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Interoperation For Lazy And Eager Evaluation, William Jeffrey Faught 2011 California Polytechnic State University - San Luis Obispo

Interoperation For Lazy And Eager Evaluation, William Jeffrey Faught

Master's Theses and Project Reports

Programmers forgo existing solutions to problems in other programming lan- guages where software interoperation proves too cumbersome; they remake so- lutions, rather than reuse them. To facilitate reuse, interoperation must resolve language incompatibilities transparently. To address part of this problem, we present a model of computation that resolves incompatible lazy and eager eval- uation strategies using dual notions of evaluation contexts and values to mirror the lazy evaluation strategy in the eager one. This method could be extended to resolve incompatible evaluation strategies for any pair of languages with common expressions.


Coughloc: Location-Aware Indoor Acoustic Sensing For Non-Intrusive Cough Detection, Zheng Sun, Aveek Purohit, Kathleen Yang, Neha Pattan, Dan Siewiorek, Asim Smailagic, Ian Lane, Pei Zhang 2011 Carnegie Mellon University

Coughloc: Location-Aware Indoor Acoustic Sensing For Non-Intrusive Cough Detection, Zheng Sun, Aveek Purohit, Kathleen Yang, Neha Pattan, Dan Siewiorek, Asim Smailagic, Ian Lane, Pei Zhang

Aveek Purohit

Pervasive medical monitoring has become an ideal alter- native to nursing care for elderly people and patients in hospitals. Existing systems using single body-worn sensors are often intrusive and less reliable. By contrast, ubiqui- tous acoustic sensing techniques can support non-intrusive and robust medical monitoring. In this paper, we describe CoughLoc, a ubiquitous acoustic sensing system for con- tinuous cough detection using a wireless sensor network. We show how knowledge of sound source locations can be leveraged to improve the detection accuracy of sound events caused by mobile users. Experiments in indoor environ- ments show our system achieves over 90 ...


Sensorfly: Controlled-Mobile Sensing Platform For Indoor Emergency Response Applications, Aveek Purohit, Zheng Sun, Frank Mokaya, Pei Zhang 2011 Carnegie Mellon University

Sensorfly: Controlled-Mobile Sensing Platform For Indoor Emergency Response Applications, Aveek Purohit, Zheng Sun, Frank Mokaya, Pei Zhang

Aveek Purohit

Indoor emergency response situations, such as urban fire, are characterized by dangerous constantly-changing operating environments with little access to situational information for first responders. In-situ information about the conditions, such as the extent and evolution of an indoor fire, can augment rescue efforts and reduce risk to emergency personnel. Static sensor networks that are pre-deployed or manually deployed have been proposed, but are less practical due to need for large infrastructure, lack of adaptivity and limited coverage. Controlled-mobility in sensor networks, i.e. the capability of nodes to move as per network needs can provide the desired autonomy to overcome ...


Sensorfly: Controlled-Mobile Sensing Platform For Indoor Emergency Response Applications, Aveek Purohit, Zheng Sun, Frank Mokaya, Pei Zhang 2011 Carnegie Mellon University

Sensorfly: Controlled-Mobile Sensing Platform For Indoor Emergency Response Applications, Aveek Purohit, Zheng Sun, Frank Mokaya, Pei Zhang

Zheng Sun

Indoor emergency response situations, such as urban fire, are characterized by dangerous constantly-changing operating environments with little access to situational information for first responders. In-situ information about the conditions, such as the extent and evolution of an indoor fire, can augment rescue efforts and reduce risk to emergency personnel. Static sensor networks that are pre-deployed or manually deployed have been proposed, but are less practical due to need for large infrastructure, lack of adaptivity and limited coverage. Controlled-mobility in sensor networks, i.e. the capability of nodes to move as per network needs can provide the desired autonomy to overcome ...


