV-vis spectra show that the deposition rate of the films decreased at oxygen partial pressure P(O2)≥0.15 Pa, the band gap increased from 3.48 eV to 3.68eV for direct transition and from 3.27 eV to 3.34 eV for indirect transition with increasing the oxygen partial pressure. The PL spectra show convincingly that the transition for films was indirect, and there were some oxygen defect energy levels at the band gap of the films. With increasing the O2 partial pressure, the defect energy levels decreased. For the films sputtered at 0.35 and 0.65 Pa there were two defect energy levels at 2.63 eV and 2.41 eV, corresponding to 0.72 eV and 0.94 eV below the conduction band for a band gap of 3.35 eV, respectively. For the films sputtered at 0.10 Pa and 0.15 Pa, there was an energy band formed between 3.12 eV and 2.06 eV, corresponding to 0.23 eV and 1.29 eV below the conduction band. ZHAO Qing-nan : Born in 1963 Funded by Natural Science Foundation of Hubei Province, China.  相似文献   
945.
The hydration characteristics and expansion impetus of three kinds of cement paste under free-and confined-curing conditions were investigated, which were respectively mixed with three different kinds of expansive agent at low W/B ratio. The results show that the hydration products of pure cement paste and paste mixed with expansive agent are same, but the amount of hydration products, un-hydrated C3S and C2S are obviously different at the same hydration age. At 3 d age, the amount of CH in pure cement paste is less than that of paste mixed with expansive agent, but it is reverse when at 28 d age. The amount of AFt at 3d and 28d age in pure cement paste is less than those of paste mixed with expansive agent. Regardless of under free- or confined-curing condition, the amount of ettringite produced varies little since 3d age. The joint effect of the tumefaction of gel-ettringite due to water absorption and the expansive pressure on the pore caused by the crystalloid ettringite is the cause of the volume expansion of cement paste, and the former effect is much greater than the latter. LU Lin-nu : Born in 1972 Funded by 973 High-tech Project of China (No. 2001CB610704-2) and the Natural Science Foundation of Hubei Province(No. 2002AB075)  相似文献   
946.
iButton技术在安防系统中的应用   总被引:2,自引:0,他引:2  
本文介绍了一种新型的智能化信息载体iButton以及iButton在安防系统上的应用举例,着重介绍了其硬件、软件设计及工作原理。  相似文献   
947.
SATCHMORE was introduced as a mechanism to integrate relevancy testing with the model-generation theorem prover SATCHMO. This made it possible to avoid invoking some clauses that appear in no refutation, which was a major drawback of the SATCHMO approach. SATCHMORE relevancy, however, is driven by the entire set of negative clauses and no distinction is accorded to the query negation. Under unfavorable circumstances, such as in the presence of large amounts of negative data, this can reduce the efficiency of SATCHMORE. In this paper we introduce a further refinement of SATCHMO called SATCHMOREBID: SATCHMORE with BIDirectional relevancy. SATCHMOREBID uses only the negation of the query for relevancy determination at the start. Other negative clauses are introduced on demand and only if a refutation is not possible using the current set of negative clauses. The search for the relevant negative clauses is performed in a forward chaining mode as opposed to relevancy propagation in SATCHMORE which is based on backward chaining. SATCHMOREBID is shown to be refutationally sound and complete. Experiments on a prototype SATCHMOREBID implementation point to its potential to enhance the efficiency of the query answering process in disjunctive databases. Donald Loveland, Ph.D.: He is Emeritus Professor of Computer Science at Duke University. He received his Ph.D. in mathematics from New York University and taught at NYU and CMU prior to joining Duke in 1973. His research in automated deduction includes defining the model elimination proof procedure and the notion of linear resolution. He is author of one book and editor/co-editor of two other books on automated theorem proving. He has done research in the areas of algorithms, complexity, expert systems and logic programming. He is an AAAI Fellow, ACM Fellow and winner of the Herbrand Award in Automated Reasoning. Adnan H. Yahya, Ph.D.: He is an associate professor at the Department of Electrical Engineering, Birzeit University, Palestine. He received his Diploma and PhD degrees from St. Petersburg Electrotechnical University and Nothwestern University in 1979 and 1984 respectively. His research interests are in Artificial Intelligence in general and in the areas of Deductive Databases, Logic Programming and Nonmonotonic Reasoning in particular. He had several visiting appointments at universities and research labs in the US, Germany, France and the UK. Adnan Yahya is a member of the ACM, IEEE and IEEE Computer Society.  相似文献   
948.
The goal of this research was to operationalize the information technology infrastructure (ITI) concept by identifying its underlying dimensions and establishing a valid and reliable measure for the construct. In order to accomplish this task with the highest degree of certainty, two approaches were sequentially applied: exploratory factor analysis and confirmatory factor analysis. In evaluating the confirmatory factor model, a step-by-step process was employed, assessing unidimensionality, reliability, discriminant validity, and nomological validity. The dimensions of ITI were determined to be: Chief Information Officer, IT Planning, IT Security, Technology Integration, Advisory Committee, Enterprise Model, and Data Administration. Researchers may now make use of this validated ITI measure to conduct investigations of ITI and other organizational measures. Implications of the ITI measure with other organizational initiatives such as electronic commerce and knowledge management are explored.  相似文献   
949.
IPv6的高级套接口规范还在定义之中,不断地增加新的功能。该文根据IPv6接入路由器的实现经验,提供给大家新一代网络层协议IPv6高级套接口主要功能的实现机制和应用示例。通过对实现机制的分析,文章给出了新增高级套接口功能的实现参考。  相似文献   
950.
Book Review     
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