Volume 5, Issue 10, October 2014 Edition

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Exhumation History and Tectonics across Purulia – Bankura Shear Zone: Constraints from Apatite Fission Track Analysis[ ]


The Purulia-Bankura Shear Zone (TPSZ) is a ductile- to-brittle-ductile, tectonically disturbed narrow zone of nearly 150 Km with a WNW-ESE trend. Two different rock assemblages, the Chhotanagpur Gneissic complex and rocks of the Shinbhum Group (SG) Occur on opposite sides of this shear zone The TPSZ borders the Meso- Proterozoic greenschist facies litho-package of the SG, which is comprised of meta sedimentary rocks, felsic volcanics, mafics/ultramafics, granitoids and an alkaline/carbonatite suite of rocks. The Chotanagpur Gneissic Complex contains amphibolites to granulite facies in the north mafic-ultramafic suites of rocks that are in close proximity to felsic volcanics, suggesting a bimodal character of magmatic episodes. The TPSZ was subjected to a compressional regime, and its development is attributed to thrusting and wrenching. The area initially underwent rifting, volcanism, granite plutonism, and shallow sedimentation followed by shearing. The possible reactivation and exhumation history of the area was analyzed using apatite fission tracks (AFT). Offset of AFT ages between the two rock assemblages occur on the two sides of this shear zone, indicating that reactivation occurred due to over-thrusting at approximately 500 Ma, which is further supported by the results of thermal history models. The youngest AFT age of 260 Ma means that this age is a result of the entire thermal history of the sample. Furthermore, samples from Sushina hills indicate AFT ages decreasing towards Beldih via Chirugora. We interpret this to be an effect of motion along this shear zone. The thermal history indicates that the samples were rapidly exhumed at 600 Ma, given that the samples were cooled rapidly and subsequently re-heated; therefore, a cooling-only history is impossible. Denudations are predominantly controlled by tectonic processes and to a lesser degree, by erosional processes. Most of the sample ages are in the 200-to 300 Ma range, but their track-lengths are quite short, providing thermal history information before 600 Ma .

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Development and Production of Brake Pads from Palm Kernel Shell Composites[ ]


Development and production of asbestos-free brake pad using palm kernel shell (PKS) was studied with a view to replace the use of asbestos whose dust is carcinogenic. The PKS were sieve into sieve grades of 100,350,710µm and 1mm. The sieve PKS was used in production of brake pad in ratio of 20% resin, 10% graphite, 15% steel, 35-55% PKS and 0-20% SiC using compression moulding. The properties examined are microstructure analysis, hardness, compressive strength, density, flame resistance, water and oil absorption. The microstructure reveals uniform distribution of resin in PKS. The results obtained showed that the finer the sieve size the better the properties. The results obtained in this work were compared with that of commercial brake pad (asbestos based and optimum formulation laboratory brake pad Palm Kernel Shell based (PKS), the results are in close agreement. Hence PKS can be used in production of asbestos-free brake pad.

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Strength and Eco-Friendly Characterization of Selected Lateritic Soils for Road Pavement[ ]


This paper is on the study conducted to reveal the strength and eco-friendly characterization of the lateritic soils from Ofada, Papalanto and Shagamu borrow pits in Ogun State of Nigeria when used as road subgrade, subbase or basecourse during the construction of pavements. Engineering properties of the laterite soils samples were determined through laboratory experimental analyses based upon relative density, wet sieve analysis, Atterberg limits tests, unconfined compression test, coefficient of permeability test, mass-volume relations, moisture-density relationship and California Bearing Ratio (CBR) test. Also, chemical composition, metallic composition and physico chemical properties of the laterite samples were assessed and characterized. The results have shown that the higher the material relative density value of the three samples the higher the value of their void ratio, degree of saturation, porosity, co-efficient of permeability and unconfined compressive strength. The materials contained coarse-grained sizes respectively as 54.46%, 66.975% and 29.63% and they can be classified as A-6(5), A-2-6(1) and A-6(12) which is an indication that the higher the coarse-grained the higher the strength. The CBR values in percentages for unsoaked soil samples respectively are 19.55, 31.5 and 13.106 while for soaked conditions are 13.45, 19.3 and 5.8 is an indication that they are suitable for subgrade. The pH values of 10.05, 13.10 and 11.56 respectively indicated that the materials are alkaline. Cadmium, lead and nickel were not detected in each soil sample and it meant that the materials are not hazardous.

