School of Information Technology and Electrical Engineering Publications  UQ eSpace
http://espace.library.uq.edu.au/
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A class of selfstabilizing MCA learning algorithms
http://espace.library.uq.edu.au/view/UQ:81391
In this letter, we propose a class of selfstabilizing learning algorithms for minor component analysis (MCA), which includes a few wellknown MCA learning algorithms. Selfstabilizing means that the sign of the weight vector length change is independent of the presented input vector. For these algorithms, rigorous global convergence proof is given and the convergence rate is also discussed. By combining the positive properties of these algorithms, a new learning algorithm is proposed which can improve the performance. Simulations are employed to confirm our theoretical results.
20070815T09:43:19Z
Ye, M.; Fan, X. Q.; Li, X.

A closed form solution to the reconstruction and multiview constraints of the degree d apparant contour
http://espace.library.uq.edu.au/view/UQ:99333
20070824T10:21:44Z
McKinnon, D. N. R.; Jones, B. D.; Lovell, B. C.

A Closed Form Solution to the Reconstruction and MultiView Constraints of the Degree d Apparent Contour
http://espace.library.uq.edu.au/view/UQ:10957
This paper presents a novel theoretical approach to calculating the apparent contour of a smooth surface. The problem is formulated as a dual space intersection of algebraic tangent cones, which we will consider to be the members of degree d hypersurfaces. The well known theoretical foundation for multiview geometry is extended in light of this to solve the problems of triangulation and forming multiview matching constraints for degree d apparent contours.
20040206T00:00:00Z
McKinnon, David; Jones, Barry; Lovell, Brian C.

A CMOS relative ultrasound energy measurement circuit with temperature compensation
http://espace.library.uq.edu.au/view/UQ:237610
CMOS temperature compensated circuit used in measuring relative ultrasound energy is presented in this paper. The core of the circuit is a temperature compensated voltage to current squarer (VCSQ) and a current integrator. The VCSQ consists of a LinearTransconductor(LTC) and a currentmode squarer. A current source (dependent on MOS transconductance which is in turn dependent on absolute temperature) is used to bias the currentmode squarer; this provides temperature compensation of the circuit. The circuit is simulated for AMI05 (0.5um) technology using Eldo in Mentor Graphics environment. With the compensation, the VCSQ output drift with temperature is achieved better than 1.98% in the 10~90°C range for ±1.2V input range. The integrator output drift is achieved for full scale error better than 2.5% in the 1090°C range, 1.6% in the 30~90°C range. © Copyright 2011 IEEE – All Rights Reserved
20110320T00:13:18Z
Lu, Chengbin; Postula, Adam

A CMOS switched capacitor implementation of the MihalasNiebur neuron
http://espace.library.uq.edu.au/view/UQ:316186
20131127T10:24:55Z
Folowosele, Fopefolu; EtienneCummings, Ralph; Hamilton, Tara Julia

A cognitive genetic algorithm for power distribution system planning
http://espace.library.uq.edu.au/view/UQ:77101
Power systems are large scale nonlinear systems with high complexity. Various optimization techniques and expert systems have been used in power system planning. However, there are always some factors that cannot be quantified, modeled, or even expressed by expert systems. Moreover, such planning problems are often large scale optimization problems. Although computational algorithms that are capable of handling large dimensional problems can be used, the computational costs are still very high. To solve these problems, in this paper, investigation is made to explore the efficiency and effectiveness of combining mathematic algorithms with human intelligence. It had been discovered that humans can join the decision making progresses by cognitive feedback. Based on cognitive feedback and genetic algorithm, a new algorithm called cognitive genetic algorithm is presented. This algorithm can clarify and extract human's cognition. As an important application of this cognitive genetic algorithm, a practical decision method for power distribution system planning is proposed. By using this decision method, the optimal results that satisfy human expertise can be obtained and the limitations of human experts can be minimized in the mean time.
20070815T06:53:37Z
Duan, Gang; Yu, Yixin; Dong, Zhao Yang

A Collaborative Digestion and Design Game for Community and Technology Exploration
http://espace.library.uq.edu.au/view/UQ:103320
20070823T21:30:20Z
Viller, S. A.; Brereton, M. F.; Redhead, F. S.; Axup, J.

