Fractal image compression:Recent technique based on the representation of an image

Storing an image on a computer requires a very large memory. This problem can be averted by the use of various image compression techniques. Most images contain some amount of redundancy that can be removed when the image is stored and then replaced when it is reconstructed.

Fractal image compression is a recent technique based on the representation of an image. The self-transformability property of an image is assumed and exploited in fractal coding. It provides high compression ratios and fast decoding. Apart from this it is also simple and is an easily executable technique.

PERCEPTIVE COMPUTING:A computer with perceptual capabilities

Survival of animal depends highly on developed sensory abilities. Like wise human recognition depends on highly developed abilities to perceive, integrate, and interpret visual, auditory, and touch information. Also we have no doubt that if computers had even a small fraction of the perceptual ability of animals or humans, then they would be much more powerfull.Adding such perceptual abilities to computers would enable computers and humans to work together more as partners. Perceptive Computing (Blue Eyes) project aims at creating computational devices with the sort of perceptual abilities that people take for granted. Blue Eyes uses non-obtrusive sensing technology

Computer Clothing:Digital clothes that able to perform some of the PC functions

There is a major movement going on in the electronics and computer industries to develop wearable devices for what’s being called Post-PC era. We are now at the dawn of that era and some of these devices are already making their way to the consumer market .Computerized clothes will be the next step in making computers and devices portable without having to strap electronics into our body. These digital clothes will able to perform some of the PC functions. These devices are small in size and portable. This apparel can be used to read our heart rate and breathing. The LED monitors could even be integrated into this apparel to display text and images.

microprocessor based auto synchronization

The manual method of synchronization demands a skilled operator and the method is suitable for no load operation or normal frequency condition. under emergency condition such as lowering of frequency or synchronizing of large machines a very fast action is needed, which may not be possible for a human operator. Thus there is a need of autosynchroniser in a power station or in an industrial establishment where generator are employed. This paper describes a microprocessor based set up for synchronizing a three phase alternator to a busbar. Also existing methods of synchronization are mentioned.

Wavelet Transforms:one of the important signal processing developments in the last decade

Wavelet transforms have been one of the important signal processing developments in the last decade, especially for the applications such as time-frequency analysis, data compression, segmentation and vision. During the past decade, several efficient implementations of wavelet transforms have been derived. The theory of wavelets has roots in quantum mechanics and the theory of functions though a unifying framework is a recent occurrence. Wavelet analysis is performed using a prototype function called a wavelet. Wavelets are functions defined over a finite interval and having an average value of zero. The basic idea of the wavelet transform is to represent any arbitrary function f (t) as a superposition of a set of such wavelets or basis functions. These basis functions or baby wavelets are obtained from a single prototype wavelet called the mother wavelet, by dilations or contractions (scaling) and translations (shifts). Efficient implementation of the wavelet transforms has been derived based on the Fast Fourier transform and short-length ‘fast-running FIR algorithms’ in order to reduce the computational complexity per computed coefficient.

Energy transmission system for an artificial heart- leakage inductance compensation

A power supply system using a transcutaneous transformer to power an artificial heart through intact skin has been designed. In order to realize both high-voltage gain and minimum circulating current, compensation of leakage inductances on both sides of a transcutaneous transformer is proposed. A frequency region which realizes the robustness against coupling coefficient and load variation is identified. In this region, the converter has inherent advantages such as zerovoltage switching (ZVS) or zero-current switching (ZCS) of the switches, high-voltage gain, minimum circulating current, and high efficiency.

Artificial heart, energy transmission system, high efficiency, high-frequency converter, high-power density, high-voltage gain, inductance compensation, soft-switched converter, transcutaneous transformer, zero-current switching (ZCS), zero-voltage switching (ZVS).

Integrated Gate Commutated Thyristor (IGCT)

The Integrated Gate Commutated Thyristor (IGCT) combines the advantages of the hard driven GTO thyristor, including its dramatically improved turn- off performance, with technological breakthroughs at the device, gate-drive and application levels. Homogenous switching area of the IGCT up to the dynamic avalanche limits. Snubber circuits are no longer needed. Improved loss characteristics allow high frequency applications extending into the kHz range. A new IGCT device family with integrated high- power diodes has been developed for applications in the 0.5-6 MVA range, extending to several 100 MVA with series and parallel connections. A first 100 MVA inverter based on the IGCT has been in commercial operation and confirms the very high level of reliability of this new technology. Other new application using the IGCT platform includes ABB’s new ACS1000 drive for medium voltage applications.