Digital Commons Network^™

Firewall Or Folly - An Initial Investigation Into The Effectiveness Of Personal Firewalls In Securing Personal Computers From Attack, Jeshua Yee

Research outputs pre 2011

With the increase in the use of Personal Computer (PC) firewall, this study looks at the security features provided by eight PC firewall; they are BlackICE, Deerfield, Kirio, MacAfee, Outpost, Sygate, Tiny and Zonealarm. The Nessus network scanner was used to probe these systems in a variety of configurations. The paper discusses the results and their implications for users of this new range of software.

Studying The Functional Genomics Of Stress Responses In Loblolly Pine With The Expresso Microarray Experiment Management System, Lenwood S. Heath, Naren Ramakrishnan, Ronald R. Sederoff, Ross W. Whetten, Boris I. Chevone, Craig Struble, Vincent Y. Jouenne, Dawei Chen, Leonel Van Zyl, Ruth Grene

Mathematics, Statistics and Computer Science Faculty Research and Publications

Conception, design, and implementation of cDNA microarray experiments present a variety of bioinformatics challenges for biologists and computational scientists. The multiple stages of data acquisition and analysis have motivated the design of Expresso, a system for microarray experiment management. Salient aspects of Expresso include support for clone replication and randomized placement; automatic gridding, extraction of expression data from each spot, and quality monitoring; flexible methods of combining data from individual spots into information about clones and functional categories; and the use of inductive logic programming for higher-level data analysis and mining. The development of Expresso is occurring in parallel with …

Vertex-Unfoldings Of Simplicial Manifolds, Erik D. Demaine, David Eppstein, Jeff Erickson, George W. Hart, Joseph O'Rourke

Computer Science: Faculty Publications

We present an algorithm to unfold any triangulated 2-manifold (in particular, any simplicial polyhedron) into a non-overlapping, connected planar layout in linear time. The manifold is cut only along its edges. The resulting layout is connected, but it may have a disconnected interior; the triangles are connected at vertices, but not necessarily joined along edges. We extend our algorithm to establish a similar result for simplicial manifolds of arbitrary dimension.

Terra Incognita, Leslie Hill

Reconstruction: Studies in Contemporary Culture

No abstract provided.

In-Memory Evaluation Of Continuous Range Queries On Moving Objects, Dmitri V. Kalashnikov, Sunil Prabhakar

Department of Computer Science Technical Reports

No abstract provided.

Redesign Of A Spatial Gear Pair Using Configuration Spaces, Elisha Sacks, Leo Joskowicz, Ralf Schulthesis, Uwe Hinze

Department of Computer Science Technical Reports

No abstract provided.

Nonlinear Kinematic Tolerance Analysis Of Planar Mechanical Systems, Min-Ho Kyung, Elisha Sacks

Department of Computer Science Technical Reports

No abstract provided.

Kinematic Analysis Of Spatial Fixed-Axis Higher Pairs Using Configuration Spaces, Ku-Jin Kim, Elisha P. Sacks, Leo Joskowicz

Department of Computer Science Technical Reports

No abstract provided.

The Evolution Of Cell Colonies In Volvocacean Algae : Investigation By Theoretical Analysis And Computer Simulation., Frank Noe

Theses

This thesis presents a mathematical analysis and computational simulation which is used to investigate the evolution of cell colonies. The evolutionary transition from unicellular to cell colony form is a prerequesite for multicellular life as it exists abundantly on earth. This transition has occured numerous times independently so that we expect a high selective advantage to be associated with it. The photosynthetic green algae order Volvocaceae is an appropriate set of model organisms for the study of the evolution of cell colonies since it comprises living unicellular organisms, cell colonies, and multicellular organisms of different shapes, sizes and levels of …

An Investigation Into The Concepts And Applicability Of Agent Technologies, Anne White

Theses

The software world is one of great richness and diversity

Even though the concept of software agents date back to the days of AI (Artificial Intelligence) work (1970’s) the word “Agent” is currently in vogue in the computing press and computer science communities.

