Now showing items 1-20 of 7688

    • Governance and economics of smart cities: opportunities and challenges

      Anand, Prathivadi B.; Navio-Marco, J. (2018-11)
      This editorial introduction to this special issue provides an overview and a conceptual framework of governance and economics of smart cities. We begin with a discussion of the background to smart cities and then it focuses on the key challenges for consideration in smart city economics. Here it is argued that there are four dimensions to smart city economics: the first is regarding the scale of global market for smart cities; the second issue concerns data to be used for smart city projects; the third concerns market competition and structure and the fourth concerns the impact on local economy. Likewise, smart city governance framework has to be considered a layered and multi-level concept focusing on issues of transparency and accountability to the citizens.
    • Biometric of Intent: A New Approach Identifying Potential Threat in Highly Secured Facilities

      Al Hamar, J.; Chamieh, J.; Al-Mohannadi, Hamad; Al Hamar, M.; Al-Mutlaq, A.; Musa, Ahmad S. (2018)
      Biometric of Intent (BoI) is a Computer Vision (CV) automation, using Artificial Intelligence (AI) techniques, which presents a new approach that extends the reach of the classic biometric identification process. It provides an efficient mechanism which deters the threats raised by unknown individuals who have deceitful intentions and who aim to deploy unlawful operations such as terrorist attacks. In this context, our proposed BoI model is based on a framework constructed upon an automated machine learning facial expression analysis system which can assist law enforcement agencies who intend to deploy a systematic preventive security approach that aims to reduce the risk of potential unlawful attacks by rogue individuals through the evaluation of their emotional state in relation to their malicious intent.
    • Understanding Awareness of Cyber Security Threat Among IT Employees

      Al-Mohannadi, Hamad; Awan, Irfan U.; Al Hamar, J.; Al Hamar, Y.; Shah, M.; Musa, Ahmad S. (2018)
      Cyber-attacks have been an increasing threat on people and organisations, which led to massive unpleasant impact. Therefore, there were many solutions to handle cyber-attacks, including Intrusion Detection Systems (IDS), Intrusion Prevention Systems (IPS). These solutions will provide a huge number of alarms that produce more are false positives. Therefore, the IDS tool result should be operated by a human intelligent be filtered effectively the huge amount of alerts to identify true positive attacks and perform accordingly to the incident response rule. This requires the IT employees to have enough knowledge and competency on operating IDS, IPS and incident handling. This paper aims to examine the awareness of cyber security threat among all IT employees, focusing on three domains: Knowledge, Monitoring and Prevention.
    • Malware Propagation Modelling in Peer-to-Peer Networks: A Review

      Musa, Ahmad S.; Al-Mohannadi, Hamad; Alhamar, J. (2018)
      Peer-to-Peer (P2P) network is increasingly becoming the most important means of trading content throughout the last years due to the constant evolvement of the cyber world. This popularity made the P2P network susceptible to the spread of malware. The detection of the cause of malware propagation is now critical to the survival of P2P networks. This paper offers a review of the current relevant mathematical propagation models that have been proposed to date to predict the propagation behavior of a malware in a P2P network. We analyzed the models proposed by researchers and experts in the field by evaluating their limitations and a possible alternative for improving the analysis of the expected behavior of a malware spread.
    • Exploring eleven year old children's understanding of well-being using well-being maps: Commonalities and divergences across areas of varying levels of deprivation and ethnic diversity in an English Qualitative Study

      McAuley, Colette (2018)
      The aim of this paper is to explore eleven year old children's understanding of well-being through their completion of Well-Being Maps and subsequent interviews on their content. The children were asked to describe the people, places and things which they viewed as important to their sense of well-being. The subsequent interviews explored their rationalisations for their choices. Ninety-two eleven year old children attending four schools with varying levels of deprivation and ethnic diversity took part in the study. This is the first section of an English study which is a part of the Multi-National Children's Understanding of Well-Being Study involving 26 countries which aims to explore how children conceptualise and experience well-being from a comparative and global perspective. Commonalities and divergences in the English children's responses were explored. Across the entire sample of 92 children, there were clear commonalities. Relationships with family, predominantly parents, were viewed as very important. The reasons provided were consistent love and affection; constant support, encouragement and protection; fun to be with. The duration of this quality of parent-child interaction appeared to be the key. Trust and a sense of security were the result. Relationships with friends were deemed important by over two thirds of the children. The qualities of these relationships mirrored those with the parents with a sense of trust and security being present. Where places and activities were included on their maps, they were often linked to important relationships. Activities appeared to be important in acknowledging the relationship but also maintaining it. Activities were also valued by the children for skill development. There were some differences across the sample with relationships with friends and grandparents being more reported as important in the two areas of high deprivation, irrespective of ethnic diversity. The level of material possessions and holidays abroad were much more frequently reported in the school serving the low deprivation area. At times, the explanations for differences appeared to be an interplay of socio-economic factors and religious and cultural traditions. Suggestions for further research on children's perspectives on factors important to their well-being are made.
    • Effect of transforming growth factor-β2 on biological regulation of multilayer primary chondrocyte culture

