Volume 5, Issue 12, December 2014 Edition

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Direct Torque Control of Induction Motor Based on Genetic Algorithm[ ]


Direct Torque Control (DTC) became the most popular controller for induction motor control in the last two decades. The popularity is due to its simple structure, and high response for torque requirements compared with the other types of controllers. However, some unavoidable drawbacks exist such as torque and flux ripples, especially at low speeds, at starting, and when transition from state to another. Therefore, an accurate estimation for flux and torque is required. In this paper, a proposed of Genetic Algorithm (GA) is used for stator resistance optimization which can improve the DTC performance, and then other input /output data are generated for a sixth neural network training.The input/output data of the trained neural networks are generated from simulation of mathematical model of DTC equations. A neuro-estimator for stator resistance is proposed based on stator current and frequency, it can estimate the stator winding temperature, and then the stator resistance estimation becomes straightforward. A test program is used for training successful test for all the proposed neural networks. For simulation and test purposes, MATLAB/Simulink model is built based on DTC and implemented to show the effect of sampling time and stator resistance variation on DTC performance. The results obtained from the work simplify the use of neural networks and genetic algorithms with DTC for producing the estimated and optimized output signals of torque, stator flux and flux angle with fast and high degree of response and computations of such control drive. Simulation programs and models are performed by using MATLAB package based IBM-PC.

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Material Balance and Decline Curve Analysis Used as Procedure for Estimating Reserves (A case study of D4 and W1 Fields)[ ]


Reserves are frequently estimated before drilling or any subsurface development, during the development drilling of the field, after some performance data are available and after performance trends are established1.Several techniques have been developed for estimating and evaluating reserves2.This study therefore aimed at comparing material balance and decline curve analysis using two fields as a case study. These are D4 Sand Guico field4 as D4 field, and Wedged Shaped field taken as W13.The material balance method was carried out using the PVT(Pressure, Volume, and Temperature), and production histories of the reservoirs to estimate the reserve. Particular emphasis was laid on the determination of decline rate from the graph of production rate versus cumulative production which was also used to obtain the maximum produceable oil and consequently the stock tank oil initially in place (STOIIP) when the decline curve analysis was used.

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Characterization of natural geological materials; lignite, bentonite, shale and sand for Arsenic removal[ ]


Natural geological materials such as lignite, bentonite, shale and sand were collected from Java Island, Indonesia. The mineralogical, chemical and physical properties of these materials were characterized by XRD, XRF, N2 adsorption using BET method, zetasizer, TOC-L coupled with a Solid Sample Module. In addition, batch leaching experiments were performed to elucidate the stability of geogenic arsenic (As) present in the natural geological materials at different pHs. Finally, As adsorption potential of lignite, bentonite, shale and sand were evaluated by batch experiments. The results showed that acidic (pH < 6) and alkaline (pH >10) conditions destabilized the geogenic As content of the adsorbents. It means that the effectiveness of these natural materials as adsorbents is greatly limited by the pH of the contaminated system. Among these natural geological materials, lignite was the most effective adsorbent of As(V) followed by bentonite, shale and then sand whereas the amounts of As(III) adsorbed onto all adsorbents were lower than those of As(V). This indicates that As(III) is more mobile in comparison to As(V). The adsorption isotherms of As(III) and As(V) conformed to nonlinear types, either Langmuir or Freundlich.

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Lung Nodule Segmentation based on Modified Local Binary Pattern[ ]


In this paper a new CAD system is proposed for segmentation of lunch nodules in CT images which calculate volume of them.

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ENHANCING VIDEO RECOVERY OF WATER-MARKED VIDEO AFTER ENCRYPTION[ ]


The multimedia technology has a rapid development in various fields like medical, commercial, and defence. Therefore, security and privacy has become an important. In this paper the zigzag method based on block scrambling for the process of encryption and the compound mapping function is used for data hiding in encrypted video. The concept of applying the algorithm is explained in detail and its performance is also analysed. Its various parameters like performance in terms of speed and strength of encryption are compared with the original zigzag algorithm. The result enhances that the block based scrambling approach performs better and data recovery is lossless and highly privacy.

