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Full-Text Articles in Social and Behavioral Sciences

State Of The Art Of Control Schemes For Smart Systems Featuring Magneto-Rheological Materials, Seung-Bok Choi, Weihua Li, Miao Yu, Haiping Du, Jie Fu, Phu Xuan Do Jan 2016

State Of The Art Of Control Schemes For Smart Systems Featuring Magneto-Rheological Materials, Seung-Bok Choi, Weihua Li, Miao Yu, Haiping Du, Jie Fu, Phu Xuan Do

Faculty of Engineering and Information Sciences - Papers: Part A

This review presents various control strategies for application systems utilizing smart magneto-rheological fluid (MRF) and magneto-rheological elastomers (MRE). It is well known that both MRF and MRE are actively studied and applied to many practical systems such as vehicle dampers. The mandatory requirements for successful applications of MRF and MRE include several factors: advanced material properties, optimal mechanisms, suitable modeling, and appropriate control schemes. Among these requirements, the use of an appropriate control scheme is a crucial factor since it is the final action stage of the application systems to achieve the desired output responses. There are numerous different control …


Learning Path Adaptation In Online Learning Systems, Alva Hendi Muhammad, Qingguo Zhou, Ghassan Beydoun, Dongming Xu, Jun Shen Jan 2016

Learning Path Adaptation In Online Learning Systems, Alva Hendi Muhammad, Qingguo Zhou, Ghassan Beydoun, Dongming Xu, Jun Shen

Faculty of Engineering and Information Sciences - Papers: Part A

Learning path in online learning systems refers to a sequence of learning objects which are designated to help the students in improving their knowledge or skill in particular subjects or degree courses. In this paper, we review the recent research on learning path adaptation to pursue two goals, first is to organize and analyze the parameter of adaptation in learning path; the second is to discuss the challenges in implementing learning path adaptation. The survey covers the state of the art and aims at providing a comprehensive introduction to the learning path adaptation for researchers and practitioners.


Balance Improvement Effects Of Biofeedback Systems With State-Of-The-Art Wearable Sensors: A Systematic Review, Christina Ma, Duo Wong, Wing K. Lam, Anson Wan, Winson Lee Jan 2016

Balance Improvement Effects Of Biofeedback Systems With State-Of-The-Art Wearable Sensors: A Systematic Review, Christina Ma, Duo Wong, Wing K. Lam, Anson Wan, Winson Lee

Faculty of Engineering and Information Sciences - Papers: Part A

Falls and fall-induced injuries are major global public health problems. Balance and gait disorders have been the second leading cause of falls. Inertial motion sensors and force sensors have been widely used to monitor both static and dynamic balance performance. Based on the detected performance, instant visual, auditory, electrotactile and vibrotactile biofeedback could be provided to augment the somatosensory input and enhance balance control. This review aims to synthesize the research examining the effect of biofeedback systems, with wearable inertial motion sensors and force sensors, on balance performance. Randomized and non-randomized clinical trials were included in this review. All studies …


Antenna Selection Strategies For Mimo-Ofdm Wireless Systems: An Energy-Efficiency Perspective, Ngoc Phuc Le, Farzad Safaei, Le Chung Tran Jan 2016

Antenna Selection Strategies For Mimo-Ofdm Wireless Systems: An Energy-Efficiency Perspective, Ngoc Phuc Le, Farzad Safaei, Le Chung Tran

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we investigate antenna selection strategies for MIMO-OFDM wireless systems from an energy efficiency perspective. We first derive closed-form expressions of the energy efficiency and the energy efficiency- spectral efficiency (EE-SE) trade-off in conventional antenna selection MIMO-OFDM systems. The obtained results show that these systems suffer from a significant loss in energy efficiency. To achieve a better energy-efficiency performance, we propose an adaptive antenna selection method where both the number of active RF (radio frequency) chains and the antenna indices are selected depending on the channel condition. This selection scheme could be implemented by an exhaustive search technique …


Learning Network Storage Curriculum With Experimental Case Based On Embedded Systems, Qingguo Zhou, Jiong Wu, Ting Wu, Jun Shen, Rui Zhou Jan 2016

