for obtaining reservoir petrophysical properties, for example porosity, non-destructive methods such as x-ray computed tomography, ct, seems to be precise and accurate. porosity is deducted from the ct image with a single scan via different techniques, such as pore space detection by image segmentation techniques then correlation with porosity. more than one hundred samples with carbonate li...

introduction: the photoelectric attenuation coefficient of substances is known to depend upon the energy e of the photon and the effective atomic number of substances (zeff) as (zeff x /e y ).  no definitive values about these indices x, y are given in the literature. the index x is said to lie between, 3.0 and 4.0, while for ‘y’ different values have been assigned, between 3.0 and 4.0. methodo...

Introduction: Radiotherapy involves all methods that can provide a special amount of ionizing radiation to malignant tissue with the assumption that minimal damage to healthy tissues is achieved. We are looking for a valuable and reliable method to measure the absorption dose and also the ability to measure the absorption dose distribution in three dimensions, which today is th...

The number of species of macro organisms on the planet is estimated at about 10 million. This staggering diversity and the need to better understand it led inevitably to the development of classification schemes called biological taxonomies. Unfortunately, in addition to this enormous diversity, the traditional identification and classification workflows are both slow and error-prone; classific...

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A new algorithm for evaluating the atomic size is suggested by entailing the atomic spectroscopic data-the wave number. The basic tenet of the present method is (i) to convert a multi-electron atom system to a hydrogenic atom to invoke the Bohr model for the mechanism of electron transition, and (ii) to use the experimental atomic spectroscopic data of multi electron systems to determine the at...

The purpose of this work is to present a new method to extract the electron density ([Formula: see text]) and the effective atomic number (Z eff) from dual-energy CT images, based on a Karhunen-Loeve expansion (KLE) of the atomic cross section per electron. This method was used to calibrate a Siemens Definition CT using the CIRS phantom. The predicted electron density and effective atomic numbe...

An approach is presented to automatically segment and label a continuous observation sequence of hand gestures for a complete unsupervised model acquisition. The method is based on the assumption that gestures can be viewed as repetitive sequences of atomic components, similar to phonemes in speech, starting and ending in a rest position and governed by a high level structure controlling the te...

We describe the derivation and testing of a knowledge-based atomic environment potential for the modeling of protein structural energetics. An analysis of the probabilities of atomic interactions in a dataset of high-resolution protein structures shows that the probabilities of non-bonded inter-atomic contacts are not statistically independent events, and that the multi-body contact frequencies...