Engineering Commons^™

Study On The Methods For Predicting The Performance Of A Hybrid Solar-Assisted Ground-Source Heat Pump System, Zhaoyi Zhuang, Qiqi Zhu, Jian Song, Xin Zhang, Haorong Li

Durham School of Architectural Engineering and Construction: Faculty Publications

It is critical to find suitable setting parameters for designing a hybrid solar-assisted ground-source heat pump system in the practical engineering application, but the heat pump performance is unpredictable after many years of operation. This paper used 2000 sets of performance data collected from solar-assisted GSHP systems that keep operating over 20 years to simulate long term used heat pump with a professional software called GeoStar. Adopted the classification and regression tree (CART) method, the design of solar energy collector areas can be predicted. The multi-linear regression is also utilized to predict average monthly per meter borehole heat exchange. Seasonal …

Using Natural Language Processing And Machine Learning Techniques To Characterize Configuration Bug Reports: A Study, Wei Wen

Theses and Dissertations--Computer Science

In this study, a tool is developed that achieves two purposes: (1) given bug reports, it identifies configuration bug reports from non-configuration bug reports; (2) once a bug report is identified to be a configuration bug report, the tool finds out what specific configuration option the bug report is associated.

This study starts with a review of related works that used machine learning tools to solve software bug and bug report related issues. It then discusses the natural language processing and machine learning techniques. Afterwards, the development process of the proposed tool is described in detail, including the motivation, the …

Contributions To Edge Computing, Vernon K. Bumgardner

Theses and Dissertations--Computer Science

Efforts related to Internet of Things (IoT), Cyber-Physical Systems (CPS), Machine to Machine (M2M) technologies, Industrial Internet, and Smart Cities aim to improve society through the coordination of distributed devices and analysis of resulting data. By the year 2020 there will be an estimated 50 billion network connected devices globally and 43 trillion gigabytes of electronic data. Current practices of moving data directly from end-devices to remote and potentially distant cloud computing services will not be sufficient to manage future device and data growth.

Edge Computing is the migration of computational functionality to sources of data generation. The importance of …

Mammogram And Tomosynthesis Classification Using Convolutional Neural Networks, Xiaofei Zhang

Theses and Dissertations--Computer Science

Mammography is the most widely used method of screening for breast cancer. Traditional mammography produces two-dimensional X-ray images, while advanced tomosynthesis mammography produces reconstructed three-dimensional images. Due to high variability in tumor size and shape, and the low signal-to-noise ratio inherent to mammography, manual classification yields a significant number of false positives, thereby contributing to an unnecessarily large number of biopsies performed to reduce the risk of misdiagnosis. Achieving high diagnostic accuracy requires expertise acquired over many years of experience as a radiologist.

The convolutional neural network (CNN) is a popular deep-learning construct used in image classification. The convolutional process …

Modeling Faceted Browsing With Category Theory For Reuse And Interoperability, Daniel R. Harris

Theses and Dissertations--Computer Science

Faceted browsing (also called faceted search or faceted navigation) is an exploratory search model where facets assist in the interactive navigation of search results. Facets are attributes that have been assigned to describe resources being explored; a faceted taxonomy is a collection of facets provided by the interface and is often organized as sets, hierarchies, or graphs. Faceted browsing has become ubiquitous with modern digital libraries and online search engines, yet the process is still difficult to abstractly model in a manner that supports the development of interoperable and reusable interfaces. We propose category theory as a theoretical foundation for …

Precision Control Of Flow Rate In Microfluidic Channels Using Photoresponsive Soft Polymer Actuators, Colm Delaney, Peter Mccluskey, Simon Coleman, Jeffrey Whyte, Nigel Kent, Dermot Diamond

Articles

A novel approach that allows control of flow in microfluidic channels with unsurpassed performance using light is described. Valve structures have been created using photoresponsive hydrogels based on spiropyran-functionalised pNIPAAm hydrogels photopolymerised around pillar structures within the channels. Valve actuation is controlled from outside the fluidic system using externally located LEDs. Highly precise and accurate flow rates can be selected by passing real-time flow rate measurements into a PID algorithm. The optimised algorithm also minimises overshoot of the selected flow rate, eliminates flow rate drift, and improves the system response time. In addition to the dramatic improvements in flow rate …