      Khaghani, Seyed A.; Akbarova, G.; Soon, C.F.; Dilbazi, G. (2018)
      Cytokines are extremely potent biomolecules that regulate cellular functions and play multiple roles in initiation and inhibition of disease. These highly specialised macromolecules are actively involved in control of cellular proliferation, apoptosis, cell migration and adhesion. This work, investigates the effect of transforming growth factor-beta2 (TGF-β2) on the biological regulation of chondrocyte and the repair of a created model wound on a multilayer culture system. Also the effect of this cytokine on cell length, proliferation, and cell adhesion has been investigated. Chondrocytes isolated from knee joint of rats and cultured at 4 layers. Each layer consisted of 2 × 105 cells/ml with and without TGF-β2. The expression of mRNA and protein levels of TGF-β receptors and Smad1, 3, 4, and 7 have been analysed by RT-PCR and western blot analysis. The effect of different supplementations in chondrocyte cell proliferation, cell length, adhesion, and wound repair was statistically analysed by One-way ANOVA test. Our results showed that the TGFβ2 regulates mRNA levels of its own receptors, and of Smad3 and Smad7. Also the TGF-β2 caused an increase in chondrocyte cell length, but decreased its proliferation rate and the wound healing process. TGF-β2 also decreased cell adhesion ability to the surface of the culture flask. Since, TGF-β2 increased the cell size, but showed negative effect on cell proliferation and adhesion of CHC, the effect of manipulated TGF-β2 with other growth factors and/or proteins needs to be investigated to finalize the utilization of this growth factor and design of scaffolding in treatment of different types of arthritis.
    • Impact of duty cycle on wear progression in variable-displacement vane oil pumps

      Doikin, Aleksandr; Habib Zadeh, Esmaeil; Campean, I. Felician; Proest, Martin; Brown, A.; Sherratt, A. (2018)
      Variable-displacement vane oil pumps are increasingly employed in automotive powertrains for their efficiency benefits through reduced losses. However, confirming long life reliability of a new commodity based on limited data available from product development tests and early field experience is a significant challenge, which is addressed by the work presented in this paper. The approach presented combines physical examination of pumps returned from tests, with analysis of damage factors for pump wear progression, and an analysis of functional parameters for the powertrain system focused on the cause effect linkages across the systems hierarchy. The metrology results from physical measurements of used parts provide useful insights for the wear progression and the expected service performance of the pump. The paper also expands towards a data driven approach based on ECU data analysis that could provide a pathway towards the development of online health monitoring and diagnostics of the oil pumps.
    • Dynamic modelling and operational optimisation of natural draft cooling towers

      Dhorat, A.; Al-Obaidi, M.A.; Mujtaba, Iqbal M. (2018)
      Natural draft cooling towers are subjected to dynamic air temperature and humidity ratio of air throughout the day. Their performances based on steady state model is restricted to single air temperature and humidity ratio of air values and thus are not accurate. In this work, a dynamic model for a natural draft cooling tower is developed. Air temperature and relative humidity data for Johannesburg were acquired to develop dynamic correlations for these two parameters and are embedded in the process model together with the dynamic model of the collection basin of the tower. A simple algorithm is proposed to solve the resulting boundary value problem. Finally, the common perception that seawater/river water should be used instead of freshwater as cooling medium is tested via optimisation where the operating costs of the process for two cooling mediums is minimised. The freshwater has been found to be cost effective cooling medium.
    • Does a more dynamic method of partial weight bearing instruction translate to improved protocols?

