By Topic

Digital Libraries, 1996. ADL '96., Proceedings of the Third Forum on Research and Technology Advances in

Date 13-15 May 1996

Filter Results

Displaying Results 1 - 16 of 16
  • Proceedings of ADL '96 Forum. Forum on Research and Technology Advances in Digital Libraries

    Save to Project icon | Request Permissions | PDF file iconPDF (246 KB)  
    Freely Available from IEEE
  • Author index

    Save to Project icon | Request Permissions | PDF file iconPDF (44 KB)  
    Freely Available from IEEE
  • The Iowa Health Book: creating, organizing and distributing a digital medical library of multimedia consumer health information on the Internet to improve rural health care by increasing rural patient access to information

    Page(s): 28 - 34
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (624 KB)  

    Patients need access to consumer health information in order to improve their health and well-being. Rural patients, by nature of their geographic location, have limited access to such information. A partnership has been formed between non-profit public health organizations, a health sciences library, a tertiary care medical center, a medical informatics laboratory, a state library system, and the citizens of Iowa. The purpose of the partnership is to create, organize and distribute a digital medical library of multimedia consumer health information on the Internet in order to improve rural patient access to consumer health information View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Target testing and the PicHunter Bayesian multimedia retrieval system

    Page(s): 66 - 75
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1092 KB)  

    We address how the effectiveness of a content-based, multimedia information retrieval system can be measured, and how such a system should best use response feedback in performing searches. We propose a simple, quantifiable measure of an image retrieval system's effectiveness, “target testing”, in which effectiveness is measured as the average number of images that a user must examine in searching for a given random target. We describe an initial version of PicHunter, a retrieval system designed to test a novel approach to relevance-feedback. This approach is based on a Bayesian framework that incorporates an explicit model of the user's selection process. PicHunter is intentionally designed to have a minimal, “queryless” user interface, so that its performance reflects only the performance of the relevance feedback algorithm. The algorithm, however, can easily be incorporated into more traditional, query-based systems. Employing no explicit query, and only a small amount of image processing, PicHunter is able to locate randomly selected targets in a database of 4522 images after displaying an average of only 55 groups of 4 images. This is more than 10 times better than random chance View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Robust retrieval of noisy text

    Page(s): 76 - 85
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (772 KB)  

    We examine the effects of simulated OCR errors on Boolean query models for information retrieval. We show that even relatively small amounts of such noise can have a significant impact. To address this issue, we formulate new variants of the traditional models by combining two classic paradigms for dealing with imprecise data: approximate string matching and fuzzy logic. Using a recall/precision analysis of an experiment involving nearly 60 million query evaluations, we demonstrate that the new fuzzy retrieval methods are generally more robust than their “sharp” counterparts View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • GeoChange: an experiment in wide-area database services for geographic information exchange

    Page(s): 14 - 23
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (952 KB)  

    The GeoChange project is investigating a distributed database management architecture and services to facilitate the perusal, selection, and retrieval of multiple, third-party geographic information sources (GIS) across wide area networks, such as the Internet. The system uses a quasi-dynamic approach to information exchange which combines loose coupling of the source systems with distributed database management support services to improve the speed and reliability of retrieval. Application developers can use the system for ad-hoc merging of information from diverse GIS sources. Filters and integrity constraints managed as metadata bring further efficiency to the information exchange process. This paper is an introduction to the GeoChange system architecture and its operation. A protoype implementation using real geographic databases provided by the Hong Kong GIS community is near completion View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Image Engine HPCC project. A medical digital library system using agent-based technology to create an integrated view of the electronic medical record

    Page(s): 45 - 56
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1576 KB)  

    This paper describes the Image Engine project supported by the National Library of Medicine's (NLM) biomedical applications of High Performance Computing and Communications (BAA/HPCC) program. Image Engine is a multi-user, object-oriented, client server database system for the storage, retrieval, integration and sharing of a wide range of biomedical images. In addition, Image Engine uses agent-based technology to implement real-time links between medical images and associated data stored in external database systems. This project is a first step towards implementing a multimedia electronic medical record system. As a digital library architecture Image Engine has the potential to support innovative applications in the clinical, research and educational domains of medicine View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • SemaLink: an approach for semantic browsing through large distributed document spaces

