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Computer Engineering Commons

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2015

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Articles 271 - 291 of 291

Full-Text Articles in Computer Engineering

An Analysis Of The Impact Of Playout Delay Adjustments Introduced By Voip Jitter Buffers On Listening Speech Quality, Peter Počta, Hugh Melvin, Andrew Hines Jan 2015

An Analysis Of The Impact Of Playout Delay Adjustments Introduced By Voip Jitter Buffers On Listening Speech Quality, Peter Počta, Hugh Melvin, Andrew Hines

Articles

This paper investigates the impact of frequent and small playout delay adjustments (time-shifting) of 30 ms or less introduced to silence periods by Voice over IP (VoIP) jitter buffer strategies on listening quality perceived by the end user. In particular, the quality impact is assessed using both a subjective method (quality scores obtained from subjective listening test) and an objective method based on perceptual modelling. Two different objective methods are used, PESQ (Perceptual Evaluation of Speech Quality, ITU-T Recommendation P.862) and POLQA (Perceptual Objective Listening Quality Assessment, ITU-T Recommendation P.863). Moreover, the relative accuracy of both objective models is assessed …


How Design Quality Improves With Increasing Computational Abilities: General Formulas And Case Study Of Aircraft Fuel Efficiency, Joe Lorkowski, Olga Kosheleva, Vladik Kreinovich, Sergei Soloviev Jan 2015

How Design Quality Improves With Increasing Computational Abilities: General Formulas And Case Study Of Aircraft Fuel Efficiency, Joe Lorkowski, Olga Kosheleva, Vladik Kreinovich, Sergei Soloviev

Departmental Technical Reports (CS)

It is known that the problems of optimal design are NP-hard -- meaning that, in general, a feasible algorithm can only produce close-to-optimal designs. The more computations we perform, the better design we can produce. In this paper, we theoretically derive quantitative formulas describing how the design qualities improves with the increasing computational abilities. We then empirically confirm the resulting theoretical formula by applying it to the problem of aircraft fuel efficiency.


Forensic Analysis Of A Sony Playstation 4: A First Look, Matthew Davies, Huw Read, Konstantinos Xynos, Iain Sutherland Jan 2015

Forensic Analysis Of A Sony Playstation 4: A First Look, Matthew Davies, Huw Read, Konstantinos Xynos, Iain Sutherland

Research outputs 2014 to 2021

The primary function of a games console is that of an entertainment system. However the latest iteration of these consoles has added a number of new interactive features that may prove of value to the digital investigator. This paper highlights the value of these consoles, in particular Sony's latest version of their PlayStation. This console provides a number of features including web browsing, downloading of material and chat functionality; all communication features that will be of interest to forensic investigators. In this paper we undertake an initial investigation of the PlayStation 4 games console. This paper identifies potential information sources …


Sheep Updates 2015 - Ravensthorpe, Bruce Mullan, Kate Pritchett, Kimbal Curtis, Chris Wilcox, Mike Hyder, Leigh Sonnerman, Lynne Bradshaw, Geoff Lindon, Katherine Davies, Joe Young, Stephen Lee, Ian Robertson, Lucy Anderton, Hayley Norman, Ed Barrett-Lenard, Jackie Jarvis, Ben Patrick Jan 2015

Sheep Updates 2015 - Ravensthorpe, Bruce Mullan, Kate Pritchett, Kimbal Curtis, Chris Wilcox, Mike Hyder, Leigh Sonnerman, Lynne Bradshaw, Geoff Lindon, Katherine Davies, Joe Young, Stephen Lee, Ian Robertson, Lucy Anderton, Hayley Norman, Ed Barrett-Lenard, Jackie Jarvis, Ben Patrick

Sheep Updates

This session covers fourteen papers from different authors:

1. The Sheep Industry Business Innovation project, Bruce Mullan, Sheep Industry Development Director, Department of Agriculture and Food, Western Australia

2. Western Australian sheep stocktake, Kate Pritchett and Kimbal Curtis, Research Officers, Department of Agriculture and Food, Western Australia

3. Wool demand and supply - short term volatility, long term opportunities, Chris Wilcox, Principal of Poimena Analysis

4. Lifetime management for maternal ewes, Mike Hyder, Research Officer, Department of Agriculture and Food, Western Australia

5. National Livestock Identification System (NLIS) for sheep and goats - what is the NLIS database? Leigh Sonnermann, …


College Of Engineering And Computing Graduate Catalog, Nova Southeastern University Jan 2015

College Of Engineering And Computing Graduate Catalog, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.