A collaborative scholarly annotation system for dynamic web documents  A literary case study
http://espace.library.uq.edu.au/view/UQ:208086
This paper describes ongoing work within the AuseLit project at the University of Queensland to provide collaborative annotation tools for Australian Literary Scholars. It describes our implementation of an annotation framework to facilitate collaboration and sharing of annotations within research subcommunities. Using the annotation system, scholars can collaboratively select web resources and attach different types of annotations (comments, notes, queries, tags and metadata), which can be harvested to enrich the AustLit collection. We describe how rich semantic descriptions can be added to the constantly changing AustLit collection through a set of interoperable annotation tools based on the Open Annotations Collaboration (OAC) model. RDFa enables scholars to semantically annotate dynamic web pages and contribute typed metadata about the IFLA FRBR entities represented within the AustLit collection. We also describe how the OAC model can be used in combination with OAIORE to produce scholarly digital editions, and compare this approach with existing scholarly annotation approaches. © 2010 SpringerVerlag.
20100718T00:09:55Z
Gerber, Anna; Hyland, Andrew; Hunter, Jane

A combined approach for information flow analysis in fault tolerant hardware
http://espace.library.uq.edu.au/view/UQ:137754
Fault tolerance in information security devices is difficult to establish due to the large number of possible interactions in the device (e. g. embedded code, boolean logic, electromagnetic interference, etc.) In previous work we examined information flow as a graph problem by composing orthogonal views of the device under analysis. In other work we used faulttree analysis to reason about information flow as a systemic failure arising from certain configurations (or faults) in either the control logic or data flow 'backbone'. In this paper we combine these approaches by taking advantage of an alternative representation of fault trees as reliability block diagrams.
20080507T11:51:36Z
McComb, T.; Wildman, L.

A combined approach to checking web ontologies
http://espace.library.uq.edu.au/view/UQ:161764
The understanding of Semantic Web documents is built upon ontologies that define concepts and relationships of data. Hence, the correctness of ontologies is vital. Ontology reasoners such as RACER and FaCT have been developed to reason ontologies with a high degree of automation. However, complex ontologyrelated properties may not be expressible within the current web ontology languages, consequently they may not be checkable by RACER and FaCT. We propose to use the software engineering techniques and tools, i.e., Z/EVES and Alloy Analyzer, to complement the ontology tools for checking Semantic Web documents. In this approach, Z/EVES is first applied to remove trivial syntax and type errors of the ontologies. Next, RACER is used to identify any ontological inconsistencies, whose origins can be traced by Alloy Analyzer. Finally Z/EVES is used again to express complex ontologyrelated properties and reveal errors beyond the modeling capabilities of the current web ontology languages. We have successfully applied this approach to checking a set of military plan ontologies
20090127T11:41:37Z
Dong, J S; Lee, C H; Lee, H B; Li, YF

A combined practical approach for distribution system loss reduction
http://espace.library.uq.edu.au/view/UQ:311531
20131003T16:15:57Z
Duong, Quoc Hung; Nadarajah, M.; Bansal, R. C.

A combined voxel and surface based method for topology correction of brain surfaces
http://espace.library.uq.edu.au/view/UQ:246050
Brain surfaces provide a reliable representation for cortical mapping. The construction of correct surfaces from magnetic resonance images (MRI) segmentation is a challenging task, especially when genus zero surfaces are required for further processing such as parameterization, partial inflation and registration. The generation of such surfaces has been approached either by correcting a binary image as part of the segmentation pipeline or by modifying the mesh representing the surface. During this task, the preservation of the structure may be compromised because of the convoluted nature of the brain and noisy/imperfect segmentations. In this paper, we propose a combined, voxel and surfacebased, topology correction method which preserves the structure of the brain while yielding genus zero surfaces. The topology of the binary segmentation is first corrected using a set of topology preserving operators applied sequentially. This results in a white matter/gray matter binary set with correct sulci delineation, homotopic to a filled sphere. Using the corrected segmentation, a marching cubes mesh is then generated and the tunnels and handles resulting from the meshing are finally removed with an algorithm based on the detection of nonseparating loops. The approach was validated using 20 young individuals MRI from the OASIS database, acquired at two different timepoints. Reproducibility and robustness were evaluated using global and local criteria such as surface area, curvature and point to point distance. Results demonstrated the method capability to produce genus zero meshes while preserving geometry, two fundamental properties for reliable and accurate cortical mapping and further clinical studies.
20110822T18:33:58Z
Gris, Florence; Favreau, JeanMarie; Acosta, Oscar; Barra, Vincent; Salvado, Olivier