Improved Subset Generation For The Mu-Decoder, Utsav Agarwal

LSU Master's Theses

The MU-Decoder is a hardware subset generator that finds use in partial reconfiguration of FPGAs and in numerous other applications. It is capable of generating a set S of subsets of a large set Z_n with n elements. If the subsets in S satisfy the “isomorphic totally- ordered property”, then the MU-Decoder works very efficiently to produce a set of u subsets in O(log n) time and Θ(n √u log n) gate cost. In contrast, a vain approach requires Θ(un) gate cost. We show that this low cost for the MU-Decoder can be achieved without the isomorphism constraint, thereby allowing …

Cuticle Accumulation Of Petrogenic Pahs On Spartina Alterniflora: A Novel Exposure Pathway For Marsh Biota, Joyce Gabriel Kassenga

LSU Master's Theses

Louisiana coastal marshes were heavily impacted by the 2010 Deepwater Horizon oil spill. MC252 oil pollution in coastal marshes lead to the exposure of biota to polycyclic aromatic hydrocarbons (PAHs). PAHs are persistent organic pollutants that can reside and accumulate in marsh biota. The aim of this study was to investigate the uptake mechanisms of PAHs by Spartina alterniflora at heavily oiled Bay Jimmy marsh in Barataria Basin, Louisiana. Study objectives were to quantify and investigate the uptake mechanisms of PAHs in the leaves of Spartina. The plant/air partitioning of PAHs was studied using a fugacity approach to determine their …

Novel Design And Synthesis Of Nanostructured Electrode Materials For Advanced Lithium Ion Batteries, Zhiqiang Xie

LSU Master's Theses

Nowadays, rechargeable lithium-ion batteries (LIBs) have been widely used as energy storage devices for portable electronic devices. The increasing demand for their emerging applications in hybrid electric vehicles (HEVs) and electric vehicles (EVs) requires us to develop LIBs with higher energy density and power density. However, both the commercial cathode material (LiCoO2) and anode material (graphite) exhibit low specific capacity and poor rate capability, which severely hinder the practical application of lithium-ion batteries for transportation. This thesis mainly includes four research works on novel design and synthesis of nanostructured electrode materials for advanced lithium-ion batteries. To improve the electrochemical performances …

Analysis Of Cost And Energy Performance Of Geothermal Heat Pump Systems In Southern Louisiana, Claudia De Lourdes Duran Tapia

LSU Master's Theses

In the last three decades of geothermal heat pump (GHP) industry, there has been an urge to present data, especially performance and itemized installation cost, as a plan to reduce the lack of knowledge and trust towards GHP systems for heating and cooling. The potential of GHPs in hot and humid climates is significant [Tao and Zhu, 2012]. However, past research efforts have demonstrated this potential through the use of simulation rather than real-time data. Therefore, the scope of work for this research is to investigate GHP system applications for residential buildings in areas with hot and humid climates. Based …

Network Performance Analysis Using Cisco Virl, Charitra Maharjan

LSU Master's Theses

This thesis provides a detailed analysis of the effects of TCP and UDP traffic over a LAN and WAN medium. In addition, it also analyses some real time applications like audio, video and web browsing that is affected by TCP traffic while sharing a bottleneck node and/or link resources. As network industry is growing continuously, the network administrator should be aware of TCP and UDP traffic that is traversing through their network. The analysis and monitoring of the traffic is crucial as it directly affects the performance of the network. Finding a cause for the poor performance of the network …

Characterization Of Hybrid Synthetic/Adipose-Derived Ecm Scaffolds, John Nicholas Poche

LSU Master's Theses

Evolving out of a need to address growing concerns regarding current methods of tissue transplantation, the field of tissue engineering seeks to facilitate the regeneration of viable tissue through the use of cellular scaffolds. The first aim of this thesis was to provide a summary of the current literature on advances in biomaterial synthesis and pertaining methods of stem cell delivery in tissue engineering. Improvements in the processing of decellularized tissue and the expansion of synthetic hydrogels as platforms for stem cell encapsulation have led to the development of extracellular matrix (ECM)-based hybrid hydrogels. These stem cell scaffolds are currently …