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Design of CPW-Fed Monopole Antenna with L- shape and T-shape for WLAN/Wi-MAX Applications[ ]


A novel dual-band design of a finite ground coplanar waveguide (CPW)-fed monopole antenna is presented for simultaneously satisfying wireless local area network (WLAN) and worldwide interoperability for Microwave Access (WiMAX) applications. The proposed antenna, comprising a rectangular planar patch element embedded with L shape and T-shape slots in the middle of the patch element. The simulated -10 dB bandwidth for return loss is from 2.0 to 2.2 GHz and 2.8GHz to 3.1 GHz, covering some of the WiMAX and WLAN bands. Prototypes of the obtained optimized antenna have been designed and constructed. The Antenna has 22.5 % (-10 dB return loss) band width ranging from 2 to 2.2 GHz, and -21 dB return loss is from 2.85 to 2.95 GHz. The parametric study is performed to understand the characteristics of the proposed antenna. Also, good antenna performances such as radiation patterns and antenna gains over the operating bands have been observed and VSWR is 1.6 at 2.4 GHz.

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A PV fed Switched Capacitor Inverter Using Series/Parallel Conversion with Minimum Number of Switches with an Inductive Load[ ]


This paper develops a photovoltaic (PV) array fed switched capacitor inverter is proposed. Here the output voltage is larger than the input voltage by switching the capacitors in parallel and in series. Here we don’t need any inductors which make the system large. By the usage of capacitors output voltage is boosted. Here photovoltaic (PV) is the main source of supply. By using the H-bridge technique and Marx-inverter structure the harmonics are also reduced by the multi-level output. Here induction motor is connected at output side & the motor will run under critical load also with minimum number of switches. The inverter can be used in hybrid electric vehicles (HEV) and electric vehicles (EV).

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Agro-tech in Malaysia and Literature Review Knowledge Sharing from Agro-Technology Using Nations[ ]


This paper demonstrates agriculture-technology in Malaysia and includes a literature review for some other countries. This study compares the Agro technology transformation program in several countries; Taiwan, South Korea, Thailand, Israel and Malaysia. How are they improving their economy, though agriculture? The concept of advanced technologies in agronomic systems has been given a significant role in the improvement of agricultural creations e.g. sustainable agriculture, livestock production and Crop yield, in order to maintain food security. This paper illustrates what kind of enhancement needs to heighten the Malaysia economy through agronomy, sharing a knowledge of agricultural technology and exploring the reasons why the agriculture economy is back on the policy agenda of Malaysia.

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Optimization of Principal Dimensions of Radial Flow Gas Turbine Rotor Using Ant Colony Algorithm[ ]


The gas turbine is the most versatile item of turbo machinery today. It can be used in several different modes in critical industries such as power generation, oil and gas, process plants, aviation, as well domestic and smaller related industries. The choice of the principal dimensions of a turbine rotor for a given set of inlet design specifications can be found by solving aerodynamic equations. An analytical method is indeed difficult and can be very time consuming, especially if the complete procedure has to be repeated for different cases. In this paper, we propose a novel feature selection algorithm ant colony optimization (ACO) for faster and better search capability. Proposed algorithm is easily implemented and because of use of a simple classifier in that, its computational complexity is very low. The performance of proposed algorithm is compared to the performance of Genetic algorithms.

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Impact assessment of FACTS and VSC-HVDC for damping power oscillations based on location and control strategy[ ]


This paper examines the impact of SVC, TCSC and VSC-HVDC on stability of electric power system. The stability study includes both static voltage stability and power oscillation for different kinds of control strategies based on linear and nonlinear theory. Dynamic responses have been investigated by injecting different disturbances into the test power system. For each device the efficiency of several Power Oscillation Damping (POD) strategies have been compared. Two criteria is selected to define the most appropriate coupled POD-devices: its specificity and efficiency. A brand view of the time response of each couple after two selected disturbances is provided at the end of the paper.

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Active Vibration Analysis of Piezo-Laminated Cantilever Beam[ ]


In active vibration control the vibration of a structure is reduced by using opposite directional force to the structure. Now a day’s active vibration control is frequently being used in aircraft, submarine, automobile, helicopter blade, naval vessel. In this paper a smart plate (aluminum plate) with one pair of piezoelectric lamination is used to study the active vibration control. The smart plate consists of rectangular aluminum beam modeled in cantilever configuration with surface bonded piezoelectric patches. The study uses ANSYS software to derive the finite element model of the smart plate. Based on this model, the optimal sensor locations are found and actual smart beam is produced. In this experiment we find a suitable control methodology by which we optimize the controller gain to get more effective vibration control with minimum control input.

