Volume 5, Issue 11, November 2014 Edition

IJSER Research Group http://www.ijser.org/forum/index.php Register for IJSER Research Forum      IJSER Xplore IJSER Xplore Research Paper Database

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



Computational Model, Energy Spectra and Assessment of 7MeV, 9MeV and 11MeV Electron Beans Emerged from Neptune 12PC Linear Accelerator Using Monte-Carlo Simulation Method: A Theoretical Study[ ]


The electron beams are widely used in radiotherapy. As the nominal energy of electrons is not sufficient to create suitable electron beams for remediation purposes, it is necessary to determine and use the dose data in depth for electron beams. The goal of the current research is to obtain the dose data in depth for 7MeV, 9MeV and 11 MeV electron beams emerged from Neptune 12PC linear accelerator and to assess the characteristics of the beams using Monte-Carlo simulation method. In this research, BEAMnrc code was used to simulate the considered accelerator. In addition, DOSXYZnrc code was applied to model the water phantom (RFA300). The profile of dose in depth along the central axis (percent depth dose) and its perpendicular axis (beam profile) was depicted for these electron beams in a 10x10 cm2 field using Monte-Carlo method. The R100, Rq, R85, R50 and Rp depth dose parameters were obtained from normalized profiles of dose in depth. The calculated profiles of dose in depth along the central axis and its perpendicular axis are of very good agreement with experimental profiles. Since different accelerators with similar manufacturer and model frequently have similar structures, it seems that the computational model of other accelerators from the same manufacturer can be accessible by simulating one of them and by changing the energy spectra and beam quality indices of simulated beams. Moreover, using the computational model of any accelerator, it can be possible that the effect of every remediation structure of accelerator on the electron beams is evaluated and finally, the resulted dose distribution is obtained and evaluated.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
ISOZYMES AND BIO-CONTROL ANALYSIS OF FUSRIAUM SPP. FROM POST-HARVEST DISEASED MANGO OF PAKISTAN[ ]


Electrophoretic studies of Isozymes and whole cell protein using Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) carried out to evaluate genetic diversity and intra specific variations among Fusarium solani and Fusarium oxysporum causative fungal pathogens of mango rotting in Pakistan. In present study 47 isolates studied for morphological variability and in vitro bio-efficiency of plants against Fusarium spp. Among them 37 isolates randomly selected for molecular analysis. Results revealed morphological characteristics of isolates were similar to each other. By using four isozymes Lactate dehydrogenase (LDH), Malate dehydrogenase (MDH), Glucose-6-phosphate dehydrogenase (G6PD), ß-glucosidase (ß-gluc) 24 phenotypes obtained. Among studied isolates MDH exhibit lowest activity. Isozymes banding pattern obtained by SDS-PAGE used to compute Jaccards similarity coefficients ranged 0.25 to 1.0 indicating genetic diversity in isolates. Cluster analysis with UPGMA showed isolates belonged to two main groups. Genetic distance observed D=0.15 to D=1.0. Among 37 isolates 90% belongs to Fusarium solani. Three plant species Azadirachta indica, Moras alba, Citrus lemon.L used as Anti-Fungal Botanicals (AFB) to control the growth of Fusarium spp. Comparative analysis of all three AFBs showed Moras alba most effective against F.solani and F.oxysporum. ANOVA showed that all genotypes and treatment was significantly different from each other at 5% probability level. In conclusion, cluster analysis of protein by SDS-PAGE, and electrophoretic detection of isozymes banding patterns were useful tools for differentiating Genetic diversity among Fusarium spp. and AFBs preferred to commonly used fungicides because of their environment friendly nature. This understanding can aid in devising ways of managing this potentially pathogenic fungus.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Determinism Modeling of PVM’s Non Deterministic Actions[ ]


