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Articles 1 - 15 of 15
Full-Text Articles in Physical Sciences and Mathematics
Emotional States Control For On-Line Game Avatars, Ce Zhan, Wanqing Li, Farzad Safaei, Philip Ogunbona
Emotional States Control For On-Line Game Avatars, Ce Zhan, Wanqing Li, Farzad Safaei, Philip Ogunbona
Associate Professor Wanqing Li
Although detailed animation has already been achieved in a number of Multi-player On-line Games (MOGs), players have to use text commands to control emotional states of avatars. Some systems have been proposed to implement a real-time automatic system facial expression recognition of players. Such systems can then be used to control avatars emotional states by driving the MOG's "animation engine" instead of text commands. Some of the challenges of such systems is the ability to detect and recognize facial components from low spatial resolution face images. In this paper a system based on an improved face detection method of Viola …
Predicting Avian Distributions To Evaluate Spatiotemporal Overlap With Locust Control Operations In Eastern Australia, Judit K. Szabo, Pamela J. Davy, Michael Hooper, Lee Astheimer
Predicting Avian Distributions To Evaluate Spatiotemporal Overlap With Locust Control Operations In Eastern Australia, Judit K. Szabo, Pamela J. Davy, Michael Hooper, Lee Astheimer
Dr Pamela Davy
Locusts and grasshoppers cause considerable economic damage to agriculture worldwide. The Australian Plague Locust Commission uses multiple pesticides to control locusts in eastern Australia. Avian exposure to agricultural pesticides is of conservation concern, especially in the case of rare and threatened species. The aim of this study was to evaluate the probability of pesticide exposure of native avian species during operational locust control based on knowledge of species occurrence in areas and times of application. Using presence-absence data provided by the Birds Australia Atlas for 1998 to 2002, we developed a series of generalized linear models to predict avian occurrences …
New Constructions Of Osbe Schemes And Their Applications In Oblivious Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan
New Constructions Of Osbe Schemes And Their Applications In Oblivious Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan
Dr Jun Yan
Oblivious signature-based envelope (OSBE) schemes have demonstrated their potential applications in the protection of users privacy and rights. In an OSBE protocol, an encrypted message can only be decrypted by the receiver who holds a valid signature on a public message, while the sender (encrypter) does not know whether the receiver has the signature or not. Our major contributions in this work lie in the following aspects. We improve the notion of OSBE so that a valid credential holder cannot share his/her credential with other users (i. e., all-or-nothing non-transferability). We clarify the relationship between one-round OSBE and identity-based encryption …
Efficient Oblivious Transfers With Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan
Efficient Oblivious Transfers With Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan
Dr Jun Yan
Oblivious transfer (OT) is a protocol where a receiver can obtain t-out-of-n services from the sender without releasing anything about his choices. OT can be used to protect user’s privacy. In principle, any user can interact with a server to request some services. This might allow some undesirable users to obtain services from the server. How to ensure that only the authorized receivers can obtain services obliviously is a daunting task. In this paper, we introduce oblivious signature based-on envelope (OSBE) to OT and propose two novel OT schemes, which only allow the legitimate receivers to obtain services obliviously. The …
New Constructions Of Osbe Schemes And Their Applications In Oblivious Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan
New Constructions Of Osbe Schemes And Their Applications In Oblivious Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan
Professor Willy Susilo
Oblivious signature-based envelope (OSBE) schemes have demonstrated their potential applications in the protection of users privacy and rights. In an OSBE protocol, an encrypted message can only be decrypted by the receiver who holds a valid signature on a public message, while the sender (encrypter) does not know whether the receiver has the signature or not. Our major contributions in this work lie in the following aspects. We improve the notion of OSBE so that a valid credential holder cannot share his/her credential with other users (i. e., all-or-nothing non-transferability). We clarify the relationship between one-round OSBE and identity-based encryption …
