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Volume 4 ~ Issue 5
Research Article  open access
Effect of heat source/sink on MHD Mixed convection Boundary layer flow on a vertical surface in a porous medium saturated by a nanofluid with suction or injection
Mohammad Mehdi Keshtkar|| Neda Esmaili || Mohammad Reza Ghazanfari
Iran
Research Inventy: International Journal of Engineering & Science 2014, Volume 4 ~ Issue 5 (May 2014)

Paper Index :: : 07.4721/045001011
Abstract

The effect of heat source/sink on steady two-dimensional laminar MHD mixed convection boundary layer flow past a vertical permeable surface embedded in a porous medium saturated by a nanofluid is performed in this study. Numerical solutions of the similarity equations are obtained using the shooting method. Three types of metallic or nonmetallic nanoparticles, namely Copper (Cu), Alumina (Al2O3) and Titania (TiO2) are considered by using a water-based fluid to investigate the effect of the solid volume fraction or nanoparticle volume fraction parameter of the nanofluid. The numerical results of the skin friction coefficient and the velocity profiles are presented and discussed. It is found that the imposition of suction is to increase the velocity profiles and to delay the separation of boundary layer, while the injection parameter decreases the velocity profiles. On the other hand, the range of solutions for the injection case is largest for Al2O3 nanoparticles and smallest for Cu nanoparticles.

Key words:Boundary Layer, Nanofluid, Mixed Convection, Permeable Surface, Porous Medium, Magnetic field


Research Article  open access
A New Approach to analysis of t-domain and f-domain in A Nose-Wheel Steering of Medium-Haul Air-Craft
Ajoy Chanda
India
Research Inventy: International Journal of Engineering & Science 2014, Volume 4 ~ Issue 5 (May 2014)

Paper Index :: :07.4721/045012015
Abstract

Electromechanical nose-wheel steering systems give the Medium-haul air-crafts the needed maneuverability and durability. These air-crafts are of intermediate size. They must be able to utilize small air-fields, having little or no service and maintenance facilities. During take-off, the nose-wheel steering keeps proper heading. Feedback from the nose-wheel heading is compared with the pilot command to generate the error signal. This signal is amplified and applied to a magnetic particle clutch, which activates the rotation of the wheel-heading. The paper deals with nose-wheel steering of Medium haul aircraft. The design specifications are conflicting with each other. To keep the steady state error at a low value the forward path gain must be high. At the required value of the gain, the system becomes unstable. Addition of rate feedback makes the system stable but it fails to satisfy the transient requirement. The overshoot remains at a high value even if the coefficient of rate feedback is varied over a wide range. The required t-domain performance could be achieved by the addition of weighted acceleration feedback. The specifications could be fulfilled by suitably choosing the coefficients of rate and acceleration feedback. Starting from the block diagram, the mathematical model has been developed and the analytical treatment has been made by indigenously made computer program. The results have been verified by using MATLAB-tools.

Keywords:Nose-wheel, Medium-haul air-craft, Rate & acceleration feedback, Steady state error, Overshoot.


Research Article  open access
Doubly Secured Authentication Scheme using RKO technique of Visual Cryptography
Mrs. Moushmee Kuri || Dr. Tanuja Sarode
India
Research Inventy: International Journal of Engineering & Science 2014, Volume 4 ~ Issue 5 (May 2014)

Paper Index :: :07.4721/045016020
Abstract

Authentication using passwords has become old and is not reliable with respect to security. Passwords if too simple can be easily cracked and if too complex it's difficult to remember them. Password storing and matching use different hashing/encryption techniques. However they require complex algorithms for encryption and decryption, Visual cryptography is a technique which provides confidentiality without any cryptographic knowledge or complex computations. Visual information such as photo and signature can be encrypted by decomposing it into several images, called shares; in such a way that decryption can be done by human visual system with stacking of the shares. The RKO technique which is a hybrid technique of VC divides the image into two shares, one random share and one key share. When these two shares are XORed pixel by pixel the generated is same as the original image in terms of quality. In this paper we propose a doubly secured authentication scheme which uses RKO technique to login. This scheme creates shares of photo and signature image and uses these shares to login the system. This scheme improves the security level of the existing schemes.

Key words—Visual Cryptography, Authentication, Shares, Bank login, Image Encryption, RKO technique.


