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2015

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Articles 6361 - 6390 of 7524

Full-Text Articles in Engineering

Mr4rf: Mem-Device With Impedance And Their Usage With Impedance Matching Networks For Passive Rfid Tags In The Uhf, George H. Harris Jan 2015

Mr4rf: Mem-Device With Impedance And Their Usage With Impedance Matching Networks For Passive Rfid Tags In The Uhf, George H. Harris

Masters Theses

"The passive RFID tag in the UHF has been employed in several different applications including, tracking, logistics, and as a sensing platform for the Internet of things (IoT). The tag is ideal for this industry due to its unique design. It harvests all of its energy from the environment, and is small, cheap, and requires little to no maintenance. However, there are two major issues limiting the potential of the passive RFID systems: the limited power harvested by the tag, and the high susceptibility to interference and coupling. In particular, dynamic environments render the traditionally fixed, RF impedance matching network …


Discrete-Time Neural Network Based State Observer With Neural Network Based Control Formulation For A Class Of Systems With Unmatched Uncertainties, Jason Michael Stumfoll Jan 2015

Discrete-Time Neural Network Based State Observer With Neural Network Based Control Formulation For A Class Of Systems With Unmatched Uncertainties, Jason Michael Stumfoll

Masters Theses

"An observer is a dynamic system that estimates the state variables of another system using noisy measurements, either to estimate unmeasurable states, or to improve the accuracy of the state measurements. The Modified State Observer (MSO) is a technique that uses a standard observer structure modified to include a neural network to estimate system states as well as system uncertainty. It has been used in orbit uncertainty estimation and atmospheric reentry uncertainty estimation problems to correctly estimate unmodeled system dynamics. A form of the MSO has been used to control a nonlinear electrohydraulic system with parameter uncertainty using a simplified …


Deforming Diamond, Ciprian Borcea, Ileana Streinu Jan 2015

Deforming Diamond, Ciprian Borcea, Ileana Streinu

Computer Science: Faculty Publications

For materials science, diamond crystals are almost unrivaled for hardness and a range of other properties. Yet, when simply abstracting the carbon bonding structure as a geometric bar-and-joint periodic framework, it is far from rigid. We study the geometric deformations of this type of framework in arbitrary dimension d, with particular regard to the volume variation of a unit cell.


Sustainable Design Of Buildings Using Semantic Bim And Semantic Web Services, Mehrdad Niknam, Saeed Karshenas Jan 2015

Sustainable Design Of Buildings Using Semantic Bim And Semantic Web Services, Mehrdad Niknam, Saeed Karshenas

Civil and Environmental Engineering Faculty Research and Publications

In response to the growing concerns about climate change and the environment, sustainable design of buildings is increasingly demanded by building owners and users. However, fast evaluation of various design options and identification of the optimized design requires application of design analysis tools such as energy modeling, daylight simulations, and natural ventilation analysis software. Energy analysis requires access to distributed sources of information such as building element material properties provided by designers, mechanical equipment information provided by equipment manufacturers, weather data provided by weather reporting agencies, and energy cost data from energy providers. Gathering energy related information from different sources …


The Impact Of Capsid Proteins On Virus Removal And Inactivation During Water Treatment Processes, Brooke K. Mayer, Yu Yang, Daniel Gerrity, Morteza A. Abbaszadegan Jan 2015

The Impact Of Capsid Proteins On Virus Removal And Inactivation During Water Treatment Processes, Brooke K. Mayer, Yu Yang, Daniel Gerrity, Morteza A. Abbaszadegan

Civil and Environmental Engineering Faculty Research and Publications

This study examined the effect of the amino acid composition of protein capsids on virus inactivation using ultraviolet (UV) irradiation and titanium dioxide photocatalysis, and physical removal via enhanced coagulation using ferric chloride. Although genomic damage is likely more extensive than protein damage for viruses treated using UV, proteins are still substantially degraded. All amino acids demonstrated significant correlations with UV susceptibility. The hydroxyl radicals produced during photocatalysis are considered nonspecific, but they likely cause greater overall damage to virus capsid proteins relative to the genome. Oxidizing chemicals, including hydroxyl radicals, preferentially degrade amino acids over nucleotides, and the amino …


