Engineering Commons^™

K-Times Attribute-Based Anonymous Access Control For Cloud Computing, Joseph K. Liu, Tsz Hon Yuen, Man Ho Au, Xinyi Huang, Willy Susilo, Jianying Zhou

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we propose a new notion called k-times attribute-based anonymous access control, which is particularly designed for supporting cloud computing environment. In this new notion, a user can authenticate himself/herself to the cloud computing server anonymously. The server only knows the user acquires some required attributes, yet it does not know the identity of this user. In addition, we provide a k-times limit for anonymous access control. That is, the server may limit a particular set of users (i.e., those users with the same set of attribute) to access the system for a maximum k-times within a period …

Modeling And Inverse Feedforward Control For Conducting Polymer Actuators With Hysteresis, Xiangjiang Wang, Gursel Alici, Xiaobo Tan

Faculty of Engineering and Information Sciences - Papers: Part A

Conducting polymer actuators are biocompatible with a small footprint, and operate in air or liquid media under low actuation voltages. This makes them excellent actuators for macro- and micro-manipulation devices, however, their positioning ability or accuracy is adversely affected by their hysteresis non-linearity under open-loop control strategies. In this paper, we establish a hysteresis model for conducting polymer actuators, based on a rate-independent hysteresis model known as the Duhem model. The hysteresis model is experimentally identified and integrated with the linear dynamics of the actuator. This combined model is inverted to control the displacement of the tri-layer actuators considered in …

A Novel Approach For Ramp-Rate Control Of Solar Pv Using Energy Storage To Mitigate Output Fluctuations Caused By Cloud Passing, M J. E Alam, K M. Muttaqi, D Sutanto

Faculty of Engineering and Information Sciences - Papers: Part A

The variability of solar irradiance with a high ramp-rate, caused by cloud passing, can create fluctuation in the PV output. In a weak distribution grid with a high PV penetration, this can create significant voltage fluctuations. Energy storage devices are used to smooth out the fluctuation using traditional moving average control. However, moving average does not control the ramp-rate directly; rather the ramp-rate depends on previous values of PV output. This paper proposes a strategy where the ramp-rate of PV panel output is used to control the PV inverter ramp-rate to a desired level by deploying energy storage (which can …

Solar Pv And Battery Storage Integration Using A New Configuration Of A Three-Level Npc Inverter With Advanced Control Strategy, Hamid Teymour Ghasemabadi, Danny Soetanto, Kashem M. Muttaqi, Philip Ciufo

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, a novel configuration of a three-level neutral-point-clamped (NPC) inverter that can integrate solar photovoltaic (PV) with battery storage in a grid-connected system is proposed. The strength of the proposed topology lies in a novel, extended unbalance three-level vector modulation technique that can generate the correct ac voltage under unbalanced dc voltage conditions. This paper presents the design philosophy of the proposed configuration and the theoretical framework of the proposed modulation technique. A new control algorithm for the proposed system is also presented in order to control the power delivery between the solar PV, battery, and grid, which …

Online Voltage Control In Distribution Systems With Multiple Voltage Regulating Devices, Dothinka Ranamuka Rallage, Ashish Agalgaonkar, Kashem Muttaqi

Faculty of Engineering and Information Sciences - Papers: Part A

Voltage regulation in distribution systems is typically performed with the aid of multiple voltage regulating devices, such as on-load tap changer and step voltage regulators. These devices are conventionally tuned and locally coordinated using Volt/VAR optimization strategies in accordance with the time-graded operation. However, in case of distribution systems with distributed generation (DG), there could be a possibility of simultaneous responses of DG and multiple voltage regulators for correcting the target bus voltage, thereby resulting in operational conflicts. This paper proposes an online voltage control strategy for a realistic distribution system containing a synchronous machine-based renewable DG unit and other …

