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1

Passive Radar using Multiple GSM Transmitting Stations  

Microsoft Academic Search

The atmosphere has a wide range of transmissions available from various sources like TV transmissions, GSM signals, FM Radio, AM Radio, GPS signals, etc. These signals open up the opportunity of designing different types of passive radars. Passive radar using a single GSM transmitting station have been designed, but this type of radar cannot give accurate target parameters. This paper

U. M. D. Mendi; B. K. Sarkar

2006-01-01

2

Satellite observations with a single radar tracking station  

NASA Astrophysics Data System (ADS)

Handicaps in observations due to the relative motion between a satellite and the radar station are highlighted. It is shown that decaying high-risk space objects can be observed by a single radar tracking station. But less than 10% of an orbit and 50% of all orbits per day are within line-of-sight of the radar station. Breaks of 14 hr between 2 consecutive passages are possible. This can cause total target loss because of outdated orbit data. Cooperation with observation stations in other parts of the world is therefore desirable. In order to fit the observation requirements the radar should deliver angular direction, range, and at least echo amplitude measurements.

Mehrholz, D.

3

Evaluation of performance of Micro Rain Radar over the tropical coastal station Thumba (8.5°N, 76.9°E)  

NASA Astrophysics Data System (ADS)

The vertically pointing Micro Rain Radar (MRR) and disdrometer (RD-80) were installed at a coastal station, Thumba (8.5°N, 76.9°E), to study the characteristics of tropical rains. This paper presents the first results from these observations over Thumba and highlights the impact of Mie-scattering corrections to the MRR data for proper estimation of the rainfall intensity. To evaluate the performance of MRR, a total number of 11 Mesoscale Convective Systems events were considered during the period September 2006 to December 2007. The uncorrected MRR shows an overestimation of rain rate and this is larger during the high rain rates. The Mie scattering corrections lead to a decrease in rain rate of the order 2%-31% and resulted in substantial improvement in the rainfall accumulation (368.69 mm (before) to 302.16 mm (after)). The accumulated rainfall is in good agreement with disdrometer total rainfall of 299.14 mm. For the first time, the impact of Mie scattering for different rain categories has been investigated and study shows the rainfall sum significantly improved (about 22%) during the moderate and heavy rain categories whereas, it shows improvement of 11% during the light rain. These studies may be used to estimate the rain attenuation at Ka band over Indian region for different rain categories.

Kirankumar, N. V. P.; Kunhikrishnan, P. K.

2013-12-01

4

Four Station Interferometric Radar Observations of Mars  

Microsoft Academic Search

Planetary targets have been observed with radar since the late 1950s when it was first used for ranging experiments with the Moon. As telescope size and power increased, it became possible to observe more distant targets (Venus, Mars, and the outer satellites). Inherent to radar observations is the uncertainty as to the source of the reflection, there being two points

K. W. Larsen; R. F. Jurgens; R. E. Arvidson; M. A. Slade; A. F. Haldemann

2002-01-01

5

Shuttle rendezvous radar performance: evaluation and simulation  

Microsoft Academic Search

The authors describe the performance evaluation and simulation of the Ku-band shuttle rendezvous radar. Computer simulation, using the radar cross section for specific spacecraft, provided an estimate of rendezvous radar range performance for that spacecraft. The radar cross section model included smooth metallic surfaces, rough surfaces, and shadowing effects, as well as phase differences due to different path lengths to

J. W. Griffin; A. C. Lindberg; T. B. Ahn; P. L. Harton

1989-01-01

6

Topography adjacent to Signal Corps Radar (S.C.R.) 296 Station 5, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Topography adjacent to Signal Corps Radar (S.C.R.) 296 Station 5, showing conditions before construction, May 28, 1943, this drawing shows the Bonita Ridge access road retaining wall and general conditions at Bonita Ridge before the construction of Signal Corps Radar (S.C.R.) 296 Station 5 - Fort Barry, Signal Corps Radar 296, Station 5, Transmitter Building Foundation, Point Bonita, Marin Headlands, Sausalito, Marin County, CA

7

New-type echoes observed with the 50 MHz auroral Doppler radar at Showa Station  

Microsoft Academic Search

VHF Doppler radars have been used for the study of auroral E-region irregularities. The Doppler spectra of radar echoes, which give important information for investigating the plasma instabilities responsible for irregularities, are categorized into type 1 - 4. This report presents a new type of aurora echoes detected by the 50 MHz auroral Doppler radar at Showa Station. Preliminary statistical

Manabu Kunitake; Takashi Tanaka; Kiyoshi Igarashi; Shinichi Yamamoto; Hideo Maeno; Tadahiko Ogawa

1993-01-01

8

Design of square-loop frequency selective surfaces utilize C-band radar stations  

Microsoft Academic Search

This research proposes to utilize square-loop frequency selective surface (FSS) in a radar station to increase the efficiency of communication systems and in the same time protect the staff and people against biological effects of C-band microwave radiation. In a radar station, waves propagate in undetermined directions and different frequency ranges which can effect on health of staff and people

M. Hosseinipanah; Qun Wu; Chengwen Zhang; F. A. Mianji; Guohui Yang

2008-01-01

9

Remote maintenance and monitoring incorporated into primary and secondary radar stations  

NASA Astrophysics Data System (ADS)

The objective of remote maintenance and monitoring (RMM) is to determine radar station operation status via analysis of main equipment parameters and to enable automatic reconfiguration in case of equipment failure. The RMM concept and philosophy are described as well as the structure of a radar station with RMM. Consideration is also given to B.I.T.E. equipment functions, central computer functions, and information presentation.

Turlais, P.

10

Synthetic Aperture Helicopter Radar Experimental Evaluation Program.  

National Technical Information Service (NTIS)

The purpose of the program is to determine the resolution and MTI performance of a helicopter radar concept employing rotor tip mounted antennas and real-time digital synthetic aperture processing. The approach involves an experimental evaluation of the c...

N. F. Powell

1969-01-01

11

Synthetic Aperture Helicopter Radar Experimental Evaluation Program.  

National Technical Information Service (NTIS)

The document is the first Quarterly Report for the Synthetic Aperture Helicopter Radar Experimental Evaluation program; it covers work performed between 1 February and 30 April 1969. In scope the program is to determine the resolution and MTI performance ...

N. F. Powell

1969-01-01

12

Passive Radar Imaging Algorithm Based on Subapertures Synthesis of Multiple Television Stations  

Microsoft Academic Search

In this paper, we presents a passive radar imaging algorithm based on signals received from multiple television stations at various aspect angles and bistatic equivalence theorem. The algorithm reconstructs a target image by synthesizing the subapertures of multiple television stations available into a large equivalent aperture. In addition to the high efficiency in imaging and low complexity in computation, the

Wang Jun; Zhang Xinwen; Bao Zheng

2006-01-01

13

Images of Venus by Three-Station Radar Interferometry—1977 Results  

Microsoft Academic Search

During the 1977 inferior conjunction of Venus, radar observations were made using three receiving stations as a multiple interferometer. Maps of surface reflectivity and altimetry were prepared from these observations. The new altimetry maps show considerable improvement in relation to many of the earlier maps made using the two-station interferometer. In particular, there are consistent and explainable correlations between the

R. F. Jurgens; R. M. Goldstein; H. R. Rumsey; R. R. Green

1980-01-01

14

Evaluation of the new French operational weather radar product for the field of urban hydrology  

NASA Astrophysics Data System (ADS)

The main objective of this paper is to evaluate, at the urban scale, the accuracy of the new French operational radar processing chain deployed within the French operational weather radar network. Such an evaluation is conducted by comparing radar data resulting from this processing chain (with a 1-km 2 resolution) to rain gauge data at four different time scales, i.e. 5, 15, 30 and 60 min. These data are supplied by the Trappes Radar Station, located 30 km southwest of Paris. A total of 69 rain gauges installed within a radius of 80 km from the weather radar have provided the ground reference data. The dataset comprises 50 varied rainy days. The influence of distance, quality code of the radar data and type of rainfall, as well as the adjustment factor, is analyzed. The present analysis moreover seeks to evaluate the error specific to reference data by considering instrumental and representativeness errors, for the purpose of taking reference data accuracy into account in the radar/rain gauge comparison. This study shows that radar data obtained by means of this new operational radar processing chain are not yet reliable enough for direct use in quantitative applications within the field of urban hydrology.

Emmanuel, I.; Andrieu, H.; Tabary, P.

2012-01-01

15

Human factor as an important phenomenon for the optical radar station operation  

NASA Astrophysics Data System (ADS)

Satellite laser ranging station close Helwan, a suburb of Egyptian capital city Cairo, is the cooperative lab of the astronomical department of National Research Institute of Astronomy and Geophysics, Egypt and the department of physical electronics of Czech Technical University, Faculty of Nuclear Sciences and Physical Engineering, Czech Republic. The aim of the station is the accurate and precise measurement of distance between station reference point and some artificial satellites. The measurement is based on an optical radar principle. The station location is determined by both attractive location from point of view geosciences and acceptable local climatic conditions. We are reporting about the involving local staff in the daily operation of the station and about influence of the training, motivation and local staff qualification improvement on measurement results.

Novotny, Antonin; Blazej, Josef

2007-05-01

16

Terminal Doppler weather radar operational test and evaluation, Orlando 1990  

Microsoft Academic Search

Lincoln Laboratory conducted an evaluation of the Federal Aviation Administration (FAA) Terminal Doppler Weather Radar (TDWR) system in Orlando, Florida during the summer of 1990. In previous years, evaluations have been conducted at airports in Kansas City, MO (1989) and Denver, CO (1988). Since the testing at the Kansas City International Airport, the radar was modified to operate in C-band,

David M. Bernella

1991-01-01

17

PAVE PAWS Early Warning Radar Operation Cape Cod Air Force Station, MA. Record of Decision.  

National Technical Information Service (NTIS)

This document records the decisions of the United States Air Force with regard to the Supplemental Environmental Impact Statement (SEIS) for the continued operation of the Pave PAWS radar at Cape Cod AFS (December 2008) that was prepared to evaluate poten...

2009-01-01

18

Principals of Radar and Meteorological Radar Devices.  

National Technical Information Service (NTIS)

Three meteorological radar units are described: the Malachite radiotheodolite with rangefinder attachment, the Meteorite radar station, and the MRL radar station. The principles of operation of these systems are given along with circuit descriptions and e...

O. G. Korol R. D. Chernyak

1973-01-01

19

Airborne Radar Sounding Studies of a Subglacial "Lake" Near South Pole Station, Antarctica  

NASA Astrophysics Data System (ADS)

Radar ice sounding transects have revealed what appears to be a subglacial lake beneath 2800 meters of ice 10.5 kilometers from the South Pole. It has been proposed that sterile drilling be tested at this lake, a location accessible from the existing South Pole Station. Not only would this allow for techniques to be tested before risking contamination of Lake Vostok, but there is also the possibility of finding exotic microorganisms in a permafrost-like bed. Other workers have concluded that the lake is frozen by analyzing temperature measurements in the South Pole ice and extrapolating a base temperature at the "lake" using several different models. Here, we attempt to determine the material of the lake by extracting its properties through a complete solution to the radar equation. The radar equation accounts for all the factors that influence the returned echo strength, including radar system parameters and propagation effects. The largest unknown quantity is the ice loss, which depends on the temperature and impurities throughout the ice. For this analysis, we use temperature profiles corresponding to both a frozen and a liquid base and several possible dielectric loss models to compute ice loss. The strength of the returned echo is also affected by the material making up the "lake" and its roughness. The reflection coefficients calculated for a temperature profile allowing melt are not consistent with a glacier/liquid-water interface, thus implying that this "lake" is indeed frozen. Further analysis of the reflection coefficients indicates that they correspond to impure ice, and local topography suggests that this feature is possibly an ancient lake.

Lindzey, L. E.; Blankenship, D. D.; Peters, M. E.

2003-12-01

20

Ground-penetrating radar evaluation of bridge decks  

NASA Astrophysics Data System (ADS)

Radar has emerged as a valuable non-destructive test method for evaluating the condition of New Hampshire bridge decks. It allows the inspector to 'see' the top surface of the portland cement concrete deck which is typically covered with asphalt pavement. Radar is also very 'customer friendly' in that it allows inspectors to evaluate the bridge decks without closing travel lanes or otherwise impeding traffic flow in any way. This paper discusses the inspection needs of the New Hampshire Department of Transportation which necessitated the use of radar, as well as a history of its selection, development, and incorporation into New Hampshire's bridge management system.

Roberts, Glenn E.

1995-05-01

21

MST radar and radiosonde observations of inertia-gravity wave climatology over tropical stations: Source mechanisms  

NASA Astrophysics Data System (ADS)

In this paper, possible source mechanisms for the generation of inertia-gravity wave activity over a tropical station, Gadanki (13.5°N, 79.2°E), are investigated using a long-term data set obtained from Indian mesosphere-stratosphere-troposphere (MST) radar. The gravity wave analysis is carried out in two different height regions, namely, 4-14 and 17-21 km, representing the troposphere and lower stratosphere, respectively. Clear seasonal variation in the wave activity has been noticed in both regions with maximum (minimum) in winter (monsoon) in the troposphere. But it is maximum (minimum) in monsoon (winter) in the lower stratosphere. This kind of winter enhancement in the wave activity is not expected at this tropical site. Interestingly, the contribution of the meridional component to the total kinetic energy (Ek) is found to be dominant rather than zonal in the winter except during 1997-1998. Topography seems to be the likely source for the generation of wave activity during winter in the troposphere. The influence of this topography is also reflected in the nearby radiosonde stations, Chennai (13.0°N, 80.2°E) and Bangalore (12.9°N, 77.6°E), which are located at radial distances of 128 and 190 km from Gadanki, respectively. Although two major sources, that is, strong convection and wind shears, coexist during monsoon season, strong wind shear seems to be the likely source of the wave activity. Large interannual variability in the wave activity is also noticed from 9 years (September 1995 to December 2004) of data. Good consistency is observed between the wave activities observed from nearby (Chennai) radiosonde and Gadanki MST radar data sets. Making use of a network of radiosonde observations operated by India Meteorological Department, we also present the latitudinal variation of wave activity. From the latitudinal variations it is observed that large-scale systems can also influence the generation of the gravity wave activity over larger areas.

