Digital Commons Network^™

Q-Pod: Deployable And Scalable End System Support For Enabling Qos In Legacy Enterprise Systems, Asad Khan Awan, Kihong Park

Department of Computer Science Technical Reports

No abstract provided.

Fast Algorithms For Fragment Based Completion In Images Of Natural Scenes, Siddharth Rajkumar Borikar

Electronic Theses and Dissertations

Textures are used widely in computer graphics to represent fine visual details and produce realistic looking images. Often it is necessary to remove some foreground object from the scene. Removal of the portion creates one or more holes in the texture image. These holes need to be filled to complete the image. Various methods like clone brush strokes and compositing processes are used to carry out this completion. User skill is required in such methods. Texture synthesis can also be used to complete regions where the texture is stationary or structured. Reconstructing methods can be used to fill in large-scale …

Investigation Of Implementation Techniques For Backpropagation Neural Networks., John Culloty

Theses

Artificial neural networks are biologically inspired computational methods that have the ability to approximate discrete, real and vector valued target functions. For some problem domains this ability makes neural networks a more appealing solution than traditional computational techniques. Such problem domains typically contain a large number of parameters that are interrelated in a complex and often unknown manner. This makes rule based solutions all but impossible. However another feature of such problem domains is the presence of large volumes of real world data that can be used to tram a neural network until it learns the solution.

One of the …

Investigation Of Implementation Techniques For Backpropagation Neural Networks, John Culloty

Theses

Artificial neural networks are biologically inspired computational methods that have the ability to approximate discrete, real and vector valued target functions. For some problem domains this ability makes neural networks a more appealing solution than traditional computational techniques. Such problem domains typically contain a large number of parameters that are interrelated in a complex and often unknown manner. This makes rule based solutions all but impossible. However another feature of such problem domains is the presence of large volumes of real world data that can be used to tram a neural network until it learns the solution.

One of the …

A Toolkit For Xml-Based And Process-Oriented Application Integration, Volker Münch

Theses

Systems integration is hard work; different architectures with different interfaces and an innumerable amount of Legacy applications with non-standard interfaces exist. However the needs to meet changing business requirements and to implement faster and optimised procedures within an enterprise and in cooperation with other external enterprises mean that there is a continuing demand for such integration strategies and products. Integration was often an activity separate from system development and could not be accomplished without re-involving system designers and developers. Such a process is therefore inefficient and costly. This thesis proposes a process-oriented integration strategy that combines the tasks of integration …

Computational Geometry Column 45, Joseph O'Rourke

Computer Science: Faculty Publications

The algorithm of Edelsbrunner for surface reconstruction by "wrapping" a set of points in R³ is described.

Better Foreground Segmentation Through Graph Cuts, Nicholas Howe, Alexandra Deschamps

Computer Science: Faculty Publications

For many tracking and surveillance applications, background subtraction provides an effective means of segmenting objects moving in front of a static background. Researchers have traditionally used combinations of morphological operations to remove the noise inherent in the background-subtracted result. Such techniques can effectively isolate foreground objects, but tend to lose fidelity around the borders of the segmentation, especially for noisy input. This paper explores the use of a minimum graph cut algorithm to segment the foreground, resulting in qualitatively and quantitiatively cleaner segmentations. Experiments on both artificial and real data show that the graphbased method reduces the error around segmented …

Real-Time 4d Tumor Tracking And Modeling From Internal And External Fiducials In Fluoroscopy, Johanna Brewer, Margrit Betke, David P. Gierga, George T.Y. Chen

Computer Science: Faculty Publications

Fluoroscopy is currently used in treatment planning for patients undergoing radiation therapy. Radiation oncologists would like to maximize the amount of dose the tumor receives and minimize the amount delivered to the surrounding tissues. During treatment, patients breathe freely and so the tumor location will not be fixed. This makes calculating the amount of dose delivered to the tumor, and verifying that the tumor actually receives that dose, difficult. We describe a correlation- based method of tracking the two-dimensional (2D) motion of internal markers (surgical clips) placed around the tumor. We established ground truth and evaluated the accuracy of the …

Anomaly-Free Component Adaptation With Class Overriding, Atanas Radenski

Mathematics, Physics, and Computer Science Faculty Articles and Research

Software components can be implemented and distributed as collections of classes, then adapted to the needs of specific applications by means of subclassing. Unfortunately, subclassing in collections of related classes may require re-implementation of otherwise valid classes just because they utilize outdated parent classes, a phenomenon that is referred to as the subclassing anomaly. The subclassing anomaly is a serious problem since it can void the benefits of component-based programming altogether. We propose a code adaptation language mechanism called class overriding that is intended to overcome the subclassing anomaly. Class overriding does not create new and isolated derived classes as …

Pperfgrid: A Grid Services-Based Tool For The Exchange Of Heterogeneous Parallel Performance Data, John Jared Hoffman

Dissertations and Theses

This thesis details the approach taken in developing PPerfGrid. Section 2 discusses other research related to this project. Section 3 provides general background on the technologies utilized in PPerfGrid, focusing on the components that make up the Grid services architecture. Section 4 provides a description of the architecture of PPerfGrid. Section 5 details the implementation of PPerfGrid. Section 6 presents tests designed to measure the overhead and scalability of the PPerfGrid application. Section 7 suggests future work, and Section 8 concludes the thesis.