Unstructured Grid Technologies For Hydrodynamic Applications With Bodies In Relative Motion And Mesh Deformation, Lei Ji 2011 University of Tennessee at Chattanooga

Unstructured Grid Technologies For Hydrodynamic Applications With Bodies In Relative Motion And Mesh Deformation, Lei Ji

Masters Theses and Doctoral Dissertations

Unstructured grid technologies for hydrodynamic applications with bodies in relative motion and mesh deformation are presented. A parallel universal mesh deformation scheme is developed to manage deforming surface and volume grids for both aerodynamic and hydrodynamic applications. The approach is universal and independent of grid type. Also, it requires minimal inter-processor communication and is thus perfectly suitable to a parallel platform. The original scheme of Allen (2006) has difficulty deforming volume grids in regions near concave geometry features and for abrupt grid resolution changes. Several modifications are proposed to overcome these problems. Grid quality can be improved significantly by adding ...


Cortina: Collaborative Context-Aware Indoor Positioning Employing Rss And Rtof Techniques, Zheng Sun, Richard Farley, Telis Kaleas, Judy Ellis, Kiran Chikkappa 2011 Carnegie Mellon University

Cortina: Collaborative Context-Aware Indoor Positioning Employing Rss And Rtof Techniques, Zheng Sun, Richard Farley, Telis Kaleas, Judy Ellis, Kiran Chikkappa

Zheng Sun

Cortina is an energy-efficient indoor localization system, which leverages a wireless sensor network to support navigation and tracking applications. To improve the localization performance, we develop a hybrid ranging system, which incor- porate both RSS and RToF-based techniques. To overcome effects from indoor multipath, we design and implement algorithms to take account various context information. We evaluated the system over a 2000m2 area instrumented with twenty-six fixed nodes. Evaluation results show the system achieved 2.5m accuracy in a pedestrian tracking application.


Adaptive Discrete-Time Controller Design With Neural Network For Hypersonic Flight Vehicle Via Back-Stepping, Bin Xu 2011 Nanyang Technological University, Singapore

Adaptive Discrete-Time Controller Design With Neural Network For Hypersonic Flight Vehicle Via Back-Stepping, Bin Xu

Bin Xu

In this article, the adaptive neural controller in discrete time is investigated for the longitudinal dynamics of a generic hypersonic flight vehicle. The dynamics are decomposed into the altitude subsystem and the velocity subsystem. The altitude subsystem is transformed into the strict-feedback form from which the discrete-time model is derived by the first-order Taylor expansion. The virtual control is designed with nominal feedback and neural network (NN) approximation via back-stepping. Meanwhile, one adaptive NN controller is designed for the velocity subsystem. To avoid the circular construction problem in the practical control, the design of coefficients adopts the upper bound instead ...


Adaptive Neural Control Based On Hgo For Hypersonic Flight Vehicles, Bin Xu 2011 Nanyang Technological University, Singapore

Adaptive Neural Control Based On Hgo For Hypersonic Flight Vehicles, Bin Xu

Bin Xu

This paper describes the design of adaptive neural controller for the longitudinal dynamics of a generic hypersonic flight vehicle (HFV) which are decomposed into two functional systems, namely the altitude subsystem and the velocity subsystem. For each subsystem, one adaptive neural controller is investigated based on the normal output-feedback formulation. For the altitude subsystem, the high gain observer (HGO) is taken to estimate the unknown newly defined states. Only one neural network (NN) is employed to approximate the lumped uncertain system nonlinearity during the controller design which is considerably simpler than the ones based on back-stepping scheme with the strict-feedback ...


Task Allocation For Multi-Spacecraft Cooperation Based On Estimation Of Distribution Algorithm, Bin Xu 2011 Nanyang Technological University, Singapore

Task Allocation For Multi-Spacecraft Cooperation Based On Estimation Of Distribution Algorithm, Bin Xu

Bin Xu

One two-stage task allocation strategy is proposed for multi-spacecraft cooperation during the long-range orbit transfer with two impulses. This paper focuses on the task value maximum and cost minimum optimization by assigning spacecraft to different task. At the first stage time and energy cost are considered based on the spacecraft dynamics. The optimization result is together with the target value as the factor for the task allocation model at the second stage. The optimization is processed separately in continuous and discrete time domain with estimation of distribution algorithm (EDA). Different task allocation mode is formulated and the strategy is verified ...


