• Automatic monitoring and quantitative characterization of sedimentation dynamics for non-homogenous systems based on image profile analysis

      Lu, X.; Liao, Z.; Li, X.; Wang, M.; Wu, L.; Li, H.; York, Peter; Xu, X.; Yin, X.; Zhang, J. (2015-09)
      Sedimentation of non-homogeneous systems is the typical phenomenon indicating the physical instability as a key measure to the quality control of the preparation products. Currently, the determination methods for the sedimentation of non-homogeneous preparations are based on manual measurement or semi-quantitative observation, lacking of either automation or quantitative dynamic analysis. The purpose of this research was to realize automatic and quantitative monitoring of the sedimentation dynamics for non-homogenous systems as suspension, emulsions at laboratory level. Non-contact measurement method has been established to determine the sedimentation behaviors in a standard quartz tube for sedimentation, with internal diameter and height 23 mm and 215 mm, respectively, with controlled temperature and light intensity. As high performance camera has been equipped, the sedimentation images with high spatial and temporal resolution could be acquired, which can continuously capture sedimentation images with the resolution of 2048 x 2048 pixel at a maximum rate of 60 slides/s. All the pictures were processed to extract the luminance matrix top-down along the fixed vertical midline of each picture, which implied sedimentation characteristics of the system at the moment the picture was taken. Combining all the luminance matrixes along vertical middle lines of the pictures, a time-luminance matrix profile was obtained. Digital image processing techniques were used to eliminate interference and establish a three-dimensional surface model of the sedimentation dynamics. Then, the derivative mutation algorithm has been developed for the intelligent identification of sedimentation interface with threshold optimization so as to quantitatively analyze the sedimentation dynamics with visualization. The sedimentation curve and sedimentation dynamic equation of the non-homogeneous system were finally outputted by numerical fitting. The methodology was validated for great significance in determinations of small volume samples, parallel control multiple batches, and long period of time automatic measurement. (C) 2015 Elsevier B.V. All rights reserved.
    • Automatic Reconstruction and Web Visualization of Complex PDE Shapes

      Pang, M.; Sheng, Y.; Gonzalez Castro, Gabriela; Sourin, A.; Ugail, Hassan (2010)
    • Automatic Selection of Verification Tools for Efficient Analysis of Biochemical Models

      Bakir, M.E.; Konur, Savas; Gheorghe, Marian; Krasnogor, N.; Stannett, M. (2018)
      Motivation: Formal verification is a computational approach that checks system correctness (in relation to a desired functionality). It has been widely used in engineering applications to verify that systems work correctly. Model checking, an algorithmic approach to verification, looks at whether a system model satisfies its requirements specification. This approach has been applied to a large number of models in systems and synthetic biology as well as in systems medicine. Model checking is, however, computationally very expensive, and is not scalable to large models and systems. Consequently, statistical model checking (SMC), which relaxes some of the constraints of model checking, has been introduced to address this drawback. Several SMC tools have been developed; however, the performance of each tool significantly varies according to the system model in question and the type of requirements being verified. This makes it hard to know, a priori, which one to use for a given model and requirement, as choosing the most efficient tool for any biological application requires a significant degree of computational expertise, not usually available in biology labs. The objective of this paper is to introduce a method and provide a tool leading to the automatic selection of the most appropriate model checker for the system of interest. Results: We provide a system that can automatically predict the fastest model checking tool for a given biological model. Our results show that one can make predictions of high confidence, with over 90% accuracy. This implies significant performance gain in verification time and substantially reduces the “usability barrier” enabling biologists to have access to this powerful computational technology.
    • Automatic shape optimisation of pharmaceutical tablets using Partial Differential Equations

      Ahmat, Norhayati; Gonzalez Castro, Gabriela; Ugail, Hassan (2014-01)
      Pharmaceutical tablets have been the most dominant form for drug delivery and most of them are used in the oral administration of drugs. These tablets need to be strong enough so that they can tolerate external stresses. Hence, during the design process, it is important to produce tablets with maximum mechanical strength while conserving the properties of powder form components. The mechanical properties of these tablets are assessed by measuring the tensile strength, which is commonly measured using diametrical or axial compression tests. This work describes the parametric design and optimisation of solid pharmaceutical tablets in cylindrical and spherical shapes, which are obtained using a formulation based on the use of Partial Differential Equations (PDEs) for shape design. The PDE-based formulation is capable of parameterised complex shapes using the information from some boundary curves that describe the shape. It is shown that the optimal design of pharmaceutical tablets with a particular volume and maximum strength can be obtained using an automatic design optimisation which is performed by combining the PDE method and a standard method for numerical optimisation.
    • Automatic Short-Term Solar Flare Prediction Using Machine Learning and Sunspot Associations.

