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Full-Text Articles in Engineering

Coupled Oscillators: Protein And Acoustics, Angelique N. Mcfarlane Aug 2022

Coupled Oscillators: Protein And Acoustics, Angelique N. Mcfarlane

Theses

This work encompassed three different vibrational energy transfer studies of coupled resonators (metal, topological, and microtubule comparison) inspired by the lattices of microtubules from regular and cancerous cells. COMSOL Multiphysics 5.4 was utilized to design the experiment. The simulation starts with an acoustic pressure study to examine the vibrational modes present in coupled cylinders, representing α-, β-tubulin heterodimers. The Metal Study consisted of 3 models (monomer, dimer, and trimer) to choose the correct height (40 mm) and mode (Mode 1) for study. The Topological Study was run to predict and understand how the lattice structure changes over a parametric sweep …


Un-Fair Trojan: Targeted Backdoor Attacks Against Model Fairness, Nicholas Furth May 2022

Un-Fair Trojan: Targeted Backdoor Attacks Against Model Fairness, Nicholas Furth

Theses

Machine learning models have been shown to be vulnerable against various backdoor and data poisoning attacks that adversely affect model behavior. Additionally, these attacks have been shown to make unfair predictions with respect to certain protected features. In federated learning, multiple local models contribute to a single global model communicating only using local gradients, the issue of attacks become more prevalent and complex. Previously published works revolve around solving these issues both individually and jointly. However, there has been little study on the effects of attacks against model fairness. Demonstrated in this work, a flexible attack, which we call Un-Fair …


Design And Implementation Of Photovoltaic Energy Harvesting Automaton, Iskandar Askarov Jan 2022

Design And Implementation Of Photovoltaic Energy Harvesting Automaton, Iskandar Askarov

Theses

Global domestic electricity consumption has been rapidly increasing in the past three decades. In fact, from 1990 to 2020, consumption has more than doubled from 10,120 TWh to 23,177 TWh [1]. Moreover, consumers have been turning more towards clean, renewable energy sources such as Photovoltaic. According to International Energy Agency, global Solar power generation alone in 2019 has reached almost 3% [4] of the electricity supply. Even though the efficiency of photovoltaic panels has been growing, presently, the highest efficiency solar panels available to an average consumer range only from 20%-22% [14]. Many research papers have been published to increase …


Environmental Assessment Of The Impact Of Land-Based Discharges On Marine Water And Sediment Quality In Dubai, Uae, Ayman Fathy Halawa Sep 2021

Environmental Assessment Of The Impact Of Land-Based Discharges On Marine Water And Sediment Quality In Dubai, Uae, Ayman Fathy Halawa

Theses

The current seawater and Creek – Canal waterway in the Emirate of Dubai, UAE, is under tremendous pressure because of continuous urban water discharges from land-based sources. Therefore, the impact of urban water discharges on marine water and sediment quality in the Emirate requires a thorough assessment. The main objective of this study is to assess the impacts of effluent discharges on the quality of water and sediment in the open sea and Dubai Creek. The land-based sources include the power and desalination plants, industrial sector, sewage treatment plant, and stormwater runoff. To achieve the stated objective, relevant data on …


Treated Hfo2 Based Rram Devices With Ru, Tan, Tin As Top Electrode For In-Memory Computing Hardware, Yuvraj Dineshkumar Patel Dec 2020

Treated Hfo2 Based Rram Devices With Ru, Tan, Tin As Top Electrode For In-Memory Computing Hardware, Yuvraj Dineshkumar Patel

Theses

The scalability and power efficiency of the conventional CMOS technology is steadily coming to a halt due to increasing problems and challenges in fabrication technology. Many non-volatile memory devices have emerged recently to meet the scaling challenges. Memory devices such as RRAMs or ReRAM (Resistive Random-Access Memory) have proved to be a promising candidate for analog in memory computing applications related to inference and learning in artificial intelligence. A RRAM cell has a MIM (Metal insulator metal) structure that exhibits reversible resistive switching on application of positive or negative voltage. But detailed studies on the power consumption, repeatability and retention …


Comparison Of Longitudinal Changes In Resting State Functional Magnetic Resonance Imaging Between Alzheimer’S And Healthy Controls, Berk Can Yilmaz Aug 2020

Comparison Of Longitudinal Changes In Resting State Functional Magnetic Resonance Imaging Between Alzheimer’S And Healthy Controls, Berk Can Yilmaz

Theses

Resting State Functional Magnetic Resonance Imaging (rs-fMRI) is a technique that is widely used for analyzing brain function using different approaches and methods. This study involves rs-fMRI analysis of Blood Oxygenation Level Dependent (BOLD) signals acquired from Alzheimer’s disease (AD) Patients and Healthy Controls (HC). Each subject in the study had both functional and anatomical images with at least one rs-fMRI scan with their Anatomical (T1) scans. Previous rs-fMRI studies have demonstrated that AD shows differences in Amplitude of Low Frequency (<0.1 Hz) Fluctuations (ALFF), and Regional Homogeneity (ReHo) measures according to HCs.

