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Full-Text Articles in Social and Behavioral Sciences
Energy-Efficiency Analysis Of Per-Subcarrier Antenna Selection With Peak-Power Reduction In Mimo-Ofdm Wireless Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei
Energy-Efficiency Analysis Of Per-Subcarrier Antenna Selection With Peak-Power Reduction In Mimo-Ofdm Wireless Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei
Faculty of Engineering and Information Sciences - Papers: Part A
The use of per-subcarrier antenna subset selection in OFDM wireless systems offers higher system capacity and/or improved link reliability.However, the implementation of the conventional per-subcarrier selection schememay result in significant fluctuations of the average power and peak power across antennas, which affects the potential benefits of the system. In this paper, power efficiency of high-power amplifiers and energy efficiency in per-subcarrier antenna selection MIMO-OFDM systems are investigated. To deliver the maximum overall power efficiency, we propose a two-step strategy for data-subcarrier allocation.This strategy consists of an equal allocation of data subcarriers based on linear optimization and peak-power reduction via cross-antenna …
A Comparison Of Coordinate Systems For Use In Determining A Radiotherapy Delineation Margin For Whole Breast, Elise Pogson, Lauren Bell, Vikneswary Batumalai, Eng-Siew Koh, Geoff Delaney, Peter E. Metcalfe, Lois Holloway
A Comparison Of Coordinate Systems For Use In Determining A Radiotherapy Delineation Margin For Whole Breast, Elise Pogson, Lauren Bell, Vikneswary Batumalai, Eng-Siew Koh, Geoff Delaney, Peter E. Metcalfe, Lois Holloway
Faculty of Engineering and Information Sciences - Papers: Part A
Cartesian co-ordinates, traditionally used for radiotherapy margins, calculated at 6 points, may not adequately represent changes in inter-observer contour variation as necessary to define a delineation margin. As a first step, this study compared the standard deviation (SD) in contour delineation using Polar and Cartesian co-ordinates for whole breast. Whole breast Clinical Target Volumes (CTV) were delineated by eight observers for 9 patients. The SD of contour position was determined for Polar co-ordinates at 1 degree increments for 5 slices and averaged across all patients. The mean centre of mass (COM) was used as the origin for the right breast, …
A Review Of Technical Challenges In Planning And Operation Of Remote Area Power Supply Systems, Yingjie Tan, Lasantha Meegahapola, Kashem M. Muttaqi
A Review Of Technical Challenges In Planning And Operation Of Remote Area Power Supply Systems, Yingjie Tan, Lasantha Meegahapola, Kashem M. Muttaqi
Faculty of Engineering and Information Sciences - Papers: Part A
Remote area power supply (RAPS) systems are being used for many years to supply power to rural or remote communities where the utility grid is not accessible. In order to avoid the high operating cost and environmental impact caused by conventional generators, renewable energy resources are currently being utilised in RAPS systems. However, the intermittency of such renewable energy resources greatly impacts on planning and operation of RAPS systems. This paper aims to present a comprehensive review with regard to the RAPS system planning and operation techniques published in the literature. This paper summarises different modelling approaches associated with the …
Free Vibrations Of Interspersed Railway Track Systems In Three-Dimensional Space, Sakdirat Kaewunruen, Alexander Remennikov, Akira Aikawa, Hirotaka Sakai
Free Vibrations Of Interspersed Railway Track Systems In Three-Dimensional Space, Sakdirat Kaewunruen, Alexander Remennikov, Akira Aikawa, Hirotaka Sakai
Faculty of Engineering and Information Sciences - Papers: Part A
Statistically, the actual loading conditions for railway tracks are rather dynamic and transient. The dynamic loadings due to train and track interactions redistribute from the rails to the rail pad, from the rail pad to the railway sleeper, and from the railway sleeper to the underlying ground. Commonly, railway sleeper in track systems is modeled as a beam on elastic foundation. This study makes use of a calibrated finite element model of railway sleepers in a track system, in order to investigate the resonant frequencies and associated mode shapes of railway components in interspersed track systems. The numerical model takes …
Variation Of Poincare Recurrence Times In Discrete Dynamical Systems, Mimoon Ismael, Rodney Nillsen, Graham H. Williams
Variation Of Poincare Recurrence Times In Discrete Dynamical Systems, Mimoon Ismael, Rodney Nillsen, Graham H. Williams
Faculty of Engineering and Information Sciences - Papers: Part A
This paper is concerned with the variation and standard deviation of recurrence times in discrete dynamical systems.
