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1.
为解决传统嵌入式数据库系统只支持基本的事务操作,使得系统无法满足实时性应用需求的问题,分析了实时系统的特点和要求,并综合嵌入式数据库系统事务管理机制,提出了实时事务管理器作为嵌入式数据库系统的实时性解决方案,该管理器的核心算法包括事务截止期分析、事务优先级动态分配策略、事务调度策略和事务接纳策略几个部分。通过应用于嵌入式数据库管理系统Tyche_DB可知,该系统具备了实时系统的特点,满足实时性应用的需求。  相似文献   

2.
多媒体数据库系统的研究与设计   总被引:1,自引:1,他引:0  
在分析研究多媒体数据库系统的体系结构、关键技术、多媒体数据模型、功能及特点的基础上,设计了煤矿系统中的多媒体数据库系统并开发了相应的基于图形界面的煤矿管理系统。在开发系统的过程中,分析了传统的数据库系统的各种解决方案的基础上,主要从数据模型建立、物理结构设计、基于内容的检索等方面给出了较好的解决方案。  相似文献   

3.
基于嵌入式数据库的电力负荷管理终端设计与实现   总被引:1,自引:0,他引:1  
分析了电力负荷管理终端的功能需求;提出了基于嵌入式数据库的电力负荷管理终端的解决方案;在研究了嵌入式据库SQLite内部结构的基础上,设计了电力负荷管理终端的数据库系统;实现了基于嵌入式数据库SQLite的电力负荷管理终端的软件系统。  相似文献   

4.
嵌入式视频传输系统的开发   总被引:1,自引:0,他引:1  
将图像的采集、编码、传输和嵌入式系统开发相结合,构建出一个功能丰富、可灵活应用、稳定运行的实时图像传输系统是一项非常有意义和具有实际应用价值的工作。该文在此基础上完成了一个视频实时传输系统的开发,并重点分析了,嵌入式系统开发中的一些问题。  相似文献   

5.
SQLite嵌入式数据库系统的研究与实现   总被引:8,自引:0,他引:8  
本文在分析嵌入式数据库特性的基础上,阐述了嵌入式数据库的体系结构。介绍了运用SQLite在Linux平台下进行嵌入式数据库开发的方法。探讨了用Qt开发嵌入式数据库图形界面的基本方法,简要介绍了后台数据库的配置及通信机制。最后完成了嵌入式数据库系统的构建。  相似文献   

6.
在嵌入式实时数据库系统中,实时事务执行效率的高低直接影响着整个数据库系统性能的好坏。因此有必要对嵌入式实时事务进行有效预分析和预处理,以支持实时事务实现定时限制。文章给出了一种基于功能替代并且考虑实时事务定时性、功能替代性、多种相关性的实时事务提交策略,大大提高了实时事务执行的成功率。  相似文献   

7.
基于移动数据库的事务处理模型的研究   总被引:1,自引:0,他引:1  
赵旸 《计算机工程》2006,32(5):68-70,79
对移动数据库的关键技术之一事务处理进行了分析与探讨。在分析现有移动事务处理模型的基础上,结合研究开发的嵌入式移动数据库系统SwiftDB,提出增加接入代理层的事务处理系统结构,并根据移动计算环境的特点和具体应用需求,分析了移动节点上事务状态,改进两级复制模型的移动事务解决方案。  相似文献   

8.
嵌入式实时软件具有实时性、多样性的特点,使之广泛应用于各个领域。然而随着人们对软件智能化需求的提高,软件开发的难度和成本逐渐加大,构件化本文在详细分析构件化软件开发技术的基础上,结合嵌入式实时软件的开发特点、开发环境等方面对嵌入式实时软件的框架结构进行了系统的分析研究。  相似文献   

9.
嵌入式实时数据库系统的存储管理   总被引:18,自引:0,他引:18  
本文针对嵌入式系统的应用环境和实时数据库系统的数据特征,通过对各种存储器性能的比较,提出了嵌入式实时数据库系统的存储体系结构.在此基础上,对读写速度不对称且写次数有限的存储器提出了一种合理的文件系统的物理结构和数据库的索引结构,减少写入次数以提高数据存取速度,并使写入次数均匀分布在存储器的各块中,以增加数据的可靠性延长存储器的寿命.对实时数据库的不同特征的数据的在本存储体系的安置也进行初步的讨论.  相似文献   

10.
基于遗传算法的实时内存数据库查询优化   总被引:3,自引:0,他引:3  
各种事务类型的查询处理是实时数据库实现的关键点之一.由于现有的关系查询处理不能适合于实时数据库,因此实时数据库系统必须具有自己的查询处理器.为此,结合正在开发的嵌入式实时数据库系统ERTDBMS,给出了一个实时数据库查询处理的系统RTQP,并在对实时数据库查询处理做了一般性探讨后,将重点放在内存代价和遗传算法上,类似于关系系统RTQP提供了在MMDB环境下节省内存的查询处理的实现算法,以及遗传算法和实时数据库规则相结合的查询优化方案。  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

18.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

19.
基于复小波噪声方差显著修正的SAR图像去噪   总被引:4,自引:1,他引:3  
提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。  相似文献   

20.
蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。  相似文献   

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