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Optimization of Tribological properties of Al-6082/SiC Metal Matrix Composite by Grey-Taguchi’s Method[ ]


Tribological behavior of aluminium alloy Al-6082 reinforced with silicon carbide particles (0%,5% & 10% Volume percentage of SiC) fabricated by powder metallurgy was investigated . In this paper the optimization of dry sliding performances on the aluminum hybrid metal matrix composite was done using grey relational analysis in the Taguchi method. Different loads, sliding speeds, sliding distances and varying percentage of Silicon Carbide are selected as control factors. The multiple responses to evaluate the dry sliding performances are specific wear rate and coefficient of friction. A series of L27 orthogonal array of experiments for three different samples of Al-6082 SiC MMCs have been conducted on pin-on-disc wear tester apparatus, the volume loss and frictional force are measured. Based on grey relational analysis, the optimum level parameters for specific wear rate and coefficient of friction have been identified. Analysis of Variance (ANOVA) had given the impact of individual factors on the specific wear rate as well as the coefficient of friction. The results indicated that the four test parameters had a significant role in controlling the friction and wear behavior of composites out of which %vol. was identified as most influential parameter followed by load for specific wear rate and load for coefficient of friction.

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Hybrid Features Extraction based on Master Eye Block for Face Recognition[ ]


As technology is advancing, the demand of face recognition which is one of the biometric technologies is in-creasing day by day. During the last years, many researchers had introduced different techniques and different algorithms for accurate and reliable face patterns recognition. In this paper, a new face recognition system is presented. The system work flow passes through two main phases the enrollment phase and the recognition phase. The two phases share the two main modules of the system (preprocessing module and feature extraction module).The preprocessing include three stages; face clip detection, eye block detection and edge detection. After read face image as bmp file, the face detection stage pass through these steps; convert to HSV color space for skin color modeling, segmentation process is done for detect the skin ar-ea, noise removal, face localization. The eyes blocks detection stage include these steps; image smoothing, convert to gray scale, contrast enhancement and extract master eye cutouts block. The third stage consists of applying canny edge detection and thinning. All these steps to obtain the main edges of eye block. In this research the features vector that represent the face attributes consists of fifteenth feature obtained by applying moment invariant, color moment and geometric features. Probabil-istic neural networks (PNN) have been used to make a decision in matching stage. The system was tested over a dataset col-lected from 30 volunteers, where 10 images for each person were collected in different pose, expression and orientation. The achieved training rate was 100% and an excellent recognition rate 88.5% was achieved.

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Voice Based Guidance and Location Indication System for the Blind Using GSM, GPS and Optical Device Indicator[ ]


This paper presents a theoretical model and a system concept to provide a smart electronic aid for blind people. This system is intended to provide overall measures –object detection and realtime assistance via Global Positioning System(GPS). The system consist of ultrasonic sensor, GPS Module, GSM Module and vibratory circuit(speakers or head phones). This project aims at the development of an Electronic Travelling Aid (ETA) kit to help the blind people to find obstacle free path. This ETA is fixed to the stick of the blind people. When the object is detected near to the blinds stick it alerts them with the help of vibratory circuit (speakers or head phones). The location of the blind is found using Global System for Mobile communications (GSM) and Global Position System (GPS).

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Availability Analysis of the k-out-of-n:G system using Markov Model and Supplementary Variable Technique[ ]


Certain stochastic processes with discrete states in continuous time can be converted into Markov process by the well-known method of including supplementary variables technique. This paper presents Markov models for analyzing the availability for the k-out-of-n:G system with three types of failure (partial failure, complete failure under repair and complete failure under maintenance) using supplementary variable technique. The Markov method is used to develop generalized expressions for system state probabilities and system’s availability. An illustrative example is presented in order to illustrate the performance of the model. The transient and steady states have been presented when the failure and repair rates are variables and constants respectively. Lagrange’s method for partial differential equations is used to solve system governing equations when the failure and repair rates are variables. When both the failure and repair rates are constants, the system of differential equations with the initial conditions has been solved using Laplace transformation by the aid of Maple program. The steady state availability when both failure and repair rates are constants, has been computed.

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Structural, Dielectric and Ferroelectric Properties of Manganese (Mn) Doped Bismuth Titanate (Bi4Ti3O12) Ceramics[ ]


Manganese (Mn) doped Bismuth Titanate Bi4 MNX TI (3-X) O12 (X= 0.0, 0.1, 0.2, 0.3, 0.4) powders were prepared by high temperature solid state reaction route.