A compact and broadband NRITL metamaterial monopole antenna
http://espace.library.uq.edu.au/view/UQ:262777
A compact and broadband negativerefractiveindex transmissionline (NRITL) metamaterial antenna is proposed, which consists of a conventional printed monopole loaded in a lefthanded fashion. The metamaterial loading allows the antenna to be modeled as a short folded monopole around 5.5 GHz, and simultaneously acts as a a balun for the ground plane around 3.55 GHz, therefore enabling the ground plane to radiate at this frequency. Consequently, the metamaterialloaded monopole antenna exhibits a very wide impedance bandwidth by virtue of the orthogonality between these two radiating modes. The NRITL metamaterial monopole antenna has a simulated 10 dB returnloss bandwidth of 3.84 GHz while maintaining a very high efficiency in the order of 90%, and achieves orthogonal pattern diversity in both the 3.3  3.8 GHz WiMax and 5.15  5.85 GHz WiFi bands.
20111202T16:39:43Z
Antoniades, Marco A.; Eleftheriades, George V.

A compact and directive UWB antenna for biomedical applications
http://espace.library.uq.edu.au/view/UQ:136900
20080430T16:37:49Z
Abbosh, A.; Bialkowski, M.E.

A compact and lowprofile metamaterial ring antenna with vertical polarization
http://espace.library.uq.edu.au/view/UQ:262761
20111202T16:04:42Z
Qureshi, F.; Antoniades, M. A.; Eleftheriades, G. V.

A Compact Argumentation System for Agent System Specification
http://espace.library.uq.edu.au/view/UQ:8198
We present a nonmonotonic logic tailored for specifying compact autonomous agent systems. The language is a consistent instantiation of a logic based argumentation system extended with Brooks' subsumption concept and varying degree of belief. Particularly, we present a practical implementation of the language by developing a metaencoding method that translates logical specifications into compact general logic programs. The language allows nary predicate literals with the usual firstorder term definitions. We show that the space complexity of the resulting general logic program is linear to the size of the original theory.
20060630T00:00:00Z
Song, I.; Governatori, G.

A compact crossover using NRITL metamaterial lines
http://espace.library.uq.edu.au/view/UQ:284879
A compact NRITL metamaterial branchline crossover is presented that has an area of λ/36 × λ/12, and is a factor of 81 times smaller than its analogous transmissionline counterpart. Circuit simulations reveal that it exhibits a 34% −10 dB S11 bandwidth, good isolation below −10 dB over a 22% bandwidth, and less than 0.5 dB insertion loss over a 15% bandwidth. Furthermore, the bandwidth of the device can be increased by incorporating additional branchline sections into the structure.
20121114T18:42:23Z
Antoniades, Marco A.; Henin, Bassem; Abbosh, Amin

A compact heptaband antenna for portable and embedded devices
http://espace.library.uq.edu.au/view/UQ:273943
The article presents the design of a compact heptaband antenna for portable and embedded applications targeting the GSM900/DCS/PCS/UMTS2100 cellular and 2.4/5.2/5.5GHz WLAN bands. A printed invertedF antenna with a folded primary arm and a second radiating arm on the bottom surface of the substrate initially provides triband operation in the 900, 1700, and 2450MHz bands. The shortingarm is relocated below the primary arm for a reduction in occupied area. The addition of a long slot in the ground plane offers an additional operation around 2100 MHz, bridging the 1700 and 2450MHz resonances and promoting significantly wideband performance of more than 900 MHz in that band. A second ground slot allows the antenna to support two of the 5GHz WLAN bands. Laboratory measurements confirm the performance of the final heptaband antenna, with 6dB return loss met from 880–1000, 1680–2590, and 5150–5710 MHz, and better than 10dB return loss at the centers and edges of these bands.
20120514T21:23:10Z
Boldaji, Ashkan; Bialkowski, Marek E.

