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Full-Text Articles in Engineering

Dc Grid Power Congestion Management Laboratory Experiments, Holly Engelbrecht, Diego Zuidervliet, Peter Van Duijsen Oct 2023

Dc Grid Power Congestion Management Laboratory Experiments, Holly Engelbrecht, Diego Zuidervliet, Peter Van Duijsen

Research Papers

In the process of the electrical energy transition, a new curriculum for bachelor electrical engineering is developed. A new development is DC grids, as they are shown to be promising in solving the power congestion management problem. Particularly when adding solar power, battery storage, and load appliances including power electronics, DC grids are replacing AC grids, especially in micro-grids. The development of new laboratory experiments using three educational methods is described in this paper. First, theory combined with online calculation tools is used to prepare the students for the subject. Second, the experiment has to be prepared using simulation tools, …


Exploring The Potential For Scripting With Simulation In Engineering Education – Practical Examples Using Python And Ansys, Susannah Cooke, Susan Coleman, James Derrick Jan 2023

Exploring The Potential For Scripting With Simulation In Engineering Education – Practical Examples Using Python And Ansys, Susannah Cooke, Susan Coleman, James Derrick

Practice Papers

The ability to use scripting tools to harness the power of complex engineering software is not only critical for research and industry, but also offers opportunities for student learning and development. This paper covers two ways in which undergraduate engineering students have been exposed to Ansys simulation tools to be controlled from Python programs. A pilot series of ‘CodeFests’ have been held in partnership with university engineering departments, offering a fun way for students to engage with Python coding while exploring the power of scripting to optimise or iterate on solutions. These have used the PyMAPDL structural simulation library, leveraging …


3d Simulation Of A Yogurt Filling Machine Using Grafcet Studio And Factory Io: Realization Of Industry 4.0, Bashir Salah, Waqas Saleem, Razaullah Khan, Ahmed Tawhid Ahmed Soliman Jan 2023

3d Simulation Of A Yogurt Filling Machine Using Grafcet Studio And Factory Io: Realization Of Industry 4.0, Bashir Salah, Waqas Saleem, Razaullah Khan, Ahmed Tawhid Ahmed Soliman

Articles

Manufacturing systems, enterprises and academic institutions worldwide are implementing industry 4.0 (IR4.0). By integrating the services and equipment, IR4.0 develops autonomous systems that manage industrial operations and exchange real-time data in real time. This study includes a simulation of an existing production system using the GRAFCET Studio software.


Assessing The Impact Of Contact Tracing With An Agent-Based Model For Simulating The Spread Of Covid-19: The Irish Experience, Elizabeth Hunter, Sudipta Saha, Jwenish Kumawat, Ciara Carroll, John Kelleher, Claire Buckley, Conor Mcaloon, Patricia Kearney, Michelle Gilbert, Greg Martin Jan 2023

Assessing The Impact Of Contact Tracing With An Agent-Based Model For Simulating The Spread Of Covid-19: The Irish Experience, Elizabeth Hunter, Sudipta Saha, Jwenish Kumawat, Ciara Carroll, John Kelleher, Claire Buckley, Conor Mcaloon, Patricia Kearney, Michelle Gilbert, Greg Martin

Articles

Contact tracing is an important tool in managing infectious disease outbreaks and Ireland used a comprehensive contact tracing program to slow the spread of COVID-19. Although the benefits of contact tracing seem obvious, it is difficult to estimate the actual impact contact tracing has on an outbreak because it is hard to separate the effects of contact tracing from other behavioural changes or interventions. To understand the impact contact tracing had in Ireland, we used an agent-based model that is designed to simulate the spread of COVID-19 through Ireland. The model uses real contact tracing data from the first year …


Reality Analagous Synthetic Dataset Generation With Daylight Variance For Deep Learning Classification, Thomas Lee, Susan Mckeever, Jane Courtney Aug 2022

Reality Analagous Synthetic Dataset Generation With Daylight Variance For Deep Learning Classification, Thomas Lee, Susan Mckeever, Jane Courtney

Conference papers

For the implementation of Autonomously navigating Unmanned Air Vehicles (UAV) in the real world, it must be shown that safe navigation is possible in all real world scenarios. In the case of UAVs powered by Deep Learning algorithms, this is a difficult task to achieve, as the weak point of any trained network is the reduction in predictive capacity when presented with unfamiliar input data. It is possible to train for more use cases, however more data is required for this, requiring time and manpower to acquire. In this work, a potential solution to the manpower issues of exponentially scaling …