Venkat Ratnam, M.; Narendra Babu, A.; Jagannadha Rao, V. V. M.; Vijaya Bhaskar Rao, S.; Narayana Rao, D.

2008-04-01

22

Synthetic Aperture Helicopter Radar Experimental Evaluation Program.  

National Technical Information Service (NTIS)

The object of the program is to determine the resolution and MTI performance of a helicopter radar concept employing rotor tip mounted antennas and real-time digital synthetic aperture processing. The present report describes and analyzes the results of s...

N. F. Powell

1969-01-01

23

Assimilating spaceborne radar and ground-based weather station data for operational snow-covered area estimation  

Microsoft Academic Search

An enhanced method for snow-covered area (SCA) estimation for boreal forest zone is presented. The method combines TKK developed spaceborne radar-based SCA estimation with ground-based weather station observations. The purpose is to improve the reliability of SCA estimates near and after the end of snow-melt season. The SCA estimates acquired with the enhanced method are compared with optical satellite data-based

K. Luojus; J. Pulliainen; S. Metsamaki; S. Anttila; M. Hallikainen

2007-01-01

24

Theoretical Fundamentals of Radar.  

National Technical Information Service (NTIS)

The book examines the principles of radar, methods of coordinate measurement and scanning and circuits for radar stations of three types: with an operator, a continuous computer installation and a digital computer. It presents the characteristics of radar...

A. A. Korostelev A. V. Petrov N. I. Burenin V. E. Dulevich Y. A. Melnik

1967-01-01

25

Simultaneous PMC and PMSE observations with a ground-basedlidar and SuperDARN HF radar over Syowa Station, Antarctica  

NASA Astrophysics Data System (ADS)

A Rayleigh-Raman lidar system had been installed by the 52nd JapaneseAntarctic Research Expedition on February, 2011 at Syowa Station Antarctica(69.0°S, 39.5°E). Polar Mesospheric Cloud (PMC) was detected by the lidar at22:30UT (+3hr for LT) on Feb 4th, 2011, the first day of a routineoperation. This event is the first time to detect PMC over Syowa Station bya lidar. In the same night, SuperDARN HF radar with oblique incidence beamsalso detected Polar Mesosphere Summer Echoes (PMSEs) during 21:30UT to23:00UT. Although these signals were detected at different times andlocations, PMC motion estimated using horizontal wind velocities obtained bya collocated MF radar strongly suggests that they have a common origin (i.e.ice particle). We consider that this event occurred in the end of PMCactivity period at Syowa Station in the austral summer season (2010-2011),since the lidar did not detected any PMC signals on other days in February,2011. This is consistent with satellite-born PMC observations by AIM/CIPSand atmospheric temperature observations by AURA/MLS instruments.

Suzuki, Hidehiko; Nakamura, Takuji; Tsutsumi, Masaki; Kawahara, Takuya D.; Ogawa, Tadahiko; Tomikawa, Yoshihiro; Ejiri, Mitsumu K.; Sessai Yukimatu, Akira; Abo, Makoto

2012-07-01

26

Application of 50 Mhz Doppler Radar Wind Profiler to Launch Operations at Kennedy Space Center and Cape Canaveral Air Station.  

National Technical Information Service (NTIS)

This paper presents a case study where a significant wind shift, not detected by jimspheres, was detected by the 50 MHz DRWP (Doppler Radar Wind Profiler) and evaluated to be acceptable prior to the launch of a Shuttle. This case study illustrates the imp...

R. S. Schumann G. E. Taylor S. A. Smith T. L. Wilfong

1994-01-01

27

Night-side DP-2 type fluctuations observed by the FM-CW Radar and MAGDAS stations  

NASA Astrophysics Data System (ADS)

DP-2 type fluctuations caused by IMF southward/northward variations have important information about how the solar wind effects are transferred into the magnetosphere, ionosphere, and on the ground. Since dayside ground magnetic field variations are significantly enhanced during DP-2 events, dayside DP-2 fluctuations have been investigated for many years. However night-side DP-2 variations are not yet investigated sufficiently. In this study, we examined night-side magnetic and electric field variations when DP-2 was observed in dayside. Ground data from MAGDAS/CPMN (MAGnetic Data Acqisition System and Circum-pan Pacific Magnetometer Network) stations were analyzed. We also investigated the association of DP-2 with the ionospheric electric fields obtained by the FM-CW (Frequency Modulated Continuous Wave) radar at PTK (M.Lat. = 45.8 degree, M.Lon.= 221.6 degree) and solar wind parameters from the ACE satellite. The amplitudes of night-side DP-2 on 11 Oct., 2008 became greater with increasing of the latitude of 210 MM stations. While there were no Pi 2 pulsations, and signatures of substorms were not detected with the DP 2. At the time, westward electric field was observed by the FM-CW radar in the night-side sector simultaneously with the positive variation of night-side ground magnetic fields. Therefore the night-side DP-2 magnetic fluctuation is found not to be caused by the ionospheric currents.

Ikeda, A.; Yumoto, K.; Uozumi, T.; Abe, S.; Shinohara, M.; Nozaki, K.; Yoshikawa, A.; Bychkov, V.; Shevtsov, B.; Sugon, Q.; McNamara, D.

2010-12-01

28

Terminal Doppler weather radar operational test and evaluation, Orlando 1990  

NASA Astrophysics Data System (ADS)

Lincoln Laboratory conducted an evaluation of the Federal Aviation Administration (FAA) Terminal Doppler Weather Radar (TDWR) system in Orlando, Florida during the summer of 1990. In previous years, evaluations have been conducted at airports in Kansas City, MO (1989) and Denver, CO (1988). Since the testing at the Kansas City International Airport, the radar was modified to operate in C-band, which is the intended frequency band for the production TDWR systems. The objectives of the 1990 evaluation period were to evaluate TDWR system performance in detecting low-altitude wind shear, specifically microbursts and gust fronts, at the Orlando International Airport and in the surrounding area; to refine the system's wind shear detection capabilities; and to evaluate elements of the system developed by the contractor, which were new for the C-band system and therefore not available for evaluation in previous years. Some performance comparisons are made among results from the vastly different weather environments of Denver, Kansas City, and Orlando. Statistics are presented and discussed for the performance of the system in detecting and predicting microbursts and gust fronts. A significant use of the prediction capability is its potential use for air traffic control (ATC) personnel to plan airport operations when hazardous weather is predicted. Issues such as low velocity ground clutter (from tree leaves, road traffic, and dense urban areas) that affect prediction performance are discussed along with possible software modification to account for them.

Bernella, David M.

1991-04-01

29

Field Evaluation of Truck Weigh Station Operations  

Microsoft Academic Search

Weigh-in-Motion (WIM) systems can improve the capacity of weigh-station operations by screening trucks traveling at high speeds and requiring only trucks within a threshold of a maximum permissible weight or axle load to be weighed on more accurate static scales. The efficiency of a weigh station is highly dependent on the accuracy of the WIM screening system. This article examines

Hesham Rakha; Bryan Katz; Ahmed Al-Kaisy

2006-01-01

30

Radar sounding of Mars from the orbit of the Mars-Express automatic interplanetary station  

NASA Astrophysics Data System (ADS)

On the base of the laser altimetry results obtained using the orbital altimeter MOLA (the MGS mission) and the data of radio occultation experiments of transionospheric sounding of the Mars ionosphere, a method for interpretation of the planet radar sounding data is developed. The proposed method includes a program package for numerical simulation of the process of radiowave propagation through the media under study.

Smirnov, V. M.; Chernaya, L. F.; Yushkova, O. V.; Rykov, K. N.

2006-07-01

31

Human factor as an important phenomenon for the optical radar station operation  

Microsoft Academic Search

Satellite laser ranging station close Helwan, a suburb of Egyptian capital city Cairo, is the cooperative lab of the astronomical department of National Research Institute of Astronomy and Geophysics, Egypt and the department of physical electronics of Czech Technical University, Faculty of Nuclear Sciences and Physical Engineering, Czech Republic. The aim of the station is the accurate and precise measurement

Antonin Novotny; Josef Blazej

2007-01-01

32

Seasonal temperature variation around the mesopause inferred from a VHF meteor radar at King Sejong Station (62S, 59W), Antarctica  

Microsoft Academic Search

A VHF meteor radar, installed at King Sejong Station in March, 2007, has been detecting echoes from more than 20,000 meteors per day. Meteor echoes are decayed typically within seconds as meteors spread away by atmospheric diffusion. The diffusion coefficients can thus be obtained from decay times of meteor echo signals, providing with information on the atmospheric temperatures and pressures

Yongha Kim; Jeong-Han Kim; Changsup Lee; Gun-Hwa Jee

2008-01-01

33

Fabrication of Radar Absorbing Structure and Evaluation of Radar Cross Section: Case Study of Hybrid Shells  

Microsoft Academic Search

Fiber-reinforced composite materials have outstanding mechanical and electrical properties; their applications have been expanded to commercial products as well as military components. Using composite materials, researchers have studied the radar absorbing, or `stealth' technology. In this research, to develop the radar absorbing structure (RAS), hybrid composite materials are fabricated into three-dimensional `C' and `U' shape shells. A series of experiments

Woo-Kyun Jung; Sung-Hoon Ahn; Bierng-Chearl Ahn; Seoung-Bae Park; Myung-Shik Won

2007-01-01

34

Availability & Reliability Evaluation of Dokan Hydro Power Station  

Microsoft Academic Search

This paper introduces a Markov reliability model for Dokan hydro power station by studying the operational data of this station for period 2001-2005. The most important reliability indices are found namely failure rate ? and repair rate mu through data collection and analysis. The availability and reliability of individual units and for the power plant are evaluated by taking into

A. R. Majeed; N. M. Sadiq

2006-01-01

35

Universal Ground Control Station (UGCS) joystick evaluation  

Microsoft Academic Search

A goal of commonality and interoperability across U.S. Army and Joint Service unmanned aerial systems (UASs) was outlined by the Office of the Secretary of Defense. The Universal Ground Control Station (UGCS) is a U.S. Army initiative to meet this requirement. With an objective to control heterogeneous assets with expanded payloads, both displacement and force sensing hand-controllers have been reviewed

Susan R. Flaherty; Lisa Fern; Terry Turpin; Scott Scheff

2012-01-01

36

3. VIEW NORTHWEST, height finder radar towers, and radar tower ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. VIEW NORTHWEST, height finder radar towers, and radar tower (unknown function) - Fort Custer Military Reservation, P-67 Radar Station, .25 mile north of Dickman Road, east of Clark Road, Battle Creek, Calhoun County, MI

37

Simultaneous observations of Vertically Pointing Micro Rain Radar (MRR) and Disdrometer over a tropical station Thumba  

NASA Astrophysics Data System (ADS)

The Micro Rain Radar (MRR) and disdrometer (RD-80 model by Distromet Ltd., Switzer-land) was installed at Thumba (8.50N, 76.90E) under Ka band propagation experiment is used extensively to measure the rain rate along with the Raindrop size distribution (DSD) of trop-ical continental rainfall. In this study, simultaneous observations of Micro Rain Radar and disdrometer data collected for 3 years are analyzed to retrieve DSD parameters using gamma distribution for different precipitating systems. First, using the disdrometer data, the rainfall events were separated into convective, transition and stratiform rainfall by an algorithm based on variation of DSD parameters. At the same time, profiler-derived equivalent reflectivity and Doppler velocity from Doppler spectra were used to classify precipitation. Overall agreement between the two instruments is found to be reasonable. A Comparison of the retrieved gamma parameters with disdrometer measurements shows very good agreement. Correlation coefficient of ?=0.95,0.94 and 0.95 for the rain rate, liquid water content and median volume diameter respectively are observed between profiler and disdrometer for the whole observation period. During stratiform regime vertical variability of gamma parameters shows very little variation where as during transition mixed large and small drop spectra are observed. The significance of the present results demonstrates the capability of Ka band in classifying the precipitating systems and shows the spatial and temporal variability of DSD in transition and stratiform rain type.

Nadimpally, Kirankumar; Pk, Kunhikrishnan

38

Terminal Doppler Weather Radar (TDWR) Build 5 Test and Evaluation Master Plan (TEMP).  

National Technical Information Service (NTIS)

This document presents the Terminal Doppler Weather Radar (TDWR), Build 5 enhancement, Test and Evaluation Master Plan (TEMP). This Build 5 TEMP identifies Operational Test and Evaluation (OTE) objectives, responsibilities, resources, schedules, and criti...

E. Turcich R. Cranston

1994-01-01

39

Performance Evaluation of Automotive Radars Using Carrier-Phase Differential GPS  

Microsoft Academic Search

We describe a centimeter-level ground-truth system based on GPS relative positioning. One of the goals of the system is for performance evaluation of automotive radars by creating objective test procedures for the radars. In support of this goal, an effective scheme is used to handle signal attenuation or blockage that leads to the changes of satellite visible map and cycle

Shuqing Zeng

2010-01-01

40

RCS evaluation of complex objects coated with radar absorbing materials using the complex ray method  

Microsoft Academic Search

The strategy and results of an RCS (radar cross section) evaluation of a dihedral corner reflector coated with lossy materials using the complex ray method are described. A computer program based on the analysis presented has been developed to perform effective RCS calculations of dihedral corner reflectors having the inner surfaces coated with or without radar adsorbing materials. One of

Y. Z. Ruan; H. P. Du

1992-01-01

41

Offshore next generation weather radar (NEXRAD) test and evaluation master plan (TEMP)  

Microsoft Academic Search

This document provides the test philosophy and approach for the Offshore Next Generation Weather Radar (NEXRAD) Test and Evaluation Master Plan (TEMP). The NEXRAD differs from the typical Federal Aviation Administration (FAA) weather radar acquisition in that it is jointly funded by the Department of Defense (DOD), the Department of Commerce (DOC), and the Department of Transportation (DOT). These three

Radame Martinez; Robert Cranston; John Porcello

1995-01-01

42

2. VIEW SOUTHWEST, prime search radar tower, height finder radar ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. VIEW SOUTHWEST, prime search radar tower, height finder radar towards, height finder radar towers, and radar tower (unknown function) - Fort Custer Military Reservation, P-67 Radar Station, .25 mile north of Dickman Road, east of Clark Road, Battle Creek, Calhoun County, MI

43

Spaceborne Radar Study.  

