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Full-Text Articles in Engineering
Embracing Social Uncertainties With Complex Systems Science, Pascal Perez
Embracing Social Uncertainties With Complex Systems Science, Pascal Perez
SMART Infrastructure Facility - Papers
Human ecosystems are real-life systems characterized by very strong and longterm interactions between human communities and their environment; as such they constitute an expansion of the ecological concept of ecosystem. According to Stepp and colleagues (2003), human ecosystems not only process matter and energy flows, but - and more specifically - information flows as well. Therefore, they display very specific characteristics due to our ability to communicate and learn from others, creating the conditions for co-evolutionary processes in which chance lends a hand to necessity. Bradbury (2006) argues that, until recently, human beings had been able to adapt to changes …
Evolution Analysis Of Low-Cost Iterative Equalization In Coded Linear Systems With Cyclic Prefixes, Xiaojun Yuan, Qinghua Guo, Xiaodong Wang, Li Ping
Evolution Analysis Of Low-Cost Iterative Equalization In Coded Linear Systems With Cyclic Prefixes, Xiaojun Yuan, Qinghua Guo, Xiaodong Wang, Li Ping
Faculty of Engineering and Information Sciences - Papers: Part A
This paper is concerned with the low-cost iterative equalization/detection principles for coded linear systems with cyclic prefixes. Turbo frequency-domain-equalization (FDE) is applied to systems that may contain the joint effect of multiple-access interference (MAI), cross-antenna interference (CAI) and inter-symbol interference (ISI). We develop an SNK-variance evolution technique for the performance evaluation of the proposed systems. Numerical results in various channel environments demonstrate excellent agreement between the predicted and simulated system performance. © 2008 IEEE.
Performance Analysis Of Multi-Ary Systems With Iterative Linear Minimum-Mean-Square-Error Detection, Li Ping, Jun Tong, Xiaojun Yuan, Qinghua Guo
Performance Analysis Of Multi-Ary Systems With Iterative Linear Minimum-Mean-Square-Error Detection, Li Ping, Jun Tong, Xiaojun Yuan, Qinghua Guo
Faculty of Engineering and Information Sciences - Papers: Part A
This paper is concerned with coded multi-ary systems over linear channels. Based on a semi-analytical evolution technique, the impact of signaling schemes on the performance of low-cost iterative linear minimum-mean-square-error (LMMSE) detection is studied. It is shown that superposition coded modulation (SCM) maximizes the output signal-to-noise ratio (SNR) of LMMSE detectors. Consequently, SCM may potentially outperform other conventional signaling schemes when LMMSE detectors are used. Numerical examples are provided to verify the theoretical analysis. © 2008 IEEE.
Performance Analysis Of Ofdm-Idma Systems With Peak-Power Limitation, Jun Tong, Qinghua Guo, Li Ping
Performance Analysis Of Ofdm-Idma Systems With Peak-Power Limitation, Jun Tong, Qinghua Guo, Li Ping
Faculty of Engineering and Information Sciences - Papers: Part A
This paper is concerned with orthogonal frequency-division multiplexing interleave-division multiple-access (OFDM-IDMA) systems over frequency-selective fading channels. Deliberate clipping is applied to reduce the peak-to-average power ratio (PAPR) of each user's transmitted signal. An iterative multiuser detection (MUD) technique is developed to recover the performance loss due to clipping. A semi-analytical signal-to- noise ratio (SNR) evolution technique is proposed, which can provide quick and accurate prediction of the iterative MUD performance. Numerical results show that the performance of OFDM-IDMA is not sensitive to the frequency selectivity of channels, and OFDM-IDMA is more power-efficient than other alternative multi-carrier transmission techniques. © 2008 …
Referring Expression Generation Challenge 2008 Dit System Description, John D. Kelleher, Brian Mac Namee
Referring Expression Generation Challenge 2008 Dit System Description, John D. Kelleher, Brian Mac Namee
Conference papers
This section describes the two systems developed at DIT for the attribute selection track of the REG 2008 challenge. Both of theses systems use an incremental greedy search to generate descriptions, similar to the incremental algorithm described in (Dale and Reiter, 1995). The output of these incremental algorithms are, to a large extent, determined by the order in which the algorithm tests the target object’s attributes for inclusion in the description. Indeed, the major difference between the two systems described in this section is the mechanism used to order the attributes for inclusion.
Cfd Analysis Of The Performance Of Blade Cascades For Air Turbines In Oscillating Water Column Wave Energy Conversion Systems, Andrei Gareev, Paul Cooper, Prabuono B. Kosasih
Cfd Analysis Of The Performance Of Blade Cascades For Air Turbines In Oscillating Water Column Wave Energy Conversion Systems, Andrei Gareev, Paul Cooper, Prabuono B. Kosasih
Faculty of Engineering - Papers (Archive)
This paper presents the results of a detailed CFD (Computational Fluid Dynamics) analysis of the performance of blade cascades in reversing flow axial flow turbines for use as power take-off systems in Oscillating Water Column (OWC) Wave Energy Conversion (WEC) systems. In the first part of the paper a fundamental CFD analysis of the lift and drag data for various aerofoil profiles, using a number of different turbulence models, is described and quantitative comparisons are made with experimental data previously published by other researchers. The second part of the paper then describes CFD results of the performance of various rotors …