The Role Of Shrinkage Strains Causing Early-Age Cracking In Cast-In-Place Concrete Bridge Decks, Tayyebeh Mohammadi, Baolin Wan, Christopher M. Foley Jan 2015

The Role Of Shrinkage Strains Causing Early-Age Cracking In Cast-In-Place Concrete Bridge Decks, Tayyebeh Mohammadi, Baolin Wan, Christopher M. Foley

Civil and Environmental Engineering Faculty Research and Publications

Early-age cracking in cast-in-place reinforced concrete bridge decks is occurring more frequently now than three decades ago and principle factors that lead to early-age deck cracking are not fully understood. A finite element (FE) simulation methodology for assessing the role of shrinkage-induced strains in generating early-age bridge deck cracking is described. The simulations conducted indicate that drying shrinkage appears to be capable of causing transverse (and possibly longitudinal) bridge deck cracks as early as 9 to II days after bridge deck placement. The drying-shrinkage induced stresses would result in transverse cracking over interior pier supports in a typical bridge superstructure …


Introductory Editorial: Water Microbiology, Patrick J. Mcnamara, Mark J. Krzmarzick Jan 2015

Introductory Editorial: Water Microbiology, Patrick J. Mcnamara, Mark J. Krzmarzick

Civil and Environmental Engineering Faculty Research and Publications

No abstract provided.


Visqolaudio: An Objective Audio Quality Metric For Low Bitrate Codecs, Andrew Hines, Eoin Gillen, Damien Kelly, Jan Skoglund, Anil Kokaram, Naomi Harte Jan 2015

Visqolaudio: An Objective Audio Quality Metric For Low Bitrate Codecs, Andrew Hines, Eoin Gillen, Damien Kelly, Jan Skoglund, Anil Kokaram, Naomi Harte

Articles

Streaming services seek to optimise their use of bandwidth across audio and visual channels to maximise the quality of experience for users. This letter evaluates whether objective quality metrics can predict the audio quality for music encoded at low bitrates by comparing objective predictions with results from listener tests. Three objective metrics were benchmarked: PEAQ, POLQA, and VISQOLAudio. The results demonstrate objective metrics designed for speech quality assessment have a strong potential for quality assessment of low bitrate audio codecs.


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 …


Tcd-Voip, A Research Database Of Degraded Speech For Assessing Quality In Voip Applications, Andrew Hines, Naomi Harte, Eoin Gillen Jan 2015

Tcd-Voip, A Research Database Of Degraded Speech For Assessing Quality In Voip Applications, Andrew Hines, Naomi Harte, Eoin Gillen

Conference papers

There are many types of degradation which can occur in Voice over IP calls. Degradations which occur independently of the codec, hardware, or network in use are the focus of this paper. The development of new quality metrics for modern communication systems depends heavily on the availability of suitable test and development data with subjective quality scores. A new dataset of VoIP degradations (TCD-VoIP) has been created and is presented in this paper. The dataset contains speech samples with a range of common VoIP degradations, and the corresponding set of subjective opinion scores from 24 listeners The dataset is publicly …


On A New Method For Interior Lighting Design, James Duff Jan 2015

On A New Method For Interior Lighting Design, James Duff

Doctoral

In 2009, Christopher Cuttle began to challenge the suitability of the metrics contained within current lighting design standards and guidance. In short, Cuttle proposed a move away from providing an amount of light that relates to the difficulty of a visual task and instead, providing an amount of light that relates to the brightness of a space. This sense of brightness would be estimated by a new lighting metric, Mean Room Surface Exitance. The research presented in this thesis strove to examine, critically evaluate, analyse and investigate the merit of changing indoor lighting standards to include Mean Room Surface Exitance. …


