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Selected Works

2015

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Full-Text Articles in Computer Engineering

Dynamic Modeling, Parameter Estimation And Control Of A Leg Prosthesis Test Robot, Hanz Richter, Daniel Simon, William Smith, Sergey Samorezov Dec 2015

Dynamic Modeling, Parameter Estimation And Control Of A Leg Prosthesis Test Robot, Hanz Richter, Daniel Simon, William Smith, Sergey Samorezov

Hanz Richter

Robotic testing can facilitate the development of new concepts, designs and control systems for prosthetic limbs. Human subject test clearances, safety and the lack of repeatability associated with human trials can be reduced or eliminated with automated testing, and test modalities are possible which are dangerous or inconvenient to attempt with patients. This paper describes the development, modeling, parameter estimation and control of a robot capable of reproducing two degree-of-freedom hip motion in the sagittal plane. Hip vertical displacement and thigh angle motion profiles are applied to a transfemoral prosthesis attached to the robot. A treadmill is used as walking …


Data And Network Optimization Effect On Web Performance, Steven Rosenberg, Surbhi Dangi, Isuru Warnakulasooriya Dec 2015

Data And Network Optimization Effect On Web Performance, Steven Rosenberg, Surbhi Dangi, Isuru Warnakulasooriya

Surbhi Dangi

In this study, we measure the effects of two software approaches to improving data and network performance: 1. Content optimization and compression; and 2. Optimizing network protocols. We achieve content optimization and compression by means of BoostEdge by ActivNetworks and employ the SPDY network protocol by Google to lower the round trip time for HTTP transactions. Since the data and transport layers are separate, we conclude our investigation by studying the combined effect of these two techniques on web performance. Using document mean load time as the measure, we found that with and without packet loss, both BoostEdge and SPDY …


Vanadium Oxide Thin-Film Variable Resistor-Based Rf Switches, Kuanchang Pan, Weisong Wang, Eunsung Shin, Kelvin Freeman, Guru Subramanyam Dec 2015

Vanadium Oxide Thin-Film Variable Resistor-Based Rf Switches, Kuanchang Pan, Weisong Wang, Eunsung Shin, Kelvin Freeman, Guru Subramanyam

Guru Subramanyam

Vanadium dioxide (VO2) is a unique phase change material (PCM) that possesses a metal-to-insulator transition property. Pristine VO2 has a negative temperature coefficient of resistance, and it undergoes an insulator-to-metal phase change at a transition temperature of 68°C. Such a property makes the VO2 thin-film-based variable resistor (varistor) a good candidate in reconfigurable electronics to be integrated with different RF devices such as inductors, varactors, and antennas. Series single-pole single-throw (SPST) switches with integrated VO2 thin films were designed, fabricated, and tested. The overall size of the device is 380 μm × 600 μm. The SPST switches were fabricated on …


A High Performance Ceramic-Polymer Separator For Lithium Batteries, Jitendra Kumar, Padmakar Kichambare, Amarendra K. Rai, Rabi Bhattacharya, Stanley J. Rodrigues, Guru Subramanyam Dec 2015

A High Performance Ceramic-Polymer Separator For Lithium Batteries, Jitendra Kumar, Padmakar Kichambare, Amarendra K. Rai, Rabi Bhattacharya, Stanley J. Rodrigues, Guru Subramanyam

Guru Subramanyam

A three-layered (ceramic-polymer-ceramic) hybrid separator was prepared by coating ceramic electrolyte [lithium aluminum germanium phosphate (LAGP)] over both sides of polyethylene (PE) polymer membrane using electron beam physical vapor deposition (EB-PVD) technique. Ionic conductivities of membranes were evaluated after soaking PE and LAGP/PE/LAGP membranes in a 1 Molar (1M) lithium hexafluroarsenate (LiAsF6) electrolyte in ethylene carbonate (EC), dimethyl carbonate (DMC) and ethylmethyl carbonate (EMC) in volume ratio (1:1:1). Scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques were employed to evaluate morphology and structure of the separators before and after cycling performance tests to better understand structure-property correlation. As compared …


Industry-University Collaboration: A University Of Dayton Model, Guru Subramanyam Dec 2015

Industry-University Collaboration: A University Of Dayton Model, Guru Subramanyam

Guru Subramanyam

This paper introduces industry-university collaboration activities currently in place at the University of Dayton's School of Engineering. These collaborations are important to prepare industry-ready graduates who excel in technical, entrepreneurial, and leadership skills. One of the key curricular components is the industry-sponsored multidisciplinary projects. Industry involvement in advisory committee, strategic research partnerships, and other forms are discussed.


