网络存储系统的构建及应用

本文分析了DAS、NAS、SAN三种网络存储系统模式,阐述了网络教学平台网络存储系统的需求,并且结合本校实际,提出了基于网络教学平台的存储区域网络系统构建方案.     

ENBD：扩展的网络磁盘设备

网络磁盘设备(Network Block Device,NBD)是一种稳定、高效的开源网络存储软件,可被用于构建基于Linux平台的网络存储系统.网络存储系统一般较为复杂,包含的模块通常要兼有多种功能,而NBD只能完成普通数据的网络传输,缺少网络存储系统要求的集群化、扩展性、元数据操作等功能.该文描述如何扩展NBD,使之成为适合蓝鲸集群文件系统的网络存储软件.     

基于以太网的存储虚拟化研究

存储区域网络（SAN）是新一代网络存储应用技术之一。为了解决IP网络同存储区域网络（SAN）的和互操作的问题，IETF特别成立了IPS（IPStorage）小组，提出了几种基于IP的网络虚拟存储解决方案和相关协议。存储虚拟化是存储系统的主要发展趋势之一，它极大的方便了用户对存储资源的使用．减少存储系统管理开销，优化存储系统性能，提高存储资源利用率。     

面向NAP的存储系统

提出了基于网络的智能存储系统，讨论了网络存储控制器的结构、网络存储的原型系统以及适用干网络存储系统的物理互联和高级协议。     

内网核心数据集中存储系统的设计与应用研究

随着信息化建设的不断深入,以 IP 网络为承载平台的信息系统快速发展,数据业务、流媒体业务大规模增长。在实际工作中,很多单位的内部网络基本上都没有统一的存储系统用于核心数据的存储,数据信息仍分散存储在各设备和计算机终端上,不利于数据的集中管控,凸显了最为核心的安全问题。基于自主可控技术的国产化平台,我们研制了数据集中存储系统,可提供网络数据的集中存储,解决信息零散分布存储,管理者无法集中管控的问题。     

基于凌动平台的网络存储教学案例设计与实现

兰州大学为计算机相关专业本科生开设存储技术相关课程,结合当前Intel凌动处理器平台的推广,设计和实现网络存储实验教学案例。该案例以构建网络存储系统为整体目标,基于Intel凌动处理器平台,涵盖嵌入式Linux系统和iSCSI等技术内容,以充分提升学生对存储系统的认知和动手能力。     

网络光盘库模型的建立和分析*

网络存储技术的广泛应用为近线存储设备应用于海量存储系统提供了新思路,而网络光盘库正是一种利用网络存储技术的新的存储方式。研究了可以通过IP网络接入海量存储系统中的网络光盘库的排队网络模型,并对其进行了仿真模拟,为光盘库在海量存储系统中的应用、设计和性能优化提供理论方法和实验依据。     

基于iSCSI OSD存储系统的设计与分析

iSCSI是一种高效的、高可扩展的存储协议,而对象存储系统是一种新兴的跨平台、安全性的网络存储架构。设计实现的基于iSCSI OSD存储系统,充分发挥了两者的优点。实验测试证明该系统具有较高的存储性能。     

构建安全的分布式网络存储系统

传统的网络存储系统采用集中的存储服务器存放所有数据，使得存储服务器成为系统性能瓶颈和可靠性、安全性的焦点，不能满足大规模存储应用的需要。分布式网络存储系统采用可扩展的系统结构，利用多台存储服务器分担存储负荷，利用位置服务器定位存储信息，它不但提高了系统的可靠性、可用性和存取效率，还易于扩展。本文从系统结构、实现方法、安全策略和效率、可靠性分析等方面对分布式存储系统进行了探讨。     

虚拟网络存储系统自适应数据分配策略

在虚拟网络存储系统中通常包含各种异构的存储设备节点。基于同构系统的传统数据分配和放置策略并不能针对异构存储设备的性能差异来进行数据分配，降低了虚拟网络存储系统的性能。该文提出一种自适应的数据分配策略，能够根据存储设备节点的性能差异有效地进行数据分配。实验证明，该策略能够充分发挥异构存储设备的性能，有效解决虚拟网络存储系统的数据放置不平衡问题，提高虚拟网络存储系统的利用率。     

Only connect: teaching, technology and telesis

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.     

European Community policy and the market

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.     

一种自适应子融合集成多分类器方法

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。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

Avoiding semantic and temporal gaps in developing software intensive systems

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.     

Designing economic np control charts: A programmed simulation approach

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.     

The development of robot art

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     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

Explanation and prediction: an architecture for default and abductive reasoning

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.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.