• Prediction of self-compacting concrete elastic modulus using two symbolic regression techniques

      Golafshani, E.M.; Ashour, Ashraf F. (2016)
      This paper introduces a novel symbolic regression approach, namely biogeographical-based programming (BBP), for the prediction of elastic modulus of self-compacting concrete (SCC). The BBP model was constructed directly from a comprehensive dataset of experimental results of SCC available in the literature. For comparison purposes, another new symbolic regression model, namely artificial bee colony programming (ABCP), was also developed. Furthermore, several available formulas for predicting the elastic modulus of SCC were assessed using the collected database. The results show that the proposed BBP model provides slightly closer results to experiments than ABCP model and existing available formulas. A sensitivity analysis of BBP parameters also shows that the prediction by BBP model improves with the increase of habitat size, colony size and maximum tree depth. In addition, among all considered empirical and design code equations, Leemann and Hoffmann and ACI 318-08’s equations exhibit a reasonable performance but Persson and Felekoglu et al.’s equations are highly inaccurate for the prediction of SCC elastic modulus.
    • Prediction of Solar Activity from Solar Background Magnetic Field Variations in Cycles 21-23

      Shepherd, Simon J.; Zharkov, S.I.; Zharkova, Valentina V. (2014)
      A comprehensive spectral analysis of both the solar background magnetic field (SBMF) in cycles 21-23 and the sunspot magnetic field in cycle 23 reported in our recent paper showed the presence of two principal components (PCs) of SBMF having opposite polarity, e. g., originating in the northern and southern hemispheres, respectively. Over a duration of one solar cycle, both waves are found to travel with an increasing phase shift toward the northern hemisphere in odd cycles 21 and 23 and to the southern hemisphere in even cycle 22. These waves were linked to solar dynamo waves assumed to form in different layers of the solar interior. In this paper, for the first time, the PCs of SBMF in cycles 21-23 are analyzed with the symbolic regression technique using Hamiltonian principles, allowing us to uncover the underlying mathematical laws governing these complex waves in the SBMF presented by PCs and to extrapolate these PCs to cycles 24-26. The PCs predicted for cycle 24 very closely fit (with an accuracy better than 98%) the PCs derived from the SBMF observations in this cycle. This approach also predicts a strong reduction of the SBMF in cycles 25 and 26 and, thus, a reduction of the resulting solar activity. This decrease is accompanied by an increasing phase shift between the two predicted PCs (magnetic waves) in cycle 25 leading to their full separation into the opposite hemispheres in cycle 26. The variations of the modulus summary of the two PCs in SBMF reveals a remarkable resemblance to the average number of sunspots in cycles 21-24 and to predictions of reduced sunspot numbers compared to cycle 24: 80% in cycle 25 and 40% in cycle 26.
    • Prediction of the depth-averaged two-dimensional flow direction along a meander in compound channels

      Shan, Y.; Huang, S.; Liu, C.; Guo, Yakun; Yang, K. (2018-10)
      For overbank flows in meandering channels, the flow direction along a meander varies and is affected by floodplain vegetation. This study proposes a model for predicting the depth-averaged two-dimensional flow direction (depth-averaged flow angle) along a meander in smooth and vegetated meandering compound channels. Laboratory experiments were performed in smooth and vegetated channels. Measurements show that the height of the secondary current cell in the main channel is increased by dense floodplain vegetation comparing with that in a non-vegetated channel. A method of determining the height of the cell is proposed. At the middle section between the apex and exit sections, where the secondary current cell is absent, the depth-averaged flow angle is independent of the height of the cell. Beyond the middle section, a new secondary current cell is formed, and the flow angle is highly dependent on the height of the cell. The proposed model is thoroughly verified using the flume experimental and field observed data. Good agreement is obtained between predictions and measurements, indicating that the proposed model is capable of accurately predicting the depth-averaged flow angle along a meander in smooth and vegetated meandering compound channels.
    • Prediction of the effect of formulation on the toxicity of chemicals

      Mistry, Pritesh; Neagu, Daniel; Sanchez-Ruiz, A.; Trundle, Paul R.; Vessey, J.D.; Gosling, J.P. (2017)
      Two approaches for the prediction of which of two vehicles will result in lower toxicity for anticancer agents are presented. Machine-learning models are developed using decision tree, random forest and partial least squares methodologies and statistical evidence is presented to demonstrate that they represent valid models. Separately, a clustering method is presented that allows the ordering of vehicles by the toxicity they show for chemically-related compounds.
    • Predictive Control Strategy for Temperature Control for Milk Pasteurization Process