Parallel computing operates on the principle that large problems can often be divided into smaller ones, which are then solved concurrently to save time by taking advantage of non-local resources and overcoming memory constraints. Parallel computing environment is realized using cluster based parallel computing architecture based system. MPI and PVM are the major tools used for establishing parallel computing environment. The performance of parallel application mainly depends on the methodology used for assignment of tasks. MPI follows the deterministic nature for assigning the tasks whereas the PVM follows the non deterministic nature which makes the PVM performance slower than that of MPI. In our work, we analyze the deterministic nature of MPI and non deterministic nature of PVM. This is realized by implementing matrix multiplication using both MPI and PVM. The computation is performed for different sizes of matrices over the different number of nodes. The results are compared with the computation time obtained for executions with MPI and PVM. Our work also focuses on the analysis of performance variations when the non deterministic nature for assignment of tasks of PVM is made deterministic forcibly.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
A Review on IPsec and SSL VPN[ ]


In today’s secenario of security, deciding Virtual Private Network (VPN) is a complex task. VPN connects remote sites or users using a public infrastructure (usually the Internet), thereby providing anytime and anywhere remote access to travellers. The objective of VPN is to add a level of security to the exchange of data from the organisations to remote sites. VPN creates a private tunnel for transferring the data securely. Internet Protocol Security (IPSec) and Secure Socket Layer (SSL) are the two dominant VPN technologies being used today. Both have their strengths and weaknesses. A comprehensive study of both the technologies has been presented in this paper. It exclusively explains the architecture and protocols of both the technologies including their advantages and disadvantages for real kind of applications.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
A Prototype Expert System for Academic Orientation and Student Major Selection[ ]


The present paper has for purpose to introduce a computerized approach for academic advising process in Moroccan universities in particular we discuss the case of university AbdelMalek Essaadi. This study proposes a prototype of an advisory expert system dedicated to new and incoming students to assist them select the most suitable majors they can apply to and the most convenient institutions they can attend. The expert system proposed uses an Object-Oriented approach to represent the data in the knowledge-base and a profiling phase to simplify the rule-base.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Analysis of Furniture Design Strategy Based on Ecological Aesthetics Conception[ ]


Ecological aesthetics is a subject that developed by low carbon movement because of the world-wide crisis. This paper incorporated the ideas of ecological aesthetics into furniture design and explained the furniture design strategy based on ecological aesthetics from the aspects of furniture’s material selection, modeling, function and structure in detail. The exploration of this will enrich furniture design strategy and provide scientific guidance for future furniture design. It will also determine the ecological aesthetic orientation of future furniture design, which can expect the harmonious intergrowth of human and nature.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
A Study on the Selection and Design of Ventilation Fans Powered by Photovoltaic System[ ]


This paper presents ventilation fan driven by induction motor powered by photovoltaic system. The proposed system is devoted for using the PV as an energy source for electrical motors. The investigations, shows that the performance of the fan is stable when it operates at its designed operating point. However, the deviation from such point, especially with high velocities, leads to instable operation and noise production. Consequently, the fan performance is affected and this leads to inefficient operation. The proposed system consists of PV system as an energy source, battery storage system for feeding electrical motors in addition to cooling fan load.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Analytical, numerical solutions and study of stability, resonance for nonlinear vibro-impact system under different excitation[ ]


Because of the existence of impacts, the vibro-impact system is discontinuous and strongly nonlinear, such as hammer-like devices, rotor-casing dynamical systems, heat exchangers, fuel elements of nuclear reactor, gears, piping systems, wheel–rail interaction of high speed railway coaches. Researches into the dynamic behavior of vibro-impact systems have important significance in optimization design of machinery and noise suppression. Hence, the complication of the dynamics of vibro-impact system has received great attention. In this paper, the analytical solution of non-linear vibro-impact system using multiple time scale method up to and including second order approximations is obtained. All resonance cases from mathematical solution are extracted. Also, the numerical solution of non-linear vibro-impact system using Runge-Kutta method of order four are obtained. The stability of the non-linear vibro-impact system at the worst resonance case is studied. The behaviors of the system at different values of parametric excitation are investigated. The effects of various parameters on the behavior of the system are studied. A comparison with the available published work is reported.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
FLEXURAL STRENGTH – A MEASURE TO CONTROL QUALITY OF RIGID CONCRETE PAVEMENTS[ ]


