IMPACT : International Journal of Research in Engineering & Technology

9-14

Authors: Aashish A. Gadgil

Image segmentation is one of the most important steps involved in performing higher level image processing, e.g. Medical Imaging (locate tumors, tissue volumes etc.), Face recognition, Video surveillance. A lot of researches have dedicated to this field because of its intrinsic dilemma, but there still remain a wide range of shortcomings in the current segmentation methods. If used in case of satellite imagery which contains tremendous data volume and very multifarious ground feature distributions, it will encounter even more difficulties in extracting meaningful and valuable patterns. In this paper, satellite imagery is classified into two types: the gray value and surface imagery, and then look for suitable segmentation methods. Various segmentation algorithms are implemented that are also illustrated and validated with typical applications on segmenting and extracting objects of interest from the images.

23-34

Authors: Dhaval M. Parikh & G. J. Joshi

Indian infrastructure investment in general and highway construction in particular have seen manifold increase in the recent times. This has brought about a paradigm shift in the way in which the highway construction industry has been conducting its business with increased pressure on its stakeholders, namely the employers, the contractors and the consultants for high quality and timely project delivery. Disputes and arbitration has also seen a dramatic rise in past decade or so. Majority of the projects due to several reasons encounter time overrun. This paper presents the study of multi-level break down structure of the claim-causes and its impact on the project time overrun with multiple claim-causes acting simultaneously. It presents the prediction model for predicting time overrun in highway construction contracts in India. It is proposed to use this model for diagnostic as well as predictive tool to understand and possibly mitigate time overrun.

39-46

Authors: V. Ch Sandeep Raj, B. N Malleswara Rao & V. V. S Prasad

The design of a bulk carrier ship hull is done either by using B.S.R.A results or Taylor s series by conventional methods which may results in some inaccuracies in the design. Two bulk carriers of 30,000 DWT and 53,000 DWT are designed using the computer aided design software and the results are shown the ship is designed using the modern computer design application softwares.

57-68

Authors: Ibtihal A. Mahmood, Walaa W. Jameel & Lubna Alaa Khaleel

The erosion wear resistance of Ni base super alloy (Monel 400) can be improved by thermal sprayed coatings produced by the high velocity oxygen fuel (HVOF). In this work, (Monel 400) is coated with two different types of coatings, the first one is Al2O3+5% TiO2 and the second is Al2O3 +15% (7-8YSZ), these layers were made of 350-400 μm as top coat, pre-sprayed with 50-100 μm of 4NiCr5Al as a bond coat To study the erosion wear behavior of the coatings, erosion test apparatus was designed according to ASTM G-76 also a plan of experiments based on the Taguchi technique is used to acquire the erosion test data in a controlled way. An orthogonal array and signal-to-noise ratio are employed to investigate the influence of the coating materials, impingement angle and stand-off-distance on the erosion rate. The study reveals that the coating materials is the most significant factor influencing the erosion wear rate. Al2O3 +15% (7-8YSZ) has higher wear resistance than Al2O3+5% TiO2, Porosity influences their performance when subjected to wear (loss of thickness increased as the porosity increased), The measurement of hardness before and after the wear tests indicates that there was no significant change in either the metal or the coated samples at 3000C for 1 hr. To assess adherence index, porosity and the hardness for the Al2O3 +5% TiO2 coating are 84%, 9% and 454 HV0.3 respectively while for the Al2O3 +15% (7-8YSZ) coating are 80.1, 17% and483 HV 0.3 respectively.

77-86

Authors: Ibtihal A. Mahmood, Walaa W. Jameel & Lubna Alaa Khaleel

The oxidation resistance of Ni base super alloy (Monel 400) can be improved by thermal sprayed coatings produced by the high velocity oxygen fuel (HVOF), In this work, (Monel 400) is coated with two different types of coatings, the first one is Al2O3+5% TiO2 and the second is Al2O3 +15% (7-8YSZ), these layers were made of 350-400 μm as top coat, pre-sprayed with 50-100 μm of 4NiCr5Al as a bond coat. The results revealed that the Al2O3+5% TiO2 have higher oxidation resistance than Al2O3 +15% (7-8YSZ) in the temperature range (600-800)0C in air for 15 h at 3h cycle. X-Ray diffraction (XRD) was used to identify phase formed in the surface layer of as-coated specimens before and after oxidation test. Phase transformation is accompanied by volume expansion, leading to compressive stress during oxidation. It is mentionable that the compressive stresses lead to increase of the hardness. Hardness of Al2O3 +15% (7-8YSZ) at (600-700 and800)0C is (723,765 and812) HV 0.3 respectively is more than Al2O3 +5% TiO2 at the same conditions (610,645 and 690) HV 0.3 respectively. Porosity transferred oxygen from top coat layer toward the bond coat (4NiCr5Al). Hence, a thermally grown oxide layer ( ) was formed on the metallic bond coat and internal oxidation of the bond coat occurred during oxidation. Microstructural characterization of coatings demonstrated that the growth of the TGO layer with Al2O3+15%YSZ is more rapid than TGO with Al2O3+5%TiO2. To assess Adherence Index, porosity and the hardness for the Al2O3 +5% TiO2 coating are 84%, 9% and 454 HV 0.3 respectively while for the Al2O3 +15% (7-8YSZ) coating are 80.1, 17% and483 HV 0.3 respectively.

