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101.
Critical information system in Interact is in face of increasingly security problems. More attention has been focused on the survivability of information system, which is the capability of system to continue its mission even in the presence of damage to the system. The authors first introduce the definition of survivability. According to four function properties of survivability, which are Resistance, Recognition, Recovery, and Adaption, the authors design a model of survivable system structure and then explain survivability requirement, survivability strategy in this model. Additionally, they provide possible technical solutions for the survivability of systems, categorized by different aspects of our survivability strategy.  相似文献   
102.
Employing the standpoint of irrational investors in the behavior finance, the authors study the relation on the irrational behavior of medium and small Investors and underpricing of IPO in our country. The paper premises that a revenue-maximizing issuer will be regarded as the target function, and the rational institutional investors can be delegated the task of holding the stocks in the after-market for resale to the irrational medium and small investors--thereby extracting surplus from them, finally the issuer can maximize their expected revenue. We model the process mentioned above and find that the high underpricing of IPO in our country has the direct relation with numerous the irrational medium and small investors existing in our country who cause the underpricing.  相似文献   
103.
104.
Based on the data of dynamic tests of small single-storey steel frames,the suitability of simplified hi-linear restoring force model in earthquake response analysis is discussed, and the Maximum displacement response MD, the sum of squares of the displacements in the whole vibrating history SSD, and the total dissipated energy EI are considered respectively as equivalent object.  相似文献   
105.
Parameters dominating elasto- plastic earthquake response of SDOF systems,relation between ground motion amplitude and elasto- plastic response of SDOF systems are presented in this paper.  相似文献   
106.
This paper presents the basic equations and algorithm of vehicle crashworthinessbriefly.Take a light-truck for example,some applied problems in ustng Engineering WorkStationto analysis truck crashworthiness are discussed.A installation method of contact surface is intro-duced,Finally,a nurnerical simulation result is presented.  相似文献   
107.
Based on the experimental study of the compound rock's behavior at rock salt's over-layer under single compression and tri-axial compression condition, the basic mechanical properties of the rock have been obtained. It could serve as reference to research work and production.  相似文献   
108.
109.
Pushover analysis is a tool to study the inelastic behavior of structures under strong seismic action. The 3D-pushover analysis was performed to analyze the inelastic lateral-torsional coupled response of multistory asymmetric structures. The symmetric frame and frame-wall systems were studied in this paper, and the capability curve of the top displacement and base shear,the story drift and the position of rotation center were compared with reference to corresponding symmetric structures. The characters of inelastic response of multistory asymmetric structures were found. The conclusion provides reference for performance-based seismic design of asymmetric structures.  相似文献   
110.
小麦花培材料的筛选和利用   总被引:2,自引:4,他引:2  
花培育种是一条快速有效的育种途径,采用两种培养基对20个小麦组合材料进行花培分析,结果表明:小麦花培愈伤组织诱导培养基K优于C17,绿苗产率是C17的3.5倍多。不同基因型材料花药培养差异较大,筛选出一批不同类型的高培养力基因型材料,为有目的组配杂交组合提供依据,提高花培育种效率。  相似文献   
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