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An OAI-based Digital Library Framework for Biodiversity Information Systems
Get PDFBiodiversity information systems (BISs) involve all kinds of heterogeneous data, which include ecological and geographical features. However, available information systems offer very limited support for managing such data in an integrated fashion, and integration is often based on geographic coordinates alone. Furthermore, such systems do not fully support image content management (e.g., photos of landscapes or living organisms), a requirement of many BIS end-users. In order to meet their needs, these users - e.g., biologists, environmental experts - often have to alternate between distinct biodiversity and image information systems to combine information extracted from them. This cumbersome operational procedure is forced on users by lack of interoperability among these systems. This hampers the addition of new data sources, as well as cooperation among scientists. The approach provided in this paper to meet these issues is based on taking advantage of advances in Digital Library (DL) innovations to integrate networked collections of heterogeneous data. It focuses on creating the basis for a biodiversity information system under the digital library perspective, combining new techniques of content-based image retrieval and database query processing mechanisms. This approach solves the problem of system switching, and provides users with a flexible platform from which to tailor a BIS to their needs
Interfaces for Cloning in Immersive Virtual Environments
Get PDFThree-dimensional objects in many application domains, such as architecture and construction, can be extremely complex and can consist of a large number of components. However, many of these complex objects also contain a great deal of repetition. Therefore, cloning techniques, which generate multiple spatially distributed copies of an object to form a repeated pattern, can be used to model these objects more efficiently. Such techniques are important and useful in desktop three-dimensional modeling systems, but we are not aware of any cloning techniques designed for immersive virtual environments (VEs). In this paper, we present an initial effort toward the design and development of such interfaces. We define the design space of the cloning task, and present five novel VE interfaces for cloning, then articulate the design rationale. We have also performed a usability study intended to elicit subjective responses with regard to affordance, feedback, attention, perceived usefulness, ease of use, and ease of learning in these interfaces. The study resulted in four major conclusions. First, slider widgets are better suited for discrete than for continuous numeric input. Second, the attentional requirements of the interface increase with increased degrees-of-freedom associated with widgets. Third, users prefer constrained widget movement, although more degrees-of-freedom allow more efficient parameter setting. Finally, appropriate feedback can reduce the cognitive load. The lessons we learned will influence our continuing design of cloning techniques, and these techniques will ultimately be applied to VE applications for design, construction, and prototyping
Intelligent Fusion of Structural and Citation-Based Evidence for Text Classification
Get PDFThis paper investigates how citation-based information and structural content (e.g., title, abstract) can be combined to improve classification of text documents into predefined categories. We evaluate different measures of similarity, five derived from the citation structure of the collection, and three measures derived from the structural content, and determine how they can be fused to improve classification effectiveness. To discover the best fusion framework, we apply Genetic Programming (GP) techniques. Our empirical experiments using documents from the ACM digital library and the ACM classification scheme show that we can discover similarity functions that work better than any evidence in isolation and whose combined performance through a simple majority voting is comparable to that of Support Vector Machine classifiers
Designing for Seamless Task Migration in MPUIs: Bridging Task-Disconnects
Get PDFToday, the proliferation of mobile computing has changed the work environment forever. As a consequence, users are forced to orchestrate a complex interaction between multiple devices, moving data and information back and forth, to accomplish their tasks. Users trudge out USB key drives, remote desktop software, e-mail and network file storage in an attempt to mitigate this orchestration. We refer to this break from the task at hand as task-disconnect. Task-disconnect represents the break in continuity that occurs when a user attempts to accomplish his or her tasks using more than one device. Our objective is to study how software can bridge this task-disconnect, enabling users to seamlessly transition their tasks among their devices. We present the theory, definition, and discussion of task-disconnect; our approach towards bridging this disconnect; and our prototype application that was built to be used across the desktop computer and the Tablet PC platforms. We then describe our subjective evaluation to measure the effectiveness of the prototype in bridging the task-disconnect. We then conclude with the results and insights gained from our evaluation
ODRPACK95: A Weighted Orthogonal Distance Regression Code with Bound Constraints