Research Article  open access
Dynamic Analysis of Timing Chain System of a High Speed Three Cylinder Diesel Engine
R. V. Mulik||Prof. M. M. Joshi||Dr. S. Y. Gajjal||S. S. Ramdasi ||N. V. Marathe
India
Research Inventy: International Journal of Engineering & Science 2014, Volume 4 ~ Issue 5 (May 2014)

Paper Index :: :07.4721/045021025
Abstract

The current trend in automotive industry is to achieve compact, efficient, reliable systems. Engine timing drives used in engines are one of the most critical systems. Timing belts are subjected to excessive elongation and wear, while timing gears contribute excess mass and inertia in the system. Hence timing chains are preferred widely, in various high performance engines, both in gasoline and diesel engines. Chain drives are easy to assemble and adjust, highly efficient, durable, reliable, compact and capable of attaining a wide range of power and speed capacities. In spite of these advantages their complex dynamic behavior is not well researched. The major objective of the current work is to develop timing chain drive for a high speed three cylinder diesel engine and investigate about its durability. The scope of the work includes developing a simulation model in suitable simulation software and its dynamic analysis. The results are expressed in terms of parameters such as contact forces and normal forces between different components and link tension forces etc

Key words—Chain Drive, chain tension.


Research Article  open access
Co-Operative Multiple Replica Provable Data Possession for Integrity Verification in Multi-Cloud Storage
Mr.Susheel George Joseph
India
Research Inventy: International Journal of Engineering & Science 2014, Volume 4 ~ Issue 5 (May 2014)

Paper Index :: :07.4721/045026031
Abstract

Many storage systems rely on replication to increase the availability and durability of data on untrusted storage systems. At present, such storage systems provide no strong evidence that multiple copies of the data are actually stored. Storage servers can collude to make it look like they are storing many copies of the data, whereas in reality they only store a single copy. We address this shortcoming through multiple-replica provable data possession (MR-PDP): A provably-secure scheme that allows a client that stores t replicas of a file in a storage system to verify through a challenge-response protocol that each unique replica can be produced at the time of the challenge and that the storage system uses t times the storage required to store a single replica. MR-PDP extends previous work on data possession proofs for a single copy of a file in a client/server storage system.

Key words—Data Possession, Homomorphic, Integrity, Multi-Cloud, Multi-Replica,Zero-Knowledge


Research Article  open access
Behavior on Shear Strengthening of Precraced/Repair RC
Continuous Beams Using CFRP Strips

M.B.S Alferjani||A.A. Abdul Samad||Blkasem. S Elrawaff|| N. Mohamad
Malaysia
Research Inventy: International Journal of Engineering & Science 2014, Volume 4 ~ Issue 5 (May 2014)

Paper Index :: :07.4721/045032044
Abstract

This paper presents the results of an experimental investigation for enhancing the shear capacity of reinforced concrete (RC) continuous beams using different CFRP wrapping schemes. A total of five concrete beams were tested and various sheet configurations and layouts were studied to determine their effects on ultimate shear strength and shear capacity of the beams. One beam was kept as control beams, while other
beams were precracked and repaired with CFRP strips (i.e. precracked/repaired) with four or three sides bonding. Tests result shows that the effectiveness and shear capacity of the CFRP strengthened specimens. The shear enhancement of the CFRP strengthened beams varied between 18% and 44% over the control beam. This study confirms that the CFRP strip technique significantly enhances the shear capacity of reinforced concrete shear beams. Two prediction models available in literature were used for computing the contribution of CFRP
strips and compared with the experimental results.

Key words—CFRP, Continuous Beam, Shear Strengthening


Research Article  open access
Modelling, Simulation and Analysis of Custom Power Devices for Improve Power Quality
S.Radha Krishna Reddy || G.Venugopal || P.Shankar Babu || Ch.Kamal
India
Research Inventy: International Journal of Engineering & Science 2014, Volume 4 ~ Issue 5 (May 2014)

Paper Index :: :07.4721/045045050
Abstract

This paper describes the modeling, simulation and analyzes of custom power devices for
compensating voltage sag and swell conditions in three phase systems. Faults occurring in power distribution systems or facilities in plants cause the voltage sag or swell. If a fault occurs, it can damage the power system or user's facility. Sensitivity to voltage sags and swells varies within different applications. For sensitive loads (PLC's, paper mills etc.), even voltage sags of short duration can cause serious problems in the entire system.
Normally, a voltage interruption triggers a protection device, which causes shutdown of the entire system. In order to mitigate power interruptions, this paper proposes a scheme for voltage sag support based on a pulse width modulated autotransformer. The proposed scheme is able to quickly recognize the voltage sag or swell condition, and it can correct the voltage by either boosting the input voltage during voltage sag events or reducing the voltage during swell events.

Key words—DSTATCOM, Voltage sag, swell, power quality, PSCAD, PWM.