      Niamsuwan, S.; Kittisupakorn, P.; Mujtaba, Iqbal M. (2013)
      A milk pasteurization process is a nonlinear process and multivariable interacting system. This makes it difficultly to control by the conventional on-off controllers. Even if the on-off controller can managed the milk temperatures in the holding tube and the cooling stage of the plate pasteurizer according to the plant's requirements, the dynamic profiles of the milk temperature are oscillating around a desired value. Consequently, this work is aimed at improving the control performance by a multi-variables control approach with model predictive control (MPC). The proposed algorithm was tested in the case of set point tracking under nominal condition gathered by the real observation. To compare the performance of the MPC controller, a model-based control approach of generic model control (GMC) coupled with cascade control strategy is taken into account. The simulation results demonstrated that a proposed control algorithm performed well in keeping both the milk and water temperatures at the desired set points without any oscillation and overshoot. Because of the predictive control strategy, the control response for MPC was less drastic control action compared to the GMC.
    • Prehension of a flanked target in individuals with amblyopia.

      Buckley, John G.; Pacey, Ian E.; Scally, Andy J.; Barrett, Brendan T.; Panesar, Gurvinder K. (2015-11)
      Purpose: Reduced binocularity is a prominent feature of amblyopia and binocular cues are thought to be important for prehension. We examine prehension in individuals with amblyopia when the target-object was flanked, thus mimicking everyday prehension. Methods: amblyopes (n=20, 36.4±11.7 years; 6 anisometropic, 3 strabismic, 11 mixed) and visually-normal controls (n=20, 27.5±6.3 years) reached forward, grasped and lifted a cylindrical target-object that was flanked with objects on either (lateral) side of the target, or in front and behind it in depth. Only 6 amblyopes (30%) had measurable stereoacuity. Trials were completed in binocular and monocular viewing, using the better eye in amblyopic participants. Results: Compared to visual normals, amblyopes displayed a longer overall movement time (p=0.031), lower average reach velocity (p=0.021), smaller maximum aperture (p=0.007) and longer durations between object contact and lift (p=0.003). Differences between groups were more apparent when the flankers were in front and behind, compared to either side, as evidenced by significant group-by-flanker configuration interactions for reach duration (p<0.001), size and timing of maximum aperture (p≤0.009), end-of-reach to object-contact (p<0.001), and between object contact and lift (p=0.044), suggesting that deficits are greatest when binocular cues are richest. Both groups demonstrated a significant binocular advantage, in that in both groups performance was worse for monocular compared to binocular viewing, but interestingly, amblyopic deficits in binocular viewing largely persisted during monocular viewing with the better eye. Conclusions: These results suggest that amblyopes either display considerable residual binocularity or that they have adapted to make good use of their abnormal binocularity.
    • A preliminary radicalisation framework based on social engineering techniques

      Sabouni, S.; Cullen, Andrea J.; Armitage, Lorna (2017-06-20)
      The use of online forums and social media sites by extremists for recruiting and radicalising individuals has been covered extensively by researchers. Meanwhile, the social engineering techniques utilised by these extremists to lure marginalised individuals into radicalisation has been neglected. In this article, the social engineering aspects of online radicalisation will be explored. Specifically, the five Principles of Persuasion in Social Engineering (PPSE) will be mapped onto the online radicalisation methods employed by extremists online. Analysing these tactics will aid in gaining a deeper understanding of the process of indoctrination and of the psychology of both the attacker and the target of such attacks. This understanding has enabled the development of a preliminary radicalisation framework based on the social traits of a target that may be exploited during an attack.
    • A preliminary study of the characteristics of noisy vehicles under cruising conditions – results of roadside measurements

      Watts, Gregory R. (2012-03)
      In the past it has been found that the maximum pass-by noise for the most noisy of vehicles can be 6-8 dB(A) above the average for the sample. It is therefore useful to consider the types of vehicle that make excessive noise and their condition and to reach some conclusions on how best to reduce the problem. Measurements of maximum noise, pass-by speed together with video footage were taken on a busy dual carriageway road (A34) in the UK carrying a high percentage of heavy vehicles. The intention was to collect sufficient information on light, medium heavy and heavy vehicles to enable typical characteristics of noisy vehicles to be identified. Peak noise levels produced by vehicles under normal operating conditions of steady speed were recorded and not of vehicle being driven in an aggressive manner e.g. under harsh acceleration. This paper reports on the characteristics of excessively noisy vehicles that were identified under these cruising conditions in free flow traffic conditions.
    • Preparation and in vivo efficient anti-infection property of GTR/GBR implant made by metronidazole loaded electrospun polycaprolactone nanofiber membrane