Flexural strength is a measure of the tensile strength of an unreinforced concrete beam or slab to resist failure in bending. It is useful in knowing the quality of concrete work done in road construction. Because of low initial cost, flexible roads are preferred, to concrete road pavement, but bituminous roads gets deteriorated during rainy season and maintenance becomes costly, therefore Government agencies have decided to go for concrete roads. Generally limestone as coarse aggregates for concrete roads are preferred but sometimes may not be easily available at all places nearby, therefore its replacement is necessary. Impact test, abrasion test & water absorption test were performed on demolished building waste concrete also, to recommend its suitability in making concrete roads as per Indian Standards Importantly boiling water curing has been done on some samples before flexural strength test for determining early strength of concrete, for predicting later age strength of concrete in roads. Behavior of flexural strength of concrete roads with lime stone, locally available is studied in this paper for concrete pavements. Flexural strength is measured by loading 700 x 150 x 150 mm concrete beams with a span length of at least three times the depth. The flexural strength is expressed as Modulus of Rupture (MR) in psi (MPa) and is determined by standard test methods ASTM C 78 (third-point loading). Flexural MR is about 10 to 20 percent of compressive strength depending on the type, size and volume of coarse aggregate used. However, the best correlation for specific materials is obtained by laboratory tests for given materials and mix design.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
WHAT DOES MEAN “CRIMINAL”?...[ ]


This scientific research focus that the Human Ancestors lived in WHITE PLANET (White Mars) in the early universe shall be considered as “CRIMINALS”. Criminals shall mean ideal persons who obey “Perfect law and order” having 100% integrity or absolute integrity as they lived under pure environment under the influence of Virgin radiation called as “J-RADIATION” (Zero hour radiation).

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
ITDS: Iris Tumor Detection System using Image Processing Techniques[ ]


Iris tumors, so called intraocular tumors are kind of tumors that start in the iris; the colored part of the eye that surrounds the pupil. There is a need for an accurate and cost-effective iris tumor detection system since the available techniques used currently are still not efficient. The combination of the image processing different techniques has a great efficiency for the diagnosis and detection of the iris tumor. Image processing techniques improve the diagnosis of the tumor by enhancing the quality of the images, so the physicians diagnose properly. Moreover, using some techniques such as edge detection and image fusion helps in detecting and segmenting the tumor, located in the iris. This paper aims to develop a detection system that automatically detects the presence of abnormalities or tumors in the iris. The suggested system combines different image processing techniques such as image filtering, images adding, canny edge detection, and image fusion. These methods are used in order to analyze and segment the tumor into the iris, and then mark this abnormal region onto the original grayscale image. The iris images are obtained from a public database available on the internet, “Miles Research”. The computer experimental results proved that the proposed detection system can successfully segment an iris tumor, and mark it to be then superimposed on the original image using image fusion.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
EEG Mental Tasks Classification Using Neural Networks[ ]


BCI (Brain Computer Interface) is the method of communication between neural activity of the human brain and an external device. The activity of the brain can be interpreted in terms of an EEG (Electroencephalogram) signal. This paper aims at classifying mental tasks by processing the EEG signal recordings recorded using sensors place on the scalp according to the Ten-Twenty Electrode system, performing wavelet decomposition and classifying it using different recurrent neural networks. The neural networks were trained and tested for all the five tasks and for combination of two task pairs. The accuracy of classification during comparison for all five tasks was found to be 82.33% and average accuracy for two task pairs was 99.5%.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Stabilizing the Barium Titanate by Different Kinds of Zirconia[ ]