A Study In Modeling Low-Conservation Protein Superfamilies, Chang Wang, Stephen Scott, Jun Zhang, Qingping Tao, Dmitri E. Fomenko, Vadim N. Gladyshev

School of Computing: Technical Reports

We present several algorithms for identification of new proteins in superfamilies with low primary sequence conservation. The low conservation of primary sequence in protein superfamilies such as Thioredoxin-fold (Trx-fold) makes conventional methods such as hidden Markov models (HMMs) difficult to use. Therefore, we use structural properties to build our classifiers. These structural properties include secondary structure patterns as well as various properties of the residues in the protein sequences. We use this information to model proteins via hidden Markov models, support vector machines and algorithms in the multiple-instance learning model. In 20-fold jack-knife tests, some of our models performed well, …

Variable Rate Execution, Steve Goddard, Xin Liu

School of Computing: Technical Reports

We present a task model for adaptive real-time tasks in which a task’s execution rate requirements are allowed to change at any time. The model, variable rate execution (VRE), is an extension of the rate-based execution (RBE) model. We relax the constant execution rate assumption of canonical realtime task models by allowing both the worst case execution time (WCET) and the period to be variable. The VRE model also supports tasks joining and leaving the system at any time. Another advantage of the new task model is that the exact execution rate need not be known for soft real-time or …

A Load-Balancing Spare Capacity Reallocation Approach In Service-Rich Sonet Metro Mesh Networks, Lu Shen, Xi Yang, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

The next-generation SONET metro network is evolving into a service-rich infrastructure. At the edge of such a network, multi-service provisioning platforms (MSPPs) provide efficient data mapping enabled by Generic Framing Procedure (GFP) and Virtual Concatenation (VC). The core of the network tends to be a meshed architecture equipped with Multi-Service Switches (MSSs). In the context of these emerging technologies, we propose a load-balancing spare capacity reallocation approach to improve network utilization in the next-generation SONET metro networks. Using our approach, carriers can postpone network upgrades, resulting in increased revenue with reduced capital expenditures (CAPEX). For the first time, we consider …

A Dynamic Real-Time Scheduling Algorithm For Reduced Energy Consumption, Rohini Krishnapura, Steve Goddard, Ala' Adel Qadi

School of Computing: Technical Reports

In embedded real-time systems, Dynamic Power Management (DPM) techniques have traditionally focused on reducing the dynamic power dissipation that occurs when a CMOS gate switches in a processor. Less attention has been given to processor leakage power or power consumed by I/O devices and other subsystems. I/O-based DPM techniques, however, have been extensively researched in non-real-time systems. These techniques focus on switching I/O devices to low power states based on various policies and are not applicable to real-time environments because of the non-deterministic nature of the policies. The challenge in conserving energy in embedded real-time systems is thus to reduce …

Survivable Virtual Topology Routing Under Shared Risk Link Groups In Wdm Networks, Ajay Todimala, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

Network survivability is one of the most important issues in the design of optical WDM networks. In this work we study the problem of survivable routing of a virtual topology on a physical topology with Shared Risk Link Groups (SRLG). The survivable virtual topology routing problem against single-link failures in the physical topology is proved to be NP-complete in [1]. We prove that survivable virtual topology routing problem against SRLG/node failures is also NP-complete. We present an improved integer linear programming (ILP) formulation (in comparison to [1]) for computing the survivable routing under SRLG/node failures. Using an ILP solver, we …

Rerouting Schemes For Dynamic Traffic Grooming In Optical Wdm Mesh Networks, Wang Yao, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

Traffic grooming in optical WDM mesh networks is a two-layer routing problem to effectively pack low-rate connections onto high-rate lightpaths, which, in turn, are established on wavelength links. In this work, we employ the rerouting approach to improve the network throughput under the dynamic traffic model. We propose two rerouting schemes, rerouting at lightpath level (RRAL) and rerouting at connection level (RRAC). A qualitative comparison is made between RRAL and RRAC. We also propose the critical-wavelength-avoiding one-lightpath-limited (CWA-1L) and critical-lightpath-avoiding one-connection-limited (CLA-1C) rerouting heuristics, which are based on the two rerouting schemes respectively. Simulation results show that rerouting reduces the …