This thesis presents a review of the ongoing evolution of software agents, places agents in context within today’s software domain, and takes a closer look at the ongoing debate of what really constitutes an '"Agenf\ The numerous dimensions of classification are studied and an opinion of the attributes that an agent should encompass is put forward. Leading …

Design And Analysis Of Radio Frequency Deployment Algorithms For Gsm, Mónica Pérez-Carbonell

Theses

Due to the growth of the subscriber base and the introduction of new services, mobile communications networks’ demand for wireless resources is increasing. This has resulted in an increasing need to change the frequency allocation of a network in order to adapt the cellular network to new frequency demands.

Currently, a planning tool generates a new frequency plan, which is. then deployed to cell sites. The deployment should ideally be carried out with minimum disruption to network operation, which makes this deployment process a critical undertaking as any errors during or after the deployment can leave the network with poor …

Topological Sweep In Degenerate Cases, Eynat Rafalin, Diane Souvaine, Ileana Streinu

Computer Science: Faculty Publications

Topological sweep can contribute to efficient implementations of various algorithms for data analysis. Real data, however, has degeneracies. The modification of the topological sweep algorithm presented here handles degenerate cases such as parallel or multiply concurrent lines without requiring numerical perturbations to achieve general position. Our method maintains the 0(n2) and 0(n) time and space complexities of the original algorithm, and is robust and easy to implement. We present experimental results.

Interlocked Open Linkages With Few Joints, Erik D. Demaine, Stefan Langerman, Joseph O'Rourke, Jack Snoeyink

Computer Science: Faculty Publications

We advance the study of collections of open linkages in 3-space that may be interlocked in the sense that the linkages cannot be separated without one bar crossing through another. We consider chains of bars connected with rigid joints, revolute joints, or universal joints and explore the smallest number of chains and bars needed to achieve interlock. Whereas previous work used topological invariants that applied to single or to closed chains, this work relies on geometric invariants and concentrates on open chains.

Automated Ontology Learning For A Semantic Web, Christopher N. Hammack, Qingfeng Lin, Hai Huang, Stephen Scott, Sharad C. Seth

School of Computing: Technical Reports

By expressing web page content in a format that machines can understand, the semantic web provides huge possibilities for the Internet and for machine reasoning. Unfortunately, there is a considerable distance between the present-day World Wide Web and the semantic web of the future. The process of annotating the Web to make it semantic web-ready is quite long and not without resistance. In this paper one mechanism for semanticizing the Web is presented. This system is known as AutoSHOE, and it is capable of categorizing pages according to one of the present HTML semantic representations (Simple HTML Ontology Extensions) by …

Centralized Vs. Distributed Connection Management Schemes Under Different Traffic Patterns In Wavelength-Convertible Optical Networks, Lu Shen, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

Centralized and Distributed methods are two connection management schemes in wavelength convertible optical networks. In the earlier work, the centralized scheme is said to have lower network blocking probability than the distributed one. Hence, much of the previous work in connection management has focused on the comparison of different algorithms in only distributed scheme or in only centralized scheme. However, we believe that the network blocking probability of these two connection management schemes depends, to a great extent, on the network traffic patterns and reservation times. Our simulation results reveal that the performance improvement (in terms of blocking probability) of …

An Analytical Model For Virtual Topology Reconfiguration In Optical Networks And A Case Study, Xi Yang, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

An analytical model for Virtual Topology Reconfiguration (VTR) in optical networks is developed. It aims at the optical networks with a circuit-based data plane and an IPlike control plane. By identifying and analyzing the important factors impacting the network performance due to VTR operations on both planes, we can compare the benefits and penalties of different VTR algorithms and policies. The best VTR scenario can be adaptively chosen from a set of such algorithms and policies according to the real-time network situations. For this purpose, a cost model integrating all these factors is created to provide a comparison criterion independent …

Two Algorithms For Shaped-Based Porosity Measures, Leen-Kiat Soh

School of Computing: Technical Reports

In this paper, we present two algorithms for shape-based porosity measures. Specifically, we describe two innovative attributes called perimeter porosity and area porosity as feature descriptors. Perimeter porosity refers to how “porous” or “weak” an image object is, while area porosity determines the degree of “branchiness” of an object. We show the applicability of the two measures through a SAR sea ice image classification example.