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Calculation of ionization energies, electron affinities, hardnesses and electro negativities, using many bases set of many methods[ ]


Representative atomic and molecular systems, including various inorganic and organic molecules with covalentand ionic bonds, have been studied by using density functional theory. The calculations were done with thecommonly used exchange-correlation functional B3LYP followed by a comprehensive analysis of the calculatedhighest-occupied and lowest-unoccupied Kohn-Sham orbital (HOMO and LUMO) energies. DFTcalculations of vibration spectra of many organic systems [1,2 ] , Density Functional Theory (DFT) calculations have been performed to supportour wave number assignments. The theoretica -lly predicted IR is well inagreement with that of experimental spectral data.

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Improvement of Dental Amalgam Properties By Increasing Copper Content[ ]


The aim of the present investigation is to study the effect of copper content on mechanical properties of dental amalgam. For this purpose five alloys have been casted composed of constant percentage of tin 30wt% and the copper content is vary as follow(5, 10, 15, 20, 25) and the rest was silver. The specimens were prepared and tested according to ADA specification No. 1. Mechanical properties (compression strength, diametral tensile strength, creep, dimensional change, and hardness) were investigated and it is found that all mechanical properties enhanced by increasing copper content. The compression strength is increased by 37.4% at one day and 35.2% at 7 days test. The diametral tensile strength is increased by 18.1% at one day and 13.5% at 7 days test. Creep resistance is increased by 71.1%. Vickers microhardness increases by 29.4% at one day test and 27.3% at 7 days test. Increasing copper content stabilizes the dimensional change of dental amalgam. All as compared to low copper content amalgam.

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Water Suitability in Basrah City Creeks for Different Use Figures[ ]


Basrah city, Southern of Iraq, is rich in water streams. It locates on west bank of Shatt Al-Arab River and being endowed with a network of creeks which are lateral branches of Shatt Al- Arab River. The main creeks in Basrah city are; Al-Sarraji, Al-Khorah, Al-Ashar, Al-Khandak, Al-Roubat, Al-Jubayla, and Shatt Al-Turk. However, with the rapid increase in population and the spreading of illegal residences along the creek banks, which is combined by the discharge of untreated sanitary sewage and industrial effluents, their water quality has deteriorated. Shatt Al-Arab River has received a lot of attention and many studies have been conducted to rout the spreading of different pollutants and assess their impact on its water quality and ecosystem. However, very few studies were performed on Basrah creeks and all of them focused upon the distribution of trace metals in their waters. The goal of this paper is to provide a picture of current water quality status in the main creeks of Basrah city and assess the suitability of their waters for drinking, recreation, and aquatic life uses. To satisfy this goal, a field work program has been conducted during high and low tide periods to gather water samples. The samples were analyzed for ten parameters including; DO, BOD, turbidity, TDS, pH, ammonia, total coliform bacteria, fecal coliform bacteria, nitrate, lead, and sulfate. The suitability of water has been assessed using CWQI. Based on results of this study, it was found that; the water in all of Basrah creeks has bad quality and the values of CWQI for drinking, recreation, and aquatic life uses of all Basrah creeks water are below 44 and vary over the range (13.0-32.1). This result gives poor rank for the three water use figures of all of Basrah creeks.

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CANYON GEOMETRY ANALYSES AND ITS INFLUENCE ON TEMPERATURE IN JIMETA YOLA ADAMAWA STATE[ ]


Urban geometry has complex influence on the micro climate of the urban environment. The most important geometric effect is that of the sky factor (SVF). This study has investigated the influence of Sky view factor on urban micro climate of the city centre of Jimeta. A total of 6 study site where selected within the Jimeta metropolis with Yola airport been the control station. Data on the LULC categorization, Sky view factor, temperature and attitude where collected from these sites and were analyzed using the appropriate methods. The finding reveals that the Ribadu square (sites 4) has the highest SWF with (0919). This means that over 90% of its sky is open and unobstructed by vegetation and building. The lowest record was obtained at Gwadabawa (site 2) with 0.75516 SVF. This means that over 75% of the sky in Gwadabawa is not obstructed by buildings, vegetation or standing objects. The difference between the two stations which is 0.1634 reveals that there is no wide variation in the sky view factor among or between the sites in the study area. The mean sky factor for the study area is 0.8752, which signifies that generally speaking about 87% of the sky in Jimeta metropolis is visible. This suggest therefore, that the SVF is not well pronounced in Jimeta (Northeast Nigeria) compared to other studies or research conducted in Kano (North-west Nigeria) and in Onitsha (South-east Nigeria).

