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Full-Text Articles in Science and Technology Studies
Impact Of Wind Generator Control Strategies On Flicker Emission In Distribution Networks, Lasantha Meegahapola, Sarath Perera
Impact Of Wind Generator Control Strategies On Flicker Emission In Distribution Networks, Lasantha Meegahapola, Sarath Perera
Dr Lasantha G Meegahapola
Renewable power generators are increasingly being integrated to electricity networks to achieve future renewable energy targets in power generation. In particular, wind power generation has already reported substantial penetration levels in electricity networks. Traditionally, flicker phenomenon is considered to be one of the power quality issues in power distribution networks due to fluctuating consumer loads connected to the network. Large-scale integration of wind power generators may create significant voltage fluctuations in distribution feeders due to stochastic and intermittent nature of the wind resources. This study aims to investigate and characterize the flicker emission under different control strategies for DFIG based …
Impact Of Wind Generation Mix On Transient Stability For An Interconnected Power System, Lasantha Meegahapola, Damian Flynn, Jason Kennedy, Tim Littler
Impact Of Wind Generation Mix On Transient Stability For An Interconnected Power System, Lasantha Meegahapola, Damian Flynn, Jason Kennedy, Tim Littler
Dr Lasantha G Meegahapola
The rapid growth of wind generation in many European countries is pushing power systems into uncharted territory. As additional wind generators are installed, the changing generation mix may impact on power system stability. This paper adopts the New England 39 bus system as a test system for transient stability analysis. Thermal generator models are based on a likely future plant mix for existing systems, while varying capacities of fixed-speed induction generators (FSIG) and doubly-fed induction generators (DFIG) are considered. The main emphasis here has been placed on the impact of wind technology mix on inter-area oscillations following transient grid disturbances. …
Impact On Transient And Frequency Stability For A Power System At Very High Wind Penetration, Lasantha Meegahapola, Damian Flynn
Impact On Transient And Frequency Stability For A Power System At Very High Wind Penetration, Lasantha Meegahapola, Damian Flynn
Dr Lasantha G Meegahapola
This paper analyzes the impact on transient and frequency stability for a power system at very high wind penetration (40% wind). Wind penetration is based on the doubly-fed induction generator (DFIG), and a systematic approach has been adopted for wind power integration. A sensitivity analysis has been carried out for each wind integration scenario and for different wind generator loading conditions. A range of fault locations has been selected for stability analysis based on the proximity to synchronous generation and wind farms. The analysis has shown that transient stability performance is subject to fault location in the network, especially when …
Impact Of Chemical Cleaning On The Nanofiltration Of Pharmaceutically Active Compounds (Phacs): The Role Of Cleaning Temperature, Alexander Simon, William E. Price, Long D. Nghiem
Impact Of Chemical Cleaning On The Nanofiltration Of Pharmaceutically Active Compounds (Phacs): The Role Of Cleaning Temperature, Alexander Simon, William E. Price, Long D. Nghiem
William E. Price
This study investigated the impact of chemical cleaning on the physicochemical properties of a nanofiltration membrane and its subsequent separation efficiency of inorganic salts and two pharmaceutically active compounds (PhACs), sulfamethoxazole and carbamazepine. Chemical cleaning was simulated by immersing virgin membrane samples in aqueous citric acid, sodium hydroxide (NaOH), ethylenediaminetetraacetic-acid (EDTA) and sodium dodecyl sulphate (SDS) at various temperatures for 18 h. The cleaning temperature did not exert any discernible impact on the surface charge of the NF270 membrane selected in this study. However, high cleaning temperatures were shown to either amplify or reduce the impact of chemical cleaning on …
Dynamic Testing Of Tekseal High Yield Grout To Provide An Orepass Plug Designed For Impact, I V. S Mutton, Alexander Remennikov, D Pateman