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Onset Diabetes Diagnosis Using Artificial Neural Network[ ]


Diabetes Mellitus is a chronic, lifelong metabolism disorder that affects the ability of the body system to use the energy found in food. People living with high blood sugar will experience polyuria (frequent urination), which will make them to become increasingly thirsty (polydipsia) and hungry (polyphagia) .The improper management of this disease can lead to complication such as cardiovascular disease, kidney disease, eye disease, nerve disease, pregnancy complication. The database of Pima Indian diabetes has been considered for the diagnosis of the diabetes mellitus. This database comprise of certain attributes which are very adequate for diabetes mellitus diagnosis. The use of this attributes has enhanced the training and test classification of patients, whether diabetes is present or not. In this research work, multilayer feed-forward was created and trained with back-propagation algorithm which classify patient that are tested positive as binary 1 and patient that are tested negative as binary 0.The use of trained neural network gave recognition rate of 82% on test .This recognition rate was later compared to previous researches on diabetes where other types of algorithms was used such as ADAP algorithm, C4.5 algorithm, nearest neighbor with backward sequential selection of feature, EM algorithm. The success rate obtained from multilayer feed-forward trained with back-propagation algorithms is higher than these other algorithms.

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Modeling The Performance Characteristics of Optocoupler Under Irradiated Fields[ ]


Modern opto-electronic technology is seriously considered for communications, controlling and other applications. In many of these applications are used in a nuclear environment such as in the medical radiology, astronomy, nuclear physics and nuclear safeguarding. The interaction of ionizing radiation with devices materials leads to production of the defects in the material. The radiation-induced defects can modify the initial doping concentrations, creating generation recombination centers and introducing trapping of carriers. There is a scarcity of models which describe the optical, electrical and communication parameters of these devices working under the irradiation. Our mathematical model provides a clearer understanding and deeper analysis of the laboratory results and the ability to extrapolate and predict the most accurate results for changing of the performance characteristics of irradiated optocoupler devices. The radiation dose has several effects on the electro-optical optocouplers characteristics (output current, absorption coefficient, sensitivity and Current Transfer Ratio (CTR)). Also other factors such as materials, structure of the devices and type of incident radiation will have effects on the behavior of these devices under irradiated fields.

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International Scenario-How Corrupt are we Indians??[ ]


The problem in India is that Govt. reeks of corruption. No government file moves until official palm is greased. Inspite of the fact that corruption has been taken as a high priority for Indian Govt. still it is incurable. The Govt. of Prime Minister, Mr. Manmohan Singh framed a well developed legal and institutional framework, enacted RTI, formulated man anti-corruption/anti-bribery policies but all the efforts failed when it came to implementation and enforcement of these laws. A recent study unveils that in India Political parties which have prime responsibility to enforce anti- corruption laws have 86% of their structure corrupted which is followed by judicial system which is 75% corrupted. Consequentially corruption in India has reached all-time high with rates being exactly double of global prevalence. Globally, 27% people say they paid bribe when accessing public services and institutions in last 12 months while this percentage was 54% in India. While another EY global fraud survey report has given India 2nd position in corruption and bribery after giving Egypt the 1st position. Corruption Perception Index (CPI) of Transparency International has ranked India 94th out of 176 countries. India had scored only 36 on a scale from 0 (most corrupt) to 100(least corrupt).India has been ranked even below than its neighbor countries Sri Lanka and China. The problem is persisting due to excessive regulations, complicated taxes and licensing systems, numerous govt. departments each with opaque bureaucracy and discretionary powers, monopoly of govt. controlled institutions and lack of transparency in laws and processes. As globalization is increasing, there will be need of consensus laws and policies across the globe which will promote stricter ABAC policies in coming days