Can Declared Strategy Voting Be An Effective Instrument For Group Decision-Making?, Lorrie Cranor Dec 2015

Can Declared Strategy Voting Be An Effective Instrument For Group Decision-Making?, Lorrie Cranor

Lorrie F Cranor

The goal of this research is to determine whether declared strategy voting can be an effective tool for group decision-making. Declared strategy voting is a novel group decision-making procedure in which preference is specified using voting strategies - first-order mathematical functions that specify a choice in terms of zero or more parameters. This research will focus on refining the declared strategy voting concept, developing an accessible implementation of declared strategy voting that can be used for mock elections, assessing the potential impacts of declared strategy voting, and evaluating the effectiveness of declared strategy voting for group decision-making. This proposal describes …


Design And Implementation Of A Practical Security-Conscious Electronic Polling System, Lorrie Cranor, Ron Cytron Dec 2015

Design And Implementation Of A Practical Security-Conscious Electronic Polling System, Lorrie Cranor, Ron Cytron

Lorrie F Cranor

We present the design and implementation of Sensus, a practical, secure and private system for conducting surveys and elections over computer networks. Expanding on the work of Fujioka, Okamoto, and Ohta, Sensus uses blind signatures to ensure that only registered voters can vote and that each registered voter only votes once, while at the same time maintaining voters' privacy. Sensus allows voters to verify independently that their votes were counted correctly, and anonymously challenge the results should their votes be miscounted. We outline seven desirable properties of voting systems and show that Sensus satisfied these properties well, in some cases …


Adaptive Beam Director For A Tiled Fiber Array, Mikhail Vorontsov, Jim F. Riker, Ernst Polnau, Svetlana Lachinova, Venkata S. Rao Gudimetla Nov 2015

Adaptive Beam Director For A Tiled Fiber Array, Mikhail Vorontsov, Jim F. Riker, Ernst Polnau, Svetlana Lachinova, Venkata S. Rao Gudimetla

Mikhail Vorontsov

We present the concept development of a novel atmospheric compensation system based on adaptive tiled fiber array architecture operating with target-in-the-loop scenarios for directed beam applications. The adaptive tiled fiber array system is integrated with adaptive beam director (ABD). Wavefront control and sensing functions are performed directly on the beam director telescope primary mirror. The beam control of the adaptive tiled fiber array aims to compensate atmospheric turbulence-induced dynamic phase aberrations and results in a corresponding brightness increase on the illuminated extended object. The system is specifically designed for tiled fiber system architectures operating in strong intensity scintillation and speckle-modulation …


Characterization Of Atmospheric Turbulence Effects Over 149 Km Propagation Path Using Multi-Wavelength Laser Beacons, Mikhail Vorontsov, Gary W. Carhart, Venkata S. Rao Gudimetla, Thomas Weyrauch, Eric Stevenson, Svetlana Lachinova, Leonid A. Beresnev, Jony Jiang Liu, Karl Rehder, Jim F. Riker Nov 2015

Characterization Of Atmospheric Turbulence Effects Over 149 Km Propagation Path Using Multi-Wavelength Laser Beacons, Mikhail Vorontsov, Gary W. Carhart, Venkata S. Rao Gudimetla, Thomas Weyrauch, Eric Stevenson, Svetlana Lachinova, Leonid A. Beresnev, Jony Jiang Liu, Karl Rehder, Jim F. Riker

