Engineering Commons^™

An Empirical Comparison Of The Security And Performance Characteristics Of Topology Formation Algorithms For Bitcoin Networks, Muntadher Sallal, Ruairí De Fréin, Ali Malik, Benjamin Aziz

Articles

There is an increasing demand for digital crypto-currencies to be more secure and robust to meet the following business requirements: (1) low transaction fees and (2) the privacy of users. Nowadays, Bitcoin is gaining traction and wide adoption. Many well-known businesses have begun accepting bitcoins as a means of making financial payments. However, the susceptibility of Bitcoin networks to information propagation delay, increases the vulnerability to attack of the Bitcoin network, and decreases its throughput performance. This paper introduces and critically analyses new network clustering methods, named Locality Based Clustering (LBC), Ping Time Based Approach (PTBC), Super Node Based Clustering …

Performance Modeling And Analysis Of A Thermoelectric Building Envelope For Space Heating, Xiaoli Liu, Ming Qu, Kazuaki Yazawa, Jorge Kohanoff, Piotr Chudzinski, Lorenzo Stella, Brian Norton, Niall Holmes Dr., Ruchita Jani, Hongxi Yin

Conference papers

To provide energy-efficient space heating and cooling, a thermoelectric building envelope (TBE) embeds thermoelectric devices in building walls. The thermoelectric device in the building envelope can provide active heating and cooling without requiring refrigerant use and energy transport among subsystems. Thus, the TBE system is energy and environmentally friendly. A few studies experimentally investigated the TBE under limited operating conditions, and only simplified models for the commercial thermoelectric module (TEM) were developed to quantify its performance. A holistic approach to optimum system performance is needed for the optimal system design and operation. The study developed a holistic TBE-building system model …

Event-Driven Servers Using Asynchronous, Non-Blocking Network I/O: Performance Evaluation Of Kqueue And Epoll, Lorcan Leonard

Dissertations

This research project evaluates the performance of kqueue and epoll in the context of event-driven servers. The evaluation is done through benchmarking and tracing which are used to measure throughput and execution time respectively. The experiment is repeated for both a virtualised and native server environment. The results from the experiment are statistically analysed and compared. These results show significant differences between kqueue and epoll, and a profound impact of virtualisation as a variable.

Cognitive Performance In Midlife Type 2 Diabetes: Results Form The Enbind Study, A. H. Dyer, L. Mckenna, G. Gamage, N. M. Bourke, Isabelle Killane, M. Widdowson, C. P. Woods, J. Gibney, R. Reilly, D. O'Neill, S. P. Kennelly

Articles

Aims: To establish the impact of uncomplicated type 2 diabetes on cognitive and neuropsychological performance in midlife. Methods: We performed a cross-sectional study of middle-aged adults with uncomplicated type 2 diabetes and a cohort of healthy control participants. General cognition was assessed using the Montreal Cognitive Assessment test and neuropsychological assessment was undertaken using a detailed neuropsychological assessment battery. Results: A total of 152 participants (102 with type 2 diabetes and 50 controls) were recruited (mean age 52 ± 8 years, 51% women). Participants with midlife type 2 diabetes were more than twice as likely to make an error on …

Adapting Microservices In The Cloud With Faas, Mateusz Pietraszewski

Dissertations

This project involves benchmarking, microservices and Function-as-a-service (FaaS) across the dimensions of performance and cost. In order to do a comparison this paper proposes a benchmark framework.

Performance Of Masonry Blocks Containing Different Proportions Of Incinator Bottom Ash, Niall Holmes, Hugh O'Malley, Paul Cribbin, Henry Mullen, Garrett Keane

Articles

No abstract provided.

Analysing The Impact Of Digital Photography Projects On Student Engagement And Performance In A Higher Education Engineering Discipline, Michael Gleeson

Conference papers

Developing and implementing engaging activities aligned with the learning outcomes of a module within a higher education programme is essential to successful teaching practice in the 21^st century. Substantial research evidence indicates that student engagement plays a pivotal role in the academic performance and success of the student. The aim of this research is to compare student performance after adopting an alternative pedagogic approach utilising digital photography as a tool to engage the student in an engineering discipline. The activity was designed to promote student engagement by integrating digital photography, replicating authentic construction professional practice and focusing on images …

A Study Of Integrated Uwb Antennas Optimised For Time Domain Performance, Antoine Dumoulin

Doctoral

Antennas for impulse radio ultra-wideband based portable devices are required to be compact and able to transmit or receive waveforms with minimal distortion in order to support proximity ranging with a centimetre-scale precision. The first part of thesis characterises several pulse types for use in the generation of picosecond-scale signals in respect to the regulatory power and frequency standards while the principles of antenna transient transmission and reception are stated. The proximity effect of planar conductors on the performance of an ultra-wideband antenna is investigated in both spectral and temporal domain demonstrating the relationship between the antenna-reflector separation and the …

