13,008 research outputs found

    Fuzzy logic power system stabiliser in multi-machine stability studies.

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    Thesis (M.Sc. Eng.)-University of Natal, Durban, 2003.Conventional power system stabilisers (PSS) are designed to eliminate poorly damped, low frequency power oscillations that occur between remote generating pools or power stations, due to different types and settings of the automatic voltage regulators at different power stations. The supplementary control of the PSS is exerted on the power system through a generator's excitation system to which the PSS is attached. In order to design these conventional power system stabilisers , requires accurate system data and an in-depth knowledge of classical control theory. This thesis investigates the use of an intelligent, non-linear PSS that utilises fuzzy logic techniques. Others have proposed the concept of such a PSS, since it does not require accurate system data. This thesis describes the basic aspects of power system stability . Thereafter the methods of modelling synchronous machines in a multi-machine power system are presented. The sample power system being studied and the simulation packages used in the investigations are introduced and the methods involved to design and tune a conventional power system stabiliser using classical control theory and design methods proposed by others, are discussed. The general concept of fuzzy logic is introduced and the application of fuzzy logic techniques to controller design is explained. Using the principles of fuzzy logic controller design, a fuzzy logic power system stabiliser utilising 9 rules is designed and tuned for the multi-machine power system under investigation. The fuzzy logic stabiliser is then applied to a synchronous motor in a pump storage scheme. Previous work has applied fuzzy logic stabilisers only to synchronous generators . To further compare the performance of the 9 rule fuzzy stabiliser, a 49 rule stabiliser developed by other researchers, and adapted to operate on the synchronous motor, is evaluated. Computer simulated results of each of the stabiliser's performances are presented. The results of the 9 rule fuzzy stabiliser are compared with the performance of a conventional linear stabiliser as well as with a 49 rule fuzzy stabiliser. The robustness properties of the fuzzy stabilisers are evaluated. The results further prove that with proper membership function selection, a simple fuzzy stabiliser that demands very little computational overheads can be achieved to provide adequate system damping

    Fuzzy-logic-based control, filtering, and fault detection for networked systems: A Survey

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    This paper is concerned with the overview of the recent progress in fuzzy-logic-based filtering, control, and fault detection problems. First, the network technologies are introduced, the networked control systems are categorized from the aspects of fieldbuses and industrial Ethernets, the necessity of utilizing the fuzzy logic is justified, and the network-induced phenomena are discussed. Then, the fuzzy logic control strategies are reviewed in great detail. Special attention is given to the thorough examination on the latest results for fuzzy PID control, fuzzy adaptive control, and fuzzy tracking control problems. Furthermore, recent advances on the fuzzy-logic-based filtering and fault detection problems are reviewed. Finally, conclusions are given and some possible future research directions are pointed out, for example, topics on two-dimensional networked systems, wireless networked control systems, Quality-of-Service (QoS) of networked systems, and fuzzy access control in open networked systems.This work was supported in part by the National Natural Science Foundation of China under Grants 61329301, 61374039, 61473163, and 61374127, the Hujiang Foundation of China under Grants C14002 andD15009, the Engineering and Physical Sciences Research Council (EPSRC) of the UK, the Royal Society of the UK, and the Alexander von Humboldt Foundation of Germany

    Impact of Embedded Carbon Fiber Heating Panel on the Structural/Mechanical Performance of Roadway Pavement

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    INE/AUTC 12.3

    Evolution engine technology in exhaust gas recirculation for heavy-duty diesel engine

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    In this present year, engineers have been researching and inventing to get the optimum of less emission in every vehicle for a better environmental friendly. Diesel engines are known reusing of the exhaust gas in order to reduce the exhaust emissions such as NOx that contribute high factors in the pollution. In this paper, we have conducted a study that EGR instalment in the vehicle can be good as it helps to prevent highly amount of toxic gas formation, which NOx level can be lowered. But applying the EGR it can lead to more cooling and more space which will affect in terms of the costing. Throughout the research, fuelling in the engine affects the EGR producing less emission. Other than that, it contributes to the less of performance efficiency when vehicle load is less

    An improved artificial dendrite cell algorithm for abnormal signal detection

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    In dendrite cell algorithm (DCA), the abnormality of a data point is determined by comparing the multi-context antigen value (MCAV) with anomaly threshold. The limitation of the existing threshold is that the value needs to be determined before mining based on previous information and the existing MCAV is inefficient when exposed to extreme values. This causes the DCA fails to detect new data points if the pattern has distinct behavior from previous information and affects detection accuracy. This paper proposed an improved anomaly threshold solution for DCA using the statistical cumulative sum (CUSUM) with the aim to improve its detection capability. In the proposed approach, the MCAV were normalized with upper CUSUM and the new anomaly threshold was calculated during run time by considering the acceptance value and min MCAV. From the experiments towards 12 benchmark and two outbreak datasets, the improved DCA is proven to have a better detection result than its previous version in terms of sensitivity, specificity, false detection rate and accuracy

    Regression between headmaster leadership, task load and job satisfaction of special education integration program teacher

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    Managing school is a daunting task for a headmaster. This responsibility is exacerbated when it involves the Special Education Integration Program (SEIP). This situation requires appropriate and effective leadership in addressing some of the issues that are currently taking place at SEIP such as task load and job satisfaction. This study aimed to identify the influence of headmaster leadership on task load and teacher job satisfaction at SEIP. This quantitative study was conducted by distributing 400 sets of randomized questionnaires to SEIP teachers across Malaysia through google form. The data obtained were then analyzed using Structural Equation Modeling (SEM) and AMOS software. The results show that there is a significant positive effect on the leadership of the headmaster and the task load of the teacher. Likewise, the construct of task load and teacher job satisfaction has a significant positive effect. However, for the construct of headmaster leadership and teacher job satisfaction, there was no significant positive relationship. This finding is very important as a reference to the school administration re-evaluating their leadership so as not to burden SEIP teachers and to give them job satisfaction. In addition, the findings of this study can also serve as a guide for SEIP teachers to increase awareness of the importance of managing their tasks. This study also focused on education leadership in general and more specifically on special education leadership

    A High Performance Fuzzy Logic Architecture for UAV Decision Making

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    The majority of Unmanned Aerial Vehicles (UAVs) in operation today are not truly autonomous, but are instead reliant on a remote human pilot. A high degree of autonomy can provide many advantages in terms of cost, operational resources and safety. However, one of the challenges involved in achieving autonomy is that of replicating the reasoning and decision making capabilities of a human pilot. One candidate method for providing this decision making capability is fuzzy logic. In this role, the fuzzy system must satisfy real-time constraints, process large quantities of data and relate to large knowledge bases. Consequently, there is a need for a generic, high performance fuzzy computation platform for UAV applications. Based on Lees’ [1] original work, a high performance fuzzy processing architecture, implemented in Field Programmable Gate Arrays (FPGAs), has been developed and is shown to outclass the performance of existing fuzzy processors
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