Computer Sciences Commons^™

Learning Real-Time A* Path Planner For Sensing Closely-Spaced Targets From An Aircraft, Jason K. Howlett, Michael A. Goodrich, Timothy W. Mclain

Faculty Publications

This work develops an any-time path planner, based on the learning real-time A* (LRTA*) search, for generating flyable paths that allow an aircraft with a specified sensor footprint to sense a group of closely-spaced targets. The LRTA* algorithm searches a tree of flyable paths for the branch that accomplishes the desired objectives in the shortest distance. The tree of paths is created by assembling primitive turn and straight sections of a specified step size. The operating parameters for the LRTA* search directly influence the running time and path-length performance of the search. A modified LRTA* search is presented that terminates …

Factors Influencing The Adoption Of E-Marketplaces By Small Organizations: An Empirical Investigation, Xin Tan, Fiona Fui-Hoon Nah, Charalambos Iacovou, Jaekyung. Kim

Research Collection School Of Computing and Information Systems

The emergence of mobile computing combined with the increased popularity of the Internet is changing our daily lives. The increasing use of small portable computers, wireless networks and satellites un folds the new technology of mobile computing, which allows transmis sion of data to computers that are not physically linked to a network. As a result, people can communicate on the move. Mobile devices with new input and output methods and form factors are dramatically different from traditional desktop computers (Rodden et al., 1998). These technological changes make increasing demands on both the quality of user interface and the functionality …

The Effect Of Domain Knowledge On Icon Visualization, Keng Siau, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

Iconic interfaces are now the de facto interface for most computer systems. Despite the popularity of iconic interfaces and the widespread belief that iconic interfaces are easier to comprehend than non-iconic interfaces, we have not come across any published study that has examined the effect of domain knowledge on end users’ interpretation of icons. An understanding of the relationship between domain knowledge and its effect on interpretation will enable us to design better icons to not only facilitate end users’ interpretation but also reduce misinterpretations of icons. This paper reports on an experimental study that investigates the effect of domain …

A Study On Tolerable Waiting Time: How Long Are Web Users Willing To Wait?, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

The WWW has become an important channel for information access, electronic commerce, and publication. With an exponential increase in the number of Web users and the popularity of multimedia technology, users often face a long waiting time for downloading Web pages. Although various technologies and techniques have been implemented to alleviate the situation and to comfort the impatient users, little research has been done to assess what constitutes an acceptable and tolerable waiting time for Web users. This research reviews the literature on computer response time and users’ waiting time, and assesses Web users’ tolerable waiting time in information retrieval. …

Performance Sensitivity And Fairness Of Ecn-Aware 'Modified Tcp', Archan Misra, Teunis Ott

Research Collection School Of Computing and Information Systems

The paper discusses how Explicit Congestion Notification (ECN) can be used to devise a congestion control mechanism for the Internet, which is more rapidly reactive and allows best-effort flows to rapidly adjust to fluctuations in available capacity. Our ECN-mod protocol involves simple modifications to TCP behavior and leverages more aggressive marking-based router feedback.Simulations show that ECN-mod is better than TCP NewReno even for Web-style intermittent traffic sources, and makes the link utilization significantly less sensitive to the variation in the number of active flows. Simulations also show that, while ECN-mod flows obtain a larger portion of the available capacity than …

Erp Implementation: Chief Information Officers’ Perceptions Of Critical Success Factors, Fiona Fui-Hoon Nah, Kathryn M. Zuckweiler, Janet Lee-Shang Lau

Research Collection School Of Computing and Information Systems

This article reports the results of a survey of Chief Information Officers (CIOs) from Fortune 1000 companies on their perceptions of the critical success factors in Enterprise Resource Planning (ERP) implementation. Through a review of the literature, 11 critical success factors were identified , with underlying subfactors, for successful ERP implementation. The degree of criticality of each of these factors were assessed in a survey administered to the CIOs. The 5 most critical factors identified by the CIOs were top management support, project champion, ERP teamwork and composition, project management, and change management program and culture. The importance of each …