      Graham, Claire; Jeffrey, Sarah; Hellawell, Michael (2018)
      Background: Partial weight bearing protocols are commonly incorporated into rehabilitation to enhance recovery. Patients are often prescribed protocols that refer to a percentage of their body weight, such as 20% weight bearing, that should be placed through the healing limb during activities such as walking (gait). In order to achieve these partial weight baring protocols patients are usually provided with walking aids such as crutches. Accurate reproducibility of and compliance with these protocols could be considered essential to the rehabilitation process, however poor reproducibility of partial weight bearing protocols during crutch assisted gait using a current method of instruction has been shown. Aims: The aim of this study was to determine whether a more dynamic method of partial weight bearing protocol instruction, was more accurately reproduced. Methods: In total, 16 participants were randomly allocated to one of two groups and were taught 20% partial weight bearing using two different methods of instruction. A participant’s ability to reproduce their target load using crutch assisted gait was assessed using a force plate. Findings: The mean error for the static method of instruction was significantly greater than the more dynamic method. Conclusion: As seen previously, the static method of instruction of partial weight bearing protocols, using bathroom scales, does not seem to translate accurately to dynamic motion; however, the more dynamic method assessed in this study appears to result in more accurate reproducibility.
    • Serviceability performance of composite cellular beams with partial shear connection

      Lawson, R.M.; Lam, Dennis; Aggelopoulos, E.; Hanus, F. (2018-11)
      For composite cellular beams, additional deflections occur due to the loss of bending and shear stiffness at the opening positions and also due to slip in the shear connectors caused by partial shear connection. Design formulae are presented for the additional deflection of composite beams with circular openings or for cellular beams as a function of the proportionate depth of the openings. The simplified formulae are calibrated against finite element results for both cellular and solid web beams and also against measured deflections of a 15.3 m composite cellular beam test. This additional deflection is presented as a function of flexural and shear terms that are a function of the span:depth ratio. For modelling of cellular beams to determine deflections, the circular opening may be represented by an equivalent rectangular opening of length equal to 70% of the opening diameter.
    • Recovery and reuse of structural products from end-of-life buildings

      Hopkinson, P.; Chen, H-M.; Zhou, Kan; Wang, Y.; Lam, Dennis (2018)
      Buildings and construction have been identified as having the greatest potential for circular economy value creation. One source of value creation is to recover and reuse building products from end-of-service-life buildings, rather than destructive demolition and downcycling. While there is a trade in non-structural and heritage product recovery and reuse, the largest volume, mass and value of most buildings comprise structural elements – concrete, brick and masonry, and steel – which present many challenges. A comprehensive literature review confirms limited attention to innovation and advanced techniques to address these challenges and therefore the potential reuse of the stocks of accumulated building products globally and associated environmental benefits. Potential techniques being tested in an Engineering and Physical Sciences Research Council circular economy research programme are referenced as a key building block towards circular economy building system redesign.
    • An evaluation of modelling approaches and column removal time on progressive collapse of building

      Stephen, D.; Lam, Dennis; Forth, J.; Ye, J.; Tsavdaridis, K.D. (2019-02)
      Over the last few decades, progressive collapse disasters have drawn the attention of codified bodies around the globe; as a consequence, there has been a renewed research interest. Structural engineering systems are prone to progressive collapse when subjected to abnormal loads beyond the ultimate capacity of critical structural members. Sudden loss of critical structural member(s) triggers failure mechanisms which may result in a total or partial collapse of the structure proportionate or disproportionate to the triggering event. Currently, researchers adopt different modelling techniques to simulate the loss of critical load bearing members for progressive collapse assessment. GSA guidelines recommend a column removal time less than a tenth of the period of the structure in the vertical vibration mode. Consequently, this recommendation allows a wide range of column removal time which produces inconsistent results satisfying GSA recommendation. A choice of a load time history function assumed for gravity and the internal column force interaction affects the response of the structure. This paper compares different alternative numerical approaches to simulate the sudden column removal in frame buildings and to investigate the effect of rising time on the structural response.
    • Technology as a disruptive agent: Intergenerational perspectives

      Mahroof, Kamran; Weerakkody, Vishanth J.P.; Onkal, Dilek; Hussain, Zahid I. (2018)
      This study explores how British South Asian parents perceive their children’s technology consumption through their collectivist lenses and interdependent values. The findings for this qualitative study indicate that second and third generation South Asian parents acknowledge the benefits of children’s technology use; but largely perceive technology as a disruptive agent, whereby children are becoming isolated and increasingly independent within the household. The analysis aims to understand how parents view their children’s relationship with others as a result of technology consumption. Accordingly, this paper proposes an extension of the Construal of self conceptualisation and contributes a Techno-construal matrix that establishes a dyadic connection between technology consumption and cultural values. Overall, the study reveals that children display less inter-reliance and conformance typically associated with collectivist cultures, resulting from their technology use. Consequently, parents interpret their children’s shift from interdependence to more independence as a disruptive and unsettling phenomenon within the household.
    • Act now to close chemical-weapons loophole