Performance And Policy Evaluation Of Solar Energy Technologies For Domestic Application In Ireland, Lacour Ayompe

Doctoral

The aim of this research is to investigate the techno-economic and environmental performance of domestic scale grid-connected photovoltaic (PV) and forced circulation solar water heating (SWH) systems in Ireland; and propose a new feed-in tariff designed using a large sample of high resolution electricity demand data in order to provide credible information for informed policy formulation. Detailed field trials of experimental installations of a 1.72 kWp grid-connected PV and two SWH systems (with 4 m2 flat plate and 3 m2 heat pipe evacuated tube collectors) were undertaken to collect data. The energy, economic and environmental performances of the systems was …

Passive All-Fiber Wavelength Measurement Systems: Performance Determination Factors, Ginu Rajan, Yuliya Semenova, Agus Hatta, Gerald Farrell

Books/Book Chapters

No abstract provided.

Performance-Based Testing Methodology For Concrete Durability, Niall Holmes, P. A.Muhammed Basheer, Sreejith Nanukuttan, Lulu Basheer

Reports

This report presents an overview of performance based testing methodology for concrete durability and work currently underway jointly at Queens University Belfast and Heriot Watt University, Edinburgh, to undertake this research under a EPSRC funded project (EP/G02152X/1).

EN206-1 superseded BS 5328 on 1^st December 2003 and allows designers and producers to use a wide range of cements and aggregate types for a variety of exposure conditions. In this new standard, the durability of concrete is specified in terms of the constituent materials of concrete, properties of fresh and hardened concrete, limitations for concrete composition, specification of concrete, delivery of …

Conductivity Sensors To Monitor Cover-Zone Performance, W. J. Mccarter, T. M. Chrisp, G. Starrs, E. Owens, Niall Holmes, L. Basheer, S. V. Nanukuttan, M. Basheer

Conference papers

This paper presents developments in the use of an embedded, multi-electrode conductivity sensor to study the response of the concrete cover-zone to environmental action. The sensor enables an evaluation of the temporal and spatial variation of electrical conductivity thereby allowing an integrated assessment of the cover-zone. Conductivity sensors were embedded within concrete samples to study the cover-zone response to cyclic wetting and drying under laboratory conditions. This work was extended to include the use of remote interrogation methods to study samples placed at a marine exposure site and preliminary results are presented.

Investigation Of Dynamic And Steady State Calculation Methodologies For Determination Of Building Energy Performance In The Context Of The Epbd, Mervin Dean Doyle

Masters

The aim of this thesis was to investigate the ability of a dynamic and a quasi-steady state calculation methodology to capture the heating and cooling aspects of a buildings energy performance in the context of the requirements of the EU Energy Performance of Buildings Directive (EPBD). Chapters 1 and 2 provide a general background review and description of the implementation of the directive’s requirements in Ireland. Chapter 3 established the usefulness and relevance of building energy benchmarks, traditional approaches to building energy performance calculation methodologies. Chapter 4 established the ability of a sample of simplified and dynamic calculation tools to …

Effect Of Polarisation-Dependent Loss On The Performance Accuracy Of A Ratiometric Wavelength Measurement System, Ginu Rajan, Qian Wang, Yuliya Semenova, Gerald Farrell, Pengfei Wang

Articles

The polarisation-dependent loss (PDL) of a ratiometric wavelength measurement system and its influence on system's accuracy are investigated theoretically and experimentally. The PDL of a ratiometric system and the corresponding power ratio fluctuation is modelled, from which the accuracy of the measured wavelength can be estimated. An all-fibre wavelength measurement system is built to allow comparison of modelled and actual results. The measured ratio variation lies within the estimated limits. The measured wavelength error reaches about 1.41 plusmn 0.09 nm at 1550 nm in the demonstrated example (with an edge filter of average slope 0.22 dB/nm), which indicates the significant …

Performance Evaluation Of Video Streaming With Background Traffic Over Ieee 802.11 Wlan Networks, Nicola Cranley, Mark Davis

Conference papers

There is an increasing demand for multimedia streaming applications over WLAN networks. MPEG-4 and H.264 are compression standards targeted at high-quality streamed multimedia services over wireless best-effort IP networks. However, the dynamic nature of wireless networks in terms of fluctuating bandwidth and time-varying delays makes it difficult to provide good quality streaming under such constraints. Multimedia streaming applications are a demanding and challenging service to deliver over wireless networks. There is a trade-off between the capacity of the wireless network and the quality of the multimedia streaming application. In this paper we investigate the effect the background traffic load has …