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Multi-Level Modeling Of Software On Hardware In Concurrent Computation, Joann M. Paul, Arne Suppe, Henele I. Adams, Donald E. Thomas Apr 2002

Multi-Level Modeling Of Software On Hardware In Concurrent Computation, Joann M. Paul, Arne Suppe, Henele I. Adams, Donald E. Thomas

Research Collection School Of Computing and Information Systems

The fundamental modeling differences between hardware and software modeling can be thought of as reasoning about connectedness vs. reasoning about interleaved (shared) access to resources. A natural design hierarchy for physical systems is component-based because of the existence of a consistent basis for interconnect between design levels. However, performance modeling and design of concurrent, programmable systems require new ways of thinking about what it means to abstract detail, add detail and partition a model of software executing on hardware. We motivate frequency interleaving (FI) as a common simulation foundation for these systems because it resolves flow and partitioning with software …

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Driving In Traffic: Short-Range Sensing For Urban Collision Avoidance, Chuck Thorpe, Dave Duggins, Jay Gowdy, Rob Maclaughlin, Christoph Mertz, Mel Siegel, Arne Suppe, Bob Wang, Teruko Yata Apr 2002

Driving In Traffic: Short-Range Sensing For Urban Collision Avoidance, Chuck Thorpe, Dave Duggins, Jay Gowdy, Rob Maclaughlin, Christoph Mertz, Mel Siegel, Arne Suppe, Bob Wang, Teruko Yata

Research Collection School Of Computing and Information Systems

Intelligent vehicles are beginning to appear on the market, but so far their sensing and warning functions only work on the open road. Functions such as runoff-road warning or adaptive cruise control are designed for the uncluttered environments of open highways. We are working on the much more difficult problem of sensing and driver interfaces for driving in urban areas. We need to sense cars and pedestrians and curbs and fire plugs and bicycles and lamp posts; we need to predict the paths of our own vehicle and of other moving objects; and we need to decide when to issue …

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Embedded Software Programming To Develop A Command Line User Interface For Monitoring And Debugging A Manually Driven Gas Regulator Control System, Syed N. Hyder Apr 2002

Embedded Software Programming To Develop A Command Line User Interface For Monitoring And Debugging A Manually Driven Gas Regulator Control System, Syed N. Hyder

Electrical & Computer Engineering Theses & Dissertations

This thesis presents a complete embedded programming model and software codes for a command-line user interface for CONCOA's gas regulator control system. Control Corporation of America (CONCOA) manufactures high-pressure gas regulators, which mechanically control the pressure at their outlets. Since the control system is based on mechanical regulators, adding or stopping gas flow from the system can cause manifold fluctuation that could further cause the pressure to rise or fall with time. The main motivation for developing a command line user interface is to provide a centralized computer control to monitor and debug the gas regulator control system electronically by …

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A Formal Object Model For Layered Networks To Support Verification And Simulation, Rasha M. B. E. Morsi Apr 2002

A Formal Object Model For Layered Networks To Support Verification And Simulation, Rasha M. B. E. Morsi

Electrical & Computer Engineering Theses & Dissertations

This work presents an abstract formal model of the interconnection structure of the Open Systems Interconnection Reference Model (OSI-RM) developed using Object-Oriented modeling principles permitting it to serve as a re-usable platform in supporting the development of simulations and formal methods applied to layered network protocols. A simulation of the object model using MODSIM III was developed and Prototype Verification System (PVS) was used to show the applicability of the object model to formal methods by formally specifying and verifying a Global Systems for Mobile communications (GSM) protocol. This application has proved to be successful in two aspects. The first …

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Infopipes: An Abstraction For Multimedia Streaming, Andrew P. Black, Huang Jie, Rainer Koster, Jonathan Walpole, Calton Pu Apr 2002

Infopipes: An Abstraction For Multimedia Streaming, Andrew P. Black, Huang Jie, Rainer Koster, Jonathan Walpole, Calton Pu

Computer Science Faculty Publications and Presentations

To simplify the task of building distributed streaming applications, we propose a new abstraction for information flow – Infopipes. Infopipes make information flow primary, not an auxiliary mechanism that is hidden away. Systems are built by connecting predefined component Infopipes such as sources, sinks, buffers, filters, broadcasting pipes, and multiplexing pipes. The goal of Infopipes is not to hide communication, like an RPC system, but to reify it: to represent communication explicitly as objects that the program can interrogate and manipulate. Moreover, these objects represent communication in application-level terms, not in terms of network or process implementation.