Learning Network Storage Curriculum With Experimental Case Based On Embedded Systems, Qingguo Zhou, Jiong Wu, Ting Wu, Jun Shen, Rui Zhou

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we present an experimental case for the course of "Network Storage and Security," which benefited from an improved learning outcome for our students. The newly designed experiments-based contents are merged into the current course to help students obtain practical experiences about network storage. The experiments aim to build a network storage system based on available resources instead of any specialized network storage equipment. Technically, students can learn general practical knowledge of network storage on iSCSI (a network storage protocol based on IP technology) and also the technologies of embedded system. Through the experimental case, we found that …


Development Of A Novel Phase Change Material Emulsion For Cooling Systems, Jingjing Shao, Jo Darkwa, Georgios Kokogiannakis Jan 2016

Development Of A Novel Phase Change Material Emulsion For Cooling Systems, Jingjing Shao, Jo Darkwa, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, a novel phase change material emulsion (PCE-10) consisting of an organic PCM (RT10) and water has been developed. Its thermophysical properties such as heat of fusion, viscosity and sub-cooling temperature have been established. The chemical stability during both storage and discharge periods have also been evaluated. The results indicate low sub-cooling temperature and relatively long period of stability without any sign of segregation but the viscosity was found to be much higher than that of water.Further improvement and experimental studies into its flow characteristics are therefore being encouraged.


A Review Of Protection Systems For Distribution Networks Embedded With Renewable Generation, Joel Kennedy, Philip Ciufo, Ashish P. Agalgaonkar Jan 2016

A Review Of Protection Systems For Distribution Networks Embedded With Renewable Generation, Joel Kennedy, Philip Ciufo, Ashish P. Agalgaonkar

Faculty of Engineering and Information Sciences - Papers: Part A

The rapid growth of grid-connected embedded generation is changing the operational characteristics of power distribution networks. Amongst a range of issues being reported in the research, the effect of these changes on so-called 'traditional protection systems' has not gone without attention. Looking to the future, the possibility of microgrid systems and deliberate islanding of sections of the network will require highly flexible distribution management systems and a re-design of protection strategies. This paper explores the envisaged protection issues concerned with large penetrations of embedded generation in distribution networks extending into auto-reclosure and protection device coordination. A critical review of recently …


Msis 2016: A Comprehensive Update Of Graduate Level Curriculum Recommendation In Information Systems, Heikki Topi, Susan A. Brown, Joao Alvaro Carvalho, Brian Donnellan, Helena Karsten, Jun Shen, Bernard C. Y Tan, Mark F. Thouin Jan 2016

Msis 2016: A Comprehensive Update Of Graduate Level Curriculum Recommendation In Information Systems, Heikki Topi, Susan A. Brown, Joao Alvaro Carvalho, Brian Donnellan, Helena Karsten, Jun Shen, Bernard C. Y Tan, Mark F. Thouin

Faculty of Engineering and Information Sciences - Papers: Part A

The process to revise MSIS 2006, the master's level curriculum recommendation for Information Systems, is getting close to completion. In spring and summer 2016, the joint AIS/ACM task force will continue the process of soliciting comments from various stakeholders, including the academic IS community and employers. The purpose of the AMCIS panel is to give the audience an update of the status of the MSIS 2016 revision process and provide the task force with feedback regarding the draft document. A significant portion of the session will be reserved for conversation. The task force is proposing significant changes to the curriculum …


Looking Beyond Installation: Why Households Struggle To Make The Most Of Solar Hot Water Systems, Nicholas J. Gill, Peter Osman, Lesley M. Head, Michelle Voyer, Theresa Harada, Gordon R. Waitt, Christopher R. Gibson Jan 2015

Looking Beyond Installation: Why Households Struggle To Make The Most Of Solar Hot Water Systems, Nicholas J. Gill, Peter Osman, Lesley M. Head, Michelle Voyer, Theresa Harada, Gordon R. Waitt, Christopher R. Gibson

Faculty of Social Sciences - Papers (Archive)

