基于OGSA的地震网格监控系统研究

地震网格利用网格技术将地理上分布的各种地震实验设备和现场、数据、人员联结起来,构成一个虚拟的地震研究社区.有效地监控可以促进网格系统的合理开发和部署,提高网格管理水平和资源利用率.分析和比较了端.端、网格监控系统体系结构(GMA)和开放网格体系结构(OGSA)等几种框架,给出了基于OGSA的地震网格监控系统的总体结构,最后对实现的关键技术进行了探讨.     

Web-based distributed system and database modeling for concurrent design

This research introduces a new approach for Web-based collaborative concurrent design. In this approach, systems, product libraries, and product databases for modeling different product development life-cycle aspects are distributed at different locations that are linked through the Web. Product modeling libraries are described as class features. A class feature at a remote location can be used for defining a new class feature at the local site. Product modeling systems distributed at different locations are used for creating product databases that are described by instance features. A system at one location can be implemented using the functions provided at other locations as the components. Different life-cycle databases at different locations are associated by their relations. The optimal design considering relevant life-cycle aspects is identified using the distributed product life-cycle modeling systems and databases.     

Deploying Web-based visual exploration tools on the grid

Grid-based computing facilitates access to different resources. But management in a grid-based environment isn't centralized. To use grid resources effectively, researchers need a central access point to manage the resources, provide a visual means to explore the data, and record these explorations for further investigation and dissemination. This article describes such a system that's being developed jointly by the University of California, Davis, and the Lawrence Berkeley National Laboratory (LBNL). The centralized system acts as a portal into grid-enabled visualization systems. Scientists using the portal can focus on the important task of extracting insights from their data through visualization instead of having to worry about process management. Because scientists at LBNL and their collaborators require access to the portal from around the world, the portal's interface is entirely Web-based. Authenticated users only need a standards-compliant Web browser to explore their data from anywhere in the world. The portal provides a Web-based interface not just for exploring but also for encapsulating visualization data. Encapsulating the process lets users reproduce the visualization results for validation or extend those results by continuing data exploration. We discuss the integration of our grid-enabled visualization server, the visualization Web application that performs the visualization session management, and the Web-based interface.     

BLDC伺服系统控制系统建模与仿真

在分析了永磁无刷直流电机（BLDC）基本运行原理的基础上,建立了BLDC的数学模型,并在MATLAB7.1环境下搭建了伺服系统的双闭环控制系统仿真模型,实验结果表明,该模型在BLDC伺服系统的控制中性能稳定可靠,有较高的实用价值。     

地震网格数据采集与遥现系统设计

数据采集与遥现是地震网格的重要功能,它负责从数据采集设备获取实验数据并传递给远程的实验参与者.分析了开放网格体积结构(OGSA)和数据流服务工具包令牌缓冲网络总线(RBNB),提出了地震网格数据采集与遥现系统的总体框架和工作流程,对数据采集系统的网格服务工厂(GRSF),网格服务实例(GRSI)、对象映射等实现中的关键技术进行了探讨.     

网格环境下的数据库系统

网格计算是一种重要的新技术,网格上的大量数据需要使用数据库系统来管理。在介绍了与网格环境下数据库系统相关的研究工作之后,讨论了网格数据库的研究内容,包括网格数据库管理系统、网格数据库集成和网格应用的新需求。建议数据库研究人员对网格数据库作更多的研究,致力于从网格应用中发现并解决网格数据库面临的新问题。     

网格调度仿真测试环境中自动机模型的研究

网格调度仿真测试环境通过模拟广域范围内的异构资源以及网格中间件的部分功能,为网格调度算法提供了测试环境.自动机模型来源于形式语言与自动机领域,在GridSim的基础上应用自动机模型,设计了仿真处理自动机实现了模拟过程的状态化,使得仿真测试环境具有了层次清晰、可配置和可扩展等优点.     