Special Section On The Algorithmics Of Software Model Checking — Introductory Paper, Matthew Dwyer, Stefan Leue

School of Computing: Faculty Publications

The term “software model checking” has recently been coined to refer to a flourishing area of research in software verification – the formal, automated analysis of program source code. Software model checking is considered an important application of classical model checking, where the model of a software system is analyzed in an automated fashion for compliance with a property specification. While classical model checking assumes the existence of an abstract model of the software system to be analyzed, in software model checking the emphasis is on directly analyzing program code given in a standard programming language, such as Java or …

An Analysis Of Mcmc Sampling Methods For Estimating Weighted Sums In Winnow, Qingping Tao, Stephen Scott

School of Computing: Technical Reports

Chawla et al. introduced a way to use the Markov chain Monte Carlo method to estimate weighted sums in multiplicative weight update algorithms when the number of inputs is exponential. But their algorithm still required extensive simulation of the Markov chain in order to get accurate estimates of the weighted sums. We propose an optimized version of Chawla et al.’s algorithm, which produces exactly the same classifications while often using fewer Markov chain simulations. We also apply three other sampling techniques and empirically compare them with Chawla et al.’sMetropolis sampler to determine how effective each is in drawing good samples …

Using Source-Code Analysis To Help End-User Programmers Create Dependable Software, Gregg Rothermel

School of Computing: Conference and Workshop Papers

Not long ago, most software was written by professional programmers, who could be presumed to have an interest in software engineering methodologies and in tools and techniques for improving software dependability. Today, however, a great deal of software is written not by professionals but by end-users, who create applications such as multimedia simulations, dynamic web pages, and spreadsheets. Applications such as these are often used to guide important decisions or aid in important tasks, and it is important that they be sufficiently dependable, but evidence shows that they frequently are not. For example, studies have shown that a large percentage …

Empirical Studies Of Test Case Prioritization In A Junit Testing Environment, Hyunsook Do, Gregg Rothermel, Alex Kinneer

School of Computing: Conference and Workshop Papers

Test case prioritization provides a way to run test cases with the highest priority earliest. Numerous empirical studies have shown that prioritization can improve a test suite’s rate of fault detection, but the extent to which these results generalize is an open question because the studies have all focused on a single procedural language, C, and a few specific types of test suites. In particular, Java and the JUnit testing framework are being used extensively in practice, and the effectiveness of prioritization techniques on Java systems tested under JUnit has not been investigated. We have therefore designed and performed a …

Evaluating Consistency Algorithms For Temporal Metric Constraints, Yang Shi, Anagh Lal, Berthe Y. Choueiry

School of Computing: Conference and Workshop Papers

We study the performance of some known algorithms for solving the Simple Temporal Problem (STP) and the Temporal Constraint Satisfaction Problem (TCSP). In particular, we empirically compare the Bellman-Ford (BF) algorithm and its incremental version (incBF) by (Cesta & Oddi 1996) to the ΔSTP of (Xu & Choueiry 2003a). Among the tested algorithms, we show that ΔSTP is the most efficient for determining the consistency of an STP, and that incBF combined with the heuristics of (Xu & Choueiry 2003b) is the most efficient for solving the TCSP. We plan to improve ΔSTP by exploiting incrementality as in incBF and …

A Nonparametric Classifier For Unsegmented Text, George Nagy, Ashutosh Joshi, Mukkai Krishnamoorthy, Yu Lin, Daniel Lopresti, Shashank K. Mehta, Sharad C. Seth

School of Computing: Conference and Workshop Papers

Symbolic Indirect Correlation (SIC) is a new classification method for unsegmented patterns. SIC requires two levels of comparisons. First, the feature sequences from an unknown query signal and a known multi-pattern reference signal are matched. Then, the order of the matched features is compared with the order of matches between every lexicon symbolstring and the reference string in the lexical domain. The query is classified according to the best matching lexicon string in the second comparison. Accuracy increases as classified feature-and-symbol strings are added to the reference string.

