基于粗糙-模糊集理论的智能化构件选取

对传统的构件库体系结构进行改进,提出了一种层次型智能构件库体系结构,并在此基础上,提出了一种基于粗糙—模糊集理论的智能化重用构件选取方法,并给出了相应的算法,实例研究表明该方法可以客观地给出重用方案的决策信息,能够提高构件重用的效率和准确率。     

Modeling spent TRISO fuel for geological disposal: corrosion and failure under oxidizing conditions in the presence of water

High temperature gas reactors (HTGRs) are being considered for near term deployment in the United States under the GNEP program and farther term deployment under the Gen IV reactor design (U.S. DOE Nuclear Energy Research Advisory Committee, 2002). A common factor among current HTGR (prismatic or pebble) designs is the use of TRISO coated particle fuel. TRISO refers to the three types of coating layers (pyrolytic carbon, porous carbon, and silicon carbide) around the fuel kernel, which is both protected and contained by the layers. While there have been a number of reactors operated with coated particle fuel, and extensive amount of research has gone into designing new HTGRs, little work has been done on modeling and analysing the degradation rates of spent TRISO fuel for permanent geological disposal. An integral part of developing a spent fuel degradation modeling was to analyze the waste form without taking any consideration for engineering barriers. A basic model was developed to simulate the time to failure of spent TRISO fuel in a repository environment. Preliminary verification of the model was performed with comparison to output from a proprietary model called GARGOYLE that was also used to model degradation rates of TRISO fuel. A sensitivity study was performed to determine which fuel and repository parameters had the most significant effect on the predicted time to fuel particle failure. Results of the analysis indicate corrosion rates and thicknesses of the outer pyrolytic carbon and silicon carbide layers, along with the time dependent temperature of the spent fuel in the repository environment, have a significant effect on the time to particle failure. The thicknesses of the kernel, buffer, and IPyC layers along with the strength of the SiC layer and the pressure in the TRISO particle did not significantly alter the results from the model. It can be concluded that a better understanding of the corrosion rates of the OPyC and SiC layers, along with increasing the quality control of the OPyC and SiC layer thicknesses, can significantly reduce uncertainty in estimates of the time to failure of spent TRISO fuel in a repository environment.     

Recent Waste Management Related Developments in Germany

The Federal Republic of Germany intends to dispose of all types of radioactive waste in deep geological formations. This waste comprises spent fuel elements, vitrified fission products, nuclear power plant operational and decommissioning waste as well as spent sealed radiation sources and miscellaneous waste originating from small waste generators. The Federal Government made a pronounced change in energy policy since 1998, the most important feature of which is the abandoning or phasing out of nuclear energy, finally set in force by the April 2002 amendment of the Atomic Energy Act. According to the new approach to waste management and disposal, further sites in various host rocks shall be investigated for their suitability. A special expert group was set up to develop repository site selection criteria and respective procedures on a scientifically sound basis. The objective of the site selection procedure is to identify—with public participation—potential disposal sites in a comprehensible and reliable way. Step by step and based on the said criteria, those areas, site regions and eventually sites shall be selected, which offer particularly favourable conditions for the later demonstration of the final site's suitability and its confirmation in a licensing procedure.     

一种面向对象的软件复用框架

本文利用面向对象技术,提出了一种面向对象的软件复用框架,该框架采用面向对象的类来实现构件,为了提高构件库的组织管理效率,采用为构件库建立多个索引链等策略,构件检索采用模糊查询和详细查询的两个阶段来实现,构件集成采用基于星型拓扑结构的构件集成方法。     