      Qahwaji, Rami S.R.; Colak, Tufan (Springer, 2007)
      In this paper, a machine-learning-based system that could provide automated short-term solar flare prediction is presented. This system accepts two sets of inputs: McIntosh classification of sunspot groups and solar cycle data. In order to establish a correlation between solar flares and sunspot groups, the system explores the publicly available solar catalogues from the National Geophysical Data Center to associate sunspots with their corresponding flares based on their timing and NOAA numbers. The McIntosh classification for every relevant sunspot is extracted and converted to a numerical format that is suitable for machine learning algorithms. Using this system we aim to predict whether a certain sunspot class at a certain time is likely to produce a significant flare within six hours time and if so whether this flare is going to be an X or M flare. Machine learning algorithms such as Cascade-Correlation Neural Networks (CCNNs), Support Vector Machines (SVMs) and Radial Basis Function Networks (RBFN) are optimised and then compared to determine the learning algorithm that would provide the best prediction performance. It is concluded that SVMs provide the best performance for predicting whether a McIntosh classified sunspot group is going to flare or not but CCNNs are more capable of predicting the class of the flare to erupt. A hybrid system that combines a SVM and a CCNN is suggested for future use.
    • Automatic sunspots detection on SODISM solar images

      Alasta, Amro F.; Algamudi, Abdulrazag; Qahwaji, Rami S.R.; Ipson, Stanley S.; Nagem, Tarek A. (2017)
      The surface of the sun often shows visible sunspots which are located in magnetically active regions of the Sun, and whose number is an indicator of the Sun’s magnetic activity. The detection and classification of sunspots are useful techniques in the monitoring and prediction of solar activity. The automated detection of sunspots from digital images is complicated by their irregularities in shape and variable contrast and intensity compared with their surrounding area. The main aim of this paper is to detect sunspots using images from the Solar Diameter Imager and Surface Mapper (SODISM) on the PICARD satellite and calculate their filling factors. A comparison over time with sunspot numbers obtained using images from the SOHO satellite is also presented.
    • An automatic test data generation from UML state diagram using genetic algorithm.

      Doungsa-ard, Chartchai; Dahal, Keshav P.; Hossain, M. Alamgir; Suwannasart, T. (IEEE, 2007)
      Software testing is a part of software development process. However, this part is the first one to miss by software developers if there is a limited time to complete the project. Software developers often finish their software construction closed to the delivery time, they usually don¿t have enough time to create effective test cases for testing their programs. Creating test cases manually is a huge work for software developers in the rush hours. A tool which automatically generates test cases and test data can help the software developers to create test cases from software designs/models in early stage of the software development (before coding). Heuristic techniques can be applied for creating quality test data. In this paper, a GA-based test data generation technique has been proposed to generate test data from UML state diagram, so that test data can be generated before coding. The paper details the GA implementation to generate sequences of triggers for UML state diagram as test cases. The proposed algorithm has been demonstrated manually for an example of a vending machine.
    • Automotive gas turbine regulation

      Ebrahimi, Kambiz M.; Whalley, R. (2004-05)
      A multivariable model of an automotive gas turbine, obtained from the linearized system equations is investigated. To facilitate vehicle speed changes, whilst protecting the system against thermal damage, control of the power turbine inlet gas temperature and gas generator speed is proposed by feedback regulation. Fuel flow and the power turbine nozzle area variations are the selected, manipulatable inputs. Owing to the limited control energy available for regulation purposes a multivariable, optimum, minimum control effort strategy is employed in the inner loop controller design study. Simulated, open and closed loop system responses are presented for purposes of comparison. Significant improvements in the transient response interaction reaction times and low steady state output interaction achieved using passive compensation and output feedback alone. Simplification of the closed loop configuration is proposed in the final implementation without performance penalties.
    • Automotive IVHM: Towards Intelligent Personalised Systems Healthcare

      Campean, I. Felician; Neagu, Daniel; Doikin, Aleksandr; Soleimani, Morteza; Byrne, Thomas J.; Sherratt, A. (2019)
      Underpinned by a contemporary view of automotive systems as cyber-physical systems, characterised by progressively open architectures increasingly defined by their interaction with the users and the smart environment, this paper provides a critical and up-to-date review of automotive Integrated Vehicle Health Management (IVHM) systems. The paper discusses the challenges with prognostics and intelligent health management of automotive systems, and proposes a high-level framework, referred to as the Automotive Healthcare Analytic Factory, to systematically collect and process heterogeneous data from across the product lifecycle, towards actionable insight for personalised healthcare of systems.
    • Automotive timing belt life laws and a user design guide

