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Full-Text Articles in Physical Sciences and Mathematics

Building Capable, Energy-Efficient, Flexible Visualization And Sensing Clusters From Commodity Tablets, Thomas Delgado Dias, Xian Yan, Konstantin Läufer, George K. Thiruvathukal Oct 2017

Building Capable, Energy-Efficient, Flexible Visualization And Sensing Clusters From Commodity Tablets, Thomas Delgado Dias, Xian Yan, Konstantin Läufer, George K. Thiruvathukal

Konstantin Läufer

We explore the application of clusters of commodity tablet devices to problems spanning a “trilogy” of concerns: visualization, sensing, and computation. We conjecture that such clusters provide a low-cost, energy-efficient, flexible, and ultimately effective platform to tackle a wide range of problems within this trilogy. This is a work in progress, and we now elaborate our position and give a preliminary status report. A wide range of Android tablet devices are available in terms of price and capabilities. “You get what you pay for” w.r.t. display resolution, sensors, and chipset---corresponding to the trilogy. $200 gets one a 1280x800-pixel touch display, …


Network Technologies Used To Aggregate Environmental Data, Paul Stasiuk, Konstantin Läufer, George K. Thiruvathukal Oct 2017

Network Technologies Used To Aggregate Environmental Data, Paul Stasiuk, Konstantin Läufer, George K. Thiruvathukal

Konstantin Läufer

The goal of the Loyola Weather Service (lws) project is to design and build a system of functioning environmental monitoring widgets that can intelligently and autonomously control the environment around them based on set thresholds and triggers. The widgets will also have the ability to aggregate their data and easily display this data in various ways: through a user interface in the room that the widget is placed, via a web application, and programmatically via a RESTful web service.


Residual-Based Measurement Of Peer And Link Lifetimes In Gnutella Networks, Xiaoming Wang, Zhongmei Yao, Dmitri Loguinov Jan 2015

Residual-Based Measurement Of Peer And Link Lifetimes In Gnutella Networks, Xiaoming Wang, Zhongmei Yao, Dmitri Loguinov

Zhongmei Yao

Existing methods of measuring lifetimes in P2P systems usually rely on the so-called create-based method (CBM), which divides a given observation window into two halves and samples users "created" in the first half every Delta time units until they die or the observation period ends. Despite its frequent use, this approach has no rigorous accuracy or overhead analysis in the literature. To shed more light on its performance, we flrst derive a model for CBM and show that small window size or large Delta may lead to highly inaccurate lifetime distributions. We then show that create-based sampling exhibits an inherent …


On Node Isolation Under Churn In Unstructured P2p Networks With Heavy-Tailed Lifetimes, Zhongmei Yao, Xiaoming Wang, Dmitri Loguinov Jan 2015

On Node Isolation Under Churn In Unstructured P2p Networks With Heavy-Tailed Lifetimes, Zhongmei Yao, Xiaoming Wang, Dmitri Loguinov

Zhongmei Yao

Previous analytical studies [12], [18] of unstructured P2P resilience have assumed exponential user lifetimes and only considered age-independent neighbor replacement. In this paper, we overcome these limitations by introducing a general node-isolation model for heavy-tailed user lifetimes and arbitrary neighbor-selection algorithms. Using this model, we analyze two age-biased neighbor-selection strategies and show that they significantly improve the residual lifetimes of chosen users, which dramatically reduces the probability of user isolation and graph partitioning compared to uniform selection of neighbors. In fact, the second strategy based on random walks on age-weighted graphs demonstrates that for lifetimes with infinite variance, the system …


Modeling Heterogeneous User Churn And Local Resilience Of Unstructured P2p Networks, Zhongmei Yao, Derek Leonard, Dmitri Loguinov, Xiaoming Wang Jan 2015

Modeling Heterogeneous User Churn And Local Resilience Of Unstructured P2p Networks, Zhongmei Yao, Derek Leonard, Dmitri Loguinov, Xiaoming Wang

Zhongmei Yao

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 …


Network Technologies Used To Aggregate Environmental Data, Paul Stasiuk, Konstantin Läufer, George K. Thiruvathukal Jul 2013

Network Technologies Used To Aggregate Environmental Data, Paul Stasiuk, Konstantin Läufer, George K. Thiruvathukal

George K. Thiruvathukal

The goal of the Loyola Weather Service (lws) project is to design and build a system of functioning environmental monitoring widgets that can intelligently and autonomously control the environment around them based on set thresholds and triggers. The widgets will also have the ability to aggregate their data and easily display this data in various ways: through a user interface in the room that the widget is placed, via a web application, and programmatically via a RESTful web service.