Validating And Testing An Agent-Based Model For The Spread Of Covid-19 In Ireland, Elizabeth Hunter, John D. Kelleher Aug 2022

Validating And Testing An Agent-Based Model For The Spread Of Covid-19 In Ireland, Elizabeth Hunter, John D. Kelleher

Articles

Agent-based models can be used to better understand the impacts of lifting restrictions or implementing interventions during a pandemic. However, agent-based models are computationally expensive, and running a model of a large population can result in a simulation taking too long to run for the model to be a useful analysis tool during a public health crisis. To reduce computing time and power while running a detailed agent-based model for the spread of COVID-19 in the Republic of Ireland, we introduce a scaling factor that equates 1 agent to 100 people in the population. We present the results from model …


Generating Reality-Analogous Datasets For Autonomous Uav Navigation Using Digital Twin Areas, Thomas Lee, Susan Mckeever, Jane Courtney Jun 2022

Generating Reality-Analogous Datasets For Autonomous Uav Navigation Using Digital Twin Areas, Thomas Lee, Susan Mckeever, Jane Courtney

Conference papers

In order for autonomously navigating Unmanned Air Vehicles(UAVs) to be implemented in day-to-day life, proof of safe operation will be necessary for all realistic navigation scenarios. For Deep Learning powered navigation protocols, this requirement is challenging to fulfil as the performance of a network is impacted by how much the test case deviates from data that the network was trained on. Though networks can generalise to manage multiple scenarios in the same task, they require additional data representing those cases which can be costly to gather. In this work, a solution to this data acquisition problem is suggested by way …


Aspen Plus Simulation Of Biomass Gasification In A Steam Blown Dual Fluidised Bed, Wayne Doherty, Anthony Reynolds, David Kennedy Aug 2013

Aspen Plus Simulation Of Biomass Gasification In A Steam Blown Dual Fluidised Bed, Wayne Doherty, Anthony Reynolds, David Kennedy

Book/Book Chapters

The efficient utilisation of biomass resources is of utmost importance. Biomass gasification offers much higher efficiencies than combustion. Gasification is a process in which a fuel is converted to a combustible gas (syngas). A dual fluidised bed gasifier known as the fast internally circulating fluidised bed (FICFB) was selected. It has been demonstrated at industrial scale and data is readily available for model validation. An Aspen Plus model was developed to simulate the FICFB gasifier. The model is based on Gibbs free energy minimisation and the restricted equilibrium method was used to calibrate it. The model has been validated and …


Microsimulation Evaluation Of Eurocode Load Model For American Long-Span Bridges, Bernard Enright, Colm Carey, Colin Caprani Jan 2013

Microsimulation Evaluation Of Eurocode Load Model For American Long-Span Bridges, Bernard Enright, Colm Carey, Colin Caprani

Articles

The ability to accurately predict traffic loading is essential for cost-effective bridge maintenance and repair programs. The traffic load model currently used in the United States for the design of long-span bridges was developed over three decades ago. In the meantime vehicle characteristics and traffic patterns have changed. The Eurocode for traffic loading is more recent, but was calibrated only for bridges up to 200 m long. In this work, Weigh-In-Motion traffic records from 11 different sites across Alabama are used to establish congested traffic loading. Traffic microsimulation is used to generate the congestion, based on the real traffic data. …


A Simulation-Based Decision Support System To Model Complex Demand Driven Heathcare Facilities, Amr Arisha, Michael Thorwarth Dec 2012

A Simulation-Based Decision Support System To Model Complex Demand Driven Heathcare Facilities, Amr Arisha, Michael Thorwarth

Conference papers

Simulating healthcare processes is a sophisticated endeavor. Treatment processes and patient arrival patterns differ significantly in their statistical attributes and implicate a high degree of variability. In addition, there are several types of interconnected processes of medical staff involved that accompany a patient’s journey through the healthcare facility. Replicating this behavior with process flow models in a discrete event simulation model is highly complex and therefore difficult to create while maintaining a high degree of precision. A framework is thus introduced which delivers an algorithm that allows to implement Multiple Participant Pathway Modeling (MPPM) under the consideration of Flexible Resource …