This paper examines household responses to sustainability issues and adoption of energy saving technologies. Our example of solar hot water systems highlights the complexity and variability of responses to low-carbon technologies. While SHW systems have the potential to provide the majority of household hot water and to lower carbon emissions, little research has been done to investigate how SHW systems are integrated into everyday life. We draw on cultural understandings of the household to identify passive and active users of SHW systems and utilize a model that illustrates how technology use is dependent on inter-relations between cultural norms, systems of …


A Phantom Assessment Of Achievable Contouring Concordance Across Multiple Treatment Planning Systems, Elise M. Pogson, Jarrad Begg, Michael Jameson, Claire Dempsey, Drew Latty, Vikneswary Batumalai, Andrew Lim, Kankean Kandasamy, Peter E. Metcalfe, Lois C. Holloway Jan 2015

A Phantom Assessment Of Achievable Contouring Concordance Across Multiple Treatment Planning Systems, Elise M. Pogson, Jarrad Begg, Michael Jameson, Claire Dempsey, Drew Latty, Vikneswary Batumalai, Andrew Lim, Kankean Kandasamy, Peter E. Metcalfe, Lois C. Holloway

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, the highest level of inter- and intra-observer conformity achievable with different treatment planning systems (TPSs), contouring tools, shapes, and sites have been established for metrics including the Dice similarity coefficient (DICE) and Hausdorff Distance. High conformity values, e.g. DICEBreast_Shape = 0.99 ± 0.01, were achieved. Decreasing image resolution decreased contouring conformity.


Simulink Model For Examining Dynamic Interactions Involving Electro-Mechanical Oscillations In Distribution Systems, Dothinka Ranamuka Rallage, Ashish P. Agalgaonkar, Kashem M. Muttaqi Jan 2015

Simulink Model For Examining Dynamic Interactions Involving Electro-Mechanical Oscillations In Distribution Systems, Dothinka Ranamuka Rallage, Ashish P. Agalgaonkar, Kashem M. Muttaqi

Faculty of Engineering and Information Sciences - Papers: Part A

In Australian medium voltage (MV) distribution networks, the majority of embedded local generation (LG) uses synchronous machine based technology. LG units with a synchronous generator can easily be dispatched and controlled to provide or absorb reactive power and thereby locally supporting the system voltage and increasing the voltage stability margin. The fast response from a synchronous machine based LG unit exciter will ensure fast voltage recovery. This will significantly improve the transient voltage stability. Also, the synchronous machine based LG units can provide inertial support to the system. Furthermore, some of these LG technologies work as standby power supplies all …


Applications Of Magnetorheological Technology To Semiactive Vibration Control Systems, Miao Yu, Seung-Bok Choi, Norman M. Wereley, Weihua Li, Jeong-Hoi Koo, Xinchun Guan Jan 2015

Applications Of Magnetorheological Technology To Semiactive Vibration Control Systems, Miao Yu, Seung-Bok Choi, Norman M. Wereley, Weihua Li, Jeong-Hoi Koo, Xinchun Guan

Faculty of Engineering and Information Sciences - Papers: Part A

Semiactive vibration control systems possess both the simplicity and inherent reliability of passive systems while maintaining the adaptability of active vibration control systems integrated with an appropriate control algorithm. One of the recent and promising technologies in semiactive vibration control is to utilize magnetorheological (MR) fluids (MRFs) and MR elastomers (MREs). The well-known remarkable feature of MR materials is the continuous controllability of stiffness and damping properties under external magnetic field. The unique controllable characteristic of MR materials has catalyzed comprehensive research and development focusing on vibration control systems including vehicle dampers, engine mounts, adaptive tuned vibration absorber, and seismic …


Optimization Of The Number Of Rays In Interpolation For Light Field Based Free Viewpoint Systems, Hooman Shidanshidi, Farzad Safaei, Wanqing Li Jan 2015

Optimization Of The Number Of Rays In Interpolation For Light Field Based Free Viewpoint Systems, Hooman Shidanshidi, Farzad Safaei, Wanqing Li

Faculty of Engineering and Information Sciences - Papers: Part A

Light field (LF) rendering is widely used in free viewpoint video systems (FVV). Different methods have been proposed to employ depth maps to improve the rendering quality. However, estimation of depth is often error-prone. In this paper, a new method based on the concept of effective sampling density (ESD) is proposed for evaluating the depth-based LF rendering algorithms at different levels of errors in the depth estimation. In addition, for a given rendering quality, we provide an estimation of number of rays required in the interpolation algorithm to compensate for the adverse effect caused by errors in depth maps. The …