Unsupervised feature selection and general pattern discovery using Self-Organizing Maps for gaining insights into the nature of seismic wavefields

This study presents an unsupervised feature selection and learning approach for the discovery and intuitive imaging of significant temporal patterns in seismic single-station or network recordings. For this purpose, the data are parametrized by real-valued feature vectors for short time windows using standard analysis tools for seismic data, such as frequency-wavenumber, polarization, and spectral analysis. We use Self-Organizing Maps (SOMs) for a data-driven feature selection, visualization and clustering procedure, which is in particular suitable for high-dimensional data sets. Our feature selection method is based on significance testing using the Wald–Wolfowitz runs test for individual features and on correlation hunting with SOMs in feature subsets. Using synthetics composed of Rayleigh and Love waves and real-world data, we show the robustness and the improved discriminative power of that approach compared to feature subsets manually selected from individual wavefield parametrization methods. Furthermore, the capability of the clustering and visualization techniques to investigate the discrimination of wave phases is shown by means of synthetic waveforms and regional earthquake recordings.     

制造网格环境下的资源建模研究

资源建模是制造网格中资源集成和共享的前提.首先按资源在制造网格中提供的服务类型对其进行了分类,便于对其分类建模.其次提出了由资源层、资源表示层和资源接口层组成的资源层次模型.资源层包括各种物理资源,表示层使用XML Schema封装资源数据和信息,接口层使用Web服务描述语言（WSDL）定义对资源的访问操作.该模型用于将制造资源封装为网格节点,使得制造资源可以方便地接入网格中网络共享.最后以企业标准件库的封装为实例验证了该模型的有效性.     

Performance modeling of parallel applications for grid scheduling

Grids consist of both dedicated and non-dedicated clusters. For effective mapping of parallel applications on grid resources, a grid metascheduler has to evaluate different sets of resources in terms of predicted execution times for the applications when executed on the sets of resources. In this work, we have developed a comprehensive set of performance modeling strategies for predicting execution times of parallel applications on both dedicated and non-dedicated environments. Our strategies adapt to changing network and CPU loads on the grid resources. We have evaluated our strategies on 8, 16, 24 and 32-node clusters with random loads and load traces from a grid system. Our strategies give less than 30% average percentage prediction errors in all cases, which, to our knowledge, is the best reported for non-dedicated environments. We also found that grid scheduling using predictions of execution times from our performance modeling techniques will lead to perfect mapping of applications to resources in many cases.     

网格环境下机载导弹远程测试软件建模

随着技术的发展,机载导弹的维护变得越来越复杂.远程测试是由专家指导维护人员或者由专家直接对机栽导弹进行测试,定位故障.针对远程测试中碰到的防火墙阻塞,平台不独立等问题,提出了基于网格的远程测试.并在分析远程测试中可能发生时序错乱,网络延时等问题的基础上,建立了机载导弹远程测试软件模型.     

A knowledge-based environment for modeling and simulating softwareengineering processes

The design and representation schemes used in constructing a prototype computational environment for modeling and simulating multiagent software engineering processes are described. This environment is called the articulator. An overview of the articulator's architecture identifying five principal components is provided. Three of the components, the knowledge metamodel, the software process behavior simulator, and a knowledge base querying mechanism, are detailed and examples are included. The conclusion reiterates what is unique to this approach in applying knowledge engineering techniques to the problems of understanding the statics and dynamics of complex software engineering processes     

Intelligent Web-based education system for adaptive learning

This paper depicts a set of integrated tools to build an intelligent Web-based education system. Our purpose is to create a Web learning environment that can be tailored to the Learners’ needs. The Web learning environment is composed of Authoring Tool, Evaluation System, Interactive Voice System and a Virtual Laboratory for programming in Java. All tools use Web Services and have the characteristics of powerful adaptability for the management, authoring, delivery and monitoring of learning content. Part of the decision-making inside the intelligent Web-based education system was made with a multi-agent system.     

