Fine structures in the vertical gradient of the electron density have been retrieved by means of analysis of the amplitude of radio occultation (RO) data in sporadic E-layers (heights interval 85-110 km). Maximum values of the positive gradients 45⋅10, 48⋅10, 25⋅10, 29⋅10 [mkm] are located at levels 92, 105 km (GPS/MET event 0393) and 93.5, 100 km (GPS/MET event 0583). Variations in the vertica...

This paper presents a radiopropagation algorithm based on Ray Tracing (RT) technique that combines modified multipath model for constant refractivity gradient profiles and the Uniform Theory of Diffraction (UTD). A novel formulation is proposed by authors calculation ground-reflection analysis ray paths depending atmospheric refractivity. The introduced herein was evaluated in mixed scenario tw...

a series of angiotensin ii (a ii) receptor antagonist of some substituted 5-(biphenyl-4-ylmethyl) pyrazole were subjected to qsar analysis using hansch and fujita-ban model, by using combination of thermodynamic, electronic, spatial descriptor and presence or absence of substituent respectively. several qsar model were obtained using stepwise regression analysis. two models from both the method...

In order to attain glasses with ultra dispersions properties, different heavy metal oxides were used. The desired glasses were obtained from the addition of high amounts of PbO and Bi2O3 to B2O3 based glasses. Refractive index measurements were carried out accurately at different wavelengths by the minimum angle of deviation in prisms method employing a spectrometer. Results indicated that, as ...

Spatially localized refractivity variations, mainly due to water vapor, are a major source of error in high-precision positioning techniques such as GPS and SAR interferometry. Refractivity induced delay variations can be misinterpreted as, e.g., crustal deformation signals or positioning biases. In this study, signal delay estimates based on SAR observations and simultaneous GPS time series ar...

      A series of angiotensin II (A II) receptor antagonist of some substituted 5-(biphenyl-4-ylmethyl) pyrazole were subjected to QSAR analysis using Hansch and Fujita-Ban model, by using combination of thermodynamic, electronic, spatial descriptor and presence or absence of substituent respectively. Several QSAR model were obtained using stepwise regression analysis. Two models from both the ...

stronomical observations near the horizon have historically been made for naval navigation and for determining the time of sunset. Recent applications include near-horizon daytime scene simulation to support infrared search and track and infrared seeker studies. The ray path of the setting or rising Sun can be highly distorted near the horizon, and it is seldom rectilinear. An accurate model of...

Because they are most sensitive to atmospheric moisture content, radar refractivity observations can provide high-resolution information about the highly variable low-level moisture field. In this study, simulated radar refractivity-related phase-change data were created using a radar simulator from realistic highresolution model simulation data for a dryline case. These data were analyzed usin...