Digital Commons Network^™

Enemy At The Gate: Threats To Information Security, Michael E. Whitman

Faculty Articles

A firm can build more effective security strategies by identifying and ranking the severity of potential threats to its IS efforts.

Haptic-Geozui3d: Exploring The Use Of Haptics In Auv Path Planning, Rick Komerska, Colin Ware

Center for Coastal and Ocean Mapping

We have developed a desktop virtual reality system that we call Haptic-GeoZui3D, which brings together 3D user interaction and visualization to provide a compelling environment for AUV path planning. A key component in our system is the PHANTOM haptic device (SensAble Technologies, Inc.), which affords a sense of touch and force feedback – haptics – to provide cues and constraints to guide the user’s interaction. This paper describes our system, and how we use haptics to significantly augment our ability to lay out a vehicle path. We show how our system works well for quickly defining simple waypoint-towaypoint (e.g. transit) …

Two-Dimensional Cubic Convolution, Stephen E. Reichenbach, Frank Geng

School of Computing: Faculty Publications

This paper develops two-dimensional (2-D), nonseparable, piecewise cubic convolution (PCC) for image interpolation. Traditionally, PCC has been implemented based on a one-dimensional (1-D) derivation with a separable generalization to two dimensions. However, typical scenes and imaging systems are not separable, so the traditional approach is suboptimal. We develop a closed-form derivation for a two-parameter, 2-D PCC kernel with support [-2, 2] [-2, 2] that is constrained for continuity, smoothness, symmetry, and flat-field response. Our analyses using several image models, including Markov random fields, demonstrate that the 2-D PCC yields small improvements in interpolation fidelity over the traditional, separable approach. The …

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 …

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.

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 …

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.

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.

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 …

Investigation Of Third Party Rights Service And Shibboleth Modification To Introduce The Service, Sanket Agrawal

Dartmouth College Master’s Theses

Shibboleth is an architecture to support inter-institutional sharing of electronic resources that are subject to access control. Codifying copyright in Shibboleth authorization policies is difficult because of the copyright exceptions which can be highly subjective. Third Party Rights Service is a high-level concept that has been suggested as a solution to approximate the exceptions of copyright law. In this thesis, I investigate the components of the Third Party Rights Service. I design and analyze a modified Shibboleth architecture based on these components. The resulting architecture allows for the phased addition of the resources to make use of the Third Party …

Multi-Chart Geometry Images, P. V. Sander, Z. J. Wood, S. J. Gortler, H. Hoppe

Computer Science and Software Engineering

We introduce multi-chart geometry images, a new representation for arbitrary surfaces. It is created by resampling a surface onto a regular 2D grid. Whereas the original scheme of Gu et al. maps the entire surface onto a single square, we use an atlas construction to map the surface piecewise onto charts of arbitrary shape. We demonstrate that this added flexibility reduces parametrization distortion and thus provides greater geometric fidelity, particularly for shapes with long extremities, high genus, or disconnected components. Traditional atlas constructions suffer from discontinuous reconstruction across chart boundaries, which in our context create unacceptable surface cracks. Our solution …

Transformation: The Human Obstacles, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

This paper addresses the human aspects of change at a time when the rapid wide-spread implementation of a new infostructure has become the cornerstone of national security policies. The author explores the behavioral characteristics of human beings from a point of view that is not based on inter-human comparisons, but on an examination of the innate physical, biological, intellectual, emotional, and social characteristics of our species. It is argued that the experience-based nature of the human cognitive system greatly reduces our ability to adapt to changes in our environment, exploit opportunities, and create new knowledge. A fundamental biological survival instinct …

A Self-Adapting Healthcare Information Infrastructure Using Mobile Computing Devices, James K. Archibald, Eric S. Hall, Charles D. Knutson, David K. Vawdrey

Faculty Publications

Despite recent improvements in the gathering and sharing of patient medical information among healthcare providers, there remains a gap in the electronic medical record infrastructure. Patient data is not available in some situations, either because the infrastructure is inaccessible (as in a natural disaster) or because there is no way to link the patient to the infrastructure (e.g., the patient cannot supply necessary identification information). This paper describes the Poket Doktor System, an architecture that allows an individual to carry personal electronic medical information on a wireless handheld device such as a smart card, cell phone, or PDA. Medical workers …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 19, Number 8, June 2003, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

