Informatics Publishing Limited

P. Vetrivelan ¹, A. Kandaswamy ²

Affiliations
1 Sri Ramakrishna Institute of Technology, IN
2 Bio-Medical Engineering Department, PSG College of Technology, Coimbatore, Tamilnadu, IN

Abstract

This paper discuss the compression of an image using lifting scheme to implement SPIHT (set partitioning of hierarchical trees). The SPIHT algorithm uses dynamic data structure that does not make it possible for use in a hardware system. Here the implementation of SPIHT algorithm using lifting scheme in system c is done, so that it becomes suitable for implementation in FPGA. The hardware implementation is done in a XILINX XC3S500E device.

Keywords

Discrete Wavelet Transform, SPIHT, Lifting Scheme, Image Compression.

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S. Allin Christe ¹, K. Malathy ¹, A. Kandaswamy ²

Affiliations
1 Department of Electronics and Communication Engineering, PSG College of Technology, Coimbatore, IN
2 Department of Bio-Medical Engineering, PSG College of Technology, Coimbatore, IN

Abstract

Medical image segmentation is the most essential and crucial process in order to facilitate the characterization and visualization of the structure of interest in medical images. Relevant application in neuroradiology is the segmentation of MRI data sets of the human brain into the structure classes gray matter, white matter and cerebrospinal fluid (CSF) and tumor. In this paper, brain image segmentation algorithms such as Fuzzy C means (FCM) segmentation and Kohonen means(K means) segmentation were implemented. In addition to this, new hybrid segmentation technique, namely, Fuzzy Kohonen means of image segmentation based on statistical feature clustering is proposed and implemented along with standard pixel value clustering method. The clustered segmented tissue images are compared with the Ground truth and its performance metric is also found. It is found that the feature based hybrid segmentation gives improved performance metric and improved classification accuracy rather than pixel based segmentation.

Keywords

K-Means, Fuzzy C-Means, Fuzzy Kohonen Means Clustering, Distance of Clustering, Von Dongen Index.

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Karthikeyan Subramanian ¹, A. Kandaswamy ¹, S. Mhahadevan ²

Affiliations
1 Dept. of Automobile Engg., Anna University, MIT Campus, Chennai, IN
2 Dept. of Product Development Engine Testing, Ashokleyland Technical Center, Chennai, IN

Abstract

The two cylinder diesel engines are most demanding product in Indian market for power genset and tractor applications. But major task faced by engine manufacturers all over the world is to upgrade running engine designs with minimum and cost-effective modifications to meet the next level of emission norms. This saves the precious lead time and investments. In addition uncomplicated design has to be sustained as far as possible while improving emissions. Further the basic desires of the end user in off-road market are good response, transient performance, better low end torque, best fuel efficiency and smooth operation of the engine besides best in class reliability. Additional requirements needed to sustain the market with higher power to weight ratio and increased life of the engine. Henceforth turbocharging applications for off-road diesel engines are promising solution for enhancing rated power, low speed torque, transient performance, optimized fuel efficiency and engine downsizing. A trade-off is required to match some incompatible design issues like overall dimensions, cost, emissions control and performance in order to sustain the existing design. Future diesel engine emission standards will restrict vehicle emissions, particularly nitrogen oxides. In the present work, performance improvement for 1.7L, 2 cylinder in-line naturally aspirated diesel engine with mechanical fuel injection pump for off-road application is developed to contain all needs of the market. Design up-gradation of this engine for Tier IV is made with minimal design changes by optimal combinations of fuel injection equipment. This includes proper optimization of performance with improvements in nozzle geometry, change in injector end pressure. But due to the increased fuel flow rates for improving the engine performance as well as emission reduction, there is also a requirement for increased air flow. Henceforth in this study air flow rate is simulated and discussed for selection of turbocharger and intercooler. Further elaborate design and analysis study is also done on cooled exhaust gas recirculation system for exhaust gas cooling efficiency, Diesel Oxidation catalyst, Selective Catalytic Reduction /Lean NOx Trap substrate selection for reduced pressure drop and maximum retention time for exhaust gas to achieve Tier IV norms in turbocharged intercooled two cylinder engine.

Keywords

Off-Road Diesel Engine, Injector, Turbocharger, Intercooler, Exhaust Gas Recirculation, Selective Catalytic Reduction.

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