Dynamic Routing In Translucent Wdm Optical Networks, Xi Yang, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

Translucent WDM optical networks use sparse placement of regenerators to overcome the impairments and wavelength contention introduced by fully transparent networks, and achieve a performance close to fully opaque networks with much less cost. Our previous study proved the feasibility of translucent networks using sparse regeneration technique. We addressed the placement of regenerators based on static schemes allowing only fixed number of regenerators at fixed locations. This paper furthers the study by proposing a suite of dynamical routing schemes. Dynamic allocation, advertisement and discovery of regeneration resources are proposed to support sharing transmitters and receivers between regeneration and access functions. …

A Set Of New Sea Ice Feature Descriptors For Sar Images, Leen-Kiat Soh

School of Computing: Technical Reports

In this paper, we present a set of algorithms for describing sea ice features in SAR images. These algorithms we have implemented and incorporated in the ARKTOS software package, an intelligent sea ice classification. These algorithms have unique characteristics. Some are extensions or adaptations of existing image processing techniques to the specific problem domain of satellite sea ice classification, while some are innovative designs, inspired by the aforementioned problem domain. These feature descriptors may be generalized to other remote sensing applications.

Dynamic Traffic Grooming Algorithms For Reconfigurable Sonet Over Wdm Networks, Shu Zhang, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

The emergence of Wavelength Division Multiplexing (WDM) technology provides the capability for increasing the bandwidth of Synchronous Optical Network (SONET) rings by grooming low-speed traffic streams onto different high-speed wavelength channels. Since the cost of SONET add-drop multiplexers (SADM) at each node dominates the total cost of these networks, how to assign the wavelength, groom in the traffic and bypass the traffic through the intermediate nodes has received a lot of attention from researchers recently.

Constraint Modeling And Reformulation In The Context Of Academic Task Assignment, Robert Glaubius, Berthe Y. Choueiry

School of Computing: Conference and Workshop Papers

We discuss the modeling and reformulation of a resource allocation problem, the assignment of graduate teaching assistants (GTAs) to courses. Our research contributes the following:

• Formulation of the GTA assignment problem as a nonbinary CSP.

• Design of a new convention for consistency checking to deal with over-constrained problem.

• Definition of a new network-decomposable nonbinary confinement constraint.

• Evaluation of the reformulation of confinement and equality constraints on 3 real-world data sets.

Constraint Modeling And Reformulation In The Context Of Academic Task Assignment, Robert Glaubius, Berthe Y. Choueiry

School of Computing: Conference and Workshop Papers

We discuss the modeling and reformulation of a resource allocation problem, the assignment of Graduate Teaching Assistants to courses in the University of Nebraska-Lincoln Computer Science Department. We formulate this problem as a non-binary Constraint Satisfaction Problem (CSP) and provide a new convention for consistency checking to deal with the over-constraindness of the problem and the practical requirement of our application. We introduce a new decomposable non-binary constraint, which we call confinement constraint, and describe its relevance in practical requirements of our application. We introduce an new decomposable non-binary constraint, which we call confinement constraint, and describe its relevance in …

A Novel Method To Improve The Test Efficiency Of Vlsi Tests, Hailong Cui, Sharad C. Seth, Shashank K. Mehta

School of Computing: Conference and Workshop Papers

This paper considers reducing the cost of test application by permuting test vectors to improve their defect coverage. Algorithms for test reordering are developed with the goal of minimizing the test cost. Best and worst case bounds are established for the performance of a reordered sequence compared to the original sequence of test application. SEMATECH test data and simulation results are used throughout to illustrate the ideas.