    Page(s): 86 - 94
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (696 KB)  

    Hypermedia retrieval in combination with querying is a very powerful document access metaphor for digital library systems. Conventional distributed hypermedia systems, however, suffer from some well-known problems that make effective, goal-directed document retrieval and maintenance impossible. On the one hand, relationships between documents are modeled on a very low level of abstraction, preventing knowledge re-use and user-adapted navigation through the document space. On the other hand, huge static web structures are prone to redundancies, inconsistencies and costly to maintain. We present an approach of a scalable distributed resource discovery and delivery system that offers access to information through querying and knowledge-based hypermedia browsing. Relationship knowledge is partitioned into handy, independent structures, modeled on a high level of abstraction apart from documents. Navigation paths are computed by the system, combining semantic networks with information retrieval View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • High speed satellite access to biomedical text/image databases

    Page(s): 35 - 44
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1156 KB)  

    This paper describes a satellite-mediated experiment in accessing biomedical databases. The experimental tool is MIRS, a prototype client/server, SQL-based system for the retrieval and display of medical information from mixed text/image databases. We have installed the MIRS client at the Laboratory for Radiological Informatics at the University of California at San Francisco and the MIRS server in our Image Processing Laboratory at the National Library of Medicine (NLM). We have run the MIRS client to do database queries and access images over a T-1 satellite link. Our initial performance evaluation has yielded results which relate to the ability of client/server systems such as MIRS to perform effectively over geosynchronous satellite links. We have developed an application-level method that allows for the efficient use of the standard TCP protocol. We have evaluated this method on the T-1 link provided by the NASA geosynchronous ACTS, and measured faster delivery of cervical spine x-ray images by a factor of 2.7:1, as compared to conventional FTP View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Digital libraries meet electronic commerce: on-screen intellectual property

    Page(s): 58 - 64
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (800 KB)  

    Publishers wishing to distribute text online fear that customers will download their product and redistribute it illegally. Although constraining the users to access the data only through proprietary software that does not allow downloading helps, it still leaves the possibility that users could take screen dumps of the material to capture it. The technique described in the paper relies on the perceptual properties of the human eye, using two unreadable images interleaved quickly to create a readable image, which cannot be screen-dumped since the readability depends on averaging in the human eye. Our program flickers two images of the text each with an admixture of grey noise. Your eye sorts out the letters and reads them, not paying close attention to the grey background; but any screen dump captures the item at one instant including the noise. The text is also scrolled up and down slowly, which again your eye can track, but which would frustrate a program trying to average out the flickering View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Scalability issues for high performance digital libraries on the World Wide Web

    Page(s): 139 - 148
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (980 KB)  

    We investigate scalability issues involved in developing high performance digital library systems. Our observations and solutions are based on our experience with the Alexandria Digital Library (ADL) testbed under development at UCSB. The current ADL system provides online browsing and processing of digitized maps and other geospatially mapped data via the World Wide Web (WWW). A primary activity of the ADL system involves computation and disk I/O for accessing compressed multi resolution images with hierarchical data structures, as well as other duties such as supporting database queries and on the fly HTML page generation. Providing multi resolution image browsing services can reduce network traffic but impose some additional cost at the server. We discuss the necessity of having a multiprocessor DL server to match potentially huge demands in simultaneous access requests from the Internet. We have developed a distributed scheduling system for processing DL requests, which actively monitors the usages of CPU, I/O channels and the interconnection network to effectively distribute work across processing units to exploit task and I/O parallelism. We present an experimental study on the performance of our scheme in addressing the scalability issues arising in ADL wavelet processing and file retrieval. Our results indicate that the system delivers good performance on these types of tasks View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An agent-based hypermedia framework for designing and developing digital libraries

    Page(s): 5 - 13
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (752 KB)  

