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A Comparative Exploration Of Freebsd Bug Lifetimes, Gargi BOUGIE, Christoph TREUDE, Daniel M. GERMÁN, Margaret-Anne STOREY 2010 Singapore Management University

A Comparative Exploration Of Freebsd Bug Lifetimes, Gargi Bougie, Christoph Treude, Daniel M. Germán, Margaret-Anne Storey

Research Collection School Of Computing and Information Systems

In this paper, we explore the viability of mining the basic data provided in bug repositories to predict bug lifetimes. We follow the method of Lucas D. Panjer as described in his paper, Predicting Eclipse Bug Lifetimes. However, in place of Eclipse data, the FreeBSD bug repository is used. We compare the predictive accuracy of five different classification algorithms applied to the two data sets. In addition, we propose future work on whether there is a more informative way of classifying bugs than is considered by current bug tracking systems.


Online Layered File System (Olfs): A Layered And Versioned Filesystem And Performance Analysis, Joseph P. Kaylor, Konstantin Läufer, George K. Thiruvathukal 2010 Loyola University Chicago

Online Layered File System (Olfs): A Layered And Versioned Filesystem And Performance Analysis, Joseph P. Kaylor, Konstantin Läufer, George K. Thiruvathukal

Computer Science: Faculty Publications and Other Works

We present a novel form of intra-volume directory layering with hierarchical, inheritance-like namespace unification. While each layer of an OLFS volume constitutes a subvolume that can be mounted separately in a fan-in configuration, the entire hierarchy is always accessible (online) and fully navigable through any mounted layer. OLFS uses a relational database to store its layering metadata and either a relational database or any (virtual) host file system as its backing store, along with metadata and block caching for improved performance. Because OLFS runs as a virtual file system in user-space, its capabilities are available to all existing software without …


A Publish-Subscribe System For Data Replication And Synchronization Among Integrated Person-Centric Information Systems, Xiangbin Qiu 2010 Utah State University

A Publish-Subscribe System For Data Replication And Synchronization Among Integrated Person-Centric Information Systems, Xiangbin Qiu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Synchronization of data across an integrated system of heterogeneous databases is a difficult but important task, especially in the context of integrating health care information throughout a region, state, or nation. This thesis describes the design and implementation of a data replication and synchronization tool, called the Sync Engine, which allows users to define custom data-sharing patterns and transformations for an integrated system of heterogeneous person-centric databases. This thesis also discusses the relationship between the Sync Engine's contributions and several relevant issues in the area of data integration and replication. The Sync Engine's design and implementation was validated by …


Computer-Aided Detection Of Breast Cancer Using Ultrasound Images, Yanhui Guo 2010 Utah State University

Computer-Aided Detection Of Breast Cancer Using Ultrasound Images, Yanhui Guo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ultrasound imaging suffers from severe speckle noise. We propose a novel approach for speckle reduction using 2D homogeneity and directional average filters to remove speckle noise. We transform speckle noise into additive noise using a logarithm transformation. Texture information is employed to describe the speckle characteristics of the image. The homogeneity value is defined using texture information value, and the ultrasound image is transformed into a homogeneity domain from the gray domain. If the homogeneity value is high, the region is homogenous and has less speckle noise. Otherwise, the region is nonhomogenous, and speckle noise occurs. The threshold value is …


A Singular-Value-Based Semi-Fragile Watermarking Scheme For Image Content Authentication With Tampering Localization, Xing Xin 2010 Utah State University

A Singular-Value-Based Semi-Fragile Watermarking Scheme For Image Content Authentication With Tampering Localization, Xing Xin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents a novel singular-value-based semi-fragile watermarking scheme for image content authentication with tampering localization. The proposed scheme first generates a secured watermark bit sequence by performing a logical "xor" operation on a content-based watermark and content-independent watermark, wherein the content-based watermark is generated by a singular-value-based watermark bit sequence that represents intrinsic algebraic image properties, and the content-independent watermark is generated by a private-key-based random watermark bit sequence. It next embeds the secure watermark in the approximation subband of each non-overlapping 4×4 block using the adaptive quantization method to generate the watermarked image. The image content authentication process …