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Extensible Embedded Web Server for Online Farming[ ]


The advanced development in embedded system and web server can be integrated to erect a farm in fully automatic and technical method. The new ideas and technologies are used in the farm sector of the country to effectively utilize the available land resources. All farm parameters are measures using new technologies, using the threshold values decision is taken and the requirements are notified to the user using the web server. Sensor array is used to monitor the farm parameters and microcontroller is used for controlling purposes. The aim of this paper is to improve the productivity of the crop with low investment and also helps the farmer to produce the proper crop. The farmer can optimize the water usage, using the soil analysis, fertilizer usage amount is also reduced significantly. Wireless IP camera is used to feed live video of the farm. Using the Web server the farmer can view the farm status from anywhere in the world. this system has potential to attract the entrepreneurs to invest the farm sector also cultivate in geographically isolated areas.

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Applying Partial-Ground Technique to Enhance Bandwidth of a UWB Circular Microstrip Patch Antenna[ ]


The design of a Circular Patch Microstrip antenna, etched on an FR4 PCB, operating over a wide bandwidth for various applications in the range 1 GHz - 8GHz, with a partial ground plane has been presented in this paper. The design was optimized to obtain the most suitable configuration in terms of desired values of VSWR, S11 and Gain. The simulation was performed using the software Ansoft HFSS 13.0.0, a software that uses the Finite Element Method of problem-solving, which produced experimental results of the reflection coefficient and radiation pattern of the designed antenna. Upon fabrication, it was found that the results of the fabricated antenna and simulated antenna were in good agreement.

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University Examination Timetabling Using Tabu Search[ ]


University Examination Timetabling deals with scheduling examinations for students while satisfying specified constraints. Such constraints include avoiding overlap of courses offered by same students, ensuring fair spread of courses offered by a class and allocating suitable venues. This paper discusses an automated examination timetabling system for universities based on Tabu Search, a meta-heuristic technique. Tabu search starts with random generation of an initial solution which is typically sub-optimal. It then gradually optimises this solution by exploring the search space but avoids unnecessary exploration by keeping a list of recently visited areas in a Tabu list. Three versions of the timetabling system (labelled Sys_A, Sys_B & Sys_C), having varying penalties for violating constraints specified as hard or soft, were evaluated. Sys_A used equal penalty on all constraints, Sys_B used equal penalty on all hard constraints and a lower equal penalty on all soft constraints while Sys_C used different penalties for hard constraints depending on their perceived importance and the lowest penalty on soft constraints. The experimental dataset consisted of 153 courses with varying class sizes for a total of 5550 students to be scheduled within 25 days using 15 venues of different capacities. The data was obtained from the Faculty of Engineering and Technology, LAUTECH, Nigeria. The time taken to generate a timetable within 1000 maximum iterations and weighted relative error of generated timetables were used as evaluation metrics. The least error (best result) was obtained with Sys_B, having equal penalty on all hard constraints and a lower equal penalty on all soft constraints though with a second best (lower) simulation time.

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INCREASE OF TRANSIENT STABILITY OF THERMAL POWER PLANT WITH POWER SYSTEM STABILIZER[ ]


This paper describes the effect of Power System Stabilizers (PSS) on transient stability of thermal power plant power system after occurrence of disturbance in power system. Studies have been carried out for a thermal power plant having 2 nos. identical generating units. A dynamic model of the Kawai Super Critical Thermal Power Plant situated in the Southern Rajasthan is adopted to simulate the effect of PSS for damping of power system oscillations. Simulation studies indicate that AVR having supplementary control signal from PSS, transient stability of power system increase. Power oscillations damp out faster. Frequency of generators rapidly reach in steady state condition.