802.11b Wireless Network Visualization And Radiowave Propagation Modeling, Chris Lentz

Dartmouth College Undergraduate Theses

This paper outlines the methods of creating detailed coverage maps of 802.11b networks, with an emphasis on minimizing the expenses and time involved. The goal of this work is to develop and present a streamlined, reproducible approach to wireless visualization as well as techniques for predicting coverage area before conducting network installations. After evaluating these coverage maps, a repeated series of field measurements will be checked against interpolated values in order to improve techniques for extrapolation of data for unsampled regions. If successful, these extrapolation techniques will provide additional guidelines for, and assist modeling of, new wireless network installations. However, …

An Evaluation Of The Impact Of Models For Radio Propagation On The Simulation Of 802.11b Wireless Networks, Evan W. Richardson

Dartmouth College Undergraduate Theses

Working with an existing wireless network simulator, we describe the addition of both a method for modeling arbitrary terrain, and for calculating signal attenuation with the Irregular Terrain Model (ITM). We also investigate ITM's effects on upper protocol layer in comparison to the Two-Ray Ground Reflection model. Upon examination, it was found that aside from the terrain between the transmitter and receiver, ITM's various parameters are of little significance in the computed signal attenuation. Further, examination of the behavior of the upper protocol layers revealed that at high traffic levels, choice of propagation model can have significant effects on the …

Power Conservation In The Network Stack Of Wireless Sensors, Michael De Rosa

Dartmouth College Undergraduate Theses

Wireless sensor networks have recently become an incredibly active research area in the networking community. Much attention has been given to the construction of power-conserving protocols and techniques, as battery life is the one factor that prevents successful wide-scale deployment of such networks. These techniques concentrate on the optimization of network behavior, as the wireless transmission of data is the most expensive operation performed by a sensor node. Very little work has been published on the integration of such techniques, and their suitability to various application domains. This paper presents an exhaustive power consumption analysis of network stacks constructed with …

Enhancing Asynchronous Parallel Computing, Elizabeth Anne Hamon

Dartmouth College Undergraduate Theses

In applications using large amounts of data, hiding the latency inherent in accessing data far from the processor is often necessary in order to achieve high performance. Several researchers have observed that one way to address the challenge of latency is by using a common structure: in a series of passes, the program reads in the data, performs various operations on it, and writes out the data. Passes often consist of a pipeline structure composed of different stages. In order to achieve high performance, the stages are frequently overlapped, for example, by using asynchronous threads. Out-of-core parallel programs provide one …

A Surface-Based Approach For Classification Of 3d Neuroanatomic Structures, Li Shen, James Ford, Fillia Makedon, Andrew Saykin

Computer Science Technical Reports

We present a new framework for 3D surface object classification that combines a powerful shape description method with suitable pattern classification techniques. Spherical harmonic parameterization and normalization techniques are used to describe a surface shape and derive a dual high dimensional landmark representation. A point distribution model is applied to reduce the dimensionality. Fisher's linear discriminants and support vector machines are used for classification. Several feature selection schemes are proposed for learning better classifiers. After showing the effectiveness of this framework using simulated shape data, we apply it to real hippocampal data in schizophrenia and perform extensive experimental studies by …

Flow And Pressure Distributions In Vascular Networks Consisting Of Distensible Vessels, Gary S. Krenz, Christopher A. Dawson

Mathematics, Statistics and Computer Science Faculty Research and Publications

We examine the influence of vessel distensibility on the fraction of the total network flow passing through each vessel of a model vascular network. An exact computational methodology is developed yielding an analytic proof. For a class of structurally heterogeneous asymmetric vascular networks, if all the individual vessels share a common distensibility relation when the total network flow is changed, this methodology proves that each vessel will continue to receive the same fraction of the total network flow. This constant flow partitioning occurs despite a redistribution of pressures, which may result in a decrease in the diameter of one and …

Adding Semantics To Web Services Standards, Kaarthik Sivashanmugam, Kunal Verma, Amit P. Sheth, John Miller

Kno.e.sis Publications

With the increasing growth in popularity of Web services, discovery of relevant Web services becomes a significant challenge. One approach is to develop semantic Web services where by the Web services are annotated based on shared ontologies, and use these annotations for semantics-based discovery of relevant Web services. We discuss one such approach that involves adding semantics to WSDL using DAML+OIL ontologies. Our approach also uses UDDI to store these semantic annotations and search for Web services based on them. We compare our approach with another initiative to add semantics to support Web service discovery, and show how our approach …

Towards Cost-Effective On-Demand Continuous Media Service: A Peer-To- Peer Approach, Yicheng Tu, Shan Lei

Department of Computer Science Technical Reports

No abstract provided.