Capacity Planning For Elderly Care In Ireland Using Simluation Modeling, Mohamed Ragab, Waleed Abo Hamad, Amr Arisha Nov 2012

Capacity Planning For Elderly Care In Ireland Using Simluation Modeling, Mohamed Ragab, Waleed Abo Hamad, Amr Arisha

Conference papers

Global population aging is creating an immense pressure on healthcare facilities making them unable to cope with the growing demand for elderly healthcare services. Current demand-supply gaps result in prolonged waiting times for patients and substantial cost burdens for healthcare systems due to delayed discharges. This paper describes a project aimed at presenting modeling and simulation to address elderly care pathways within the Irish healthcare sector. The management of frail patients admitted to acute hospitals and the introduction of the new intermediate care beds are alternative interventions that healthcare executives are interested in simulating to examine their impact on the …


The Implementation Of A Visco-Hyperelastic Numerical Material Model For Simulating The Behaviour Of Polymer Foam Materials, Conor Briody, Barry Duignan, Stephen Jerrams, John Tiernan Apr 2012

The Implementation Of A Visco-Hyperelastic Numerical Material Model For Simulating The Behaviour Of Polymer Foam Materials, Conor Briody, Barry Duignan, Stephen Jerrams, John Tiernan

Articles

Polyurethane foam has been in use for some time in wheelchair seating systems as it offers good pressure relieving capabilities in most cases. However, little characterisation work has gone into seating foam materials by comparison with conventional elastomeric materials. Accurate material models could allow better prediction of foam in-service behaviour, which could potentially improve seating design practises. The objective of this work was to develop an approach for the validation of hyperelastic and viscoelastic material model parameters used to simulate polyurethane foam behaviour. Material parameters were identified from relevant test procedures and implemented in a Finite Element simulation of an …


A Simulation Analysis Of Photovoltaic Ac Module Integrated Converters In Parallel, Under Controlled Edge Shading Conditions, Lynette O'Callaghan, Mick Mckeever, Brian Norton Jan 2012

A Simulation Analysis Of Photovoltaic Ac Module Integrated Converters In Parallel, Under Controlled Edge Shading Conditions, Lynette O'Callaghan, Mick Mckeever, Brian Norton

Conference Papers

A DC and AC power simulation comparison of: a Photovoltaic (PV) array with a modular, parallel, AC converter configuration; and a series, string configuration with a central AC converter, is presented. The systems are simulated using a comprehensive range of edge shading scenarios and irradiance conditions. Power control and transformation circuitry must be designed for shade and module mismatch tolerance to prevent over-proportional power to shade losses, as average losses from Building Integrated PV (BIPV) systems are approximately 20 to 25%, due to shade, mismatch, differences in orientation and inclination, and temperature effects. 59.4% of the simulations showed gains in …


Simulation-Based Optimisation Model For The Lean Assessment In Sme: A Case Study, Amr Arisha, Amr Mahfouz, John Shea Dec 2011

Simulation-Based Optimisation Model For The Lean Assessment In Sme: A Case Study, Amr Arisha, Amr Mahfouz, John Shea

Conference papers

Due to their space limitation and small production scale, small and medium enterprises (SME) are vulner-able to rapid changes. Lean principles are considered as effective improvement approach to eliminate sys-tem’s waste and inefficiencies. Although much of the academic materials have addressed the lean practic-es into large, global companies, they can still be adjusted to SMEs. Risks are usually associated with lean implementation process due to the drastic required changes in business policies and operations. Simulation can be successfully used to predict the impact of the proposed changes ahead of the implementation which helps to mitigate risks. Integrating simulation with optimization …


Some Experiences, Thoughts, Ideas And Open Questions Relating To Applied Thermodynamics, Jim Mcgovern Apr 2011

Some Experiences, Thoughts, Ideas And Open Questions Relating To Applied Thermodynamics, Jim Mcgovern

Articles

In this paper I present some of my thoughts and experiences relating to 'applied thermodynamics' over my career so far. I explain my interest in thermodynamics, describe some topics I have worked on, point out some questions that appear still to be open and outline some ideas for work that could be done. I describe how I was inspired to pursue the area of applied thermodynamics, with reference to a glass, opposed-piston internal combustion engine. I put my heat pump research in the late 1970s briefly into today's context. Some of my research has been in relation to compressors, which …