Modeling Minimum Transport Boundary For Fluidized Dense-Phase Pneumatic Conveying Systems, G Setia, Soumya Suddha Mallick, Renhu Pan, Peter W. Wypych Jan 2015

Modeling Minimum Transport Boundary For Fluidized Dense-Phase Pneumatic Conveying Systems, G Setia, Soumya Suddha Mallick, Renhu Pan, Peter W. Wypych

Faculty of Engineering and Information Sciences - Papers: Part A

For the reliable design of fluidized dense-phase pneumatic conveying systems, it is of paramount importance to accurately estimate blockage conditions or the minimum transport boundary. Existing empirical models for the fluidized dense-phase conveying of fine powders are either based on a limited number of products and pipelines or have not been tested for their accuracy and stability over a wide range of scale-up conditions. In this paper, based on the test results of 22 different powders conveyed through 38 pipelines, a unified model for the minimum transport boundary has been developed that represents gas Froude number as a function of …


A Survey Of Single And Multi-Hop Link Schedulers For Mmwave Wireless Systems, Jian Song, Kwan-Wu Chin Jan 2015

A Survey Of Single And Multi-Hop Link Schedulers For Mmwave Wireless Systems, Jian Song, Kwan-Wu Chin

Faculty of Engineering and Information Sciences - Papers: Part A

Wireless communication at 60. GHz, aka mmWave, provides extremely high data rates, i.e., several Gb/s. Moreover, devices have a much shorter transmission range as compared to those operating in the 2.4 and 5. GHz bands. Indeed, links can be treated as pseudo-wires with minimal interference leakage. As a result, future 60. GHz systems will have very high spatial reuse. This, however, is at the expense of high propagation loss, which can be overcome using directional or smart antennas. Another promising solution is to employ relays to boost the signal of weak links. In particular, if relays are properly selected, they …


On Transformation Of Query Scheduling Strategies In Distributed And Heterogeneous Database Systems, Janusz R. Getta, - Handoko Jan 2015

On Transformation Of Query Scheduling Strategies In Distributed And Heterogeneous Database Systems, Janusz R. Getta, - Handoko

Faculty of Engineering and Information Sciences - Papers: Part A

This work considers a problem of optimal query processing in heterogeneous and distributed database systems. A global query sub- mitted at a local site is decomposed into a number of queries processed at the remote sites. The partial results returned by the queries are in- tegrated at a local site. The paper addresses a problem of an optimal scheduling of queries that minimizes time spend on data integration of the partial results into the final answer. A global data model defined in this work provides a unified view of the heterogeneous data structures located at the remote sites and a …


Optimal Design For Energy-Efficient Per-Subcarrier Antenna Selection Mimo–Ofdm Wireless Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei Jan 2015

Optimal Design For Energy-Efficient Per-Subcarrier Antenna Selection Mimo–Ofdm Wireless Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we consider a novel optimal design for per-subcarrier antenna selection multi-input multi-output orthogonal frequency division multiplexing systems from an energy-efficiency perspective. The optimal number of antennas, i.e., the number of radio frequency chains, that needs to be built-in on a transmitter to achieve the maximum energy-efficiency is determined. Specifically, an optimization problem for maximizing the average energy-efficiency with respect to the number of antennas is formulated. To solve this optimization problem, we first derive a closed-form formula expressing the cost function (i.e., the average energy-efficiency) as a function of the number of antennas. Search algorithms are then …


Energy Efficiency Analysis Of Antenna Selection Multi-Input Multi-Output Automatic Repeat Request Systems Over Nakagami-M Fading Channels, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei, Vineeth Satheeskum Varma Jan 2015

Energy Efficiency Analysis Of Antenna Selection Multi-Input Multi-Output Automatic Repeat Request Systems Over Nakagami-M Fading Channels, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei, Vineeth Satheeskum Varma

