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The Fat-Pyramid: A Robust Network For Parallel Computation, Ronald I. Greenberg Jan 2018

The Fat-Pyramid: A Robust Network For Parallel Computation, Ronald I. Greenberg

Ronald Greenberg

This paper shows that a fat-pyramid of area Theta(A) built from processors of size lg A requires only O(lg^2 A) slowdown in bit-times to simulate any network of area A under very general conditions. Specifically, there is no restriction on processor size (amount of attached memory) or number of processors in the competing network, nor is the assumption of unit wire delay required. This paper also derives upper bounds on the slowdown required by a fat-pyramid to simulate a network of larger area in the case of unit wire delay.


The Fat-Pyramid And Universal Parallel Computation Independent Of Wire Delay, Ronald I. Greenberg Jan 2018

The Fat-Pyramid And Universal Parallel Computation Independent Of Wire Delay, Ronald I. Greenberg

Ronald Greenberg

This paper shows that a fat-pyramid of area Θ(A) requires only O(log A) slowdown to simulate any competing network of area A under very general conditions. The result holds regardless of the processor size (amount of attached memory) and number of processors in the competing networks as long as the limitation on total area is met. Furthermore, the result is valid regardless of the relationship between wire length and wire delay. We especially focus on elimination of the common simplifying assumption that unit time suffices to traverse a wire regardless of its length, since the assumption becomes more and more …


Minimizing Channel Density With Movable Terminals, Ronald I. Greenberg, Jau-Der Shih Jan 2018

Minimizing Channel Density With Movable Terminals, Ronald I. Greenberg, Jau-Der Shih

Ronald Greenberg

We give algorithms to minimize density for channels with terminals that are movable subject to certain constraints. The main cases considered are channels with linear order constraints, channels with linear order constraints and separation constraints, channels with movable modules containing fixed terminals, and channels with movable modules and terminals. In each case, previous results for running time and space are improved by a factor of L/lg n and L , respectively, where L is the channel length and n is the number of terminals.


Packet Routing In Networks With Long Wires, Ronald I. Greenberg, Hyeong-Cheol Oh Jan 2018

Packet Routing In Networks With Long Wires, Ronald I. Greenberg, Hyeong-Cheol Oh

Ronald Greenberg

In this paper, we examine the packet routing problem for networks with wires of differing length. We consider this problem in a network independent context, in which routing time is expressed in terms of "congestion" and "dilation" measures for a set of packet paths. We give, for any constant ϵ > 0, a randomized on-line algorithm for routing any set of Npackets in O((C lgϵ(Nd) + D lg(Nd))/lg lg(Nd)) time, where C is the maximum congestion and D is the length of the longest path, both taking wire delays into …


Finding Connected Components On A Scan Line Array Processor, Ronald I. Greenberg Jan 2018

Finding Connected Components On A Scan Line Array Processor, Ronald I. Greenberg

Ronald Greenberg

This paper provides a new approach to labeling the connected components of an n x n image on a scan line array processor (comprised of n processing elements). Variations of this approach yield an algorithm guaranteed to complete in o(n lg n) time as well as algorithms likely to approach O(n) time for all or most images. The best previous solutions require using a more complicated architecture or require Omega(n lg n) time. We also show that on a restricted version of the architecture, any algorithm requires Omega(n lg n) time in the worst case.


Feasible Offset And Optimal Offset For Single-Layer Channel Routing, Ronald I. Greenberg, Jau-Der Shih Jan 2018

Feasible Offset And Optimal Offset For Single-Layer Channel Routing, Ronald I. Greenberg, Jau-Der Shih

Ronald Greenberg

The paper provides an efficient method to find all feasible offsets for a given separation in a VLSI channel routing problem in one layer. The prior literature considers this task only for problems with no single-sided nets. When single-sided nets are included, the worst-case solution time increases from Theta(n) to Omega(n^2), where n is the number of nets. But, if the number of columns c is O(n), one can solve the problem in time O(n^{1.5}lg n ), which improves upon a `naive' O(cn) approach. As a corollary of this result, the same time bound suffices to find the optimal offset …


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, …


Design And Implementation Of Triveni: A Process-Algebraic Api For Threads + Events, Christopher P. Colby, Lalita Jategaonkar Jagaeesan, Radhakrishnan Jagadeesan, Konstantin Laufer, Carlos Puchol Oct 2017

Design And Implementation Of Triveni: A Process-Algebraic Api For Threads + Events, Christopher P. Colby, Lalita Jategaonkar Jagaeesan, Radhakrishnan Jagadeesan, Konstantin Laufer, Carlos Puchol

Konstantin Läufer

We describe Triveni, a framework and API for integrating threads and events. The design of Triveni is based on an algebra, including preemption combinators, of processes. Triveni is compatible with existing threads standards, such as Pthreads and Java threads, and with the event models structured on the Observer pattern. We describe the software architecture and algorithms underlying a concrete implementation of Triveni in Java. This environment includes specification based testing of safety properties. The results described in the paper have been used to integrate process-algebraic methods into (concurrent) object orientated programming.


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.