Customer Management Analysis Of Irish Plumbing & Heating Distribution System: A Simulation Study, Amr Arisha, Amr Mahfouz, John Crowe, Finbarr Bennett Aug 2010

Customer Management Analysis Of Irish Plumbing & Heating Distribution System: A Simulation Study, Amr Arisha, Amr Mahfouz, John Crowe, Finbarr Bennett

Conference papers

The sudden burst of the property bubble, coupled with current global economic conditions has resulted in a huge decrease in demand for plumbing and heating fixtures in the Irish construction industry. Moreover, inefficient supply chain management policies have imposed further pressures on companies resulting in more system bottlenecks and unnecessary costs. Inventory management is seen as a functional area that can ease such bottlenecks and in turn increase supply chain efficiency, decrease costs and increase customer satisfaction. The challenge is to predict the balance of on-hand inventory and order quantity to optimise customer satisfaction and minimise inventory cost. It is …


Simulation Of A Tubular Solid Oxide Fuel Cell Stack Operating On Biomass Syngas Using Aspen Plus, Wayne Doherty, Anthony Reynolds, David Kennedy May 2010

Simulation Of A Tubular Solid Oxide Fuel Cell Stack Operating On Biomass Syngas Using Aspen Plus, Wayne Doherty, Anthony Reynolds, David Kennedy

Articles

A tubular solid oxide fuel cell (SOFC) stack was modelled and its operation on biomass syn-gas was investigated. The objective of this work was to develop a computer simulation model of a biomass gasification-SOFC (BG-SOFC) system capable of predicting performance under various operating conditions and using diverse fuels. The stack was modelled using Aspen Plus and considers ohmic, activation and concentration losses. It was validated against published data for operation on natural gas. Operating parameters such as fuel and air utilisation factor Uf and Ua, current density j and steam to carbon ratio STCR were varied and …


Validation Of A Simulation Model For A Combined Otto And Stirling Cycle Power Plant, Jim Mcgovern, Barry Cullen, Michel Feidt, Stoian Petrescu May 2010

Validation Of A Simulation Model For A Combined Otto And Stirling Cycle Power Plant, Jim Mcgovern, Barry Cullen, Michel Feidt, Stoian Petrescu

Conference Papers

A project has been underway at the Technological University Dublin (DIT) to investigate the feasibility of a combined Otto and Stirling cycle power plant in which a Stirling cycle engine would serve as a bottoming cycle for a stationary Otto cycle engine. This type of combined cycle plant is considered to have good potential for industrial use. This paper describes work by DIT and collaborators to validate a computer simulation model of the combined cycle plant. In investigating the feasibility of the type of combined cycle that is proposed there are a range of practical realities to be faced and …


Simulation Of Traffic Loading On Highway Bridges, Bernard Enright Mar 2010

Simulation Of Traffic Loading On Highway Bridges, Bernard Enright

Other resources

This work is based on weigh-in-motion measurements for approximately three million trucks obtained from sites in five European countries. Techniques have been developed, supported by photographic evidence, for filtering the measurements to identify and remove unreliable values, and for the classification of extremely heavy vehicles. The collected measurements have been used as the basis for building and calibrating a Monte Carlo simulation model for bridge loading. Two-lane traffic is simulated – either two lanes in the same direction or one lane in each direction. The model allows for vehicles that are both heavier and have more axles than in the …


Practical Simulation Application: Evaluation Of Process Control Parameters In Twisted-Pair Cables Manufacturing System, Amr Mahfouz, Said Hassan, Amr Arisha Jan 2010

Practical Simulation Application: Evaluation Of Process Control Parameters In Twisted-Pair Cables Manufacturing System, Amr Mahfouz, Said Hassan, Amr Arisha

Articles

Intensive competition and rapid technology development of Twisted-Pair Cables (TPC) industry have left no room for competing manufacturers to harbour system inefficiencies. TPC are used in various communication and networks hardware applications; their manufacturing facilities face many challenges including various product configurations with different equipment settings, different product flows and Work in Process (WIP) space limitations. The quest for internal efficiency and external effectiveness forces companies to align their internal settings and resources with external requirements/orders, or in different words, significant factors must be set appropriately and identified prior to manufacturing processes. Integrated definition models (IDEF0, IDEF3) in conjunction with …