Disjoint Np-Pairs, Christian Glasser, Alan L. Selman, Samik Sengupta, Liyu Zhang

Computer Science Faculty Publications

We study the question of whether the class DisjNP of disjoint pairs (A, B) of NP-sets contains a complete pair. The question relates to the question of whether optimal proof systems exist, and we relate it to the previously studied question of whether there exists a disjoint pair of NP-sets that is NP-hard. We show under reasonable hypotheses that nonsymmetric disjoint NP-pairs exist, which provides additional evidence for the existence of P-inseparable disjoint NP-pairs. We construct an oracle relative to which the class of disjoint NP-pairs does not have a complete pair; an oracle relative to which …

Ethical Reflections On Cyberstalking, Frances Grodzinsky, Herman T. Tavani

School of Computer Science & Engineering Faculty Publications

This essay examines some ethical aspects of stalking behavior in cyberspace. We have argued elsewhere that recent online stalking incidents raise a wide range of ethical concerns, including issues affecting gender (Grodzinsky and Tavani, 2001), personal privacy (Tavani and Grodzinsky, 2002), and physical vs. virtual harm (Grodzinsky and Tavani, 2002). The primary axis of discussion in this essay has to do with implications that cyberstalking has for our notion of moral responsibility, both at the collective (or group) and individual levels. For example, do collectivities and organizations such as Internet service providers (ISPs) have any moral obligations to cyberstalking victims, …

Visual Expectations: Using Machine Learning To Identify Patterns In Psychological Data, Skyler Place

Honors Theses

The goal of this project was to utilize the tools of machine learning to evaluate the data obtained through experiments in psychology. Advanced pattern finding algorithms are an effective approach to analyzing large sets of data, from any domain of science. Consequently, we have a psychological question and hypothesis, and a separate machine learning technique to assess these claims. The realm of psychology that I focused on is visual cognition, and how an individual's knowledge affects how they see the world. This alteration of visual data is a part of perception -when the brain enhances the data coming in from …

A Secure And Privacy Enhanced Location-Based Service Transaction Protocol In Ubiquitous Computing Environment, Konidala Divyan, Robert H. Deng, Jianying Zhou, Kwanjo Kim

Research Collection School Of Computing and Information Systems

Nowadays mobile phones and PDAs are part and parcel of our lives. By carrying a portable mobile device with us all the time we are already living in partial Pervasive Computing Environment (PCE) that is waiting to be exploited very soon. One of the advantages of pervasive computing is that it strongly supports the deployment of Location-Based Service(s) (LBSs). In PCE, there would be many competitive service providers (SPs) trying to sell different or similar LBSs to users. In order to avail a particular service, it becomes very di#cult for a low-computing and resourcepoor mobile device to handle many such …

Powerful Change Part 2: Reducing The Power Demands Of Mobile Devices, Rajesh Krishna Balan

Research Collection School Of Computing and Information Systems

Consumers expect their mobile devices to be small and light, have a decent battery lifetime, and still be powerful enough to run all their desired applications. The need to satisfy such consumer demands has driven mobile-device manufacturers to make products (such as PDAs and cell phones) that match these needs. However, this inevitably requires tradeoffs. Building smaller, lighter devices requires sacrificing the device's battery capacity because battery technology is still fairly dense and heavy, and contributes most of a mobile device's size and weight. But, mobile devices with the required resources to run useful desktop applications need additional battery power …

Evaluating The Usability Of A Group Support System Using Co-Discovery, Keng Siau

Research Collection School Of Computing and Information Systems

Group Support Systems (GSSs) have emerged as a new type of information system to aid group decision-making. With the proliferation of such systems in organizations, evaluation of GSSs is becoming increasingly important. This paper reports the evaluation of an existing GSS. Our usability framework consists of nine dimensions: visual clarity, consistency, compatibility, informative feedback, explicitness, flexibility and control, error prevention and correction, ease of learning, and ease of use. We make use of the co-discovery method where teams of two participants perform tasks together while being observed. The study involves questionnaires and interview sessions. The strengths and weaknesses of the …

Development Of A Systems Engineering Model Of The Chemical Separations Process, Yitung Chen, Darrell Pepper, Sean Hsieh

Separations Campaign (TRP)

The chemical processing of used nuclear fuel is an integral component of any strategy for the transmutation of nuclear waste. Due to the large volume of material that must be handled in this first step of the transmutation process, the efficiency of the separations process is a key factor in the potential economic viability of the transmutation strategies. The ability to optimize the chemical separation systems is vital to ensure the feasibility of the transmutation program.

Systems analysis, or total systems modeling, is one of the strongest tools available to researchers for understanding and optimizing complex systems such as chemical …

Object Tracking And Activity Recognition In Video Acquired Using Mobile Cameras, Alper Yilmaz

Electronic Theses and Dissertations

Due to increasing demand on deployable surveillance systems in recent years, object tracking and activity recognition are receiving considerable attention in the research community. This thesis contributes to both the tracking and the activity recognition components of a surveillance system. In particular, for the tracking component, we propose two different approaches for tracking objects in video acquired by mobile cameras, each of which uses a different object shape representation. The first approach tracks the centroids of the objects in Forward Looking Infrared Imagery (FLIR) and is suitable for tracking objects that appear small in airborne video. The second approach tracks …