基于动态逻辑许可证的PDF版权管理系统

电子文档版权管理是数字版权管理的重要研究领域,提出一种PDF电子文档版权保护方案,该方案的权限管理基于一种具有强大表达力、灵活性和开放权限管理能力的动态逻辑许可证,具有详细的文档权限控制方法,并通过内容级的PDF文档加密方法增强文档的安全性。对系统模型、实现结构和方法进行说明,并与相关方法进行对比和应用示例。     

Document‐centric XML workflows with fragment digital signatures

The use of digital document management and processing is increasing. Traditional workflows of paper forms are being replaced by electronic workflows of digital documents. These workflows often require multiple signatures to be added to the documents for authorization and/or integrity. We describe examples of digital workflows that illustrate problems with digital signatures: i.e. the use of digital signatures across entire documents results in signatures that can be unnecessarily invalidated by subsequent modification of the document. We propose the use of fragment signatures, which reduce unnecessary invalidation of signatures and enable greater concurrency in workflows. Our approach is document‐centric and does not use a centralized database. We report on an implementation that allows fragment signatures over document fragments as well as the attachment (or embedding) of other documents. This allows collaborative or cooperative editing to occur on parts of a document without disturbing unrelated signatures. We describe the lessons learned from our deployments and offer further ways to embed such signatures into other document types. Copyright © 2010 John Wiley & Sons, Ltd.     

Management of access control policies for XML document sources

The development of suitable mechanisms for securing XML documents is becoming an urgent need since XML is evolving into a standard for data representation and exchange over the Web. To answer this need, we have designed Author-X [1, 3], a Java-based system specifically conceived for the protection of XML documents. Distinguishing features of the access control model of Author-X are the support for a wide range of protection granularity levels and for subject credentials. Another key characteristic of Author-X is the enforcement of different access control strategies for document release: besides the traditional, on user demand, mode of access control, Author-X also supports push distribution, for document dissemination. Managing an access control system based on such a flexible and expressive model requires the design and implementation of suitable administration tools to help the Security Administrator in efficiently performing administrative operations related to access control policies management. In this paper, we present the strategies and related algorithms we have devised for policy management in Author-X , with particular emphasis on information push support. In the paper, besides presenting the algorithms and the related data structures, we provide a complexity study of the proposed algorithms. Additionally, we describe the implementation of the proposed algorithms in the framework of Author-X .     

A workflow management system to feed digital libraries: proposal and case study

Building a digital library of antique documents involves not only technical implementation issues, but also aspects related to the digitization of large collections of documents. Antique documents are usually delicate and need to be handled with care. Also, a poor state of preservation and the use of unrecognizable font types make automatic text recognition more difficult, hence requiring a further human revision to perform text corrections. This makes the participation of experts in the digitization process mandatory and, therefore, costly. In this paper, we present a framework for managing the workflow of the digitization of large collections of antique documents. We describe the digitization process, and a tool supporting all of its phases and tasks. We also present a case study in which we describe how the workflow management system was applied to the digitization of more than 10,000 documents from journals of the 19th century. In addition, we describe the resulting digital library, focusing on the most important technological issues.     

Using management procedure gaps to enhance e-learning implementation in Africa

Management of Universities in Ghana have established good rationale for embracing e-learning as a new paradigm of educational delivery, and have demonstrated commitment by investing and building technology infrastructure necessary for e-learning. However, the approach to evaluate the institutional context as guide to successful e-learning implementation remains a problem. In the absence of standards for evaluation to guide the implementation process, this research investigated management approaches to facilitating e-learning implementation at a leading university in Ghana. To gain depth in understanding activities that support e-learning, a pilot survey was conducted. This was used to refine the research instruments. The survey questionnaire, interviews conducted, and institutional documents on e-learning activities provided depth of management practices that supports e-learning. The management procedures were then compared with some e-learning implementation best practice, and gaps were established.This paper has demonstrated that by using dimensional tools to establish procedure gaps in e-learning implementation, the short and long-term strategic plans will be put in perspective. The tool show how the university is moving from its current practices of educational delivery to e-learning or some blend. Universities with problems as discussed in this paper may achieve success by assembling an implementation team and a leader, determining the appropriate learning technology, clearly outlining the process of implementation and having an ongoing evaluation process to institutionalise the innovative e-learning approach. The policy and strategy document, showing the institutional position must include the pedagogical goals, infrastructure requirements, evaluation, collaboration with stakeholders, quality control, technical support, budget and funding and resource planning.     

