ORCID Profile
0000-0003-0660-2312
Current Organisation
University of Adelaide
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Publisher: Elsevier BV
Date: 02-2017
Publisher: IEEE
Date: 12-2010
Publisher: IEEE
Date: 05-2011
Publisher: MDPI AG
Date: 09-11-2022
DOI: 10.3390/S22228632
Abstract: Structural optimisation of robotic manipulators is critical for any manipulator used in confined semi-structured environments, such as in agriculture. Many robotic manipulators utilised in semi-structured environments retain the same characteristics and dimensions as those used in fully-structured industrial environments, which have been proven to experience low dexterity and singularity issues in challenging environments due to their structural limitations. When implemented in environments other than fully-structured industrial environments, conventional manipulators are liable to singularity, joint limits and workspace obstacles. This makes them inapplicable in confined semi-structured environments, as they lack the flexibility to operate dexterously in such challenging environments. In this paper, structural optimisation of a hyper-redundant cable-driven manipulator is proposed to improve its performance in semi-structured and challenging confined spaces, such as in agricultural settings. The optimisation of the manipulator design is performed in terms of its manipulability and kinematics. The lengths of the links and the joint angles are optimised to minimise any error between the actual and desired position/orientation of the end-effector in a confined semi-structured task space, as well as to provide optimal flexibility for the manipulators to generate different joint configurations for obstacle avoidance in confined environments. The results of the optimisation suggest that the use of a redundant manipulator with rigid short links can result in performance with higher dexterity in confined, semi-structured environments, such as agricultural greenhouses.
Publisher: IEEE
Date: 09-2015
Publisher: IEEE
Date: 2006
Publisher: IEEE
Date: 10-2009
Publisher: IEEE
Date: 11-2014
Publisher: IEEE
Date: 10-2019
Publisher: IEEE
Date: 10-2009
Publisher: Wiley
Date: 09-2010
DOI: 10.1002/ASJC.231
Publisher: SAGE Publications
Date: 03-2019
Abstract: Diabetes mellitus is a persistent metabolic syndrome caused by impaired capability of the body’s production and usage of insulin. This impaired capability results in chronic hyperglycaemia, the elevated glucose concentration in the bloodstream, which may lead to many incurable complications. To escape this dire situation, a proper model-based exogenous infusion of insulin bolus is required, which is usually established via different feedback control strategies. In this article, the authors present a mathematical model–based robust integral sliding mode control approach for stabilization of internal glucose–insulin regulatory system in type-1 diabetic patient. Since the state variables of the system are not directly available to the controller, a uniform exact differentiator observer is employed to accomplish the aforementioned task. In the proposed control law, the incorporation of integral term in the switching manifold eliminates the reaching phase, which causes the sliding mode to establish from the very initial point, thus enhances the robustness property of the proposed control scheme. Moreover, the chattering problem is also substantially suppressed to a considerable extent along a defined manifold. To verify the theoretical analysis, the proposed control law is verified via computer simulations which demonstrate the effectiveness of the proposed control law against the external perturbations, that is, unannounced meal intake and physical exercise.
Publisher: Springer International Publishing
Date: 31-05-2019
Publisher: Copernicus GmbH
Date: 28-06-2013
DOI: 10.5194/NHESS-13-1679-2013
Abstract: Abstract. An earthquake is one of the most destructive natural disasters that can occur, often killing many people and causing large material losses. Hence, the ability to predict earthquakes may reduce the catastrophic effects caused by this phenomenon. The geoelectric field is a feature that can be used to predict earthquakes (EQs) because of significant changes in the litude of the signal prior to an earthquake. This paper presents a detailed analysis of geoelectric field signals of earthquakes which occurred in 2008 in Greece. In 2008, 12 earthquakes occurred in Greece. Five of them were recorded with magnitudes greater than Ms = 5R (5R), while seven of them were recorded with magnitudes greater than Ms = 6R (6R). In the analysis, the 1st significant changes of the geoelectric field signal are detected. Then, the signal is segmented and windowed. The adaptive short-time Fourier transform (adaptive STFT) technique is then applied to the windowed signal, and the spectral analysis is performed thereafter. The results show that the 1st significant changes of the geoelectric field prior to an earthquake have a significant litude frequency spectrum compared to other conditions, i.e. normal days and the day of the earthquake, which can be used as input parameters for earthquake prediction.
