Informatics Publishing Limited

N. Sathish Kumar ¹, K. Kannan ², S. Sendhil Kumar ³

Affiliations
1 PSG College of Technology, Coimbatore-641004, IN
2 Dept. of Production Engineering, PSG College of Technology, Coimbatore-641004, IN
3 Aeronautical Engineering, Karpagam Institute of Technology, Coimbatore-641105, IN

Abstract

It is essential that aerodynamics can be taken in to account during the design of cars as an improved aerodynamics in car would attain higher speeds and more fuel efficiency which leads to less fuel consumption and vehicle stability and reduces shortage of fuel. In this paper the external aerodynamics of a commercial car model was investigated numerically and validated the results experimentally with wind tunnel. The objective of the current work is to check the drag and lift co-efficient of model, as well as pressure distribution of the commercial car model in wind tunnel, second to develop virtual wind tunnel environment and conduct trials. In this paper 1:14 scale down car model is used and by applying reverse engineering concept CAD (Computer Aided Design) data is extracted from the scale down model for Computational Fluid Dynamics (CFD) analysis. ANSA and T-grid is used as pre-processor and Fluent as solver for CFD analysis.

Keywords

CFD, Reverse Engineering, Wind Tunnel Test.

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M. Kasiselvanathan ¹, N. Sathish Kumar ¹

Affiliations
1 Department of ECE, Sri Ramakrishna Engineering College, Coimbatore - 641022, Tamil Nadu, IN

Abstract

Objective: Multiple Input Multiple Output (MIMO) low complexity CHEMP (Channel Hardening Exploiting Message Passing) receiver which utilizes the channel hardening in the large scale MIMO channel to reduce the complexity. Methods: The Channel Hardening refers that the off diagonal elements of HTH matrix become progressively weaker than the diagonal elements because of the channel gain matrix H size increases. It is used for detection and estimation. The proposed receiver uses Message Passing Detection (MPD) algorithm and the estimation HTH matrix. Findings: Hence, the proposed receiver gives better performance than the Minimum Mean Square Error (MMSE) and Subspace Marginalization with Interference Suppression (SUMIS) detectors since the MPD detection algorithm uses only the matrix multiplication and it does not need the matrix inversion. Improvements: The optimized Low Density Parity Check (LDPC) codes are used to provide the considerable improvement than LDPC cods.

Keywords

BER, Channel Hardening, CHEMP Receiver, MIMO, MPD

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M. J. Venkatesan ¹, N. Sathish Kumar ¹, C. Vijayalakshmi ¹

Affiliations
1 Department of Ophthalmology, Melmaruvathur Adhiparasakthi Institute of Medical Sciences, Melmaruvathur, Kanchipuram District, Chennai – 603319, Tamil Nadu, IN

Abstract

Objective: To assess the fundus changes and incidence of various peripheral retinal degeneration associated with Myopia and to correlate these changes with the age of the patients. Materials and Methods: Randomised Prospective observational study of 100 cases of myopia (less than or equal to -6D: 50 cases and more than -6D: 50 cases) all the patients detailed history was recorded and subjected to intensive examination of both Anterior segment and posterior segment of the eye. The various fundus features and pathological lesions in the different degrees of myopia were noted and analysed. Findings: Females were comparatively affected more. Majority of the patients did not have significant family history. Majority of the cases showed some fundus changes more common were tessellated fundus. Axial length is relatively increased in higher degrees of myopia. Peripheral retinal degeneration are more common in moderate to higher degrees of myopia. Applications: The degenerative changes of fundus is commonly seen in moderate to high degrees of myopia whereas in our study it is evident in lesser degree also. Hence thorough examination of peripheral fundus using indirect ophthalmoscope for all cases of myopia will help in early diagnosis and treatment.

Keywords

Better Prognosis, Early Intervention, Indirect Ophthalmoscopy, Meticulous Examination, Pick up Complications

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