National Technical Information Service (NTIS)

Three air-defense radar surveillance systems are described, each consisting of active radar satellites capable of operating at earth-synchronous orbit altitude with associated ground control stations. Systems 1 (three satellites) provides a detection fenc...

J. Greene R. Kaplan G. J. McNiff P. Nosal J. L. Schultz

1974-01-01

44

Gravity waves and turbulence from troposphere to mesosphere over the Indian MST radar station  

NASA Astrophysics Data System (ADS)

The Indian MST radar facility at Gadanki (13.5° N, 79.2° E) has been utilised to study the backscattered signals received near simultaneously from troposphere, stratosphere and meso-sphere. The main objective is to identify the signatures of gravity waves in the troposphere/stratosphere and their upward propagation to produce mesospheric turbulence. The observations were car-ried out during different months of 2001-2003 using five beam positions for E-W, N-S at 10° beam angle and the Zenith direction, variable pulse widths (range bins between 150 m to 2.4 km) and minimum time resolution of 80 s (for one radar scan) covering the height range of 4-85 km. While results shown on the intermittent, inhomogeneous and anisotropic nature of mesospheric scattering regions are explained by the neutral turbulence driven perturbations in the radio refractive index corresponding to the Bragg scale of about 3 m for the radar frequency of 53 MHz, the seasonal variation in the occurrence of scattering layer heights between 70-80 km (including stratification and multiple layers) and signal strengths are dependent on (but may not be limited to) the severe weather related tropical convective sources generating grav-ity waves in the troposphere, their propagation through the stratosphere and breaking in the mesosphere. The spectrum of gravity waves of a convective event with different phase velocities would go through various interaction regimes with the mean flows acting as filters as well as producing turbulence in all the three regions of interest. On a typical day (e.g. 25 June 2002) of well developed mesospheric scattering layer, the height profile of SNR (related to different turbulence patches) shows an average maximum value of 15 dB below 18 km with 3-4 prominent and continuous tropospheric scatter layers of 3 km thickness and 5 dB in the mesosphere with 2 km thick intermittent layer around 74 km. Wind velocity contours show a reversal in mean wind direction around 8-10 km for zonal and meridional components. The time sequence of horizontal and vertical winds in the scatter-ing layers of troposphere/stratosphere show background mean wind superimposed by random peaks pertaining to perturbations due to mean flow-gravity wave interactions. The growth or decay of these perturbation fields with height depends on their filtering and dissipation states to produce turbulence. The unobstructed gravity waves are able to reach higher altitudes of even mesosphere where they may break down to generate turbulence. Wavelet analyses of (a) wind velocities in selected scattering and non-scattering height regions of troposphere/stratosphere and (b) SNR data of mesosphere provide details of scales and coefficients of available gravity wave spectra at each altitude and their relation to the onset of turbulence at various levels. The 19 November 2001 data subjected to wavelet analysis shows that the gravity waves observed in the tropospheric scattering layers at 15 and 18 km propagate up and produce two scattering layers at 70 and 75 km. Available gravity wave propagation models like that of Lindzen (1981) is used and extended to incorporate the observed interplay of mean wind, gravity wave pertur-bations and turbulence in the lower atmosphere and the prediction of generation of turbulence in the mesosphere.

Chakravarty, Subhas

45

Test and Evaluation of Passive Horn Antenna for the Airport Surveillance Radar-5.  

National Technical Information Service (NTIS)

A passive horn modification kit was developed by the Raytheon Company for the National Aviation Facilities Experimental Center, Airport Surveillance Radar-5 test bed. The modified system was evaluated to determine the extent of performance improvements re...

D. L. Offi

1974-01-01

46

The RADAR Test Methodology: Evaluating a MultiTask Machine Learning System with Humans in the Loop  

Microsoft Academic Search

The RADAR project involves a collection of machine learning research thrusts that are integrated into a cognitive personal assistant. Progress is examined with a test developed to measure the impact of learning when used by a human user. Three conditions (conventional tools, Radar without learning, and Radar with learning) are evaluated in a large-scale, between- subjects study. This paper describes

Aaron Steinfeld; Rachael Bennett; Kyle Cunningham; Matt Lahut; Pablo-Alejandro Quinones; Django Wexler; Dan Siewiorek; Paul Cohen; Julie Fitzgerald; Othar Hansson; Jordan Hayes; Mike Pool; Mark Drummond

47

Airborne Radar Approach Flight Test Evaluating Various Track Orientation Techniques.  

National Technical Information Service (NTIS)

This comprehensive report presents the results of a flight test experiment of an Airborne Radar Approach (ARA) System utilizing various track orientation techniques and operational modes. The tests were performed in the immediate area of NAFEC in Atlantic...

L. D. King

1980-01-01

48

Evaluation of telecommunication station parameters by means EM field measurements  

Microsoft Academic Search

The paper presents a method for the evaluation of telecommunication station parameters by means of electromagnetic field measurements. If exploited with electromagnetic field simulators, it allows a more accurate analysis of the electromagnetic field levels radiated by a plant. Both numerical examples and real-life experiments show that the method is accurate and that it can be usefully applied for electromagnetic

M. Bertocco; D. Dainese; A. Sona

2004-01-01

49

PQLX: A Software Tool to Evaluate Seismic Station Performance  

NASA Astrophysics Data System (ADS)

We present a new tool that will allow users to evaluate seismic station performance and characteristics by providing quick and easy transitions between visualizations of the frequency and time domains. The software is based on the probability density functions (PDF) of power spectral densities (PSD) (McNamara and Buland, 2004). The computed PSDs are stored in a MySQL database, allowing a user to access specific time periods of PSDs (PDF subsets) and time series segments through a GUI-driven interface. The power of the method and software lies in the fact that there is no need to screen the data for system transients, earthquakes or general data artifacts since they map into a background probability level. In fact, examination of artifacts related to station operation and episodic cultural noise allow us to estimate both the overall station quality and a baseline level of earth noise at each site. The output of this analysis tool is useful for both operational and scientific applications. Operationally, it is useful for characterizing the current and past performance of existing broadband stations, for conducting tests on potential new seismic station locations, for detecting problems with the recording system or sensors, and for evaluating the overall quality of data and meta-data. Scientifically, the tool allows for mining of PSDs for investigations on the evolution of seismic noise (see Aster et al., Hutt et al., Leeds et al., and Oneel et al., this meeting). The PDF algorithm and initial software were developed by the USGS as a part of the ANSS/GSN data and network QC system. Further development, supported by the IRIS Data Management Center, integrated the PDF algorithm into the IRIS QUACK system. The newest version, PQLX, combines the PDF system with the PQL time series viewing tool developed with support from IRIS PASSCAL. Currently, PQLX is operational at the USGS ANSS NOC and ASL for station performance monitoring.

McNamara, D. E.; Boaz, R. I.

2006-12-01

50

Technical evaluation of the station and instrument ground grid systems at the Davis Besse Nuclear Power Station, Unit 1  

SciTech Connect

This report documents the technical evaluation of the station and instrument ground grid systems at the Davis Besse Nuclear Power Station, Unit 1. The evaluation is to determine that there are no inadvertent ties between the instrument and station ground grid systems, that any identified inadvertent ties are corrected, and to assure that the installation meets design criteria. The information submitted by the licensee indicates that there are no inadvertent ties between the station and instrument ground grid systems and that the installation meets design criteria.

Selan, J.C.

1981-06-29

51

A Theoretical Evaluation of Impulse Radar Wave Propagation Through Concrete  

Microsoft Academic Search

It has been shown that one of the most important factors affecting a radar survey of a concrete structure is the operational frequency of the antenna. The operational choice of frequency is difficult as there is always a compromise between signal penetration and resolution. Whilst case histories have proved valuable sources of information, they have not yielded the systematic data

M. C. Forde

1995-01-01

52

4. VIEW NORTHEAST, radar tower (unknown function), prime search radar ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. VIEW NORTHEAST, radar tower (unknown function), prime search radar tower, emergency power building, and height finder radar tower - Fort Custer Military Reservation, P-67 Radar Station, .25 mile north of Dickman Road, east of Clark Road, Battle Creek, Calhoun County, MI

53

5. VIEW EAST, height finder radar towers, radar tower (unknown ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW EAST, height finder radar towers, radar tower (unknown function), prime search radar tower, operations building, and central heating plant - Fort Custer Military Reservation, P-67 Radar Station, .25 mile north of Dickman Road, east of Clark Road, Battle Creek, Calhoun County, MI

54

Evaluation of Radar Rainfall Estimation in Widespread Early Spring Rainfall Events  

NASA Astrophysics Data System (ADS)

Significant discrepancies can exist between actual and estimated rainfall with the interaction of biases and random error being documented in a number of studies. Numerous reports have demonstrated strong scale dependence in the uncertainties or errors in radar rainfall estimation strategies. This study addresses issues of scale, radar-range and uncertainty of weather radar rainfall measurements under early spring conditions. Rainfall measurement analysis is focused on XPOL (mobile X-band dual polarization weather radar) retrievals from late March through early May 2002 in Northeastern Connecticut, US. The applicable XPOL dataset has been refined through attenuation correction, considerations of contamination and vertical profiles adjustment and noise to twelve rainfall events at a base resolution of 300-meter grids every five minutes. XPOL measurements are validated with sixteen raingauges dispersed in the representative 424 km2 Mansfield Watershed at a maximum range of 23 km. The comparison dataset is taken from the NEXRAD stage-III bias adjusted hourly rainfall rates. This specific data is drawn from the most proximal National Weather Service radars in Upton, NY and Boston, MA each over 100 km away, demonstrating gridded rainfall on a 4-kilometer scale. Several statistical evaluations are employed to study the scale effects and cross-platform radar differences. XPOL radar observations are aggregated to coarser spatial grids; in successive aggregations we test the relative error of selected points against raingauge validation. Spatial XPOL data can be matched directly to NEXRAD stage III data thereby giving an indication of the internal variance of NEXRAD pixels. The assimilated internal variability of NEXRAD rain retrievals may offer insight into the bias and uncertainty of the system and information on the radar-gauge comparison uncertainty.

Knox, R. G.; Anagnostou, E. N.

2004-05-01

55

RAT SCAT evaluation of commercially available radar absorbing materials, volume 1  

Microsoft Academic Search

This report summarizes performance evaluation tests on a variety of commercially available thin flexible sheet type radar absorber materials, including both resonant and non-resonant types. A corner reflector test technique was used which allowed test and evaluation of the absorber at both normal incidence and grazing angles out to ninety (90) degrees. Fourteen types of RAM were tested at frequencies

W. Ohara

1976-01-01

56

Terminal Doppler Weather Radar (TDWR) build 5 Test and Evaluation Master Plan (TEMP)  

Microsoft Academic Search

This document presents the Terminal Doppler Weather Radar (TDWR), Build 5 enhancement, Test and Evaluation Master Plan (TEMP). This Build 5 TEMP identifies Operational Test and Evaluation (OT&E) objectives, responsibilities, resources, schedules, and critical test issues. The Build 5 enhancement consists of a Build 5A which provides connectivity to the Low Level Wind Shear Alert System (LLWAS) 2, and a

Elizabeth Turcich; Robert Cranston

1994-01-01

57

Shipboard Radar.  

National Technical Information Service (NTIS)

The navigational radar 'Stvor' is designed for installation on ships of the shipping fleet and also on marine and river boats of low and medium tonnage. A 'Stvor' station enables ships to navigate in zero visibility -- in fog, at night, etc. Because of it...

1968-01-01

58

Technical evaluation of the adequacy of station electric distribution system voltages for the Yankee Rowe Nuclear Power Station  

SciTech Connect

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the Yankee Rowe Nuclear Power Station. The evaluation is to determine if the onsite distribution system, in conjunction with the offsite power sources, has sufficient capacity to automatically start and operate all Class 1E loads within the equipment voltage ratings under certain conditions established by the Nuclear Regulatory Commission. The analysis shows that the station electric distribution system has the capacity and capability to supply voltage to the Class 1E equipment with their design ratings for the worst case loading condition.

Selan, J.C.

1981-05-29

59

Comparison of TRMM precipitation data with a K-Band Radar, Disdrometer and Manual Rain Gauge data during different monsoon seasons at Coastal and High altitude tropical Stations  

NASA Astrophysics Data System (ADS)

TRMM Merged High Quality/Infrared Precipitation estimates obtained from the TRMM `3B-42' algorithm provides high resolution satellite-based rainfall estimates. To understand the reliability of these remote sensing measurements especially over the tropics, "ground-truth" is mandatory. This paper presents such a preliminary comparison carried out for 2 west coast stations Thiruvananthapuram and Kochi; one east coast station Sriharikota (SHAR) and a high altitude station Munnar in the western ghats 40 km just east to Kochi in the peninsular India using a Micro Rain Radar (MRR), Disdrometer and a manual rain gauge. TRMM rain rate is available as 3-hourly data over a 0.25o X 0.25o grid. The analyses have been done for 3-hourly, daily and monthly accumulations. Out of the total number of events (daily data), 79 percentage of the total events could be detected together by the TRMM and disdrometer sensors. The Correlation coefficient for the comparison is ¿0.9, 0.6 and 0.4 respectively for monthly, daily and 3-hourly for pre, southwest and the northeast monsoon periods at all the stations. The poor comparison shown by coastal stations indicate the "coastal-grid effect" due to the land and ocean back-ground emissivity with in the same grid box in the scenario of satellite measurements. The number of events detected by single sensor only is being high indicates that the rainfall is not uniform even over a small grid size of 0.25X0.25 degrees. This suggests the need to have closely knit network of ground stations within the grid.

