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一种分布式实时系统软件体系结构 总被引:3,自引:0,他引:3
针对分布式实时系统的软件体系结构进行了深入研究,试图为应用开发者提供一个开发分布式实时系统的通用框架,首先提出由事件总线和数据访问总线组成具有开放结构的分布式实时系统的参考模型,然后详细讨论了事件总线和数据访问总线的组成成分,工作原理和工作过程,最后,研究了支持平台的单一映象编程模型,实时QoS的支持,提供主动服务机制,灵活开放的系统结构等技术特点。 相似文献
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一种基于策略的软件自适应框架 总被引:1,自引:0,他引:1
普适计算成为一种新的应用模式,普适计算运行环境的复杂性对软件自适应提出了新的挑战.提出一种基于策略的软件自适应框架,该框架采用基于上下文的自适应策略模型及上下文驱动的事件机制实现软件运行的自适应能力,该框架屏蔽了软件运行环境的复杂性,具有较强的可扩展性. 相似文献
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文章提出了一种新型远程作业管理系统框架。该框架基于JMX架构,融合了基于企业权限映射模型的安全机制、JSF(JavaServerFace)的可视化框架等多项技术,有效地改进了传统的作业管理系统的可扩展性差、安全机制不足和缺乏统一、完善的系统管理三点不足。并基于该框架实现了国家863项目“远程作业管理系统”,实现了灵活的系统组件动态配置,基于企业权限映射模型的高安全和可视化管理界面,比较了实现系统和传统系统的优点,讨论了其中涉及到的关键技术。 相似文献
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实时主动数据库中的事件 总被引:12,自引:0,他引:12
主动数据库系统一般采用触发器机制实现系统的主动能力,而事件则是触发器机制中的重要部分。本文讨论实时主动数据库系统ARTs-I中事件的概念、结构与说明以及事件探测与复合事件的处理;提出了一种支持实时应用的S-A触发器模型;将定量限制与时间事件统一起来,使定时机制与主动数据库更紧密地结合为一体。 相似文献
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事件抽取旨在把含有事件信息的非结构化文本以结构化的形式予以呈现。现有的基于监督学习的事件抽取方法往往受限于数据稀疏和分布不平衡问题,具有较低的召回率。针对这一问题,该文提出一种利用框架语义优化事件抽取的方法,引入框架类型作为泛化特征,在此基础上进行框架类型和事件类型的映射,然后结合框架类型识别模型和事件类型识别模型进行协作判定,以此优化事件抽取的召回性能。实验结果显示,针对触发词(事件类型)识别任务,相较于仅使用事件类型识别模型,该文提出的框架语义辅助的事件类型识别模型能够提高抽取召回率6.44%(5.74%),提高F值1.45%(0.83%)。 相似文献
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全面分析了车辆异常行为的识别及交通流参数采集处理方法,提出构建具备二级报警机制的交通事件自动识别系统框架模型.该系统可充分利用高速公路目前已有的监测设备作为系统数据采集的前端设备,提高交通事件检测的准确性和可靠性,减少二次事故的发生. 相似文献
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Recently, many fuzzy time series models have already been used to solve nonlinear and complexity issues. However, first-order fuzzy time series models have proven to be insufficient for solving these problems. For this reason, many researchers proposed high-order fuzzy time series models and focused on three main issues: fuzzification, fuzzy logical relationships, and defuzzification. This paper presents a novel high-order fuzzy time series model which overcomes the drawback mentioned above. First, it uses entropy-based partitioning to more accurately define the linguistic intervals in the fuzzification procedure. Second, it applies an artificial neural network to compute the complicated fuzzy logical relationships. Third, it uses the adaptive expectation model to adjust the forecasting during the defuzzification procedure. To evaluate the proposed model, we used datasets from both the Taiwanese stock index from 2000 to 2003 and from the student enrollment records of the University of Alabama. The results of our study show that the proposed model is able to obtain an accurate forecast without encountering conventional fuzzy time series issues. 相似文献
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The paper discusses the development of a prototype solid modeling system based on the extended octree modeling approach and its applications in 3-D NC machining simulation and automatic verification. Along with a simple hierarchical data structure, the extended octree model uses the face boundary information (i) to represent complex objects, (ii) to improve object representational accuracy, and (iii) to accelerate the model updating procedures in a graphic simulation process. The improved representational accuracy makes it possible to carry out automatic NC program verification by generating the machined model of the part through the simulation and comparing it with the designed model of the part. The paper also addresses the issues of model conversions from CSG and B-Rep schemes to the corresponding extended octree models and the issues of carrying out Boolean operations on those extended octree models. A prototype system has been implemented and is integrated with AutoCAD AME solid modeler for object modeling and for NC simulation purpose. 相似文献
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《Information and Software Technology》2005,47(11):747-760
This paper discusses the issues involved in evaluating a software bidding model. We found it difficult to assess the appropriateness of any model evaluation activities without a baseline or standard against which to assess them. This paper describes our attempt to construct such a baseline. We reviewed evaluation criteria used to assess cost models and an evaluation framework that was intended to assess the quality of requirements models. We developed an extended evaluation framework and an associated evaluation process that will be used to evaluate our bidding model. Furthermore, we suggest the evaluation framework might be suitable for evaluating other models derived from expert-opinion based influence diagrams. 相似文献
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孙虎 《数字社区&智能家居》2007,2(8):390-392
网络应用系统或数据库管理系统安全管理中一个重要问题就是访问控制,本文对传统的自主访问控制模型、强制访问控制模型和基于角色的访问控制模型等几种主流模型进行了介绍,并在最后详细分析和介绍了RBAC96模型. 相似文献
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Francesca Carmagnola Federica Cena Cristina Gena 《User Modeling and User-Adapted Interaction》2011,21(3):285-331
Nowadays a large number of user-adaptive systems has been developed. Commonly, the effort to build user models is repeated
across applications and domains, due to the lack of interoperability and synchronization among user-adaptive systems. There
is a strong need for the next generation of user models to be interoperable, i.e. to be able to exchange user model portions
and to use the information that has been exchanged to enrich the user experience. This paper presents an overview of the well-established
literature dealing with user model interoperability, discussing the most representative work which has provided valuable solutions
to face interoperability issues. Based on a detailed decomposition and a deep analysis of the selected work, we have isolated
a set of dimensions characterizing the user model interoperability process along which the work has been classified. Starting
from this analysis, the paper presents some open issues and possible future deployments in the area. 相似文献
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描述了访问控制和逻辑的关系,并将访问控制授权判决问题归约成逻辑蕴涵问题;总结了基于逻辑的访问控制的基本逻辑问题,即逻辑基础、可判定性和安全性分析;分析了一些访问控制模型的基本逻辑问题,包括基于身份的访问控制模型、基于信任管理的访问控制模型和基于属性的访问控制模型;指出了结构化属性描述能力和安全性分析是基于逻辑的访问控制需要进一步研究的问题. 相似文献
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Ting-Peng Liang 《Decision Support Systems》1985,1(3):221-232
Because of the increasing complexity of the problems faced by decision makers and the nature of decision support systems, decision models are becoming more and more crucial to their success. In this paper, a general framework for model management, which can integrate model management and data management and handle issues in model management such as model creation, model modification and model use is proposed. 相似文献