Generation And Analysis Of Verbal Route Directions For Blind Navigation, John Nicholson 2010 Utah State University

Generation And Analysis Of Verbal Route Directions For Blind Navigation, John Nicholson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

According to the National Federation of the Blind, there are an estimated 10 million people in the United States who are visually impaired. Of these, 1.3 million are legally blind. Many people with extreme vision loss receive orientation and mobility training in order to help them learn skills that allow them to travel and navigate multiple types of indoor and outdoor environments. Even with this training, a fundamental problem these people face is learning new routes, especially in environments with which they are not familiar. Although the research community has developed a number of localization and navigation aids that are …


Understanding The Scalability Of Bayesian Network Inference Using Clique Tree Growth Curves, Ole J. Mengshoel 2010 Carnegie Mellon University

Understanding The Scalability Of Bayesian Network Inference Using Clique Tree Growth Curves, Ole J. Mengshoel

Ole J Mengshoel

One of the main approaches to performing computation in Bayesian networks (BNs) is clique tree clustering and propagation. The clique tree approach consists of propagation in a clique tree compiled from a BN, and while it was introduced in the 1980s, there is still a lack of understanding of how clique tree computation time depends on variations in BN size and structure. In this article, we improve this understanding by developing an approach to characterizing clique tree growth as a function of parameters that can be computed in polynomial time from BNs, specifically: (i) the ratio of the number of …


Financial Time Series Forecasting With Machine Learning Techniques: A Survey, Bjoern Krollner, Bruce Vanstone, Gavin Finnie 2010 Bond University

Financial Time Series Forecasting With Machine Learning Techniques: A Survey, Bjoern Krollner, Bruce Vanstone, Gavin Finnie

Gavin Finnie

Stock index forecasting is vital for making informed investment decisions. This paper surveys recent literature in the domain of machine learning techniques and artificial intelligence used to forecast stock market movements. The publications are categorised according to the machine learning technique used, the forecasting timeframe, the input variables used, and the evaluation techniques employed. It is found that there is a consensus between researchers stressing the importance of stock index forecasting. Artificial Neural Networks (ANNs) are identified to be the dominant machine learning technique in this area. We conclude with possible future research directions.


Financial Time Series Forecasting With Machine Learning Techniques: A Survey, Bjoern Krollner, Bruce Vanstone, Gavin Finnie 2010 Bond University

Financial Time Series Forecasting With Machine Learning Techniques: A Survey, Bjoern Krollner, Bruce Vanstone, Gavin Finnie

Bjoern Krollner

Stock index forecasting is vital for making informed investment decisions. This paper surveys recent literature in the domain of machine learning techniques and artificial intelligence used to forecast stock market movements. The publications are categorised according to their research motivation, the machine learning technique used, the surveyed stock market, the forecasting time-frame, the input variables used, and the evaluation techniques employed. It is found that there is a consensus between researchers stressing the importance of stock index forecasting and that the results are promising. Artificial Neural Networks (ANNs) are identified to be the dominant machine learning technique in this area. …


A Hybrid Genetic Algorithm For The Student-Aware University Course Timetabling Problem, Ernesto Ferrer Queiros Nunez 2010 Macalester College

A Hybrid Genetic Algorithm For The Student-Aware University Course Timetabling Problem, Ernesto Ferrer Queiros Nunez

Mathematics, Statistics, and Computer Science Honors Projects

Traditionally, academic institutions schedule courses using constraints that ensure that instructors and courses do not overlap in available rooms and time periods; students' planning needs are rarely taken into account. This problem becomes particularly acute for students in liberal arts institutions, because they have multiple graduation requirements in addition to their chosen academic program. My research builds on the University Course Timetabling Problem (UCTP) to include students' scheduling needs. This approach to the UCTP problem uses a combination of a genetic algorithm and case-based reasoning.