Mikhail Vorontsov

We describe preliminary results of a set of laser beam propagation experiments performed over a long (149 km) near-horizontal propagation path between Mauna Loa (Hawaii Island) and Haleakala (Island of Maui) mountains in February 2010. The distinctive feature of the experimental campaign referred to here as the Coherent Multi-Beam Atmospheric Transceiver (COMBAT) experiments is that the measurements of the atmospheric-turbulence induced laser beam intensity scintillations at the receiver telescope aperture were obtained simultaneously using three laser sources (laser beacons) with different wavelengths (λ1 = 0.53 μm, λ2 = 1.06 μm, and λ3 = 1.55 μm). The presented experimental results on …


Comparison Of Turbulence-Induced Scintillations For Multi-Wavelength Laser Beacons Over Tactical (7 Km) And Long (149 Km) Atmospheric Propagation Paths, Mikhail Vorontsov, Venkata S. Rao Gudimetla, Gary W. Carhart, Thomas Weyrauch, Svetlana Lachinova, Ernst Polnau, Joseph Rierson, Leonid A. Beresnev, Jony Jiang Liu, Jim F. Riker Nov 2015

Comparison Of Turbulence-Induced Scintillations For Multi-Wavelength Laser Beacons Over Tactical (7 Km) And Long (149 Km) Atmospheric Propagation Paths, Mikhail Vorontsov, Venkata S. Rao Gudimetla, Gary W. Carhart, Thomas Weyrauch, Svetlana Lachinova, Ernst Polnau, Joseph Rierson, Leonid A. Beresnev, Jony Jiang Liu, Jim F. Riker

Mikhail Vorontsov

We report results of the experimental analysis of atmospheric effects on laser beam propagation over two distinctive propagation paths: a long-range (149 km) propagation path between Mauna Loa (Island of Hawaii) and Haleakala (Island of Maui) mountains, and a tactical-range (7 km) propagation path between the roof of the Dayton Veterans Administration Medical Center (VAMC) and the Intelligent Optics Laboratory (IOL/UD) located on the 5th floor of the University of Dayton College Park Center building. Both testbeds include three laser beacons operating at wavelengths 532 nm, 1064 nm, and 1550 nm and a set of identical optical receiver systems with …


Atmospheric Turbulence Compensation Of Point Source Images Using Asynchronous Stochastic Parallel Gradient Descent Technique On Amos 3.6 M Telescope, Mikhail Vorontsov, Jim F. Riker, Gary W. Carhart, Venkata S. Rao Gudimetla, Leonid A. Beresnev, Thomas Weyrauch Nov 2015

Atmospheric Turbulence Compensation Of Point Source Images Using Asynchronous Stochastic Parallel Gradient Descent Technique On Amos 3.6 M Telescope, Mikhail Vorontsov, Jim F. Riker, Gary W. Carhart, Venkata S. Rao Gudimetla, Leonid A. Beresnev, Thomas Weyrauch

Mikhail Vorontsov

The Stochastic Parallel Gradient Descent Technique-based Adaptive Optics (SPGD-AO) system described in this presentation does not use a conventional wavefront sensor. It uses a metric signal collected by a single pixel detector placed behind a pinhole in the image plane to drive three deformable mirrors (DMs). The system is designed to compensate the image for turbulence effects. The theory behind this method is described in detail in [1]. However this technique, while widely simulated and tested in the laboratory, was not yet verified in astronomical field site experiments. During the month of May 2007, a series of experiments with SPGD-AO …


Pocket Deformable Mirror For Adaptive Optics Applications, Leonid A. Beresnev, Mikhail Vorontsov, Peter Wangsness Nov 2015

Pocket Deformable Mirror For Adaptive Optics Applications, Leonid A. Beresnev, Mikhail Vorontsov, Peter Wangsness

Mikhail Vorontsov

Adaptive/active optical elements are designed to improve optical system performance in the presence of phase aberrations. For atmospheric optics and astronomical applications, an ideal deformable mirror should have sufficient frequency bandwidth for compensation of fast changing wave front aberrations induced by either atmospheric turbulences or by turbulent air flows surrounding a flying object (air optical effects). In many applications, such as atmospheric target tracking, remote sensing from flying aircraft, boundary layer imaging, laser communication and laser beam projection over near horizontal propagation paths the phase aberration frequency bandwidth can exceed several kHz. These fast-changing aberrations are currently compensated using relatively …