Unsteady Flow Simulations To Develop Model Scale Discharge Hydrographs For The Expanded Small Scale Physical Model Of The Mississippi River, Ronald Joseph Rodi

LSU Master's Theses

Small-scale HEC-RAS models were used to analyze discharges used to test the Louisiana State University and the Louisiana Coastal Protection & Restoration Authority Expanded Small Scale Physical Model (ESSPM) of the Mississippi River. The HEC-RAS models extend from River Mile 228.4 (Baton Rouge) to the Gulf of Mexico that includes the ESSPM reach which begins at River Mile 173.5 (Donaldsonville). The model scales are 1:6000 horizontally and 1:400 vertically. Using the historic river discharges from 2008 through 2015, the small-scale numerical models proved capable of replicating observed stages along eleven sites of the lower Mississippi River within the targets of …

Method For Quantifying Floating Marsh Strength And Interaction With Hydrodynamics, Jason Haydel Collins Iii

LSU Master's Theses

Louisiana possesses over 350,000 acres of unique floating vegetated systems known as floating marshes or flotants. Due to their buoyant nature, floating marshes are susceptible to high energy changes in the hydrodynamic environment that may result from proposed river diversion projects which introduce flow to areas that are typically somewhat isolated. The overall goal of this research is to improve the understanding of how exposed flotants deteriorate under increased hydrodynamic stresses. More specifically, this thesis aims to answer how the material limits of floating marshes can be measured and how the mats interact with hydrodynamics. The two primary objectives are: …

The Effects Of Different Spinal Fusion Instrumentation On Thoracic Vertebrae: A Parametric Finite Element Study, Thomas Henry Ballard

All ETDs from UAB

Proximal junction kyphosis is a condition that can occur after a long spinal fusion, typically seen in deformity correction surgery. Patients are said to exhibit proximal junc-tion kyphosis when the angle between the uppermost instrumented vertebra and two ver-tebra above that is greater than 10°. Proximal junction kyphosis does not always lead to another surgery but can progress and become symptomatic causing pain and discomfort. Symptomatic proximal junction kyphosis is referred to as proximal junction failure, char-acterized by degradation of the adjacent intervertebral disc or collapse of the proximal vertebral body. It is believed that proximal junction kyphosis/failure arises from …

Towards Improving Visqol (Virtual Speech Quality Objective Listener) Using Machine Learning Techniques, Joseph Mcnally

Dissertations

Vast amounts of sound data are transmitted every second over digital networks. VoIP services and cellular networks transmit speech data in increasingly greater volumes. Objective sound quality models provide an essential function to measure the quality of this data in real-time. However, these models can suffer from a lack of accuracy with various degradations over networks. This research uses machine learning techniques to create one support vector regression and three neural network mapping models for use with ViSQOLAudio. Each of the mapping models (including ViSQOL and ViSQOLAudio) are tested against two separate speech datasets in order to comparatively study accuracy …

Critical Comparison Of The Classification Ability Of Deep Convolutional Neural Network Frameworks With Support Vector Machine Techniques In The Image Classification Process, Robert Kelly

Dissertations

Recently, a number of new image classification models have been developed to diversify the number of options available to prospective machine learning classifiers, such as Deep Learning. This is particularly important in the field of medical image classification as a misdiagnosis could have a severe impact on the patient. However, an assessment on the level to which a deep learning based Convolutional Neural Network can outperform a Support Vector Machine has not been discussed. In this project, the use of CNN and SVM classifiers is used on a dataset of approx. 55,000 images. This dataset was used to assess the …

Impact Of Us Low Cost Carriers Entrance To The Airline Market In Colombia, South America, Carolina Anderson, Tamilla Curtis, Robert F. Moss, Maryjo O. Smith, Gerson Mey