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The antimicrobial activity of pomegranate (Punica granatum) juice[ ]


In The present study microbial property of pomegranate juice was evaluated against both Gram positive and Gram negative bacteria (Staphylococcus aurous, Escherichia coli and Pseudomonas aeruginosa) using disk inhibition zone (Heart brain diffusion) method. The bacteria were obtained from reaserch center of Sulaimani Polytechnic University . The result of this study showed good antibacterial effect of pomegranate juice against both Gram negative and Gram positive bacteria, diameter of inhibition zones were significantly higher in pomegranate juice as compared to standard antibiotic disc. The present study concluded that the juice of Punica granatum have a strong antibacterial activity.

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Network Security Enabled Text Encryption Using Matrices[ ]


Most companies offering facilities to access host computers by their employees even from outside the organization. Network security involves all those activities which protect the information on the host computers/servers. Security of information has become a popular subject during the last decades. Since matrices have unique powerful concept, and can be easily understood, it could be applied as an efficient way of encrypting and storing text. This paper introduces a way of using positions of text represented in matrices for cryptography. The encryption system uses a matrix to store the text entered by the sender in the form of their positions, using an algorithm to encrypt these values.

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A New Hybrid Data Encryption and Decryption Technique to Enhance Data Security in Communication Networks: Algorithm Development[ ]


Data security is an important aspect of communication system that has always been a focus for exchanging information among parties at location physically apart. In today’s competitive market, different techniques have been developed to send data securely. We present a hybrid technique which combines the speed of Data Encryption Standard (DES) for encryption of data and Rivest Shamir Adleman (RSA) algorithms to encrypt DES secret key for proper key distribution and management. The proposed technique was implemented in Microsoft visual C# and the performance of the hybrid technique was assessed based on encryption and decryption time and throughput for different input text and image data sample of varying sizes. The results obtained shows that the developed hybrid technique has better performance in terms of speed of encryption (encryption time), throughput and the central processing unit (CPU) power consumption, when compared to other hybrid technique in literature. Hence, the developed hybrid technique is recommended for enhancing data security in modern applications, and systems where a high speed of encryption is required, without compromising the CPU power consumption.

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Business Analytics and its Use in Medical Area[ ]


Business Analytics is referred to as the utilization of the skills and technologies which integrate to generate high level performance in business operation of a particular field and helps in generating efficient results from the business operations. Business Analytics involves the usage of the applications which are deployed in the business operations. These applications have the ability to cater the analytical reports from the data of the business operations and the reports can then be used for the decision making of the enterprise.

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Geo-statistics Modeling of Shallow Soil and Rock Stratum Layers based on Geotechnical Data Field using GIS Tool : A case study of Al Kharj Region - Saudi Arabia[ ]


During the last decade, the continued demand to build heavy buildings in Al Kharj city requires more attention by doing a geotechnical investigation in order to design an optimized foundations based on geo-database and mapping that have been indexed in neighboring buildings for future projects. However, to design the foundations of heavy buildings we need to explore the shallow soil and rock stratum layers using boreholes up to 20 meters in order to know the thickness of each layer and its geotechnical proprieties before designing any foundations type. For this reason, the owner of each building must be chosen an appropriate foundations according to the civil engineering specifications. According to the field investigation and the geotechnical data from the boreholes which were included in various corners of the site, we observe that there are a difference in the geotechnical proprieties from one borehole to another concerning the thickness of layer and also the mineralogical composition of these layers as well as its geotechnical characteristics, that why we intend to apply a new tool such as GIS application in order to predict the 3D distribution of the soil and rock stratum layers thickness based on the geo-statistics modeling implemented within the GIS software. As an important results involved within this paper, we note the randomly distribution of the soil and rock stratum layers thickness which have no conformity of geotechnical proprieties with the best choice of heavy buildings foundations which were adopted by the designer, however, it is necessary to look for a new methods allow to develop and support geotechnical investigations, including the indirect applied geophysics methods. In addition, referring to the randomly geotechnical proprieties distribution of the soil and rock stratum layers thickness, it is necessary to build a geo-database using GIS software taking into account many sources of geospatial data (Satellite images, GPS, field surveying, and so on…) which help public and private companies that are active in the construction field to help to take decision for better designing the heavy buildings foundations and to avoid many reasons of foundations failure after construction phases. Finally, we recommend to complete these findings involved in this paper by taking into account the groundwater phenomenon at shallow depth where the reinforcement foundations can be affected by salts or any other chemical elements associated with groundwater surface. As well as the need to be in the short term to review and develop the required geotechnical investigations which can be integrated with the spatial database in order to help to take better decisions when we design the heavy buildings foundations in Al Kharj city and where else in Kingdom of Saudi Arabia.