      Shang, Lijun; Crowley, Michael J.A.; Dando, Malcolm R. (2018-10-18)
      As the Fourth Review Conference of the Chemical Weapons Convention meets next month, state parties need to address mounting concerns about the potential development and use of law-enforcement weapons involving chemical agents that act on the central nervous system (CNS).
    • Investigation of simultaneous effects of surface roughness, porosity and magnetic field of rough porous micro-fin under a convective-radiative heat transfer for improved electronic cooling of microprocessors

      Oguntala, G.A.; Sobamowo, G.; Eya, N.; Abd-Alhameed, Raed A. (2018)
      The ever-increasing demand for high-processing electronic systems has unequivocally called for improved microprocessor performance. However, increasing microprocessor performance requires increasing power and on-chip power density, both of which are associated with increased heat dissipation. Electronic cooling using fins have been identified as a reliable cooling approach. However, an investigation into the thermal behaviour of fin would help in the design of miniaturized, effective heatsinks for reliable microprocessor cooling. The aim of this paper is to investigates the simultaneous effects of surface roughness, porosity and magnetic field on the performance of a porous micro-fin under a convective-radiative heat transfer mechanism. The developed thermal model considers variable thermal properties according to linear, exponential and power laws, and are solved using Chebychev spectral collocation method. Parametric studies are carried using the numerical solutions to establish the influences of porosity, surface roughness, and magnetic field on the microfin thermal behaviour. Following the results of the simulation, it is established that the thermal efficiency of the micro-fin is significantly affected by the porosity, magnetic field, geometric ratio, nonlinear thermal conductivity parameter, thermogeometric parameter and the surface roughness of the micro-fin. However, the performance of the micro-fin decreases when it operates only in a convective environment. In addition, we establish that the fin efficiency ratio which is the ratio of the efficiency of the rough fin to the efficiency of the smooth fin is found to be greater than unity when the rough and smooth fins of equal geometrical, physical, thermal and material properties are subjected to the same operating condition. The investigation establishes that improved thermal management of electronic systems would be achieved using rough surface fins with porosity under the influences of the magnetic field.
    • Predicting visual acuity from visual field sensitivity in age-related macular degeneration

      Denniss, Jonathan; Baggaley, H.C.; Astle, A.T. (2018-09)
      Purpose: To investigate how well visual field sensitivity predicts visual acuity at the same locations in macular disease, and to assess whether such predictions may be useful for selecting an optimum area for fixation training. Methods: Visual field sensitivity and acuity were measured at nine locations in the central 10° in 20 people with AMD and stable foveal fixation. A linear mixed model was constructed to predict acuity from sensitivity, taking into account within-subject effects and eccentricity. Cross validation was used to test the ability to predict acuity from sensitivity in a new patient. Simulations tested whether sensitivity can predict nonfoveal regions with greatest acuity in individual patients. Results: Visual field sensitivity (P < 0.0001), eccentricity (P = 0.007), and random effects of subject on eccentricity (P = 0.043) improved the model. For known subjects, 95% of acuity prediction errors (predicted − measured acuity) fell within −0.21 logMAR to +0.18 logMAR (median +0.00 logMAR). For unknown subjects, cross validation gave 95% of acuity prediction errors within −0.35 logMAR to +0.31 logMAR (median −0.01 logMAR). In simulations, the nonfoveal location with greatest predicted acuity had greatest “true” acuity on median 26% of occasions, and median difference in acuity between the location with greatest predicted acuity and the best possible location was +0.14 logMAR (range +0.04 to +0.17). Conclusions: The relationship between sensitivity and acuity in macular disease is not strongly predictive. The location with greatest sensitivity on microperimetry is unlikely to represent the location with the best visual acuity, even if eccentricity is taken into account.
    • Application of approximate analytical technique using the homotopy perturbation method to study the inclination effect on the thermal behavior of porous fin heat sink

      Oguntala, G.A.; Sobamowo, G.; Ahmed, Y.; Abd-Alhameed, Raed A. (2018-10)
      This article presents the homotopy perturbation method (HPM) employed to investigate the effects of inclination on the thermal behavior of a porous fin heat sink. The study aims to review the thermal characterization of heat sink with the inclined porous fin of rectangular geometry. The study establishes that heat sink of an inclined porous fin shows a higher thermal performance compared to a heat sink of equal dimension with a vertical porous fin. In addition, the study also shows that the performance of inclined or tilted fin increases with decrease in length–thickness aspect ratio. The study further reveals that increase in the internal heat generation variable decreases the fin temperature gradient, which invariably decreases the heat transfer of the fin. The obtained results using HPM highlights the accuracy of the present method for the analysis of nonlinear heat transfer problems, as it agrees well with the established results of Runge–Kutta.
    • In vivo selectivity and localization of reactive oxygen species (ROS) induction by osmium anticancer complexes that circumvent platinum resistance