An evaluation of nuclide release from a trench-type LILW repository

A simple and effective model and a GoldSim (GoldSim, 2006) template program, by which a probabilistic safety assessment of a conceptual trench-type repository for low- and intermediate level radioactive waste (LILW) disposal can be carried out under various nuclide release scenarios, have been developed. To quantify the exposure dose rates due to nuclide release from the trench and transport through the various pathways possible in the near- and far-fields of the repository system under a base case and some alternative scenarios, illustrative evaluations for a comparison among the scenarios as well as a sensitivity of shortcut pathways generated due to earthquakes on the nuclide transport are made and demonstrated. To this end, by changing the conservative base case nuclide release scenario under which all portions of the cap of the trench are failed unconditionally and immediately after a closure of the repository, a total of four other alternative scenarios were separately evaluated for the total exposure dose rates to the farming exposure group and then compared to the base case results. Among them, an earthquake scenario shows a dominant behavior almost throughout the whole time span. To see the influence of all shortcut travel pathways that are assumed to be newly generated by this earthquake scenario, their sensitivities to the exposure dose rates to the farming exposure group were also made and compared to each other.     

基于Simfusion和本体的视频语义提取

目前大多数的视频语义概念提取研究没有考虑到视频多模态之间的关联共生特性,而在样本的标注方面采用自定义的概念进行标注,会影响语义概念提取的准确率。针对上述问题,提出结合Simfusion算法和用本体知识库标注样本的方法提取视频的语义概念,该方法根据镜头内容变化提取关键帧,在提取出镜头内容时,有效地利用镜头多模态之间的时序关联共生特性,同时运用本体知识库中的概念标注样本、训练分类器,弥补传统方法在标注样本时存在的主观、不规范等不足。实验结果表明,该方法在视频语义概念提取的研究中,有较高的准确度、可操作性强。     

产品设计知识库及特征识别系统构造

利用POWERBUILDER构成了GPAL－CAD知识库系统，并介绍了其系统组成、功能、理论基础，结构设计，以及部分界面设计等。改以往的事后建议为主动设计支持的思路，以及为完成这一目标而引起的数学模型的变化和知识库的具体组织、构造等，并构造了特征识别系统，对工程图纸进行识别进行，作为知识库的辅助系统。     

Sensitivity analysis on the thermal-hydraulic parameters governing the saturation of an engineered clay barrier system

In this paper, we study the impact a heat source makes on the thermo-hydraulic behaviour of a system composed of an engineered clay barrier and a host rock, namely an argillite. We first perform a benchmark test case with code CAST3M and code ASTER. The results of the calculations are in good agreement, except for the gas pressure. Nevertheless, gas pressure does not seem to influence the saturation process, although the saturation kinetics is governed by the darcean water flow. The saturation process is accelerated when the heat source is taken into account. More precisely, this acceleration is due to dynamic viscosity increase with heating. In a second time, five other heating sources have been tested in code ASTER. Compared with the reference calculations, some give an identical response. However, the highest heating sources provoke a desaturation phenomenon because of the air pressure increase with temperature. The liquid saturation of the engineered barrier is then delayed.     

ConceptBase — A deductive object base for meta data management

Deductive object bases attempt to combine the advantages of deductive relational databases with those of object-oriented databases. We review modeling and implementation issues encountered during the development of ConceptBase, a prototype deductive object manager supporting the Telos object model. Significant features include: 1) The symmetric treatment of object-oriented, logic-oriented and graph-oriented perspectives, 2) an infinite metaclass hierarchy as a prerequisite for extensibility and schema evolution, 3) a simple yet powerful formal semantics used as the basis for implementation, 4) a client-server architecture supporting collaborative work in a wide-area setting. Several application experiences demonstrate the value of the approach especially in the field of meta data management.     

一种基于构件的移动警务系统的扩展性设计

通过对业务扩展需求的分析,结合基于构件的软件开发方法思想,提出了一种基于构件的移动警务系统的扩展性设计方案,分别对客户端和服务端进行了构件化设计。在客户端设计上,抽象了一组警务系统专用的界面构件和事件处理构件;在服务端的设计上,抽象了一组警务系统专用的业务构件。改良后的系统在透明性、灵活性、高效性和扩展性等方面都得到了提高,使得终端用户更加便利。