Publisher: IEEE
Date: 05-2015
Publisher: Springer Science and Business Media LLC
Date: 28-12-2013
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 2017
Publisher: IEEE
Date: 12-2016
Publisher: IEEE
Date: 12-2010
Publisher: IEEE
Date: 12-2012
Publisher: Inderscience Publishers
Date: 2012
Publisher: Elsevier BV
Date: 03-2017
Publisher: IEEE
Date: 10-2010
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 07-2010
Publisher: Elsevier BV
Date: 11-2011
Publisher: IEEE
Date: 05-2009
Publisher: American Psychological Association (APA)
Date: 2015
DOI: 10.1037/TRA0000050
Abstract: For this study, we examined the nature of the unique relationships trait-negative affect and compassion satisfaction had with compassion fatigue and its components of secondary traumatic stress and burnout in 273 nurses from 1 metropolitan tertiary acute hospital in Western Australia. Participants completed the Professional Quality of Life Scale (Stamm, 2010), Depression Anxiety Stress Scale (Lovibond & Lovibond, 2004), and the State-Trait Anxiety Inventory (Spielberger, Gorsuch, Lushene, Vagg, & Jacobs, 1983). Bivariate correlation and hierarchical regression analyses were performed to examine and investigate 4 hypotheses. The results demonstrate a clear differential pattern of relationships with secondary traumatic stress and burnout for both trait-negative affect and compassion satisfaction. Trait-negative affect was clearly the more important factor in terms of its contribution to overall compassion fatigue and secondary traumatic stress. In contrast, compassion satisfaction's unique protective relationship only related to burnout, and not secondary traumatic stress. The results are therefore consistent with the view that compassion satisfaction may be an important internal resource that protects against burnout, but is not directly influential in protecting against secondary traumatic stress for nurses working in an acute-care hospital environment. With the projected nursing workforce shortages in Australia, it is apparent that a further understanding is warranted of how such personal variables may work as protective and risk factors.
Publisher: IEEE
Date: 02-2009
Publisher: UNSYS Digital
Date: 29-05-2018
Publisher: IEEE
Date: 11-2009
Publisher: IEEE
Date: 08-2010
Publisher: IEEE
Date: 06-2013
Publisher: American Scientific Publishers
Date: 10-2016
Publisher: Public Library of Science (PLoS)
Date: 20-01-2022
DOI: 10.1371/JOURNAL.PONE.0260480
Abstract: The increasing energy demand and the target to reduce environmental pollution make it essential to use efficient and environment-friendly renewable energy systems. One of these systems is the Photovoltaic (PV) system which generates energy subject to variation in environmental conditions such as temperature and solar radiations. In the presence of these variations, it is necessary to extract the maximum power via the maximum power point tracking (MPPT) controller. This paper presents a nonlinear generalized global sliding mode controller (GGSMC) to harvest maximum power from a PV array using a DC-DC buck-boost converter. A feed-forward neural network (FFNN) is used to provide a reference voltage. A GGSMC is designed to track the FFNN generated reference subject to varying temperature and sunlight. The proposed control strategy, along with a modified sliding mode control, eliminates the reaching phase so that the sliding mode exists throughout the time. The system response observes no chattering and harmonic distortions. Finally, the simulation results using MATLAB/Simulink environment demonstrate the effectiveness, accuracy, and rapid tracking of the proposed control strategy. The results are compared with standard results of the nonlinear backstepping controller under abrupt changes in environmental conditions for further validation.
Publisher: ICI Bucharest
Date: 07-01-2018
Publisher: IEEE
Date: 05-2015
Publisher: IEEE
Date: 11-2014
Publisher: IEEE
Date: 05-2011
Publisher: Springer Science and Business Media LLC
Date: 02-01-2020
Publisher: IEEE
Date: 2006
Publisher: Springer Science and Business Media LLC
Date: 06-2010
Publisher: IEEE
Date: 09-2010
Publisher: IOP Publishing
Date: 03-2017
Publisher: Wiley
Date: 27-10-2014
DOI: 10.1111/AOR.12370
Abstract: The present study investigates the response of implantable rotary blood pump (IRBP)-assisted patients to exercise and head-up tilt (HUT), as well as the effect of alterations in the model parameter values on this response, using validated numerical models. Furthermore, we comparatively evaluate the performance of a number of previously proposed physiologically responsive controllers, including constant speed, constant flow pulsatility index (PI), constant average pressure difference between the aorta and the left atrium, constant average differential pump pressure, constant ratio between mean pump flow and pump flow pulsatility (ratioP I or linear Starling-like control), as well as constant left atrial pressure ( P l a ¯ ) control, with regard to their ability to increase cardiac output during exercise while maintaining circulatory stability upon HUT. Although native cardiac output increases automatically during exercise, increasing pump speed was able to further improve total cardiac output and reduce elevated filling pressures. At the same time, reduced venous return associated with upright posture was not shown to induce left ventricular (LV) suction. Although P l a ¯ control outperformed other control modes in its ability to increase cardiac output during exercise, it caused a fall in the mean arterial pressure upon HUT, which may cause postural hypotension or patient discomfort. To the contrary, maintaining constant average pressure difference between the aorta and the left atrium demonstrated superior performance in both exercise and HUT scenarios. Due to their strong dependence on the pump operating point, PI and ratioPI control performed poorly during exercise and HUT. Our simulation results also highlighted the importance of the baroreflex mechanism in determining the response of the IRBP-assisted patients to exercise and postural changes, where desensitized reflex response attenuated the percentage increase in cardiac output during exercise and substantially reduced the arterial pressure upon HUT.