Putting Type Annotations To Work, Martin Odersky, Konstantin Laufer Oct 2017

Putting Type Annotations To Work, Martin Odersky, Konstantin Laufer

Konstantin Läufer

We study an extension of the Hindley/Milner system with explicit type scheme annotations and type declarations. The system can express polymorphic function arguments, user-defined data types with abstract components, and structure types with polymorphic fields. More generally, all programs of the polymorphic lambda calculus can be encoded by a translation between typing derivations. We show that type reconstruction in this system can be reduced to the decidable problem of first-order unification under a mixed prefix.


Guest Editors' Introduction: Best Of Respect, Part 2, Tiffany Barnes, Jamie Payton, George K. Thiruvathukal, Jeff Forbes, Kristy Elizabeth Boyer Jan 2017

Guest Editors' Introduction: Best Of Respect, Part 2, Tiffany Barnes, Jamie Payton, George K. Thiruvathukal, Jeff Forbes, Kristy Elizabeth Boyer

George K. Thiruvathukal

The guest editors introduce best papers on broadening participation in computing from the RESPECT'15 conference. The five articles presented here are part two of a two-part series representing research on broadening participation in computing. These articles study participation in intersectional ways, through the perceptions and experiences of African-American middle school girls, the sense of belonging in computing for LGBTQ students, the impact of a STEM scholarship and community development program for low-income and first-generation college students, a leadership development program, and how African-American women individually take leadership to enable their success in computing.


The Need For Research In Broadening Participation, Tiffany Barnes, George K. Thiruvathukal Jan 2017

The Need For Research In Broadening Participation, Tiffany Barnes, George K. Thiruvathukal

George K. Thiruvathukal

Underrepresentation in computing is a global problem, marked by a disturbing lack of access to computing resources and education among people underrepresented by race, ethnicity, gender, income, disability, and sexual-orientation status. It is urgent that we address this divide between those with and without the knowledge to create computational artifacts or even basic functional literacy. Important alliances for broadening participation (BP) are catalyzing efforts to engage more people in computing, but they are not enough. We need solid research as well.


The Myhill Functor, Input-Reduced Machines, And Generalised Krohn-Rhodes Theory, Robert H. Yacobellis Jan 2016

The Myhill Functor, Input-Reduced Machines, And Generalised Krohn-Rhodes Theory, Robert H. Yacobellis

Robert H Yacobellis

No abstract provided.


Preparing Computer Science Graduates For The 21st Century, Paul Parsons Sep 2015

Preparing Computer Science Graduates For The 21st Century, Paul Parsons

Paul Parsons

The nature of computer use has changed remarkably in the past fifty years. However, most undergraduate computer science courses are still often taught through an old paradigm that is not adequate to address modern concerns. This 90 minute seminar will address some issues relevant to preparing computer scientists for the 21st century. These include issues central to human-computer interaction (HCI) such as cognitive and perceptual aspects of computer users, ergonomics, and human factors. Although there has been literature on this topic for at least the past 15 years, it is still not widely recognized nor understood by the majority of …


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 …


Legal Issues: Security And Privacy With Mobile Devices, Brian Leonard, Maurice Dawson Dec 2014

Legal Issues: Security And Privacy With Mobile Devices, Brian Leonard, Maurice Dawson

Maurice Dawson

Privacy and security are two items being woven into the fabric of American law concerning mobile devices. This chapter will review and analyze the associated laws and policies that are currently in place or have been proposed to ensure proper execution of security measures for mobile and other devices while still protecting individual privacy. This chapter will address the fact that as the American society significantly uses mobile devices, it is imperative to understand the legal actions surrounding these technologies to include their associated uses. This chapter will also address the fact that with 9/11 in the not so distant …


A Model Of Data Structures Commonly Used In Programming Languages And Data Base Management Systems, William L. Honig Jul 2013

A Model Of Data Structures Commonly Used In Programming Languages And Data Base Management Systems, William L. Honig

William L Honig

This thesis claims that contemporary data structures can be understood and studied with an intelligible model which captures their essential differences and similarities and, further, that such a model is an appropriate basis for a top-down description method for data structures. To define the scope of the model, the data structures included in 21 programming languages and data base management systems have been tabulated. Each individual data structure is illustrated with an example drawn from a published paper or a working computer program. This mélange of data structures is divided into three classes (aggregates, associations , and files) and each …


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, …


Library Impact Statement For Csc 423 Network Intrusion Detection And Defense, Amanda Izenstark Nov 2012

Library Impact Statement For Csc 423 Network Intrusion Detection And Defense, Amanda Izenstark

Amanda Izenstark

Library Impact Statement in response to new course proposal for CSC 423 Network Intrusion Detection and Defense. New course was supported with no need for additional resources.


Library Impact Statement For Csc 523 Advanced Intrusion Detection And Defense, Amanda Izenstark Nov 2012

Library Impact Statement For Csc 523 Advanced Intrusion Detection And Defense, Amanda Izenstark

Amanda Izenstark

Library Impact Statement for CSC 523 Advanced Intrusion Detection and Defense. No new library resources are required to support this course.


