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Text Mining for Pest and Disease Identification on Rice Farming with Interactive Text Messaging
No full textTo overcome pests and diseases of rice farming, farmers always rely on information and knowledge from agricultural experts for decision making. The problem is that experts are not always available when the farmers need and the cost is quite high. Pests and diseases elimination is hard to be done individually since the farmers are lack of knowledge about the pest types that attack the rice fields. The objective of this study is to build a knowledge-based system that can identify pests and diseases interactively based on the information that has been told by the farmers using SMS communication services. The system can provide a convenience way to the farmers in delivering pests and disease problem information using a natural language. The text mining method performs tokenizing, filtering and porter stemming that used to extract important information sent by a SMS service. The method of Jaccard Similarity Coefficient (JSC) was used to calculate similarities of each pest and disease based on symptoms that are sent by the farmers through SMS. The corpus database used in this study consists of 28.526 root words, 1.309 stop words and 180 words list. Pest and disease database reference in this study was obtained from the Ministry of Agriculture and Fisher (MAF) Timor-Leste. The result of the experiment shows that the system is able to identify the symptoms based on the keywords identified with the accuracy of 81%. The result of pest and disease identification has the accuracy of 86%
R&D of Photovoltaic Thermal (PVT) Systems: an Overview
No full textPhotovoltaic thermal (PVT), which is the popular technology for harvesting solar energy, receive solar energy and convert it into electrical and thermal energy simultaneously. In this review, design, heat transfer, energy modelling and performance analysis of PVT systems are presented. Four types of PVT systems base on heat transfer medium; air-based PVT system, water-based PVT system, the combination of water/air-based PVT system, and nanofluid-based PVT system are presented. In addition, major finding on energy and exergy analysis of PVT systems are summarized.
Appropriate Switching State Selection to Avoid Sapacitor Imbalance in Five-Level NPC
No full textAn intrinsic problem with neutral point clamped (NPC) multilevel inverters (MLI) is unbalance of capacitor voltage. There are many mitigation techniques well established in the literature to balance the neutral point voltage for 3-level inverter. These techniques employ either Carrier based pulse width modulation (CBPWM), Space vector pulse width modulation (SVPWM) or hybrid of both the PWM techniques. Balancing becomes complicated as the level of the inverter increases due to addition of capacitor junctions. The imbalance in capacitor voltages may cause uneven voltage distribution among switching devices and sometimes may cause failure. It also increases harmonic content in its output waveform. This paper develops new modulation scheme for balancing capacitor voltages for Five-level inverter .The scheme is a hybrid PWM which is a combination of both CBPWM and SVPWM techniques. As per this scheme CBPWM is applied to meet the load demand and at the zero crossings of the reference signal, CBPWM is blocked and for one carrier cycle. During this SVPWM is applied with appropriate switching state selection to neutralize the imbalance in capacitor voltage
SLIC Superpixel Based Self Organizing Maps Algorithm for Segmentation of Microarray Images
No full textWe can find the simultaneous monitoring of thousands of genes in parallel Microarray technology. As per these measurements, microarray technology have proven powerful in gene expression profiling for discovering new types of diseases and for predicting the type of a disease. Gridding, Intensity extraction, Enhancement and Segmentation are important steps in microarray image analysis. This paper gives simple linear iterative clustering (SLIC) based self organizing maps (SOM) algorithm for segmentation of microarray image. The clusters of pixels which share similar features are called Superpixels, thus they can be used as mid-level units to decrease the computational cost in many vision applications. The proposed algorithm utilizes superpixels as clustering objects instead of pixels. The qualitative and quantitative analysis shows that the proposed method produces better segmentation quality than k-means, fuzzy c-means and self organizing maps clustering methods
Framework to Avoid Similarity Attack in Big Streaming Data
No full textThe existing methods for privacy preservation are available in variety of fields like social media, stock market, sentiment analysis, electronic health applications. The electronic health dynamic stream data is available in large quantity. Such large volume stream data is processed using delay free anonymization framework. Scalable privacy preserving techniques are required to satisfy the needs of processing large dynamic stream data. In this paper privacy preserving technique which can avoid similarity attack in big streaming data is proposed in distributed environment. It can process the data in parallel to reduce the anonymization delay. In this paper the replacement technique is used for avoiding similarity attack. Late validation technique is used to reduce information loss. The application of this method is in medical diagnosis, e-health applications, health data processing at third part