Harikumar, R.; Sampath, S.; Varikoden, Hamza; G, Mohan Kumar; v, Sasi Kumar; M, Gairola R.

60

Summary of monitoring station component evaluation project 2009-2011.  

SciTech Connect

Sandia National Laboratories (SNL) is regarded as a center for unbiased expertise in testing and evaluation of geophysical sensors and instrumentation for ground-based nuclear explosion monitoring (GNEM) systems. This project will sustain and enhance our component evaluation capabilities. In addition, new sensor technologies that could greatly improve national monitoring system performance will be sought and characterized. This work directly impacts the Ground-based Nuclear Explosion Monitoring mission by verifying that the performance of monitoring station sensors and instrumentation is characterized and suitable to the mission. It enables the operational monitoring agency to deploy instruments of known capability and to have confidence in operational success. This effort will ensure that our evaluation capabilities are maintained for future use.

Hart, Darren M.

2012-02-01

61

Performance evaluation of a W-band monopulse radar in rotorcraft brownout landing aid application  

NASA Astrophysics Data System (ADS)

BAE Systems recently developed a rotorcraft brownout landing aid system technology (BLAST) to satisfy the urgent need for brownout landing capability. BLAST uses a W-band monopulse (MP) radar in conjunction with radar signal processing and synthetic display techniques to paint a three-dimensional (3-D) perspective of the landing zone (LZ) in real time. Innovative radar signal processing techniques are developed to process the radar data and generate target data vectors for 3-D image synthesis and display. Field tests are conducted to characterize the performance of BLAST with MP and non-MP (only using the sum channel of the MP radar) modes in clear and brownout conditions. Data processing and analysis are performed to evaluate the system's performance in terms of visual effect, signal-to-noise ratio (SNR), target height estimation, ground-mapping effect, and false alarm rate. Both MP and non-MP modes reveal abilities to sufficiently display the 3-D volume of the LZ; the former shows advantage over the latter in providing accurate ground mapping and object height determination.

Liu, Guoqing; Yang, Ken; Sykora, Brian; Salha, Imad

2009-05-01

62

Technical Evaluation Report on the Adequacy of Station Electric Distribution System Voltages for the Peach Bottom Atomic Power Station. Units 2 and 3.  

National Technical Information Service (NTIS)

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the Peach Bottom Atomic Power Station, Units 2 and 3. The evaluation is to determine if the onsite distribution system, in conjunction ...

R. L. White

1982-01-01

63

Technical-Evaluation Report on the Adequacy of Station Electric-Distribution-System Voltages for the Nine Mile Point Nuclear Station, Unit 1, (Docket No. 50-220).  

National Technical Information Service (NTIS)

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the Nine Mile Point Nuclear Station, Unit 1. The evaluation is to determine if the onsite distribution system in conjunction with the o...

J. C. Selan

1983-01-01

64

Field Evaluation of the Generalized Maintenance Trainer-Simulator. II. AN/SPA-66 Radar Repeater.  

National Technical Information Service (NTIS)

This is a report of field evaluation of the Generalized Maintenance Trainer-Simulator (GMTS) applied to troubleshooting the AN/SPA-66 Radar Repeater. The GMTS is a relatively low cost, stand-alone system for providing intensive practice in troubleshooting...

J. W. Rigney D. M. Towne P. J. Moran R. A. Mishler

1978-01-01

65

Evaluation of space station ATCS evolution growth paths  

NASA Astrophysics Data System (ADS)

This paper determines the feasibility of potential Active Thermal Control System (ATCS) growth paths by assessing thermal, integration, and implementation impacts. Thermal Radiation Analysis System/Infrared Radiation Transfer (TRASYS/IRTRAN) models were used to evaluate the effects of increased radiator temperature, increased radiator area, and radiator wing addition on Space Station Freedom (SSF) elements, including energy reflected back to the ATCS. Systems Improved Numerical Differencing Analyzer/Fluid Integrator (SINDA/FLUINT) models were used to determine the heat rejection capability of an ATCS loop with an integrated heat pump that operates with Electric Power System (EPS) peak power. The effects of upgrading the ATCS by advanced technology Orbital Replacement Unit (ORU) implementation during maintenance replacements was also evaluated. The study results presented lead to conclusions on which paths are best suited for different growth scenarios.

Ames, Brian E.; Petete, Patricia A.

66

14 CFR Appendix G to Part 121 - Doppler Radar and Inertial Navigation System (INS): Request for Evaluation; Equipment and...  

Code of Federal Regulations, 2010 CFR

Doppler Radar and Inertial Navigation System (INS): Request for Evaluation; Equipment and Equipment Installation; Training Program; Equipment Accuracy and Reliability; Evaluation Program G Appendix G to Part 121 Aeronautics and...

2010-01-01

67

14 CFR Appendix G to Part 121 - Doppler Radar and Inertial Navigation System (INS): Request for Evaluation; Equipment and...  

Code of Federal Regulations, 2010 CFR

Doppler Radar and Inertial Navigation System (INS): Request for Evaluation; Equipment and Equipment Installation; Training Program; Equipment Accuracy and Reliability; Evaluation Program G Appendix G to Part 121 Aeronautics and...

2009-01-01

68

Work Plan and Sampling and Analysis Plan for Interim Remedial Actions for Indian Mountain Long Range Radar Station, Elmendorf AFB, Alaska. Addendum to RI/FS Work Plan (July 1994) and Sampling and Analysis Plan (July 1994).  

National Technical Information Service (NTIS)

The purpose of the report is to describe and detail the activities to be conducted as part of the Interim Remedial Action at Indian Mountain Long Range Radar Station, Alaska. Section 1.0 provides introduction and background information, and states the obj...

1995-01-01

69

Shuttle orbiter Ku-band radar/communications system design evaluation  

NASA Astrophysics Data System (ADS)

Tasks performed in an examination and critique of a Ku-band radar communications system for the shuttle orbiter are reported. Topics cover: (1) Ku-band high gain antenna/widebeam horn design evaluation; (2) evaluation of the Ku-band SPA and EA-1 LRU software; (3) system test evaluation; (4) critical design review and development test evaluation; (5) Ku-band bent pipe channel performance evaluation; (6) Ku-band LRU interchangeability analysis; and (7) deliverable test equipment evaluation. Where discrepancies were found, modifications and improvements to the Ku-band system and the associated test procedures are suggested.

Dodds, J.; Holmes, J.; Huth, G. K.; Iwasaki, R.; Maronde, R.; Polydoros, A.; Weber, C.; Broad, P.

1980-12-01

70

Determination of Space Station on-orbit nondestructive evaluation requirements  

NASA Astrophysics Data System (ADS)

NASA has recently initiated a reassessment of requirements for the performance of in-space nondestructive evaluation (NDE) of the International Space Station Alpha (ISSA) while on- orbit. given the on-orbit operating environment, there is a powerful motivation for avoiding inspection requirements. For example the ISSA maintenance philosophy includes the use of orbital replacement units (ORUs); hardware that is designed to fail without impact on mission assurance or safety. Identification of on-orbit inspection requirements involves review of a complex set of disciplines and considerations such as fracture control, contamination, safety, mission assurance, electrical power, and cost. This paper presents background discussion concerning on-orbit NDE and a technical approach for separating baseline requirements from opportunities.

Salkowski, Charles

1995-07-01

71

Technical evaluation of the adequacy of station electric distribution system voltages for the San Onofre Nuclear Generating Station, Unit 1  

SciTech Connect

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the San Onofre Nuclear Generating Station, Unit. The evaluation is to determine if the onsite distribution system in conjunction with the offsite power sources has sufficient capacity to automatically start and operate all Class 1E loads within the equipment voltage ratings under certain conditions established by the Nuclear Regulatory Commission. The analysis submitted demonstrates that acceptable voltages will be supplied to the Class 1E equipment under worst-case conditions.

Selan, J.C.

1982-01-14

72

Technical evaluation of the adequacy of station electric-distribution-system voltages for the Pilgrim Nuclear Power Station, Unit 1  

SciTech Connect

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the Pilgrim Nuclear Power Station, Unit 1. The evaluation is to determine if the onsite distribution system in conjunction with the offsite power sources has sufficient capacity to automatically start and operate all Class 1E loads within the equipment voltage ratings under certain conditions established by the Nuclear Regulatory Commission. The analyses demonstrated that for the worst case conditions established, the Class 1E equipment will automatically start and continue to operate within the equiment design voltage rating.

Selan, J.C.

1981-12-28

73

Precipitation fields interpolated from gauge stations versus a merged radar-gauge precipitation product: influence on modelled soil moisture at local scale and at SMOS scale  

NASA Astrophysics Data System (ADS)

For the validation of coarse resolution soil moisture products from missions such as the Soil Moisture and Ocean Salinity (SMOS) mission, hydrological modelling of soil moisture is an important tool. The spatial distribution of precipitation is among the most crucial input data for such models. Thus, reliable time series of precipitation fields are required, but these often need to be interpolated from data delivered by scarcely distributed gauge station networks. In this study, a commercial precipitation product derived by Meteomedia AG from merging radar and gauge data is introduced as a novel means of adding the promising area-distributed information given by a radar network to the more accurate, but point-like measurements from a gauge station network. This precipitation product is first validated against an independent gauge station network. Further, the novel precipitation product is assimilated into the hydrological land surface model PROMET for the Upper Danube Catchment in southern Germany, one of the major SMOS calibration and validation sites in Europe. The modelled soil moisture fields are compared to those obtained when the operational interpolation from gauge station data is used to force the model. The results suggest that the assimilation of the novel precipitation product can lead to deviations of modelled soil moisture in the order of 0.15 m3 m-3 on small spatial (∼1 km2) and short temporal resolutions (∼1 day). As expected, after spatial aggregation to the coarser grid on which SMOS data are delivered (~195 km2), these differences are reduced to the order of 0.04 m3 m-3, which is the accuracy benchmark for SMOS. The results of both model runs are compared to brightness temperatures measured by the airborne L-band radiometer EMIRAD during the SMOS Validation Campaign 2010. Both comparisons yield equally good correlations, confirming the model's ability to realistically model soil moisture fields in the test site. The fact that the two model runs perform similarly in the comparison is likely associated with the lack of substantial rain events before the days on which EMIRAD was flown.

Dall'Amico, J. T.; Mauser, W.; Schlenz, F.; Bach, H.

2012-03-01

74

Modelling and assessment of station originated outages for composite systems reliability evaluation  

SciTech Connect

This paper considers the impact that terminal station failure events have on the contingencies of connected lines and generators which should be included in the reliability evaluation of a composite system. It describes algorithms which simulate various failure modes of station components, deduce the resulting contingencies and their reliability indices, group together identical contingencies and cumulate the resulting reliability indices. This is a new approach for determining the effect of station failures on station-originated outages. The results can be used to assess the reliability of the stations themselves and as input data to a composite system reliability evaluation technique.

Allan, R.N.; Ochoa, J.R.

1988-02-01

75

Evaluation of the Interferences of GNSS (Galileo\\/GPS) signals on Air Traffic Control Radar and Wind Profiler Radar  

Microsoft Academic Search

GNSS systems use frequency band close to that of L-band primary surveillance radar for Air Traffic Contro, i.e. 1250-1350 MHz, and of some Wind Profiler Radar (1290 MHz). According to the World Radio Communication Conference 2003 (WRC-03) resolution, in order to protect Aeronautic Radio Navigation System (ARNS) systems, Radio Navigation Satellite System (RNSS) administrations shall ensure that the equivalent power

G. Galati; M. Leonardi; C. Cosenza; F. Lo Zito; F. Gottifredi

2006-01-01

76

State-space adjustment of radar rainfall and skill score evaluation of stochastic volume forecasts in urban drainage systems.  

PubMed

Merging of radar rainfall data with rain gauge measurements is a common approach to overcome problems in deriving rain intensities from radar measurements. We extend an existing approach for adjustment of C-band radar data using state-space models and use the resulting rainfall intensities as input for forecasting outflow from two catchments in the Copenhagen area. Stochastic grey-box models are applied to create the runoff forecasts, providing us with not only a point forecast but also a quantification of the forecast uncertainty. Evaluating the results, we can show that using the adjusted radar data improves runoff forecasts compared with using the original radar data and that rain gauge measurements as forecast input are also outperformed. Combining the data merging approach with short-term rainfall forecasting algorithms may result in further improved runoff forecasts that can be used in real time control. PMID:23925186

Löwe, Roland; Mikkelsen, Peter Steen; Rasmussen, Michael R; Madsen, Henrik

2013-01-01

77

Generalized Radar Output Simulation.  

National Technical Information Service (NTIS)

Using the outputs from the simulation of overall body motion related to observations at a complex of earth stations, this report develops a model for generating the scattering matrix and radar output voltages. The general multistatic case is treated using...

J. F. A. Ormsby S. H. Bickel

1969-01-01

78

Terminal Doppler Weather Radar Build 5A Operational Test and Evaluation (OTE) Integration and OTE Operational Test Plan.  

National Technical Information Service (NTIS)

The Terminal Doppler Weather Radar (TDWR) Build 5A Enhancement Operational Test and Evaluation (OTE) Integration and OTE Operational Test Plan provides the overall philosophy and approach to Build 5A OTE testing, and identifies OTE objectives responsibili...

R. Martinez P. Guthlein S. Viveiros D. Wedge

1994-01-01

79

Site Evaluation for Laser Satellite-Tracking Stations  

Microsoft Academic Search

Twenty-six locations for potential laser satellite-tracking stations, four of them actually already occupied in this role, have been reviewed in terms of their known local and regional geology and geophysics. Laser tracking techniques are now reaching a precision where tectonic motions of station sites can be significant. The chosen sites are scattered over the globe such that every major plate,

N. H. Mao; P. A. Mohr

1976-01-01

80

1. VIEW NORTHWEST, operations building, height finder radar tower, and ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. VIEW NORTHWEST, operations building, height finder radar tower, and radar tower (unknown function) - Fort Custer Military Reservation, P-67 Radar Station, .25 mile north of Dickman Road, east of Clark Road, Battle Creek, Calhoun County, MI

81

A novel method for evaluating robustness of CFAR radar detectors  

Microsoft Academic Search

A method for evaluating the robustness of constant false alarm rate (CFAR) detectors is presented, which is based on the powerful methodology of influence function (IF) developed in the literature on robust statistics. It can evaluate and compare the robustness of different kinds of CFAR detectors by calculating the first derivative of false alarm probability (FAP) at an underlying distribution,

Meng Huadong; Peng Yingning; Wang Xiqin

2002-01-01

82

[Evaluation of medication advertising broadcast on radio stations].  