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Protective Effect of Allium Ampeloprasum Against Toxicity Induced by CCL4 in Male White Rats[ ]


The protective effect of Leek (Allium ampeloprasum) extract against testicular toxicity induced by carbon tetrachloride CCL4 was studied. The experiment was conducted on 36 male rats distributed randomly into 6 groups of 6 animals: group (1) was kept as a normal control which received distilled water; rats of groups (2) and (3) were given only Leek extract only in a dose 200 and 400 mg/kg; and groups (4,5,6) received CCL4 at a concentration of 1 ml/L by oral administration for induction of toxicity on rats. Groups 5 and 6 received Leek extract 200 and 400 mg/kg with CCL4 respectively. Results showed that oral administration of Leek extract in rats with testicular toxicity by CCL4 increased the weight of testes and accessory genital glands, sperm motility, count and viability, serum testosterone, luteinizing hormone and follicle stimulating hormone. It could be concluded that treatment with Leek extract produced a protective effect against toxicity induced by CCL4 in the male rats.

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Catalytic Activity of Benzyl alcohol Using Modified Chitosan Schiff base Cu(II) Metal Complex[ ]


This study reports the synthesis of chitosan anchored Schiff base, ([2-oxo-1H-indol-3-ylidene] amino) chitosan and its Cu (II) metal complex. The complex was characterized by elemental analysis, FT-IR Spectrum, thermogravimetry analysis .The crystallinity of the compound was analyzed by powder X-ray diffraction technique .The catalytic efficiency of complex was studied in the oxidation of alcohols namely propanol, n-butanol, n-hexanol and benzyl alcohol using non toxic ecofriendly and easily available molecular oxygen as an oxidant. Furthermore the effects of various parameters including temperature, catalyst amount and effect of solvent have also been studied. The complex was found a suitable source in bringing out the oxidation reactions.

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Trends and Patterns of India’s High Technology Export with Special Reference to Pharmaceutical Products[ ]


Diversification of a country’s exports plays an important role in the economic growth of the developing countries. These countries are trying to increase its exports by exporting high technology products and improve their ranking in the world trade. India is no exception to this. The present study is an attempt to examine the competitiveness of pharmaceutical exports in India’s high technology exports, which is the largest sector amongst high technology commodities, with the US and Russian Federation by calculating different indices like Revealed Comparative Advantage (RCA), Revealed Symmetric Comparative Advantage (RSCA) and Intra Industry Trade (IIT) during 1991-2012. An extensive research effort has been made to comprehend the composition and direction of India’s Pharmaceutical exports with its top two export partners i.e. US and Russia using these indices. The empirical result of the study revealed that India has revealed comparative advantage in maximum pharmaceutical products with these two countries. Further, the result of the study also explained that TRIPS has a positive impact on India’s pharmaceutical exports. The study also revealed that domestic companies are more R and D oriented than foreign companies. The positive correlation of R and D expenditure and exports has been found in Indian Pharmaceutical companies. For India to become a top player in the global pharmaceutical business, the government of India needs to support foreign investments in pharmaceuticals sector in order to overcome the stiff competition in the global pharmaceutical market.