Fuzzy Model Predictive Controller for Artificial Pancreas
No full textThis work consists on new tuning of Model Predictive Controllers using Fuzzy Logic method. Tree relevant parameters are automatically adjusted the prediction horizon Np, the input weight R and the output weight Q. The proposed controller is implemented in an Artificial Pancreas and tested under realistic conditions in a commercial platform of simulation. The result of the simulations revealed the success of such a method to improve the controller’s performances compared to the previous ones
Comparison between PI and PR Current Controllers of a Grid- Connected Photovoltaic System Under Load Variation
No full textThis paper presents a current control technique for a three-phase grid-connected DC /AC inverter which is used in photovoltaic systems. A Proportional-Resonant (PR) controller is used for replacing the conventional Proportional-Integral (PI) controller in this system. By comparison with the conventional PI control method, the PR control can introduce an infinite gain at the fundamental frequency and hence can achieve zero steady-state error. The proposed model is based on two control loops: the first control loop regulates DC link voltage and the second one is used to keep the injected current to the grid in phase with the voltage by means of a Phase Locked Loop (PLL) in order to achieve a unit power factor and to adjust the output power as required. In order to examine the effectiveness of the suggested control, a simulation using the Matlab/Simulink software has been done and it’s concluded from the simulation results that the presented control by using the PR controller can be able to maintain maximum active power and to keep always a unity power factor despite variation load
An Analysis of Virtual Direct Power Control of Three-Phase AC-DC Converter
No full textThis paper presents an analysis of virtual-flux direct power control (VFDPC) technique for the three-phase pulse width modulation (PWM) ac-dc converter. The proposed VFDPC is developed by assuming the grid voltage and converter line filters quantities are related to a virtual three-phase ac motor. The controller works with less number of sensors by eliminating the voltage sensors used for measuring the three-phase grid voltage. The grid virtual flux which is proportional to the grid voltage will be estimated from the information of converter switching states, line current, and dc-link output voltage. Several analyses are performed in order to study the steady state and dynamic performance of the converter, particularly during the load and DC voltage output reference variations. The proportional integral (PI) controller at the outer voltage control loop of VFDPC is tuned properly and the entire PWM ac-dc converter system is simulated using MATLAB/Simulink to ensure the dc output voltage follow the desired output voltage under steady state and dynamic conditions. Ac-dc converter utilizing the proposed VFDPC is able to generate three-phase input current waveforms that are almost sinusoidal with low harmonics contents which is less than 5% and near unity power factor (pf) operation
Multi-color Joint Probability Statistics Model-based Object Tracking System
No full textFor continuous target following under complex scene, an objective following calculation in light of multi-shading joint likelihood investigation model was introduced. The calculation embraced shading histogram to speak to the actual factual trademark with Camshaft standard and completed exploratory research in such angles as multichannel joint shading highlights measurements, projection delineate weighted preparing, the following window size and position ascertaining, calculation handling component of course. It utilised red, green, blue, tint, luminance channel shading as the objective watched attributes, and planned the computation technique given the likelihood measurement to recognise any shading focus from the compound scene. It likewise settled the counting method for following window size and position which adjusted the multi-shading model. Utilizing weighting projection outline strategy, the foundation obstruction around the objective potential territory was dispensed with. Finally, more reasonable joining judgment and the calculation cycle tenets were advanced. After the test accreditation, the ongoing execution and recognition proportion introduce a decent outcome
An FPGA-based Network Firewall with Expandable Rule Description
No full textWith the rapid growth of communications via the Internet, the need for an effective firewall system which has not badly affect the overall network performances has been increased. In this paper, a Field Programmable Gate Array (FPGA) -based firewall system with high performance has been implemented using Network FPGA (NetFPGA) with Xilinx Kintex-7 XC7K325T FPGA. Based on NetFPGA reference router project, a NetFPGA-based firewall system was implemented. The hardware module performs rule matching operation using content addressable memory (CAM) for higher speed data processing. To evaluate system performance, throughput, latency, and memory utilization were measured for different cases using different tools, also the number of rules that an incoming packet is subjected to was varied to get more readings using both software and hardware features. The results showed that the designed firewall system provides better performance than traditional firewalls. System throughput was doubled times of the one with Linux-Iptables firewalls