The atmosphere of the Earth is opaque to most wavelengths of light in the infrared, in the ultraviolet and in the X-rays. Due to this fact observation of celestial objects in X-rays (in the range of energies from 0.5 to 20 keV) must be carried out outside the atmosphere at altitudes greater than 100 kilometers, namely from space. The development of X-ray astronomy had therefore to await the dev...

In this paper, we address the issue of preserving user privacy in Location Based Services provisioning. This issue includes two controversial requirements, namely the protection of user’s location privacy, and the Location Based Services QoS. In this context, we propose a framework that implements a nonirreversible algorithm, meaning that we cannot discover user’s exact position based on provid...

This work gives a detailed analysis of the relative performance of the recently installed Earth Simulator and the next top four systems in the Top500 list using predictive performance models. The Earth Simulator uses vector processing nodes interconnected using a single-stage, cross-bar network, whereas the next top four systems are built using commodity based superscalar microprocessors and in...

This paper describes technologies from Daden Limited for geographically mapping and accessing live news stories/feeds, as well as other real-time, real-world data feeds (e.g., Google Earth KML feeds and GeoRSS feeds) in the 3-D virtual world of Second Life, by plotting and updating the corresponding Earth location points on a globe or some other suitable form (in-world), and further linking tho...

The Engineering Test Satellite VIII (ETSVIII), scheduled for launch in 2004, has been developed to expand the advanced fundamental technologies required in future space exploitation, including mobile communications technology and high-precision satellite positioning technology [1]. This will be the first Japanese satellite to be equipped with an onboard atomic clock (the High Accuracy Clock: HA...

Over the past few years, astronomers have detected thousands of planets and candidate planets by observing their periodic transits in front of their host stars. A related method, called transit spectroscopy, might soon allow studies of the chemical imprints of life in extrasolar planetary atmospheres. Here, we address the reciprocal question, namely, from where is Earth detectable by extrasolar...

this research intends to develop a method based on the artificial neural network (ann) to predict permanent earthquake-induced deformation of the earth dams and embankments. for this purpose, data sets of observations from 152 published case histories on the performance of the earth dams and embankments, during the past earthquakes, was used. in order to predict earthquake-induced deformation o...

This report starts by describing the continuum model used by Lingle & Clark (1985) to approximate the deformation of the earth under changing ice sheet and ocean loads. That source considers a single ice stream, but we apply their underlying model to continent-scale ice sheet simulation. Their model combines Farrell’s (1972) elastic spherical earth with a viscous half-space overlain by an elast...

In this paper an attempt has been made to compute cross-polarization of millimeter waves in the 30-35 GHz frequency range due to rain. Laws and Parson’s drop size distributions for oblate spheroid drops at 20°C ITU-R (2002) model has been used to predict cross-polarization discrimination (XPD) for circular polarization. The study includes a number of earth stations in India, namely, Ahmedabad, ...