      Xue, J.; He, M.; Niu, Y.; Liu, H.; Crawford, A.; Coates, Philip D.; Chen, D.; Shi, R.; Zhang, L. (2014)
      Infection is the major reason of GTR/GBR membrane failure in clinical application. In this work, we developed GTR/GBR nanofiber membranes with localized drug delivery function to prevent infection. Metronidazole (MNA), an antibiotic, was successfully incorporated into electrospun polycaprolactone (PCL) nanofibers at different concentrations (0, 1, 5, 10, 20, 30, and 40 wt% polymer). To obtain the optimum anti-infection membrane, we systematically investigated the physical-chemical and mechanical properties of the nanofiber membranes with different drug contents. The interaction between PCL and MNA was identified by molecular dynamics simulation. MNA released in a controlled, sustained manner over 2 weeks and the antibacterial activity of the released MNA remained. The incorporation of MNA improved the hydrophilicity and in vitro biodegradation rate of PCL nanofibers. The nanofiber membranes allowed cells to adhere to and proliferate on them and showed excellent barrier function. The membrane loaded with 30% MNA had the best comprehensive properties. Analysis of subcutaneous implants demonstrated that MNA-loaded nanofibers evoked a less severe inflammatory response than pure PCL nanofibers. These results demonstrate the potential of MNA-loaded nanofiber membranes as GTR/GBR membrane with antibacterial and anti-inflammatory function for extensive biomedical applications.
    • Preparation of 2D sequences of corneal images for 3D model building

      Elbita, Abdulhakim M.; Qahwaji, Rami S.R.; Ipson, Stanley S.; Sharif, Mhd Saeed; Ghanchi, Faruque (2014-04)
      A confocal microscope provides a sequence of images, at incremental depths, of the various corneal layers and structures. From these, medical practioners can extract clinical information on the state of health of the patient's cornea. In this work we are addressing problems associated with capturing and processing these images including blurring, non-uniform illumination and noise, as well as the displacement of images laterally and in the anterior posterior direction caused by subject movement. The latter may cause some of the captured images to be out of sequence in terms of depth. In this paper we introduce automated algorithms for classification, reordering, registration and segmentation to solve these problems. The successful implementation of these algorithms could open the door for another interesting development, which is the 3D modelling of these sequences.
    • Pressure Variation during Interfacial Instability in the Coextrusion of Low Density Polyethylene Melts

      Martyn, Michael T.; Coates, Philip D. (2013)
      Pressure variation during the coextrusion of two low density polyethylene melts was investigated. Melt streams were delivered to a die from two separate extruders to converge in a 30 degrees degrees geometry to form a two layer extrudate. Melt flow in the confluent region and die land to the die exit was observed through side windows of a visualisation cell. Stream velocity ratio was varied by control of extruder screw speeds. Layer thickness ratios producing wave type interfacial instability were quantified for each melt coextruded on itself and for the combined melts. Stream pressures and screw speeds were monitored and analysed. Wave type interfacial instability was present during the processing of the melts at specific, repeatable, stream layer ratios. Increased melt elasticity appeared to promote this type of instability. Analysis of process data indicates little correlation between perturbations in extruder screw speeds and stream pressures. The analysis did however show covariance between the individual stream pressure perturbations. Interestingly there was significant correlation even when interfacial instability was not present. We conclude that naturally occurring variation in extruder screw speeds do not perturb stream pressures and, more importantly, natural perturbations in stream pressures do not promote interfacial instability.
    • Printed monopole antenna with tunable band-notched characteristic for use in mobile and ultra-wide band applications

      Elfergani, Issa T.; Hussaini, Abubakar S.; See, Chan H.; Abd-Alhameed, Raed A.; McEwan, Neil J.; Zhu, Shaozhen (Sharon); Rodriguez, Jonathan; Clarke, Roger W. (2015-06)
      A tunable band-notch printed monopole antenna is presented, exhibiting a wide impedance bandwidth from 1.5 to 5.5 GHz with good impedance matching (VSWR ≤ 2) and a tunable rejected frequency band from 2.38 to 3.87 GHz. The band-notching is achieved by adding an inner chorded crescent element within a driven element of a similar shape. By varying the value of the varactor which is placed between the inner and outer arcs, the desired variable rejected can be obtained. Simulated and measured results show wide impedance bandwidth with a tunable band notch, stable radiation patterns, and consistent nearly constant gain. The antenna is suitable for mobile and portable applications.
    • Probabilistic inequalities and measurements in bipartite systems