Get PDFODRPACK (TOMS Algorithm 676) has provided a complete package for weighted orthogonal distance regression for many years. The code is complete with user selectable reporting facilities, numerical and analytic derivatives, derivative checking, and many more features. The foundation for the algorithm is a stable and efficient trust region Levenberg-Marquardt minimizer that exploits the structure of the orthogonal distance regression problem. ODRPACK95 is a modification of the original ODRPACK code that adds support for bound constraints, uses the newer Fortran 95 language, and simplifies the interface to the user called subroutine
Designing Explicit Numeric Input Interfaces for Immersive Virtual Environments
Get PDFUser interfaces involving explicit control of numeric values in immersive virtual environments have not been well studied. In the context of designing three-dimensional interaction techniques for the creation of multiple objects, called cloning, we have developed and tested a dynamic slider interface (D-Slider) and a virtual numeric keypad (VKey). Our cloning interface requires precise number input because it allows users to place objects at any location in the environment with a precision of 1/10 unit. The design of the interface focuses on feedback, constraints, and expressiveness. Comparative usability studies have shown that the newly designed user interfaces were easy to use, effective, and had a good quality of interaction. We describe a working prototype of our cloning interface, the iterative design process for D-Slider and V-Key, and lessons learned. Our interfaces can be re-used for any virtual environment interaction tasks requiring explicit numeric input
General Interface Description of Websites using CLICK and UIML
Get PDFThis paper explores the domain of programming paradigm for Multi-Platform User Interfaces using XML based languages. The main focus of this work is User Interface Markup Language (UIML), an XML based language for describing user interfaces in a platform-independent manner. We have explored the capabilities of UIML as an interface description language for describing interactive websites. We have selected an end-user web programming tool called CLICK, which also uses an XML based interface description for the websites created through it. We have analyzed both the representations and devised a conversion process from CLICK XML to UIML. We have found that UIML is expressive enough to represent applications built using CLICK. UIML provides various benefits over the interface description generated by CLICK especially that of facilitating the development of web based interfaces for multiple platforms through CLICK
POLSYS GLP: A Parallel General Linear Product Homotopy Code for Solving Polynomial Systems of Equations
Get PDFGlobally convergent, probability-one homotopy methods have proven to be very effective for finding all the isolated solutions to polynomial systems of equations. After many years of development, homotopy path trackers based on probability-one homotopy methods are reliable and fast. Now, theoretical advances reducing the number of homotopy paths that must be tracked, and in the handling of singular solutions, have made probability-one homotopy methods even more practical. POLSYS GLP consists of Fortran 95 modules for nding all isolated solutions of a complex coefficient polynomial system of equations. The package is intended to be used on a distributed memory multiprocessor in conjunction with HOMPACK90 (Algorithm 777), and makes extensive use of Fortran 95 derived data types and MPI to support a general linear product (GLP) polynomial system structure. GLP structure is intermediate between the partitioned linear product structure used by POLSYS PLP (Algorithm 801) and the BKK-based structure used by PHCPACK. The code requires a GLP structure as input, and although nding the optimal GLP structure is a dicult combinatorial problem, generally physical or engineering intuition about a problem yields a very good GLP structure. POLSYS GLP employs a sophisticated power series end game for handling singular solutions, and provides support for problem denition both at a high level and via hand-crafted code. Dierent GLP structures and their corresponding Bezout numbers can be systematically explored before committing to root finding
SimFusion: A Unified Similarity Measurement Algorithm for Multi-Type Interrelated Web Objects
Get PDFIn this paper, we use a Unified Relationship Matrix (URM) to represent a set of heterogeneous web objects (e.g., web pages, queries) and their interrelationships (e.g., hyperlink, user click-through relationships). We claim that iterative computations over the URM can help overcome the data sparseness problem (a common situation in the Web) and detect latent relationships among heterogeneous web objects, thus, can improve the quality of various information applications that require the combination of information from heterogeneous sources. To support our claim, we further propose a unified similarity-calculating algorithm, the SimFusion algorithm. By iteratively computing over the URM, the SimFusion algorithm can effectively integrate relationships from heterogeneous sources when measuring the similarity of two web objects. Experiments based on a real search engine query log and a large real web page collection demonstrate that the SimFusion algorithm can significantly improve similarity measurement of web objects over both traditional content based similarity-calculating algorithms and the cutting edge SimRank algorithm
A Critique of Design Approaches for Notification Systems
Get PDFThe Fall 2004 Virginia Tech Undergraduate Research in Computer Science (VTURCS) class, taught by Dr. McCrickard, covered the following topics: problem, activity and information/interaction phases of design; scenario based design; interruption, reaction, and comprehension (IRC) values; stages of action; ubiquitous computing evaluation areas (UEAs) and participatory negotiation. This critique is my assessment and observations of how these design approaches worked for our project