PubMed

The scope of this paper was to evaluate advertising for medication broadcast on radio stations in Natal, State of Rio Grande do Norte, Brazil, from April to September 2008 and from April to September 2010. The advertising was recorded and transcribed in order to conduct legal analysis and content analysis based on the precepts of Laurence Bardin. Both the advertising recorded during the first stage (regulated by RDC 102/00) and the second stage (regulated by RDC 96/08) contained some form of legal violation. Content analysis detected practically the same violations in both stages, namely the lack of information regarding adverse effects of the medication, appeal to consumption, exaggeration of efficiency/effectiveness and abusive exploitation of illness. Despite the inclusion of more modern and restrictive legislation, radio advertising continues to violate the law blatantly, committing abuse and disrespecting the population's entitlement to good health. The study reveals the need for medication advertising to be dealt with in a broader context, in other words to be treated as a public health concern. It must take into consideration the socio-historical scenario in which it evolved, since the legislation alone is insufficient to combat abuse committed to the detriment of public health. PMID:23358781

Batista, Almária Mariz; Carvalho, Maria Cleide Ribeiro Dantas de

2013-02-01

83

Results of the Kansas City 1989 Terminal Doppler Weather Radar (TDWR) operational evaluation testing  

NASA Astrophysics Data System (ADS)

The Terminal Doppler Weather Radar (TDWR) testbed was used at the Kansas City International (KCI) airport during the summer of 1989. The objective was to test and refine previous tested techniques for the automatic detection of low-altitude wind shear phenomena (specifically microbursts and gun fronts) and heavy precipitation in a midwest weather environment, as well as to assess possible new products such as storm movement predictions. A successful operation evaluation of the TDWR products took place at the KCI tower and terminal radar control room (TRACON). Several supervisor and controller display refinements were assessed as effective. The system was successful in terms of aircraft at KCI avoiding wind shear encounters during the operational period, and it was assessed as very good in usefulness for continuing operation by the KCI air traffic control (ATC) personnel. The probability of detection for microbursts was substantially better than that in Denver. However, the false-alarm probability was found to be substantially higher in Kansas City due to a combination of weather and clutter phenomena. By optimizing the site-adaptation capabilities of the TDWR meteorological and data quality algorithms, the required false-alarm probability was achieved. The gust front performance was generally poorer than in Denver due to a combination of unfavorable radar-airport-gust front geometry of false alarms induced by low-level jets. Gust front algorithm refinements which should provide improved performance are discussed.

Evans, J. E.

1990-08-01

84

Offshore next generation weather radar (NEXRAD) test and evaluation master plan (TEMP)  

NASA Astrophysics Data System (ADS)

This document provides the test philosophy and approach for the Offshore Next Generation Weather Radar (NEXRAD) Test and Evaluation Master Plan (TEMP). The NEXRAD differs from the typical Federal Aviation Administration (FAA) weather radar acquisition in that it is jointly funded by the Department of Defense (DOD), the Department of Commerce (DOC), and the Department of Transportation (DOT). These three agencies chartered the Joint System Program Office (JSPO) to manage the NEXRAD development and subsequent test programs. JSPO has deployed 70 single-channel radar systems across the continental United States (CONUS). The FAA is deploying NEXRAD systems at non-CONUS (offshore) locations such as Alaska, Hawaii, and the Caribbean. The FAA Offshore NEXRAD will have a redundant configuration and a Remote Monitoring Subsystem (EMS). A total of 14 Offshore NEXRAD's will be procured under this acquisition: 3 in the Caribbean, 4 in Hawaii, and 7 in Alaska. Funding constraints will limit the acquisition to seven NEXRAD's in the 1994-1995 timeframe.

Martinez, Radame; Cranston, Robert; Porcello, John

1995-01-01

85

Meteor wind radar observations of tidal amplitudes over a low-latitude station Trivandrum (8.5°N, 77°E): Interannual variability and the effect of background wind on diurnal tidal amplitudes  

Microsoft Academic Search

Based on the horizontal winds measured using SKiYMET meteor wind radar during the period of June 2004–May 2007, the seasonal and interannual variability of the diurnal and semidiurnal amplitudes and phases in the mesospheric and lower thermospheric (MLT) region over a low-latitude station Trivandrum (8.5°N) are investigated. The monthly values of amplitudes and phases are calculated using a composite day

V. Deepa; Geetha Ramkumar; T. Maria Antonita; Karanam Kishore Kumar

2008-01-01

86

Launch delays in the evaluation of Space Station supportability  

NASA Astrophysics Data System (ADS)

The National Space Transportation System (NSTS) will be the sole provider of assembly items and support resources to Space Station Freedom. Using an operations simulation tool, the consequences of spares provisioning levels and launch schedule perturbations to onorbit systems' effectiveness are explored. The extent of post-Challenger launch delay experiences and how they are modeled are described. By using simulation modeling, the operational availability of space station hardware and distinctions in support requirements are investigated for the Mission Build flights, MB-1 through MB-7.

Dejulio, Edmund; Strickland, Christopher; McCormick, James

1991-11-01

87

Evaluation of moisture sensors for NGV fueling station applications. Topical report, November 1994-April 1996  

SciTech Connect

Moisture content in natural gas has become an important issue for compressed natural gas (CNG) fueling stations. The objective of this project was to evaluate the performance of four hygrometer technologies and identify the most cost effective designs suitable for CNG fueling station applications. The four technologies evaluated were: aluminum oxide, ceramic dewpoint, electrolytic, and silicon chip sensors. The hygrometer performance was evaluated with respect to accuracy, response time, repeatability, operating conditions, maintenance requirements, and cost.

Rowley, P.F.; Maniquis, V.T.; Hunecke, D.E.; Blazek, C.F.

1996-08-01

88

Computation of clear-air radar backscatter from numerical simulations of turbulence: 1. Numerical methods and evaluation of biases  

NASA Astrophysics Data System (ADS)

A numerical simulation of secondary instability and turbulence accompanying Kelvin-Helmholtz shear instability and a numerical algorithm computing radar backscatter from these turbulence volumes are employed to examine the validity of routine assumptions employed in radar studies of atmospheric dynamics that rely on backscatter from refractive index fluctuations. The numerical simulation of KH instability describes turbulence dynamics and character from the onset of instability, through fully developed turbulence, to turbulence decay and restratification at late times. Radar backscatter computations employing the Born approximation and the turbulence fields at multiple times are performed for representative radar frequencies, beam widths, and pulse lengths. Vertical velocities obtained from the Doppler spectra are compared with the true velocities evaluated with the same weighting of the true velocity distributions. Results reveal departures of simulated radar velocity estimates that depend on how many scatterers are included in the scattering volume, how their contributions are weighted in space and time, and the morphology of the turbulence field. Biases include underestimates of vertical velocities where velocities and refractive index fluctuations are correlated, apparent velocities due to advection of tilted scatterers, and an inability to define Doppler velocities with precision where turbulence is strong, but backscatter is weak due to mixing and eradication of refractive index gradients. A companion paper employs these procedures to describe the backscatter power and Doppler velocities for two canonical radars throughout the life cycle of the KH instability. Both studies suggest systematic measurement biases that appear to account for a number of reported measurements.

Franke, P. M.; Mahmoud, S.; Raizada, K.; Wan, K.; Fritts, D. C.; Lund, Tom; Werne, J.

2011-11-01

89

Performance Evaluation of MIMO Base Station Antenna Designs  

Microsoft Academic Search

Cellular standards like the third generation partnership program (3GPP) long term evolution (LTE), ultra-mobile broadband (UMB), high speed downlink packet access (HSDPA) and IEEE 802.16e (WiMAX) support multiple-input multiple-output (MIMO) wireless communication technology. MIMO uses multiple antennas at the transmitter and receiver along with advanced digital signal processing to improve link quality and capacity. Existing base station use antenna arrays

Ramya Bhagavatula; Robert W. Heath Jr; Kevin Linehan

90

47 CFR 90.425 - Station identification.  

Code of Federal Regulations, 2011 CFR

...devices which are employed solely as a means of attracting attention, or for remote control purposes, or which is retransmitting...from another radio station or stations. (4) It is any type of radiopositioning or radar station authorized in a...

2011-10-01

91

Findings of the Joint Workshop on Evaluation of Impacts of Space Station Freedom Ground Configurations.  

National Technical Information Service (NTIS)

At the workshop, experts from the plasma interactions community evaluated the impacts of environmental interactions on the Space Station Freedom (SSF) under each of the proposed grounding schemes. The grounding scheme chosen for the SSF power system was f...

D. C. Ferguson D. B. Snyder R. Carruth

1991-01-01

92

Evaluation of Speech Recognizers for Use in Advanced Combat Helicopter Crew Station Research and Development.  

National Technical Information Service (NTIS)

The U.S. Army Crew Station Research and Development Facility uses vintage 1984 speech recognizers. An evaluation was performed of newer off-the-shelf speech recognition devices to determine whether newer technology performance and capabilities are substan...

C. A. Simpson

1990-01-01

93

Millimeter radar  

Microsoft Academic Search

The paper discusses some of the advantages offered by millimeter waves over microwaves, reviews possible and past millimeter radar applications, and looks at some future millimeter radar systems. The coming millimeter radars include radiometric seekers, radiometers, and high resolution radar for satellite identification. Important problems to be resolved before millimeter radars can be put into production include component capability; radar

S. L. Johnston

1977-01-01

94

Statistical evaluation of a radar rainfall system for sewer system management  

NASA Astrophysics Data System (ADS)

Urban areas are faced with mounting demands for managing waste and stormwater for a cleaner environment. Rainfall information is a critical component in efficient management of urban drainage systems. A major water quality impact affecting receiving waterbodies is the discharge of untreated waste and stormwater during precipitation, termed wet weather flow. Elimination or reduction of wet weather flow in metropolitan sewer districts is a major goal of environmental protection agencies and often requires considerable capital improvements. Design of these improvements requires accurate rainfall data in conjunction with monitored wastewater flow data. Characterizing the hydrologic/hydraulic performance of the sewer using distant rain gauges can cause oversizing and wasted expenditures. Advanced technology has improved our ability to measure accurately rainfall over large areas. Weather radar, when combined with rain gauge measurements, provides detailed information concerning rainfall intensities over specific watersheds. Knowing how much rain fell over contributing areas during specific periods aids in characterizing inflow and infiltration to sanitary and combined sewers, calibration of sewer system models, and in operation of predictive real-time control measures. Described herein is the design of a system for managing rainfall information for sewer system management, along with statistical analysis of 60 events from a large metropolitan sewer district. Analysis of the lower quartile rainfall events indicates that the expected average difference is 25.61%. Upper quartile rainfall events have an expected average difference of 17.25%. Rain gauge and radar accumulations are compared and evaluated in relation to specific needs of an urban application. Overall, the events analyzed agree to within ± 8% based on the median average difference between gauge and radar.

Vieux, B. E.; Vieux, J. E.

2005-09-01

95

Evaluation of vapor recovery systems efficiency and personal exposure in service stations in Mexico City.  

PubMed

Results of a field study on the efficiency of vapor recovery systems currently used in gasoline service stations in Mexico City are presented. Nine gasoline stations were studied, representing the several technologies available in Mexico City. The test was applied to a fixed vehicular fleet of approximately 10 private and public service vehicles. Each one of the gasoline service stations tested reported efficiencies above 80% in the recovery of vapor losses from gasoline which is the minimum permissible value by Mexican regulations. Implications to the emissions inventory are discussed. A second goal of this study was to measure the potential exposure of service attendants to three important components of gasoline: benzene; toluene; and xylenes. The influence of spatial location of personnel within the service station was also evaluated by measuring levels of the three compounds both at the refueling area and in the service station office. Results are discussed and compared to a previous study. PMID:12798092

Cruz-Núñez, Xochitl; Hernández-Solís, José M; Ruiz-Suárez, Luis G

2003-06-20

96

Terminal Doppler Weather Radar (TDWR) build 5 Test and Evaluation Master Plan (TEMP)  

NASA Astrophysics Data System (ADS)

This document presents the Terminal Doppler Weather Radar (TDWR), Build 5 enhancement, Test and Evaluation Master Plan (TEMP). This Build 5 TEMP identifies Operational Test and Evaluation (OT&E) objectives, responsibilities, resources, schedules, and critical test issues. The Build 5 enhancement consists of a Build 5A which provides connectivity to the Low Level Wind Shear Alert System (LLWAS) 2, and a Build 5B which provides connectivity to an LLWAS III. Build 5A displays LLWAS 2 wind data along with TDWR hazardous weather data on TDWR Geographic Situation Displays (GSD) and Ribbon Display Terminals (RDT). Build 5B provides additional capabilities such as having a Microburst Shear Integration Algorithm (MSIA), TDWR/LLWAS 3 Integration Algorithm, 15-day archiving and TDWR, LLWAS 2 and LLWAS 3 data integration.