Dynamic Testing Of Tekseal High Yield Grout To Provide An Orepass Plug Designed For Impact, I V. S Mutton, Alexander Remennikov, D Pateman
Alex Remennikov
Significant wear in orepasses particularly in the brow and chute areas is proportional to the tonnage throughput with increased wear associated with running orepasses empty. During planned shutdowns it may be necessary to isolate maintenance crews from objects falling from orepasses. In the last 15 years grout orepass plugs that can later be easily removed have been poured above chute maintenance areas. These provide protection from high energy impact and isolating workers from the hazard. Construction and removal methods will be briefly explained. Since it is not feasible to investigate the problem of orepass plug impact response using full-scale experimental …
The Response Of Axially Restrained Non-Composite Steel-Concrete-Steel Sandwich Panels Due To Large Impact Loading, Alex M. Remennikov, Sih Ying Kong, Brian Uy
The Response Of Axially Restrained Non-Composite Steel-Concrete-Steel Sandwich Panels Due To Large Impact Loading, Alex M. Remennikov, Sih Ying Kong, Brian Uy
Alex Remennikov
In conventional steel-concrete-steel (SCS) construction, the external steel plates are connected to the concrete infill by welded shear stud connectors. This paper describes a programme of experimental and numerical investigations on reduced-scale non-composite SCS panels with axially restrained connections. The experimental results have demonstrated that the non-composite SCS panels are capable of developing enhanced load-carrying capacity through the tensile membrane resistance of the steel faceplates. This type of construction was found to exhibit highly ductile response and be able to sustain large end rotations of up to 18° without collapse. High fidelity finite element models for SCS panels under impact …
Studying The Impact Of The Corner Propagation Model On Vanet Routing In Urban Environments, Abhinay Mukunthan, Craig Cooper, Farzad Safaei, D. Franklin, Mehran Abolhasan
Studying The Impact Of The Corner Propagation Model On Vanet Routing In Urban Environments, Abhinay Mukunthan, Craig Cooper, Farzad Safaei, D. Franklin, Mehran Abolhasan
Professor Farzad Safaei
Accurate modelling of the radio channel is often the most difficult aspect of a Vehicular Ad Hoc Network (VANET) simulation due to the large variability present in vehicular terrain. CORNER is a propagation model that calculates path-loss in an urban terrain with a large concentration of buildings, based on the position of the transmitter and receiver on a street map. This paper proposes additions to the CORNER propagation model to take selective multi-path fading into account and investigates the performance of the GPSR routing protocol under the CORNER propagation model in a realistic city environment.
The Impact Of Different Rotation Patterns On The Sampling Variance Of Seasonally Adjusted And Trend Estimates, Craig Mclaren, David Steel
The Impact Of Different Rotation Patterns On The Sampling Variance Of Seasonally Adjusted And Trend Estimates, Craig Mclaren, David Steel
Professor David Steel
Many economic and social time series are based on sample surveys which have complex sample designs. The sample design affects the properties of the time series. In particular, the overlap of the sample from period to period affects the variability of the time series of survey estimates, and the seasonally adjusted and trend estimates produced from them. The Census X11 and X11ARIMA packages are commonly used to produce seasonally adjusted estimates and can also be used to produce estimates of trend. This paper considers the implications of different overlap patterns on the sampling variance of seasonally adjusted and trend estimates …
Impact Of Mains Connected Three-Phase Induction Motor Loading Levels On Network Voltage Unbalance Attenuation, Upuli Jayatunga, Sarath Perera, Philip Ciufo
Impact Of Mains Connected Three-Phase Induction Motor Loading Levels On Network Voltage Unbalance Attenuation, Upuli Jayatunga, Sarath Perera, Philip Ciufo
Dr Philip Ciufo