Library Impact Statement For Csc 424 Live Forensics And Incident Response, Amanda Izenstark Nov 2012

Library Impact Statement For Csc 424 Live Forensics And Incident Response, Amanda Izenstark

Amanda Izenstark

Library Impact Statement in response to new course proposal for CSC 424 Live Forensics and Incident Response. New course was supported with no need for additional resources.


A Multi-Platform Application Suite For Enhancing South Asian Language Pedagogy, Tao Bai, Christopher K. Chung, Konstantin Läufer, Daisy Rockwell, George K. Thiruvathukal Jan 2012

A Multi-Platform Application Suite For Enhancing South Asian Language Pedagogy, Tao Bai, Christopher K. Chung, Konstantin Läufer, Daisy Rockwell, George K. Thiruvathukal

Konstantin Läufer

This interdisciplinary project explores the potential for handheld/wireless (H/W) technology in the context of language education within and beyond the classroom. Specifically, we have designed and implemented a suite of multi-platform (desktop/laptop, handheld, and browser) applications to enhance the teaching of South Asian languages such as Hindi-Urdu. Such languages are very difficult to learn, let alone write, and H/W devices (with their handwriting/drawing capabilities) can play a significant role in overcoming the learning curve. The initial application suite includes a character/word tracer, a word splitter/joiner, a smart flashcard with audio, contextual augmented stories for reading comprehension, and a poetic metronome. …


Enhancing The Cs Curriculum With With Aspect-Oriented Software Development (Aosd) And Early Experience, Konstantin Läufer, George K. Thiruvathukal, Tzilla Elrad Jan 2012

Enhancing The Cs Curriculum With With Aspect-Oriented Software Development (Aosd) And Early Experience, Konstantin Läufer, George K. Thiruvathukal, Tzilla Elrad

Konstantin Läufer

Aspect-oriented software development (AOSD) is evolving as an important step beyond existing software development approaches such as object-oriented development. An aspect is a module that captures a crosscutting concern, behavior that cuts across different units of abstraction in a software application; expressed as a module, such behavior can be enabled and disabled transparently and non-invasively, without changing the application code itself. Increasing industry demand for expertise in AOSD gives rise to the pedagogical challenge of covering this methodology and its foundations in the computer science curriculum. We present our curricular initiative to incorporate a novel course in AOSD in the …


A Model-Driven Approach To Job/Task Composition In Cluster Computing, Yogesh Kanitkar, Konstantin Läufer, Neeraj Mehta, George K. Thiruvathukal Jan 2012

A Model-Driven Approach To Job/Task Composition In Cluster Computing, Yogesh Kanitkar, Konstantin Läufer, Neeraj Mehta, George K. Thiruvathukal

Konstantin Läufer

In the general area of high-performance computing, object-oriented methods have gone largely unnoticed. In contrast, the Computational Neighborhood (CN), a framework for parallel and distributed computing with a focus on cluster computing, was designed from ground up to be object-oriented. This paper describes how we have successfully used UML in the following model-driven, generative approach to job/task composition in CN. We model CN jobs using activity diagrams in any modeling tool with support for XMI, an XML-based external representation of UML models. We then export the activity diagrams and use our XSLT-based tool to transform the resulting XMI representation to …


Natural Xml For Data Binding, Processing, And Persistence, George K. Thiruvathukal, Konstantin Läufer Jan 2012

Natural Xml For Data Binding, Processing, And Persistence, George K. Thiruvathukal, Konstantin Läufer

Konstantin Läufer

The article explains what you need to do to incorporate XML directly into your computational science application. The exploration involves the use of a standard parser to automatically build object trees entirely from application-specific classes. This discussion very much focuses on object-oriented programming languages such as Java and Python, but it can work for non-object-oriented languages as well. The ideas in the article provide a glimpse into the Natural XML research project.


Combining Soa And Bpm Technologies For Cross-System Process Automation, Sebastian Herr, John Shafaee, Konstantin Läufer, George K. Thiruvathukal, Guido Wirtz Jan 2012

Combining Soa And Bpm Technologies For Cross-System Process Automation, Sebastian Herr, John Shafaee, Konstantin Läufer, George K. Thiruvathukal, Guido Wirtz

Konstantin Läufer

This paper summarizes the results of an industry case study that introduced a cross-system business process automation solution based on a combination of SOA and BPM standard technologies (i.e., BPMN, BPEL, WSDL). Besides discussing major weaknesses of the existing, custom-built, solution and comparing them against experiences with the developed prototype, the paper presents a course of action for transforming the current solution into the proposed solution. This includes a general approach, consisting of four distinct steps, as well as specific action items that are to be performed for every step. The discussion also covers language and tool support and challenges …


The Extreme Software Development Series: An Open Curricular Framework For Applied Capstone Courses, Konstantin Läufer, George K. Thiruvathukal Jan 2012

The Extreme Software Development Series: An Open Curricular Framework For Applied Capstone Courses, Konstantin Läufer, George K. Thiruvathukal

Konstantin Läufer

We describe an open, flexible curricular framework for offering a collection of advanced undergraduate and graduate courses in software development. The courses offered within this framework are further unified by combining solid foundations with current technology and play the role of capstone courses in a modern software development track. Our initiative has been very successful with all stakeholders involved.