The aim of the study is to investigate individual and group level differences using ReHo and mALFF related …


Model-Based Deep Siamese Autoencoder For Clustering Single Cell Rna-Seq Data, Zixia Meng May 2020

Model-Based Deep Siamese Autoencoder For Clustering Single Cell Rna-Seq Data, Zixia Meng

Theses

In the biological field, the smallest unit of organisms in most biological systems is the single cell, and the classification of cells is an everlasting problem. A central task for analysis of single-cell RNA-seq data is to identify and characterize novel cell types. Currently, there are several classical methods, such as K-means algorithm, spectral clustering, and Gaussian Mixture Models (GMMs), which are widely used to cluster the cells. Furthermore, typical dimensional reduction methods such as PCA, t-SNE, and ZIDA have been introduced to overcome “the curse of dimensionality”. A more recent method scDeepCluster has demonstrated improved and promising performances in …


Passive Cooling In Non-Residential Nearly Zero Energy Buildings: A Thermal Comfort Analysis Based On Measurement, Modelling And Simulation, Adam O'Donovan Jan 2019

Passive Cooling In Non-Residential Nearly Zero Energy Buildings: A Thermal Comfort Analysis Based On Measurement, Modelling And Simulation, Adam O'Donovan

Theses

Overheating in non-residential nearly zero energy buildings (nZEBs) presents a major risk to the well-being, productivity and thermal satisfaction of the people who occupy them. As global temperatures are expected to increase in the future, the overheating risk and cooling demand is also expected to increase. Therefore, low cost and low energy solutions that are able to maintain thermally comfortable conditions without the need for mechanical systems will be vital in decarbonising the building stock and ensuring that buildings are comfortable and remain low carbon now and in the future. Passive cooling has long been championed as a low cost …


Predicting Energy And Water Consumption On Dairy Farms Through Statistical Analysis And Machine-Learning Methods, Philip Shine Jan 2018

Predicting Energy And Water Consumption On Dairy Farms Through Statistical Analysis And Machine-Learning Methods, Philip Shine

Theses

With the abolishment of milking quotas across all European Union member states in April 2015, dairy farmers must adjust their farming practises to minimise milk production costs to adequately prepare for potential periods of reduced revenue. Milk production is an intense energy and water consuming process. Coupled with challenging European greenhouse gas reduction targets and legislation regarding the prevention of groundwater pollution and deterioration, increasing the production of milk in Ireland must be met with the sustainable consumption of on-farm energy and direct water resources, to ensure the future monetary and environmental sustainability of Ireland’s dairy industry. Thus, this body …


Development Of A Dynamic Cfd Model For Offshore Oscillating Water Columns With Non-Linear Interactions, Ken O'Connell Jan 2017

Development Of A Dynamic Cfd Model For Offshore Oscillating Water Columns With Non-Linear Interactions, Ken O'Connell

Theses

This thesis focuses on the development of a state of the art modelling technique for offshore Oscillating Water Column (OWC) type Wave Energy Converters (WEC) using Computational Fluid Dynamics (CFD). Current literature indicates a limited amount of work has been completed on studying these devices containing non-linear time dependent flow phenomenon. Initially, a 2D Numerical Wave Tank (NWT) is studied to reduce discretisation error in order to reproduce accurately propagating waves. Further development into a 3D domain permits the geometrical requirements of an OWC type spar buoy to be included.

In parallel, a single Degree of Freedom (DOF) model is …


Semiconductor Materials And Devices For 2 Micron Generation, Dzianis Saladukha Jan 2017

Semiconductor Materials And Devices For 2 Micron Generation, Dzianis Saladukha

Theses

In the last century, semiconductor research has led to significant changes in the fields of communication, medicine, the environment, and many others. Semiconductor devices provide a relatively simple and effective way to convert electrical energy to light and vice versa. Devices based on semiconductor materials of various kinds provide interaction of an electromagnetic signal in the range of wavelengths with a medium. Examples of such devices are LED lamps, photovoltaic cells, thermometers, gas sensors, cameras, and many others. The study of various semiconductors broadens the range of application of photonics. This work is based on the study of materials which …


A Decision Making Tool For Sustainable Design In Construction, Enda Collins Jan 2014

A Decision Making Tool For Sustainable Design In Construction, Enda Collins

Theses

This report defines sustainability and sustainable development before any research is carried out. This is necessary so that the research carried out further in the report makes sense and there is a reason for including such items in this report. The need for this project and what the project aims to achieve is also highlighted in the introduction of this report.