Learning Diagnostic Diagrams In Transport-Based Data-Collection Systems, Vu Tran, Peter W. Eklund, Christopher David Cook
Learning Diagnostic Diagrams In Transport-Based Data-Collection Systems, Vu Tran, Peter W. Eklund, Christopher David Cook
Faculty of Engineering and Information Sciences - Papers: Part A
Insights about service improvement in a transit network can be gained by studying transit service reliability. In this paper, a general procedure for constructing a transit service reliability diagnostic (Tsrd) diagram based on a Bayesian network is proposed to automatically build a behavioural model from Automatic Vehicle Location (AVL) and Automatic Passenger Counters (APC) data. Our purpose is to discover the variability of transit service attributes and their effects on traveller behaviour. A Tsrd diagram describes and helps to analyse factors affecting public transport by combining domain knowledge with statistical data.
Towards A Cryptographic Treatment Of Publish/Subscribe Systems, Tsz Hon Yuen, Willy Susilo, Yi Mu
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. …
Applications Of Controllable Smart Fluids To Mechanical Systems, Seung-Bok Choi, Norman Wereley, Weihua Li, Miao Yu, Jeong-Hoi Koo
Applications Of Controllable Smart Fluids To Mechanical Systems, Seung-Bok Choi, Norman Wereley, Weihua Li, Miao Yu, Jeong-Hoi Koo
Faculty of Engineering and Information Sciences - Papers: Part A
For this special issue, 20 papers have been received, and three of which have been withdrawn. After strict review processes by the world-wide experts on the smart fluids technology, 10 papers have been accepted and are published here.The published papers cover various application devices and systems, which can be controllable to achieve desired performances by applying the external fields to the smart fluid domains. A brief summary of each application item proposed in the published papers is given as follows.
Adaptive Antenna Selection For Energy-Efficient Mimo-Ofdm Wireless Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei
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 …
Suboptimal Mppt Control For Power Management In Pv-Diesel Remote Area Power Supply Systems, Yingjie Tan, Lasantha G. Meegahapola, Kashem M. Muttaqi
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
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.
Tuning Houses Through Building Management Systems, Jose Ripper Kos, Massimo Fiorentini, Paul Cooper, Felipe Miranda
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. …
A Review Of Data Quality Assessment Methods For Public Health Information Systems, Hong Chen, David Hailey, Ning Wang, Ping Yu
A Review Of Data Quality Assessment Methods For Public Health Information Systems, Hong Chen, David Hailey, Ning Wang, Ping Yu
Faculty of Engineering and Information Sciences - Papers: Part A
High quality data and effective data quality assessment are required for accurately evaluating the impact of public health interventions and measuring public health outcomes. Data, data use, and data collection process, as the three dimensions of data quality, all need to be assessed for overall data quality assessment. We reviewed current data quality assessment methods. The relevant study was identified in major databases and well-known institutional websites. We found the dimension of data was most frequently assessed. Completeness, accuracy, and timeliness were the three most-used attributes among a total of 49 attributes of data quality. The major quantitative assessment methods …
Power Allocation Algorithm In Ofdm-Based Cognitive Radio Systems, Van Vinh Nguyen, Yang Shouyi, Le Chung Tran
Power Allocation Algorithm In Ofdm-Based Cognitive Radio Systems, Van Vinh Nguyen, Yang Shouyi, Le Chung Tran
Faculty of Engineering and Information Sciences - Papers: Part A
In orthogonal frequency division multiplexing (OFDM)-based cognitive radio (CR) systems, the optimized algorithms for sub-carrier power allocation face the problems of complex iterative calculation and difficult realization. In this paper, we propose an exponential power distribution function and derive a sub-optimal power allocation algorithm. This algorithm aims to allocate power of in-band subcarriers of cognitive users according to the numerical characteristics of the power distribution function by using a convex optimization numerical method under linear constraints. This algorithm has the advantages of fast calculation speed and easy realization, and reduces the interference to the authorized users, which is caused by …
Transmit Antenna Subset Selection For High-Rate Mimo-Ofdm Systems In The Presence Of Nonlinear Power Amplifiers, Phuc Ngoc Le, Farzad Safaei, Le Chung Tran
Transmit Antenna Subset Selection For High-Rate Mimo-Ofdm Systems In The Presence Of Nonlinear Power Amplifiers, Phuc Ngoc Le, Farzad Safaei, Le Chung Tran