Site Specific Modelling Of Traffic Loading On Highway Bridges, Bernard Enright, Eugene J. Obrien Jan 2010

Site Specific Modelling Of Traffic Loading On Highway Bridges, Bernard Enright, Eugene J. Obrien

Conference papers

Accurate traffic loading models based on measured weigh-in-motion (WIM) data are essential for the accurate assessment of existing bridges. Much work has been published on the Monte Carlo simulation of single lanes of heavy vehicle traffic, and this can easily be extended to model the loading on bridges with two streams of traffic in opposing directions. However, a typical highway bridge will have multiple lanes in the same direction, and various types of correlation are evident in measured traffic, such as groups of very heavy vehicles travelling together and heavy vehicles being overtaken by lighter ones. These traffic patterns affect …


The Influence Of Correlation On The Extreme Traffic Loading Of Bridges, Eugene J. Obrien, Bernard Enright, A. T. Dempsey Jan 2010

The Influence Of Correlation On The Extreme Traffic Loading Of Bridges, Eugene J. Obrien, Bernard Enright, A. T. Dempsey

Conference papers

Accurate traffic loading models based on measured data are essential for the accurate assessment of existing bridges. There are well-established methods for the Monte Carlo simulation of single lanes of traffic, and this can easily be extended to model the loading on bridges with two independent streams of traffic in opposing directions. However, a typical highway bridge will have multiple lanes in the same direction, and various types of correlation are evident in measured traffic. This paper analyses traffic patterns using multi-lane WIM data collected at two European sites. It describes an approach to the Monte Carlo simulation of this …


Importance Of The Tail In Truck Weight Modeling For Bridge Assessment, Eugene J. Obrien, Bernard Enright, Abraham Getachew Jan 2010

Importance Of The Tail In Truck Weight Modeling For Bridge Assessment, Eugene J. Obrien, Bernard Enright, Abraham Getachew

Articles

To predict characteristic extreme traffic load effects, simulations are sometimes performed of bridge loading events. To generalize the truck weight data, statistical distributions are fitted to histograms of weight measurements. This paper is based on extensive WIM measurements from two European sites and shows the sensitivity of the characteristic traffic load effects to the fitting process. A semi-parametric fitting procedure is proposed: direct use of the measured histogram where there are sufficient data for this to be reliable and parametric fitting to a statistical distribution in the tail region where there are less data. Calculated characteristic load effects are shown …


Simulation Model To Investigate Flexible Workload Management For Healthcare And Servicescape Environment, Michael Thorwarth, Paul Harper, Amr Arisha Dec 2009

Simulation Model To Investigate Flexible Workload Management For Healthcare And Servicescape Environment, Michael Thorwarth, Paul Harper, Amr Arisha

Conference papers

High demand and poor staffing conditions cause avoidable pressure and stress among healthcare personnel which results in burnout symptoms and unplanned absenteeism which are hidden cost drivers. The work environment within an emergency department is commonly arranged in a flexible workload which is highly dynamic and complex for the outside observer. Using detailed simulation modeling within structured modeling methods, a comprehensive model to characterize the nurses' time utilization in such flexible dynamic workload environment was investigated. The results have been used to derive a generalized analytic expression that describes certain settings that lead to an instable queuing system with serious …


Preliminary Modelling Results For An Otto Cycle/Stirling Cycle Hybrid-Engine-Based Power Generation System, Barry Cullen, Jim Mcgovern, Michel Feidt, Stoian Petrescu Aug 2009

Preliminary Modelling Results For An Otto Cycle/Stirling Cycle Hybrid-Engine-Based Power Generation System, Barry Cullen, Jim Mcgovern, Michel Feidt, Stoian Petrescu

Conference Papers

This paper presents preliminary data and results for a system mathematical model for a proposed Otto Cycle / Stirling Cycle hybrid-engine-based power generation system. The system is a combined cycle system with the Stirling cycle machine operating as a bottoming cycle on the Otto cycle exhaust. The application considered is that of a stationary power generation scenario wherein the Stirling cycle engine operates as a waste heat recovery device on the exhaust stream of the Otto cycle engine. This paper is primarily concerned with the development of a model for a suitable Stirling cycle engine capable of running on the …