7-12

Authors: V. I. Loganina, L. V. Makarova, R. V. Tarasov & K. A. Sergeeva

The information about the technology of synthesis of filler based on calcium Hydrosilicates. The article provides information about the properties of dry construction mixtures prepared with a fine composite binder based on calcium hydrosilicates. It is shown that the use of lime composite binder in the formula of dry construction mixtures improves the operational stability of lime topcoat.

11-16

Authors: Vijay Karma & Himanshu Borade

Fault detection and diagnosis of gear transmission systems have attracted considerable attention in recent years, due to the need to decrease the downtime on production machinery and to reduce the extent of the secondary damage caused by failures. This paper deals with fault diagnosis of a spur gearbox having spalling defect in driver gear using narrow band demodulation technique through MATLAB software. For this an experimental setup is fabricated. The vibration signals are captured from the experiments and the burst in the vibration signal is focused in the analysis and the frequency of the faulty gear is found out.

25-34

Authors: Shriram Gupta & Sarita Singh Bhadauria

This paper compares and improves the bit error rate performance with the minimum mean squared error (MMSE) equalizer applied to wireless multiple antenna systems (MIMO) by using Orthogonal Frequency Division Multiplexing (OFDM). In Spite of much prior work on this subject, This reveal several new and surprising analytical results in terms of signal-to-noise ratio (SNR) by changing the OFDM parameters.

41-50

Authors: Irfan Jamil, Rehan Jamil, Zhao Jinquan, Rizwan Jamil & Abdus Samee

XZ-Ⅱtype rotary inverted pendulum is a typical mechatronic system; it completes real-time motion control using DSP motion controller and motor torque. In this paper, we recognize XZ-Ⅱrotational inverted pendulum and learn system composition, working principle, using method, precautions and software platform. We master how to build mathematical model and state feedback control method (pole assignment algorithm) of the one order rotational inverted pendulum system and finish simulation study of system using Matlab. In the end we grasp debugging method of the actual system, and finish online control of the one order rotational inverted pendulum system as well.

57-64

Authors: S. C. Chaudhari, C. O. Yadav & A. B. Damor

The present paper describes an improve the head of mixed flow pump impeller, Computational Fluid Dynamics (CFD) analysis is one of the advanced CAE tools used in the pump industry. From the results of CFD analysis, the velocity and pressure in the outlet of the impeller is predicted. The optimum inlet and outlet vane angles are calculated for the existing impeller by using the empirical relations. The CAD models of the mixed flow impeller with optimum inlet and outlet angles are modelled using CAD modelling software Solid Works 2009. By changing the outlet angle and the No. of blade of impeller the head of the impeller is improved to 86.75m. From this analysis it is understood that the changes in the inlet blade angle and No. of blade change the head of the impeller. From the CFD analysis the head of the impeller with optimum blade angles is calculated as 76.46m. Thus, head of the mixed flow impeller is improved by 10.29m by changing the inlet and outlet blade angles and No. of blade.

77-84

Authors: Sonu Bittoliya & R. P. Narwaria

In this paper, the electrocardiogram (ECG) signal is vulnerable to noise and artifacts, it is essential to noise removing using neural network, the noise in order to support First 3600 of noisy heart signals are collected from MIT-BIH data base. In this paper the use of moving median filter & artificial neural network. The available filter for power line interference need a reference channel or regard the frequency is fixed 50/60Hz. In this literature of the last twenty five years several solution of noise removal on electrocardiogram (ECG) signal can be found. The spectrum of the ECG signal is extracted from the two databases arrhythmia and supraventricular. Baseline wander is removal using the moving median filter. The results shows that the intelligent artificial neural network system successfully denoised ECG signal. This study mainly focuses on cutoff frequency calculating best performance MSE.