    The idea of a digital library has many facets; and as such, is the focus for a number of emerging areas of study. We consider digital libraries as heterogeneous and dynamic information environments, and to that end, have identified inter-operability and extensibility as essential characteristics for effective digital libraries. We present what may be termed a “computer science” approach, through the development of an agent-based hypermedia model for digital libraries. Our model provides an agent-based framework which allows digital libraries to be considered, designed and developed as information environments being composed of different cooperating agents playing several roles: library agents providing information retrieval services; accessor agents providing information storage services; authors publishing their work; and finally users requesting information View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Authorization in the digital library: secure access to services across enterprise boundaries

    Page(s): 110 - 119
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (956 KB)  

    In large scale networked information systems (e.g. the World Wide Web), the community of subjects who may make requests to a service provider such as a digital library will often extend beyond the local community to include individuals about whom little prior knowledge, if any, exists at the provider. This poses challenges for resource protection which do not resist in traditional computing environments. The paper presents a formal framework for secure access to information and services in such systems, where both the size of the user base and a variety of local enterprise dependent representations of user attributes must be considered. In our framework, an individual supplies digital credentials akin to traditional paper credentials with a request for service. To decide whether to grant the request, the recipient interprets the credentials using knowledge about the credential issuers (more precisely, of what conditions must hold for the issuers to have issued the credentials) rather than, or in addition to, specific knowledge about the requester. Our formalism for access control also provides a basis for security oriented smart yellow pages facilities, which are directory services that manage queryable registries of information about service providers and their requirements View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Data compression using encrypted text

    Page(s): 130 - 138
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (636 KB)  

    We present an algorithm for text compression. The basic idea of our algorithm is to define a unique encryption or signature of each word in the dictionary by replacing certain characters in the words by a special character “*” and retaining a few characters so that the word is still retrievable. For any encrypted text the most frequently used character is “*” and the standard compression algorithms can exploit this redundancy in an effective way. We advocate the following compression paradigm: given a compression algorithm A and a text T, we apply the same algorithm A on an encrypted text *T and retrieve the original text via a dictionary which maps the decompressed text *T to the original text T. We report better results for most widely used compression algorithms such as Huffman, LZW, arithmetic, unix compress, gnu-zip with respect to a text corpus. The compression rates using these algorithms are much better than the dictionary based methods reported in the literature. One basic assumption of our algorithm is that the system has access to a dictionary of words used in all the texts along with a corresponding “cryptic” dictionary. The cost of this dictionary is amortized over the compression savings for all the text files handled by the organization. If two organizations wish to exchange information using our compression algorithm, they must share a common dictionary. We compare our methods with other dictionary based methods and present future research problems View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Query previews in networked information systems

    Page(s): 120 - 129
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1084 KB)  

    In a networked information system (such as the NASA Earth Observing System-Data Information System (EOS-DIS)), there are three major obstacles facing users in a querying process: network performance, data volume and data complexity. In order to overcome these obstacles, we propose a two phase approach to query formulation. The two phases are the Query Preview and the Query Refinement. In the Query Preview phase, users formulate an initial query by selecting rough attribute values. The estimated number of matching data sets is shown, graphically on preview bars which allows users to rapidly focus on a manageable number of relevant data sets. Query previews also prevent wasted steps by eliminating zero hit queries. When the estimated number of data sets is long enough, the initial query is submitted to the network which returns the metadata of the data sets for further refinement in the Query Refinement phase. The two phase approach to query formulation overcomes slow network performance, and reduces the data volume and data complexity, problems. This approach is especially appropriate for users who do not have extensive knowledge about the data and who prefer an exploratory method to discover data patterns and exceptions. Using this approach, we have developed dynamic query user interfaces to allow users to formulate their queries across a networked environment View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A digital library system for periodicals distribution

    Page(s): 95 - 103
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (704 KB)  

    As part of IBM's Digital Library Initiative, IBM's Almaden Research Center has teamed with the Institute for Scientific Information in a joint project to deliver on-line access to the bibliographic information and abstracts from the scientific journal articles indexed in Current Contents/Life Sciences as well as articles offered by the respective publishers. This requires both adaptation of existing technologies and development of new capabilities, especially regarding copyright protection. Since the Fall of 1995, a pilot system has been installed at four universities, two corporate libraries, and a major public research library, beginning a study that involves many publishers, libraries, and users to test the system and to experiment with new economic models. This article describes some requirements we identified for this system, and the solutions we have devised for these requirements View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.