Vol. 37 No. 1 (2005)

A special interferometric technique has been devised on the basis of rainbow refractometry without the use of an additional and delicate amplitude-splitting setup. This new technique was used for the characterization of plasma induced by a Q-switched Nd-YAG laser on zinc samples under atmospheric air pressure. An unmistakable signal of the density jump was detected simultaneously with the observation of the emission front signal. It was proved that the emission front and the front of the shock wave coincided and moved together with time at the initial stage of the secondary plasma expansion.…

The Hot Wire Cell PECVD method has been developed and successfully applied to grow the hydrogenated amorphous silicon (a-Si:H) thin films with a relatively high conductivity. The a-Si:H thin films were grown on the 7059 corning glass at a filament temperature of 800 oC. Ten percents silane (SiH4) gas diluted in hydrogen (H2) gas was used as gas source. In the hot wire cell PECVD method, reactant gases are decomposed as a result of reaction with a heated filament. The filament was placed parallelly with inlet gas system and outside of electrodes. The characterization results exhibited that the…

Maritime boundary between Indonesia and Singapore in the strait of Singapore has been defined by the territorial sea boundary treaty of 1973.In this treaty, geodetic datum of the geographic coordinates of six boundary points between Indonesia and Singapore are not explicitly stated. This paper investigates the possible datum for these coordinates, namely KERTAU48, KERTAU68, GENUK and SOUTH ASIA, and its impacts on the coordinates and location of boundary points. Related aspects are also discussed. Paper is sum up with some conclusions and recommendations.

This paper discusses performance evaluation of mobile cellular telecommunication system that is related to the handoff process. We focus our discussion to the system with fixed channel assignment and homogeneous traffic. Performance parameters we discuss in this paper are the blocking probability and the dropping probability of handoff signals, and the blocking probability of new originating call signals.The operator of the system usually gives a service priority to handoff signals compare to new originating call signals. In this paper, the priority is given through channels reservation. A…

In this research the development of identification and classification technique of three wave components of EEG signal, named alpha, beta and theta, is considered. The technique is combination of wavelet transform and power spectral analysis. Wavelet transform was used to extract the wave components so it reduces the data without loss of the information. The wavelet transform also reduces the aspects of non-stationary of the EEG signal. The EEG