The addition (30 mol.%) of different zirconia containing powders: cubic stabilized zirconia (8YSZ), tetragonal zirconia (TZ3Y), and TZ3Y+20 wt.% Al2O3 (3Y-20A) to barium titanate (BaTiO3) was studied. X-ray diffraction analysis of the sintered compact made of these powder mixtures confirmed the presence of single phase peroviskate-like structure. The microstructure of the sintered samples showed different grain sizes, for different kinds of zirconia additives. The relative permittivity and the dielectric loss of the sintered pellets were measured at zero and room temperatures. The highest relative permittivity was obtained for Samples having 30 mol.% TZ3Y. It was 5300 at zero temperature and 2250 at room temperature at 1kHz. The samples sintered at 1350oC showed lower values of the dielectric losses than those sintered at 1400oC.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
PERFORMANCE OF CARBON STEEL- POLYPROPYLENE FIBER REINFORCED SELF COMPACTING CONCRETE[ ]


The effect of carbon steel fibers and polypropylene fibers in self compacting concrete was studied in this paper. The self compacting concrete is a concrete that can be placed and compacted by its own weight. Self compacting concrete provides several economic and technical benefits and the use of fibers in self compacting concrete extents its possibility. Various researchers were performed the slump flow test, compressive strength test and flexural strength test to study the effect of fibers on fresh and harden properties of self compacting concrete. Polypropylene – carbon steel fiber reinforces self compacting concrete shows 29.36 % increase in compressive strength when compared to the control mix because it obtain benefits from both fibers. Maximum flexure strength with the use of both fibers in self compacting concrete can be achieved at 0.1 % use of polypropylene fibers and 1.0% carbon steel fibers as 71.58 %.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Performance Analysis of Frequency Hopping Techniques in DBPSK Modulation System[ ]


With more and more developments in wireless communication, spread spectrum modulation techniques have been widely used in various modulation systems. Frequency hopping technique is one of the types of spread spectrum system. In this paper, frequency hopping techniques are compared in a DBPSK modulation system which employs non coherent reception. Fast frequency hopping and multicarrier frequency hopping methods are compared based on the probability of error equations. It has been found that multicarrier frequency hopping techniques completely outperforms the fast frequency hopping techniques.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Experimental Evaluation of FDM Process for Model Material Volume Optimization for Cylindrical Primitives [ ]


Optimization of model volume can go a long way in enhancing the quantitative effectiveness of any layered manufacturing (LM) process. This work exhaustively evaluates the effect of contour width, raster width, raster angle, slice height, orientation and air gap on the model volume requirements for basic constructive solid geometry (CSG) primitives. Models have been derived and evaluated analytically and graphically using response surface methodology (RSM) technique to deduce the effect of aforementioned parameters on the model volume estimation for a Fortus 250mc modeler. This work establishes basic design principles for model volume estimation in a given build volume as well as evaluation of different spatial requirements for model volume optimization for Fortus 250 mc modeler in particular and FDM process in general.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
A Novel fuzzy vector control scheme for 3 phase induction motor[ ]


Classical vector control method is a widely accepted induction motor control algorithm, and is adopted in most of the modern induction motor drives. Classical vector control is quiet efficient and precise; but requires complex mathematical calculations. Also, various parameters of the controlled motor or system has to be predefined in the control algorithm part. Another problem associated with this control is its sensitivity to parameter variation. Parameters referred here are directly related to motor parameters like its resistance, self and mutual inductance etc. These are prone to variation with change of motor speed, operating frequency, temperature and even the environmental conditions.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Model Equation for Heat Transfer Coefficient of Air in a Batch Dryer[ ]