Adaptive Optics Performance Over Long Horizontal Paths: Aperture Effects In Multi-Conjugate Adaptive Optical Systems, Miao Yu, Mikhail Vorontsov, Svetlana Lachinova, Jim F. Riker, Venkata S. Rao Gudimetla Nov 2015

Adaptive Optics Performance Over Long Horizontal Paths: Aperture Effects In Multi-Conjugate Adaptive Optical Systems, Miao Yu, Mikhail Vorontsov, Svetlana Lachinova, Jim F. Riker, Venkata S. Rao Gudimetla

Mikhail Vorontsov

We analyze various scenarios of the aperture effects in adaptive optical receiver-type systems when inhomogeneities of the wave propagation medium are distributed over long horizontal propagation path, or localized in a few thin layers remotely located from the receiver telescope pupil. Phase aberration compensation is performed using closed-loop control architectures based on phase conjugation and decoupled stochastic parallel gradient descent (DSPGD) control algorithms. Both receiver system aperture diffraction effects and the impact of wave-front corrector position on phase aberration compensation efficiency are analyzed for adaptive systems with single or multiple wave-front correctors.


Bridging Researchers’ Active Data Storage Needs, Matt Schultz Oct 2015

Bridging Researchers’ Active Data Storage Needs, Matt Schultz

Matt Schultz

The 2015 Midwest Data Librarian Symposium was the inaugural launch of this now widely-attended un-conference series. Attendees were encouraged to submit lightning presentations on local developments in the area of data management support from within their Libraries. This brief presentation highlighted early work undertaken to develop a checklist that my role as Metadata & Digital Curation could make use of to navigate faculty researcher questions that arise when considering where to store and maintain research data during active stages of any given sponsored research project.


Gvsu Repository Migration Update, Matt Schultz Oct 2015

Gvsu Repository Migration Update, Matt Schultz

Matt Schultz

In late 2015, GVSU Libraries carried out a full-scale usability evaluation on their new digital preservation and access solution known as Preservica. The evaluation was geared primarily towards the access interface in order to ensure that GVSU faculty and students would have success in navigating the digital collections. In this presentation for the Mid-Michigan Digital Practitioners (MMDP) community, preliminary findings from the evaluations are shared.


Integrate Webex Recorded Meetings With Video Sharing Development, Zhi-Xue Xu Sep 2015

Integrate Webex Recorded Meetings With Video Sharing Development, Zhi-Xue Xu

Zhi-Xue Xu

WebEx has provided powerful online meeting and video conference. Many important meetings have been held by WebEx. We should record these important meetings in time on WebEx. WebEx meetings can be recorded to the streaming video files that will be stored in the WebEx Server and back play them repeatedly if you want. The WebEx recorded meeting files with ARF format can be converted to WMV, SWF and MP4 format video files by WebEx Network Recording Player. The more different video formats, AVI, FLV, MOV, and MPEG4 also can be converted by third parties video convert software. The format WMV …


Answer Credibility: A Language Modeling Approach To Answer Validation, Protima Banerjee, Hyoil Han Sep 2015

Answer Credibility: A Language Modeling Approach To Answer Validation, Protima Banerjee, Hyoil Han

Hyoil Han

Answer Validation is a topic of significant interest within the Question Answering community. In this paper, we propose the use of language modeling methodologies for Answer Validation, using corpus-based methods that do not require the use of external sources. Specifically, we propose a model for Answer Credibility which quantifies the reliability of a source document that contains a candidate answer and the Question’s Context Model.


