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Articles 1 - 9 of 9
Full-Text Articles in Physical Sciences and Mathematics
Modeling Heterogeneous User Churn And Local Resilience Of Unstructured P2p Networks, Zhongmei Yao, Derek Leonard, Dmitri Loguinov, Xiaoming Wang
Modeling Heterogeneous User Churn And Local Resilience Of Unstructured P2p Networks, Zhongmei Yao, Derek Leonard, Dmitri Loguinov, Xiaoming Wang
Computer Science Faculty Publications
Previous analytical results on the resilience of unstructured P2P systems have not explicitly modeled heterogeneity of user churn (i.e., difference in online behavior) or the impact of in-degree on system resilience. To overcome these limitations, we introduce a generic model of heterogeneous user churn, derive the distribution of the various metrics observed in prior experimental studies (e.g., lifetime distribution of joining users, joint distribution of session time of alive peers, and residual lifetime of a randomly selected user), derive several closed-form results on the transient behavior of in-degree, and eventually obtain the joint in/out degree isolation probability as a simple …
Effective Teaching Of Programming Concepts Using Low-Resolution (Character) Graphics, Tamisra Haran Sanyal
Effective Teaching Of Programming Concepts Using Low-Resolution (Character) Graphics, Tamisra Haran Sanyal
Computer Science Faculty Publications
For novice students of Computer Programming, the difference between Floating point numbers and Integers (and consequent difference between arithmetic operations on them) appears to be a difficult concept to grasp. In popular languages such as C++ or Java, this difficulty is made more acute by the fact that the same symbol is used for both floating point division and integer division.1 Without a proper grasp of the difference between these two fundamentally different kinds of numbers, students would also find it difficult to understand that floating point results should not be compared for equality. I was therefore interested in finding …
Interacting With Web Hierarchies, Saverio Perugini, Naren Ramakrishnan
Interacting With Web Hierarchies, Saverio Perugini, Naren Ramakrishnan
Computer Science Faculty Publications
Web site interfaces are a particularly good fit for hierarchies in the broadest sense of that idea, i.e. a classification with multiple attributes, not necessarily a tree structure. Several adaptive interface designs are emerging that support flexible navigation orders, exposing and exploring dependencies, and procedural information-seeking tasks. This paper provides a context and vocabulary for thinking about hierarchical Web sites and their design. The paper identifies three features that interface to information hierarchies. These are flexible navigation orders, the ability to expose and explore dependencies, and support for procedural tasks. A few examples of these features are also provided
Sound Source Localization And Separation, Biniyam Tesfaye Taddese
Sound Source Localization And Separation, Biniyam Tesfaye Taddese
Mathematics, Statistics, and Computer Science Honors Projects
People face the problem of sound source localization and separation in situations where they attempt to localize and focus on a source of sound among a dissonance of conversations and background noise. This paper synthesizes a sound source localization routine. We utilize a general source separation technique, Independent Component Analysis.. Particularly, basic ICA was applied to separate mixtures of low frequency, narrow band, non-Gaussian signals by using closely spaced uni-directional microphones. The localization routine worked with an average condition number of 10. The routine was tested on data collected in a laboratory.
Bluetooth Assassin: A Location-Based Game For Mobile Devices, Miao Wang, Brian Mac Namee
Bluetooth Assassin: A Location-Based Game For Mobile Devices, Miao Wang, Brian Mac Namee
Conference papers
This short paper will describe Bluetooth Assassin, a location-based game developed for mobile devices.
Realtime Query Expansion And Procedural Interfaces For Information Hierarchies, Saverio Perugini
Realtime Query Expansion And Procedural Interfaces For Information Hierarchies, Saverio Perugini
Computer Science Faculty Publications
We demonstrate the use of two user interfaces for interacting with web hierarchies. One uses the dependencies underlying a hierarchy to perform real-time query expansion and, in this way, acts as an in situ feedback mechanism. The other enables the user to cascade the output from one interaction to the input of another, and so on, and, in this way, supports procedural information-seeking tasks without disrupting the flow of interaction.
Information Assurance Through Binary Vulnerability Auditing, William B. Kimball, Saverio Perugini
Information Assurance Through Binary Vulnerability Auditing, William B. Kimball, Saverio Perugini
Computer Science Faculty Publications
The goal of this research is to develop improved methods of discovering vulnerabilities in software. A large volume of software, from the most frequently used programs on a desktop computer, such as web browsers, e-mail programs, and word processing applications, to mission-critical services for the space shuttle, is unintentionally vulnerable to attacks and thus insecure. By seeking to improve the identification of vulnerabilities in software, the security community can save the time and money necessary to restore compromised computer systems. In addition, this research is imperative to activities of national security such as counterterrorism. The current approach involves a systematic …
Ip's Problem Child: Shifting The Paradigms For Software Protection, Jacqueline D. Lipton
Ip's Problem Child: Shifting The Paradigms For Software Protection, Jacqueline D. Lipton
Articles
Computer software is somewhat of a problem child for intellectual property law. Courts and legislatures have struggled to encourage innovations in software development while, at the same time, attempting to avoid undesirable digital information monopolies. Neither the patent nor the copyright system has provided a particularly satisfactory paradigm for software protection. Although patents have received greater attention than copyrights in the software context (consider, for example, the recent BlackBerry case), copyright law arguably creates more insidious undercurrents in today's marketplace. This is partly because we have not yet appreciated the potential impact of recent developments in programming methodology and digital …
Coalgebras And Their Logics, Alexander Kurz
Coalgebras And Their Logics, Alexander Kurz
Engineering Faculty Articles and Research
"Transition systems pervade much of computer science. This article outlines the beginnings of a general theory of specification languages for transition systems. More specifically, transition systems are generalised to coalgebras. Specification languages together with their proof systems, in the following called (logical or modal) calculi, are presented by the associated classes of algebras (e.g., classical propositional logic by Boolean algebras). Stone duality will be used to relate the logics and their coalgebraic semantics."