Enhanced Quality Of Experience Based On Enriched Network Centric And Access Control Mechanisms, Andreas Roos Jan 2015

Enhanced Quality Of Experience Based On Enriched Network Centric And Access Control Mechanisms, Andreas Roos

Doctoral

In the digital world service provisioning in user satisfying quality has become the goal of any content or network provider. Besides having satisfied and therefore, loyal users, the creation of sustainable revenue streams is the most important issue for network operators [1], [2], [3]. The motivation of this work is to enhance the quality of experience of users when they connect to the Internet, request application services as well as to maintain full service when these users are on the move in WLAN based access networks. In this context, the aspect of additional revenue creation for network operators is considered …


A Study Of The Impact Of Various Geometric Factors On The Capacity Of Short Range Indoor Mimo Communications Channels, Anthony Grennan Jan 2015

A Study Of The Impact Of Various Geometric Factors On The Capacity Of Short Range Indoor Mimo Communications Channels, Anthony Grennan

Doctoral

MIMO antenna array systems have been proposed as a means of increasing the spectral efficiency of wireless systems. However, their performance is likely to be sub-optimal if typical uniform antenna array structures are arbitrarily positioned; as they depend on spatial multiplexing. This is particularly true for indoor environments in which transmission ranges are short resulting in a strong correlation of the main propagation paths, especially the line-of-sight components. This makes it difficult to achieve successful spatial multiplexing which depends on a decorrelated set of signal components. Thus, the physical propagation channel and geometry of the antenna arrays, especially the inter-element …


Physics-Based Modeling And Control Of Powertrain Systems Integrated With Low Temperature Combustion Engines, Mehran Bidarvatan Jan 2015

Physics-Based Modeling And Control Of Powertrain Systems Integrated With Low Temperature Combustion Engines, Mehran Bidarvatan

Dissertations, Master's Theses and Master's Reports

Low Temperature Combustion (LTC) holds promise for high thermal efficiency and low Nitrogen Oxides (NOx) and Particulate Matter (PM) exhaust emissions. Fast and robust control of different engine variables is a major challenge for real-time model-based control of LTC. This thesis concentrates on control of powertrain systems that are integrated with a specific type of LTC engines called Homogenous Charge Compression Ignition (HCCI). In this thesis, accurate mean value and dynamic cycleto- cycle Control Oriented Models (COMs) are developed to capture the dynamics of HCCI engine operation. The COMs are experimentally validated for a wide range of HCCI steady-state and …


A Quantitative Investigation Of The Water Condensation Inside Tubes Of Compact Charge Air Cooler, Robin Cash Jan 2015

A Quantitative Investigation Of The Water Condensation Inside Tubes Of Compact Charge Air Cooler, Robin Cash

Dissertations, Master's Theses and Master's Reports

To address the need of increasing fuel economy requirements, automotive Original Equipment Manufacturers (OEMs) are increasing the number of turbocharged engines in their powertrain line-ups. The turbine-driven technology uses a forced induction device, which increases engine performance by increasing the density of the air charge being drawn into the cylinder. Denser air allows more fuel to be introduced into the combustion chamber, thus increasing engine performance. During the compression process, the air is heated to temperatures that can cause pre-ignition, resulting in reduced engine functionality. The introduction of the charge air cooler (CAC) is therefore, necessary to extract heat from …


Anthropomorphic Robotic Ankle-Foot Prosthesis With Active Dorsiflexion- Plantarflexion And Inversion-Eversion, Evandro Ficanha Jan 2015

Anthropomorphic Robotic Ankle-Foot Prosthesis With Active Dorsiflexion- Plantarflexion And Inversion-Eversion, Evandro Ficanha