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Exploration of Additional Mechanical Phenomena of Laser-Tissue Interaction Contributes to the Damage and Elimination of the Small Blood Vessels[ ]


This study was designed to carry out a comprehensive experimental analysis of the mechanical effects of the irradiated tissue models with nanosecond laser pulses at three different repetition frequencies are delivered using a fluence value close to the threshold fluence and, to find threshold fluence for bubble formation in a scattering tissue model.Two tissue models of agar phantoms incorporating light scattering. The first was made of a single layer, while the second, it was composed of two layers, thick layer and the scattering one, is constituted by a mixture of liquid agar gel and Intralipid. Nd:YAG laser 532 nm, pulse duration of 5 nanoseconds and a 90 femtosecond laser was used for irradiation .The result showed that permanent or transient bubbles made reckoning on the laser fluence , variety of pulses and repetition rate. Scattering added to the tissue model increased the threshold fluence for plasma formation. The permanent and transient bubble can be produced by single nanosecond laser pulses while femtosecond laser pulses were always produced transient and half the initial size than those produced with nanosecond laser pulses.

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Experimental Study of The Energy Separation in Counter Flow Vortex Tube[ ]


The present paper investigates an experimental work to study the performance of manufactured counter flow vortex tube incorporated with set of generator nozzles of N = 2, 3, 6 and aspect ratio, AR = 1.4. The effects of inlet air pressure, hot tubes length to diameter and number of nozzles on the splitting air temperature are studied. The study includes evaluation of the COP for the cooling and heating processes. It is found that an optimum value of COPref = 0.24 as well as for COPHP = 0.3 are obtained. The findings encourage using the vortex tube in the applications of cooling and heating processes.

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Analysis and Simulation of Networking Protocols in Constellation Flying System for Inter-Satellite Communication[ ]


The High rate of transmission of data makes IEEE 802.11 protocol ideal for WLAN (Wireless Local Area Network). The configuration of the flying satellite is such that the distance between the satellites is very short and much alike WLAN, hence to elevate the throughput IEEE 802.11 protocol can be used for the inter-satellite communication. Nevertheless the fact is that the inter-satellite distance is large as compared to the distance in WLAN. Thus IEEE 802.11 protocol needs to be altered and optimized to make it usable for configuration of inter-satellite communication. Two variants of MAC namely Distributed Coordination Function (DCF) and Point Coordination Function (PCF) are examined for the configuration of flying satellite system. Inter-frame reformulation, merging of smart antennas with the protocols proposed in MAC and the acceptance of the minimal contention window are suggested in this paper. In the end we examine the performance of the altered protocol after simulations.

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Moment of Inertia for a Baseball or Softball Bat[ ]


In selecting a baseball or a softball bat, both weight and weight distribution should be considered. However, these considerations must be individualized, because there is large variability in how different batters swing a bat and in how each batter swings different bats. Previous research has defined the ideal bat weight as that weight that maximizes the batted-ball speed based on measurements of individual swings, the concept of the coefficient of restitution, and the laws of conservation of momentum. In this paper, a method is given that extends this approach to recent bat designs where the moment of inertia can be specified. The data presented in this paper show that all of the players in our study would probably profit from using end-loaded bats.

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Strength and Permeability Characteristics of Selected Laterite Stabilized Using Powermax Cement[ ]


Laterite soil samples classified as A-2-6(1), A-6(5) and A-6(12) by grouping according to AASHTO that are considered not suitable for use as pavement base course were stabilized using a new brand of Portland cement called Powermax. In this research, Powermax cement was mixed with the lateritic soils respectively at varying proportion by weight of 6%, 8% and 10% whilst their respective Unconfined Compressive Strength (UCS), Coefficient of Permeability k, Optimum Moisture Content (OMC), Maximum Dry Density (MDD) and California Bearing Ratio (CBR) were evaluated in the laboratory. The results of the unconfined compressive tests show that the value of compressive stress of the stabilized lateritic soil materials increases as Powermax cement proportion increases from 6% through 8% to 10% for both uncured and cured specimens of A-2-6(1), A-6(5) and A-6(12) soil samples. Also, the value of k of the stabilized lateritic soil-cement mixture moved from good state of 6 10? mm/sec at 6% to poor state of 7 10? at 8% and 10%. At 10 % stabilized lateritic soil-cement mixture considered optimum, the OMC values are 15.8%, 15.5% and 15% whilst the respective MDD are 1912 kg/m³, 1864 kg/m³ and 1831 kg/m³ for the corresponding soil group of A-2-6(1), A-6(5) and A-6(12).

