This paper presents the analysis results of R429A, R430A, R431A and R435A as drop in substitute for R152a at various evaporating temperature with condenser temperature 30°C, 40°C and 50°C. A theoretical study of thermodynamic properties such as pressure, density, and specific volume, latent heat of vaporization compression index, and critical values are done. The theoretical performance of vapo...

A fully-integrated Multi-Band PA using 0.25 μm SiGe:C process with an output power of above 25 dBm is presented. The behaviour of the amplifier has been optimized for multi-band operation covering, 2.4 GHz, 3.6 GHz and 5.4 GHz (UWB-WiMAX) frequency bands for higher 1-dB compression point and efficiency. Multi-band operation is achieved using multi-stage topology. Parasitic components of active ...

In video compression, image pre-processing is used to improve the overall compression performance. A key requirement of any such system is the ability to remove noise and other higher frequency details while preserving the visual quality of the images. This paper presents a new approach to pre-filtering, based on area morphology. Both the standard area and a new constraint, based on the power w...

Explosive-driven magnetic-flux-compression generators have been around since the early 1950s, when they were independently invented in the United States and the Former Soviet Union. Interest in these generators has been cyclic over the years and we appear to be in the upswing of renewed interest, not only in the US and Russia but other countries as well. Therefore, it was decided that it was ti...

conclusions after kyphoplasty, her pain was immediately resolved, vertebral body height was restored to normal, and pain score was reduced from 8 to 1. she was discharged with a normal neurological examination and good general condition, and returned to her normal life. in this case, balloon kyphoplasty resulted in the restoration of the vertebral body height, decrease in pain, and returning to...

A log-domain current-mode quadrature sinusoidal oscillator based on lossless integrators is presented. The circuit is a direct realization of a first-order differential equation for obtaining the lossy and lossless integrators. Each of the log-domain lossless integrators is realized by using only NPN transistors and a grounded capacitor for achieving low-power and fast response. The proposed os...

Data compression plays a vital role in multimedia devices to present the information in a succinct frame. Initially, the DCT structure is used for Image compression, which has lesser complexity and area efficient. Similarly, 2D DCT also has provided reasonable data compression, but implementation concern, it calls more multipliers and adders thus its lead to acquire more area and high power con...