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Robust Face Representation And Recognition Under Low Resolution And Difficult Lighting Conditions, Mohammad Moinul Islam Apr 2002

Robust Face Representation And Recognition Under Low Resolution And Difficult Lighting Conditions, Mohammad Moinul Islam

Electrical & Computer Engineering Theses & Dissertations

This dissertation focuses on different aspects of face image analysis for accurate face recognition under low resolution and poor lighting conditions. A novel resolution enhancement technique is proposed for enhancing a low resolution face image into a high resolution image for better visualization and improved feature extraction, especially in a video surveillance environment. This method performs kernel regression and component feature learning in local neighborhood of the face images. It uses directional Fourier phase feature component to adaptively lean the regression kernel based on local covariance to estimate the high resolution image. For each patch in the neighborhood, four directional …

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The Effect Of Model Formulation On The Comparative Performance Of Artificial Neural Networks And Regression, Michael F. Cochrane Apr 2002

The Effect Of Model Formulation On The Comparative Performance Of Artificial Neural Networks And Regression, Michael F. Cochrane

Engineering Management & Systems Engineering Theses & Dissertations

Multiple linear regression techniques have been traditionally used to construct predictive statistical models, relating one or more independent variables (inputs) to a dependent variable (output). Artificial neural networks can also be constructed and trained to learn these complex relationships, and have been shown to perform at least as well as linear regression on the same data sets. Research on the use of neural network models as alternatives to multivariate linear regression has focused predominantly on the effects of sample size, noise, and input vector size on the comparative performance of these two modeling techniques. However, research has also shown that …

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Rapid Heterogeneous Ad Hoc Connection Establishment: Accelerating Bluetooth Inquiry Using Irda, Trevor Clifton, Derek D. Joos, Charles D. Knutson, Ryan W. Woodings Mar 2002

Rapid Heterogeneous Ad Hoc Connection Establishment: Accelerating Bluetooth Inquiry Using Irda, Trevor Clifton, Derek D. Joos, Charles D. Knutson, Ryan W. Woodings

Faculty Publications

Bluetooth device discovery is a time-intensive phase of the Bluetooth connection-establishment procedure. In this paper we propose a technique that integrates existing IrDA technology with Bluetooth technology to improve the ad hoc connection establishment time of Bluetooth devices. We accomplish this improvement by first establishing an IrDA connection between two devices equipped with both Bluetooth and IrDA capabilities and then exchanging Bluetooth device discovery information via the established IrDA connection. As a result of this cooperative exchange, the devices are able to bypass the time-intensive Bluetooth device discovery procedure. Our research shows that IrDA-assisted Bluetooth connection establishment is up to …

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Characterizing Usage Of A Campus-Wide Wireless Network, David Kotz, Kobby Essien Mar 2002

Characterizing Usage Of A Campus-Wide Wireless Network, David Kotz, Kobby Essien

Computer Science Technical Reports

Wireless local-area networks (WLANs) are increasingly common, but little is known about how they are used. A clear understanding of usage patterns in real WLANs is critical information to those who develop, deploy, and manage WLAN technology, as well as those who develop systems and application software for wireless networks. This paper presents results from the largest and most comprehensive trace of network activity in a large, production wireless LAN. For eleven weeks we traced the activity of nearly two thousand users drawn from a general campus population, using a campus-wide network of 476 access points spread over 161 buildings. …