Voltage unbalance (VU) in power systems should be managed in a systematic manner in order to minimise its adverse effects on both customer equipment and supply utilities. It is a well known fact that three-phase induction motor performance can be significantly affected in the presence of supply voltage unbalance. It is also known that three-phase induction motors can help to reduce pre-existing network voltage unbalance levels. Recently undertaken research aligned with IEC/TR 61000-3-13:2008 Technical Report on voltage unbalance management (emission allocation and emission assessment) have quantified the contribution made by induction motors to the net voltage unbalance at a point …
A Model Of The Effects Of Authority On Consensus Formation In Adaptive Networks: Impact On Network Topology And Robustness, Brenton J. Prettejohn, Matthew J. Berryman, Mark D. Mcdonnell
A Model Of The Effects Of Authority On Consensus Formation In Adaptive Networks: Impact On Network Topology And Robustness, Brenton J. Prettejohn, Matthew J. Berryman, Mark D. Mcdonnell
Faculty of Engineering and Information Sciences - Papers: Part A
Opinions of individuals in real social networks are arguably strongly influenced by external determinants, such as the opinions of those perceived to have the highest levels of authority. In order to model this, we have extended an existing model of consensus formation in an adaptive network by the introduction of a parameter representing each agent's level of 'authority' based on their opinion relative to the overall opinion distribution. We found that introducing this model, along with a randomly varying opinion convergence factor, significantly impacts the final state of converged opinions and the number of interactions required to reach that state. …
The Response Of Axially Restrained Non-Composite Steel-Concrete-Steel Sandwich Panels Due To Large Impact Loading, Alex M. Remennikov, Sih Ying Kong, Brian Uy
The Response Of Axially Restrained Non-Composite Steel-Concrete-Steel Sandwich Panels Due To Large Impact Loading, Alex M. Remennikov, Sih Ying Kong, Brian Uy
Faculty of Engineering and Information Sciences - Papers: Part A
In conventional steel-concrete-steel (SCS) construction, the external steel plates are connected to the concrete infill by welded shear stud connectors. This paper describes a programme of experimental and numerical investigations on reduced-scale non-composite SCS panels with axially restrained connections. The experimental results have demonstrated that the non-composite SCS panels are capable of developing enhanced load-carrying capacity through the tensile membrane resistance of the steel faceplates. This type of construction was found to exhibit highly ductile response and be able to sustain large end rotations of up to 18° without collapse. High fidelity finite element models for SCS panels under impact …
Dynamic Testing Of Tekseal High Yield Grout To Provide An Orepass Plug Designed For Impact, I V. S Mutton, Alexander Remennikov, D Pateman
Dynamic Testing Of Tekseal High Yield Grout To Provide An Orepass Plug Designed For Impact, I V. S Mutton, Alexander Remennikov, D Pateman
Faculty of Engineering and Information Sciences - Papers: Part A
Significant wear in orepasses particularly in the brow and chute areas is proportional to the tonnage throughput with increased wear associated with running orepasses empty. During planned shutdowns it may be necessary to isolate maintenance crews from objects falling from orepasses. In the last 15 years grout orepass plugs that can later be easily removed have been poured above chute maintenance areas. These provide protection from high energy impact and isolating workers from the hazard. Construction and removal methods will be briefly explained. Since it is not feasible to investigate the problem of orepass plug impact response using full-scale experimental …
Impact Of Chemical Cleaning On The Nanofiltration Of Pharmaceutically Active Compounds (Phacs): The Role Of Cleaning Temperature, Alexander Simon, William E. Price, Long D. Nghiem
Impact Of Chemical Cleaning On The Nanofiltration Of Pharmaceutically Active Compounds (Phacs): The Role Of Cleaning Temperature, Alexander Simon, William E. Price, Long D. Nghiem
Faculty of Engineering and Information Sciences - Papers: Part A