Heat transfer coefficients of dryers are useful tools for correlation formulation and performance evaluation of process design of dryers as well as derivation of analytical model for predicting drying rates. A model equation for predicting heat transfer coefficient of air in a batch dryer using BuckingHam Pi-theorem and dimensional analysis at various air velocities has been formulated. The model was validated by drying unripe plantain chips in a batch dryer at air velocities between 0.66 and 1.20m/s at corresponding temperatures between 42 and 66oC. Based on the analogy of heat and mass transfer rate equations for constant drying period, the prediction from the developed model agreed reasonably with the experimental data.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Optimal Load Dispatch in the South/ South Zone of Nigeria Power System by Means of a Particle Swarm[ ]


Solving the optimal load dispatch problem is key in the operation of power system, and several attempts have been made by using different techniques to solve these problems. Several traditional approaches, such as lambda-iteration and gradient method are applied to find out the optimal solution of non-linear problem. More recently, artificial intelligence (AI) computing techniques have received more attention and have been applied in a number of successful and practical applications. The purpose of this work is to apply the evolutionary computing technique known as Particle Swarm Optimization (PSO) to solve the optimal load dispatch problem- using some Power Stations in the Southern part of Nigeria as a case study. PSO is applied using the data of three (SAPELE) and six (AFAM) generating units. In this work, data has been taken from the Power Stations and some published work in which loss coefficients are also given with the max-min power limit and cost function. All the techniques are implemented in MATLAB environment. PSO is applied to find out the minimum cost for different power demand which is finally compared with lambda- iteration method.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Anticancer effect of Taxus baccata and Indian cow urine distillate (CUD) on mice treated with Diethyl Nitrosamine – Pathomorphological study[ ]


Cancer is a class of diseases in which a group of cells display the traits of uncontrolled growth, invasion and its spread through metastasis to the distant body places. Cancer is mainly caused by abnormalities in the genetic material of the transformed cell. The abnormalities may be due to the effect of carcinogen such as tobacco, smoke, radiation, and Chemicals like; DEN, aflatoxins and other nitroso compounds etc.Among various cancers, liver cancer is one of the most frequent that kill more than 600,000 people around the world every year. The present investigation was to study the effect of extracts of Taxus baccata alone and in combination with indigenous Cow Urine Distillate (CUD) in mice. Carcinogenicity was induced by diethyl nitrosamine (200µl/kg) (DEN). In a single dose DEN challenged animals were given extracts alone and in combination with CUD, daily and named them as test group. For control group no DEN and no treatment was given. Negative control was given only DEN, to check its carcinogenicity with control and test group. Tumors were developed in negative control animals, which died early but no mortality was observed in the test group. After six month the tissues from liver and kidneys were collected and histopathology was done to study the effect of carcinogen, plant extracts and their formulation with CUD. Microscopic examination of liver showed the presence of hyperplastic and anaplastic cells with the characteristic features of anaplasia including pleomorphism, hyperchromasia and presence of mitotic figure.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Performance Analysis of Doubly-Fed Induction Generator Connected to A Wind Turbine for Variable Wind Speed[ ]


This paper presents the model and simulation of wind turbine drives doubly-fed induction generator, which feeds AC power to the utility grid. Two voltage source converters are used to extract maximum power from variable wind speed. The converters are connected back to back between the rotor terminals of the induction generator and utility grid via common dc link. The grid-side converter controls the power flow between the DC bus and the AC side. The rotor side converter control the output power generated. Matlab/Simulink software package is used to simulate the system. The results of two wind speed and two blade pitch angles are obtained and compared.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Performance Analysis of Hybrid Electric Vehicle Battery Charger Using Voltage Oriented Control[ ]


In this paper, a high performance battery charger is designed to charge the batteries of hybrid electric vehicles. The charger of hybrid electric vehicle battery must be fully adapted to the battery to preserve the battery from damage and prevent harmonic current in the grid. Three-phase boost rectifier (universal bridge) using diode and isolated gate bipolar transistor is used. It has advantages of Bi-directional power transfer capability and unity power factor operation. The voltage Oriented Control method is used to control the DC output voltage. Matlab/Simulink software is used to simulate the mathematical model. The DC output voltage with unity power factor is obtained.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Performance Of Self Compacting Concrete Placed Underwater[ ]