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Performance Analysis of Split TCSC for Fine Power Flow[ ]


With the increase in demand for electrical energy, the size and complexity of the power system has been increased. As a result of this, some transmission lines are heavily loaded and the system stability becomes a limiting factor for power transfer. Hence, power flow analysis is essential for a secure power system operation. A Thyristor controlled series capacitor (TCSC), the second generation of flexible AC transmission system (FACTS) devices, can control the line impedance through the series introduction of a thyristor controlled reactor across a fixed capacitor with the transmission line. The TCSC furnishes inductive as well as capacitive reactance compensation to alter the power flow of the transmission line. The difficulty in tuning the TCSC i.e., large change in reactance offered by TCSC at critical region makes inconvenience in increasing the transmission line loading capacity.

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Electrical Tracking Performance of Thermoplastic Elastomer Nanocomposites Material under High Voltage Application[ ]


Thermoplastic Elastomer (TPE) nanocomposites are polymeric materials which made up of thermoplastic and elastomer containing a small amount of nanometer-sized fillers. From the stand-point as outdoor electrical insulation under high voltage application, the most common cause of polymeric insulation failure is electrical tracking. In view of this, the paper deals with application of nanofillers added to TPE material in order to obtain high endurance to tracking degradation. The blend of ratio 4:1 of high density polyethylene (HDPE) and epoxidized natural rubber-50 (NR) added with and without MMT, Al2O3 and SiO2 nanofillers were presented. The electrical tracking test using the inclined-plane tracking method was conducted to analyse the leakage current performance and carbon track characteristics on the material surface. The leakage current data patterns were monitored using computer-based system and the carbon track propagation are visually observed. The results revealed that the leakage current of TPE without nanofillers is lowest among the samples thus inhibited electrical tracking growth. In addition, carbon track propagation of different material compositions is also visually observed.

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AN EFFICIENT TECHNIQUE FOR ICI REDUCTION USING WINDOW FUCTIONS[ ]


In Orthogonal Frequency Division Multiplexing (OFDM) multi carrier modulation technique is used for high data rate stream transmission. These carriers are orthogonal to each other. The guard bands are not used in Orthogonal Frequency Division Multiplexing (OFDM) system. With the help of OFDM technique the spectrum of users can overlap and enhance the spectrum efficiency of the system. In this paper we are used Kaiser, Hamming, Hann, Blackman and Gaussian window functions. With the help of these window functions we are comparing their ICI and power of desired receive signal. So that we enhance the quality of OFDM modulated transmission system.

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A Survey of Trust Based AODV Routing Protocols in MANETS[ ]


Mobile Adhoc Networks are type of wireless network which are infrastructure less, self organizing, highly mobile and quickly deployable. There is no central authority, the communication occur hop by hop based on cooperation among the nodes. Thus, secure routing protocols are needed which are robust and ensure that the nodes in the network behave in trustworthy manner otherwise detect and eliminate the untrustworthy nodes which degrade the overall network performance. There are several trust based AODV routing protocols given in the past. In this paper, we have given a survey of trust based AODV, in which concept of TRUST is used to ensure secure routing and improved network performance.

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Using Digital Filters and Fractal Filter To Segmentation the Medical Image[ ]


Fractal geometry used to describe the local grey level change in digital image . This research aims at using number of filters to get a butter image than the original one by blurred image edge detection and blurred image sharpening for using local fractal filter and Discrete Cosine Transform digital filter to segmentation the medical images that uses, this beside is important for purpose the diagnosis and the medicament in medical applications . The concept is evaluated by comparing of the performance fractal filter with operators such as, Gaussian and Laplace operator. Results show a similar performance in a low-noise environment and superiority of the fractal operators in a high noise environment, by designing program using MATLAB. The inclusion of the operators into an edge based segmentation scheme revealed the same results for an application in image segmentation.

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Pages   [1] [2] [3] [4] [5] [6] [7] ...[U]