Coalgebraic Semantics Of Reflexive Economics (Dagstuhl Seminar 15042), Samson Abramsky, Alexander Kurz, Pierre Lescanne, Viktor Winschel Jan 2015

Coalgebraic Semantics Of Reflexive Economics (Dagstuhl Seminar 15042), Samson Abramsky, Alexander Kurz, Pierre Lescanne, Viktor Winschel

Engineering Faculty Articles and Research

This report documents the program and the outcomes of Dagstuhl Seminar 15042 “Coalgebraic Semantics of Reflexive Economics”.


Modular Timing Constraints For Delay-Insensitive Systems, Hoon Park, Anping He, Marly Roncken, Xiaoyu Song, Ivan Sutherland Jan 2015

Modular Timing Constraints For Delay-Insensitive Systems, Hoon Park, Anping He, Marly Roncken, Xiaoyu Song, Ivan Sutherland

Electrical and Computer Engineering Faculty Publications and Presentations

This paper introduces ARCtimer, a framework for modeling, generating, verifying, and enforcing timing constraints for individual self-timed handshake components. The constraints guarantee that the component’s gate-level circuit implementation obeys the component’s handshake protocol specification. Because the handshake protocols are delayinsensitive, self-timed systems built using ARCtimer-verified components are also delay-insensitive. By carefully considering time locally, we can ignore time globally. ARCtimer comes early in the design process as part of building a library of verified components for later system use. The library also stores static timing analysis (STA) code to validate and enforce the component’s constraints in any self-timed system built …


Creating A National Nonmotorized Traffic Count Archive: Process And Progress, Krista Nordback, Kristin A. Tufte, Morgan Harvey, Nathan Mcneil, Elizabeth Stolz, Jolene Liu Jan 2015

Creating A National Nonmotorized Traffic Count Archive: Process And Progress, Krista Nordback, Kristin A. Tufte, Morgan Harvey, Nathan Mcneil, Elizabeth Stolz, Jolene Liu

Civil and Environmental Engineering Faculty Publications and Presentations

Robust bicycle and pedestrian data on a national scale would help promote effective planning and engineering of walking and bicycling facilities, build the evidence-based case for funding such projects, and dispel notions that walking and cycling are not occurring. To organize and promote the collection of nonmotorized traffic data, a team of transportation professionals and computer scientists is creating a national bicycle and pedestrian count archive. This archive will enable data sharing by centralizing continuous and short-duration traffic counts in a publicly available online archive. Although other archives exist, this will be the first archive that will be national in …


Evolution And Usage Of The Portal Data Archive: 10-Year Retrospective, Kristin A. Tufte, Robert Bertini, Morgan Harvey Jan 2015

Evolution And Usage Of The Portal Data Archive: 10-Year Retrospective, Kristin A. Tufte, Robert Bertini, Morgan Harvey

Civil and Environmental Engineering Faculty Publications and Presentations

The Portal transportation data archive (http://portal.its.pdx.edu/) was begun in June 2004 in collaboration with the Oregon Department of Transportation, with a single data source: freeway loop detector data. In 10 years, Portal has grown to contain approximately 3 TB of transportation-related data from a wide variety of systems and sources, including freeway data, arterial signal data, travel times from Bluetooth detection systems, transit data, and bicycle count data. Over its 10-year existence, Portal has expanded both in the type of data that it receives and in the geographic regions from which it gets data. This paper discusses the …


Engineering Analytics: Research Into The Governance Structure Needed To Integrate The Dominant Design Methodologies, Teddy Steven Cotter Jan 2015

Engineering Analytics: Research Into The Governance Structure Needed To Integrate The Dominant Design Methodologies, Teddy Steven Cotter

Engineering Management & Systems Engineering Faculty Publications

In the ASEM-IAC 2014, Cotter (2014) explored the current state of engineering design, identified the dominate approaches to engineering design, discussed potential contributions from the new field of data analytics to engineering design, and proposed an Engineering Analytics framework that integrates the dominate engineering design approaches and data analytics within a human-intelligence/machine-intelligence (HI-MI) design architecture. This paper reports research applying ontological engineering to integrate the dominate engineering design methodologies into a systemic engineering design decision governance architecture.