Recovery Performance Of Pgm With Redundancy Estimation For Proactive Fec, Sonia Fahmy, Renin M. Jegadeesan

Department of Computer Science Technical Reports

No abstract provided.

Vulnerabilities And Safe-Guards In Networks With Qos Support, Sonia Fahmy, Srinivas R. Avasarala, Venkatesh Prabhakar

Department of Computer Science Technical Reports

No abstract provided.

Ladar-Based Detection And Tracking Of Moving Objects From A Ground Vehicle At High Speeds, Chieh-Chih Wang, Charles Thorpe, Arne Suppe

Research Collection School Of Computing and Information Systems

Detection and tracking of moving objects (DATMO) in crowded urban areas from a ground vehicle at high speeds is difficult because of a wide variety of targets and uncertain pose estimation from odometry and GPS/DGPS. In this paper we present a solution of the simultaneous localization and mapping (SLAM) with DATMO problem to accomplish this task using ladar sensors and odometry. With a precise pose estimate and a surrounding map from SLAM, moving objects are detected without a priori knowledge of the targets. The interacting multiple model (IMM) estimation algorithm is used for modeling the motion of a moving object …

Adaptive Filters For Continuous Queries Over Distributed Data Stream, Chris Olston, Jing Jiang, Jennifer Widom

Research Collection School Of Computing and Information Systems

We consider an environment where distributed data sources continuously stream updates to a centralized processor that monitors continuous queries over the distributed data. Significant communication overhead is incurred in the presence of rapid update streams, and we propose a new technique for reducing the overhead. Users register continuous queries with precision requirements at the central stream processor, which installs filters at remote data sources. The filters adapt to changing conditions to minimize stream rates while guaranteeing that all continuous queries still receive the updates necessary to provide answers of adequate precision at all times. Our approach enables applications to trade …

A New Message-Based Protocol For Building A Platform And Language Independent Distributed Object Model, Hazem S. El Ashmawi

Archived Theses and Dissertations

Standardization of messaging topologies for communication in recent distributed object computing architectures is becoming more and more inevitable. The emergence of a structured and flexible document model as XML has made an entry point towards this goal. In this thesis, we are utilizing the flexibility of XML and the simplicity of low -level socket communication to build a generalized messaging model that provides a basis for standardization and supports interoperability among existing distributed object computing architectures. The proposed system is composed of the basic components of a distributed architecture constituting a number of broker components acting as naming services and …

Image Morphological Processing, Vijayalakshmi Gaddipati

Dissertations

Mathematical Morphology with applications in image processing and analysis has been becoming increasingly important in today's technology. Mathematical Morphological operations, which are based on set theory, can extract object features by suitably shaped structuring elements. Mathematical Morphological filters are combinations of morphological operations that transform an image into a quantitative description of its geometrical structure based on structuring elements. Important applications of morphological operations are shape description, shape recognition, nonlinear filtering, industrial parts inspection, and medical image processing.

In this dissertation, basic morphological operations, properties and fuzzy morphology are reviewed. Existing techniques for solving corner and edge detection are presented. …

Image Enhancement Techniques Applied To Solar Feature Detection, Artur J. Kowalski

Dissertations

This dissertation presents the development of automatic image enhancement techniques for solar feature detection. The new method allows for detection and tracking of the evolution of filaments in solar images. Series of H-alpha full-disk images are taken in regular time intervals to observe the changes of the solar disk features. In each picture, the solar chromosphere filaments are identified for further evolution examination. The initial preprocessing step involves local thresholding to convert grayscale images into black-and-white pictures with chromosphere granularity enhanced. An alternative preprocessing method, based on image normalization and global thresholding is presented. The next step employs morphological closing …