Results 241 to 250 of about 4,721 (271)

Evaporation Duct Refractivity Profile

2006 IEEE Antennas and Propagation Society International Symposium, 2006
This paper discusses the principles of evaporation duct refractivity profile estimation using bulk meteorological measurements. Four prevailing models among a number of developed ones were examined. Simulation results were compared with direct refractometric measurements.
Iu. Levadnyi, V. Ivanov
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Uncertainty quantification of propagation in evaporation ducting

2016 URSI International Symposium on Electromagnetic Theory (EMTS), 2016
The Fourier split-step method is used for solving parabolic equations in, for example, computational electromagnetics. In this paper we develop a spectral based Fourier split-step method that will take a limited degree of information with regard to the refractive index of the atmosphere into account.
M. Enstedt, N. Wellander
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Evaporative Cooling in Forced Duct Flow

Transactions of the Canadian Society for Mechanical Engineering, 1975
The cooling of inside surfaces of heated ducts by the process of forced convection with evaporation is studied. Cooling is achieved by liquid-evaporation from the duct surface into a turbulent gas flow. An analysis is developed for predicting the stream and surface temperatures. Data are presented for air-water mixtures.
M.A. Kellow, J.H. VanSant, M. Tarabulsy
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Statistical assessment of evaporation duct propagation

IEEE Transactions on Antennas and Propagation, 1990
Over-the-horizon propagation from 0.6 to 18 GHz is presented in the form of accumulated frequency distributions of path loss, showing the comparisons between theory and two measurement programs. The path-loss theory is based on waveguide solutions for a family of refractivity/height profiles characterized by evaporation duct height in the range of 1 to
H. Hitney, R. Vieth
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Assessment of evaporation duct propagation simulation

2011 XXXth URSI General Assembly and Scientific Symposium, 2011
The evaporation duct strongly influence microwave radars and communication systems. For evaluation of their performance in such environment combination of split-step parabolic equation and Monin-Obukhov similarity theory are usual approach. There are several variants of semiempirical functions used in the similarity theory which leads to different ...
Iurii Levadnyi, Victor Ivanov, Vyacheslav Shalyapin   +2 more
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A modern global evaporation duct climatology

2008 International Conference on Radar, 2008
Climatologies of evaporation duct conditions over the worldpsilas ocean areas are important for radar system design studies and operational planning. The evaporation duct climatology currently in use by the U.S. Navy was developed in the mid-1980s.
Paul A. Frederickson, J. Thomas Murphree, Katherine L. Twigg, Amalia Barrios   +3 more
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Evaporation Duct Refractivity Profile Models

2006 European Microwave Conference, 2006
Four most prevailing models for evaporation duct refractivity profile calculation based on the Monin-Obukhov similarity theory have been examined. The results of computations have been compared with the experimental data obtained by us during two marine expeditions.
Iu. Levadnyi, V. Ivanov, V. Shalyapin
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Study on NPS Evaporation Duct Model

2010 6th International Conference on Wireless Communications Networking and Mobile Computing (WiCOM), 2010
Over the ocean, there is mutual effect between air and sea. This effect would affect atmospheric refractivity, or modified atmospheric refractivity, and a lot of kinds of the profiles of atmospheric refractivity and modified atmospheric refractivity will happen.
Ning Zhang, Nan Li, Bin Tian, Hao Cha, Mo Zhou   +4 more
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Evaluation of the transient electromagnetic field in evaporation duct

Applied Mathematics and Computation, 2004
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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A Ray-Optics Approach for Evaporation Duct Channel Modeling

2018 10th International Conference on Wireless Communications and Signal Processing (WCSP), 2018
In this paper, a three-stage ray optics (RO)-based modeling approach is proposed to characterize the maritime evaporation duct channel. The channel model follows the classic form which is a superposition of multipath components (MPC), while each MPC corresponds to an arrived ray identified by the RO method.
Haifeng Zhou, Jue Wang 0006, Qiang Sun 0001, Wei Feng 0001, Li You 0001, Chen Xu 0005   +5 more
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