International Journal of Aviation, Aeronautics, and Aerospace

This study researched the impact of US low cost carriers’ entrance to the airline market in Colombia, South America. The study analyzed the overall market share between Florida and Colombia after U.S. low cost carriers entered the market and finds that the market share for the Colombian flag carrier Avianca and U.S. legacy carrier American Airlines, who used to dominate this market, has decreased; however, the total passenger demand has increased. This increase in passenger demand can be attributed in part to U.S. low cost carriers opening new city pairs and allowing passengers to fly direct to the U.S. from …

Long And Short-Range Air Navigation On Spherical Earth, Nihad E. Daidzic

International Journal of Aviation, Aeronautics, and Aerospace

Global range air navigation implies non-stop flight between any two airports on Earth. Such effort would require airplanes with the operational air range of at least 12,500 NM which is about 40-60% longer than anything existing in commercial air transport today. Air transportation economy requires flying shortest distance, which in the case of spherical Earth are Orthodrome arcs. Rhumb-line navigation has little practical use in long-range flights, but has been presented for historical reasons and for comparison. Database of about 50 major international airports from every corner of the world has been designed and used in testing and route validation. …

An Exploration Study Of Using The Universities Performance And Enrolments Features For Predicting The International Quality, Aeshah Althagafi

Dissertations

Quality ranking systems are crucial in the assessment of the academic performance of an institution because these assessment systems give details about how different learning institutions deliver their services. Education quality is also of paramount importance to the students because it is through quality education that these students develop skills that are needed in the job market. Besides, education enhances a student's academic and reasoning capacities. When universities are subjected to ranking systems, they are likely to improve their quality to be ranked high in the system. When the university administrators are exposed to ranking, competition gears up. Through competition, …

Exploring The Factors That Affect Secondary Student’S Mathematics And Portuguese Performance In Portugal, Lulu Cheng

Dissertations

Secondary education provides not only knowledge and skills, but also inculcates values, training of instincts, fostering right attitude and habits to enable adolescents to move into tertiary education or to ensure a workplace for students who decided to terminate their secondary schooling. Without secondary education to guide the development of young people through their adolescence, they will be ill prepared for tertiary education or for workplace, moreover, the possibility of juvenile delinquency and teenage pregnancy becomes higher. These negative effects will increase the pressures and expenditures on society and socio-economic. In 2006, Portugal was reported having the higher school-leaving rate …

The Influence Of Sensor-Based Intelligent Traffic Light Control On Traffic Flow In Dublin, Katja Rademacher

Dissertations

With growing cities and the increased use of vehicles for transportation purposes, there is a demand to make the traffic management in cities smarter. An intelligent traffic light control that dynamically adapts to the existing traffic conditions can help reduce traffic congestion and CO2 emissions. This thesis reviews the popular traffic light control approaches - static, actuated and adaptive – based on their influences on recorded traffic conditions in Dublin. The Irish capital relies heavily on busses for public transport adding to the number of already moving vehicles in the city centre. Using vehicle count data from inductive loop detectors …

Physical Human Activity Recognition Using Machine Learning Algorithms, Haritha Vellampalli

Dissertations

With the rise in ubiquitous computing, the desire to make everyday lives smarter and easier with technology is on the increase. Human activity recognition (HAR) is the outcome of a similar motive. HAR enables a wide range of pervasive computing applications by recognizing the activity performed by a user. In order to contribute to the multi facet applications that HAR is capable to offer, predicting the right activity is of utmost importance. Simplest of the issues as the use of incorrect data manipulation or utilizing a wrong algorithm to perform prediction can hinder the performance of a HAR system. This …

Application Of Supervised Machine Learning To Predict The Mortality Risk In Elderly Using Biomarkers, Priyanka Sonkar

Dissertations

The idea of long-term survival amongst older individuals has been a major medical and social concern. A wide range of biomarkers have been identified to prospectively predict disability, morbidity, and mortality outcomes in older adult populations. The machine learning techniques applied with clinically relevant biomarkers provide new ways of understanding diseases and solutions to tackle challenges to the health of the aging population. This paper describes two supervised machine learning techniques, Logistic Regression (LR) and Support Vector Machine (SVM) which are used in the prediction of the mortality in elderly people. LR is one of the traditionally used predictive modeling …