93-102

Authors: Rashmi R. Keshvani

In a liquid a satisfactory method of defining the diffusivity so that it will be independent of relative composition, has yet to be devised. The recent development of effective methods for the calculation of mass –transfer rates from particle surfaces, now brings forward the need of considering pore diameters, permeabilities and porosities. Knowledge of liquid diffusion rates in porous solids has applications in solid-liquid extraction and in catalysis. Piret E. L., Ebel R.A. Kiang C.T. Armstrong W. P. aimed to investigate about liquid diffusion rates which would be of value in the study of actual systems involving porous carrier solids and to obtain idealized extraction systems. In their work, they presented theoretical expressions and experimental data for extraction from single capillaries, from beds of uniform glass beads and from inert porous spheres carrying single-phase solutions of soluble substances. They introduced the concept of pore shape factor. Pore shape factor is equal to the ratio of the actual to the theoretical extraction time or for an actual sphere of measured radius R, an equivalent, idealized sphere of radius KR, (K> 1.0) can be postulated, whose structure offers no resistance to diffusion. The square of this constant, K^2, will be called the pore shape factor. This factor is used in interpreting and correlating the extraction data. Here in this paper the author intends to interpret the results, obtained in their investigations and to derive a simple formula to determine this pore shape factor. For this purpose, Euler’s Summation Formula and Abel’s identity are applied to the analytic solutions obtained for their experiments. This approximation is obtained only for small values of Dt/R^2 , where D is diffusivity, t is time and R is measured radius of sphere. The formula is verified for experimental data. It shows nice agreement with the experimental data.

109-120

Authors: S. Subitha & S. Sujatha

Information Retrieval is an emerging research area in the field of Information Retrieval. Due to the immense amount of data in the WWW, it is very tough for the user to retrieve the relevant images. Traditional Image Retrieval approaches based on topic similarity alone is not sufficient nowadays the content based image retrieval (CBIR) are becoming a source of exact and fast retrieval. A variety of techniques have been developed to improve the performance of CBIR. Data clustering is an unsupervised method for extraction hidden pattern from huge data sets. With large data sets, there is possibility of high dimensionality. Having both accuracy and efficiency for high dimensional data sets with enormous number of samples is a challenging arena. In this paper the clustering techniques are discussed and analysed. Also, we propose a method HDK that uses more than one clustering technique to improve the performance of CBIR.This method makes use of hierachical and divide and conquer K- Means clustering technique with equivalency and compatible relation concepts to improve the performance of the K-Means for using in high dimensional datasets. It also introduced the feature like color, texture and shape for accurate and effective retrieval system. This survey gives an introduction to content-based image Retrieval and explores the different types of retrieval methods

11-20

Authors: A. P. C. Saratha Devi & V. Mahesh

Changes in lighting condition impact the appearance of face images to a large extent. Therefore it becomes very difficult to recognize a face under different lighting conditions. The face images have to be normalized to overcome the illumination variation to get recognized. The work presented here analyzes the performance of the illumination normalization methods of face images like DCT (Discrete Cosine Transform) normalization, Wavelet Denoising, Gradient Faces, Local Contrast Enhancement, and Weber’s law under different lighting conditions. The face images are preprocessed and normalized by each normalizing method to reduce the effect of illumination. To analyze the performance of each method, the features of these preprocessed images are extracted using Principal Component Analysis (PCA) and the recognition is done based on Euclidean Distance. In this paper, the advantages and drawbacks of each method are analyzed. The recognition rate and computational time of these methods are compared. The Extended Yale B database is used in this work.

25-34

Authors: Jayesh N. Modi

Easy configuration and quick deployment of Wireless Ad hoc Networks make such networks more suitable for various applications including multimedia applications (e.g. VOIP, video conferencing etc). The traffic patterns (video and audio streams etc) generated by multimedia applications are more complicated than those of simple voice and data traffic. The available bandwidth for Wireless Ad hoc Networks fails to meet the requirements of multimedia transmission, which results in packets loss, delay and decrease the quality of transmitted multimedia data. Network Coding is a technique which can be used to overcome such problems over Wireless Ad hoc Networks. In Network Coding technique, it allows a node to combine data (packets) received from different input links, encode received data and send encoded data on its output links (instead of just storing and forwarding). In this thesis work, a variant of Network Coding that is Random Linear Network Coding (RLNC) with Multi Generation Mixing (MGM) is employed for MPEG-4 video traffic. In this work, each sender node encodes packet using RLNC with MGM with the aim to provide more protection to I frames. In MGM, mixing set size number of I packets (Intra frames) are encoded together in one generation and enough number of copies is forwarded over the network. In order to provide more protection to packets of I frames, I packets are encoded with P (Predictive frames) packets in another generation and enough copies of mixed IP packets are generated and forwarded over the network. Similarly, I and P packets are encoded with B (Bidirectional frames) packets and enough copies of IBP mixed packets are generated and forwarded over the network. In this thesis work, simulations are carried out by changing protocol parameters and its effects on network parameters and performance parameters are analyzed. Simulation results confirm with intuition that the performance get enhanced using Random Linear Network Coding with MGM.