Qcm-D Monitoring Of Binding-Induced Conformational Change Of Calmodulin, Hyun J. Kwon, Brian Dodge Jan 2015

Qcm-D Monitoring Of Binding-Induced Conformational Change Of Calmodulin, Hyun J. Kwon, Brian Dodge

Faculty Publications

Understanding conformational changes are important when studying a protein such as calmodulin (CaM), which activates various target enzymes and regulates numerous physiological functions. CaM is a highly flexible protein that can transitorily adopt various conformations. A quartz crystal microbalance with dissipation (QCM-D) sensor was used to study binding-induced conformational changes of surface-immobilized CaM. Structural changes of CaM were evaluated using the Voigt’s viscoelastic model with frequency (ΔF) and dissipation change (ΔD). When Apo-CaM layer was incubated in 0.1 mM Ca2+ solution, the layer decreased by approximately 0.56 nm, due to the release of coupled water molecules and conformational change. The …


Positive Fragments Of Coalgebraic Logics, Adriana Balan, Alexander Kurz, Jirí Velebil Jan 2015

Positive Fragments Of Coalgebraic Logics, Adriana Balan, Alexander Kurz, Jirí Velebil

Engineering Faculty Articles and Research

Positive modal logic was introduced in an influential 1995 paper of Dunn as the positive fragment of standard modal logic. His completeness result consists of an axiomatization that derives all modal formulas that are valid on all Kripke frames and are built only from atomic propositions, conjunction, disjunction, box and diamond. In this paper, we provide a coalgebraic analysis of this theorem, which not only gives a conceptual proof based on duality theory, but also generalizes Dunn's result from Kripke frames to coalgebras for weak-pullback preserving functors. To facilitate this analysis we prove a number of category theoretic results on …


Presenting Distributive Laws, Marcello M. Bonsangue, Helle H. Hansen, Alexander Kurz, Jurriaan Rot Jan 2015

Presenting Distributive Laws, Marcello M. Bonsangue, Helle H. Hansen, Alexander Kurz, Jurriaan Rot

Engineering Faculty Articles and Research

Distributive laws of a monad T over a functor F are categorical tools for specifying algebra-coalgebra interaction. They proved to be important for solving systems of corecursive equations, for the specification of well-behaved structural operational semantics and, more recently, also for enhancements of the bisimulation proof method. If T is a free monad, then such distributive laws correspond to simple natural transformations. However, when T is not free it can be rather difficult to prove the defining axioms of a distributive law. In this paper we describe how to obtain a distributive law for a monad with an equational presentation …


Moore’S Law, Metcalfe’S Law, And The Theory Of Optimal Interoperability, Christopher S. Yoo Jan 2015

Moore’S Law, Metcalfe’S Law, And The Theory Of Optimal Interoperability, Christopher S. Yoo

All Faculty Scholarship

Many observers attribute the Internet’s success to two principles: Moore’s Law and Metcalfe’s Law. These precepts are often cited to support claims that larger networks are inevitably more valuable and that costs in a digital environment always decrease. This Article offers both a systematic description of both laws and then challenges the conventional wisdom by exploring their conceptual limitations. It also explores how alternative mechanisms, such as gateways and competition, can permit the realization benefits typically attributed to Moore’s Law and Metcalfe’s Law without requiring increases in network size.


Needed Computations Shortcutting Needed Steps, Sergio Antoy, Jacob Johannsen, Steven Libby Jan 2015

Needed Computations Shortcutting Needed Steps, Sergio Antoy, Jacob Johannsen, Steven Libby

Computer Science Faculty Publications and Presentations

We define a compilation scheme for a constructor-based, strongly-sequential, graph rewriting system which shortcuts some needed steps. The object code is another constructor-based graph rewriting system. This system is normalizing for the original system when using an innermost strategy. Consequently, the object code can be easily implemented by eager functions in a variety of programming languages. We modify this object code in a way that avoids total or partial construction of the contracta of some needed steps of a computation. When computing normal forms in this way, both memory consumption and execution time are reduced compared to ordinary rewriting computations …


S-Store: Streaming Meets Transaction Processing, John Meehan, Nesime Tatbul, Cansu Aslantas, Ugur Cetintemel, Jiang Du, Tim Kraska, Samuel Madden, David Maier, Andrew Pavlo, Michael Stonebraker, Kristin A. Tufte, Hao Wang Jan 2015

S-Store: Streaming Meets Transaction Processing, John Meehan, Nesime Tatbul, Cansu Aslantas, Ugur Cetintemel, Jiang Du, Tim Kraska, Samuel Madden, David Maier, Andrew Pavlo, Michael Stonebraker, Kristin A. Tufte, Hao Wang