Dissertations, Master's Theses and Master's Reports

The main goal of the research presented in this paper is the development of a powered ankle-foot prosthesis with anthropomorphic characteristics to facilitate turning, walking on irregular grounds, and reducing secondary injuries on bellow knee amputees. The research includes the study of the gait in unimpaired human subjects that includes the kinetics and kinematics of the ankle during different types of gait, in different gait speeds at different turning maneuvers. The development of a robotic ankle-foot prosthesis with two active degrees of freedom (DOF) controlled using admittance and impedance controllers is presented. Also, a novel testing apparatus for estimation of …


Blind Area Target Aiming System And Preference Selection Training System Design, Zhine Kang Jan 2015

Blind Area Target Aiming System And Preference Selection Training System Design, Zhine Kang

Dissertations, Master's Theses and Master's Reports

A cyber-physical system (CPS) is a system of leveraging computational elements controlling physical entities that is widely applied in our daily life for all kinds of purpose. It helps us build smart devices and make life become much easier. In this report, two projects were designed to show the idea that how cyber-physical system works in human daily life. The first project is designed for personal security, especially for one of the most dangerous job: security service. It helps user defend his back while he/she is in a tough situation while he or she is alone. First there will be …


Transient Thermoelectric Supercooling: Isosceles Current Pulses From A Response Surface Perspective And The Performance Effects Of Pulse Cooling A Heat Generating Mass, Alfred Piggott Jan 2015

Transient Thermoelectric Supercooling: Isosceles Current Pulses From A Response Surface Perspective And The Performance Effects Of Pulse Cooling A Heat Generating Mass, Alfred Piggott

Dissertations, Master's Theses and Master's Reports

With increased public interest in protecting the environment, scientists and engineers aim to improve energy conversion efficiency. Thermoelectrics offer many advantages as thermal management technology. When compared to vapor compression refrigeration, above approximately 200 to 600 watts, cost in dollars per watt as well as COP are not advantageous for thermoelectrics. The goal of this work was to determine if optimized pulse supercooling operation could improve cooling capacity or efficiency of a thermoelectric device. The basis of this research is a thermal-electrical analogy based modeling study using SPICE. Two models were developed. The first model, a standalone thermocouple with no …


Elementary Assessments And Simulations Based Proposals For New Heat Transfer Correlations And Flow Regime Maps For Annular/Stratified Regime Of Shear Driven Internal Condensing Flows, Siddharth Ravikumar Jan 2015

Elementary Assessments And Simulations Based Proposals For New Heat Transfer Correlations And Flow Regime Maps For Annular/Stratified Regime Of Shear Driven Internal Condensing Flows, Siddharth Ravikumar

Dissertations, Master's Theses and Master's Reports

Contemporary cooling applications necessitate the use of mm-scale shear driven flow condenser designs which also need to ensure substantial heat transfer rates for a wide range of flow conditions. Some modern shear driven flow condensers must meet the requirements of small size and large heat flux removal capability for variety of flow conditions. For this, effective estimates of heat transfer rate correlations and correlations for estimating the length of the annular regime are essential. Existing heat transfer correlations are built based on semi-empirical approaches which are primarily supported by large data sets, which are often mixed with insufficient explanation and …


An Assessment Of Polychlorinated Biphenyl Contamination In Fish From The Inland And Great Lakes Of Michigan, Emily Sokol Jan 2015

An Assessment Of Polychlorinated Biphenyl Contamination In Fish From The Inland And Great Lakes Of Michigan, Emily Sokol

Dissertations, Master's Theses and Master's Reports

Fish within the Great Lakes region of North America are an invaluable resource with economic and cultural significance. While these fish are vital, they contain chemical pollutants that are hazardous to human health. One such man-made group of chemicals, polychlorinated biphenyl compounds (PCBs), continue to be a problem long after the ban on production (1979).