Control Of Energy Storage Interface With A Bidirectional Converter For Photovoltaic Systems, K.N Hasan, M.E Haque, Michael Negnevitsky, Kashem Muttaqi
Control Of Energy Storage Interface With A Bidirectional Converter For Photovoltaic Systems, K.N Hasan, M.E Haque, Michael Negnevitsky, Kashem Muttaqi
Associate Professor Kashem Muttaqi
Efficient energy storage is one of the greatest concerns for renewable power generation. This paper focuses on the control of a battery management system (BMS) for photovoltaic (PV) applications with a high efficiency bidirectional converter. The proposed BMS control strategy utilizes the dc bus power and battery state of charge (SOC) for the charging and discharging of the battery with a bidirectional converter. The bidirectional converter includes fewer components and switches, has less switching losses with zero voltage switching, and has high gain buck-boost operations. A new control algorithm of charging-discharging control for the battery storage system is proposed. The …
Output Quality Evaluation Of Photovoltaic Systems With Different Current Control Methods Of Switch-Mode Converters, K. N. Hasan, Md Enamul Haque, Michael Negnevitsky, Kashem Muttaqi
Output Quality Evaluation Of Photovoltaic Systems With Different Current Control Methods Of Switch-Mode Converters, K. N. Hasan, Md Enamul Haque, Michael Negnevitsky, Kashem Muttaqi
Associate Professor Kashem Muttaqi
This paper presents a comparative assessment of the current control methods (CCM) of switch-mode converters for photovoltaic (PV) applications. In this paper, average current control, current programmed control, hysteresis current control and nonlinear carrier control methods are addressed considering input fluctuations and load variations for PV systems. Dynamic responses of PV systems are investigated and harmonic analysis is performed. Performances of the above current controllers are examined through simulation and the results are presented. The results show that the selection of different current control techniques depends on the working conditions and the area of applications.
Modelling Of Hydraulic Governor-Turbine For Control Stabilisation, Michael Negnevitsky, Kashem Muttaqi, Yin Chin Choo
Modelling Of Hydraulic Governor-Turbine For Control Stabilisation, Michael Negnevitsky, Kashem Muttaqi, Yin Chin Choo
Associate Professor Kashem Muttaqi
Power system performance is affected by dynamic characteristics of hydraulic governor-turbines during and following any disturbance, such as occurrence of a fault, loss of a transmission line or a rapid change of load. Accurate modelling of hydraulic governor-turbines is essential to characterise and diagnose the system response during an emergency. In this article, both detailed and simplified hydraulic systems governed by proportional-integral-derivative and proportional-integral controllers are modelled. This article examines their transient responses to disturbances through simulation in Matlab/Simulink. The article also investigates the dynamic performance of an isolated hydraulic system through evaluating stability margins, eigenvalues, root loci and frequency …
New Constructions Of Osbe Schemes And Their Applications In Oblivious Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan
New Constructions Of Osbe Schemes And Their Applications In Oblivious Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan
Professor Yi Mu
Oblivious signature-based envelope (OSBE) schemes have demonstrated their potential applications in the protection of users privacy and rights. In an OSBE protocol, an encrypted message can only be decrypted by the receiver who holds a valid signature on a public message, while the sender (encrypter) does not know whether the receiver has the signature or not. Our major contributions in this work lie in the following aspects. We improve the notion of OSBE so that a valid credential holder cannot share his/her credential with other users (i. e., all-or-nothing non-transferability). We clarify the relationship between one-round OSBE and identity-based encryption …
Efficient Oblivious Transfers With Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan
Efficient Oblivious Transfers With Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan
Professor Yi Mu
Oblivious transfer (OT) is a protocol where a receiver can obtain t-out-of-n services from the sender without releasing anything about his choices. OT can be used to protect user’s privacy. In principle, any user can interact with a server to request some services. This might allow some undesirable users to obtain services from the server. How to ensure that only the authorized receivers can obtain services obliviously is a daunting task. In this paper, we introduce oblivious signature based-on envelope (OSBE) to OT and propose two novel OT schemes, which only allow the legitimate receivers to obtain services obliviously. The …