A compact laser imaging system for concurrent reflectance confocal microscopy and laser doppler flowmetry
http://espace.library.uq.edu.au/view/UQ:399542
We propose a compact laser feedback interferometry imaging system for concurrent reflectance confocal microscopy and laser Doppler flowmetry. This system acquires both confocal reflectance and Doppler signals in a confocal architecture to image dynamic turbid media with higher contrast than a system operating in either modality, and is coherent in nature. In a confocal optical configuration, reflectance confocal microscopy provides information about scattering from within a small volume centered around the focal point of the confocal system, and laser Doppler flowmetry provides information about the velocity of moving scatterers within the same volume. Raster scanning the sample enables the concurrent creation of two images, containing independent information, from a well specified depth within the sample. Concurrent spatial mapping of these independent sensing modalities affords improvement in the capability of the imaging system by obtaining additional information from both morphological and functional features of the dynamic turbid medium, at depths penetrable by nearinfrared lasers. We realize the idea using a laser feedback interferometry imaging system scanning a microfluidic channel which contains a dynamic turbid medium. We show the effectiveness of this integrated imager quantitatively through the improvement of the signal to background ratio of a combined (multiplication) image.
20160811T11:59:45Z
Mowla, Alireza; Taimre, Thomas; Lim, Yah Leng; Bertling, Karl; Wilson, Stephen J.; Prow, Tarl W.; Rakic, Aleksandar D.

A compact lowprofile highimpedance surface for use as an antenna ground plane
http://espace.library.uq.edu.au/view/UQ:262773
A compact and lowprofile highimpedance surface is proposed which offers a significantly smaller footprint without affecting the usable reflection phase bandwidth of the structure. The unit cell of the proposed surface is similar to the traditional `mushroom' structure, but utilizes interdigitatedcapacitor and spiralinductor lumped elements to reduce its size without sacrificing the inphase reflection bandwidth. It is determined that the reflectionphase resonance and bandwidth is largely independent of the shunt inductive loading and depends primarily on the value of the series capacitive loading. Finally, an application of the structure as a highimpedance ground plane for a printed loop antenna is proposed.
20111202T16:29:06Z
Raza, Shahzad; Antoniades, Marco A.; Eleftheriades, George V.

A compact monopole antenna with a defected ground plane for multiband applications
http://espace.library.uq.edu.au/view/UQ:262757
The primary interest of this work is to create a multiband antenna that can be used for various wireless LAN standards (e.g. WiFi, WiMax), while occupying a small area. It will be shown that this can be achieved by etching an Lshaped slot in the ground plane of a UWB grounded monopole antenna. The resulting "defected ground plane" creates an additional two resonances in the input impedance of the antenna, whose locations can be adjusted according to the size and location of the slot. The design is completely uniplanar, it is very low profile, and it does not require the use of any vias or lumpedelement components. It is therefore easy to fabricate using standard photolithographic procedures at a very reasonable cost, thus making it ideal for use in wireless LAN devices.
20111202T15:53:02Z
Antoniades, Marco A.; Eleftheriades, George V.

A compact multiband monopole antenna with a defected ground plane
http://espace.library.uq.edu.au/view/UQ:262767
20111202T16:18:36Z
Antoniades, M. A.; Eleftheriades, G. V.

A compact multiband NRITL metamaterialloaded planar antenna for heart failure monitoring
http://espace.library.uq.edu.au/view/UQ:324674
A compact, planar antenna is proposed, which uses negativerefractiveindex transmissionline (NRITL) metamaterial loading in order to achieve multiband operation with orthogonal pattern diversity in different bands. The antenna occupies a small footprint, which is a key requirement for its future use in a heart failure monitoring system. It is shown that by employing two metamaterial unit cells as the main radiators, this produces a dipolar mode at 1.43 GHz and 1.92 GHz and an orthogonal folded monopole mode at 4.18 GHz. The associated 10 dB bandwidths around each of these frequencies are 24 MHz, 57 MHz and 372 MHz, while the corresponding gain and radiation efficiency are 0.82 dBi (71%), 1.27 dBi (75%) and 2.13 dBi (90%), respectively. The total size of the antenna is 30 × 36 × 1.59 mm3, while the height of each radiating arm is only 5 mm.
20140304T01:59:11Z
Antoniades, Marco A.; Abbosh, Amin; Razali, Ahmad R.

