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Improved Field-Oriented Control for PWM Multi-level inverter-Fed Induction Motor Drives
This paper proposes a new approach to ensure the torque decoupled to the rotor flux of an induction machine based on the Field Oriented Control (FOC). The suggested method consists of inserting into the conventional d-q synchronous current controller, coupling terms of motor and multi-level inverter models. Making, the dynamic response of stator current components decoupled as well as the rotor flux and torque. In this paper, the mathematic model of an induction motor and multi-level inverter are first derived. Then, the synchronous current controller and modulation strategy for high power inverters are investigated. Finally, the validation through implementation and simulation of a 4.16 kV electric drive with MATLAB/Simulink and SimPowerSystems is performed. The model simulated in this paper includes an induction motor, nine-level cascaded H-bridge inverter and a carrier based space vector pulse-width-modulation.The results of the simulations of each method has been recorded and the comparison results reveal that the proposed method effectively maintains the rotor flux decoupled to the torque
Selective Colligation and Selective Scrambling for Privacy Preservation in Data Mining
The work is to enhance the time efficiency in retrieving the data from enormous bank database. The major drawback in retrieving data from large databases is time delay. This time hindrance is owed as the already existing method (SVM), Abstract Data Type (ADT) tree pursues some elongated Sequential steps. These techniques takes additional size and with a reduction of speed in training and testing. Another major negative aspect of these techniques is its Algorithmic complexity. The classification algorithms have five categories. They are ID3, k-nearest neighbour, Decision tree, ANN, and Naïve Bayes algorithm. To triumph over the drawbacks in SVM techniques, we worn a technique called Naïve Bayes Classification (NBC) Algorithm that works in parallel manner rather than sequential manner. For further enhancement we commenced a Naïve Bayes updatable algorithm which is the advanced version of Naïve Bayes classification algorithm. Thus the proposed technique Naïve bayes algorithm ensures that miner can mine more efficiently from the enormous database
Evolution of Precision Agriculture Computing towards Sustainable Oil Palm Industry
Precision technology elements have not been implemented yet into the sustainable oil palm industry because the knowledge and technology gap. To resolve the gaps, promote sustainability and integrate the technologies, Oil Palm Management System (OPAMS) was introduced. The precision technologies in OPAMS comprises of Geographical Information System (GIS), Global Positioning System (GPS), remote sensing and yield monitoring. A phase by phase System Development Life Cycle (SDLC) methodology was used to generate the said system with feedbacks from oil palm planters as the inputs for OPAMS’s key features. OPAMS ultimately aims to increase the awareness of the industry on the benefits of utilizing technology to improve plantation performances, increase business and environmental sustainability
Task Scheduling in Heterogeneous Multiprocessor Environments – An Efficient ACO-Based Approach
In heterogeneous computing environments, finding optimized solutions continues to be one of the most important and yet, very challenging problems. Task scheduling in such environments is NP-hard, so efficient mapping of tasks to the processors remains one of the most critical issues to be tackled. For several types of applications, the task scheduling problem is crucial, and across the literature, a number of algorithms with several different approaches have been proposed. One such effective approach is known as Ant Colony Optimization (ACO). This popular optimization technique is inspired by the capabilities of ant colonies to find the shortest paths between their nests and food sources. Consequently, we propose an ACO-based algorithm, called rACS, as a solution to the task scheduling problem. Our algorithm utilizes pheromone and a priority-based heuristic, known as the upward rank value, as well as an insertion-based policy and a pheromone aging mechanism to guide the ants to high quality solutions. To evaluate the performance of our algorithm, we compared our algorithm with the ACS algorithm and the ACO-TMS algorithm using randomly generated directed acyclic graphs (DAGs). The simulation results indicated that our algorithm experienced comparable or even better performance, than the selected algorithms
A Study of Some Iterative Methods for Solving Fuzzy Volterra-Fredholm Integral Equations
This paper mainly focuses on the recent advances in the some approximated methods for solving fuzzy Volterra-Fredholm integral equations, namely, Adomian decomposition method, variational iteration method and homotopy analysis method. We converted fuzzy Volterra-Fredholm integral equation to a system of Volterra-Fredholm integral equation in crisp case. The approximated methods using to find the approximate solutions of this system and hence obtain an approximation for the fuzzy solution of the fuzzy Volterra-Fredholm integral equation. To assess the accuracy of each method, algorithms with Mathematica 6 according is used. Also, some numerical examples are included to demonstrate the validity and applicabilityof the proposed techniques.This paper mainly focuses on the recent advances in the some approximated methods for solvingfuzzy Volterra-Fredholm integral equations, namely, Adomian decomposition method, variational iterationmethod and homotopy analysis method. We converted fuzzy Volterra-Fredholm integral equation to asystem of Volterra-Fredholm integral equation in crisp case. The approximated methods using to find theapproximate solutions of this system and hence obtain an approximation for the fuzzy solution of the fuzzyVolterra-Fredholm integral equation. To assess the accuracy of each method, algorithms with Mathematica 6according is used. Also, some numerical examples are included to demonstrate the validity and applicabilityof the proposed techniques