The objective of this research thesis was to assess PCB contamination in fish within the Great Lakes Region. This objective was completed by determining the sources of PCB contamination, defining the ecosystem characteristics that significantly affect fish contamination, predicting when it will be safe to …


Perspectives On Environmental Management System Requirements, Raquel Taveras Jan 2015

Perspectives On Environmental Management System Requirements, Raquel Taveras

Dissertations, Master's Theses and Master's Reports

This report offers perspectives on effective environmental management procedures gained through field experience with the Peace Corps in Peru and with the United Nations Office for Project Services (UNOPS) in Copenhagen, Denmark. The work in Peru focused on case studies of rural water supply management within the context of local legislation and development strategies and environmental management principles. The objective of this study was to lay out a framework for future development workers and governmental agencies aiming to improve the administration and operation of rural water system. UNOPS on the other hand, as the operational arm of the UN for …


Kitchen 2.0: Investigation Of The Effect Of Ventilation On Indoor Air Quality, Kelli Marie Whelan Jan 2015

Kitchen 2.0: Investigation Of The Effect Of Ventilation On Indoor Air Quality, Kelli Marie Whelan

Dissertations, Master's Theses and Master's Reports

Even in today’s technology-filled world, nearly half of the global population still relies on some form of biomass to meet their daily energy requirement. Currently, improved combustion technologies (improved cookstoves) are the most common intervention to reduce fuel usage and to reduce human exposure to harmful products of incomplete combustion. This report explores an alternative option to cookstove replacement: ventilation as a low-cost, low-impact solution for health risk reduction.


Computational Study Of Microstructure-Propertymechanism Relations In Ferroic Composites, Fengde D. Ma Jan 2015

Computational Study Of Microstructure-Propertymechanism Relations In Ferroic Composites, Fengde D. Ma

Dissertations, Master's Theses and Master's Reports - Open

Ferroic materials, as notable members of smart materials, have been widely used in applications that perform sensing, actuation and control. The macroscopic property change of ferroic materials may become remarkably large during ferroic phase transition, leading to the fact that the macroscopic properties can be tuned by carefully applying a suitable external field (electric, magnetic, stress). To obtain an enhancement in physical and/or mechanical properties, different kinds of ferroic composites have been fabricated. The properties of a ferroic composite are determined not only by the properties and relative amounts of the constituent phases, but also by the microstructure of individual …


Extraction Of Pictorial Energy Information From Campus Unmetered Buildings Using Image Processing Techniques, Yachen Tang Jan 2015

Extraction Of Pictorial Energy Information From Campus Unmetered Buildings Using Image Processing Techniques, Yachen Tang

Dissertations, Master's Theses and Master's Reports - Open

In recent years, advanced metering infrastructure (AMI) has been the main research focus due to the traditional power grid has been restricted to meet development requirements. There has been an ongoing effort to increase the number of AMI devices that provide real-time data readings to improve system observability. Deployed AMI across distribution secondary networks provides load and consumption information for individual households which can improve grid management. Significant upgrade costs associated with retrofitting existing meters with network-capable sensing can be made more economical by using image processing methods to extract usage information from images of the existing meters. This thesis …


Advanced Computational Modeling Of The Internal Structure Of Smart Wind-Turbine Blades, Sanket Seetaram Bhogle Jan 2015

Advanced Computational Modeling Of The Internal Structure Of Smart Wind-Turbine Blades, Sanket Seetaram Bhogle

Dissertations, Master's Theses and Master's Reports - Open

Implementation of stable aeroelastic models with the ability to capture the complex features of Multi concept smartblades is a prime step in reducing the uncertainties that come along with blade dynamics. The numerical simulations of fluid structure interaction can thus be used to test a realistic scenarios comprising of full-scale blades at a reasonably low computational cost.

A code which was a combination of two advanced numerical models was designed and was run with the help of paralell HPC supercomputer platform. The first model was based on a variation of dimensional reduction technique proposed by Hodges and Yu. This model …


Improving Flow Distribution In Small-Scale Water-Supply Systems Through The Use Of Flow-Reducing Discs And Methods For Analyzing The Effectiveness Of Solar Powered Pumping For A Drinking Water Supply In Rural Panama, Briana I. Drake Jan 2015

Improving Flow Distribution In Small-Scale Water-Supply Systems Through The Use Of Flow-Reducing Discs And Methods For Analyzing The Effectiveness Of Solar Powered Pumping For A Drinking Water Supply In Rural Panama, Briana I. Drake

Dissertations, Master's Theses and Master's Reports - Open

As continued global funding and coordination are allocated toward the improvement of access to safe sources of drinking water, alternative solutions may be necessary to expand implementation to remote communities.