A compact superconducting magnet for magnetic resonance microscopy
http://espace.library.uq.edu.au/view/UQ:35005
Magnetic resonance microscopy (MRM) depends on the use of high field, superconducting magnet systems for its operation. The magnets that are conventionally used are those that were initially designed for chemical structural analysis work. A novel, compact magnet designed specifically for MRM is presented here, and while preserving high field, high homogeneity conditions, has a length less than onethird that of conventional systems. This enables much better access to samples, an important consideration in many MRM experiments. As the homogeneity of a magnet is strongly dependent on its length, novel geometries and optimization techniques are required to meet the requirements of MRM in a compact system. An important outcome of the stochastic optimization performed in this work, is that the use used of a thin superconducting solenoid surrounded by counterwound disk windings provides a mechanism for drastic length reductions over conventional magnet designs. (C) 1998 American Institute of Physics.
20070813T10:33:10Z
Crozier, S; Doddrell, DM

A compact switchedbeam array antenna for mobile satellite communications
http://espace.library.uq.edu.au/view/UQ:144516
This paper presents the design and development of a compact switchedbeam array antenna for operation with the Australian mobile satellite communications system. Mobilesat(TM). The antenna is formed by eight aperturecoupled microstrip patch elements that are positioned on the side of a truncated comb Two elements, facing the satellite, are activated using an eightway twoportson radial switch. The output ports of the radial switch incorporate 1bit phase shifters A total of 24 beams are produced using this beamforming system. lit order to reduce the manufacturing cost, inexpensive substrates and lowcost UHF pin diodes are employed Further reduction in cast is achieved by eliminating coaxial connectors between the beamforming network and the antenna elements. Experimental results are presented for the individual antenna elements, the beamforming network, and the entire switchedbeam array. (C) 1999 John Wiley & Sons, Inc.
20080610T15:12:25Z
Karmakar, N. C.; Bialkowski, M. E.

A Compact TriBand Monopole Antenna With SingleCell Metamaterial Loading
http://espace.library.uq.edu.au/view/UQ:262771
20111202T16:22:27Z
Zhu, J.; Antoniades, M. A.; Eleftheriades, G. V.

A compact UWB threeway power divider
http://espace.library.uq.edu.au/view/UQ:129602
A threeway power divider with ultra wideband behavior is presented. It has a compact size with an overall dimension of 20 mm * 30 mm. The proposed divider utilizes broadside coupling via multilayer microstrip/slot transitions of elliptical shape. The simulated and measured results show that the proposed device has 4.77 +/ 1dB insertion loss, better than 17 dB return loss, and better than 15 dB isolation across the frequency band 3.1 to 10.6 GHz.
20080218T14:36:24Z
Abbosh, A.M.

A Comparative Evaluation of Action Recognition Methods via Riemannian Manifolds, Fisher Vectors and GMMs: Ideal and Challenging Conditions
http://espace.library.uq.edu.au/view/UQ:387614
We present a comparative evaluation of various techniques for action recognition while keeping as many variables as possible controlled. We employ two categories of Riemannian manifolds: symmetric positive definite matrices and linear subspaces. For both categories we use their corresponding nearest neighbour classifiers, kernels, and recent kernelised sparse representations. We compare against traditional action recognition techniques based on Gaussian mixture models and Fisher vectors (FVs). We evaluate these action recognition techniques under ideal conditions, as well as their sensitivity in more challenging conditions (variations in scale and translation). Despite recent advancements for handling manifolds, manifold based techniques obtain the lowest performance and their kernel representations are more unstable in the presence of challenging conditions. The FV approach obtains the highest accuracy under ideal conditions. Moreover, FV best deals with moderate scale and translation changes.
20160527T14:41:28Z
Carvajal, Johanna; Wiliem, Arnold; McCool, Chris; Lovell, Brian C.

A comparative numerical study of rotating and stationary RF coils in terms of flip angle and specific absorption rate for 7 T MRI
http://espace.library.uq.edu.au/view/UQ:312800
20131022T17:23:19Z
Trakic, A.; Jin, J.; Li, M.; McClymont, D.; Weber, E.; Liu, F.; Crozier, S.

A comparative study of modulation scheme for threephase voltage inverter
http://espace.library.uq.edu.au/view/UQ:216830
20100921T18:34:40Z
Mishra, Ambarisha; Joshi, Dheeraj; Bansal, R. C.