A Comparative Study of Phase Offset Disposition Sinusoidal Pulse Width Modulation (POD-SPWM) and Symmetrical Pulse Width Modulation Switching Techiques for Generalized Current Source Multilevel Inverter(MCSI)
This paper presents a comparison between two switching techniques namely Phase Offset Disposition Sinusoidal PWM (POD-SPWM) and Symmetrical PWM switching for a generalized current source multilevel inverter (MCSI) topology. One of the advantages of MCSI is it can reduce the total harmonic distortion (THD) at the output load current with a sinusoidal current waveform. In this paper, the generalized MCSI with the different levels has been developed with Matlab@simulation software in order to study the performance of the two switching schemes for the operation of the MCSI. From the simulation results, POD-SPWM switching technique can give better THD results compare to symmetrical switching technique
Query Processing for Time Efficient Data Retrieval
In database management system (DBMS) retrieving data through structure query language is an essential aspect to find better execution plan for performance. In this paper, we incorporated database objects to optimize query execution time and its cost by vanishing poorly SQL statements. We proposed a method of evolving and inserting database constraints as database objects embedded with queries either to add them for the sake of transactions required by user to detect those queries for the betterment of performance. We took analysis on several databases while processing queries itself and assimilate real time database workload with the bunch of transactions are invoked in comparison with tuning approaches. These database objects are coded in procedural language environment pertaining rules to make it worth and are merged into queries offering improved execution plan
Framework and Implementation of Marine Dumping Area’s Monitoring System Based on GPRS
An installed based astute ready framework is contrived for the best possible checking and support of the waste. This structure turns away the unpredictable cleaning of the dustbins by sending alarms to the concerned individual at general interims. It additionally enhances the framework by also supporting the status of cleaning progressively and measure the execution of the group. Accordingly, this structure proves to be useful as a praiseworthy arrangement in natural support. Notwithstanding this, it additionally helps to lessen the requirement for high human intercession in junk support of the district and contamination observing framework
Implementation of Antiestablishment Wire Fault Sensing Using CC3200
Underground cables are inclined to faults because of underground conditions. Detecting particular fault area in the underground cable is a tedious one for that the whole line is to be dug check and settle issues. The proposed method using IoT identifies the correct fault position that makes repairing work simple. The professional domain workers identify the fault area sometimes they also are not able to predict the fault location. Determining fault in the cable itself take lots of time, cash and endeavours and furthermore permit to service underground links speedier. An excellent Wi-Fi featured ARM Cortex-M4 microcontroller is utilised to implement the system. This device offers a total, ease, practical and easy to use method for continuous checking. The fault is acknowledged with the help of sensors placed over the cable. The cell phone application furnishes with a GUI to screen the information from a remote area. The cloud server act as the centre man between the hardware device and the cell phone application dealing with the data movement
Assessment Analytic Theoretical Framework Based on Learners’ Continuous Learning Improvement
Currently, university students are required to follow stringent curriculum structure regardless of their performance. Personalized learning is not being offered resulting the whole cohort must compy to a customized fixed curriculum design. This is because the designed curriculum does not take into account different students’ attainment. Furthermore, there is a mismatched between supply and demand of graduates’ skill sets to fulfil the requirement of industry. Due to these issues, employers face difficulties in finding suitable high-skilled worker which contributes to large number of unemployed graduates. Thus, a systematic intervention of students’ learning process is essential to construct informed and strategic responses in order to manage challenges and minimize skill mismatch, at the same time providing adequate fundamental knowledge. In this paper, an assessment analytics framework is proposed based on automated extracted skill sets from curriculum documents and individual performance to recommend adaptive learners’ learning system (ALLS). By preparing the graduates with the required industry skill sets, the graduates’ unemployment rate is envisaged to reduce