Faculty of Engineering and Information Sciences - Papers: Part A
The deployment of antenna subset selection on a per-subcarrier basis in MIMO-OFDM systems could improve the system performance and/or increase data rates. This paper investigates this technique for the MIMO-OFDM systems suffering nonlinear distortions due to high-power amplifiers. At first, some problems pertaining to the implementation of this antenna selection approach, including power imbalance across transmit antennas and non-causality of per-subcarrier antenna selection criteria, are identified. Next, an optimal selection scheme is devised by means of linear optimization to overcome those disadvantages. This scheme optimally allocates data subcarriers under a constraint that all antennas have the same number of data …
Aligning Ontology-Based Development With Service Oriented Systems, Jun Shen, Ghassan Beydoun, Graham Low, Lijuan Wang
Aligning Ontology-Based Development With Service Oriented Systems, Jun Shen, Ghassan Beydoun, Graham Low, Lijuan Wang
Faculty of Engineering and Information Sciences - Papers: Part A
This paper argues for placing ontologies at the centre of the software development life cycle for distributed component-based systems and, in particular, for service-oriented systems. It presents an ontology-based development process which relies on three levels of abstraction using ontologies: architecture layer, application layer and domain layer. The paper discusses the key roles of ontologies with respect to the various abstraction layers and their corresponding impact on the concomitant workproducts. In addition, a peer-to-peer-based service selecting and composing tool is suggested as a way of supporting the process. The paper presents the architecture of the proposed tool and illustrates the …
Online Voltage Control In Distribution Systems With Multiple Voltage Regulating Devices, Dothinka Ranamuka Rallage, Ashish Agalgaonkar, Kashem Muttaqi
Online Voltage Control In Distribution Systems With Multiple Voltage Regulating Devices, Dothinka Ranamuka Rallage, Ashish Agalgaonkar, Kashem Muttaqi
Faculty of Engineering and Information Sciences - Papers: Part A
Voltage regulation in distribution systems is typically performed with the aid of multiple voltage regulating devices, such as on-load tap changer and step voltage regulators. These devices are conventionally tuned and locally coordinated using Volt/VAR optimization strategies in accordance with the time-graded operation. However, in case of distribution systems with distributed generation (DG), there could be a possibility of simultaneous responses of DG and multiple voltage regulators for correcting the target bus voltage, thereby resulting in operational conflicts. This paper proposes an online voltage control strategy for a realistic distribution system containing a synchronous machine-based renewable DG unit and other …
Transmit Antenna Subset Selection With Power Balancing For High Data Rate Mimo-Ofdm Uwb Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei
Transmit Antenna Subset Selection With Power Balancing For High Data Rate Mimo-Ofdm Uwb Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei
Faculty of Engineering and Information Sciences - Papers: Part A
This paper proposes per-subcarrier transmit antenna subset selection with power balancing for MIMO-OFDM UWB systems to simultaneously improve the system error performance and increase data rates. The deployment of the per-subcarrier antenna subset selection may result in a power unbalance across antennas, which could cause power amplifiers (PAs) to operate in their non-linear regions. To overcome this disadvantage, we formulate a linear optimization problem for the optimal allocation of data subcarriers under a constraint that all antennas have the same number of assigned data symbols. This optimization problem could be applied to systems with an arbitrary number of multiplexed data …
Is 'Community' Important For Community Information Systems?, Alison E. Freeman, Peter Hyland, Mark Freeman, Karlheinz Kautz
Is 'Community' Important For Community Information Systems?, Alison E. Freeman, Peter Hyland, Mark Freeman, Karlheinz Kautz
Faculty of Engineering and Information Sciences - Papers: Part A
Community information systems have the power to transform communities. However, without fully understanding the pre-requisite factors affecting community information system viability, and the complex relationships between these factors, communities struggle to manage such projects in a way that leads to viable systems that deliver real benefits. This paper develops and presents a Model of Community Information System Viability Pre-requisite Factors, based on both existing literature and the study of three community information system projects. This Model represents the generic factors that inform viability (i.e. leadership, active membership, funding, awareness, and system design and functionality), and also considers the impact of …