Publisher: Elsevier BV
Date: 2012
Publisher: IOP Publishing
Date: 03-2017
Publisher: IOP Publishing
Date: 11-2017
Publisher: IOP Publishing
Date: 11-2017
Publisher: Informa UK Limited
Date: 17-05-2016
DOI: 10.1080/10400435.2016.1140688
Abstract: Two-wheeled wheelchairs are considered highly nonlinear and complex systems. The systems mimic a double-inverted pendulum scenario and will provide better maneuverability in confined spaces and also to reach higher level of height for pick and place tasks. The challenge resides in modeling and control of the two-wheeled wheelchair to perform comparably to a normal four-wheeled wheelchair. Most common modeling techniques have been accomplished by researchers utilizing the basic Newton's Laws of motion and some have used 3D tools to model the system where the models are much more theoretical and quite far from the practical implementation. This article is aimed at closing the gap between the conventional mathematical modeling approaches where the integrated 3D modeling approach with validation on the actual hardware implementation was conducted. To achieve this, both nonlinear and a linearized model in terms of state space model were obtained from the mathematical model of the system for analysis and, thereafter, a 3D virtual prototype of the wheelchair was developed, simulated, and analyzed. This has increased the confidence level for the proposed platform and facilitated the actual hardware implementation of the two-wheeled wheelchair. Results show that the prototype developed and tested has successfully worked within the specific requirements established.
Publisher: IEEE
Date: 05-2015
Publisher: MDPI AG
Date: 08-02-2021
DOI: 10.3390/APP11041546
Abstract: This paper presents a thorough review on the system identification techniques applied to flapping wing micro air vehicles (FWMAVs). The main advantage of this work is to provide a solid background and domain knowledge of system identification for further investigations in the field of FWMAVs. In the system identification context, the flapping wing systems are first categorized into tailed and tailless MAVs. The most recent developments related to such systems are reported. The system identification techniques used for FWMAVs can be classified into time-response based identification, frequency-response based identification, and the computational fluid-dynamics based computation. In the system identification scenario, least mean square estimation is used for a beetle mimicking system recognition. In the end, this review work is concluded and some recommendations for the researchers working in this area are presented.
Publisher: IEEE
Date: 09-2010
Publisher: IEEE
Date: 05-2011
Publisher: IOP Publishing
Date: 20-12-2013
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 10-2014
Publisher: IEEE
Date: 05-2011
Publisher: Penerbit UTM Press
Date: 23-06-2016
DOI: 10.11113/JT.V78.9181
Abstract: This paper presents an integral sliding mode (ISM) control for a case of negative imaginary (NI) systems. A gantry crane system (GCS) is considered in this work. ISM is a nonlinear control method introducing significant properties of precision, robustness, stress-free tuning and implementation. The GCS model considered in this work is derived based on the x direction and sway motion of the payload. The GCS is a negative imaginary (NI) system with a single pole at the origin. ISM consist of two blocks the inner block made up of a pole placement controller (NI controller), designed using linear matrix inequality for robustness and outer block made up of sliding mode control to reject disturbances. The ISM is designed to control position tracking and anti-swing payload motion. The robustness of the control scheme is tested with an input disturbance of a sine wave signal. The simulation results show the effectiveness of the control scheme.