Optimal Design Of Semi Active Control For Adjacent Buildings Connected By Mr Damper Based On Integrated Fuzzy Logic And Multi-Objective Genetic Algorithm, Mehmet Uz, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part A

An optimal design strategy based on genetic algorithms (GA) is proposed for nonlinear hysteretic control devices that prevent pounding damage and achieve the best results in seismic response mitigation of two adjacent structures. An integrated fuzzy controller is used in order to provide the interactive relationships between damper forces and input voltages for MR dampers based on the modified Bouc-Wen model. Furthermore, Linear Quadratic Regulator (LQR) and H2/LQG (Linear Quadratic Gaussian) controllers based on clipped voltage law (CVL) are also used to compare the results obtained by fuzzy controller. This study employs the main objectives of the optimal design that …

Goaf Frictional Ignition And Its Control Measures In Underground Coal Mines, Gaofeng Wang, Ting Ren, Christopher David Cook

Faculty of Engineering and Information Sciences - Papers: Part A

Goaf Frictional Ignition (GFI) poses a serious threat to the safety of underground coal mines, and has caused many underground fires and catastrophic explosions. This paper examined occurrences of GFI incidents and the underlying mechanisms of ignition source and environment. Most of these incidents were attributed to rock on rock frictional ignition. The eventuation of frictional ignition relies on the presence of hot spots with enough incendive ignition energy, which requires a minimum threshold sliding distance and sliding velocity. The incendivity of the environment can be enhanced by the presence of liquid carbon hydrogen, the increase of virgin rock temperature, …

Control Of Conducting Polymer Actuators Without Physical Feedback: Simulated Feedback Control Approach With Particle Swarm Optimization, Xingcan Xiang, Rahim Mutlu, Gursel Alici, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part A

Conducting polymer actuators have shown significant potential in articulating micro instruments, manipulation devices, and robotics. However, implementing a feedback control strategy to enhance their positioning ability and accuracy in any application requires a feedback sensor, which is extremely large in size compared to the size of the actuators. Therefore, this paper proposes a new sensorless control scheme without the use of a position feedback sensor. With the help of the system identification technique and particle swarm optimization, the control scheme, which we call the simulated feedback control system, showed a satisfactory command tracking performance for the conducting polymer actuator's step …

An Adaptive Neuro Fuzzy Hybrid Control Strategy For A Semiactive Suspension With Magneto Rheological Damper, Pipit Wahyu Nugroho, Weihua Li, Haiping Du, Gursel Alici, Jian Yang

Faculty of Engineering and Information Sciences - Papers: Part A

The main function of a vehicle suspension system is to isolate the vehicle body from external excitation in order to improve passenger comfort and road holding and to stabilise its movement. This paper considers the implementation of an adaptive neuro fuzzy inference system (ANFIS) with a fuzzy hybrid control technique to control a quarter vehicle suspension system with a semiactive magneto rheological (MR) damper. A quarter car suspension model is set up with an MR damper and a semiactive controller consisting of a fuzzy hybrid skyhook-groundhook controller and an ANFIS model is also designed. The fuzzy hybrid controller is used …

Liquid Ink Deposition From An Atomic Force Microscope Tip: Deposition Monitoring And Control Of Feature Size, Cathal D. O'Connell, Michael J. Higgins, David Marusic, Simon E. Moulton, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

The controlled deposition of attoliter volumes of liquid inks may engender novel applications such as targeted drug delivery to single cells and localized delivery of chemical reagents at nanoscale dimensions. Although the deposition of small organic molecules from an atomic force microscope tip, known as dip-pen nanolithography (DPN), has been extensively studied, the deposition of liquid inks is little understood. In this work, we have used a set of model ink-substrate systems to develop an understanding of the deposition of viscous liquids using an unmodified AFM tip. First, the growth of dot size with increasing dwell time is characterized. The …