To improve the performance of the genetic algorithm, I use a group-based genetic algorithm to …


Pre-Service Middle School Teachers’ Knowledge Of Algebraic Thinking, Marta Magiera, John Moyer, Leigh A. van den Kieboom 2010 Marquette University

Pre-Service Middle School Teachers’ Knowledge Of Algebraic Thinking, Marta Magiera, John Moyer, Leigh A. Van Den Kieboom

Mathematics, Statistics and Computer Science Faculty Research and Publications

In this study we examined the relationship between 18 pre-service middle school teachers’ own ability to use algebraic thinking to solve problems and their ability to recognize and interpret the algebraic thinking of middle school students. We assessed the pre-service teachers’ own algebraic thinking by examining their solutions and explanations to multiple algebra-based tasks posed during a semester-long mathematics content course. We assessed their ability to recognize and interpret the algebraic thinking of students in two ways. The first was by analyzing the preservice teachers’ ability to interpret students’ written solutions to open-ended algebra-based tasks. The second was by analyzing …


Pre-Service Teachers’ Knowledge Of Algebraic Thinking And The Characteristics Of The Questions Posed For Students, Leigh A. van den Kieboom, Marta Magiera, John Moyer 2010 Marquette University

Pre-Service Teachers’ Knowledge Of Algebraic Thinking And The Characteristics Of The Questions Posed For Students, Leigh A. Van Den Kieboom, Marta Magiera, John Moyer

Mathematics, Statistics and Computer Science Faculty Research and Publications

In this study, we explored the relationship between the strength of pre-service teachers’ algebraic thinking and the characteristics of the questions they posed during cognitive interviews that focused on probing the algebraic thinking of middle school students. We developed a performance rubric to evaluate the strength of pre-service teachers’ algebraic thinking across 130 algebra-based tasks. We used an existing coding scheme found in the literature to analyze the characteristics of the questions pre-service teachers posed during clinical interviews. We found that pre-service teachers with higher algebraic thinking abilities were able to pose probing questions that uncovered student thinking through the …


Financial Time Series Forecasting With Machine Learning Techniques: A Survey, Bjoern Krollner, Bruce Vanstone, Gavin Finnie 2010 Bond University

Financial Time Series Forecasting With Machine Learning Techniques: A Survey, Bjoern Krollner, Bruce Vanstone, Gavin Finnie

Bruce Vanstone

Stock index forecasting is vital for making informed investment decisions. This paper surveys recent literature in the domain of machine learning techniques and artificial intelligence used to forecast stock market movements. The publications are categorised according to the machine learning technique used, the forecasting timeframe, the input variables used, and the evaluation techniques employed. It is found that there is a consensus between researchers stressing the importance of stock index forecasting. Artificial Neural Networks (ANNs) are identified to be the dominant machine learning technique in this area. We conclude with possible future research directions.


Smap-Ws: A Parallel Web Service For Structural Proteome-Wide Ligand-Binding Site Comparison, Jingyuan Ren, Lei Xie, Wilfred W. Li, Philip E. Bourne 2010 San Diego Supercomputer Center

Smap-Ws: A Parallel Web Service For Structural Proteome-Wide Ligand-Binding Site Comparison, Jingyuan Ren, Lei Xie, Wilfred W. Li, Philip E. Bourne

Publications and Research

The proteome-wide characterization and analysis of protein ligand-binding sites and their interactions with ligands can provide pivotal information in understanding the structure, function and evolution of proteins and for designing safe and efficient therapeutics. The SMAP web service (SMAP-WS) meets this need through parallel computations designed for 3D ligand-binding site comparison and similarity searching on a structural proteome scale. SMAP-WS implements a shape descriptor (the Geometric Potential) that characterizes both local and global topological properties of the protein structure and which can be used to predict the likely ligand-binding pocket [Xie,L. and Bourne,P.E. (2007) A robust and efficient algorithm for …


A Peer-Tree Based Location Lookup Service In Mobile Wireless Networks, Jun Liu 2010 University of North Dakota