Building Capable, Energy-Efficient, Flexible Visualization And Sensing Clusters From Commodity Tablets, Thomas Delgado Dias, Xian Yan, Konstantin Läufer, George K. Thiruvathukal Jul 2013

Building Capable, Energy-Efficient, Flexible Visualization And Sensing Clusters From Commodity Tablets, Thomas Delgado Dias, Xian Yan, Konstantin Läufer, George K. Thiruvathukal

George K. Thiruvathukal

We explore the application of clusters of commodity tablet devices to problems spanning a “trilogy” of concerns: visualization, sensing, and computation. We conjecture that such clusters provide a low-cost, energy-efficient, flexible, and ultimately effective platform to tackle a wide range of problems within this trilogy. This is a work in progress, and we now elaborate our position and give a preliminary status report. A wide range of Android tablet devices are available in terms of price and capabilities. “You get what you pay for” w.r.t. display resolution, sensors, and chipset---corresponding to the trilogy. $200 gets one a 1280x800-pixel touch display, …


High-Performance Java Platform Computing, Thomas W. Christopher, George K. Thiruvathukal Nov 2011

High-Performance Java Platform Computing, Thomas W. Christopher, George K. Thiruvathukal

George K. Thiruvathukal

Threading and concurrency are crucial to building high-performance Java applications -- but they have a reputation for complexity. High Performance Java Computing thoroughly demystifies these advanced development techniques. It delivers practical programming solutions, proven design patterns, and a rigorously-tested code library -- everything developers need to build optimized Java software for technical, business, and E-commerce applications. Start by understanding how threading and concurrency can be used to solve a wide variety of performance problems, enabling the construction of more powerful networked applications. Master the Java 2 Threads classes, including daemon threads, thread control, scheduling, and more. Review the key problems …


Utilization Of E-Learning Tools, Virtual Machines, & Open Source Software To Enhance Graduate Systems Engineering Programs, Maurice Dawson, Darrell Burrell, William Emanuel Dec 2010

Utilization Of E-Learning Tools, Virtual Machines, & Open Source Software To Enhance Graduate Systems Engineering Programs, Maurice Dawson, Darrell Burrell, William Emanuel

Maurice Dawson

This paper is a report on the findings of a study conducted on a graduate systems engineering course at an urban university in a group learning environment. The course, IEGR 501 Introduction to Advanced Systems Engineering, was a sixteen week course which took students with backgrounds in Industrial Engineering, Electrical Engineering, and Mechanical Engineering and prepared them to understand the systems engineering subject matter more. As the future of education becomes more and more virtual it becomes essential that universities take full advantage of the available tools at their disposal.


Understanding The Need And Importance Of The Cloud Computing Environment Within The National Institute Of Food And Agriculture, An Agency Of The United States Department Of Agriculture, Festus Onyegbula, Maurice Dawson, Jeffrey Stevens Dec 2010

Understanding The Need And Importance Of The Cloud Computing Environment Within The National Institute Of Food And Agriculture, An Agency Of The United States Department Of Agriculture, Festus Onyegbula, Maurice Dawson, Jeffrey Stevens

Maurice Dawson

Aligning information systems to corporate goals has emerged as a leading concern over the last couple of decades. It is essential that we understand the need for cloud computing and how this technology can be implemented. Through this literature review we review theories of cloud computing and further elaborate on the theoretical framework for the implementation of cloud computing technology across organizations. We also detail cloud computing implementations across various governmental organizations and also across the industry. This review is expected to provide the current study with a more practical perspective on the issues and complexities of using cloud computing …