Faculty of Engineering and Information Sciences - Papers: Part A

In this study, the authors investigate energy efficiency in antenna selection multi-input multi-output automatic repeat request (MIMO ARQ) wireless systems. The authors first derive an approximate expression for the average frame-error rate (FER) in antenna selection MIMO systems over quasi-static Nakagami-m fading channels. The FER approximation is then used to obtain an analytical expression of an energy-efficiency metric that is defined as the total energy required to successfully deliver one information bit. The authors prove that this energy-efficiency metric is a quasi-convex function with respect to the average signal-to-noise ratio value. Based on this analysis, the authors obtain the optimal …


Maximising Energy Efficiency In Antenna Selection Mimo Wireless Systems Subject To Qos Constraints, Ngoc Phuc Le, Farzad Safaei, Le Chung Tran Jan 2015

Maximising Energy Efficiency In Antenna Selection Mimo Wireless Systems Subject To Qos Constraints, Ngoc Phuc Le, Farzad Safaei, Le Chung Tran

Faculty of Engineering and Information Sciences - Papers: Part A

Energy-efficiency (EE) in antenna selection multi-input–multi-output (MIMO) systems over Nakagami-m fading channels is investigated. An EE metric is defined as the number of successfully received bits per unit of energy consumption, which takes into account several important system parameters such as channel coding and modulation. An optimisation problem that maximises the EE metric subject to an error-performance constraint is formulated. On the basis of an analysis of this problem, the optimal value of the average energy per transmitted data symbol is obtained, such that the EE in the system is maximised. Simulation results are provided to validate the analysis.


Evaluation Of 3d Gamma Index Calculation Implemented In Two Commercial Dosimetry Systems, Aitang Xing, Sankar Arumugam, Shrikant Deshpande, Armia George, Philip J. Vial, Lois C. Holloway, Gary Goozee Jan 2015

Evaluation Of 3d Gamma Index Calculation Implemented In Two Commercial Dosimetry Systems, Aitang Xing, Sankar Arumugam, Shrikant Deshpande, Armia George, Philip J. Vial, Lois C. Holloway, Gary Goozee

Faculty of Engineering and Information Sciences - Papers: Part A

3D Gamma index is one of the metrics which have been widely used for clinical routine patient specific quality assurance for IMRT, Tomotherapy and VMAT. The algorithms for calculating the 3D Gamma index using global and local methods implemented in two software tools: PTW-VeriSoft (R) r as a part of OCTIVIUS 4D dosimeter systems and 3DVH (TM) from Sun Nuclear were assessed. The Gamma index calculated by the two systems was compared with manual calculated for one data set. The Gamma pass rate calculated by the two systems was compared using 3%/3mm, 2%/2mm, 3%/2mm and 2%/3mm for two additional data …


Effective Utilization Of Excess Energy In Standalone Hybrid Renewable Energy Systems For Improving Comfort Ability And Reducing Cost Of Energy: A Review And Analysis, M Ismail Ismail, Mahmoud Moghavvemi, T Mahlia, Kashem M. Muttaqi, S Moghavvemi Jan 2015

Effective Utilization Of Excess Energy In Standalone Hybrid Renewable Energy Systems For Improving Comfort Ability And Reducing Cost Of Energy: A Review And Analysis, M Ismail Ismail, Mahmoud Moghavvemi, T Mahlia, Kashem M. Muttaqi, S Moghavvemi

Faculty of Engineering and Information Sciences - Papers: Part A

One of the features that characterize renewable energy sources is their variability and intermittency. Intermittency covers both the predictable and unpredictable variations of their power outputs and uncertainty in the power availability. To overcome the drawback of intermittency, special design considerations should be taken into account. These additional design considerations increases the overall cost of the renewable energy systems. Adding storage system and/or backup source to the renewable sources is one of the measures used to guarantee the continuity of power supply to the loads, and therefore improve the reliability of the renewable energy systems. The operation of renewable energy …


A Promising Set Of Spreading Sequences To Mitigate Mai Effects In Mimo Sts Systems, Anh Tuyen Le, Le Chung Tran, Prashan Premaratne, David Stirling, Beata J. Wysocki, Tadeusz A. Wysocki, Peter J. Vial Jan 2015