Sustainability is made up of three equal parts; social, economic and environmental. This report goes through each item and gives examples of each type of development. Having discussed sustainability in a broad sense the report then focuses on Legislation …


Achieving ‘Net Zero Energy’ Performance Through Retrofitting Of Residential Buildings In Ireland., M. Alan Costello Jan 2014

Achieving ‘Net Zero Energy’ Performance Through Retrofitting Of Residential Buildings In Ireland., M. Alan Costello

Theses

A Net Zero Energy Building (nZEB) is a residential or commercial building that consumes net zero energy over a set period of time, usually taken as one year. In short, for every unit of energy the building consumes over a year, it must generate a unit of energy to maintain an overall net balance. This is achieved by reducing the operational energy usage to a very low level through energy efficient design, and then providing renewable generation technologies on site to cater for the remaining energy demand.

Energy use in all sectors of society is under scrutiny at present, largely …


Segmentation And Model Generation For Large-Scale Cyber Attacks, Steven E. Strapp Aug 2013

Segmentation And Model Generation For Large-Scale Cyber Attacks, Steven E. Strapp

Theses

Raw Cyber attack traffic can present more questions than answers to security analysts. Especially with large-scale observables it is difficult to identify which packets are relevant and what attack behaviors are present. Many existing works in Host or Flow Clustering attempt to group similar behaviors to expedite analysis; these works often phrase the problem directly as offline unsupervised machine learning. This work proposes online processing to simultaneously model coordinating actors and segment traffic that is relevant to a target of interest, all while it is being received. The goal is not just to aggregate similar attack behaviors, but to provide …


Investigation Of Wastewater Treatment Plant Sustainability Potential In Terms Of Resource Recovery Essentials, Aoife Moloney Jan 2013

Investigation Of Wastewater Treatment Plant Sustainability Potential In Terms Of Resource Recovery Essentials, Aoife Moloney

Theses

This thesis aims to explore the sustainability potential which exists in Wastewater Treatment Plants (WWTP's); particularly focusing on nutrient, energy, and water recovery and reuse. The core of the research will focus on the establishment of a sustainable Resource Recovery Treatment Plant (RRTP) plan for Limerick Main Drainage (LMD) WWTP, and potentially utilising this as a case study plant which could act as a foundation example within the sector.

There is a genuine need to investigate more sustainable options in wastewater treatment (WWT); increasing energy and sludge management costs are a real issue for non-sustainable WWTP's given that thousands of …


Visualising Urban Flooding Scenarios Using Video Game Technology, William Elliott Lynn Jan 2012

Visualising Urban Flooding Scenarios Using Video Game Technology, William Elliott Lynn

Theses

This thesis investigates the application of computer graphics to the visualisation of urban flooding scenarios. The demand for urban flooding visualisations is presented in the context of an EU wide climate change response strategy. An analysis of the requirements from various stakeholders is presented and a strategy that addresses these requirements is synthesised. A study on the appropriate computer graphics methods and technologies is outlined and limitations of current technologies are assessed. Systems that solve these limitations are described and the result of usability and user acceptance testing are offered as evidence.


Semi-Automatic Management Of Knowledge Bases Using Formal Ontologies, Andreas Textor Jan 2011

Semi-Automatic Management Of Knowledge Bases Using Formal Ontologies, Andreas Textor

Theses

This thesis presents an approach that deals with the ever-growing amount of data in knowledge bases, especially concerning knowledge interoperability and formal representation of domain knowledge. There arc multiple issues that must be addressed with current systems. A multitude of different formats, sources and tools exist in a domain, and it is desirable to develop their use further towards a standardised environment. Such an environment should support both the representation and processing of data from this domain, and the connection to other domains, where necessary. In order to manage large amounts of data, it should be possible to perform whatever …


Design Of A Centralised Anaerobic Digestion Plant In Ireland., Diarmuid O'Meara Jan 2011

Design Of A Centralised Anaerobic Digestion Plant In Ireland., Diarmuid O'Meara

Theses

Climate change is brought about by greenhouse gases emitted to the earth’s atmosphere by fossil fuels. Renewable energy sources are seen as an alternative to fossil fuels. Examples of renewable energy sources are biofuels which are a method of reducing the emission of greenhouse gases. One form of biofuels is biogas that is produced during the anaerobic digestion process. In this thesis pig slurry is used to produce biogas.

