基于双向链表的产品协同设计版本存储模型

针对产品协同设计的版本管理的版本存储问题进行研究．在分析了目前已有的版本增量存储和完整存储技术的基础上,提出了一种将完整存储和逆增量存储相结合的产品协同设计版本存储模型．将版本的存储结构按照其父子关系定义为一个双向版本链表,当设计过程产生新的版本时,采用反复迭代和插入的方式,将其存放在版本链表结构中,以实现协同设计版本的快速存储、节约存储空间和提高版本存储的安全性．     

不依赖版本字符串的开源组件版本识别

由于软件代码复用和第三方SDK的广泛使用,开源组件普遍存在于物联网设备固件中.威胁固件的安全漏洞往往存在于组件的某些特定版本中,识别物联网设备固件中开源二进制组件的版本信息,对于物联网的安全评估与应急响应意义重大.现有的基于版本字符串的版本信息提取方法不适用于组件版本字符串缺失的情况.设计和实现了一种不依赖于版本字符串的开源组件版本识别方法Protues.该方法的核心思想是通过开源组件相邻版本源码间的差异构造一条版本差异链,从而将版本识别问题转化为待查组件在版本差异链上的滑动查询问题.进一步地,为了提高识别准确率,采用条件判断表达式来表征版本差异链上的节点.为了验证该方法的实用性,对来自于4种开源组件Samba,Msmtp,Nginx和Libgcrypt的共428个二进制文件进行了版本识别实验,实验结果表明,该方法能够准确识别的版本数达到418个,识别准确率约为98%.     

一种开放式超媒体系统版本模型

本文提出了一种开放式超媒体系统的版本控制模型,它支持版本集、允许可选构件的开发和管理、维护文档的发展历史并且支持协同工作；提出了上下文结点和版本相关表的概念,用以有效地解决结构信息版本和内容信息版本之间的不一致性问题.     

基于基线的软件配置管理版本控制

版本控制是软件配置管理的重要功能,负责为配置库中的所有元素自动分配版本标识,并保证版本命名的惟一性。文中运用软件工程的原理并结合版本控制的实践,首先指出为了有效地进行版本控制而引入基线管理,并通过图形表示最常用的软件项目基线;然后研究版本管理,包括版本管理的功能、版本树、版本的串行与并行演变过程,并通过图形给出了版本演变历史和组件版本的变化过程;最后研究版本控制的主要内容,包括检入检出控制、分支和合并、历史记录。结果表明,在配置管理过程中通过基线进行版本控制,是保护代码资源、提高开发效率、加强软件项目管理的有效途径。     

FlatVC:云环境下虚拟机集群的扁平化版本控制

IaaS的发展使得云服务能够快速地部署虚拟机集群。然而,在部署过程中虚拟机群的版本控制效率不高。目前的版本控制方法存在网络负载大、操作速度慢的问题。提出一种新颖的虚拟机集群版本控制方法,叫做FlatVC。FlatVC在计算节点增量地生成虚拟机版本,以避免将版本数据传输至存储节点,并在虚拟机版本恢复时按需传输版本数据,因此减小了网络传输负载并加速了版本控制过程。通过使用缓存树结构来共享网络传输数据,FlatVC减小了根节点数据传输压力。此外,我们针对增量版本所构成的版本链进行了I/O优化,避免了版本链导致的性能下降。实验结果显示,FlatVC能有效地实施虚拟机集群版本控制,加速版本生成以及恢复过程。     

工程设计数据库管理中版本模型的研究

版本管理是工程数据库管理中的重要部分,也是保证设计数据一致的手段。文中提出了设计对象的概念,以设计对象为基础组织和描述完整的产品设计信息,建立了设计对象之间的组合联系、等价联系以及版本联系,提出了设计对象的层次模型表示方法。针对工程数据管理的特点建立了其版本机制,提出了设计对版本历史、对象版本之间的联系等概念,研究了设计对象的版本操作－检入／检出、当前版本的选择以及版本的动态配置等主要内容。     