A Promising Set Of Spreading Sequences To Mitigate Mai Effects In Mimo Sts Systems, Anh Tuyen Le, Le Chung Tran, Prashan Premaratne, David Stirling, Beata J. Wysocki, Tadeusz A. Wysocki, Peter J. Vial

Faculty of Engineering and Information Sciences - Papers: Part A

Multiple input, Multiple output space time spreading (MIMO STS) system is a scheme which can provide full diversity gain without extra resource requirements. However, its performance degrades significantly when multiple access interference (MAI) occurs. In order to mitigate MAI effects, we propose a criterion to build a promising set of combination of spreading sequences for users. Simulation results show that the average BER performance of users using this promising set is about thirty percent lower than that of users using another set in case of 64 chip length Walsh-Hadamard code.


Enhanced Frequency Response Strategy For Pmsg Based Wind Energy Conversion System Using Ultracapacitor In Remote Area Power Supply Systems, Yingjie Tan, Kashem M. Muttaqi Jan 2015

Enhanced Frequency Response Strategy For Pmsg Based Wind Energy Conversion System Using Ultracapacitor In Remote Area Power Supply Systems, Yingjie Tan, Kashem M. Muttaqi

Faculty of Engineering and Information Sciences - Papers: Part A

The high penetration level of wind energy, and non-responsive nature of power electronic interfaced wind energy conversion system (WECS) during frequency variations may create significant stress on conventional generators in a wind-diesel hybrid remote area power supply (RAPS) system. Hence, it is a necessity for WECS to provide frequency support. However, conventional frequency control strategies being used for WECS may impose a severe stress to wind turbines. In this paper, an enhanced frequency response strategy is proposed for the permanent magnet synchronous generator (PMSG) based WECS to regulate RAPS system frequency jointly with its integrated ultracapacitors. The proposed frequency response …


Exact Error Performance Analysis Of Binary Space-Time Block Coded Cooperative Communications Systems In Rayleigh Fading Channels, Le Chung Tran, Zixuan Lin, Farzad Safaei, Alfred Mertins, Duy T. Ngo Jan 2015

Exact Error Performance Analysis Of Binary Space-Time Block Coded Cooperative Communications Systems In Rayleigh Fading Channels, Le Chung Tran, Zixuan Lin, Farzad Safaei, Alfred Mertins, Duy T. Ngo

Faculty of Engineering and Information Sciences - Papers: Part A

Cooperative communications using the Alamouti space-time block code (STBC) has been mentioned intensively. However, to our knowledge, an in-depth error performance analysis for a space-time coded cooperative communications system, where each node acts as both a source node and a relay node for its partner, has not been reported. Intuitively, cooperative communications would not always be better than direct transmission, but only under certain conditions. This paper first derives an exact performance analysis of the Alamouti STBC cooperative communications for a Binary Phase Shift Keying (BPSK) constellation, which could be extended to a higher density modulation scheme. This mathematical analysis …


Tuning Houses Through Building Management Systems, Jose Ripper Kos, Massimo Fiorentini, Paul Cooper, Felipe Miranda Jan 2014

Tuning Houses Through Building Management Systems, Jose Ripper Kos, Massimo Fiorentini, Paul Cooper, Felipe Miranda

Faculty of Engineering and Information Sciences - Papers: Part A

This paper departs from an analogy of sailing race instruments to demonstrate the potential of automation systems on the house performance and, more important, on impacting households for a more sustainable behavior. Sailing instruments have positively influenced the results on experienced sailors' speed and ultimately have confirmed their observations on nature cycles. We have presented two research projects for the development of Building Management Systems for a house that relies mostly on natural ventilation and thermal mass and another one, based on a complex conditioning system with a solar assited HVAC system, connected to a Phase Change Material thermal storage. …


Suboptimal Mppt Control For Power Management In Pv-Diesel Remote Area Power Supply Systems, Yingjie Tan, Lasantha G. Meegahapola, Kashem M. Muttaqi Jan 2014

Suboptimal Mppt Control For Power Management In Pv-Diesel Remote Area Power Supply Systems, Yingjie Tan, Lasantha G. Meegahapola, Kashem M. Muttaqi

