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Performance Comparison of GA,PSO,and DE Approaches in Estimating Low Atmospheric refractivity Profiles

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Wuhan University Journal of Natural Sciences 2010年第5期15卷 433-439页

作者： WANG Bo WU Zhensen ZHAO Zhenwei School of Science Xidian University Xi'an 710071 Shaanxi China China Research Institute of Radiowave Propagation Qingdao 266107 Shandong China

Particles swarm optimization（PSO） and differential evolution（DE） algorithms based on optimization are employed to estimate low atmospheric refractivity profiles from radar sea *** atmospheric refractivity profiles are modeled as evaporation *** objective functions,which are used to evaluate the fit of simulated and measured power in estimation procedures,are also investigated at different frequencies such as L-,S-,C-and X-frequency at 10 m/s wind *** results show that all the objective functions are multi-peak *** Adjusted Barton Model of radar cross section（RCS） is *** and DE algorithms are compared with genetic algorithm（GA） by 200 Monte Carlo simulation *** results indicate that DE has the best global search ability,and PSO has the highest success *** to the statistical results,PSO algorithm with the population size 30 is the appropriate way for evaporation duct estimation.

关键词： optimization radar refractivity evaporation duct

Design of a Microcontroller-Based Data Acquisition System for Ground Weather Observations: Evaluation of Radio refractivity of Air

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International Journal of Communications, Network and System Sciences 2014年第9期7卷 355-364页

作者： Amar Adane Ania Ali Yahia Essaid Mameri Abd-El-Hamid Adane Laboratory of Image Processing and Radiation U.S.T.H.B. Algiers Algeria

A meteorological data acquisition system is built using a PIC16F877A microcontroller and electric output-based sensors. This system is programmed in C language using the PCWH compiler. It is smart, accurate, cheap, small, light and easily movable. It is designed to automatically get instantaneous measurements of air temperature, atmospheric pressure, and relative humidity. Depending on their utilisation, these measurements are collected with repetition rate tuneable from one minute to one hour. They are displayed on LCD screen and transferred to a personal computer where they are stored and processed. As an application, such data are recorded in situ and used to estimate the radio refractivity of air near the ground in real time. This parameter is necessary to account for the propagation of radiofrequency waves through the lower atmosphere, during wireless transmissions.

关键词： Microcontroller Sensors C Programming Meteorology Radio refractivity

Modification in Atmospheric refractivity and GPS Based TEC as Earthquake Precursors

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Positioning 2014年第2期5卷 46-52页

作者： Sheetal P. Karia Kamlesh N. Pathak Kunvar S. Yadav Nikita P. Chaudhary Nilesh C. Patel. Ranjan Jana Applied Physics Department S. V. National Institute of Technology Surat India

The present paper reports the modification in GPS TEC (total electron content) and atmospheric refractivity prior to the Iran earthquake that had occurred on 16 April 2013 in Iran (28.10°N, 62.05°E). The analysis of GPS-based TEC from two GPS receivers, Surat (21.16°N, 72.78°E) and Lucknow (26.91°N, 80.95°E ) and results of atmospheric refractivity profile for radiosonde observation stations (Shiraz, Iran and Delhi, India) around the fault line are presented in this paper. It is seen that atmospheric refractivity gets modified from 8 to 6 days prior to the earthquake at Shiraz, Iran and Delhi, India. The GPS TEC showed variations a few days prior to the earthquake. We conclude that in search of precursory signatures for an earthquake, both GPS TEC and refractivity are important parameters.

关键词： Total Electron Content refractivity Earthquake

Seasonal Effect on Atmospheric refractivity in Diverse Terrains

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Journal of Environmental Science and Engineering 2011年第11期5卷 1537-1541页

作者： Y.O. Olasoji M.O. Kolawole Department of Electrical ＆ Electronics Engineering Federal University of Technology Akure Nigeria

Air masses in the atmosphere have contrasting temperature, humidity and moisture, which influence radio signals traversing the atmosphere. The influence of the atmosphere on refractivity is strongly determined by its temporal and spatial variability. This paper uses meteorological measurements to investigate the impact of meteorological structures on diverse environments evident in Nigeria. The study hypothesises that refractivity measures could serve as indicators of diurnal radio wave degradation traversing the atmosphere.

关键词： Radiosonde refractivity radio signal hydrostatic component Longley-Rice model

HEIGHT OF ATMOSPHERIC BOUNDARY LAYER AS DETECTED BY COSMIC GPS RADIO OCCULTATION DATA

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Journal of Tropical Meteorology 2016年第1期22卷 74-82页

作者：刘艳唐南军杨学胜 National Meteorological Center China Meteorological Administration Numerical Weather Prediction Center China Meteorological Administration College of Atmospheric Science Nanjing University of Information Science and Technology

The characteristics of the atmospheric boundary layer height over the global ocean were studied based on the Constellation Observation System of Meteorology,Ionosphere and Climate(COSMIC) refractivity data from 2007 *** show that the height is much characteristic of seasonal,inter-annual and regional ***,the spatial distribution of the annual mean top height shows a symmetrical zonal structure,which is more zonal in the Southern Hemisphere than in the Northern *** boundary layer top is highest in the tropics and gradually decreases towards higher *** height is in a range of 3 to 3.5 km in the tropics,2 to 2.5 km in the subtropical regions,and 1 to 1.5 km or even lower in middle and high *** diurnal variation of the top height is not obvious,with the height varying from tens to hundreds of ***,it is different from region to region,some regions have the maximum height during 9:00 to 12:00,others at 15:00 to18:00.

关键词： statistical characteristics atmospheric boundary layer height refractivity COSMIC/GPS

Anomalous Variation in GPS Based TEC Prior to the 5 Earthquakes in 2009 and 2010

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Positioning 2015年第4期6卷 96-106页

作者： Kunvar S. Yadav Sheetal P. Karia Kamlesh N. Pathak Department of Applied Physics S. V. National Institute of Technology Surat India

The present paper reports the analysis of GPS based TEC measurement corresponding to 5 earthquakes (M > 6.0) that have occurred in 2009 and 2010 during low solar activity period and quiet geomagnetic conditions. The No. of satellites registering high TEC at low elevation angles is observed prior to these earthquakes. The earthquakes are 1) Loyalty Island (22o36'S, 170o54'E) M-6.6 on 19 January 2009, 2) Izu Island (32o48'N, 140o36'E) M-6.6 on 12 August 2009, 3) Ryukyu Islands (23o30'N, 123o30'E) M-6.7 on 17 August 2009, 4) Haiti (18o24'N, 72o30'W) M-7.0 on 12 Jan 2010, 5) Chile (34o12'S, 71o48'W) M-6.9 on 11 March 2010. To identify anomalous behavior of TEC, we compute interquartile range associated with median TEC so as to get upper and lower bound of TEC variation. The results show occurrence of anomalies in VTEC 1 - 13 days prior to the earthquake. The VTEC shows enhancement for all the earthquakes. Enhancement in No. of satellites registering high TEC at low elevation has been observed prior to earthquakes.

关键词： Total Electron Content refractivity Earthquake