      Childs, T.H.C.; Dalgarno, K.W.; Day, Andrew J.; Moore, R.B. (1998)
      The paper presents a computer-based guide of the effect of layout and loading (tension and torque) on the timing belt life and uses it to show the sensitivity of life to changed conditions in an automotive camshaft drive. The predictions are in line with experience. The guide requires belt property information, such as the tooth and tension member stiffness, the friction coefficient between the belt lands and pulleys and the pitch difference from the pulley, in order to calculate the tooth deflections caused by the belt loadings on the various pulleys in the layout. It also requires information on how the belt life depends on the tooth deflections. Experimental data are presented on the life±deflection relations of a commercial automotive timing belt tested between 100 and 140 8C, although the bulk of the data has been obtained at 120 8C. Four different life laws have been found, depending on whether the failure-initiating deflection occurred on a driver or a driven pulley, and whether at entry to or exit from the pulley. Theoretical analysis of the tooth loading in the partial meshing state shows that, in three cases out of the four, the different life±deflection laws transform to a single relation between the life and the tooth root strain. The exception is failure caused by driven entry conditions; work is continuing to understand better the causes of failure in this circumstance
    • Axial behavior of reinforced concrete short columns strengthened with wire rope and T-shaped steel plate units.

      Yang, Keun-Hyeok; Ashour, Ashraf F.; Lee, E-T. (2009-03)
      This paper presents a relatively simple column strengthening procedure using unbonded wire rope and T-shaped steel plate units. Twelve strengthened columns and an unstrengthened control column were tested to failure under concentric axial load to explore the significance and shortcomings of the proposed strengthening technique. The main variables investigated were the volume ratio of wire ropes as well as geometrical size and configuration of T-shaped steel plates. Axial load capacity and ductility ratio of columns tested were compared with predictions obtained from the equation specified in ACI 318-05 and models developed for conventionally tied columns, respectively. The measured axial load capacities of all strengthened columns were higher than predictions obtained from ACI 318-05, indicating that the ratio of the measured and predicted values increased with the increase of volume ratio of wire ropes and flange width of T-shaped steel plates. In addition, at the same lateral reinforcement index, a much higher ductility ratio was exhibited by strengthened columns having a volume ratio of wire ropes above 0·0039 than tied columns. The ductility ratio of strengthened columns tested increased with the increase of flange width, thickness, and web height of T-shaped steel plates. A mathematical model for the prediction of stress–strain characteristics of confined concrete using the proposed strengthening technique is developed, that was in good agreement with test results.
    • Axial Capacity of Circular Concrete¿filled Tube Columns.

      Giakoumelis, G.; Lam, Dennis (2004)
      The behaviour of circular concrete-filled steel tubes (CFT) with various concrete strengths under axial load is presented. The effects of steel tube thickness, the bond strength between the concrete and the steel tube, and the confinement of concrete are examined. Measured column strengths are compared with the values predicted by Eurocode 4, Australian Standards and American Codes. 15 specimens were tested with 30, 60 and 100 N/mm2 concrete strength, with a D/t ratio from 22.9 to 30.5. All the columns were 114 mm in diameter and 300 mm in length. The effect due to concrete shrinkage is critical for high-strength concrete and negligible for normal strength concrete. All three codes predicted lower values than that measured during the experiments. Eurocode 4 gives the best estimation for both CFT with normal and high-strength concrete.
    • Axial Capacity of Concrete Filled Stainless Steel Columns

      Lam, Dennis; Wong, K.K.Y. (2005)
      Concrete filled steel columns have been used widely in structures throughout the world in recent years especially in Australia and the Far East. This increase in use is due to the significant advantages that concrete filled steel columns offer in comparison to more traditional construction methods. Composite columns consist of a combination of concrete and steel and make use of these constituent material's best properties. The use of composite columns can result in significant savings in column size, which ultimately can lead to significant economic savings. This reduction in column size can provide substantial benefits where floor space is at a premium such as in car parks and office blocks. The use of stainless steel column filled with concrete is new and innovative, not only provides the advantage mentioned above, but also durability associated with the stainless steel material. This paper concentrates on the axial capacity of the concrete filled stainless steel columns. A series of tests was performed to consider the behaviour of short composite stainless steel columns under axial compressive loading, covering austenitic stainless steels square hollow sections filled with normal and high strength concrete. Comparisons between Eurocode 4, ACI-318 and the Australian Standards with the findings of this research were made and comment.
    • Axial Capacity of Concrete-Filled Steel Elliptical Hollow Sections