Survey Of Word Sense Disambiguation Approaches, Xiaohua Zhou, Hyoil Han Sep 2015

Survey Of Word Sense Disambiguation Approaches, Xiaohua Zhou, Hyoil Han

Hyoil Han

Word Sense Disambiguation (WSD) is an important but challenging technique in the area of natural language processing (NLP). Hundreds of WSD algorithms and systems are available, but less work has been done in regard to choosing the optimal WSD algorithms. This paper summarizes the various knowledge sources used for WSD and classifies existing WSD algorithms according to their techniques. The rationale, tasks, performance, knowledge sources used, computational complexity, assumptions, and suitable applications for each class of WSD algorithms are also discussed. This paper will provide users with general knowledge for choosing WSD algorithms for their specific applications or for further …


Software Metrics And Dashboard, Shilpika Shilpika, George K. Thiruvathukal, Saulo Aguiar, Konstantin Läufer, Nicholas J. Hayward Aug 2015

Software Metrics And Dashboard, Shilpika Shilpika, George K. Thiruvathukal, Saulo Aguiar, Konstantin Läufer, Nicholas J. Hayward

George K. Thiruvathukal

Software metrics are a critical tool which provide continuous insight to products and processes and help build reliable software in mission critical environments. Using software metrics we can perform calculations that help assess the effectiveness of the underlying software or process. The two types of metrics relevant to our work is complexity metrics and in-process metrics. Complexity metrics tend to focus on intrinsic code properties like code complexity. In-process metrics focus on a higher-level view of software quality, measuring information that can provide insight into the underlying software development process.

Our aim is to develop and evaluate a metrics dashboard …


The Gasday Project At Marquette University: A Learning Laboratory In A Functioning Business, Ronald H. Brown, Thomas F. Quinn, George Corliss, Jay R. Goldberg, Mark L. Nagurka Aug 2015

The Gasday Project At Marquette University: A Learning Laboratory In A Functioning Business, Ronald H. Brown, Thomas F. Quinn, George Corliss, Jay R. Goldberg, Mark L. Nagurka

Ronald Brown

No abstract provided.


Forecasting Natural Gas Demand: The Role Of Physical And Economic Factors, Ronald H. Brown, David E. Clark, George Corliss, Farrokh Nourzad, Thomas F. Quinn, Catherine Twetten Aug 2015

Forecasting Natural Gas Demand: The Role Of Physical And Economic Factors, Ronald H. Brown, David E. Clark, George Corliss, Farrokh Nourzad, Thomas F. Quinn, Catherine Twetten

Ronald Brown

No abstract provided.


Dense And Switched Modular Primitives For Bond Graph Model Design, K. Seo, Z. Fan, Jianjun Hu, E. Goodman, R. Rosenberg Jun 2015

Dense And Switched Modular Primitives For Bond Graph Model Design, K. Seo, Z. Fan, Jianjun Hu, E. Goodman, R. Rosenberg

Jianjun Hu

No abstract provided.


Automated Synthesis Of Mechanical Vibration Absorbers Using Genetic Programming, Jianjun Hu, E. Goodman, S. Li, R. Rosenberg Jun 2015

Automated Synthesis Of Mechanical Vibration Absorbers Using Genetic Programming, Jianjun Hu, E. Goodman, S. Li, R. Rosenberg

Jianjun Hu

No abstract provided.


System-Level Synthesis Of Mems Via Genetic Programming And Bond Graphs, Z. Fan, K. Seo, Jianjun Hu, R. Rosenberg, E. Goodman Jun 2015

System-Level Synthesis Of Mems Via Genetic Programming And Bond Graphs, Z. Fan, K. Seo, Jianjun Hu, R. Rosenberg, E. Goodman

Jianjun Hu

No abstract provided.


Towards Real-Time, On-Board, Hardware-Supported Sensor And Software Health Management For Unmanned Aerial Systems, Johann M. Schumann, Kristin Y. Rozier, Thomas Reinbacher, Ole J. Mengshoel, Timmy Mbaya, Corey Ippolito Jun 2015

Towards Real-Time, On-Board, Hardware-Supported Sensor And Software Health Management For Unmanned Aerial Systems, Johann M. Schumann, Kristin Y. Rozier, Thomas Reinbacher, Ole J. Mengshoel, Timmy Mbaya, Corey Ippolito

Ole J Mengshoel

For unmanned aerial systems (UAS) to be successfully deployed and integrated within the national airspace, it is imperative that they possess the capability to effectively complete their missions without compromising the safety of other aircraft, as well as persons and property on the ground. This necessity creates a natural requirement for UAS that can respond to uncertain environmental conditions and emergent failures in real-time, with robustness and resilience close enough to those of manned systems. We introduce a system that meets this requirement with the design of a real-time onboard system health management (SHM) capability to continuously monitor sensors, software, …