      Vourdas, Apostolos (2019-01)
      Various inequalities (Boole inequality, Chung–Erdös inequality, Frechet inequality) for Kolmogorov (classical) probabilities are considered. Quantum counterparts of these inequalities are introduced, which have an extra 'quantum correction' term, and which hold for all quantum states. When certain sufficient conditions are satisfied, the quantum correction term is zero, and the classical version of these inequalities holds for all states. But in general, the classical version of these inequalities is violated by some of the quantum states. For example in bipartite systems, classical Boole inequalities hold for all rank one (factorizable) states, and are violated by some rank two (entangled) states. A logical approach to CHSH inequalities (which are related to the Frechet inequalities), is studied in this context. It is shown that CHSH inequalities hold for all rank one (factorizable) states, and are violated by some rank two (entangled) states. The reduction of the rank of a pure state by a quantum measurement with both orthogonal and coherent projectors, is studied. Bounds for the average rank reduction are given.
    • A probabilistic method for the operation of three-phase unbalanced active distribution networks

      Mokryani, Geev; Majumdar, A.; Pal, B.C. (2016-07-01)
      This paper proposes a probabilistic multi-objective optimization method for the operation of three-phase distribution networks incorporating active network management (ANM) schemes including coordinated voltage control and adaptive power factor control. The proposed probabilistic method incorporates detailed modelling of three-phase distribution network components and considers different operational objectives. The method simultaneously minimizes the total energy losses of the lines from the point of view of distribution network operators (DNOs) and maximizes the energy generated by photovoltaic (PV) cells considering ANM schemes and network constraints. Uncertainties related to intermittent generation of PVs and load demands are modelled by probability density functions (PDFs). Monte Carlo simulation method is employed to use the generated PDFs. The problem is solved using ɛ-constraint approach and fuzzy satisfying method is used to select the best solution from the Pareto optimal set. The effectiveness of the proposed probabilistic method is demonstrated with IEEE 13- and 34- bus test feeders.
    • Probabilistic modelling of bed-load composition.

      Tait, Simon J.; Heald, J.; McEwan, I.K.; Soressen, M.; Cunningham, G.; Willetts, B.; Goring, D. (2009-06-24)
      This paper proposes that the changes which occur in composition of the bed load during the transport of mixed-grain-size sediments are largely controlled by the distributions of critical entrainment shear stress for the various size fractions. This hypothesis is examined for a unimodal sediment mixture by calculating these distributions with a discrete particle model and using them in a probabilistic calculation of bed-load composition. The estimates of bed-load composition compare favorably with observations of fractional transport rates made in a laboratory flume for the same sediment, suggesting that the hypothesis is reasonable. The analysis provides additional insight, in terms of grain mechanics, into the processes that determine bed-load composition. These insights strongly suggest that better prediction methods will result from taking account of the variation of threshold within size fractions, something that most previous studies have neglected.
    • Probability Distribution of Rician K-Factor in Urban, Suburban and Rural Areas Using Real World Captured Data

      Abd-Alhameed, Raed A.; Jones, Steven M.R.; Noras, James M.; Zhu, Shaozhen (Sharon); Ghazaany, Tahereh S.; Van Buren, T.; Wilson, J.; Suggett, T.; Marker, S. (2014-07)
      The Rician K-factor of the vehicle-to-vehicle (V2V) wireless propagation channel is estimated using a moment-based method on the envelope of measured pulse data. The measurements were carried out under vehicle-to-vehicle wireless communication channel condition with car rooftop antenna heights at one end of the link and very low antenna height at the other end. Data captured from typical urban, suburban and rural areas are analyzed and the K-factor probability density function is generated for each scenario to give an insight into the V2V channel behavior. For all three areas, the majority of K values are found to be within the range of -10 to +10 dB. The K-factor distributions are close to normal with mean values of 1.8, 2.6 and 3 dB respectively for urban, suburban and rural area.
    • Proceedings of Cyberworlds 2009

      Ugail, Hassan; Qahwaji, Rami S.R.; Earnshaw, Rae A.; Willis, P.J. (2009-11)
    • Proceedings of the 3rd International Workshop on Intelligent Exploration of Semantic Data (IESD 2014)

      Thakker, Dhaval; Schwabe, D.; Kozaki, K.; Garcia, R.; Dijshoorn, C.; Mizoguchi, R. (2014)
    • Proceedings of the Workshop on Membrane Computing, WMC 2016.