The main objective of this study is to investigate the effect of anti washout admixture with various concentrations on fresh and hardened properties of self compacting concrete cast underwater. In this study, 16 mixtures was placed under water. The main parameters investigated in this study were: various concentrations of anti washout admixture, two dosages of superplasticizers, silica fume as replacement of cement content, limestone powder as replacement of cement content. The results obtained from this study indicates that the increasing AWA dosage from (0 to 1)%, for concrete mixes contain silica fume and limestone powder, reduced the slump flow by (25 - 33)% and (27-34)% respectively, decreases the standard washout mass loss by (69- 68)% and (75-78)% respectively, increased the compressive strength of concrete cast in standing water by (202 - 203)% and (266 -385)% respectively and increased the splitting tensile strength of concrete cast underwater by (169 - 191)% and (229 - 285)% respectively.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Experimental Simulation and Optimization of Performance of Four Stroke Spark Ignition Injector Engine[ ]


An engine test experiment was carried out using engine test bed. The test was performed within a speed range of 1500 – 4500 rpm. The performance of an engine whose basic design parameters are known can be predicted with the assistance of simulation program into the less time, cost and near value of actual. The essence of this work is to develop a computer simulation programs for the analysis of engine performance parameters of four stroke spark ignition engine before embarking on full scale construction. They will ensure that only optimal parameters are in the design and development of an engine and also allow checking and developing the design of the engine and its operation alternatives in an inexpensive way and less time, instead of using experimental method which requires costly research test beds. The optimal values obtained for engine test experiment are; sfc is 0.2902kg/kwh, efficiency is 28.80% and a/f is 16.50. For the designed window simulator, optimal values are; sfc is 0.2838kg/kwh, efficiency is 28.69% and a/f is 15.53. From the results obtained, it could be seen that the simulator results show good agreement with experimental results, the models are therefore said to be verified.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Organ Donor Identification System[ ]


Transplantation of human organs from one human being to another is one of the greatest medical breakthroughs of the country. In this paper, we are proposing a donor identification system to recognize the donors based on face recognition or through an Identification number. A centralized repository is maintained by the hospitals to store the required information of a donor which includes thumb impression, facial images and other basic details of the donor. In case of accidental death, the donor will be checked in our portal for verification about his organ donation and informed to the guardian. The process of taking the organ before the stipulated prescribed medical time will be initiated. In case of normal death, the person’s address and reference number will be checked and based on that, the organs will be taken with a formal confirmation from their guardian. This project focuses towards a full-fledged portal to register for organ donation, organ requisition and hospital details.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Literature Review of Ocean Current Turbine[ ]


This Paper discussed the historical review, current status of ocean current turbine, challenges and problems in the way of the ocean current turbine commercialization. As we known that fossil fuel resources in the world are limited and we can’t depend on them for the future energy needs of the world. For this purpose the researcher have find such sources of energy which are sustainable, green, environment friendly and have no impact on human lives, which includes renewable energy sources like solar, wind, and ocean energy sources. In this review paper, we also focused on the initiative of the ocean current energy technology and the efforts of different countries, companies and scientist for the development of ocean current turbine to extract power from ocean current energy including Marin Current Turbine Ltd (MCT), Florida Atlantic University (FAU). We summarized the current status and recent development in the field of ocean current turbine. We discussed some earlier projects and prototypes. The paper also discusses the impact of the ocean current turbine on the environment and marine life. Some of the current limitation and problems are also identified in the way of ocean current turbine development like grid connection.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
A Combined Power Quality Conditioner for a Dynamic Voltage Restorer Using a Novel Reference Signal Generation Method.[ ]