基于版本复制的版本存储技术研究

协同图形编辑系统中采用基于版本复制的多版本技术解决编辑过程中冲突操作的意愿保证问题．每个版本存储了在此版本上执行的所有操作,因此存在同一操作被多次存储和版本存储量随编辑过程大规模增加的情况。本文讨论了协同图形编辑系统中基于版本复制的版本存储技术,并给出了一个改进的版本存储模型。     

多版本数据仓库中版本进化的实现

多版本数据仓库中模式进化将产生新的数据仓库版本,直接设计基本的模式进化操作算法来实现数据仓库版本进化会使得算法中包含大量冗余代码,并产生多个重复版本对象。设计进化元操作来实现数据仓库版本的进化,给出了数据仓库版本的一种形式定义以及基于版本对象的三类元操作定义,并用案例说明了通过执行元操作实现数据仓库版本进化的算法思想。进化元操作的设计降低了版本进化算法的复杂性,有利于版本的管理与维护。     

基于3S 技术的青藏铁路数字路基仿真平台应用研究

对于青藏铁路建设和科研活动过程中的数据管理、分析和使用, 以及设计方案仿真评估、决策支持等方面的需求, 青藏铁路数字路基仿真平台的建设可以为之提供有力的支持。针对目标系统的实际应用情况, 通过在建设成本、周期、技术难度等方面的综合权衡, 确定了分别以轻量、重量两个不同的版本, 并以不同的技术手段来实现的总体方案, 以解决不同的需求问题: 轻量版针对野外工作中的数据管理和使用, 以及一定的空间分析和仿真能力; 重量版针对分布式应用和充分的空间分析、仿真, 以及空间决策支持能力。系统建设以GIS 技术为核心, 结合遥感和GPS 技术, 满足了实际应用的需求。     

Consulting support during conceptual database design in the presence of redundancy in requirements specifications: an empirical study

This study examines the efficacy of a consulting system for designing conceptual databases in reducing data modelling errors. Seventy-two subjects participated in an experiment requiring modelling of two tasks using the consulting system. About half the subjects used the treatment version and the other half used the control version. The control version resembled the treatment version in the look and feel of the interface; however, it did not embed the rules and heuristics that were included in the treatment version.Research findings suggest that subjects using the treatment version significantly outscored their control version counterparts. There was an interaction effect between system and prior knowledge—subjects who scored low in a pre-test benefited the most from the treatment version.This study has demonstrated that a consulting system can significantly reduce the incidence of errors committed by designers engaged in conceptual database modelling. Further, the system is robust and can prevent errors even in the presence of redundancy in user requirements.     

Designing educational experiences using ubiquitous technology

The aim of the study was to explore the design of situated educational and compelling experiences using SoundScape technology – which is a ubiquitous technology. Two experiences were designed: one that had a goal and the other that did not. Twenty six children then explored both experiences. The children found that the SoundScape with a goal was more interesting and were more likely to want to have another go than the non-goal version. They also made more positive comments concerning the goal version. Mentioning the presence of a goal as important factor in determining why they liked the game. More negative comments were made concerning the non-goal version and the children mentioned the lack of a goal as negative aspect of the non-goal version. One improvement they suggested for the non-goal version was to add a goal and to include more sensory stimulation. They overwhelmingly preferred the goal version compared to the non-goal version and when asked by far the most popular reason was the presence of a goal.     

面向领域敏捷定制ERP生产中的多级版本管理研究

提出面向领域敏捷定制ERP产品开发模型,重点论述面向领域敏捷ERP定制过程,给出了软件开发过程中的 ERP软件构件版本管理、ERP构件组版本管理以及ERP产品的版本管理模型和详细的解决方案.解决了ERP产品柔性、适应性和ERP产品敏捷生产的问题,为提高我国企业ERP产品的实施成功率,探索出一条新途径.     