Towards Synthesis Of Platform-Aware Attack-Resilient Control Systems: Extended Abstract, Miroslav Pajic, Nicola Bezzo, James Weimer, Rajeev Alur, Rahul Mangharam, Nathan Michael, George Pappas, Oleg Sokolsky, Paulo Tabuada, Stephanie Weirich, Insup Lee Jun 2015

Towards Synthesis Of Platform-Aware Attack-Resilient Control Systems: Extended Abstract, Miroslav Pajic, Nicola Bezzo, James Weimer, Rajeev Alur, Rahul Mangharam, Nathan Michael, George Pappas, Oleg Sokolsky, Paulo Tabuada, Stephanie Weirich, Insup Lee

Stephanie Weirich

No abstract provided.


Contracts Made Manifest, Michael Greenberg, Benjamin C. Pierce, Stephanie Weirich Jun 2015

Contracts Made Manifest, Michael Greenberg, Benjamin C. Pierce, Stephanie Weirich

Stephanie Weirich

Since Findler and Felleisen (Findler, R. B. & Felleisen, M. 2002) introduced higher-order contracts, many variants have been proposed. Broadly, these fall into two groups: some follow Findler and Felleisen (2002) in using latent contracts, purely dynamic checks that are transparent to the type system; others use manifest contracts, where refinement types record the most recent check that has been applied to each value. These two approaches are commonly assumed to be equivalent—different ways of implementing the same idea, one retaining a simple type system, and the other providing more static information. Our goal is to formalize and clarify this …


Combining Proofs And Programs In A Dependently Typed Language, Stephanie Weirich, Vilhelm Sjoberg, Chris Casinghino Jun 2015

Combining Proofs And Programs In A Dependently Typed Language, Stephanie Weirich, Vilhelm Sjoberg, Chris Casinghino

Stephanie Weirich

Most dependently-typed programming languages either require that all expressions terminate (e.g. Coq, Agda, and Epigram), or allow infinite loops but are inconsistent when viewed as logics (e.g. Haskell, ATS, mega). Here, we combine these two approaches into a single dependently-typed core language. The language is composed of two fragments that share a common syntax and overlapping semantics: a logic that guarantees total correctness, and a call-by-value programming language that guarantees type safety but not termination. The two fragments may interact: logical expressions may be used as programs; the logic may soundly reason about potentially nonterminating programs; programs can require logical …


Programming Up To Congruence (Extended Version), Vilhelm Sjoberg, Stephanie Weirich Jun 2015

Programming Up To Congruence (Extended Version), Vilhelm Sjoberg, Stephanie Weirich

Stephanie Weirich

This paper presents the design of ZOMBIE, a dependently-typed programming language that uses an adaptation of a congruence closure algorithm for proof and type inference. This algorithm allows the type checker to automatically use equality assumptions from the context when reasoning about equality. Most dependently typed languages automatically use equalities that follow from -reduction during type checking; however, such reasoning is incompatible with congruence closure. In contrast, ZOMBIE does not use automatic -reduction because types may contain potentially diverging terms. Therefore ZOMBIE provides a unique opportunity to explore an alternative definition of equivalence in dependently typed language design. Our work …


Closed Type Families With Overlapping Equations (Extended Version), Richard A. Eisenberg, Dimitrios Vytiniotis, Simon Peyton Jones, Stephanie Weirich Jun 2015

Closed Type Families With Overlapping Equations (Extended Version), Richard A. Eisenberg, Dimitrios Vytiniotis, Simon Peyton Jones, Stephanie Weirich

Stephanie Weirich

Open, type-level functions are a recent innovation in Haskell that move Haskell towards the expressiveness of dependent types, while retaining the look and feel of a practical programming language. This paper shows how to increase expressiveness still further, by adding closed type functions whose equations may overlap, and may have non-linear patterns over an open type universe. Although practically useful and simple to implement, these features go beyond conventional dependent type theory in some respects, and have a subtle metatheory.