      Coverdale, J.P.C.; Bridgewater, H.E.; Song, J-I.; Smith, N.A.; Barry, Nicolas P.E.; Bagley, I.; Sadler, P.J.; Romero-Canelon, I. (2018-10)
      Platinum drugs are widely used for cancer treatment. Other precious metals are promising, but their clinical progress depends on achieving different mechanisms of action to overcome Pt-resistance. Here, we evaluate 13 organo-Os complexes: 16-electron sulfonyl-diamine catalysts [(η6-arene)Os(N,N′)], and 18-electron phenylazopyridine complexes [(η6-arene)Os(N,N’)Cl/I]+ (arene = p-cymene, biphenyl, or terphenyl). Their antiproliferative activity does not depend on p21 or p53 status, unlike cisplatin, and their selective potency toward cancer cells involves the generation of reactive oxygen species. Evidence of such a mechanism of action has been found both in vitro and in vivo. This work appears to provide the first study of osmium complexes in the zebrafish model, which has been shown to closely model toxicity in humans. A fluorescent osmium complex, derived from a lead compound, was employed to confirm internalization of the complex, visualize in vivo distribution, and confirm colocalization with reactive oxygen species generated in zebrafish.
    • Interaction between closely packed array antenna elements using metasurface for applications such as MIMO systems and synthetic aperture radars

      Alibakhshikenari, M.; Virdee, B.S.; Shukla, P.; See, C.H.; Abd-Alhameed, Raed A.; Khalily, M.; Falcone, F.; Limiti, E. (2018)
      The paper presents a technique to enhance the isolation between adjacent radiating elements which is common in densely packed antenna arrays. Such antennas provide frequency beam-scanning capability needed in Multiple-Input Multiple-Output (MIMO) systems and Synthetic Aperture Radars (SARs). The method proposed here uses a metamaterial decoupling slab (MTMDS), which is located between radiating elements, to suppress mutual-coupling between the elements that would otherwise degrade the antenna efficiency and performance in both the transmit and receive mode. The proposed MTM-DS consists of mirror imaged Eshaped slits engraved on a microstrip patch with inductive stub. Measured results confirm over 9–11 GHz with no MTM-DS the average isolation (S12) is -27 dB; however, with MTM-DS the average isolation improves to -38 dB. With this technique the separation between the radiating element can be reduced to 0.66λo, where λ0 is free space wavelength at 10 GHz. In addition, with this technique there is 15% improvement in operating bandwidth. At frequencies of high impedance match of 9.95 GHz and 10.63 GHz the gain is 4.52 dBi and 5.40 dBi, respectively. Furthermore, the technique eliminates poor front-to-back ratio encountered in other decoupling methods. MTM-DS is also relatively simple to implement. Assuming adequate space is available between adjacent radiators the MTM-DS can be fixed retrospectively on existing antenna arrays, which makes the proposed method versatile.
    • Indoor location identification technologies for real-time IoT-based applications: an inclusive survey

      Oguntala, G.A.; Abd-Alhameed, Raed A.; Jones, Stephen F.; Noras, James M.; Patwary, M.; Rodriguez, J. (2018-11)
      The advent of the Internet of Things has witnessed tremendous success in the application of wireless sensor networks and ubiquitous computing for diverse smart-based applications. The developed systems operate under different technologies using different methods to achieve their targeted goals. In this treatise, we carried out an inclusive survey on key indoor technologies and techniques, with to view to explore their various benefits, limitations, and areas for improvement. The mathematical formulation for simple localization problems is also presented. In addition, an empirical evaluation of the performance of these indoor technologies is carried out using a common generic metric of scalability, accuracy, complexity, robustness, energy-efficiency, cost and reliability. An empirical evaluation of performance of different RF-based technologies establishes the viability of Wi-Fi, RFID, UWB, Wi-Fi, Bluetooth, ZigBee, and Light over other indoor technologies for reliable IoT-based applications. Furthermore, the survey advocates hybridization of technologies as an effective approach to achieve reliable IoT-based indoor systems. The findings of the survey could be useful in the selection of appropriate indoor technologies for the development of reliable real-time indoor applications. The study could also be used as a reliable source for literature referencing on the subject of indoor location identification.