On The Effects Of Spreading Sequences Over Mimo Systems, Tianle Liu, David A. Stirling, Le Chung Tran, Tadeusz A. Wysocki, Beata J. Wysocki, Prashan Dissanayake Mudiyanselage,, Peter James Vial
On The Effects Of Spreading Sequences Over Mimo Systems, Tianle Liu, David A. Stirling, Le Chung Tran, Tadeusz A. Wysocki, Beata J. Wysocki, Prashan Dissanayake Mudiyanselage,, Peter James Vial
Faculty of Engineering and Information Sciences - Papers: Part A
In this paper, we develop a Software Defined Radio (SDR) test bed to evaluate the Multiple Access Interference (MAI) effects over SISO and 2 x 1MIMO systems. It can be observed that under asynchronous transmissions, the Gold code leads to the best performance over both systems due to the fact that it has the best correlation properties. We also find the MAI effects in terms of the spreading sequences pairs on MIMO-STS systems. We propose a criterion for selecting promising spreading sequences for MIMO systems. Based on the measured results, we identify pairs of spreading sequences which have improved BER …
Power Sharing Among Multiple Solar Photovoltaic (Pv) Systems In A Radial Distribution Feeder, Brian K. Perera, Philip Ciufo
Power Sharing Among Multiple Solar Photovoltaic (Pv) Systems In A Radial Distribution Feeder, Brian K. Perera, Philip Ciufo
Faculty of Engineering and Information Sciences - Papers: Part A
With an increasing penetration of solar photovoltaic (PV) systems, power distribution grids are becoming more susceptible to network voltage rise. As per applicable standards for grid-integrated PV systems, a PV system must be automatically disconnected from the grid when the terminal voltage of the PV system exceeds a defined maximum voltage. With this directive, in certain situations, PV systems connected at nodes at which the voltage sensitivity is high, may be disconnected from the grid while PV systems connected at less sensitive nodes are continuing to operate. In such a situation, owners whose PV systems are connected at nodes at …
Efficient And Dynamic Key Management For Multiple Identities In Identity-Based Systems, Hua Guo, Chang Xu, Zhoujun Li, Yanqing Yao, Yi Mu
Efficient And Dynamic Key Management For Multiple Identities In Identity-Based Systems, Hua Guo, Chang Xu, Zhoujun Li, Yanqing Yao, Yi Mu
Faculty of Engineering and Information Sciences - Papers: Part A
The traditional identity-based cryptography requires a user, who holds multiple identities, to hold multiple private keys, where each private key is associated with an identity. Managing multiple private/public keys is a heavy burden to a user due to key management and storage. The recent advancement of identity-based cryptography allow a single private key to map multiple public keys (identities); therefore the private key management is simplified. Unfortunately, the existing schemes capturing this feature do not allow dynamic changes of identities and have a large data size proportional to the number of the associated identities. To overcome these problems, in this …
Combined Adaptive Lattice Reduction-Aided Detection And Antenna Shuffling For Dsttd-Ofdm Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei
Combined Adaptive Lattice Reduction-Aided Detection And Antenna Shuffling For Dsttd-Ofdm Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei
Faculty of Engineering and Information Sciences - Papers: Part A
In this paper, we consider lattice reduction (LR) aided linear detection in a DSTTD-OFDM (double space-time transmit diversity- orthogonal frequency division multiplexing) system with antenna shuffling. We first derive an antenna shuffling criterion for the LR-aided DSTTD-OFDM system. Next, we propose a combined reduced-feedback and adaptive LR algorithm by exploiting the correlation between OFDM subcarriers in the frequency domain. The LR-aided DSTTD OFDM system with this algorithm requires low computational effort for the LR operation and small feedback information. Simulation results show that a significant improvement could be achieved in the proposed system compared to previous (non-LR-aided) systems under spatially …
Spectral Triples For Hyperbolic Dynamical Systems, Michael F. Whittaker
Spectral Triples For Hyperbolic Dynamical Systems, Michael F. Whittaker
Faculty of Engineering and Information Sciences - Papers: Part A
Spectral triples are defined for C-algebras associated with hyperbolic dynam- ical systems known as Smale spaces. The spectral dimension of one of these spectral triples is shown to recover the topological entropy of the Smale space.
