Due to the growing demand for higher bandwidth, employing optical devices instead of electronic devices in data transmission systems has attracted much attention in recent years. Optical switches, modulators and wavelength converters are a few examples of the required optical devices. CMOS compatible fabrication of these devices, leads to much more growing of this technology. Optical pulse comp...

An optimized medical image compression algorithm based on wavelet transform and improved vector quantization is introduced. The goal of the proposed method is to maintain the diagnostic-related information of the medical image at a high compression ratio. Wavelet transformation was first applied to the image. For the lowest-frequency subband of wavelet coefficients, a lossless compression metho...

-------------------------------------------------------------------ABSTRACT------------------------------------------------------------This paper focuses on improving the Image compression ratio and having 100% quality factor. The major emphasis has been on Arithmetic Coding, its principle has been applied to get the wanted results i.e. higher compression ratio than JPEG on an average quality f...

Microarray technology is a new and powerful tool for concurrent monitoring of large number of genes expressions. Each microarray experiment produces hundreds of images. Each digital image requires a large storage space. Hence, real-time processing of these images and transmission of them necessitates efficient and custom-made lossless compression schemes. In this paper, we offer a new archi...

Data compression has been widely applied in many data processing areas. Compression methods use variable-length codes with the shorter codes assigned to symbols or groups of symbols that appear in the data frequently. There exist many coding algorithms, e.g. Elias-delta codes, Fibonacci codes and other variable-length codes which are often applied to encoding of numbers. Although we often do no...

In this study, operation of compressor station has been investigated by exergy approach. Exergy analysis is a thermodynamic method which shows the irreversibility of a system quantitatively. Gas compressors are used to compensate the pressure drop along the gas pipeline significantly. The compression process causes temperature rise of gas; in this regard gas cooler is applied to reduce the temp...