      Lam, Dennis; Testo, N. (2007)
      Concrete filled steel tube (CFST) columns are becoming increasingly popular due to the advantages they offered. They are not only considered aesthetically pleasing but can also offer significant improvement in axial capacity without increases in crosssectional area being required. Elliptical steel hollow sections represent a recent and rare addition to the range of cross-sections available to structural engineers, however, despite widespread interest in their application, a lack of verified design guidance is inhibiting uptake. The use of elliptical steel hollow section with concrete infill is new and innovative, not only provides the advantage mentioned above, but also on the basis of both architectural appeal and structural efficiency. The aim of this paper is to investigate the behaviour of the elliptical CFSTs under axial loading. A total of 12 specimens were tested with wall thicknesses of 4 mm, 5 mm, 6.3 mm and concrete core strength of 30 MPa. This paper reported on the behaviour of concrete filled elliptical hollow sections under axial load. The effect of the wall thickness of the steel section, the bond between steel and concrete and the concrete confinement are presented.
    • Axial compressive behaviour of stub concrete-filled columns with elliptical stainless steel hollow sections.

      Dai, Xianghe; Lam, Dennis (2010)
      This paper presents the axial compressive behaviour of stub concrete-filled columns with elliptical stainless steel and carbon steel hollow sections. The finite element method developed via ABAQUS/Standard solver was used to carry out the simulations. The accuracy of the FE modelling and the proposed confined concrete stress-strain model were verified against experimental results. A parametric study on stub concrete-filled columns with various elliptical hollow sections made with stainless steel and carbon steel was conducted. The comparisons and analyses presented in this paper outline the effect of hollow sectional configurations to the axial compressive behaviour of elliptical concrete-filled steel tubular columns, especially the merits of using stainless steel hollow sections is highlighted.
    • Axial loading of bonded rubber blocks.

      Horton, J.M.; Tupholme, Geoffrey E.; Gover, Michael J.C. (2002)
      Axially loaded rubber blocks of long, thin rectangular and circular cross section whose ends are bonded to rigid plates are studied. Closed-form expressions, which satisfy exactly the governing equations and conditions based upon the classical theory of elasticity, are derived for the total axial deflection and stress distribution using a superposition approach. The corresponding relations are presented for readily calculating the apparent Young's modulus, Ea, the modified modulus, E'a, and the deformed lateral profiles of the blocks. From these, improved approximate elementary expressions for evaluating Ea and E'a are deduced. These estimates, and the precisely found values, agree for large values of the shape factor S, with those previously suggested, but also fit the experimental data more closely for small values of S. Confirmation is provided that the assumption of a parabolic lateral profile is invalid for small values of S.
    • Axial loading of elliptical-section bonded rubber blocks

      Tupholme, Geoffrey E.; Horton, J.M. (2009-07-13)
      Closed-form expressions for the small axial deflection and stress distribution of axially loaded rubber blocks of elliptical cross-section, whose ends are bonded to rigid plates, are derived using a superposition approach. The governing equations and conditions are satisfied exactly, based upon the classical theory of elasticity. Easily calculable expressions are derived for the corresponding apparent Young¿s modulus and the modified apparent Young¿s modulus in forms analogous to those previously given for blocks of circular cross-section.
    • An Axiomatic Categorisation Framework for the Dynamic Alignment of Disparate Functions in Cyber-Physical Systems

      Byrne, Thomas J.; Doikin, Aleksandr; Campean, I. Felician; Neagu, Daniel (2019-07)
      Advancing Industry 4.0 concepts by mapping the product of the automotive industry on the spectrum of Cyber Physical Systems, we immediately recognise the convoluted processes involved in the design of new generation vehicles. New technologies developed around the communication core (IoT) enable novel interactions with data. Our framework employs previously untapped data from vehicles in the field for intelligent vehicle health management and knowledge integration into design. Firstly, the concept of an inter-disciplinary artefact is introduced to support the dynamic alignment of disparate functions, so that cyber variables change when physical variables change. Secondly, the axiomatic categorisation (AC) framework simulates functional transformations from artefact to artefact, to monitor and control automotive systems rather than components. Herein, an artefact is defined as a triad of the physical and engineered component, the information processing entity, and communication devices at their interface. Variable changes are modelled using AC, in conjunction with the artefacts, to aggregate functional transformations within the conceptual boundary of a physical system of systems.