      Konur, Savas; Gheorghe, Marian (2016-08)
      This Workshop on Membrane Computing, at the Conference of Unconventional Computation and Natural Computation (UCNC), 12th July 2016, Manchester, UK, is the second event of this type after the Workshop at UCNC 2015 in Auckland, New Zealand*. Following the tradition of the 2015 Workshop the Proceedings are published as technical report. The Workshop consisted of one invited talk and six contributed presentations (three full papers and three extended abstracts) covering a broad spectrum of topics in Membrane Computing, from computational and complexity theory to formal verification, simulation and applications in robotics. All these papers – see below, but the last extended abstract, are included in this volume. The invited talk given by Rudolf Freund, “P SystemsWorking in Set Modes”, presented a general overview on basic topics in the theory of Membrane Computing as well as new developments and future research directions in this area. Radu Nicolescu in “Distributed and Parallel Dynamic Programming Algorithms Modelled on cP Systems” presented an interesting dynamic programming algorithm in a distributed and parallel setting based on P systems enriched with adequate data structure and programming concepts representation. Omar Belingheri, Antonio E. Porreca and Claudio Zandron showed in “P Systems with Hybrid Sets” that P systems with negative multiplicities of objects are less powerful than Turing machines. Artiom Alhazov, Rudolf Freund and Sergiu Ivanov presented in “Extended Spiking Neural P Systems with States” new results regading the newly introduced topic of spiking neural P systems where states are considered. “Selection Criteria for Statistical Model Checker”, by Mehmet E. Bakir and Mike Stannett, presented some early experiments in selecting adequate statistical model checkers for biological systems modelled with P systems. In “Towards Agent-Based Simulation of Kernel P Systems using FLAME and FLAME GPU”, Raluca Lefticaru, Luis F. Macías-Ramos, Ionuţ M. Niculescu, Laurenţiu Mierlă presented some of the advatages of implementing kernel P systems simulations in FLAME. Andrei G. Florea and Cătălin Buiu, in “An Efficient Implementation and Integration of a P Colony Simulator for Swarm Robotics Applications" presented an interesting and efficient implementation based on P colonies for swarms of Kilobot robots. *http://ucnc15.wordpress.fos.auckland.ac.nz/workshop-on-membrane-computingwmc- at-the-conference-on-unconventional-computation-natural-computation/
    • Process efficiency in polymer extrusion: Correlation between the energy demand and melt thermal stability

      Abeykoon, Chamil; Kelly, Adrian L.; Vera-Sorroche, Javier; Brown, Elaine C.; Coates, Philip D.; Deng, J.; Li, K.; Harkin-Jones, E.; Price, M. (2014-12-15)
      Thermal stability is of major importance in polymer extrusion, where product quality is dependent upon the level of melt homogeneity achieved by the extruder screw. Extrusion is an energy intensive process and optimisation of process energy usage while maintaining melt stability is necessary in order to produce good quality product at low unit cost. Optimisation of process energy usage is timely as world energy prices have increased rapidly over the last few years. In the first part of this study, a general discussion was made on the efficiency of an extruder. Then, an attempt was made to explore correlations between melt thermal stability and energy demand in polymer extrusion under different process settings and screw geometries. A commodity grade of polystyrene was extruded using a highly instrumented single screw extruder, equipped with energy consumption and melt temperature field measurement. Moreover, the melt viscosity of the experimental material was observed by using an off-line rheometer. Results showed that specific energy demand of the extruder (i.e. energy for processing of unit mass of polymer) decreased with increasing throughput whilst fluctuation in energy demand also reduced. However, the relationship between melt temperature and extruder throughput was found to be complex, with temperature varying with radial position across the melt flow. Moreover, the melt thermal stability deteriorated as throughput was increased, meaning that a greater efficiency was achieved at the detriment of melt consistency. Extruder screw design also had a significant effect on the relationship between energy consumption and melt consistency. Overall, the relationship between the process energy demand and thermal stability seemed to be negatively correlated and also it was shown to be highly complex in nature. Moreover, the level of process understanding achieved here can help to inform selection of equipment and setting of operating conditions to optimise both energy and thermal efficiencies in parallel.