Information Systems Requirements Determination And Analysis: A Mental Modeling Approach, Keng Siau, X. Tan

Research Collection School Of Computing and Information Systems

Regardless of the system development methodology adopted, being able to understand users’ informationrequirements is vital to the success of an information systems project. The intrinsic communications obstaclesexist within an individual user, among users, and between users and systems analysts. Different requirementsdetermination and analysis (RDA) techniques have been widely used with different outcomes. Some limitations of these techniques can be identified. In this paper, we propose a mental modeling approach to support RDA. Popular in other disciplines, mental modeling techniques have some distinct advantages to overcome some intrinsic communication obstacles in RDA, and to complement other techniques.

Pre-Conference Proceedings Of The Focus Symposium On Collaborative Decision-Support Systems, Collaborative Agent Design Research Center

Collaborative Agent Design (CAD) Research Center

The papers included in these pre-conference proceedings reflect the increasing focus on the utilization of computers as collaborating, decision-assistance partners in complex and often time-critical problem situations. There are high expectations that intelligent software agents will solve many of our current information system woes, such as lack of interoperability, multiple failure points, vulnerability to intrusion, making the right information available to the right person at the right time, and proposing solutions under time-critical conditions. Software agents do not have magical human-like capabilities. It is not possible to simply develop a piece of software code that is capable of reasoning about …

The Knowledge Level Approach To Intelligent Information System Design, Michael A. Zang, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Traditional approaches to building intelligent information systems employ an ontology to define a representational structure for the data and information of interest within the target domain of the system. At runtime, the ontology provides a constrained template for the creation of the individual objects and relationships that together define the state of the system at a given point in time. The ontology also provides a vocabulary for expressing domain knowledge typically in the form of rules (declarative knowledge) or methods (procedural knowledge). The system utilizes the encoded knowledge, often in conjunction user input, to progress the state of the system …

The Emerging Knowledge Management Paradigm: Some Organizational And Technical Issues, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

This paper addresses the expectations, organizational implications, and information processing requirements, of the emerging knowledge management paradigm. A brief discussion of the enablement of the individual through the wide-spread availability of computer and communication facilities, is followed by a description of the structural evolution of organizations, and the architecture of a computer-based knowledge management system. The author discusses two trends that are driven by the treatment of information and knowledge as a commodity: increased concern for the management and exploitation of knowledge within organizations; and, the creation of an organizational environment that facilitates the acquisition, sharing and application of knowledge. …

Using Caching For Browsing Anonymity, Anna M. Shubina, Sean W. Smith

Computer Science Technical Reports

Privacy-providing tools, including tools that provide anonymity, are gaining popularity in the modern world. Among the goals of their users is avoiding tracking and profiling. While some businesses are unhappy with the growth of privacy-enhancing technologies, others can use lack of information about their users to avoid unnecessary liability and even possible harassment by parties with contrary business interests, and to gain a competitive market edge. Currently, users interested in anonymous browsing have the choice only between single-hop proxies and the few more complex systems that are available. These still leave the user vulnerable to long-term intersection attacks. In this …

Tegrid: Demonstration Of A Semantic Web Environment, Steven Gollery, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Over the past several years there has been an increasing recognition of the shortcomings of message-passing data-processing systems that compute data without understanding, and the vastly superior potential capabilities of information-centric systems that incorporate an internal information model with sufficient context to support a useful level of automatic reasoning.

The key difference between a data-processing and an information-centric environment is the ability to embed in the information-centric software some understanding of the information being processed. The term information-centric refers to the representation of information in the computer, not to the way it is actually stored in a digital machine. This …

T-Splines And T-Nurccs, Thomas W. Sederberg, Jianmin Zheng, Almaz Bakenov, Ahmad Nasri

Faculty Publications

This paper presents a generalization of non-uniform B-spline surfaces called T-splines. T-spline control grids permit T-junctions, so lines of control points need not traverse the entire control grid. T-splines support many valuable operations within a consistent framework, such as local refinement, and the merging of several B-spline surfaces that have different knot vectors into a single gap-free model. The paper focuses on T-splines of degree three, which are C2 (in the absence of multiple knots). T-NURCCs (Non-Uniform Rational Catmull-Clark Surfaces with T-junctions) are a superset of both T-splines and Catmull-Clark surfaces. Thus, a modeling program for T-NURCCs can handle any …