This study investigated the impact of chemical cleaning on the physicochemical properties of a nanofiltration membrane and its subsequent separation efficiency of inorganic salts and two pharmaceutically active compounds (PhACs), sulfamethoxazole and carbamazepine. Chemical cleaning was simulated by immersing virgin membrane samples in aqueous citric acid, sodium hydroxide (NaOH), ethylenediaminetetraacetic-acid (EDTA) and sodium dodecyl sulphate (SDS) at various temperatures for 18 h. The cleaning temperature did not exert any discernible impact on the surface charge of the NF270 membrane selected in this study. However, high cleaning temperatures were shown to either amplify or reduce the impact of chemical cleaning on …
Impact Of Patient Rotational Errors On Target And Critical Structure Dose In Imrt: A 3d Simulation Study, S Arumugam, A Xing, P Vial, A Scotti, R Stirton, G Goozee, Lois Holloway
Impact Of Patient Rotational Errors On Target And Critical Structure Dose In Imrt: A 3d Simulation Study, S Arumugam, A Xing, P Vial, A Scotti, R Stirton, G Goozee, Lois Holloway
Faculty of Engineering and Information Sciences - Papers: Part A
The impact of 3D rotational errors in patient positioning on dose delivered target volumes and critical structures in IMRT was studied. Patient rotational errors ranging from -30 to +30 was introduced to IMRT treatment plans of pelvis, head and neck and brain treatment sites and the impact of rotational error on DVH metrics was assessed. The magnitude of impact of rotational error on the error in dose delivered to the target volume and critical structures depends on the location of the structures from plan isocentre. In studied plans, a maximum percentage difference of up to -9.8(1s=13.4) % in D95 to …
Enhancing Impact Fracture Toughness And Tensile Properties Of A Microalloyed Cast Steel By Hot Forging And Post-Forging Heat Treatment Processes, Jingwei Zhao, Zhengyi Jiang, Chong Soo Lee
Enhancing Impact Fracture Toughness And Tensile Properties Of A Microalloyed Cast Steel By Hot Forging And Post-Forging Heat Treatment Processes, Jingwei Zhao, Zhengyi Jiang, Chong Soo Lee
Faculty of Engineering and Information Sciences - Papers: Part A
In the present work, the effects of hot forging and post-forging heat treatment on the impact fracture toughness and tensile properties of a microalloyed cast steel were investigated. Mechanical tests were used to evaluate the room temperature impact fracture toughness and tensile properties of the steel. The resulting microstructures were analysed by optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The extraction replica technology was used to investigate the characterisation of complex precipitates formed during heat treatment. The obtained results showed that the coarse-grained microstructure of the forged specimen was significantly refined after post-forging heat treatment. …
Impact Of Humic Acid Fouling On Membrane Performance And Transport Of Pharmaceutically Active Compounds In Forward Osmosis, Ming Xie, Long D. Nghiem, William E. Price, Menachem Elimelech
Impact Of Humic Acid Fouling On Membrane Performance And Transport Of Pharmaceutically Active Compounds In Forward Osmosis, Ming Xie, Long D. Nghiem, William E. Price, Menachem Elimelech
Faculty of Engineering and Information Sciences - Papers: Part A
The impact of humic acid fouling on the membrane transport of two pharmaceutically active compounds (PhACs) - namely carbamazepine and sulfamethoxazole - in forward osmosis (FO) was investigated. Deposition of humic acid onto the membrane surface was promoted by the complexation with calcium ions in the feed solution and the increase in ionic strength at the membrane surface due to the reverse transport of NaCl draw solute. The increase in the humic acid deposition on the membrane surface led to a substantial decrease in the membrane salt (NaCl) permeability coefficient but did not result in a significant decrease in the …
Impact Of The Mlc On The Mri Field Distortion Of A Prototype Mri-Linac, Stefan Kolling, Brad Oborn, Paul Keall
Impact Of The Mlc On The Mri Field Distortion Of A Prototype Mri-Linac, Stefan Kolling, Brad Oborn, Paul Keall
Faculty of Engineering and Information Sciences - Papers: Part A
Purpose: To cope with intrafraction tumor motion, integrated MRI-linac systems for real-time image guidance are currently under development. The multileaf collimator (MLC) is a key component in every state-of-the-art radiotherapy treatment system, allowing for accurate field shaping and tumor tracking. This work quantifies the magnetic impact of a widely used MLC on the MRI field homogeneity for such a modality. Methods: Results: Conclusions: This work shows that the MRI field distortions caused by the MLC cannot be ignored and must be thoroughly investigated for any MRI-linac system. The numeric distortion values obtained for our1.0T magnet may vary for other magnet …