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Suitability Of Unidata Metapps For Incorporation In Platform-Independent User-Customized Aviation Weather Products Generation Software, Harmen P. Visser Mar 2002

Suitability Of Unidata Metapps For Incorporation In Platform-Independent User-Customized Aviation Weather Products Generation Software, Harmen P. Visser

Theses and Dissertations

The Air Force Combat Climatology Center (AFCCC) is tasked to provide long-range seasonal forecasts for worldwide locations. Currently, the best long-range temperature forecasts the weather community has are the climatological standard normals. This study creates a stepping-stone into the solution of long-range forecasting by finding a process to predict temperatures better than those using climatological standard normals or simple frequency distributions of occurrences. Northern Hemispheric teleconnection indices and the standardized Southern Oscillation index are statistically compared to three-month summed Heating Degree Days (HDDs) and Cooling Degree Days (CDDs) at 14 U.S. locations. First, linear regression was accomplished. The results showed …

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Using An Inductive Learning Algorithm To Improve Antibody Generation In A Single Packet Computer Defense Immune System, Russell J. Aycock Mar 2002

Using An Inductive Learning Algorithm To Improve Antibody Generation In A Single Packet Computer Defense Immune System, Russell J. Aycock

Theses and Dissertations

Coherent optical sources in the mid-infrared region (mid-IR) are important fundamental tools for infrared countermeasures and battlefield remote sensing. Nonlinear optical effects can be applied to convert existing near-IR laser sources to radiate in the mid-IR. This research focused on achieving such a conversion with a quasi-phase matched optical parametric oscillators using orientation-patterned gallium arsenide (OPGaAs), a material that can be quasi-phased matched by periodically reversing the crystal structure during the epitaxial growth process. Although non-linear optical conversion was not ultimately achieved during this research, many valuable lessons were learned from working with this material. This thesis reviews the theory …

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Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 18, Number 6, March 2002, College Of Engineering And Computer Science, Wright State University Mar 2002

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 18, Number 6, March 2002, 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.

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Pattern Classification Using A Quantum System, Dan A. Ventura Mar 2002

Pattern Classification Using A Quantum System, Dan A. Ventura

Faculty Publications

We consider and compare three approaches to quantum pattern classification, presenting empirical results from simulations.

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An Intelligent Middleware For Linear Correlation Discovery, Cecil Chua, Roger Hsiang-Li Chiang, Ee Peng Lim Mar 2002

An Intelligent Middleware For Linear Correlation Discovery, Cecil Chua, Roger Hsiang-Li Chiang, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Although it is widely accepted that research from data mining, knowledge discovery, and data warehousing should be synthesized, little research addresses the integration of existing data management and analysis software. We develop an intelligent middleware that facilitates linear correlation discovery, the discovery of associations between attributes and attribute groups. This middleware integrates data management and data analysis tools to improve traditional data analysis in three perspectives: (1) identify appropriate linear correlation functions to perform based on the semantics of a data set; (2) execute appropriate functions contained in the data analysis packages; and (3) derive useful knowledge from data analysis.

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Idmp-Based Fast Handoffs And Paging In Ip-Based 4g Mobile Networks, Archan Misra, Subir Das, Anthony Mcauley, Sajal K. Das Mar 2002

Idmp-Based Fast Handoffs And Paging In Ip-Based 4g Mobile Networks, Archan Misra, Subir Das, Anthony Mcauley, Sajal K. Das

Research Collection School Of Computing and Information Systems

We consider the use of our previously proposed Intra-Domain Mobility Management Protocol (IDMP) in fourth-generation mobile networks. On evaluating the heterogeneous access technologies, cellular layouts, and application characteristics of 4G environments, we realize a need to reduce both handoff latency and the frequency of mobility-related signaling. We first present IDMP's fast intradomain handoff mechanism that uses a duration-limited proactive packet multicasting solution. We quantify the expected buffering requirements of our proposed multicasting scheme for typical 4G network characteristics and compare it with alternative IP-based fast handoff solutions. We also present a paging scheme under IDMP that replicates the current cellular …