Adaptive Live Video Streaming By Priority Drop, Jie Huang, Charles Krasic, Jonathan Walpole

Computer Science Faculty Publications and Presentations

In this paper we explore the use of Priority-progress streaming (PPS) for video surveillance applications. PPS is an adaptive streaming technique for the delivery of continuous media over variable bit-rate channels. It is based on the simple idea of reordering media components within a time window into priority order before transmission. The main concern when using PPS for live video streaming is the time delay introduced by reordering. In this paper we describe how PPS can be extended to support live streaming and show that the delay inherent in the approach can be tuned to satisfy a wide range of …

The Mistaken Axioms Of Wireless-Network Research, David Kotz, Calvin Newport, Chip Elliott

Computer Science Technical Reports

Most research on ad-hoc wireless networks makes simplifying assumptions about radio propagation. The ``Flat Earth'' model of the world is surprisingly popular: all radios have circular range, have perfect coverage in that range, and travel on a two-dimensional plane. CMU's ns-2 radio models are better but still fail to represent many aspects of realistic radio networks, including hills, obstacles, link asymmetries, and unpredictable fading. We briefly argue that key ``axioms'' of these types of propagation models lead to simulation results that do not adequately reflect real behavior of ad-hoc networks, and hence to network protocols that may not work well …

On The Intrinsic Complexity Of Learning Recursive Functions, Sanjay Jain, Efim Kinber, Christophe Papazian, Carl Smith, Rolf Wiehagen

School of Computer Science & Engineering Faculty Publications

The intrinsic complexity of learning compares the difficulty of learning classes of objects by using some reducibility notion. For several types of learning recursive functions, both natural complete classes are exhibited and necessary and sufficient conditions for completeness are derived. Informally, a class is complete iff both its topological structure is highly complex while its algorithmic structure is easy. Some self-describing classes turn out to be complete. Furthermore, the structure of the intrinsic complexity is shown to be much richer than the structure of the mind change complexity can behave “orthogonally”.

A Visual Framework Invites Human Into The Clustering Process, Keke Chen, Ling Liu

Kno.e.sis Publications

Clustering is a technique commonly used in scientific research. The task of clustering inevitably involves human participation - the clustering is not finished when the computer/algorithm finishes but the user has evaluated, understood and accepted the patterns. This defines a human involved "clustering-analysis/evaluation" iteration. Instead of neglecting this human involvement, we provide a visual framework (VISTA) with all power of algorithmic approaches (since their result can be visualized), and in addition we allow the user to steer/monitor/refine the clustering process with domain knowledge. The visual-rendering result also provides a precise pattern for fast post-processing.

Toward A Comprehensive Supplement For Language Courses, Krishnaprasad Thirunarayan, Stephen P. Carl

Kno.e.sis Publications

No abstract provided.

3d User Interface For A File Management System, Luiz Fernando Capretz, David Carter

Electrical and Computer Engineering Publications

Two-dimensional graphical user interface (GUI) is now firmly established as the preferred interface for most applications. The purpose of this work was to develop a three-dimensional user interface as a front end for a file management system and to evaluate the efficiency of a practical 3D application. In order to create this software, a previously defined 3D graphics engine, called Valve Software’s Half-Life, was extended to provide a directory traversal and the basic file management functions (cut, copy, paste, delete). The project was divided into two basic components: generating the 3D “world”, and altering the Half-Life engine to provide some …

A Closer Look At Boosted Image Retrieval, Nicholas Howe

Computer Science: Faculty Publications

Margin-maximizing techniques such as boosting have been generating excitement in machine learning circles for several years now. Although these techniques offer significant improvements over previous methods on classification tasks, little research has examined the application of techniques such as boosting to the problem of retrieval from image and video databases. This paper looks at boosting for image retrieval and classification, with a comparative evaluation of several top algorithms combined in two different ways with boosting. The results show that boosting improves retrieval precision and recall (as expected), but that variations in the way boosting is applied can significantly affect the …