基于Web Services的数字化制造软资源支撑系统开发

通过分析档案管理系统的开发流程和需求,针对数字化制造软资源管理业务中存在的手工管理为主、设计和生产信息不流畅等管理现状,构建了基于Web Services的数字化制造软资源管理业务流程,提出了基于Web Services的数字化制造软资源支撑系统框架,并设计和实现了该系统。实验结果表明,该系统能够对图纸、文件等纸质、电子文件进行一体化管理,基于Web Services技术是构建数字化制造软资源支撑系统的有效方式。     

A historical and contemporary study on annotations to derive key features for systems design

This paper provides a comprehensive study on annotations by defining their contours and complexity. This work adds a new complementary approach to the usual case and user studies, and also investigates history in order to benefit from previous knowledge and our cultural heritage. This study emphasizes an aspect which has never previously been taken into account: the temporal dimension involved in annotations. Moreover, it discusses both the notion of hypertext between documents and annotations and the idea of annotations as context for documents. The study gives the necessary historical and cultural background to derive a set of key features of annotations that must be taken into account when designing systems that have to support the management of digital annotations on digital contents.     

CoPenML:基于XML的笔式用户界面构件体系结构

笔式用户界面在许多领域得到了广泛应用,但现有的笔式界面技术不能支持高层次、多领域的可视化界面制作,很难实现面向软件构件的重用．因而提出一个新的解决方案,面向构件的体系结构CoPenML．该方案基于XML语言抽象描述了笔式界面的配置组成．可用于快速生成界面原型及二次开发接口,并且在系统实现级以及场景图级两个层面上实现软件构件的重用．设计了CoPenML的体系结构并给出了界面描述语言规范．最后开发了基于CoPenML的笔式界面制作环境以及相关工具．结果表明该方案对于笔式用户界面制作是十分有效的．     

The Digital Reading Desk: A lightweight approach to digital note-taking

Attentive reading is a complex and cognitively demanding task that uses note-taking and annotation to support the reader’s interpretation of the document. When reading on paper, extensive use of highlighting and other activities are conducted to support attentive reading, but this rich behaviour is not used with digital documents. Many users therefore print digital documents and then interact with them in physical form.This paper presents the “Digital Reading Desk,” an enhanced digital reading environment that provides support for attentive reading, providing a large working space for notes that mimics the use of desk space in a conventional physical environment. The Reading Desk uses a single tool to support both annotation and bookmarking, simplifying both the user’s learning of the system and their use of tools. Evaluation of the Reading Desk indicates preference for it, as well as considerable behavioural differences between our approach and traditional digital reading tools.     

基于非确定性数学模型的文本数字水印技术的性能分析

文本数字水印是数字水印技术中的一个分支,好的数学模型可以增强水印的鲁棒性和安全性及效率等技术参数.在文本数字水印的应用中,基于非确定性数学模型的水印技术是一个分支,对该技术的性能进行了详细的分析和评估,指出了这种类型的数字水印的优劣和适用范围,为该类数字水印技术的实际应用提供了理论依据.     