Turcich, Elizabeth; Cranston, Robert

1994-05-01

97

The Retrieval of Ice Water Content from Radar Reflectivity Factor and Temperature and Its Use in Evaluating a Mesoscale Model  

NASA Astrophysics Data System (ADS)

Ice clouds are an important yet largely unvalidated component of weather forecasting and climate models, but radar offers the potential to provide the necessary data to evaluate them. First in this paper, coordinated aircraft in situ measurements and scans by a 3-GHz radar are presented, demonstrating that, for stratiform midlatitude ice clouds, radar reflectivity in the Rayleigh-scattering regime may be reliably calculated from aircraft size spectra if the “Brown and Francis” mass size relationship is used. The comparisons spanned radar reflectivity values from -15 to +20 dBZ, ice water contents (IWCs) from 0.01 to 0.4 g m-3, and median volumetric diameters between 0.2 and 3 mm. In mixed-phase conditions the agreement is much poorer because of the higher-density ice particles present. A large midlatitude aircraft dataset is then used to derive expressions that relate radar reflectivity and temperature to ice water content and visible extinction coefficient. The analysis is an advance over previous work in several ways: the retrievals vary smoothly with both input parameters, different relationships are derived for the common radar frequencies of 3, 35, and 94 GHz, and the problem of retrieving the long-term mean and the horizontal variance of ice cloud parameters is considered separately. It is shown that the dependence on temperature arises because of the temperature dependence of the number concentration “intercept parameter” rather than mean particle size. A comparison is presented of ice water content derived from scanning 3-GHz radar with the values held in the Met Office mesoscale forecast model, for eight precipitating cases spanning 39 h over southern England. It is found that the model predicted mean IWC to within 10% of the observations at temperatures between -30° and -10°C but tended to underestimate it by around a factor of 2 at colder temperatures.

Hogan, Robin J.; Mittermaier, Marion P.; Illingworth, Anthony J.

2006-02-01

98

Radar Experiments Data Reduction, and Experimental Tests.  

National Technical Information Service (NTIS)

Work performed included software support for the evaluation and development of advanced radar antenna systems, development and maintenance of target identification databases, and the data reduction of raw radar data from field tests. Keywords: Radar anten...

W. O. Loescher

1990-01-01

99

51. View of upper radar scanner switch in radar scanner ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

51. View of upper radar scanner switch in radar scanner building 105 from upper catwalk level showing emanating waveguides from upper switch (upper one-fourth of photograph) and emanating waveguides from lower radar scanner switch in vertical runs. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

100

An Evaluation of the Need for and Desired Location of Additional Meteorological Stations in Southwestern North Dakota.  

National Technical Information Service (NTIS)

The study's objectives are to assess the need and identify the desired locations for additional meteorological monitoring stations in Western North Dakota, and to evaluate the need for augmenting the instrumentation at existing stations to provide adequat...

T. Method D. Nantt J. M. Ramirez

1977-01-01

101

Over-ocean Evaluation of a GPM Radar-Radiometer Combined Algorithm Using TRMM-based Synthetic Data  

NASA Astrophysics Data System (ADS)

In this study, the performance of a combined radar-radiometer retrieval algorithm for the Global Precipitation Measurement (GPM) Mission is investigated using synthetic data derived from Tropical Rainfall Measuring Mission (TRMM) observations. The combined retrieval algorithm is based on the generation of an ensemble of dual-frequency radar-only precipitation profile estimates and the calculation of associated microwave brightness temperatures. A statistical analysis of the agreement between calculated and observed brightness temperatures identifies the radar-only estimates that are most consistent with the observed brightness temperatures. Variables that are necessary for the calculation of brightness temperatures but which are not essential in the derivation of the radar-only retrievals are stochastically prescribed and refined based on the agreement between simulated and observed radiometer brightness temperatures. To evaluate this algorithm over oceans, TRMM observations are used. That is, vertical profiles particles size distribution (PSD) intercepts are assumed (one profile per Precipitation Radar (PR) footprint) for a large number of TRMM orbits. A single frequency radar-retrieval algorithm is applied to TRMM PR observations to derive vertical PSD profiles consistent with both the assumed PSD intercepts and the TRMM PR observations. TRMM Microwave Imager (TMI) observations are used to derive surface conditions (i.e. sea surface temperatures and sea surface winds) and parameterized information regarding the vertical distribution of water vapor and clouds in rain-free fields of view (FOVs). The surface conditions in rain FOVs are determined by interpolation of rain-free FOVs. The vertical profiles of water vapor, water and ice clouds are statistically prescribed in rain FOVs. The TMI derived surface conditions, the PR derived PSDs and the statistically prescribed water vapor and cloud profiles are used to synthesize Ka-band radar observations and associated (PR resolution) brightness temperatures at the GMI frequencies. The Ku-band PR observations, the associated Ka-band simulated radar observations, and the simulated GMI observations convolved at the GMI resolution constitute the synthetic observations used to test the GPM combined retrieval algorithm. The precipitation estimates derived from the synthetic observations are compared to reference precipitation assumed in the observation synthesis. Results indicate notably superior performance of the combined algorithm relative to that of a dual-frequency radar-only algorithm.

Grecu, M.; Olson, W.

2011-12-01

102

Region-Enhanced Passive Radar Imaging  

Microsoft Academic Search

Abstract We adapt and apply a recently-developed region-enhanced synthetic aperture radar (SAR) image reconstruction technique to the problem of passive radar imaging. One goal in passive radar imaging is to form images of aircraft using signals transmitted by commercial radio and television stations that are reflected from the objects of interest. This involves reconstructing an image from sparse samples of

Mujdat Cetin; Aaron D. Lanterman

2004-01-01

103

Evaluation of data association techniques in a real multitarget radar tracking environment  

NASA Astrophysics Data System (ADS)

This paper assesses tracking performance of a number of commonly-used data association techniques, including the nearest-neighbor (NN) data association with optimal and sub-optimal assignments, the weighted-average and nearest-neighbor version of the probabilistic data association (PDA), joint probabilistic data association (JPDA), cheap JPDA, and sub-optimal JPDA. The real radar tracking data used for the performance evaluation in this paper contain multiple maneuvering and non-maneuvering air targets in various clutter conditions. The study shows that all the data association methods perform well when the targets are well separated with near straight-line trajectories. In the case of closely spaced and maneuvering targets, the NN and NN version of JPDA methods are more effective than the weighted-average PDA and JPDA methods.

Hu, Zhijian; Leung, Henry; Blanchette, Martin

1995-09-01

104

Remote infrared signage evaluation for transit stations and intersections.  

PubMed

Opportunities for education and employment depend upon effective and independent travel. For mainstream society, this is accomplished to a large extent by printed signs. People who are print disabled, visually impaired, or totally blind are at a disadvantage because they do not have access to signage. Remote infrared signage, such as the Talking Signs (TS) system, provides a solution to this need by labeling the environment for distant viewing. The system uses a transmitting "sign" and a hand-held receiver to tell people about their surroundings. In a seamless infrared signage environment, a visually impaired traveler could: walk safely across an intersection to an ATM or fare machine, from fare machine to bus stop, from bus stop to bus; from bus to building, from building to elevator, from elevator to office, from office to restroom, and so forth. This paper focuses on two problems that are among the most challenging and dangerous faced by blind travelers: negotiating complex transit stations and controlled intersections. We report on human factors studies of TS in these critical tasks, examining such issues as how much training is needed to use the system, its impact on performance and safety, benefits for different population subgroups and user opinions of its value. Results indicate that blind people can quickly and easily learn to use remote infrared signage effectively, and that its use improves travel safety, efficiency, and independence. PMID:10678457

Crandall, W; Brabyn, J; Bentzen, B L; Myers, L

1999-10-01

105

Evaluation of radar precipitation estimates at a range of time scales and methodologies  

Microsoft Academic Search

The most common radar-based quantitative precipitation estimation (QPE) methods are based on power-law relationships between the radar reflectivity and the rain rate. This group of methodologies ranges from a constant relation to a relation in which the power-law multiplicative parameter depends on several factors such as distance from the radar, altitude, etc. A different QPE approach is the window probability

E. Morin; E. Bet-Halachmi

2009-01-01

106

Network planning analysis and data quality evaluation of one way ranging station for irnss  

NASA Astrophysics Data System (ADS)

Indian regional navigation satellite system is an autonomous regional satellite navigation system, developed by Indian Space Research Organisation. IRNSS is under total control of Indian Government. A constellation of seven satellites and a support ground segment is planned under IRNSS. The objective of my project is to design a network for single way ground stations considering the influence of Geometric Dilution of Precision (GDOP), Ionospheric Pierce Points (IPP) and Orbit Determination so that the accuracy of data received from IRNSS satellites is maintained and to evaluate the quality of data from the satellites to ensure its integrity. In GDOP analysis maximum, minimum GDOPS for the constellation are calculated in the service volume that is intended for IRNSS and stations in the region of minimum GDOP could be included in the network of ground stations. In IPP analysis the occurrence of IPP points over the service volume is found and analysis is done to make sure that the entire service volume (divided into grids) has IPP points over it. From the result of this analysis the ground stations that are to be included in the network and also if additional ground stations are required. Also the ground stations must be selected in such a way that the signals received by them have reduced ranging errors. Combining the results of the above said analysis a network of single way ground stations is designed. (Tool used- Matlab, ODTK)

Janani Balasubramaniam, Kirthika

2012-07-01

107

Design and implementation of an experimental GSM based passive radar  

Microsoft Academic Search

Passive radar is a special kind of radar system that utilizes electromagnetic radiation already present in the environment to detect targets as well as estimate target parameters. This paper discusses the use of GSM base station as a non-cooperative illuminator for bistatic passive radar operation. The design and implementation of this novel passive radar system is introduced. Some initial experimental

Hongbo Sun; Danny K. P. Tan; Yilong Lu

2003-01-01

108

Evaluation of Wind Vectors Measured by a Bistatic Doppler Radar Network  

Microsoft Academic Search

By installing and linking additional receivers to a monostatic Doppler radar, several wind components can be measured and combined into a wind vector field. Such a bistatic Doppler radar network was developed in 1993 by the National Center for Atmospheric Research and has been in operation at different research departments. Since then, the accuracy of wind vectors has been investigated

Katja Friedrich; Martin Hagen

2004-01-01

109

Airport Surveillance Radar Initial Evaluation Report, Kunsan AB, Korea, 17 September-12 October 1981.  

National Technical Information Service (NTIS)

This report presents data collected 17 September-12 October 1981 to define the capabilities and limitations of the AN/GPN-20(V) radar facility at Kunsan AB, Korea. This report includes descriptions of the useable radar coverage and tracking capabilities, ...

J. R. Minsterl N. H. Benner

1981-01-01

110

Evaluation of pan evaporation modeling with two different neural networks and weather station data  

NASA Astrophysics Data System (ADS)

This study evaluates neural networks models for estimating daily pan evaporation for inland and coastal stations in Republic of Korea. A multilayer perceptron neural networks model (MLP-NNM) and a cascade correlation neural networks model (CCNNM) are developed for local implementation. Five-input models (MLP 5 and CCNNM 5) are generally found to be the best for local implementation. The optimal neural networks models, including MLP 4, MLP 5, CCNNM 4, and CCNNM 5, perform well for homogeneous (cross-stations 1 and 2) and nonhomogeneous (cross-stations 3 and 4) weather stations. Statistical results of CCNNM are better than those of MLP-NNM during the test period for homogeneous and nonhomogeneous weather stations except for MLP 4 being better in BUS-DAE and POH-DAE, and MLP 5 being better in POH-DAE. Applying the conventional models for the test period, it is found that neural networks models perform better than the conventional models for local, homogeneous, and nonhomogeneous weather stations.

Kim, Sungwon; Singh, Vijay P.; Seo, Youngmin

2013-08-01

111

DORIS radar calibration method  

NASA Astrophysics Data System (ADS)

Following the interest expressed by ESA and FGAN, it was decided to realise some evaluation of the DORIS calibration method with the TIRA radar. This paper, organised in four parts, describes: - the importance of radar calibration in the space debris domain - the principle of the DORIS calibration method - the results obtained with the TIRA FGAN radar using the DORIS reference - the advantages of the DORIS calibration and the future uses of this method in an European exercise involving for the ESA benefit both French and German radars.

Ameline, P.

2001-10-01

112

Ground penetrating radar and direct current resistivity evaluation of the desiccation test cap, Savannah River Site  

SciTech Connect

The Savannah River Site (SRS) has a variety of waste units that may be temporarily or permanently stabilized by closure using an impermeable cover to prevent groundwater infiltration. The placement of an engineered kaolin clay layer over a waste unit is an accepted and economical technique for providing an impermeable cover but the long term stability and integrity of the clay in non-arid conditions is unknown. A simulated kaolin cap has been constructed at the SRA adjacent to the Burial Ground Complex. The cap is designed to evaluate the effects of desiccation on clay integrity, therefore half of the cap is covered with native soil to prevent drying, while the remainder of the cap is exposed. Measurements of the continuing impermeability of a clay cap are difficult because intrusive techniques may locally compromise the structure. Point measurements made to evaluate clay integrity, such as those from grid sampling or coring and made through a soil cover, may miss cracks, joints or fissures, and may not allow for mapping of the lateral extent of elongate features. Because of these problems, a non-invasive technique is needed to map clay integrity, below a soil or vegetation cover, which is capable of moderate to rapid investigation speeds. Two non-intrusive geophysical techniques, direct current resistivity and ground penetrating radar (GPR), have been successful at the SRS in geologically mapping shallow subsurface clay layers. The applicability of each technique in detecting the clay layer in the desiccation test cap and associated anomalies was investigated.

Wyatt, D.E.; Cumbest, R.J.

1996-04-01

113

Rainfall Estimates from Radar, Satellite, Gauge, and Combinations: Intercomparison and Evaluation with Hydrologic Simulations  

NASA Astrophysics Data System (ADS)

Rainfall products from radar, satellite, rain gauges, and combinations (i.e., TRMM, PERSIANN, and NEXRAD) have been evaluated for a season of record rainfall in a heavily instrumented study domain in Oklahoma. Metrics describing algorithm performance are computed at seasonal, daily, and hourly scale, and as a function of rainfall intensity. In the second part of this study, we calibrated the Hydrology Laboratory - Distributed Hydrologic Model (HL-DHM) over the Ft. Cobb basin in OK using a 3-year archive of Micronet rain gauge data and USGS discharge observations. The rainfall estimates (with and without bias correction) from each algorithm were input to the independently calibrated hydrologic model and compared to observed streamflow for a 3-month period. The results indicate the performance of the evaluated rainfall algorithms is highly dependent on spatio-temporal scale and intensity of the storm event; i.e., one size does not fit all. We believe developers of rainfall algorithms can use the results presented in this study to optimize the contribution from available sensors to yield the most skillful multisensor rainfall products. This optimization step should consider the intended application of the rainfall products based on scale and intensity.