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Online Web Server Management System Using Li-Fi Technology[ ]


This paper focuses on using Li-fi technology in an online web server management system using Visible Light Communication system which is based on using of LED lights, their ability to behave at multiple degrees of freedom helps them operate in different ways by using multiple hopping technology. We are proposing an idea to use Li-Fi technology for the purpose of sending in more data at greater bandwidth using a server, processor and GPS/GSM device. The idea is that we use Li-Fi which enables in sending data at a greater speed from a user module to the destination work module, we use two modules where the lifi is connected to computer systems connected to a server and a GPS/GSM network. The focus of our work is to know how by using lifi, information can be sent and received by multi-hop wireless networks and that easy communication occurs between the user module and the work module.

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Structural Behavior of Timber Aluminum Composite Beams Under Impact Loads[ ]


An experimental along with numerical analysis has been carried out to investigate the behavior of simply supported timber aluminum composite beams under impact loads. The composite beams are made by connecting plywood slabs with aluminum beams (box sections) using adhesive epoxy material and mechanical fasteners (self tapping self drilling screws). The experimental program consists of testing a total of sixteen timber aluminum composite beams under impact loads applied by dropping constant weight from three different heights. The effects of several parameters are considered in the investigations. During the tests, the applied accelerations and midspan deflections are measured with time and impact forces are calculated for all the tested specimens. From the results of these tests, it has become clear how the impact characteristics of behavior of the tested timber aluminum composite beams are affected by the considered parameters in this study. A finite element dynamic analysis has been used for modeling and analyzing the tested composite beams. The adopted nonlinear finite element analysis through the use of ANSYS LS DYNA version 13.0 software gave compatible results with the experiment ones.

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A two stage DC-DC converter with isolation for renewable energy applicat[ ]


In this work, the design and development of a DC -DC Converter using a two stage buck–boost operation is discussed. This converter is suitable for low power application such as a matrix LED lighting system. The advantage of this converter is that instead of using two controlled switches as in case of a conventional converter, this circuit uses one MOSFET as a switch. The circuit uses two inductors and two capacitors as energy transferring elements that are able to provide a good quality, high efficiency power supply to the load. In this paper the design of TSBB converter is analyzed with closed loop control using a PI controller circuit . Even with smaller values of inductor and capacitor a highly efficient power supply can be made. The main feature of this circuit compared to the other circuits proposed is, comparing with the circuits designed previously with the same concept is that, in this work a galvanic isolation between the load and the source is provided. Thus by a suitable controller and galvanic isolation the ripple magnitude in the output is reduced considerably. A simulation model of the TSBB converter with results is presented

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Implementation of Multiple Kernel Support Vector Machine for Automatic Recognition and Classification of Counterfeit Notes[ ]


With the advance of digital imaging technologies, color scanners and laser printers make it increasingly easier to produce counterfeit bank-notes with high resolution.Almost every country in the world face the problem of counterfeit currency notes.Even receiving Fake notes from ATM counters,vending machines and during elections have also been reported at some places.There is a need to design a system that is helpful in recognition of counterfeit notes. In this paper, we propose a system based on multiple-kernel support vector machines for counterfeit banknote recognition. Each banknote is divided into partitions and the luminance histograms of the partitions are taken as the input of the system. Linearly weighted combination is adopted to combine multiple kernels into a combined matrix. Two strategies are adopted to reduce the amount of time and space required by the semi-definite programming (SDP) method. One strategy assumes the non-negativity of the kernel weights, and the other one is to set the sum of the weights to be unity.