A Generic Object-Oriented Tabu Search Framework, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Presently, most tabu search designers devise their applications without considering the potential of design and code reuse, which consequently prolong the development of subsequent applications. In this paper, we propose a software solution known as Tabu Search Framework (TSF), which is a generic C++ software framework for tabu search implementation. The framework excels in code recycling through the use of a welldesigned set of generic abstract classes that clearly define their collaborative roles in the algorithm. Additionally, the framework incorporates a centralized process and control mechanism that enhances the search with intelligence. This results in a generic framework that is …

Event Based Retrieval From Digital Libraries Containing Data Streams, Mohamed Hamed Kholief

Computer Science Theses & Dissertations

The objective of this research is to study the issues involved in building a digital library that contains data streams and allows event-based retrieval. “Digital Libraries are storehouses of information available through the Internet that provide ways to collect, store, and organize data and make it accessible for search, retrieval, and processing” [29]. Data streams are sources of information for applications such as news-on-demand, weather services, and scientific research, to name a few. A data stream is a sequence of data units produced over a period of time. Examples of data streams are video streams, audio stream, and sensor readings. …

Fast And Space-Efficient Location Of Heavy Or Dense Segments In Run-Length Encoded Sequences, Ronald I. Greenberg

Computer Science: Faculty Publications and Other Works

This paper considers several variations of an optimization problem with potential applications in such areas as biomolecular sequence analysis and image processing. Given a sequence of items, each with a weight and a length, the goal is to find a subsequence of consecutive items of optimal value, where value is either total weight or total weight divided by total length. There may also be a specified lower and/or upper bound on the acceptable length of subsequences. This paper shows that all the variations of the problem are solvable in linear time and space even with non-uniform item lengths and divisible …

Using Reconstructability Analysis To Select Input Variables For Artificial Neural Networks, Stephen Shervais, Martin Zwick

Complex Systems Faculty Publications and Presentations

We demonstrate the use of Reconstructability Analysis to reduce the number of input variables for a neural network. Using the heart disease dataset we reduce the number of independent variables from 13 to two, while providing results that are statistically indistinguishable from those of NNs using the full variable set. We also demonstrate that rule lookup tables obtained directly from the data for the RA models are almost as effective as NNs trained on model variables.

Level Compressed Dags For Lookup Tables, Ioannis Ioannidis, Ananth Y. Grama

Department of Computer Science Technical Reports

No abstract provided.

On Monitoring And Controlling Qos Network Domains, Ahsan Habib, Sonia Fahmy, Bharat Bhargava

Department of Computer Science Technical Reports

No abstract provided.

Record Linkage: A Machine Learning Approach, A Toolbox, And A Digital Government Web Service, Mohamed G. Elfeky, Vassilios S. Verykios, Ahmed K. Elmagarmid, Thanaa M. Ghanem, Ahmed R. Huwait

Department of Computer Science Technical Reports

No abstract provided.

Distributed Clustering For Scalable, Long-Lived Sensor Networks, Ossama Younis, Sonia Fahmy

Department of Computer Science Technical Reports

No abstract provided.

Violin: Virtual Internetworking On Overlay Infrastructure, Xuxian Jiang, Dongyan Xu

Department of Computer Science Technical Reports

No abstract provided.

Detection Of Documentary Scene Changes By Audio-Visual Fusion, Atulya Velivelli, Chong-Wah Ngo, Thomas S. Huang

Research Collection School Of Computing and Information Systems

The concept of a documentary scene was inferred from the audio-visual characteristics of certain documentary videos. It was observed that the amount of information from the visual component alone was not enough to convey a semantic context to most portions of these videos, but a joint observation of the visual component and the audio component conveyed a better semantic context. From the observations that we made on the video data, we generated an audio score and a visual score. We later generated a weighted audio-visual score within an interval and adaptively expanded or shrunk this interval until we found a …