Modeling Mortgage Assessment With Computational Argumentation Theory And Defeasible Reasoning, Henrik Szucs

Dissertations

In the mortgage lending business of a bank, a key focus area is risk analysis, which supports the mortgage awarding process and the prediction of the risk of defaulting (repayment issues). The standard risk assessment method at most banks is a scorecard calculation. A new way of predicting the defaulting is proposed using Defeasible Reasoning (DR) and computational Argumentation Theory (AT), areas of interdisciplinary research, in the discipline of Articial Intelligence (AI). Argumentation is formalised by reasoning models which are inspired by human reasoning. For a more realistic representation AT employs DR which is a non-monotonic reasoning process, meaning that …

The Evaluation And Implementation Of Magnetic Fields Suitable For Biaxial Cyclic Testing Of Magnetorheological Elastomers, Dave Gorman

Doctoral

This thesis addresses the current lack of specification of magnetic fields currently used in the physical testing of Magnetorheological Elastomers MREs as well as providing the first comparative test results for MREs subject to both biaxial and uniaxial cyclic loading in the same magnetic field. In order to design an electromagnetic array capable of generating a suitable magnetic field for the cyclic biaxial testing of MREs, a review of currently used magnetic fields for uniaxial testing of MREs was carried out and a suitable array was modelled and evaluated with both 2D and 3D FEA software. Once the FEA analysis …

Oxygen Transport In Carotid And Stented Coronary Arteries, Eoin A. Murphy

Doctoral

Oxygen deficiency, known as hypoxia, in arterial walls has been linked to increased intimal hyperplasia, which is the main adverse biological process causing in-stent restenosis. Stent implantation can have significant effects on the oxygen transport into the arterial wall. Helical flow has been theorised to improve the local haemodynamics and the oxygen transport within stented arteries. In this study an advanced oxygen transport model was developed to assess different stent designs. This advanced oxygen transport model incorporates both the free and bound oxygen contained in blood and includes a shear-dependent dispersion coefficient for red blood cells. In two test cases …

Quantitative Estimation Of Causality And Predictive Modeling For Precipitation Observation Sites And River Gage Sensors, Tri Vu Nguyen

LSU Master's Theses

This project seeks to investigate two questions: correlations from precipitation measurement sensors to river gage sensors, and predictive modeling of peak river gage heights during precipitation events. First, if correlations can be quantified, then a predictive model can be explored to predict peak water levels at river gage sensors, in response to precipitation inputs. Answering both research questions can provide early flood detection benefits and provide quantitative time assessments for flood risks. An extensive data-driven study was conducted across a geographical area of the U.S, spanning the time period 2008-2016 to identify river gage sensors that are closely correlated to …

Selecting Sensors When Forecasting Temperature In Smart Buildings, Bruce Spencer, Feras Al-Obeidat, Omar Alfandi

All Works

© 2017 The Authors. Published by Elsevier B.V. Forecasts of temperature in a "smart" building, i.e. one that is outfitted with sensors, are computed from data gathered by these sensors. Model predictive controllers can use accurate temperature forecasts to save energy by optimally using Heating, Ventilation and Air Conditioners while achieving comfort. We report on experiments from such a house, in which we select different sets of sensors, build a temperature model from each set, and then compare the accuracy of these models. While a primary goal of this research area is to reduce costs by reducing energy consumption, in …

Risk Registers: Structuring Data Collection To Develop Risk Intelligence, Maria Chiara Leva, Nora Balfe, B. Mcaleer, M. Rock

Articles

This paper presents the results of the development and implementation of a company-wide risk register, based on a clear set of data structures. A case study from an electricity generation company is presented and the process followed is described. The results of the case study indicated areas where the concept of risk registers could be extended to make better use of existing data and to support continuous improvement of risk management. Six key areas are discussed (1) aggregation of risks across the business, (2) supporting controls over mitigation measures, (3) improved estimation of event likelihood, (4) integrating with critical asset …