In this project, the optimum design process for a centralised anaerobic digestion plant was established in the literature review, The optimum process for anaerobic digestion plant design in Ireland was investigated. …


Automated Network Planning For Industrial Ethernet Networks, Holger Machens Jan 2009

Automated Network Planning For Industrial Ethernet Networks, Holger Machens

Theses

Engineers usually use computer aided methods to ease the increasingly complex planning task of automation plants. One such computer aided method for automated planning of Industrial Ethernet networks under given network QoS requirements is presented in this thesis. The method is based on partitioning the given set of network nodes according to specified communication relationships between the nodes, thereby creating subsets of nodes which are joined using given networking algorithms. Several networking algorithms may be applicable for each subset of nodes and any complete solution is a combination of several partial solutions, one for each subset of nodes. Enumeration through …


Lightweight Objective Quality Of Voice Estimation Through Machine Learning, Daniel Riordan Jan 2008

Lightweight Objective Quality Of Voice Estimation Through Machine Learning, Daniel Riordan

Theses

Communication systems are undergoing constant and rapid innovation, both at the design stage and in the field. This in turn has led to an inereasing need for fast, efficient, portable and economic methods for the testing of these systems. For voice carrying communication systems the quality of the transmitted voice that the system produces is a large factor in the overall performance rating of the system. This measure is known as the ‘Quality of Voice’ (QoV) and can be evaluated either subjectively or objectively.

Speech quality is a complex subjective phenomenon that can be best quantified by subjective testing. A …


Optimization In Multi-Agent Systems : Structures And Procedures, Ingo Stengel Jan 2008

Optimization In Multi-Agent Systems : Structures And Procedures, Ingo Stengel

Theses

The main advantage for the use of agent technology is in the capacity of agents to represent the interests of individual entities and to act autonomously on their behalf. In multi-agent systems this involves communication, coordination and negotiation.

The focus of this dissertation is to find ways to optimize multi-agent systems at different levels by taking into consideration their structure and the procedures used. As optimization depends to a large extent on the problem to be solved, group forming scenarios, in which self-interested agents compete to form and join groups, have been selected here for consideration. Optimization issues are discussed …


Elliptic Curve Cryptography Security On Restricted Mobile Devices, Debbie Mccann Jan 2008

Elliptic Curve Cryptography Security On Restricted Mobile Devices, Debbie Mccann

Theses

Mobile technologies with limited resources, such as smart phones or PDAs, have increased dramatically in popularity. However, the level of security provided for these technologies has not kept pace with the value of the data that they contain or transmit.

Wireless networks usually provide some security, in the form of encryption. GSM and GPRS use different forms of the A5 algorithm, and Wi-Fi uses WEP or WPA. These encryption algorithms have proven weaknesses and in some cases have been efficiently cracked. To improve the security of wireless networks, stronger encryption algorithms need to be developed. One of the most attractive …


Management Framework For Hybrid Wireless Networks, Chong Shen Jan 2008

Management Framework For Hybrid Wireless Networks, Chong Shen

Theses

The objective of the Hybrid Wireless Network with dedicated Relay Nodes (HWN*) architecture is to interface the Base Station (BS) Oriented Mobile Network (BSON) and the 802.fix based Mobile Ad hoc Wireless Network (MANET) so that one system can be utilised as an alternative radio access network for data transmissions, while the incorporation of Relay Nodes (RN) is to extend the communication coverage, optimise medium resource sharing, increase spatial reuse opportunity, stabilise MANET link and create more micro-cells. The HWN* keeps the existing cellular infrastructure and a Mobile Terminal (MT) can borrow radio resources from other cells via secure multi-hop …


A Distributed Ai Approach For Large-Scale Wlan Design, Alan Mcgibney Jan 2008

A Distributed Ai Approach For Large-Scale Wlan Design, Alan Mcgibney

Theses

The recent dramatic trend towards always-on-connectivity has driven the need for mobile ubiquitous computing environments with the advent of the Wireless Local Area Network (WLAN) seeing a shift from traditional wired networks to wireless networking. A WLAN typically contains a number of access points that allow wireless enabled clients access information and network resources such as the internet without the need for wires, offering flexibility and mobility to the users. Initial wireless networks were convenience based allowing users access to the primary wired network, and involved little planning prior to roll-out. The proliferation of low cost wireless devices combined wdth …