面向领域敏捷定制ERP生产中的多级版本管理研究*

提出面向领域敏捷定制ERP产品开发模型,重点论述面向领域敏捷ERP定制过程,给出了软件开发过程中的 ERP软件构件版本管理、ERP构件组版本管理以及ERP产品的版本管理模型和详细的解决方案。解决了ERP产品柔性、适应性和ERP产品敏捷生产的问题,为提高我国企业ERP产品的实施成功率,探索出一条新途径。     

In-place reconstruction of version differences

In-place reconstruction of differenced data allows information on devices with limited storage capacity to be updated efficiently over low-bandwidth channels. Differencing encodes a version of data compactly as a set of changes from a previous version. Transmitting updates to data as a version difference saves both time and bandwidth. In-place reconstruction rebuilds the new version of the data in the storage or memory the current version occupies-no scratch space is needed for a second version. By combining these technologies, we support highly mobile applications on space-constrained hardware. We present an algorithm that modifies a differentially encoded version to be in-place reconstructible. The algorithm trades a small amount of compression to achieve this property. Our treatment includes experimental results that show our implementation to be efficient in space and time and verify that compression losses are small. Also, we give results on the computational complexity of performing this modification while minimizing lost compression.     

协同多版本技术中的中间版本

首先对协同图形编辑的研究现状和存在问题进行了讨论,然后针对并发操作的冲突和分类,在基于版本复制的分布协同多版本技术的基础上,提出了中间版本的存在必要性及其表示和效果显示方法.     

A polynomial time approximation scheme for embedding a directed hypergraph on a ring

We study the problem of embedding a directed hypergraph on a ring that has applications in optical network communications. The undirected version (MCHEC) has been extensively studied. It was shown that the undirect version was NP-complete. A polynomial time approximation scheme (PTAS) for the undirected version has been developed. In this paper, we design a polynomial time approximation scheme for the directed version.     

A layered architecture for uniform version management

Version management is a key part of software configuration management. A big variety of version models has been realized in both commercial systems and research prototypes. These version models differ with respect to the objects put under version control (files, directories, entities, objects), the organization of versions (version graphs versus multidimensional version spaces), the granularity of versioning (whole software products versus individual components), emphasis on states versus emphasis on changes (state-versus change-based versioning), rules for version selection, etc. We present a uniform version model-and its support architecture-for software configuration management. Unlike other unification approaches, such as UML for object-oriented modeling, we do not assemble all the concepts having been introduced in previous systems. Instead, we define a base model that is built on a small number of concepts. Specific version models may be expressed in terms of this base model. Our approach to uniform version management is distinguished by its underlying layered architecture. Unlike the main stream of software configuration management systems, our instrumentable version engine is completely orthogonal to the data model used for representing software objects and their relationships. In addition, we introduce version rules at the bottom of the layered architecture and employ them as a uniform mechanism for expressing different version models. This contrasts to the main stream solution, where a specific version model-usually version graphs-is deeply built into the system and version rules are dependent on this model     

工艺指令版次管理技术实现

分析了航空产品工程数据版次管理以及工艺指令发放管理的模式,提出基于数据发放控制的工艺指令版次管理新思路。建立了工艺指令的版次管理流程,进而阐述了采用信息技术的实现方法。     

一种动态的可认证的群密钥协商方案

为了使群密钥协商协议能够抵抗主动攻击,提出了一种高效的可认证方案。该方案以一种可认证的两方密钥协商协议为基础,首先提出了该协议的无认证版本,然后通过二叉树把两方认证版本、一方认证版本和无认证版本结合起来。该方案提供了隐含密钥认证和完善前向保密等安全属性。其通信开销是常数,计算开销与成员数目的对数成正比。     

Evolving recursive programs by using adaptive grammar based genetic programming

The publisher apologizes for an error that occurred in the above mentioned article. The error appears in the printed version, as well as in the html and pdf version online. Man Leung Wong is the sole author of this article. His affiliation is listed below. The online version of the original article can be found at