Virtual and Dynamic Hierarchical Architecture: an overlay network topology for discovering grid services with high performance

This paper presents an overlay network topology called Virtual and Dynamic Hierarchical Architecture (VDHA) for discovering Grid services with high performance. Service discovery based on VDHA has scalable, autonomous, efficient, reliable and quick responsive. We propose two service discovery algorithms. Full Search Query and Discovery Protocol (FSQDP) discovers the nodes that match the request message from all N nodes, which has time complexity O(logN), space complexity O(nvg) (nvg being node numbers of each virtual group), and message-cost O(N), and Domain-Specific Query and Discovery Protocol (DSQDP) searches nodes in only specific domains with time complexity O(nvg), space complexity O(nvg), and message-cost O(nvg). In this paper, we also describe VDHA, its formal definition, and Grid Group Management Protocol.     

网格计算环境下的大学数字化校园基础架构

本文提出了一种基于网格计算环境的数字化校园平台体系基础架构，其中重点介绍了网格技术并且结合数字化校园建设的具体要求，对实现网格计算环境下的数字化校园给出了建议和设计思想。     

A theory of instruction for introductory programming skills

ABSTRACT

Background and Context: Current introductory instruction fails to identify, structure, and sequence the many skills involved in programming.

Objective: We proposed a theory which identifies four distinct skills that novices learn incrementally. These skills are tracing, writing syntax, comprehending templates (reusable abstractions of programming knowledge), and writing code with templates. We theorized that explicit instruction of these skills decreases cognitive demand.

Method: We conducted an exploratory mixed-methods study and compared students’ exercise completion rates, error rates, ability to explain code, and engagement when learning to program. We compared material that reflects this theory to more traditional material that does not distinguish between skills.

Findings: Teaching skills incrementally resulted in improved completion rate on practice exercises, and decreased error rate and improved understanding of the post-test.

Implications: By structuring programming skills such that they can be taught explicitly and incrementally, we can inform instructional design and improve future research on understanding how novice programmers develop understanding.     

基于网格技术的网络学习资源共享

本文首先简略介绍了进行网络学习资源共享的研究的一些背景;其后,对OGSA架构提供的资源共享机制进行了分析,并进而对基于OGSA架构的网络学习资源共享方案进行了高层与技术上的分析;最后,作者给出了相关结论与建议。     

可信计算平台中的密钥管理

综述了可信计算的背景,介绍了可信计算技术的原理,并着重分析了现有的支持可信平台TSS的密钥结构和管理形式。基于这些论述与分析,进一步研究了可信计算的本质内涵,探讨了可信计算平台的可能存在的问题。结合所进行的分析,提出了可信计算的发展建议。     

数字图书馆支撑技术领域标准规范的现状和发展*

数字图书馆的支撑领域涉及多方面的技术，本文对支撑领域中计算模式、Web技术、信息安全的主要标准进行了分析比较，同时探讨了相关标准的发展趋势。     

网络时代的未来--网格技术

网格技术实现了网络资源的全面连通,具有成本低、效率高、使用方便等优点,是21世纪工业技术的又一次革命,它的时代正在来临!     

网格的研究现状

随着互联网技术的飞速发展,被称为第三代互联网的网格时代即将来临.它建立在互联网基础之上,比传统互联网的性能更高、功能更强、应用更广.本文在讨论网格的基本内涵的基础上,着重比较了网格与传统互联网的主要区别,最后介绍了网格的应用领域及发展前景.     

西部区域教育网格系统设计探究

对我国西部地区教育信息化现状进行了调研,发现存在教师技术水平低、资源分布不均、共享不足等问题,针对问题结合网格技术的特点提出了西部区域教育网格系统的构想,并详细阐述了该系统的总体设计、功能设计和资源管理。对促进西部地区教育信息化发展战略起到一定的参考作用。     

基于960网格系统的网页布局实践与研究

960网格系统是一个非常流行的CSS框架,它是国外最成熟的网页布局方法之一,本文主要介绍了它的基本原理及其实现。