In this study, an in-house multi-dimensional code has been developed which simulates the combustion of n-heptane in a Homogeneous Charge Compression Ignition (HCCI) engine. It couples the flow field computations with detailed chemical kinetic scheme which involves the multi-reactions equations. A chemical kinetic scheme solver has been developed and coupled for solving the chemical reactions an...

in this paper, the effects of input temperature and compression ratio on the net output work and efficiency of the air standard cycles, i.e. atkinson cycle, diesel cycle and otto cycle are analyzed. we assumed that the compression and power processes are adiabatic and reversible and any convective, conductive and radiative heat transfer to cylinder wall during the heat rejection process may be ...

Image compression is a fast paced and dynamically changing field with many different varieties of compression methods available. Wavelet transform techniques currently provide a promising approach to image compression and concentrate on achieving higher compression ratio without sacrificing the quality of the image. In image compression, the choice of wavelet depends on the image content. The q...

In image based rendering (IBR), a 3D scene is recorded through a set of photos which is then rendered to form novel views. Compression is essential to reduce the huge data amount of IBR. In this paper, we examine three categories of IBR compression algorithms: the block coder, the reference coder and the wavelet coder. We examine both the compression efficiency and the capability to render the ...

Medical images show a great interest since it is needed in various medical applications. In order to decrease the size of medical images which are needed to be transmitted in a faster way; Region of Interest (ROI) and hybrid lossless compression techniques are applied on medical images to be compressed without losing important data. In this paper, a proposed model will be presented and assessed...

An image compression algorithm using JPEG-LS and cubic spline interpolation (CSI) is presented in this paper. The CSI is developed in order to subsample image data with minimal distortion and to achieve image compression. It has been shown in literatures that the CSI can be combined with the transform-based image compression algorithm to develop a modified image compression codec. The compressi...

Images include information about human body which is used for different purposes such as medical, security and other plans. Compression of images is used in some applications such as profiling data and transmission systems. Regard to importance of images information, lossless or lossy compression is preferred. Lossless compressions are JPEG, JPEG-LS and JPEG 2000 is few well-known methods for l...

The goal of image compression is to remove the redundancies for minimizing the number of bits required to represent an image while any type of compression like DWT,DCT,DFT, steganography works by embedding the secret data in redundancies of the image in invisibility manner. In this paper we increase image compression is done by hybrid (DCT+DWT) transform. MATLAB programs were written for DCT,DW...

Medical image compression is essential for huge database storage in various hospitals and data transfer for diagnosis. Wavelets give one such approach for compression purpose. A wavelet is a wave-like oscillation with an amplitude starts from zero, increases, and then decreases again to zero. Compression techniques are divided into lossless and lossy techniques. Lossless technique involves exac...