Publisher: IEEE
Date: 05-2011
Publisher: Springer Berlin Heidelberg
Date: 2007
Publisher: IEEE
Date: 05-2011
Publisher: IEEE
Date: 05-2009
Publisher: Springer Berlin Heidelberg
Date: 2007
Publisher: IEEE
Date: 12-2018
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 2020
Publisher: IEEE
Date: 07-2009
Publisher: IEEE
Date: 03-2009
Publisher: IOP Publishing
Date: 11-2017
Publisher: IEEE
Date: 03-2009
Publisher: IOP Publishing
Date: 03-2017
Publisher: IEEE
Date: 05-2008
Publisher: IOP Publishing
Date: 20-12-2013
Publisher: IEEE
Date: 05-2015
Publisher: IEEE
Date: 05-2011
Publisher: IOP Publishing
Date: 20-12-2013
Publisher: IEEE
Date: 05-2015
Publisher: IEEE
Date: 08-2011
Publisher: EDP Sciences
Date: 2017
Publisher: InTech
Date: 29-08-2011
DOI: 10.5772/23432
Publisher: Elsevier BV
Date: 2012
Publisher: IEEE
Date: 06-2010
Publisher: IEEE
Date: 2005
Publisher: IEEE
Date: 09-2011
Publisher: IEEE
Date: 09-2012
Publisher: IEEE
Date: 06-2010
Publisher: IEEE
Date: 2009
Publisher: Public Library of Science (PLoS)
Date: 07-04-2015
Publisher: Springer Science and Business Media LLC
Date: 21-12-2015
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 05-2014
Publisher: IEEE
Date: 12-2015
Publisher: IEEE
Date: 11-2007
Publisher: Elsevier BV
Date: 2012
Publisher: IEEE
Date: 07-2013
Publisher: IEEE
Date: 2009
Publisher: IEEE
Date: 04-2010
Publisher: Springer Berlin Heidelberg
Date: 2013
Publisher: Elsevier BV
Date: 2017
DOI: 10.1016/J.ISATRA.2016.10.017
Abstract: This paper presents a fast terminal sliding mode based control design strategy for a class of uncertain underactuated nonlinear systems. Strategically, this development encompasses those electro-mechanical underactuated systems which can be transformed into the so-called regular form. The novelty of the proposed technique lies in the hierarchical development of a fast terminal sliding attractor design for the considered class. Having established sliding mode along the designed manifold, the close loop dynamics become finite time stable which, consequently, result in high precision. In addition, the adverse effects of the chattering phenomenon are reduced via strong reachability condition and the robustness of the system against uncertainties is confirmed theoretically. A simulation as well as experimental study of an inverted pendulum is presented to demonstrate the applicability of the proposed technique.
Publisher: Public Library of Science (PLoS)
Date: 17-02-2017
Publisher: IEEE
Date: 2001
Publisher: Springer Singapore
Date: 2019
Publisher: IOP Publishing
Date: 20-12-2013
Publisher: IOP Publishing
Date: 20-12-2013
Publisher: IEEE
Date: 05-2009
Publisher: IEEE
Date: 02-2015
Publisher: No publisher found
Date: 2015
DOI: 10.11113/JT.V77.6458
Publisher: The Scientific and Technological Research Council of Turkey (TUBITAK-ULAKBIM) - DIGITAL COMMONS JOURNALS
Date: 22-01-2019
DOI: 10.3906/ELK-1803-97
Publisher: IEEE
Date: 1999
Publisher: IEEE
Date: 07-2012
Publisher: Springer Science and Business Media LLC
Date: 10-2010
Publisher: IEEE
Date: 07-2012
Publisher: IOP Publishing
Date: 20-12-2013
Publisher: IEEE
Date: 05-2011
Publisher: Inderscience Publishers
Date: 2011
Publisher: IOP Publishing
Date: 11-2019
Publisher: IEEE
Date: 05-2015
Publisher: IEEE
Date: 05-2015
Publisher: WORLD SCIENTIFIC
Date: 29-07-2013
Publisher: IEEE
Date: 12-2010
Publisher: IEEE
Date: 12-2011
Publisher: IEEE
Date: 2006
Publisher: IEEE
Date: 09-2015
Publisher: IEEE
Date: 08-2010
Publisher: IEEE
Date: 06-2010
Publisher: IEEE
Date: 04-2011
Publisher: IOP Publishing
Date: 11-2018
Publisher: IEEE
Date: 05-2010
Publisher: Trans Tech Publications, Ltd.
Date: 03-2013
DOI: 10.4028/WWW.SCIENTIFIC.NET/AMM.313-314.559
Abstract: This paper presents the design of auto-stabilization control technique for a quadrotor system. Aquadrotor is a highly nonlinear and has to be stabilized by a suitable control technique. Therefore, the main focus of this research is to design an appropriate control algorithm that able to auto-stabilize the quadrotor at hover. The dynamic modeling of the quadrotor is described by sets of equations of motion that are derived based on the Newton-Euler formalism with the implementation of UKF for parameter identification and state estimation. The control strategy adopted includes feedback linearization coupled with Proportional-Derivative (PD) controller for the translational subsystem and backstepping based Proportional-Integral-Derivative (PID) controller for the rotational subsystem. It is developed in MATLAB/Simulink platform and is validated via real-time implementation. Both controllers give satisfactory simulation results, where acceptable peak of overshoot and small steady state errors are achieved. Experimentally, the throttle is controlled in manual mode while attitude angles are stabilized automatically. The simulation and experimental results show that the proposed controller is able to effectively stabillized the quadrotor.
Publisher: IEEE
Date: 2011
Publisher: IEEE
Date: 05-2009
Publisher: IEEE
Date: 03-2013
Location: No location found
No related grants have been discovered for Rini Akmeliawati.