Impact Of Capacity Value Of Renewable Energy Resources On Raps System Energy Management, Y Tan, Kashem Muttaqi, Lasantha Meegahapola
Impact Of Capacity Value Of Renewable Energy Resources On Raps System Energy Management, Y Tan, Kashem Muttaqi, Lasantha Meegahapola
Faculty of Engineering and Information Sciences - Papers: Part A
Renewable energy resources are widely being utilised in remote area power supply (RAPS) systems. The capacity value of renewable energy resources in a RAPS system indicates the ability of renewable energy resources to serve the load demand in the RAPS systems. In this paper, the impact of capacity value of renewable resources on energy management of a RAPS system, while maintaining system reliability, is investigated. It is revealed that capacity value of renewable energy resources has direct influence on RAPS system energy management. By utilising storage in conjunction with renewable energy resources, the RAPS system can cater load demand while …
On The Residual Energy Toughness Of Prestressed Concrete Sleepers In Railway Track Structures Subjected To Repeated Impact Loads, Sakdirat Kaewunruen, Alexander Remennikov
On The Residual Energy Toughness Of Prestressed Concrete Sleepers In Railway Track Structures Subjected To Repeated Impact Loads, Sakdirat Kaewunruen, Alexander Remennikov
Faculty of Engineering and Information Sciences - Papers: Part A
Installed as the crosstie beam support in railway track systems, the prestressed concrete sleepers (or railroad ties) are designed in order to carry and transfer the wheel loads from the rails to the ground. It is nowadays best known that railway tracks are subject to the impact loading conditions, which are attributable to the train operations with either wheel or rail abnormalities such as flat wheels, dipped rails, etc. These loads are of very high magnitude but short duration, as well as there exists the potential of repeated load experience during the design life of the prestressed concrete sleepers. These …
Incremental Service Level Agreements Violation Handling With Time Impact Analysis, Azlan Ismail, Jun Yan, Jun Shen
Incremental Service Level Agreements Violation Handling With Time Impact Analysis, Azlan Ismail, Jun Yan, Jun Shen
Faculty of Engineering and Information Sciences - Papers: Part A
This research addresses a critical issue of service level agreement (SLA) violation handling, i.e., time constraint violation related to service-based systems (SBS). Whenever an SLA violation occurs to a service, it can potentially impact dependent services, leading to unreliable SBS. Therefore, an SLA violation handling support is much required to produce a robust and adaptive SBS. There are several approaches to realizing exceptions and faults handling support for SBS, focusing on the detection stage, the analysis stage, and the resolution stage. However, the current works have not considered the handling strategy that takes the impact information into account to reduce …
Environmental Impact Assessment Of Post Tensioned And Reinforced Concrete Slab Construction, D Miller, J H. Doh, H Guan, M Mulvey, S Fragomeni, T Mccarthy, T Peters
Environmental Impact Assessment Of Post Tensioned And Reinforced Concrete Slab Construction, D Miller, J H. Doh, H Guan, M Mulvey, S Fragomeni, T Mccarthy, T Peters
Faculty of Engineering and Information Sciences - Papers: Part A
In Australia, approximately 30 million tonnes of finished building products are produced each year, with over 56% of this quantity, by mass, being attributed to concrete and a further 6%, steel, highlighting the importance of maximising design efficiencies. The cement industry has been reported responsible for 5% of global carbon dioxide emissions while the construction, operation and maintenance of buildings are estimated to account for 50% of all energy usage and more than 50% of all anthropogenic greenhouse gas (GHG) emissions globally. This research determines some environmental advantages achievable through application of alternate concrete slab construction methods for a typical …