A comparative study of modulation scheme for threephase voltage source inverter
http://espace.library.uq.edu.au/view/UQ:233283
20110308T16:51:34Z
Mishra, Ambarisha; Joshi, Dheeraj; Bansal, R. C.

A Comparative Study of the Dielectric Strength of Ester Impregnated Cellulose for Use in Large Power Transformers
http://espace.library.uq.edu.au/view/UQ:309783
20130920T09:43:16Z
Martin, D.; Wang, Z. D.; Dyer, P.; Darwin, A. W.; James, I.

A comparative study on signal processing for partial discharge measurement
http://espace.library.uq.edu.au/view/UQ:353635
20150311T14:34:20Z
Chan, Jeffery; Ma, Hui; Saha, Tapan

A comparison of DCT and DWT block based watermarking on medical image quality
http://espace.library.uq.edu.au/view/UQ:249617
Hiding watermark information in medical image data files is one method of enhancing security and protecting patient privacy. However the research area of medical image watermarking has not been particularly active, partly due to concerns that any distortion could affect the diagnostic value of the medical image. These concerns can be addressed by ensuring that any image changes are kept below visual perception thresholds. In this paper the effects of image watermarking and common image manipulations are measured using the Peak SignaltoNoise Ratio (PSNR), Structural Similarity Measure (SSIM) and Steerable Visual Difference Predictor (SVDP) numerical metrics. Two methods of block based watermarking are compared: the Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT). To ensure a fair comparison a 128pixel block size is used which allows an identical amount of information to be embedded for each method (3072 bits multiplied by embedding strength). The results suggest that although the two methods are similar, the DCT method is preferable if localization of changes is required. If localization is not required the DWT method is supported.
20110910T02:06:01Z
Dowling, Jason; Planitz, Birgit M.; Maeder, Anthony J.; Du, Jiang; Pham, Binh; Boyd, Colin; Chen, Shaokang; Bradley, Andrew P.; Crozier, Stuart

A comparison of different choices for the regularization parameter in inverse electrocardiography models
http://espace.library.uq.edu.au/view/UQ:104274
Calculating the potentials on the heart’s epicardial surface from the body surface potentials constitutes one form of inverse problems in electrocardiography (ECG). Since these problems are illposed, one approach is to use zeroorder Tikhonov regularization, where the squared norms of both the residual and the solution are minimized, with a relative weight determined by the regularization parameter. In this paper, we used three different methods to choose the regularization parameter in the inverse solutions of ECG. The three methods include the Lcurve, the generalized cross validation (GCV) and the discrepancy principle (DP). Among them, the GCV method has received less attention in solutions to ECG inverse problems than the other methods. Since the DP approach needs knowledge of norm of noises, we used a model function to estimate the noise. The performance of various methods was compared using a concentric sphere model and a real geometry hearttorso model with a distribution of current dipoles placed inside the heart model as the source. Gaussian measurement noises were added to the body surface potentials. The results show that the three methods all produce good inverse solutions with little noise; but, as the noise increases, the DP approach produces better results than the Lcurve and GCV methods, particularly in the real geometry model. Both the GCV and Lcurve methods perform well in low to medium noise situations.
20070823T22:13:08Z
Shou, G F; Feng, M; Xia,; Wei, Q.; Liu, F; Crozier, S

A comparison of Gumbel and Weibull statistical models to estimate wind speed for wind power generation
http://espace.library.uq.edu.au/view/UQ:341016
Wind energy is becoming more common, especially as costs are falling. In Australia's National Electricity Market, the total available generation is managed by the Australian Energy Market Operator (AEMO). One of its tasks is to forecast the availability of generation twenty four months into the future, to ensure that the predicted customer load requirements are met. A challenge, however, is to accurately forecast the contribution of wind energy to the market on this time frame. Since the energy of wind is a function of its speed, it is common to use climate data to estimate the wind speed into the future using statistical distributions. In this analysis measurements on power generation from a South Australian wind farm and on wind speed from a weather station were compared. Statistical techniques were applied to monthly data samples. The power generated from a wind turbine is generally highest at the tail end of the wind speed distribution. Thus, the accuracy of two distributions to model wind speed, the Weibull and the Gumbel, was investigated to see which gave better fits. The Gumbel distribution was found to estimate wind speed more accurately than the Weibull model, not only at the tail end of the distribution, but also at lower levels.
20141002T16:43:57Z
Martin, D.; Zhang, W.; Chan, J.; Lindley, J.