In this work a new method of reference signal generation method for the Combined Power Quality Conditioning is adopted in order to compensate both current and voltage quality issues of critical loads. The shunt converter discussed is used to eliminate distortions due to current harmonics from load side and a series converter eliminates voltage sag form the supply side. The algorithm developed algorithm for the above said controllers in order to generate a reference signal that is based on Instantaneous Reactive Power and nonlinear adaptive filter. The DC link control strategy is based upon PI controller. The proposed controller not only reduces the effects of voltage sag but also the current harmonics on the load side under distorted supply conditions. The proposed system was using simulation software MATLAB.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
UWB Square Microstrip Patch Antenna for C-Band Applications[ ]


A square UWB microstrip patch antenna with reduced ground plane is designed for C-Band applications. Proposed antenna has basic square shape with microstrip feed line of 50 ohm. Ground plane has to be etched at the back side of FR-4 substrate with permittivity of 4.7 and 1.6 mm in height. Proposed antenna showed satisfied impedance bandwidth which is 85.7 % for return loss response below -10 dB starting from 3.23 GHz to 8.1 GHz, with VSWR<2 along the impedance bandwidth. Reduced ground plane was good tuning parameter for return loss. In Satellite communications both downlink (3.7 to 4.2 GHz) and uplink (5.925 to 6.425 GHz) have been covered. Proposed antenna is easy to fabricate with its compact and simple design. Beside that it offers reasonable gain and Fairfield radiation pattern. Design and evaluation process were simulated using CST Microwave Studio 2010.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
PREDICTING THE STRUCTURAL RESPONSE OF A CORRODED PIPELINE USING FINITE ELEMENT (FE) ANALYSIS[ ]


This paper presents how the response of a cylindrical pipe with an external rectangular corrosion defect under internal pressure can be predicted accurately using the finite element method. Finite element analysis is an approximate solution method to any complex engineering problem. The method involves three stages which include the pre-processing stage where the material properties of the pipe are inputted into the Finite element software to facilitate modelling. The model is then meshed after which load and boundary conditions are inputted for the solution stage. The second stage is the solution stage where the software solves the model so created. The third stage is the post-processing stage that involves the visualisation and the analysis of the results obtained. A hand calculation of the stresses is finally done using approved codes to compare with the Finite element results obtained from which judgement is made. From the result of the FE analysis, it was revealed that, though the defect area bulged with more pronounced bulging at specific nodes at the defect area, there was no leakage or rupture given the limits of the analysis. The same result was observed based on the Von Misses stress and safe operating pressure failure criteria chosen to validate the FE analysis as both criteria showed that the pipeline is safe. It is therefore safe to conclude that the pipeline can be operated safely under the applied internal pressure however, a rupture analysis is recommended to reveal the effect of bulging, particularly where stress is highest at the defect area.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Comparison of the Mechanical Properties of Charcoal Unsaturated Polyester Matrix Composite and Snail shell Unsaturated Polyester Matrix Composite.[ ]


This study focuses on the comparison of the mechanical properties of charcoal unsaturated polyester matrix composite and snail shell unsaturated polyester matrix composite. The ground charcoal powder and snail shell powder were of the same particle size of 625microns. The ground charcoal was introduced into the unsaturated polyester at different concentrations. The same concentrations of ground snail shell were incorporated into the same percentage of unsaturated polyester. The mechanical properties of the two resulting composites were compared. The mechanical properties tested include, ultimate tensile strength, tensile strain at maximum load, bending strength at peak, deformation at peak, hardness and impact strength. Significant findings showed that the flexural strength snail shell unsaturated polyester matrix composite at 20wt% reinforcement was better than that of the charcoal at the same concentration. Also, snail shell unsaturated polyester composite showed better hardness and impact strength than its charcoal counterparts and those of unreinforced unsaturated polyester. Therefore, where flexural strength, hardness and impact strength are of paramount importance such as in some automobile parts, snail shell reinforced unsaturated polyester composite should be given priority.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------


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