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Optimization of Chemical Treatment Conditions of Ampelocissus Cavicaulis Fibre Using RSM[ ]


Ampelocissus Cavicaulis fibre was treated with NaoH, acetic anhydride, nitric acid, and zinc chloride. The influence of these chemicals, their concentrations, and pretreatment times on the resultant tensile strength of the fibre was studied. Response surface methodology was used to optimize the numeric and categoric factors involved. The results showed that the single and interaction effects of the chemical types and their concentrations were significant. Two factors interaction (2FI) model was proposed for predicting the ultimate tensile strength of the fibre. The optimum conditions obtained for the different chemical used are; 6% NaoH for 50minues, 14% Acetic anhydride for 70minutes, 6% Nitric acid for 50minutes, and 3% Zinc chloride for 70minutes. These optimum conditions were validated with little errors of less than 2.0%

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DC/DC Switching Power Converter with Digital Control based on FPGA[ ]


The paper first deals with the design of a DC/DC switching boost converter with digital control based on FPGAs, which is suitable for space applications. Digital control systems have significantly advantages over conventional pulse width modulator (PWM) controllers. Indeed, along with the general advantages of a digital system, such as reduced sensitivity to noise and component parameter variations, and the capability to realize sophisticated control algorithms, a digital controller can be hardened more easily against radiation induced errors than its analog counterpart. Besides, the implementation of the digital controller in a SRAM FPGAs provides more flexibility in terms of quick turn around time, and on orbit reconfiguration capability. However, SRAM based FPGAs are very sensitive to single event effects (SEEs). Therefore, we propose a radiation hardness by design (RHBD) technique based on logic duplication approach at both logic and device levels and on non-disruptive resynchronization mechanism that ensures the continuous operation of the converter when facing the issue of single event functional interrupts (SEFIs) that may occur in SRAM based FPGAs. This technique is validated with both VHDL simulations and experimental results.

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DC-DC CONVERTERS VIA MATLAB/SIMULINK[ ]


The design of power electronic converter circuit with the use of closed loop scheme needs modeling and then simulating the converter using the modeled equations. An attempt has been made in this paper to simulate all basic non-isolated power converters. This can easily be done with the help of state equations and MATLAB/SIMULINK as a tool for simulation of those state equations. So that these models can be readily used for any close loop design.

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Research of Novel Three-phase Inverter with SPWM Technique[ ]


This paper proposes a novel three-phase uncontrollable rectifier inverter without or with a quite small dc-link capacitor. Because a modulation wave reconstruction-SPWM (MWR-SPWM) technique is adopted which can greatly eliminate the harmonics of output voltage, the DC filter capacitor is greatly decreased or even removed. In addition, the size of the input ac filter and the output ac filter is reduced. The converter which is like a half bridge topology, has high power flow capability and minimum device stresses that can suitably interface a super capacitor with the drive train of a hybrid electric vehicle. The principle of operation and harmonics elimination of the novel inverter topology are elaborated.

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Detect of Polymeric Nanoparticles Size Using Laser Speckle Interferometry Technique[ ]


A new double aperture laser speckle interferometry technique is presented for detecting the size of polymeric nanoparticles, namely chitosan polymer. The optical setup uses a He-Ne laser for the source together with a lens to expand the laser beam and double apertures illuminating through both of them the same scattering surface. CCD camera provides images of the two superimposed speckle fields through the double apertures, interference fringes are formed within the speckle pattern, where the images of the two apertures overlap. Thus a periodic grid structure is introduced within each speckle .A first exposure was taken with the absence of the specimen and a second one after introducing the chitosan polymer sample in the way to the rough surface. By simple subtraction of the two digital pictures, we obtain a moiré nano fringe pattern that gives us information about the polymeric Nanoparticles size. The laser speckle interferometry technique is use to investigate the effect of moiré’ fringes on the particle size. TEM micrograph showed that the particle size of the samples is agreements with the results of Auto diluter submicron Particle sizer. The final dimension of the speckle grain size is controlled by the optical set-up. For samples with particle size smaller than the speckle grain size, the double aperture speckle interferometry should be used. The least measurable samples are the samples with particle size equal to the grid spacing formed within the speckles.

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