Personal Information Management. A Framework For Development Of Personalisable Web Based Services, Christopher Fuchs Jan 2007

Personal Information Management. A Framework For Development Of Personalisable Web Based Services, Christopher Fuchs

Theses

The thesis research proposed herein will model, analyse and implement strategies for the development of personalised services. The goal of the research work is to design and implement a framework which supports developers by minimising the effort required in implementing personalised services. This includes the ability to react to localisation changes and to present proper information. An overall design goal is the independency of most components from each other which will be attained through the use of standard technologies and protocols and the consistent use of a component model. The result will include the proposed framework and the analyses of …


Anaerobic Digestion: Decision Support Software, Marco Poliafico Jan 2007

Anaerobic Digestion: Decision Support Software, Marco Poliafico

Theses

Ireland has significant quantities of livestock; meat exportation is a vibrant sector of the economy. Environmental management of animal wastes has therefore become an important concern. On the other hand in the last decade, national and EU policy debate has highlighted the need to investigate alternative energy: in particular energy for transport.

This study investigates the quantities of animal wastes produced in Ireland and their potential treatment using Anaerobic Digestion technologies. In 2005 Ireland had over 8 millions animals (cattle and pigs) and the annual slaughter accounted for over 4.2 million of these creatures. These animals have been responsible for …


The Potential For Ch4-Enriched Biogas As A Transport Fuel In Ireland, Niamh Power Jan 2007

The Potential For Ch4-Enriched Biogas As A Transport Fuel In Ireland, Niamh Power

Theses

Ireland needs a biofuel industry- to aid compliance with the Kyoto Protocol, the Biofuels Directive and to secure its energ>' supply. The overall aim of this work is to assess the potential of CH4-enriched biogas as a transport fuel in Ireland. Biogas is produced during the anaerobic digestion of biomass. This work investigates biogas production from two different feedstocks; biodegradable municipal waste and agricultural crops. To assess the potential for biogas as a transport fuel the alternatives to biogas are investigated and compared. Thus digestion and composting of biodegradable municipal waste, and biogas and ethanol production from agricultural crops …


Development Of A Service-Oriented Communication Platform For Heterogeneous Voice Over Ip Networks., Aisling O'Driscoll Jan 2006

Development Of A Service-Oriented Communication Platform For Heterogeneous Voice Over Ip Networks., Aisling O'Driscoll

Theses

As broadband services have become more widespread in recent years due to a variety of government initiatives and the establishment of Wireless Internet Service Providers, user requirements have evolved and the market has become more competitive. Whilst this is beneficial for consumers it means that Internet Service Providers must offer a more diverse range of services coupled with standard broadband packages to distinguish themselves from their competitors, generate new revenue and strengthen their competitive advantage. Therefore many providers are looking to Service Oriented Architectures (SOAs) to provide communication platforms, enabling services such as Voice over IP (VoIP) along with other …


Numerical Modelling Of Sediments In Cork Harbour, Jérémy Pingon Jan 2005

Numerical Modelling Of Sediments In Cork Harbour, Jérémy Pingon

Theses

In recent years there have been considerable developments in the new and emerging field of hydroinformatics. This relatively new discipline is concerned with the application of computer and networking technology for the planning, management and protection of water bodies.

Environmental issues in estuaries require accurate and detailed knowledge of cohesive sediment transport processes to assess different issues including water quality, pollutant dispersion, and dredging and maintenance of navigation channels.

This thesis presents a review of the main sediment properties and processes required for modelling the behaviour and transport of sediments. It also introduces a new approach to sediment properties using …


Optimisation Of Heat Transfer And Fluid Flow In The Cooling Of Building Integrated Photovoltaic Facades., Eoin Patrick Hodge Jan 2004

Optimisation Of Heat Transfer And Fluid Flow In The Cooling Of Building Integrated Photovoltaic Facades., Eoin Patrick Hodge

Theses

The aim of this research was to explore the effects of mature and developing technologies from aeronautical industries such as impingement and film cooling, and electronic cooling techniques, in the setting up of different laminar and turbulent flow regimes on PV cooling duct heat transfer rates, with air flow as that brought about with natural buoyancy effects in a vertical building facade. The problem of efficiency losses in PV panels, due to overheating, is one of the factors restricting the development and use of this renewable power source. PV panels can experience very high temperatures, due to the heat input …