Computer Science Faculty Publications and Presentations

Stream processing addresses the needs of real-time applications. Transaction processing addresses the coordination and safety of short atomic computations. Heretofore, these two modes of operation existed in separate, stove-piped systems. In this work, we attempt to fuse the two computational paradigms in a single system called S-Store. In this way, S-Store can simultaneously accommodate OLTP and streaming applications. We present a simple transaction model for streams that integrates seamlessly with a traditional OLTP system. We chose to build S-Store as an extension of H-Store, an open-source, in-memory, distributed OLTP database system. By implementing S-Store in this way, we can make …


A Theory Of Name Resolution, Pierre Néron, Andrew Tolmach, Eelco Visser, Guido Wachsmuth Jan 2015

A Theory Of Name Resolution, Pierre Néron, Andrew Tolmach, Eelco Visser, Guido Wachsmuth

Computer Science Faculty Publications and Presentations

We describe a language-independent theory for name binding and resolution, suitable for programming languages with complex scoping rules including both lexical scoping and modules. We formulate name resolution as a two-stage problem. First a language-independent scope graph is constructed using language-specific rules from an abstract syntax tree. Then references in the scope graph are resolved to corresponding declarations using a language-independent resolution process. We introduce a resolution calculus as a concise, declarative, and language- independent specification of name resolution. We develop a resolution algorithm that is sound and complete with respect to the calculus. Based on the resolution calculus we …


Usage Based Topology For Dcns, Qing Yi, Suresh Singh Jan 2015

Usage Based Topology For Dcns, Qing Yi, Suresh Singh

Computer Science Faculty Publications and Presentations

Many data center network topologies are designed to provide full bisection bandwidth for tens of thousands of servers in order to achieve high network throughput and server agility. However, the utilization rate of DCNs on average is below 10%, which results in a significant waste of network resources and energy. Many researchers propose consolidating network traffic flows to maximize the set of idle network equipment and switching them to low power mode to save energy. In this paper, we propose using skinnier network topologies to meet performance requirements of realistic loads thus saving not only energy but capital cost as …


Desiderata For A Big Data Language, David Maier Jan 2015

Desiderata For A Big Data Language, David Maier

Computer Science Faculty Publications and Presentations

Data management and analytics systems for big data have proliferated, including column stores, array databases, graphanalysis environments and linear-algebra packages. This burgeoning of systems has lead to a surfeit of language and APIs. It is time to consider a new framework that can span these systems and simplify the programming and maintenance of Big Data applications. There are two key goals for such a framework:

Portability: It should be relatively easy to move an application or tool developed on one platform to operate against another. As a corollary, back-end data and analytics services should be swappable in a particular …


A Demonstration Of The Bigdawg Polystore System, Aaron J. Elmore, Jennie Duggan, Michael Stonebraker, Magdalena Balazinska, Ugur Cetintemel, Vijay Gadepally, J. Heer, Bill Howe, Jeremy Kepner, Tim Kraska, Samuel Madden, David Maier, Timothy G. Mattson, S. Papadopoulos, J. Parkhurst, Nesime Tatbul, Manasi Vartak, Stan Zdonik Jan 2015

A Demonstration Of The Bigdawg Polystore System, Aaron J. Elmore, Jennie Duggan, Michael Stonebraker, Magdalena Balazinska, Ugur Cetintemel, Vijay Gadepally, J. Heer, Bill Howe, Jeremy Kepner, Tim Kraska, Samuel Madden, David Maier, Timothy G. Mattson, S. Papadopoulos, J. Parkhurst, Nesime Tatbul, Manasi Vartak, Stan Zdonik

Computer Science Faculty Publications and Presentations

This paper presents BigDAWG, a reference implementation of a new architecture for “Big Data” applications. Such applications not only call for large-scale analytics, but also for real-time streaming support, smaller analytics at interactive speeds, data visualization, and cross-storage-system queries. Guided by the principle that “one size does not fit all”, we build on top of a variety of storage engines, each designed for a specialized use case. To illustrate the promise of this approach, we demonstrate its effectiveness on a hospital application using data from an intensive care unit (ICU). This complex application serves the needs of doctors and researchers …


Query From Examples: An Iterative, Data-Driven Approach To Query Construction, Hao Li, Chee-Yong Chan, David Maier Jan 2015

Query From Examples: An Iterative, Data-Driven Approach To Query Construction, Hao Li, Chee-Yong Chan, David Maier

Computer Science Faculty Publications and Presentations

In this paper, we propose a new approach, called Query from Examples (QFE), to help non-expert database users construct SQL queries. Our approach, which is designed for users who might be unfamiliar with SQL, only requires that the user is able to determine whether a given output table is the result of his or her intended query on a given input database. To kick-start the construction of a target query Q, the user first provides a pair of inputs: a sample database D and an output table R which is the result of Q on D. As there will be …