T-S Fuzzy H Tracking Control Of Input Delayed Robotic Manipulators, Haiping Du, Weihua Li
T-S Fuzzy H Tracking Control Of Input Delayed Robotic Manipulators, Haiping Du, Weihua Li
Dr Haiping Du
Time delays are often encountered by practical control systems while they are acquiring, processing, communicating, and sending signals. Time delays may affect the system stability and degrade the control system performance if they are not properly dealt with. Taking the classical robot control problem as an example, the significant effect of time delay on the closed-loop system stability has been highlighted in the bilateral teleoperation, where the communication delay transmitted through a network medium has been received widespread attention and different approaches have been proposed to address this problem (Hokayem and Spong, 2006). In addition, examples like processing delays in …
Fuzzy Stability Control Of Robotic Manipulator With Input Delays, Haiping Du, Fazel Naghdy, David A. Stirling
Fuzzy Stability Control Of Robotic Manipulator With Input Delays, Haiping Du, Fazel Naghdy, David A. Stirling
Dr Haiping Du
This paper studies the stabilisation control problem of a robotic manipulator with input delays. To deal with the highly nonlinear dynamics of a robotic manipulator, the model-based Takagi-Sugeno (T-S) fuzzy control strategy is applied. With representing the nonlinear robotic manipulator model as a T-S fuzzy model, sufficient conditions for designing a controller such that the system is stabilised with given decay rate are derived by constructing a less conservative Lyapunov-Krasovskii functional and using a tighter bounding technology for cross terms and the free weighting matrix approach. With appropriate derivation, all the required conditions are expressed as linear matrix inequalities (LMIs). …
Fuzzy Control For Nonlinear Uncertain Electrohydraulic Active Suspensions With Input Constraint, Haiping Du, Nong Zhang
Fuzzy Control For Nonlinear Uncertain Electrohydraulic Active Suspensions With Input Constraint, Haiping Du, Nong Zhang
Dr Haiping Du
This paper presents a Takagi-Sugeno (T-S) model-based fuzzy control design approach for electrohydraulic active vehicle suspensions considering nonlinear dynamics of the actuator, sprung mass variation, and constraints on the control input. The T-S fuzzy model is first applied to represent the nonlinear uncertain electrohydraulic suspension. Then, a fuzzy state feedback controller is designed for the obtained T-S fuzzy model with optimized H infin performance for ride comfort by using the parallel-distributed compensation (PDC) scheme. The sufficient conditions for the existence of such a controller are derived in terms of linear matrix inequalities (LMIs). Numerical simulations on a full-car suspension model …
Emotional States Control For On-Line Game Avatars, Ce Zhan, Wanqing Li, Farzad Safaei, Philip Ogunbona
Emotional States Control For On-Line Game Avatars, Ce Zhan, Wanqing Li, Farzad Safaei, Philip Ogunbona
Professor Philip Ogunbona
Although detailed animation has already been achieved in a number of Multi-player On-line Games (MOGs), players have to use text commands to control emotional states of avatars. Some systems have been proposed to implement a real-time automatic system facial expression recognition of players. Such systems can then be used to control avatars emotional states by driving the MOG's "animation engine" instead of text commands. Some of the challenges of such systems is the ability to detect and recognize facial components from low spatial resolution face images. In this paper a system based on an improved face detection method of Viola …
Extrinsic Control Of The Exchange Bias, Christian Binek
Extrinsic Control Of The Exchange Bias, Christian Binek
Christian Binek
A new control mechanism for the exchange bias effect in magnetic heterostructures is proposed. It takes advantage of the magnetoelectric effect which takes place in the antiferromagnetic pinning layer. In contrast with the pioneering AC measurements of the magnetoelectric effect, we investigate the magnetic response of the prototypical magnetoelectric compound Cr2O3 on static electric fields. The linear dependence of the magnetic moment on the applied axial electric field and the temperature dependence of the corresponding slopes αshort parallel are measured by DC SQUID magnetometry. The contribution of the field-induced surface magnetization and its impact on the exchange bias effect is …