Flamig, Z.; Gourley, J. J.; Hong, Y.; Wang, J.

2009-12-01

114

Field Evaluation of Boric Acid and Fipronil-Based Bait Stations Against Adult Mosquitoes  

Microsoft Academic Search

ABSTRA-. The effectiveness of boric acid (1%) and fipronil (0.1%) bait stations in reducing the number of laboratory-reared female Aedes aegypti and Ochlerotarus taeniorhynchus mosquitoes released in outdoor screened cages was evaluated. Both toxicants significantly reduced landing rates of the 2 mosquito species on a human subject. However, no significant reduction in the number of adult mosquitoes caught by counterflow

Rui-De Xue; Arshad Ali; Daniel L. Kline; Donald R. Barnard

2008-01-01

115

RAPID EVALUATION OF ELECTRIC AND MAGNETIC FIELD RADIATED BY BASE STATION ANTENNAS FOR CELLULAR COMMUNICATION  

Microsoft Academic Search

A new technique to rapidly evaluate the safety perimeter of base station antennas is presented in this paper. The technique, based on near-field techniques, allows the determination of the electric and magnetic field almost everywhere around the antenna from a very limited set of measurement data. The reconstruction is achieved with an high level of accuracy. In this paper it

L. Casavola; A. Ziyyat; D. Picard

116

Technical-evaluation report on the adequacy of station electric-distribution-system voltages for the Vermont Yankee Nuclear Power Station. Document No. 50-271  

SciTech Connect

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the Vermont Yankee Nuclear Power Station. The evaluation is to determine if the onsite distribution system, in conjunction with the offsite power sources, has sufficient capacity to automatically start and operate all Class 1E loads within the equipment voltage ratings under certain conditions established by the Nuclear Regulatory Commission. The evaluation finds that the voltage analyses submitted demonstrate that adequate voltage will be supplied to the Class 1E equipment under worst case conditions.

Selan, J.C.

1982-09-03

117

Terminal Doppler Weather Radar (TDWR) Build 5B Operational Test and Evaluation (OT E) Integration and OT E Operational Test Plan.  

National Technical Information Service (NTIS)

The Terminal Doppler Weather Radar (TDWR) Build 5B Enhancement Operational Test and Evaluation (OTE) Integration and OTE Operational Test Plan provides the overall philosophy and approach to Build 5B OTE testing, and identifies OTE objectives, responsibil...

R. Martinez S. Viveiros D. Wedge P. Guthlein

1995-01-01

118

Passive Radar.  

National Technical Information Service (NTIS)

The basic ideas and concepts of one of the newest branches of radar, that of passive radar, are discussed. A great deal of attention is devoted to questions of the use of passive radar by the armed forces. The physical fundamentals of passive radar, and t...

A. G. Nikolaev S. V. Pertsov

1975-01-01

119

Interception of LPI radar signals  

Microsoft Academic Search

Most current radars are designed to transmit short duration pulses with relatively high peak power. These radars can be detected easily by the use of relatively modest EW intercept receivers. Three radar functions (search, anti-ship missile (ASM) seeker, and navigation) are examined to evaluate the effectiveness of potential low probability of intercept (LPI) techniques, such as waveform coding, antenna profile

Jim P. Lee

1991-01-01

120

Development of a relationship between station and grid-box rainday frequencies for climate model evaluation  

SciTech Connect

The validation of climate model simulations creates substantial demands for comprehensive observed climate datasets. These datasets need not only to be historically and geographically extensive, but need also to be describing areally averaged climate, akin to that generated by climate models. This paper addresses on particular difficulty found when attempting to evaluate the daily precipitation characteristics of a global climate model, namely the problem of aggregating daily precipitation characteristics from station to area. Methodologies are developed for estimating the standard deviation and rainday frequency of grid-box mean daily precipitation time series from relatively few individual station time series.

Osborn, T.J.; Hulme, M. [Univ. of East Anglia (United Kingdom)

1997-08-01

121

Algorithm for the Evaluation of Radar Propagation in the Spherical Earth Diffraction Region.  

National Technical Information Service (NTIS)

An efficient method is developed for computing the Airy function and apply this method to the problem of calculating the radar propagation factor for diffraction around smooth sphere, Even for high-altitude antennas, our calculations give accurate results...

M. P. Shatz G. H. Polychronopoulos

1988-01-01

122

Performance Evaluation of an Autonomous Adaptive Base Station that Supports Multiple Wireless Network Systems  

NASA Astrophysics Data System (ADS)

Various wireless systems are being developed to meet users' needs, and the rapid increase in frequency demand that accompanies the increasing popularity of wireless services means that more effective use of frequency resources is urgently needed. However, existing base stations are making no effort to use frequency resources effectively, and cooperation among wireless system base stations is needed to use frequency resources more effectively. Base stations can cooperate more efficiently if they are able to use multiple channels of many wireless systems simultaneously. We propose an autonomous adaptive base station (AABS) that can switch among various wireless systems the way software defined radio (SDR) base stations do. AABS can autonomously select and use the most suitable wireless system on the basis of user traffic and its hardware resources. Moreover, frequency resources are used effectively because AABS prevents unnecessary radio wave transmission when the number of users in the wireless systems decreases. AABS is also suitable for “multi-link communication” because it can use multiple channels of multiple wireless systems simultaneously. We developed AABS prototype and evaluated its performance. Our experimental and computer simulation results show the performance of AABS and its efficiency.

Akabane, Kazunori; Shiba, Hiroyuki; Matsui, Munehiro; Uehara, Kazuhiro

123

Evaluating some factors that affect feasility of using ground penetrating radar for landmine detection  

Microsoft Academic Search

Ground penetrating radar (GPR) is one of the promising technologies that can be used to detect landmines. Many factors may\\u000a affect the ability of GPR to detect landmines. Among those factors are: 1) the type of landmine material (metallic or plastic),\\u000a 2) conditions of the host soil (soil texture and soil moisture), and 3) the radar frequency utilized. The impact

Mohamed Metwaly; Ahmed Ismail; Jun Matsushima

2007-01-01

124

Technical-evaluation report on the adequacy of station electric-distribution-system voltages for the San Onofre Nuclear Generating Station, Unit 1. Document No. 50-206  

SciTech Connect

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the San Onofre Nuclear Generating Station, Unit 1. The evaluation is to determine if the onsite distribution system in conjunction with the offsite power sources has sufficient capacity to automatically start and operate all Class 1E loads within the equipment voltage ratings under certain conditions established by the Nuclear Regulatory Commission. The analysis submitted demonstrates that acceptable voltages will be supplied to the Class 1E equipment under worstcase conditions.

Selan, J.C.

1982-09-08

125

Field evaluation of boric acid- and fipronil-based bait stations against adult mosquitoes.  

PubMed

The effectiveness of boric acid (1%) and fipronil (0.1%) bait stations in reducing the number of laboratory-reared female Aedes aegypti and Ochlerotatus taeniorhynchus mosquitoes released in outdoor screened cages was evaluated. Both toxicants significantly reduced landing rates of the 2 mosquito species on a human subject. However, no significant reduction in the number of adult mosquitoes caught by counterflow geometry (CFG) traps baited with CO2 was observed in the boric acid- and fipronil-treated cages compared with control cage. The 2 bait stations were further evaluated against natural populations of adult mosquitoes in 3 residential yards (each ca. 0.8 ha) in St. Johns County, FL. Both bait stations failed to significantly reduce counts of female mosquitoes landing on a human subject; and the capture rates of adult mosquitoes by CFG traps baited with dry ice in bait-treated and control experimental yards were not significantly different. Further field research is needed on the density and placement of bait stations in order to determine their utility in adult mosquito control programs. PMID:18939695

Xue, Rui-De; Ali, Arshad; Kline, Daniel L; Barnard, Donald R

2008-09-01

126

Application of HF radar currents to oil spill modelling.  

PubMed

In this work, the benefits of high-frequency (HF) radar currents for oil spill modeling and trajectory analysis of floating objects are analyzed. The HF radar performance is evaluated by means of comparison between a drifter buoy trajectory and the one simulated using a Lagrangian trajectory model. A methodology to optimize the transport model performance and to calculate the search area of the predicted positions is proposed. This method is applied to data collected during the Galicia HF Radar Experience. This experiment was carried out to explore the capabilities of this technology for operational monitoring along the Spanish coast. Two long-range HF radar stations were installed and operated between November 2005 and February 2006 on the Galician coast. In addition, a drifter buoy was released inside the coverage area of the radar. The HF radar currents, as well as numerical wind data were used to simulate the buoy trajectory using the TESEO oil spill transport model. In order to evaluate the contribution of HF radar currents to trajectory analysis, two simulation alternatives were carried out. In the first one, wind data were used to simulate the motion of the buoy. In the second alternative, surface currents from the HF radar were also taken into account. For each alternative, the model was calibrated by means of the global optimization algorithm SCEM-UA (Shuffled Complex Evolution Metropolis) in order to obtain the probability density function of the model parameters. The buoy trajectory was computed for 24h intervals using a Monte Carlo approach based on the results provided in the calibration process. A bivariate kernel estimator was applied to determine the 95% confidence areas. The analysis performed showed that simulated trajectories integrating HF radar currents are more accurate than those obtained considering only wind numerical data. After a 24h period, the error in the final simulated position improves using HF radar currents. Averaging the information from all the simulated daily periods, the mean search and rescue area calculated using HF radar currents, is reduced by approximately a 62% in comparison with the search area calculated without these data. These results show the positive contribution of HF radar currents for trajectory analysis, and demonstrate that these data combined with atmospheric forecast models, are of value for trajectory analysis of oil spills or floating objects. PMID:18996546

Abascal, Ana J; Castanedo, Sonia; Medina, Raul; Losada, Inigo J; Alvarez-Fanjul, Enrique

2008-11-08

127

Technical evaluation of the proposed technical specification change for the Arkansas Nuclear Power Station, Unit 2  

SciTech Connect

This report documents the technical evaluation of the request for changes in the Technical Specifications for the Arkansas Nuclear Power Station, Unit 2. These changes were proposed by the licensee in a letter dated November 27, 1979. The basis for review included a report entitled Determination of Plant System Trip Setpoints Valves. The requested changes to the Technical Specifications were found to be acceptable based on information submitted by the licensee.

Victor, R.A.

1980-08-01

128

Evaluation of station keeping systems for deepwater drilling semi-submersibles  

Microsoft Academic Search

This paper addresses the need for systematic evaluation of the station keeping systems of deepwater drilling semi-submersibles.\\u000a Based on the selected drilling semi-submersible configuration, the mooring systems were analyzed and designed for a range\\u000a of water depths using different mooring line materials. These were steel wire rope, polyester rope and HMPE (high modulus\\u000a poly ethylene). The mooring analysis was carried

An-Ke Song; Li-Ping Sun; Yong Luo; Qiang Wang

2010-01-01

129

Passive Radar.  

National Technical Information Service (NTIS)

This book sets forth in brief the physical principles of passive radar, describes the functional diagrams and circuit peculiarities of the apparatus, and offers recommendations for modifying radar receivers to adapt them for receiving natural radio-freque...

A. G. Nikolaev S. V. Pertsov

1975-01-01

130

Performance evaluation of the retrieval of a two hours rainfall event through microwave tomography applied to a network of radio-base stations  

NASA Astrophysics Data System (ADS)

Critical precipitation events occurred over the Italian territory have been often characterized by high intensity and very fast development, frequently over small catchment areas. The detection of this kind of phenomena is a major issue that poses remarkable problems that cannot be tackled completely only with 'standard' instrumentation (even when available), such as a weather radars or raingauges. Indeed, the rainfall sampling modalities of these instruments may jeopardize the attempts to provide a sufficiently fast risk alert: - the point-like, time-integrated way of sampling of raingauges can completely/partially miss local rainfall cores of high intensity developing in the neighborhoods. Moreover, raingauges provide cumulated rainfall measurements intrinsically affected by a time delay. - In the case of weather radars, several factors may limit the advantages brought by range resolution and instantaneous sampling: precipitation might be sampled at an excessive height due to the distance of the radar site and/or the orography surrounding the valleys/catchments where the aforementioned kind of events is more likely to form up; distance may limit the resolution in the cross-range direction; beam screening due to orography causes a loss of power that is interpreted in the farther range bins as a reduced precipitation intensity. In this context, a positive role for flagging the criticality of a precipitation event can be played by signal attenuation measurements made along microwave links, as available through the infrastructure of a mobile communications network. Three are the interesting features of such networks: 1) the communications among radio-base stations occur where point-to-point electromagnetic visibility is guaranteed, namely along valleys or between tops/flanks of hills or mountains; 2) the extension of these links (few kilometres) is perfectly compatible with the detection of severe but localized precipitation events; 3) measurements can be made on a practically continuous-time basis. In the past years, we showed that new scenarios for tomographic rainfall monitoring have been disclosed by the availability of widespread networks of radio-base stations for mobile communications (i.e., GSM, GPRS, UMTS). Such networks could be employed as the backbone of a low cost system able to provide 2D estimates of rainfall in real time. Monitoring capabilities increase in more populated sites, as urban areas, where such radio links form up a dense network that can be exploited to get detailed information also about structure and evolution of rainfall phenomena. In 2010, we presented a novel tomographic processing method for rainfall rate estimation, specifically adaptable to the dense and asymmetric topologies of urban networks of radio-base stations. In this paper, we show its application to a simulated time sequence of specific attenuation (K) maps, derived from true weather radar data gathered during a rainfall event specifically selected to evaluate the performance of the tomographic retrieval in critical conditions. The event was in fact very localized and intense and lasted two hours. 12 GHz is assumed for the carrier frequency of the radio-base network. We show the reconstruction performance of the 2D K fields achieved resorting first to a symmetric, regular network and then to a couple of totally asymmetric ones.

Facheris, L.; Cuccoli, F.; Baldini, L.