49-54

Authors: M. H. Joshipura

Ionic liquids are considered as green solvents. They are useful in many aspects. Thermodyanmic data are required for proper simulation of the processes. Prediction of properties using Cubic Equations of State (CEOS) is an attractive option as it requires only pure component data. Ionic liquids have very low vapor pressure and hence estimating vapor pressure is very challenging. Zero pressure fugacity approach was used in the present work. For ten ionic liquids vapor pressure predictions were carried out using Patel-Teja equation of state. This CEOS was used with six different cohesion factor models. Optimized parameters were generated for all the IL's for six cohesion factors and are provided in the paper. Generalization was also done using acentric factor and mass connectivity index for all the models and the comparison was done. It was found that exponential form of cohesion factor gave the highest accuracy for generalized model.

59-62

Authors: Rohit Samadhiya & P. K. Singhal

In this paper the microwave balun with defected ground structure has been presented. Here in the ground the slots of different sizes and of shapes have been cut to show the transition of electric field between the microstrip and slots in the ground. This structure has been designed at 2.7GHz frequency; the return loss (S11) is obtained 18dB, bandwidth of the proposed structure is obtained to 54MHz and the phase difference between the balanced ports is 180 degree.

81-90

Authors: M. Suhanya, M. Thirumarimurugan & T. Kannadasan

Owing to the difficulty in disposal of tyres and environmental pollution due to accumulation of waste tyres, pyrolysis is carried out as an alternative, efficient and environmental valorisation process, rather than combustion-inceneration which primarily is characterized as a destructive one. Pyrolysis can be considered as a non-conventional method for tyre recycling, which seems to be very appropriate for complex materials, such as tyres. This technology could not only reasonably and effectively dispose waste tyre and tube without pollution, but also is effective in producing fuel that can reduce energy crisis. Thermogravimetry analysis reveals that the pyrolysis of tire rubber at atmospheric pressure starts at a temperature around 250oC and finishes at a temperature of about 550oC. In general, by pyrolysing waste tire three fractions are obtained: solid residue (around 40 wt.%), liquid fraction (around 50 wt.%) and gas fraction (around 10 wt.%). The general trend is an increase in yields of liquid and gas fractions as the temperature increases. From the works devoted to tire pyrolysis, which are investigated on the generation of liquid fuel results that derived liquids are a complex mixture of organic compounds containing a lot of aromatics.

105-110

Authors: Hamsa K, Anusha Ramesh & Jayasimha SR

The DDN Web Object Scaler (WOS) is a revolutionary object-based, cloud storage system that addresses the needs of content scale-out and global distribution. At its core is the WOS object clustering system, intelligent software that allows a massively scalable content delivery platform to be created out of small building blocks, enabling the system to start small, and easily grow to a multi-Petabyte scale Objects stored in the WOS cluster are managed by policies which determine where the data should physically reside. WOS policies dictate content distribution within the cluster. Using policy-based content distribution with WOS, organizations can easily create disaster recover sites, place content close to where it will be accessed to improve performance and latency, or share content across the globe. One of the most unique features of WOS is that it maintains data location intelligence across the WOS cluster and minimizes object access latency, one of the biggest issues in cloud computing today. With this built-in intelligence, WOS ensures that data is always served back to clients from the “closest” location (i.e. with the lowest possible latency) and that bandwidth costs between zones are kept in check. The specifics of how WOS determines the closest instance of data is the topic of the remainder of this document.

