International Journal of Engineering and Manufacturing (IJEM)

IJEM Vol. 5, No. 4, Nov. 2015

Cover page and Table of Contents: PDF (size: 232KB)

Table Of Contents


Enhancement on Sound Transmission Loss for Various Positioning of Inlet and Outlet Duct of the Muffler

By Amit Kumar Gupta Ashesh Tiwari

DOI:, Pub. Date: 8 Nov. 2015

Muffler acts as noise reduction element on exhaust system. Noise from an automotive application is the major source of noise pollution. Here the transmission loss of central inlet and central outlet muffler of single expansion chamber has been compared and validated in three methods namely transfer matrix method, finite element analysis and an experimental method for this purpose an experimental setup has been built up which is based on two load method. Several researchers have worked in the area of noise attenuation on central inlet by changing the position of outlet as side outlet but no one emphasizes on offset of the central inlet and central outlet position. Thereafter the finite element analysis tool Ricardo wave 1-D and comsol multiphysics is used to evaluate transmission loss for various offset position of inlet and outlet duct of the muffler. The very purpose to improve the acoustic performance of central inlet with offset outlet pipe by measuring transmission loss of offset inlet with offset outlet with various positions by keeping same space. Finite element analysis shows that higher attenuation can be achieved by increasing offset distance of central inlet & outlet outlet towards radial direction of the expansion chamber with the variation of 0.2r, 0.4r and 0.6r. Here 'r' is radius of single expansion chamber. The result shows that high transmission loss can be achieved by increasing the offset radial distance of the inlet pipe and outlet pipe. Further higher attenuation can also be achieved in case of fixed the distance of offset inlet and outlet at 0.6r by rotating the offset outlet which is also offseted at 0.6r distance by 0o, 45o, 90o, 135o and 180o. On ward rotation from remaining 180o to 360o the behavior of wave propagation will be same what has been reflected between 0o to 180o. Transmission loss maximizes when the offset outlet is loacted at 90o. It clearly reveals that optimization can be achieved by using finite element analysis tool by using virtual protyping. 

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Analysis of Late Blight Disease in Tomato Leaf Using Image Processing Techniques

By Megha P Arakeri Malavika Arun Padmini R K

DOI:, Pub. Date: 8 Nov. 2015

Tomato (Lycopersicon esculentum L.) is one of the most widely grown crops in the world. This crop is easily prone to various diseases. One such disease is late blight, caused by the fungus Phytophthora infestans. The first symptoms of late blight on tomato leaves are irregularly shaped, water soaked lesions, which are typically found on the younger leaves of the plant canopy. During humid conditions, white cottony growth may be visible on the underside of affected leaves. As the disease progresses, lesions enlarge causing leaves to brown, shrivel and perish. Hence in the present paper, a novel computer vision system has been proposed for detection and analysis of late blight disease. The proposed system implements thresholding algorithm to classify the leaf as diseased or healthy. Later it uses K -means clustering algorithm for analyzing late blight disease. The experiment was carried out on leaves of tomato collected from various plantations. The accuracy, sensitivity and specificity of the developed system in analyzing the late blight disease are 84%, 85% and 80% respectively.

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Design of Low Power Current Mode Square-Root Circuit

By Bindu Thakral

DOI:, Pub. Date: 8 Nov. 2015

Analog circuits have been viewed as a voltage dominated type of signal processing. With the advent of CMOS technology, shrinking feature size, and reduction of supply voltage a new class of circuits developed: current-mode circuits. Among current-mode circuits "Translinear circuits" is one of the important and emerging research interests for low power analog designers. It is the practical means of implementing nonlinear signal processing functions. The performance of analog circuits strongly depends upon techniques used to exploit the characteristics of the transistors. In this paper, using exponential current-voltage relationship of MOS transistor when biased in subthreshold-mode, a square-root circuit is proposed. The circuit simulations were carried on TSMC 0.18 micrometer technology using ELDO Simulator. 

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