Faculty of Engineering and Information Sciences - Papers: Part A

Maximum power point tracking (MPPT) is commonly being used in solar-photovoltaic (PV) power generation systems to maximise solar energy extraction. In this paper it is proposed to operate the solar-PV system at the suboptimal MPPT to manage power balance in a remote area power supply (RAPS) system. This is performed based on three different operating modes: 1) Frequency control mode; 2) Active power control mode; 3) MPPT control mode. The operating modes are decided based on the load level and the operating mode of the diesel generator (i.e. synchronous condenser mode or generator mode). This power management strategy balances the …


Characterizing Artificial Socio-Cognitive Technical Systems, Rob Christiaanse, Aditya K. Ghose, Pablo Noriega, Munindar P. Singh Jan 2014

Characterizing Artificial Socio-Cognitive Technical Systems, Rob Christiaanse, Aditya K. Ghose, Pablo Noriega, Munindar P. Singh

Faculty of Engineering and Information Sciences - Papers: Part A

This paper is an invitation to examine a class of socio-technical systems - artificial socio-cognitive (ASCS) - whose distinctive nature is that they may involve humans as well as artificial agents who interact in a regulated milieu. We propose a characterization of these ASCS and build on that characterization to describe how these systems evolve.


Towards A Cryptographic Treatment Of Publish/Subscribe Systems, Tsz Hon Yuen, Willy Susilo, Yi Mu Jan 2014

Towards A Cryptographic Treatment Of Publish/Subscribe Systems, Tsz Hon Yuen, Willy Susilo, Yi Mu

Faculty of Engineering and Information Sciences - Papers: Part A

Publish/subscribe mechanism is a typical many-to-many messaging paradigm when multiple applications want to receive the same message or when a group of applications would like to notify each other. Nonetheless, there exist only a few works that address the security issues for content-based publish/subscribe systems formally. Although the security requirements have been partially addressed by Wang et al., there is no formal definition for all of these security requirements in the literature. As a result, most of the existing schemes do not have any security proof and it is difficult to justify whether those schemes are really secure in practice. …


Adaptive Antenna Selection For Energy-Efficient Mimo-Ofdm Wireless Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei Jan 2014

Adaptive Antenna Selection For Energy-Efficient Mimo-Ofdm Wireless Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we investigate energy-efficiency in antenna selection OFDM-based systems. We show that an OFDM system with conventional antenna selection approaches, including per-subcarrier selection (i.e., selecting antennas independently for each subcarrier) and bulk-selection (i.e., choosing the same antennas for all subcarriers), suffers from a significant loss in energy-efficiency. To achieve a better energy-efficiency performance, we propose an adaptive antenna selection scheme where both the number of active RF (radio frequency) chains and the antenna indices are selected depending on the channel condition. This selection scheme could be implemented by exhaustive search. Moreover, we develop an algorithm that achieves a …


A Comparative Analysis Of Multichannel Data Acquisition Systems For Quality Assurance In External Beam Radiation Therapy, Iolanda Fuduli, Claudiu Porumb, Anthony Espinoza, Abdullah Aldosari, Martin Carolan, Michael Lf Lerch, Peter E. Metcalfe, Anatoly Rosenfeld, Marco Petasecca Jan 2014

A Comparative Analysis Of Multichannel Data Acquisition Systems For Quality Assurance In External Beam Radiation Therapy, Iolanda Fuduli, Claudiu Porumb, Anthony Espinoza, Abdullah Aldosari, Martin Carolan, Michael Lf Lerch, Peter E. Metcalfe, Anatoly Rosenfeld, Marco Petasecca

Faculty of Engineering and Information Sciences - Papers: Part A

The paper presents a comparative study performed by the Centre of Medical Radiation Physics (CMRP) on three multichannel Data Acquisition Systems (DAQ) based on different analogue front-ends to suit a wide range of radiotherapy applications. The three front-ends are: a charge-to-frequency converter developed by INFN Torino, an electrometer and a charge-to-digital converter (both commercial devices from Texas Instruments). For the first two (named DAQ A and B), the CMRP has designed the read-out systems whilst the third one (DAQ C) comes with its own evaluation board. For the purpose of the characterization DAQ A and DAQ B have been equipped …