117-124

Authors: N. Sumi & R. Malathy

This paper describes the optimum level of replacement for strength and workability of concrete for pavement by replacing different percentage of fly ash and steel slag by weight of cement and fine aggregate for a mix of M40 grade concrete. Hence the study is made on effect of fly ash and steel slag on the performance of various parameters of concrete so as to produce an economical concrete for rigid pavements. An experimental investigation has been made to utilize the achieved flexural strength of concrete in the rigid pavement design which is greater than the required flexural strength as per IRC: 58-2002. Pavement design results are verified with Analysis software. The main objective of the project is to find out alternative materials for road pavements to meet the demands of bitumen for the upcoming years, to provide adequate serviceability at minimum cost, to make the eco friendly roads with safety, and speed for the flow of traffic. In this investigation, an attempt has to be made to determine the feasibility of industrial waste products such as steel slag and fly ash use in base layer of concrete road pavements.

135-142

Authors: Bimal Garg & Akash Agrawal

Rectangular flat panel directional device with putative metamaterial cover at resonating frequency 2.292 GHz shows impressive increment in bandwidth and reduction in size as compared to lone flat panel directional device. Putative metamaterial cover improves bandwidth by 193%, cut down size by 32% and reduces return loss by 200%. Double negative left handed metamaterial structure was introduced as a cover to the rectangular flat panel directional device at a height of 3.2mm from the ground plane. The purpose of this work is to design a compact and efficient directional device with simultaneous negative permittivity and permeability or so-called LH MTM. Nicolson-Ross-Weir approach has been used for verifying the double-negative properties of the suggested double negative metamaterial cover.

151-154

Authors: Satyandra Singh Lodhi & P. K. Singhal

This paper propose a novel design of microstrip Yagi-Uda antenna at 2.45 GHz for ISM (industrial, scientific and medical) band application. The proposed antenna consists of pair of reflector, a driven element and three directors. The antenna had achieved directivity of 5.95 dBi, gain of 4.496 dB, return loss of -41.5 dB and high efficiency. It has been fabricated on the FR-4 substrate with dielectric constant of 4.4, loss tangent of 0.02 and substrate height 1.6 mm. Computer simulation technique (CST) MW studio software was used to simulate the design antenna. The parameter of antenna such as directivity, gain, bandwidth and antenna were analysis and also discussed.

161-168

Authors: NikunjYagnik & AnuragVerma

The meticulous knowledge of the kinematic chain is essential for the designer in mechanical engineering and importunate effort has made to know about kinematic chain as much as possible. The existing literature shows that methods have been reported by C.N. Rao and A.C.Rao to predict the performance and rate the kinematic chains and mechanism among several configurations. In the present work a methodology is used which is based on the influence of type of links, type of joints and type of loop present in a kinematic chain to predict the performance of kinematic chains without carrying out the dimensional synthesis. The work already reported has been used to explore the performance rating of catalogue of 8 – Link, 1 –degree of freedom simple jointed planar kinematic chain. For the whispered analysis required programme is developed in C language. Developed system is implemented to detect rating of independent suspension system mechanism and results shows that current methodology is superior.

177-186

Authors: MD. Arifur Rahman & Syed Muztuza Ali

Automatic control system has played a crucial role in the development of engineering and science and it has become an important and integral part of modern manufacturing and industrial processes. To get from a concrete controlled physical system there are fewsteps to be followed. First, a mathematical model of the physical system is made depending on the existing knowledge of classical physics and this mathematical model can take many forms. The second step in a control system design problem is to decide which desirable properties we want the physical system to satisfy. Very often, these properties can be formulated mathematically by requiring the mathematical model to have certain qualitative or quantitative mathematical properties. Together, these properties form the design specifications. The third, very crucial, step is to design, on the basis of the mathematical model of the physical system, and the list of design specifications, a mathematical model of the physical controller device. The problem of getting from a model and a list of design specifications to a model of a controller is called a control synthesis problem. In this paper, a state-space model has been derived from a type one transfer function plant model. Then the plant’s dynamic characteristics have been analyzed and simulated. After that a state feedback controller using the LQR method and finally a rigorous simulation analysis has been done with the designed LQR system with non-zero initial state with zero external inputs.