A comparison of interval methods in symbolic circuit analysis applications
http://espace.library.uq.edu.au/view/UQ:317343
Symbolic circuit analysis involves deriving symbolic expressions for performance measures, such as voltage gain, input impedance, and evaluating them to obtain more insight into the behaviour of a circuit. In modern semiconductor technologies, it is more useful to evaluate the symbolic expressions using interval methods in order handle variations in parameter values. We compare the performance of different interval methods in evaluating symbolic expressions. Our experiments show that Generalised Interval Arithmetic is the most efficient method in affne form for our application. However, this method should be modified to suit long chains of computation. Our modification yields tighter interval bounds compared with other interval methods.
20131128T10:20:19Z
Thanigaivelan, Balavelan; Hamilton, Tara Julia; Postula, Adam

A comparison of multiple instance and group based learning
http://espace.library.uq.edu.au/view/UQ:295625
In this paper we compare the performance of a number of multipleinstance learning (MIL) and group based (GB) classification algorithms on both a synthetic and realworld Pap smear dataset. We utilise the synthetic dataset to demonstrate that performance improves as both bag size and percent positives increase and that MIL outperforms GB algorithms when the percentage positives is less than 50%. However, as the positive bags become increasingly homogeneous, as is apparent on the realworld dataset, the two approaches become comparable. This result highlights that the performance of a MIL or GB algorithm will be maximised when the algorithm's MIL assumption matches the reality of the dataset. Therefore, on the Pap smear dataset, algorithms with a more generalised MIL assumption demonstrate the strongest performance.
20130403T14:23:52Z
Brossi, Steven D.; Bradley, Andrew P.

A comparison of neural landscapes: NK, NKp and NKq
http://espace.library.uq.edu.au/view/UQ:97593
20070824T01:23:26Z
Geard, N. L.; Wiles, J. H.; Hallinan, J. S.; Tonkes, B.; Skellett, B.

A comparison of neural network and fast fourier transfornbased approach for the state analysis of brain
http://espace.library.uq.edu.au/view/UQ:103085
20070823T21:21:10Z
Emoto, T.; Akutagawa, M.; Abeyratne, U. R.; Nagashino, H.; Kinouchi, Y.

A comparison of sceptical NAFfree logic programming approaches
http://espace.library.uq.edu.au/view/UQ:9622
Recently there has been increased interest in logic programmingbased default reasoning approaches which are not using negationasfailure in their object language. Instead, default reasoning is modelled by rules and a priority relation among them. Historically the first logic in this class was Defeasible Logic. In this paper we will study its relationship to other approaches which also rely on the idea of using logic rules and priorities. In particular we will study sceptical LPwNF, courteous logic programs, and priority logic.
20050407T00:00:00Z
Antoniou, Grigoris; Maher, Michael J.; Billington, David; Governatori, Guido

A comparison of schemas for video metadata representation
http://espace.library.uq.edu.au/view/UQ:7838
20061005T00:00:00Z
Hunter, Jane; Armstrong, Liz

A comparison of sequence kernels for localization prediction of transmembrane proteins
http://espace.library.uq.edu.au/view/UQ:136214
We applied support vector machines to the prediction of the subcellular localization of transmembrane proteins, and compared the performance of different sequence kernels on this task. More specifically we measured prediction accuracy, computation time, number of kernel evaluations and number of support vectors for the spectrum, the full spectrum, the wildcard, the mismatch, the localalignment and the residuecoupling kernel. The localalignment achieved the highest prediction accuracy, with a Matthews correlation coefficient of 0.51, closely followed by the mismatch kernel. However, the localalignment kernel was also the most time consuming kernel and seven times slower than the mismatch kernel. The spectrum kernel was the fastest kernel but linked to the highest number of support vectors and kernel evaluations. The residuecoupling kernel showed the lowest number of support vectors and kernel evaluations. No correlation between the number of support vectors and prediction accuracy could be observed. A localization predictor (TMPLoc) has been made available at http://pprowler.itee.uq.edu.au/TMPLoc
20080424T09:47:33Z
Maetschke, S.; Gallagher, M.; Boden, M.