Highway Bridge Assessment For Dynamic Interaction With Critical Vehicles, Daniel Cantero, Eugene J. Obrien, Arturo González, Bernard Enright, Cillian Rowley Jan 2009

Highway Bridge Assessment For Dynamic Interaction With Critical Vehicles, Daniel Cantero, Eugene J. Obrien, Arturo González, Bernard Enright, Cillian Rowley

Conference papers

Dynamic vehicle-bridge interaction is often considered for the most common classes of vehicle such as the 5-axle articulated truck. However, the dynamic response of bridges to this type of trucks is quite different to the response to the vehicles more likely to feature in maximum-in-lifetime traffic loading events. This paper focuses on large (>100 tonne) cranes and crane-type vehicles that have been recorded at Weigh-in-Motion sites in Europe. This paper analyses the total bending moment due to these vehicles on short to medium span bridges and compare them to 5- axle articulated trucks. To account for the variability in …


Simulation Of A Tubular Solid Oxide Fuel Cell Stack Operating On Biomass Syn-Gas Using Aspen Plus, Wayne Doherty, Anthony Reynolds, David Kennedy Jan 2009

Simulation Of A Tubular Solid Oxide Fuel Cell Stack Operating On Biomass Syn-Gas Using Aspen Plus, Wayne Doherty, Anthony Reynolds, David Kennedy

Articles

A tubular solid oxide fuel cell (SOFC) stack is modelled and its operation on biomass syn-gas is investigated. The objective of this work is to develop a computer simulation model of a biomass gasification-SOFC (BG-SOFC) system capable of predicting performance under various operating conditions and using diverse fuels. The stack is modelled using Aspen Plus and considers ohmic, activation and concentration losses. It is validated against published data for operation on natural gas. Operating parameters such as fuel and air utilisation factor (Uf and Ua), current density (j) and steam to carbon ratio ( …


An Engineering Evaluation Of Ankle Prosthetics, Christopher Thian, Stephen Tiernan, Fiona Mcevoy, Robert Flavin Sep 2008

An Engineering Evaluation Of Ankle Prosthetics, Christopher Thian, Stephen Tiernan, Fiona Mcevoy, Robert Flavin

Conference Papers

There are a wide range of different types of ankle replacements on the market today each with a
different mechanical design. Unfortunately the results of ankle replacements are not as good as hip
and knee replacements; this is due to the complexity of the ankle joint. In the early days of ankle
replacements some of the prosthetics only lasted 4 months. Recent developments have improved the
longevity of the replacements although, there are still many complications and failures of the
replacements, these include; the prosthetic components migrating into the bone, the components
failing due to stresses induced by the forces …


Simulation Of A Circulating Fluidised Bed Biomass Gasifier Using Aspen Plus: A Performance Analysis, Wayne Doherty, Anthony Reynolds, David Kennedy Jan 2008

Simulation Of A Circulating Fluidised Bed Biomass Gasifier Using Aspen Plus: A Performance Analysis, Wayne Doherty, Anthony Reynolds, David Kennedy

Conference Papers

In the near future biomass gasification is likely to play an important role in energy production and conversion. Its application has great potential in the context of climate change mitigation, increasing efficiency and energy security. Atmospheric circulating fluidised bed (CFB) technology was selected for the current study. An original computer simulation model of a CFB biomass gasifier was developed using ASPEN Plus (Advanced System for Process ENgineering Plus). It is based on Gibbs free energy minimisation and the restricted equilibrium method was used to calibrate it against experimental data. This was achieved by specifying the temperature approach for the gasification …


Process Modelling Support For The Conceptual Modelling Phase Of A Simulation Project, Cathal Heavey, John Ryan Dec 2006

Process Modelling Support For The Conceptual Modelling Phase Of A Simulation Project, Cathal Heavey, John Ryan

Conference papers

While many developments have taken place around supporting the model coding task of simulation, there are few tools available to assist in the conceptual modelling phase. Several authors have reported the advantages of using process modelling tools in the early phases of a simulation project.

This paper provides an overview of process modelling tools in relation to their support for simulation, categorizing the tools into formal method and descriptive methods. A conclusion from this review is that none of the tools available adequately support the requirements gathering phase of simulation. This is not surprising as none of the process modelling …