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Portable High-Performance Indexing For Vector Product Format Spatial Databases, Engin Colak Mar 2002

Portable High-Performance Indexing For Vector Product Format Spatial Databases, Engin Colak

Theses and Dissertations

Geo-spatial databases have an overall performance problem because of their complexity and large size. For this reason, many researchers seek new ways to improve the overall performance of geo-spatial databases. Typically, these research efforts are focused on complex indexing structures and query processing methods to capture the relationships between the individual features of fully-functional geo-spatial databases. Visualization applications, such as combat simulators and mission planning tools, suffer from the general performance problems associated with geo-spatial databases. This research focuses on building a high-performance geo-spatial database for visualization applications. The main approach is to simplify the complex data model and to …

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Bubble World - A Novel Visual Information Retrieval Technique, Christopher L. Van Berendonck Mar 2002

Bubble World - A Novel Visual Information Retrieval Technique, Christopher L. Van Berendonck

Theses and Dissertations

With the tremendous growth of published electronic information sources in the last decade and the unprecedented reliance on this information to succeed in day-to-day operations, comes the expectation of finding the right information at the right time. Sentential interfaces are currently the only viable solution for searching through large infospheres of unstructured information, however, the simplistic nature of their interaction model and lack of cognitive amplification they can provide severely limit the performance of the interface. Visual information retrieval systems are emerging as possible candidate replacements for the more traditional interfaces, but many lack the cognitive framework to support the …

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Multi-Objective Mission Route Planning Using Particle Swarm Optimization, Kursat Yavuz Mar 2002

Multi-Objective Mission Route Planning Using Particle Swarm Optimization, Kursat Yavuz

Theses and Dissertations

The Mission Routing Problem (MRP) is the selection of a vehicle path starting at a point, going through enemy terrain defended by radar sites to get to the target(s) and returning to a safe destination (usually the starting point). The MRP is a three-dimensional, multi-objective path search with constraints such as fuel expenditure, time limits, multi-targets, and radar sites with different levels of risks. It can severely task all the resources (people, hardware, software) of the system trying to compute the possible routes. The nature of the problem can cause operational planning systems to take longer to generate a solution …

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A Visual Meta-Language For Generic Modeling, Hakan Canli Mar 2002

A Visual Meta-Language For Generic Modeling, Hakan Canli

Theses and Dissertations

This research examines the usefulness of a visual meta-language (VLGM Visual Language for Generic Modeling) developed for the specification of components and relations in a modeling domain. The language is designed to allow software tools to interpret specifications and automatically provide modeling environments. VLGM makes use of the object-orientated software engineering methodology. It defines four types of special classes and three types of relations between them. Data types and primitive types are allocated with several attributes to provide restrictions and enable consistency checks over models. As part of this research a software tool was designed. The tool provides a workspace …

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Ontological Engineering And Mapping In Multiagent Systems Development, Jonathan M. Dileo Mar 2002

Ontological Engineering And Mapping In Multiagent Systems Development, Jonathan M. Dileo

Theses and Dissertations

Multiagent systems have received much attention in recent years due to their advantages in complex, distributed environments. Previous work at the Air Force Institute of Technology has developed a methodology for analyzing, designing, and developing multiagent systems, called Multiagent Systems Engineering (MaSE). MaSE currently does not address the information domain of the system, which is an integral part of designing proper system execution. This research extends the MaSE methodology to include the use of ontologies for information domain specification. The extensions allow the designer to specify information flow by using objects from the ontology as parameters in agent conversations. The …

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Translation And Rotation Invariant Multiscale Image Registration, Jennifer L. Manfra Mar 2002

Translation And Rotation Invariant Multiscale Image Registration, Jennifer L. Manfra