Design And Realization Of A Welding Oscillator, Muci̇z Özcan

Turkish Journal of Electrical Engineering and Computer Sciences

Welding is one of the most popular methods to combine metal pieces in manufacturing processes. Arc welding, among all welding techniques, is the most commonly used in manufacturing due to its cost and flexibility. During the manufacturing process, arc welding is either performed by an operator or by automatic tools such as welding oscillators. Using automatic tools has advantages over manual use, as the process will be faster, cheaper, and have less welding flaws. In this paper, a homemade welding oscillator and the method to manufacture it are presented. The presented welding oscillator can be manufactured for a very low …

Development Of An Optical Sensor For Real-Time Weed Detection Using Laser Based Spectroscopy, Arie Jacobus Paap

Theses: Doctorates and Masters

The management of weeds in agriculture is a time consuming and expensive activity, including in Australia where the predominant strategy is blanket spraying of herbicides. This approach wastes herbicide by applying it in areas where there are no weeds. Discrimination of different plant species can be performed based on the spectral reflectance of the leaves. This thesis describes the development of a sensor for automatic spot spraying of weeds within crop rows. The sensor records the relative intensity of reflected light in three narrow wavebands using lasers as an illumination source.

A prototype weed sensor which had been previously developed …

Parameter Identification And Fault Detection For Reliable Control Of Permanent Magnet Motors, Dusan Vukosav Progovac

Wayne State University Dissertations

The objective of this dissertation is to develop new fault detection, identification, estimation and control algorithms that will be used to detect winding stator fault, identify the motor parameters and optimally control machine during faulty condition. Quality or proposed algorithms for Fault detection, parameter identification and control under faulty condition will validated through analytical study (Cramer-Rao bound) and simulation. Simulation will be performed for three most applied control schemes: Proportional-Integral-Derivative (PID), Direct Torque Control (DTC) and Field Oriented Control (FOC) for Permanent Magnet Machines. New detection schemes forfault detection, isolation and machine parameter identification are presented and analyzed. Different control …

A Tutorial On Learning Human Welder's Behavior: Sensing, Modeling, And Control, Y. K. Liu, W. J. Zhang, Yu Ming Zhang

Electrical and Computer Engineering Faculty Publications

Human welder's experiences and skills are critical for producing quality welds in manual GTAW process. Learning human welder's behavior can help develop next generation intelligent welding machines and train welders faster. In this tutorial paper, various aspects of mechanizing the welder's intelligence are surveyed, including sensing of the weld pool, modeling of the welder's adjustments and this model-based control approach. Specifically, different sensing methods of the weld pool are reviewed and a novel 3D vision-based sensing system developed at University of Kentucky is introduced. Characterization of the weld pool is performed and human intelligent model is constructed, including an extensive …

Situation Awareness And Maritime Traffic: Having Awareness Or Being In Control?, Fulko Van Westrenen, Gesa Praetorius

Gesa Praetorius

Situation awareness (SA) is generally seen as a mental representation of the system state, an objective measure of the ‘situation out there’. In this article, the authors make an argument that SA can only have a meaning in relation to the task of the user and characteristics of the system. This will be argued with the help of a specific environment: vessel traffic monitoring. The long-time constants and the complex constraints imposed on the ship require that the operator monitoring the traffic has a good SA: the operator must make long-term predictions about possible traffic developments. For this, being in …

Wind Power Electric Systems: Modelization, Control And Optimization, Djamila Rekioua Pr

REKIOUA Djamila Dr

The book is organized through seven chapters as follows: • Chapter 1 is intended as an introduction to the subject. It defines the wind process, introduces the main meteorological elements, the wind velocity, and presents an overview of wind systems (stand-alone systems and grid connected systems). This chapter includes also pre-sizing and maintenance of wind systems. • Chapter 2 focuses on wind energy conversion and power electronics modeling. The different structures of converters used in wind systems are presented. Some applications are given under Matlab/Simulink. • In Chapter 3, a detailed review on the most used algorithms to track the …