Mitigation Of Rooftop Solar Pv Impacts And Evening Peak Support By Managing Available Capacity Of Distributed Energy Storage Systems, Md Jan-E- Alam, Kashem Muttaqi, Darmawan Soetanto
Mitigation Of Rooftop Solar Pv Impacts And Evening Peak Support By Managing Available Capacity Of Distributed Energy Storage Systems, Md Jan-E- Alam, Kashem Muttaqi, Darmawan Soetanto
Faculty of Engineering and Information Sciences - Papers: Part A
A high penetration of rooftop solar photovoltaic (PV) resources into low-voltage (LV) distribution networks creates reverse power-flow and voltage-rise problems. This generally occurs when the generation from PV resources substantially exceeds the load demand during high insolation period. This paper has investigated the solar PV impacts and developed a mitigation strategy by an effective use of distributed energy storage systems integrated with solar PV units in LV networks. The storage is used to consume surplus solar PV power locally during PV peak, and the stored energy is utilized in the evening for the peak-load support. A charging/discharging control strategy is …
The Game Of Information Systems Higher Education, Mark Freeman, Alison E. Freeman
The Game Of Information Systems Higher Education, Mark Freeman, Alison E. Freeman
Faculty of Engineering and Information Sciences - Papers: Part A
With continual changes in higher education in the field of Information Systems (IS), educators are faced with the question: how can we actively engage each learner in a way that encourages self-direction while developing the ability to independently solve problems? The unique learning characteristics of adult learners must each be considered in the design of learning experiences in higher education environments. Gamification - the use of gaming elements in non-gaming contexts - is one source of opportunities for new and interesting learning experiences. Through discussion of 12 major gaming elements, this paper considers whether gamification can create innovative learning environments …
A Reflective Closed Loop Approach For Implementing A New Authentic Assessment-Based Teaching Facility For Electric Motor And Drive Systems, Craig Mclauchlan, Philip Ciufo, Sarath Perera
A Reflective Closed Loop Approach For Implementing A New Authentic Assessment-Based Teaching Facility For Electric Motor And Drive Systems, Craig Mclauchlan, Philip Ciufo, Sarath Perera
Faculty of Engineering and Information Sciences - Papers: Part A
BACKGROUND A new teaching facility with a focus on electric motor and drive systems has been implemented at the University of Wollongong. This facility aspires to use authentic assessment principles to assist in preparing students to properly utilise electric motor and drive systems in professional practice. In an attempt to realise this aim, the implementation of this facility was undertaken using a reflective closedloop approach, addressing the educational outcomes achieved by the students. Setting a holistic scope for the implementation beyond technical concerns to include educational outcomes was critical to the success achieved and has laid the foundation for further …
Application Of Multiple Objective Particle Swarm Optimisation In The Design Of Damaged Offshore Mooring Systems, Zhuo Wang, Timothy J. Mccarthy, M Neaz Sheikh
Application Of Multiple Objective Particle Swarm Optimisation In The Design Of Damaged Offshore Mooring Systems, Zhuo Wang, Timothy J. Mccarthy, M Neaz Sheikh
Faculty of Engineering and Information Sciences - Papers: Part A
The offshore hydrocarbon industry operates in more hostile environments as more of marginal fields become economically viable. This means that more floating production systems and economical mooring systems will be needed. With this increase in the use of marginal fields goes the need to re-use vessels and moorings. Floating production systems, such as FPSO's, need to survive extreme events and extreme damage conditions. When one mooring line is damaged, the remaining ones must be sufficient to avoid a complete failure and still protect critical components such as the riser. This paper looks into applying an evolutionary optimisation technique, namely multiple …
Double Space-Time Transmit Diversity For Very High Data Rate Mb-Ofdm Uwb Systems, Ngoc P. Le, Le C. Tran, Farzad Safaei
Double Space-Time Transmit Diversity For Very High Data Rate Mb-Ofdm Uwb Systems, Ngoc P. Le, Le C. Tran, Farzad Safaei
Faculty of Engineering and Information Sciences - Papers: Part A
In this paper, we investigate a multiband-orthogonal frequency division multiplexing ultra-wideband (MB-OFDM UWB) system with very high data rates (VHDR) of several gigabits per second (Gbps). We propose a DSTTD-based VHDR MB-OFDM UWB system by incorporating a double space-time transmit diversity (DSTTD) scheme into the conventional MB-OFDM UWB system. At the receiver, an efficient soft-demapper that takes into consideration the noise enhancement due to a zero-forcing equalization is developed. Numerical simulations of the proposed system at a very high data rate of 2.Gbps over the IEEE 802.15.3a channel models are implemented. The simulation results show that this system could achieve …
Information Systems Development Projects As Complex Adaptive Systems, Karlheinz Kautz
Information Systems Development Projects As Complex Adaptive Systems, Karlheinz Kautz
Faculty of Engineering and Information Sciences - Papers: Part A
This research considers information systems development (ISD) projects as complex adaptive systems. We investigate the question whether complex adaptive systems (CAS) theory is relevant as a theoretical foundation for understanding ISD, and if so, which kind of understanding can be achieved by utilizing the theory? We introduce key concepts of CAS theory such as interaction, emergence, interconnected autonomous agents, selforganization, co-evolution, poise at the edge of chaos, time pacing, and poise at the edge of time to analyse and understand ISD in practice. We demonstrate the strength of such a CAS approach through an empirical case study presentation and analysis. …