A Peer-Tree Based Location Lookup Service In Mobile Wireless Networks, Jun Liu

Computer Science Faculty Publications

We present a location look-up service for aiding location-based routing in wireless networks with mobile hosts. This location look up service is constructed based on a peer-tree indexing structure which represents the friendship relations among mobile hosts. The friendship is derived from the relations of sharing various-length common suffixes of host identifiers. A friendship relation determines the cooperation relation among mobile hosts. The Peer-Tree indexing structure provides a guideline for propagating location updates and queries in an organized manner. Each host periodically propagates its up-to-date location to a small number of its friends. Location queries are forwarded to and serviced …


Image Segmentation And Analysis For Automated Classification Of Traumatic Pelvic Injuries, Simina Vasilache 2010 Virginia Commonwealth University

Image Segmentation And Analysis For Automated Classification Of Traumatic Pelvic Injuries, Simina Vasilache

Theses and Dissertations

In the past decades, technical advances have allowed for the collection and storage of more types and larger quantities of medical data. The increase in the volume of existing medical data has increased the need for processing and analyzing such data. Medical data holds information that is invaluable for diagnostic as well as treatment planning purposes. Presently, a large portion of the data is not optimally used towards medical decisions because information contained in the data is inaccessible through simple human inspection, or traditional computational methods. In the field of trauma medicine, where caregivers are frequently confronted with situations where …


Leveraging Virtualization For Performance Driven Development, Matthew Sullivan 2010 Regis University

Leveraging Virtualization For Performance Driven Development, Matthew Sullivan

Regis University Student Publications (comprehensive collection)

This thesis contains the research component of a software engineering study to create a .NET application performance testing lab, and several guided learning activities intended to teach the fundamentals of how to use it. In arriving upon the research which serves as the groundwork for this project, an introduction to the concepts of software performance, the risks associated with performances, and an approach to mitigating this risks called "performance driven development" is presented. This introduction is expanded by an overview of how performance is affected from application, network, database and presentation aspects. To address problems associated with performance in .NET …


Memristics: Memristors, Again? – Part Ii, How To Transform Wired ‘Translations’ Between Crossbars Into Interactions?, Rudolf Kaehr 2010 ThinkArt Lab Glasgow

Memristics: Memristors, Again? – Part Ii, How To Transform Wired ‘Translations’ Between Crossbars Into Interactions?, Rudolf Kaehr

Rudolf Kaehr

The idea behind this patchwork of conceptual interventions is to show the possibility of a “buffer-free” modeling of the crossbar architecture for memristive systems on the base of a purely difference-theoretical approach. It is considered that on a nano-electronic level principles of interpretation appears as mechanisms of complementarity. The most basic conceptual approach to such a complementarity is introduced as an interchangeability of operators and operands of an operation. Therefore, the architecture of crossbars gets an interpretation as complementarity between crossbar functionality and “buffering” translation functionality. That is, the same matter functions as operator and at once, as operand – …


Fundamental Work Toward An Image Processing-Empowered Dental Intelligent Educational System, Grace Olsen 2010 Virginia Commonwealth University

Fundamental Work Toward An Image Processing-Empowered Dental Intelligent Educational System, Grace Olsen

Theses and Dissertations

Computer-aided education in dental schools is greatly needed in order to reduce the need for human instructors to provide guidance and feedback as students practice dental procedures. A portable computer-aided educational system with advanced digital image processing capabilities would be less expensive than current computer-aided dental educational systems and would also address some of their limitations. This dissertation outlines the development of novel components that would be part of such a system. This research includes the design of a novel image processing technique, the Directed Active Shape Model algorithm, which is used to locate the tooth and drilled preparation from …


Testing And Maintenance In The Video Game Industry Today, Anthony A. Jarman 2010 Liberty University

Testing And Maintenance In The Video Game Industry Today, Anthony A. Jarman

Senior Honors Theses

Testing and maintenance are important when designing any type of software, especially video games. Since the gaming industry began, testing and maintenance techniques have evolved and changed. In order to understand how testing and maintenance techniques are practiced in the gaming industry, several key elements must be examined. First, specific testing and maintenance techniques that are most useful for video games must be analyzed to understand their effectiveness. Second, the processes used for testing and maintaining video games at the beginning of the industry must be reviewed in order to see how far testing and maintenance techniques have progressed. Third, …


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