This report evaluates two technologies used in a small water distribution system in a mountainous region of Panama; solar powered pumping and flow-reducing discs. The two parts of the system function independently, but were both chosen for their ability to mitigate unique issues in the community. The design program NeatWork and flow-reducing discs were evaluated because they are tools taught to Peace Corps Volunteers in Panama.

Even when ample water …


A Market-Based Approach To 3d Printing For Economic Development In Ghana, Wade Aitken-Palmer Jan 2015

A Market-Based Approach To 3d Printing For Economic Development In Ghana, Wade Aitken-Palmer

Dissertations, Master's Theses and Master's Reports - Open

The purpose of this report is to create the foundation for further study of a market-based approach to 3D printing as an instrument for economic development in Ghana. The delivery of improved products and services to the most underserved markets is needed to spur economic activity and improve standards of living. The relationship between economic development and the advancement of technology is considered within the context of Ghana. An opportunity for market entry exists within both the bottom of the economic pyramid and the mid-segment market. 3D printing (additive manufacturing) has proven to be a disruptive technology that has demonstrated …


Water Use And System Reliability Under Dieselgenerator And Solar Photovoltaic Powered Pumping Systems: A Case Study Of Solla Togo, Alicia R. Sherrin Jan 2015

Water Use And System Reliability Under Dieselgenerator And Solar Photovoltaic Powered Pumping Systems: A Case Study Of Solla Togo, Alicia R. Sherrin

Dissertations, Master's Theses and Master's Reports - Open

Access to improved potable water sources is recognized as one of the key factors in improving health and alleviating global poverty. In recently years, substantial investments have been made internationally in potable water infrastructure projects, allowing 2.3 billion people to gain access to potable water from 1990-2012. One such project was planned and installed in Solla, Togo, a rural village in the northern part of the country, from 2010-2012. Ethnographic studies revealed that, while the community has access to potable water, an estimated 45% of the village’s 1500 residents still rely on unprotected sources for drinking and cooking. Additionally, inequality …


Improved Sensitivity Of Resonant Mass Sensor Based On Micro Tilting Plate And Micro Cantilever, Xiaoyu Song Jan 2015

Improved Sensitivity Of Resonant Mass Sensor Based On Micro Tilting Plate And Micro Cantilever, Xiaoyu Song

Dissertations, Master's Theses and Master's Reports - Open

Vapor sensors have been used for many years. Their applications range from detection of toxic gases and dangerous chemicals in industrial environments, the monitoring of landmines and other explosives, to the monitoring of atmospheric conditions. Microelectrical mechanical systems (MEMS) fabrication technologies provide a way to fabricate sensitive devices. One type of MEMS vapor sensors is based on mass changing detection and the sensors have a functional chemical coating for absorbing the chemical vapor of interest. The principle of the resonant mass sensor is that the resonant frequency will experience a large change due to a small mass of gas vapor …


Pose Estimation And 3d Reconstruction Using Sensor Fusion, Anuj S. Potnis Jan 2015

Pose Estimation And 3d Reconstruction Using Sensor Fusion, Anuj S. Potnis

Dissertations, Master's Theses and Master's Reports - Open

A camera maps 3-dimensional (3D) world space to a 2-dimensional (2D) image space. In the process it loses the depth information, i.e., the distance from the camera focal point to the imaged objects. It is impossible to recover this information from a single image. However, by using two or more images from different viewing angles this information can be recovered, which in turn can be used to obtain the pose (position and orientation) of the camera. Using this pose, a 3D reconstruction of imaged objects in the world can be computed. Numerous algorithms have been proposed and implemented to solve …