Composite Control Based On Optimal Torque Control And Adaptive Kriging Control For The Crab Rover, Bin Xu 2011 Nanyang Technological University, Singapore

Composite Control Based On Optimal Torque Control And Adaptive Kriging Control For The Crab Rover, Bin Xu

Bin Xu

Terrainability is mostly dependant on the suspension mechanism and the control of a space rover. For the six wheeled CRAB rover, this paper presents the composite control design with torque control and adaptive Kriging control to improve the terrainability, somewhat related to minimizing heel slip. As CRAB is moving slowly, the torque control is processed by minimizing the variance of the required friction coefficient based on the static model. Adaptive Kriging control is used to track the commanded velocity. The system uncertainty is compensated by Kriging estimation based on the velocity dynamics. Experiment results with two different tires show the ...


Adaptive Hypersonic Flight Control Via Back-Stepping And Kriging Estimation, Bin Xu 2011 Nanyang Technological University, Singapore

Adaptive Hypersonic Flight Control Via Back-Stepping And Kriging Estimation, Bin Xu

Bin Xu

This paper investigates the adaptive Kriging controller for the longitudinal dynamics of a generic hypersonic flight vehicle (HFV). For the altitude subsystem, the dynamics are transformed into the strict-feedback form where the backstepping scheme is employed. Considering the nonlinearity of the dynamics, the nominal feedback is included in the controller while Kriging system is designed to estimate the uncertainty. With the proposed controller, the almost surely bounded stability is guaranteed. The simulation study is presented to show the effectiveness of the proposed control approach.


Termodynamika Procesowa (Dla Me Aparatura Procesowa) Ćw., Wojciech M. Budzianowski 2011 Wroclaw University of Technology

Termodynamika Procesowa (Dla Me Aparatura Procesowa) Ćw., Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


The Analysis Of Heat Transfer In A Gas-Gas Heat Exchanger Operated Under A Heat-Recirculating Mode, Mariusz Salaniec, Wojciech M. Budzianowski 2011 Wroclaw University of Technology

The Analysis Of Heat Transfer In A Gas-Gas Heat Exchanger Operated Under A Heat-Recirculating Mode, Mariusz Salaniec, Wojciech M. Budzianowski

Wojciech Budzianowski

The present paper presents the analysis of heat transfer in a gas-gas heat exchanger operated in a heat-recirculating mode.


An Overview Of Technologies For Upgrading Of Biogas To Biomethane, Wojciech M. Budzianowski 2011 Wroclaw University of Technology

An Overview Of Technologies For Upgrading Of Biogas To Biomethane, Wojciech M. Budzianowski

Wojciech Budzianowski

The present contribution presents an overview of technologies available for upgrading of biogas to biomethane. Technologies under study include pressure swing adsorption (PSA), high-pressure water wash (HPWW), reactive absorption (RA), physical absorption (PA), membrane separation (MS) and cryogenic separation (CS).


Influence Of Energy Policy On The Rate Of Implementation Of Biogas Power Plants In Germany During The 2001-2010 Decade, Izabela Chasiak, Wojciech M. Budzianowski 2011 Wroclaw University of Technology

Influence Of Energy Policy On The Rate Of Implementation Of Biogas Power Plants In Germany During The 2001-2010 Decade, Izabela Chasiak, Wojciech M. Budzianowski

Wojciech Budzianowski

The current article describes energy policy tools, which caused intensive development of biogas-based power generation in Germany during the 2001-2010 decade. The German system of financial support to biogas power plants is presented in details. It is shown that in Germany, i.e. in a country characterised by similar climate and potentials to renewable energy to Poland, biogas power plants cover 10,7% of electricity demands in 2010, while all renewable energy sources cover only 5,4% of electricity demands. It is emphasised that under favourable Polish energy policy, the development of biogas energy can be very rapid.


