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151.
B/S结构下研究生培养方案制订系统分析设计 总被引:1,自引:0,他引:1
针对目前研究生培养方案制订过程的复杂性,提出了一种基于Web和三层B/S模式的研究生培养方案制订系统.该系统成功地解决了学校管理、教师制订培养方案和研究生选择课程三者之间的关系.主要讨论了B/S的结构及其工作原理,设计了系统功能图,其中包括系统控制模块、学生管理模块、教师管理模块、课程管理模块和教室管理模块.该系统的应用保证了研究生培养方案的安全性、稳定性和高效性. 相似文献
152.
一个基于语义万维网的应用平台 总被引:2,自引:0,他引:2
为了对语义万维网程序提供支持,构建了一个基于语义万维网应用的平台(SWAP)。介绍了SWAP的存储模型,包括对文本文件的支持、数据库的设计和构建;描述了中间层的应用程序接口的设计,举例阐述了存储模型与核心数据结构的转换,并简单介绍了建立在此基础上的语义知识编辑环境这一特殊应用,SWAP系统为语义万维网程序的开发和运行提供了一个完整的平台。 相似文献
153.
ZHANG Lin CHEN He-ping 《武汉大学学报:自然科学英文版》2006,11(1):57-62
0 IntroductionOonft thhee gcloombaml uinnifcoartimoanti onentiwnofrraksst rhuacstu mread,et ahvea iglraebalte teox puasnesrisolarge number of autonomous data repositories ,however ,these repositories present different structures and semantics result fromthat distinct data sources may use different modeling methodsmaking very difficult to share and exchangeinformation.Recentlythere have been some works ,such as OntoBroker in Ref .[1] ansystemin Ref .[2] ,that focus on the umformrepresentation … 相似文献
154.
HUANG Jianbin JI Hongbing SUN Heli 《武汉大学学报:自然科学英文版》2006,11(5):1177-1181
How to integrate heterogeneous semi-structured Web records into relational database is an important and challengeable research topic. An improved model of conditional random fields was presented to combine the learning of labeled samples and unlabeled database records in order to reduce the dependence on tediously hand-labeled training data. The pro- posed model was used to solve the problem of schema matching between data source schema and database schema. Experimental results using a large number of Web pages from diverse domains show the novel approach's effectiveness. 相似文献
155.
YANGJian-wu 《武汉大学学报:自然科学英文版》2004,9(5):817-822
In this paper, an improved algorithm, named STC-I. is proposed for Chinese Web page clustering based on Chinese language characteristics, which adopts a new unit choice principle and a novel suffix tree construction policy. The experimental results show that the new algorithm keeps advantages of STC, and is better than STC in precision and speed when they are used to cluster Chinese Web page. 相似文献
156.
WUShi-jing GONGZhi-bo YINYong HUANGHe-chao LOUWei-hua 《武汉大学学报:自然科学英文版》2004,9(5):839-844
Making use of Microsoft Visual Studio. NET platform, hierarchical network planning is realized in working procedure time-optimization of the construction by TBM. and hierarchical network graph of the construction by TBM is drawn based on browser. Then the theory of system realization is discussed, six components of system that can be reused are explained emphatically. The realization of hierarchical network panning in Internet provides available guarantee for controlling rate of progress in large-scale or middle-sized projects. 相似文献
157.
KANGDa-zhou XUBao-wen LUJian-jiang WANGPeng LIYan-hui 《武汉大学学报:自然科学英文版》2004,9(5):575-579
This paper introduces the definition and calculation of the association matrix between ontologies, h uses the association matrix to describe the relations between concepls ill different ontologics and uses concept vectors to represent queries; then computes the vectors with the association matrix in order to rewrite queries, This paper proposes a simple method of querying through heterogeneous Ontology using association matrix. This method is based on the correctness of approximate information filtering theory; and it is simple to be implemented and expected to run quite fast. 相似文献
158.
LIUAn-feng CHENZhi-gang LONGGuo-ping 《武汉大学学报:自然科学英文版》2004,9(5):749-754
A new admission control algorithm considering the network self-similar access characteristics is proposed. Taking advantage of the mathematical model of the network traffic admission control which can effectively overcome the self-similar characteristics of tile network requests, through the scheduling of the differential service queue based on priority while at the same time taking into account various factors including access characteristics of requests, load information, etc. smoothness of the admission control is ensured by the algorlthm proposed in this paper. We design a non-linear self-adapting control algorithm by introducing an exponential admission function, thus overcomes the negative aspects introduced by static threshold parameters. Simulation results show that the scheme proposed in this paper can effectively improve the resource utilization of the clusters, while at the same time protecting the service with high priority. Our simulation resuhs also show that this algorithm can improve system stability and reliability too. 相似文献
159.
J.-F. Ripoll A.A. Wray 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,93(4):473-519
We present in this paper a new 3D half-moment model for radiative transfer in a gray medium, called the model, which uses maximum entropy closure. This model is a generalization to 3D of the 1D version recently proposed in (J. Comp. Phys. 180 (2002) 584). The direction space Ω is divided into two pieces, Ω+ and Ω-, in a dynamical way by the plane perpendicular to the total radiative flux, and the half moments are defined from these subspaces. The model closure and the integrations of the radiative transfer equation performed on the moving Ω± spaces are detailed. 1D planar results, which have motivated the extension of the model of (J. Comp. Phys. 180 (2002) 584) to multi-dimensions, are shown. These results are very good. The model is thereafter derived for 3D spherically symmetric geometry, where the correctness of the non-trivial border terms can be checked. Two 3D spherically symmetric problems are numerically solved in order to show the accuracy of the closure and the role of the border terms. Once again, compared to the solution obtained with a ray tracing solver, results are very good. From the 3D half-moment model, a new moment model, called , is derived for the particular case of a 3D hot and opaque source radiating into a cold medium, for applications such as simulations of stellar atmospheres and fires. Two-dimensional numerical results are presented and compared to those obtained solving the RTE and with other moment models. They demonstrate the very good accuracy of the model, its good convergence properties, and better prediction compared to all other existing moment models in its domain of applicability. 相似文献
160.
Xu Xiaoyong Zheng Guoguang Wang Qing-an 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,92(1):61-72
This paper experimentally and theoretically examines the scattering properties of simulated non-spherical hydrometeors including water oblates, ice oblates and ice sphere-cone-oblates, in terms of the backscattering cross-section and the differential reflectivity. The experimental measurements of the backscattering cross-sections of non-spherical hydrometeor samples were performed in the Electromagnetic Scattering Laboratory of China National Space Industrial Corporation. Meanwhile, the backscattering cross-sections have been computed with the transition (T) matrix method. The theoretical results are compared with the experimental data, showing that the calculations are consistent with the observations in general. Experimental and theoretical analyses indicate that the backscattering cross-section of non-spherical particles increases as the particle size parameter increases, and fluctuates when the sizes are larger under the effect of resonance scattering. Differential reflectivity ZDR of water oblates in natural rainfall is always greater than 0 dB whereas ZDR of hailstones may be negative. There is a good linear relationship between differential reflectivity and aspect ratio of a particle. These derivations agree with the literature and can be used to identify the presence of hail particles and distinguish between plate-type and columnar-type hydrometeors. In this study, the measuring experiment and the T-matrix method calculations for the scattering of simulated raindrop and ice particles are also briefly described. 相似文献