Theses and Dissertations

The most recent research involved registering images in the presence of translations and rotations using one iteration of the redundant discrete wavelet transform. We extend this work by creating a new multiscale transform to register two images with translation or rotation differences, independent of scale differences between the images. Our two-dimensional multiscale transform uses an innovative combination of lowpass filtering and the continuous wavelet transform to mimic the two-dimensional redundant discrete wavelet transform. This allows us to obtain multiple subbands at various scales while maintaining the desirable properties of the redundant discrete wavelet transform. Whereas the discrete wavelet transform produces …

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Categorizing Network Attacks Using Pattern Classification Algorithms, George E. Noel Iii Mar 2002

Categorizing Network Attacks Using Pattern Classification Algorithms, George E. Noel Iii

Theses and Dissertations

The United States Air Force relies heavily on computer networks for many day-to-day activities. Many of these networks are affected by various types of attacks that can be launched from anywhere on the globe. The rising prominence of organizations such as the AFCERT and the MAJCOM NOSCs is evidence of an increasing realization among the Air Force leadership that protecting our computer networks is vitally important. A critical requirement for protecting our networks is the ability to detect attacks and intrusion attempts. This research is an effort to refine a portion of an AFIT-developed intrusion detection system known as the …

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Investigation Of Cooperative Behavior In Autonomous Wide Search Munitions, Robert E. Dunkel Iii Mar 2002

Investigation Of Cooperative Behavior In Autonomous Wide Search Munitions, Robert E. Dunkel Iii

Theses and Dissertations

The purpose of this research is to investigate the effectiveness of wide-area search munitions in various scenarios using different cooperative behavior algorithms. The general scenario involves multiple autonomous munitions searching for an unknown number of targets of different priority in unknown locations. Three cooperative behavior algorithms are used in each scenario: no cooperation, cooperative attack only, and cooperative classification and attack. In the cooperative cases, the munitions allocate tasks on-line as a group, using linear programming techniques to determine the optimum allocation. Each munition provides inputs to the task allocation routine in the form of probabilities of successfully being able …

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Application Of Information Retrieval Techniques To Heterogeneous Databases In The Virtual Distributed Laboratory, Rodney D. Lykins Mar 2002

Application Of Information Retrieval Techniques To Heterogeneous Databases In The Virtual Distributed Laboratory, Rodney D. Lykins

Theses and Dissertations

The Department of Defense (DoD) maintains thousands of Synthetic Aperture Radar (SAR), Infrared (IR), Hyper-Spectral intelligence imagery and Electro-Optical (EO) target signature data. These images are essential to evaluating and testing individual algorithm methodologies and development techniques within the Automatic Target Recognition (ATR) community. The Air Force Research Laboratory Sensors Directorate (AFRL/SN) has proposed the Virtual Distributed Laboratory (VDL) to maintain a central collection of the associated imagery metadata and a query mechanism to retrieve the desired imagery. All imagery metadata is stored in relational database format for access from agencies throughout the federal government and large civilian universities. Each …

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Mrpc: Maximizing Network Lifetime For Reliable Routing In Wireless Environments, Archan Misra, Suman Banerjee Mar 2002

Mrpc: Maximizing Network Lifetime For Reliable Routing In Wireless Environments, Archan Misra, Suman Banerjee

Research Collection School Of Computing and Information Systems

We propose MRPC, a new power-aware routing algorithm for energy-efficient routing that increases the operational lifetime of multi-hop wireless networks. In contrast to conventional power-aware algorithms, MRPC identifies the capacity of a node not just by its residual battery energy, but also by the expected energy spent in reliably forwarding a packet over a specific link. Such a formulation better captures scenarios where link transmission costs also depend on physical distances between nodes and the link error rates. Using a max-min formulation, MRPC selects the path that has the largest packet capacity at the 'critical' node (the one with the …

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B2b E-Commerce Revisited: Leading Perspectives On The Key Issues And Research Directions, Qizhi Dai, Robert J. Kauffman Mar 2002