Infoextractor – A Tool For Social Media Data Mining, Chirag Shah, Charles File 2011 Rutgers University - New Brunswick/Piscataway

Infoextractor – A Tool For Social Media Data Mining, Chirag Shah, Charles File

JITP 2011: The Future of Computational Social Science

We present InfoExtractor, a web-based tool for collecting data and metadata from focused social media content. InfoExtractor then provides this data in various structured and unstructured formats for easy manipulation and analysis. The tool allows social science researchers to easily collect data for quantitative analysis, and is designed to deliver data from popular and influential social media sites in a useful and easy to access way. InfoExtractor was designed to replace traditional means of content aggregation, such as page scraping and brute- force copying.


Tradeoffs In Accuracy And Efficiency In Supervised Learning Methods, Loren Collingwood, John Wilkerson 2011 University of Washington

Tradeoffs In Accuracy And Efficiency In Supervised Learning Methods, Loren Collingwood, John Wilkerson

JITP 2011: The Future of Computational Social Science

Text is becoming a central source of data for social science research. With advances in digitization and open records practices, the central challenge has in large part shifted away from availability to usability. Automated text classification methodologies are becoming increasingly important within political science because they hold the promise of substantially reducing the costs of converting text to data for a variety of tasks. In this paper, we consider a number of questions of interest to prospective users of supervised learning methods, which are appropriate to classification tasks where known categories are applied. For the right task, supervised learning methods ...


Researching Real-World Web Use With Roxy, A Research Proxy, Ericka Menchen-Trevino, Chris Karr 2011 Northwestern University

Researching Real-World Web Use With Roxy, A Research Proxy, Ericka Menchen-Trevino, Chris Karr

JITP 2011: The Future of Computational Social Science

Outside of a lab environment, it has been difficult for researchers to collect both behavioral and self-reported Web-use data from the same participants. To address this challenge we created Roxy, open source software that collects real-world Web-use data with participants’ informed consent. Roxy gathers Web log data as well as the text and HTML code of each page visited by participants. We describe Roxy’s data gathering capabilities and search functions and then illustrate how we used the software in a multi-method study. The use case examines selective exposure to political communication during the November 2010 U.S. general election ...


An Automated Snowball Census Of The Political Web, Abe Gong 2011 University of Michigan

An Automated Snowball Census Of The Political Web, Abe Gong

JITP 2011: The Future of Computational Social Science

This paper solves a persistent methodological problem for social scientists studying the political web: representative sampling. Virtu- ally all existing studies of the political web are based on incomplete samples, and therefore lack generalizability. In this paper, I combine methods from computer science and sampling theory to conduct an automated snowball census of the political web and constructs an all- but-complete index of English political websites. I check the robust- ness of this index, use it to generate descriptive statistics for the entire political web, and demonstrate that studies based on ad hoc sampling strategies are likely to be biased ...


Facilitating Encounters With Political Difference: Engaging Voters With The Living Voters Guide, Deen G. Freelon, Travis Kriplean, John Morgan, W. Lance Bennett, Alan Borning 2011 University of Washington

Facilitating Encounters With Political Difference: Engaging Voters With The Living Voters Guide, Deen G. Freelon, Travis Kriplean, John Morgan, W. Lance Bennett, Alan Borning

JITP 2011: The Future of Computational Social Science

Unlike 20th-century mass media, the Internet requires self-selection of content by its very nature. This has raised the normative concern that users may opt to encounter only political information and perspectives that accord with their preexisting views. This study examines the different ways that voters appropriated a new, purpose-built online engagement platform to engage with a wide variety of political opinions and arguments. In a deployment aimed at helping Washington state citizens make their 2010 election decisions, we find that users take significant advantage of three key opportunities to engage with political diversity: reading, acknowledging, and writing arguments on both ...


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