193-198

Authors: Madeva Nagaral, V Auradi & Ravishankar M K

Aluminium metal matrix composites (MMCs) have gained importance in various industries because of their good mechanical properties such as wear resistance, low density, high strength and good structural rigidity. Aluminium MMCs are preferred in the fields of aerospace, military, automotive, marine and in many other domestic applications. In this study, it is intended to develop and study the mechanical behaviour of Al6061/Al2O3/Graphite reinforced hybrid Aluminium metal matrix composites. The composite is prepared by using Liquid Metallurgy Route (Stir Casting Technique), although powder metallurgy produces better mechanical properties in MMCs, liquid state has some important advantages such as better matrix particle bonding, easier control of matrix structure, simplicity, low cost of processing, nearer to net shape and wide selection of material. Al6061 alloy is taken as the base matrix to which Al2O3 and graphite particulates are used as reinforcements.6 wt% of Al2O3 is added to the base matrix, whereas, the graphite is varied from 2,4 and 6 wt% into the base matrix. For each composite, re-inforcement particles are pre-heated to a temperature of 200ºC and then dispersed in steps of 3 into the vortex of molten Al6061 alloy to improve wettability and distribution. The hardness and tensile properties of prepared composites were examined. Mechanical properties like hardness and tensile strength of Al6061 alloy was increased by addition Al2O3 particles. The Micro-Vickers hardness of the Al6061-6wt% Al2O3 was found to decrease with addition of graphite content in the composite but the effect of graphite content on tensile strength of the composite was less.

1-6

Authors: A. D. Bhosale & Marathe Dagadu Mitharam

Computers are commonly used items in many areas. The computer is one of the most powerful forces in organization today. Computers impacted in organization in many ways. Organization received some benefits using computer (Greater Efficiency, Higher Quality products, Better service, Recreational and educational benefits, Better information retrieval, fast working, Accuracy etc) In this paper show some benefits as well as positive impact of computers on organization.

9-12

Authors: Nempal Singh, Jitendra Singh, Sachin Kumar, Manoj Kumar, Ansul Gaur & Kapil Sirohi

In the present paper the thin film of CdS and Polyaniline has been developed by vacuum evaporation technique. The prepared thin films then deposited onto glass as well as metallic substrates. The glass substrate was cleaned in aquaregia, washed in distilled water and isopropyl alcohol (IPA). These prepared samples were then subjected for the electrical measurements by employing Keithley electrometer. In PANI/ CdS junction the conduction of charge across the junction is typically a mixture of electron from n-CdS side a polaron and bipolaron from p-Pani side. The n-CdS and p-Pani heterojunction also holds the promises of being studied and converted in to an active device. The low value of fill factor and conversion efficiency can be attributed to the polycrystallinity of the CdS thin film and vacuum deposited Pani thin film, as they do not make an extremely sharp perfect heterojunction. Also the substrate has a strong influence on the surface morphology of the films.

21-34

Authors: Krishna Prasanth K & Muruganantham P

In launch vehicle structures design, importance is given to lightweight with high load bearing capacity design, so the factor of safety is kept low compared with ground-based structures and at the same time maintaining high reliability. This demands very accurate analysis of structural elements for launch vehicle. The main criteria are lightweight, ease of fabrication, lower cost and at the same time meeting the strength and stiffness requirements. The commonly used launch vehicle structure is the closely stiffened structure in which the structure consists of 90 or 120 no’s of stringers riveted onto a 1.2mm thick skin and a few number of bulkheads. In this type of structures, thin shell can buckle or cripple at a load much lower than the buckling strength of stringers. In order to overcome this, integrally stiffened structures such as isogrid structures is chosen. Isogrid is the name given to integrally, grid stiffened shell and structures in which the grids form an equilateral triangle pattern. The isogrid structure can withstand both compressive and bending loads and also offers lower weight and higher structural efficiency. A typical inter tank structure that was preliminary designed using closely stiffened shell structure has been identified for study. This is a cylindrical structure having a diameter of 4.0m and a height of 2.75m which should safely withstand the loads expected on it during different phases of flight. It should safely carry the accessories needed for the next stage separation. A detailed design analysis of this particular launch vehicle structure using integrally stiffened construction is done both theoretically and also the results are verified by using FEA packages. The scope of study is to make a detailed design through FE analysis.

45-52

Authors: G. Brindha

Multi Carrier Code Division Multiple Access (MC-CDMA) is an attractive choice for high speed wireless communication as it avoids the problem of Inter Symbol Interference (ISI) and also exploits frequency diversity. In order to support multiple users with high speed data communications, the MC-CDMA technique is used to address these challenges. MC-CDMA experiences severe multipath fading which badly affects its performance. When transmission over fading channel multi-cell interference occurs and this degrades the performance of the system. This paper specially analyzes the BER performance under Rayleigh fading channel conditions of MC-CDMA in presence of AWGN (Additive White Gaussian Noise) using BPSK modulation for different number of subcarrier, different number of users using MATLAB program, and finally the paper also presents a comparison between simulated results, which shows the reduction in BER performance.