An evolving system for simulating clothes on virtual actors

This cloth modeling and animation system aims to support virtual actors who can dress and undress themselves. It now creates autonomous clothes, independent of the synthetic human wearing them. The interactive editor, proportion box and body-scaling feature provide a set of intuitive tools for animators to design a rich variety of human shapes, and we have shown how to dress them with autonomous clothes. The new software considerably improves system performance, versatility and ease of use, and our goal of simulating actors that can dress and undress themselves is significantly closer     

Supervised fuzzy logic modeling for building earthquake hazard assessment

Building hazard assessment prior to earthquake occurrence exposes interesting problems especially in earthquake prone areas. Such an assessment provides an early warning system for building owners as well as the local and central administrators about the possible hazards that may occur in the next scenario earthquake event, and hence pre- and post-earthquake preparedness can be arranged according to a systematic program. For such an achievement, it is necessary to have efficient models for the prediction of hazard scale of each building within the study area. Although there are subjective intensity index methods for such evaluations, the objective of this paper is to propose a useful tool through fuzzy logic (FL) to classify the buildings that would be vulnerable to earthquake hazard. The FL is a soft computing intelligent reasoning methodology, which is rapid, simple and easily applicable with logical and rational association between the building-hazard categories and the most effective factors. In this paper, among the most important factors are the story number (building height), story height ratio, cantilever extension ratio, moment of inertia (stiffness), number of frames, column and shear wall area percentages. Their relationships with the five hazard categories are presented through a supervised hazard center classification method. These five categories are “none”, “slight”, “moderate”, “extensive”, and “complete” hazard classes. A new supervised FL classification methodology is proposed similar to the classical fuzzy c-means procedure for the allocation of hazard categories to individual buildings. The application of the methodology is presented for Zeytinburnu quarter of Istanbul City, Turkey. It is observed that out of 747 inventoried buildings 7.6%, 50.0%, 14.6%, 20.1%, and 7.7% are subject to expected earthquake with “none”, “slight”, “moderate”, “extensive”, and “complete” hazard classes, respectively.     

Statistical modeling and feature selection for seismic pattern recognition

Application of pattern recognition techniques to reflection seismic data is difficult for several reasons. The amount of available training data is limited by the degree of well control in the area and may not be sufficient. In contrast, seismic data sets are often extremely large, necessitating the use of the smallest possible feature set to allow quick and efficient processing. In this paper, a method to generate synthetic training data is described, which alleviates the problem of insufficient training data. A means is provided for injecting a priori geologic knowledge into the classifier, including well logs. Finally, a feature evaluation algorithm using a performance metric related to the Bayes probability of error is outlined and applied to the training data to identify effective feature sets.     

基于构件网格的农业专家系统研究

在农业Web服务器中存在大量的智能化构件资源,常规的服务组织方式不利于这些构件之间的协同服务和分发,基于构件网格提出农业专家系统的模型驱动体系结构,分析了分布式构件问的集成规则,并研究了数据挖掘构件、推理机构件和构件组装的接口问题及专家系统构件组装的实现方案,对构件资源的描述信息采用Web服务技术标准,为Internet上的这些构件资源提供统一的访问和组装方法,以方便挖掘过程中代理对构件的获取应用。     

Finite volume method on the unstructured grid system

Applying the Voronoi diagram to the cell system for the finite volume method, a new method on the unstructured grid system is devised for the simulation of incompressible steady flow. In this method, the SIMPLE algorithm can be applied with little expansion. The turbulent flow around the two-dimensional vehicle model is simulated with the k-ε turbulence model by this method. Comparing the calculation result with another result obtained using the structured grid system and the experimental data, the new method is shown to be suitable for the simulation of complex flow fields.     

A unified framework for modeling, simulating and explaining engineering systems

We present a unified framework which suffices to represent and manipulate physical objects and their relevant relations interactively in the context of modeling, simulating and explaining engineering systems, and which is demonstrated by an example of modeling river networks--environmental engineering systems[9].     

基于网格的垃圾邮件过滤系统

目前实际应用的垃圾邮件过滤技术效果不太理想,尤其是对垃圾邮件的误判率和漏判率问题较为突出.其中,基于概率统计的简单贝叶斯分类算法相对而言效果较好.为提高垃圾邮件过滤系统的分类准确率和效率,利用网格技术资源高度共享的优势,并对Bayes分类算法的应用模式进行改进,提出了一种基于网格的垃圾邮件过滤系统方案.