Knowledge Management Mechanisms In E-Commerce: A Study Of Online Retailing And Auction Sites, Fiona Fui-Hoon Nah, Keng Siau, Yuhong Tian, Min Ling

Research Collection School Of Computing and Information Systems

Knowledge management is vital to a company's success in this e-commerce era. Not only has the topic of knowledge management attracted much research attention lately, but the management of customer knowledge is also becoming increasingly important. Despite its significance, few research studies have systematically investigated knowledge management in the e-commerce context. None of the studies we reviewed looked at how knowledge management mechanisms were employed in e-commerce. This research presents a comprehensive analysis of the knowledge management mechanisms employed by 14 e-commerce sites that were rated as being the best by Gomez.com, an independent Internet quality measurement firm. Specifically, we …

Acceptable Internet Use Policy, Keng Siau, Fiona Fui-Hoon Nah, Limei Teng

Research Collection School Of Computing and Information Systems

Surveying use policies of three organizations--- educational institutions, ISPs, and non-ISPs.

Enhancing Profiles For Anomaly Detection Using Time Granularities, Yingjiu Li, Ningning Wu, X. Sean Wang, Sushil Jajodia

Research Collection School Of Computing and Information Systems

Recently, association rules have been used to generate profiles of normal behavior for anomaly detection. However, the time factor (especially in terms of multiple time granularities) has not been utilized extensively in generation of these profiles. In reality, user behavior during different time intervals may be very different. For example, the normal number and duration of FTP connections may vary from working hours to midnight, from business day to weekend or holiday. Furthermore, these variations may depend on the day of the month or the week. This paper proposes to build profiles using temporal association rules in terms of multiple …

A Comparison Of The Use Of Artificial Neural Networks, Fractal Time Series And Fractal Neural Networks In Financial Forecasts, Beverly A. Swisshelm

CCAC Theses and Dissertations

Effective prediction of future financial states has been a major quest for groups ranging from national governments to individual investors. The size, diversity and complexity of financial markets make traditional statistical methods ineffective in predicting beyond a very short time frame. Alternative models using artificial neural networks and fractal time series have had better results in long-term predictions, but still do not work in all situations. This dissertation combined features of artificial neural networks and fractal time series to create a fractal neural network. Fractals exhibit repetitive patterns when a unit is broken down into its components. This similarity property …

A Personel Note, Leopold B. Felsen

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.

Iterative Solution Of Field Problems With A Varying Physical Parameter, Anton G. Tijhuis, Martijn C. Van Beurden, A. Peter M. Zwamborn

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, linear field problems with a varying physical parameter are solved with the conjugate-gradient FFT method and a dedicated extrapolation procedure for generating the initial estimate. The scheme is formulated and illustrated for two simple example problems. The importance of the choice of the stop criterion and the step size are demonstrated for the case of a straight thin-wire segment. A brief summary is given of the applications that have appeared in the open literature until now, and actual three-dimensional scattering problems for a rectangular conducting plate and an inhomogeneous, dispersive dielectric body are discussed. Finally, the case …

Network--Oriented Modeling Of Radiating Electromagnetic Structures, Peter Russer

Turkish Journal of Electrical Engineering and Computer Sciences

The application of network-oriented modeling for radiating electromagnetic structures is investigated. Network methods are applied to the field problem using the segmentation technique and by specifying canonical Foster representations as compact models of reciprocal linear lossless electromagnetic structures. Connection between different subdomains is obtained via connection circuits exhibiting only ideal transformers. In the case of radiating structures, the complete structure is embedded into a sphere and the field outside the sphere is expanded into orthogonal spherical TM- and TE- waves. For each radiation mode a Cauer canonic circuit representation is given.