A Comparison of Small Signal Modulation Parameter Extraction Techniques for VerticalCavity, SurfaceEmitting Lasers
http://espace.library.uq.edu.au/view/UQ:8600
The small signal modulation characteristics of a verticalcavity, surfaceemitting laser (VCSEL) are determined using three different measurements: relative intensity noise, frequency response, and high resolution optical spectra. The resonant and damping frequencies were measured, and related rate equation parameters were extracted; excellent agreement was found both between experiment and theory, and amongst the different measurement techniques. The results and procedures are compared, and the findings are presented below.
20060221T00:00:00Z
O'Brien, Christopher J.; Majewski, M. L.; Rakic, A. D.

A Comparison of Some Fuzzy Relationbased Linguistic Preference Models for MultipleFactor Project Assessment
http://espace.library.uq.edu.au/view/UQ:7766
Some approaches to the use of linguisticpreference models based on fuzzy relations in the context of multiple factor project assessment are considered. Projects are characterized in terms of linguistic expressions of 'performance' with respect to factors or impacts and the 'importance' of those factors and impacts. Some variations of methods by Wilhelm and Parsaei (1991) and Eldukair and Ayyub (1992) are considered with some possible analogous methods. A simple illustrative, hypothetical example is developed to compare methods in the context of a proposed bridge river crossing in the city of Brisbane, Queensland, Australia, assessed against six factors: (1) cost, (2) lifespan, (3) usage, (4) aesthetics, (5) construction time, and (6) environmental impact.
20061122T00:00:00Z
Smith, Phillip

A Comparison of the Formation of Bubbles and Water Droplets in Vegetable and Mineral Oil Impregnated Transformer Paper
http://espace.library.uq.edu.au/view/UQ:343422
20141025T11:15:50Z
Perkasa, Caesar Y.; Lelekakis, Nick; Czaszejko, Tadeusz; Wijaya, Jaury; Martin, Daniel

A comparison of two iterations of a software studio course based on continuous integration
http://espace.library.uq.edu.au/view/UQ:317776
20131128T18:02:58Z
Billingsley, William; Steel, Jim

A comparison of ultracapacitor, BESS and shunt capacitor on oscillation damping of power system with largescale PV plants
http://espace.library.uq.edu.au/view/UQ:256017
Intermittent and slow generator like PV is augmented with auxiliary device to meet the certain grid code requirements for interconnection. Ultracapacitor, battery energy storage system (BESS) or shunt capacitor at the PV terminal have recently been used as auxiliary devices for largescale PV generator system to improve the system performance during transients. Although the studies on individual auxiliary devices are well documented, a comparative study of these devices impact on the damping of electromechanical (EM) mode and oscillatory instability problem has not been reported so far. This paper presents the damping performance of largescale PV with auxiliary devices. The simulation studies have been done on multimachine infinite bus (MMIB) system and twoarea test system. For simulation studies different types of synchronous generators (e.g. hydro, thermal) are also taken into consideration.
20111014T12:46:43Z
Shah, Rakibuzzaman; Mithulananthan, N.

A comparison study of different RF shields for an 8element transceive small animal array at 9.4T
http://espace.library.uq.edu.au/view/UQ:263810
In this study, three types of radiofrequency shields are studied and compared in the context of ultrahigh field smallanimal magnetic resonance imaging. It has been demonstrated that the coil penetration depth and mutual coupling between the coils depend heavily on the type of shield employed. The results were used to guide the design of a 9.4T 8element transceive small animal array, which provides high overall coil penetration.
20111220T10:38:38Z
Jin, Jin; Li, Yu; Liu, Feng; Weber, Ewald; Crozier, Stuart

A comparison study of regularization techniques on the theoretical design of phased array RF coils in MRI
http://espace.library.uq.edu.au/view/UQ:175820
In MRI engineering, regularization techniques can be effectively used to solve illposed problems in electromagnetics, such as the inverse design of phased array RF coils. In this work, a comparison on various regularization methods which are employed to numerically reconstruct a divergencefree cylindrical surface of current distribution is investigated. It is found that a coil current pattern is very sensitive to the modes of the basis function describing the current densities on the coil surface; and iterative regularization techniques generally produce better B1 field profiles compared with direct approaches.
20090415T11:34:14Z
Li, Y.; Wang, H.; Liu, F.; Li, B.K.; Shou, G.; Weber, E.; Crozier, S.