B2b E-Commerce Revisited: Leading Perspectives On The Key Issues And Research Directions, Qizhi Dai, Robert J. Kauffman

Research Collection School Of Computing and Information Systems

The application of Internet technologies for the conduct of interfirm business transactions has given rise to a boom in business-to-business (B2B) electronic commerce. Yet, although there are many success stories that have been reported over the past several years, the progress of B2B e-commerce has been hindered by unanticipated technical, organizational, economic and legal challenges that diminish value. In this article, we report on a series of interviews with leading academic researchers and industry senior managers who are in a unique position to make sense of key issues and offer useful insights. The respondents provide their views on the efficacy …

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Ontology-Based Semantic Classification Of Unstructured Documents, Ching Kang Cheng, Xiao Shan Pan, Franz J. Kurfess Feb 2002

Ontology-Based Semantic Classification Of Unstructured Documents, Ching Kang Cheng, Xiao Shan Pan, Franz J. Kurfess

Computer Science and Software Engineering

As more and more knowledge and information becomes available through computers, a critical capability of systems supporting knowledge management is the classification of documents into categories that are meaningful to the user. In a step beyond the use of keywords, we developed a system that analyzes the sentences contained in unstructured or semi-structured documents, and utilizes an ontology reflecting the domain knowledge for a semantic classification of the documents. An experimental system has been implemented for the analysis of small documents in combination with a limited ontology; an extension to larger sets of documents and extended ontologies, together with an …

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Virtual Hierarchies - An Architecture For Building And Maintaining Efficient And Resilient Trust Chains, John Marchesini, Sean Smith Feb 2002

Virtual Hierarchies - An Architecture For Building And Maintaining Efficient And Resilient Trust Chains, John Marchesini, Sean Smith

Computer Science Technical Reports

In Public Key Infrastructure (PKI), the simple, monopolistic CA model works fine until we consider the real world. Then, issues such as scalability and mutually suspicious organizations create the need for a multiplicity of CAs, which immediately introduces the problem of how to organize them to balance resilience to compromise against efficiency of path discovery. However, security has given us tools such as secure coprocessing, secret splitting, secret sharing, and threshold cryptography for securely carrying out computations among multiple trust domains; distributed computing has given us peer-to-peer networking, for creating self-organizing distributed systems. In this paper, we use these latter …

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Trusted Paths For Browsers: An Open-Source Solution To Web Spoofing, Zishuang (Eileen) Ye, Sean Smith Feb 2002

Trusted Paths For Browsers: An Open-Source Solution To Web Spoofing, Zishuang (Eileen) Ye, Sean Smith

Computer Science Technical Reports

The security of the vast majority of ``secure'' Web services rests on SSL server PKI. However, this PKI doesn't work if the the adversary can trick the browser into appearing to tell the user the wrong thing about the certificates and cryptography. The seminal web spoofing work of Felten et al demonstrated the potential, in 1996, for malicious servers to impersonate honest servers. Our recent follow-up work explicitly shows how malicious servers can still do this---and can also forge the existence of an SSL session and the contents of the alleged server certificate. This paper reports the results of our …

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Test Case Prioritization: A Family Of Empirical Studies, Sebastian Elbaum, Alexey G. Malishevsky, Gregg Rothermel Feb 2002

Test Case Prioritization: A Family Of Empirical Studies, Sebastian Elbaum, Alexey G. Malishevsky, Gregg Rothermel

School of Computing: Faculty Publications

To reduce the cost of regression testing, software testers may prioritize their test cases so that those which are more important, by some measure, are run earlier in the regression testing process. One potential goal of such prioritization is to increase a test suite’s rate of fault detection. Previous work reported results of studies that showed that prioritization techniques can significantly improve rate of fault detection. Those studies, however, raised several additional questions: 1) Can prioritization techniques be effective when targeted at specific modified versions; 2) what trade-offs exist between fine granularity and coarse granularity prioritization techniques; 3) can the …

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