A Secure Scheme for Storage,Retrieval, and Sharing of Digital Documents in Cloud Computing Using Attribute-Based Encryption on Mobile Devices

ABSTRACT

This work describes the analysis, design, and implementation of a secure scheme for storage, retrieval, and fine-grained sharing of digital documents in cloud computing using mobile devices. Confidentiality of digital documents stored in public clouds from a mobile device is achieved by implementing the digital envelope concept. Data are encrypted using AES, and the session key is encrypted using ciphertext-policy attribute based encryption (CP-ABE). CP-ABE also provides access control mechanisms at a fine-grain level, allowing the decryption of the AES key only to those users having the correct set of attributes. The encryption and decryption processes are carried out in a mobile device that interacts with a cloud provider, a trust server, and a key server. For practical implementation of CP-ABE, the Tate pairing was used on elliptic curves type A and F over prime fields, using affine and projective coordinates for the security levels 80, 112, and 128 bits. After evaluating the proposed system for different CP-ABE implementation options, it was observed that the elliptic curves type A allow execution times 18 times faster compared with the use of elliptic curves type F, achieving processing times that ensures the deployment of the proposed secure scheme.     

ScholOnto: an ontology-based digital library server for research documents and discourse

The internet is rapidly becoming the first place for researchers to publish documents, but at present they receive little support in searching, tracking, analysing or debating concepts in a literature from scholarly perspectives. This paper describes the design rationale and implementation of ScholOnto, an ontology-based digital library server to support scholarly interpretation and discourse. It enables researchers to describe and debate via a semantic network the contributions a document makes, and its relationship to the literature. The paper discusses the computational services that an ontology-based server supports, alternative user interfaces to support interaction with a large semantic network, usability issues associated with knowledge formalisation, new work practices that could emerge, and related work. Published online: 22 September 2000     

Constructing Geographic Digital Libraries using a Hypermedia Framework

This paper presents an object oriented hypermedia database framework for designing and building digital libraries, which are treated as enhanced hypermedia applications. It is based on combining and extending results from two domains: the navigation characteristics of hypertext systems, and the view mechanism and the persistent storage management facility of an object oriented database management system. As a result, users can alternate between two integrated types of interaction modes. The hypertext dimension of the framework allows navigation via static and dynamic hyperlinks; the object oriented database support enables querying by content and metadata management. The framework includes still a digital library design methodology that guides the implementation of digital libraries over the OODBMS. This proposal integrates hypermedia and DL concepts to a database environment, being instantiated on the realm of geographic data.     

数字信息管理自由报表的设计探析

通过利用先进的软件开发技术为用户提供了一个报表二次开发平台,以实现数字信息管理系统功能。该文拟从报表设计的基本格式入手,介绍了数字信息管理自由报表系统的结构,进一步阐述了数字信息管理自由报表系统的实现。     

Recognition Algorithms for Structured Documents with Variable Content

The paper deals with a wide class of structured documents that cannot be described using one or several models based on associations between the document fields and geometric elements. A formal model of such documents is described that is based on the concept of a multiset. Examples of structured documents of this class are given and a technique for the construction of models of structured documents is proposed. This technique is illustrated using an implementation of an automated document management system. Implemented algorithms for detecting document fields are described, and implementation problems are discussed.__________Translated from Programmirovanie, Vol. 31, No. 4, 2005.Original Russian Text Copyright © 2005 by Slavin.     

多版本XML文档的高效能索引机制的研究

首先对XML文档的编码方式作了改进,提出了用浮点数对插入子树进行编码的方法,新的编码方法能较好地支持XML文档的插入更新,在此基础上提出了支持多版本XML文档的新的索引机制,最后扩展了一个经典的结构化连接算法使之不仅能支持多版本XML文档的查询,而且还能较好地避免连接过程中的冗余操作.对XML的版本管理,尤其是在索引和查询优化方面提供了一些新的思路.     

基于数字校园的单一数据管理系统设计与实现

针对数字校园建设过程中存在的没有业务系统支持,但是又非常重要的孤立数据(单一数据),设计并实现了基于数字校园的单一数据管理系统,保障这些数据的及时性、准确性和可共享性。     

面向GJB 2725A-2001的评测过程管理平台

设计了一个针对GJB 2725A-2001的测评过程管理平台——QESuite2.0。总结了GJB 2725A-2001及附加文件中与测评过程管理相关概念及模型。在此基础上阐述了流程可裁剪、功能可拆卸、项目可定制、文档可自动生成的总体功能架构及基于该框架的设计思想。给出了系统实现中的技术要点并讨论了后续的研发工作及应用前景。