2012-04-01

131

Millimeter wave radar - Quo vadis in the 1990s?  

NASA Astrophysics Data System (ADS)

Developments in K(a)-band and millimeter wave radars since 1978 are examined. The advantages of millimeter wave radars are discussed and recently developed military and civilian K(a)-band and millimeter wave radars are described. The technological and cost limitations to the development of future millimeter wave radars are considered and the prospects for future millimeter wave radar developments are evaluated.

Johnston, Stephen L.

132

Description and Initial Evaluation of a Computer-Based Individual Trainer for the Radar Intercept Observer.  

ERIC Educational Resources Information Center

|An individual trainer for giving students in the radar intercept observer (RIO) schools concentrated practice in procedures for air-to-air intercepts was designed around a programmable graphics terminal with two integral minicomputers and 8k of core memory. The trainer automatically administers practice in computing values of variables in the…

Rigney, Joseph W.; And Others

133

Shuttle radar topography mission accuracy assessment and evaluation for hydrologic modeling  

Microsoft Academic Search

Digital Elevation Models (DEMs) are increasingly used even in low relief landscapes for multiple mapping applications and modeling approaches such as surface hydrology, flood risk mapping, agricultural suitability, and generation of topographic attributes. The National Aeronautics and Space Administration (NASA) has produced a nearly global database of highly accurate elevation data, the Shuttle Radar Topography Mission (SRTM) DEM. The main

Pablo Alberto Mercuri

2005-01-01

134

Performance evaluation of conducting polymer paints as radar absorbing materials (RAM)  

Microsoft Academic Search

The efficiency and performance of recently developed RAM (radar absorbing materials) based on conducting polymer paints has been investigated in the range of 8-12 GHz. The used conducting polymer in the paint formulations is the polyaniline doped with two different acids: dodecylbenzene sulfonic acid (DBSA), and camphorsulfonic acid (CSA). In practice, RAM ought to be effective over a range of

R. S. Biscaro; E. L. Nohara; G. G. Peixoto; R. Faez; M. C. Rezende

2003-01-01

135

Results of the Kansas City 1989 Terminal Doppler Weather Radar (TDWR) operational evaluation testing  

Microsoft Academic Search

The Terminal Doppler Weather Radar (TDWR) testbed was used at the Kansas City International (KCI) airport during the summer of 1989. The objective was to test and refine previous tested techniques for the automatic detection of low-altitude wind shear phenomena (specifically microbursts and gun fronts) and heavy precipitation in a midwest weather environment, as well as to assess possible new

J. E. Evans

1990-01-01

136

Filtering of radar images based on blind evaluation of noise characteristics  

NASA Astrophysics Data System (ADS)

A common assumption concerning noise in radar images is that it is of multiplicative nature and spatially uncorrelated. Meanwhile, recent studies have shown that additive noise component cannot be neglected, especially for images formed by side look aperture radars (SLARs). Moreover, majority of radar image filtering techniques are designed under assumption that noise is i.i.d., i.e. spatially uncorrelated. However, in many practical situations the latter assumption is not true. Besides, spatial correlation properties of noise can be different and they are often a priori unknown. In this paper we demonstrate that complex statistical and spatial correlation characteristics of noise in radar images can and should be taken into consideration at image filtering stage. We design a modification of the denoising algorithm based on discrete cosine transform (DCT) that is able to easily incorporate a priori information or obtained estimates of noise statistical and spatial correlation characteristics. This can be done in automatic (blind) manner due to utilizing a sequence of blind estimation operations. We present simulation results that show appropriate accuracy and robustness of these operations. Finally, real life image filtering examples are given that confirm the effectiveness of the designed techniques.

Lukin, Vladimir V.; Ponomarenko, Nikolay N.; Abramov, Sergey K.; Vozel, Benoit; Chehdi, Kacem; Astola, Jaakko T.

2008-10-01

137

Evaluation of Hyperspectral, Infrared Temperature and Radar Measurements for Monitoring Surface Soil Moisture  

Microsoft Academic Search

Remote sensing techniques for monitoring soil moisture were tested by comparing hyperspectral reflectance and spectral indexes; surface temperature (Ts) and thermal indexes; and normalized radar backscatter to soil moisture. A laboratory study indicated that hyperspectral reflectance and Ts were sensitive to surface soil moisture (r2 range from 0.72

Ross Bryant; David Thoma; Susan Moran; Chandra Holifield; David Goodrich; Tim Keefer; Ginger Paige

138

Microburst Wind Structure and Evaluation of Doppler Radar for Airport Wind Shear Detection.  

NASA Astrophysics Data System (ADS)

Doppler weather radar data from the Joint Airport Weather Studies (JAWS) Project are used to determine the horizontal and vertical structure of airflow within microbursts. Typically, the associated downdraft is about 1 km wide and begins to spread horizontally at a height below 1 km. The median time from initial divergence at the surface to maximum differential wind velocity across the microburst is 5 min. The height of maximum differential velocity is 75 m. The median velocity differential is 22 m s1 over an average distance of 3.1 km. The outflow is asymmetric, averaging twice as strong along the maximum shear axis compared to the minimum axis.Doppler radar could be an effective means for identifying microbursts and warning aircraft of wind shear hazards. For microburst detection such a radar must be able to measure wind velocities in clear air as well as in heavy rain and hail. Scan update rates should be approximately every 2 min and the lowest few hundred meters of the atmosphere must be observed. Ground clutter must be considerably reduced from levels typically obtained with present Doppler radars. New antenna technology and signal processing techniques may solve this problem. Automated range and velocity unfolding is required, as well as automated identification and dissemination techniques.

Wilson, James W.; Roberts, Rita D.; Kessinger, Cathy; McCarthy, John

1984-06-01

139

The ATC evaluation of the prototype Airport Surveillance Radar Wind Shear Processor (ASR-WSP) at Orlando International Airport  

NASA Astrophysics Data System (ADS)

The Airport Surveillance Radar Wind Shear Processor (ASR-WSP), also known as Airport Surveillance Radar-9 (ASR-9) modification for low altitude wind shear detection, is a production ASR-9 with an expanded weather channel for added processing capabilities. The primary mission of the ASR-WSP is to enhance the safety of air travel through the timely detection and reporting of hazardous wind shear in and near the terminal approach and departure zones of the airport. It will also improve the management of air traffic (AT) in the terminal area through the forecast of precipitation, and ultimately the detection of other hazardous weather phenomena. The ASR-WSP may be used as a stand-alone system at airports without a Terminal Doppler Weather Radar (TDWR) or Enhanced-Low Level Wind Shear Alert System (E-LLWAS), or in an integrated mode with either or both the TDWR and E-LLWAS. An operational evaluation of a prototype ASR-WSP, developed by Massachusetts Institute of Technology Lincoln Laboratories (MIT/LL), was conducted at the Orlando International Airport (MCO) in Orlando, Florida, during the period 29 Jun. to 31 Aug. 1992. The objective of the evaluation was to obtain Federal Aviation Administration (FAA) air traffic controller reaction to the prototype ASR-WSP weather data and display equipment. The following are highlights of the evaluation: (1) the ASW-WSP is very useful when making runway configuration changes; (2) the ASR-WSP is not perceived to be as accurate as the prototype TDWR; (3) the gust front prediction feature is not reliable; and (4) the information provided on both the RDT and the GSD is very useful.

Martinez, Radame

1993-03-01

140

Efficiency evaluation of ground-penetrating radar by the results of measurement of dielectric properties of soils  

NASA Astrophysics Data System (ADS)

The work considers the depth evaluation of ground penetrating radar (GPR) surveys using the attenuation factor of electromagnetic radiation in a medium. A method of determining the attenuation factor of low-conductive non-magnetic soils is developed based on the results of direct measurements of permittivity and conductivity of soils in the range of typical frequencies of GPR. The method relies on measuring the shift and width of the resonance line after a soil sample is being placed into a tunable cavity resonator. The advantage of this method is the preservation of soil structure during the measurement.

Khakiev, Zelimkhan; Kislitsa, Konstantin; Yavna, Victor

2012-12-01

141

Efficiency evaluation of ground-penetrating radar by the results of measurement of dielectric properties of soils  

SciTech Connect

The work considers the depth evaluation of ground penetrating radar (GPR) surveys using the attenuation factor of electromagnetic radiation in a medium. A method of determining the attenuation factor of low-conductive non-magnetic soils is developed based on the results of direct measurements of permittivity and conductivity of soils in the range of typical frequencies of GPR. The method relies on measuring the shift and width of the resonance line after a soil sample is being placed into a tunable cavity resonator. The advantage of this method is the preservation of soil structure during the measurement.

Khakiev, Zelimkhan; Kislitsa, Konstantin; Yavna, Victor [Rostov State Transport University, Rostov-on-Don (Russian Federation)

2012-12-15

142

Safety Evaluation Report Related to the Licence Renewal of Oyster Creek Generating Station. Docket No. 50-219. Volume One.  

National Technical Information Service (NTIS)

This safety evaluation report (SER) documents the technical review of the Oyster Creek Generating Station (OCGS) license renewal application (LRA) by the staff of the United States (US) Nuclear Regulatory Commission (NRC) (the staff). By letter dated July...

2007-01-01

143

Safety Evaluation Report Related to the Licence Renewal of Oyster Creek Generating Station. Docket No. 50-219. Volume Two.  

National Technical Information Service (NTIS)

This safety evaluation report (SER) documents the technical review of the Oyster Creek Generating Station (OCGS) license renewal application (LRA) by the staff of the United States (US) Nuclear Regulatory Commission (NRC) (the staff). By letter dated July...

2007-01-01

144

Safety Evaluation Report: Related to the License Renewal of Vermont Yankee Nuclear Power Station, Docket No. 50-271.  

National Technical Information Service (NTIS)

This document is a supplemental Safety Evaluation Report (SSER) for the License Renewal Application for Vermont Yankee Nuclear Power Station (VYNPS) as Filed by Entergy Nuclear Operation, Inc. and Entergy Nuclear Vermont Yankee, LLC. (Entergy or the Appli...

2009-01-01

145

Safety Evaluation Report: Related to the License Renewal of Vermont Yankee Nuclear Power Station. Docket No. 50-271.  

National Technical Information Service (NTIS)

This safety evaluation report (SER) documents the technical review of the Vermont Yankees Nuclear Power Station (VYNPS) license renewal application (LRA) by the United States (US) Nuclear Regulatory Commission (NRC) staff (the staff). By letter dated Janu...

2008-01-01

146

Feasibility analysis of GSM signal for passive radar  

Microsoft Academic Search

Passive radar makes use of an 'illuminator of opportunity' already present in the environment for other purposes (TV transmission, broadcast systems, etc) to detect targets as well as estimating target parameters. This radar has the merit of being a completely covert radar system, which does not advertise the presence of either the receivers or transmitting stations. One such existing radio

Danny K. P. Tan; Hongbo Sun; Yilong Lu; Weixian Liu

2003-01-01

147

EMP (electro-magnetic pulse) hardening of a relocatable radar  

Microsoft Academic Search

The problem of ensuring radar survivability in a HEMP (high-altitude electromagnetic pulse) environment is examined with particular reference to experimental results obtained for the relocatable TRS 22XX radar. The approach used here is global hardening, whereby the whole system except the antenna is enclosed in a Faraday cage. Every penetration of the radar station is protected, the energy input is

G. J. Deville

1987-01-01

148

Systematic evaluation of NASA precipitation radar estimates using NOAA/NSSL National Mosaic QPE products  

NASA Astrophysics Data System (ADS)

Proper characterization of the error structure of TRMM Precipitation Radar (PR) quantitative precipitation estimation (QPE) is needed for their use in TRMM combined products, water budget studies and hydrological modeling applications. Due to the variety of sources of error in spaceborne radar QPE (attenuation of the radar signal, influence of land surface, impact of off-nadir viewing angle, etc.) and the impact of correction algorithms, the problem is addressed by comparison of PR QPEs with reference values derived from ground-based measurements (GV) using NOAA/NSSL's National Mosaic QPE (NMQ) system. An investigation of this subject has been carried out at the PR estimation scale (instantaneous and 5 km) on the basis of a 3-month-long data sample. A significant effort has been carried out to derive a bias-corrected, robust reference rainfall source from NMQ. The GV processing details will be presented along with preliminary results of PR's error characteristics using contingency table statistics, probability distribution comparisons, scatter plots, semi-variograms, and systematic biases and random errors.

Kirstetter, P.; Hong, Y.; Gourley, J. J.; Chen, S.; Flamig, Z.; Zhang, J.; Howard, K.; Petersen, W. A.

2011-12-01

149

14 CFR Appendix G to Part 121 - Doppler Radar and Inertial Navigation System (INS): Request for Evaluation; Equipment and...  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Doppler Radar and Inertial Navigation System (INS): Request...Appendix G to Part 121âDoppler Radar and Inertial Navigation System (INS): Request...for authority to use a Doppler Radar or Inertial Navigation System must submit a...

2013-01-01

150

Evaluation of auxiliary tempering pump effectiveness at Chalk Point Steam Electric Station  

SciTech Connect

The effectiveness of auxiliary tempering pump operation at Chalk Point Steam Electric Station (SES) at reducing plant-induced mortality of aquatic biota was evaluated. Several Representative Important Species (RIS) and dominant benthic and zooplankton species were used in the evaluation as indicators of overall system-wide responses. Expected mortality with and without auxiliary pump operation was estimated using thermal tolerance data available from the scientific literature for blue crabs, white perch, striped bass, spot, Macoma balthica and Acartia tonsa. The evaluation led to the conclusion that the operation of auxiliary tempering pumps at Chalk Point SES increases plant-induced mortality of spot, white perch, striped bass, and zooplankton. Operation of the tempering pumps may reduce blue crab mortality slightly under certain circumstances, and Macoma balthica mortality is probably largely unaffected by their operation.

Wendling, L.C.; Holland, A.F.

1989-08-01

151

Range Delay Techniques for Radar Target Simulators.  

National Technical Information Service (NTIS)

It was recognized that the Radar Guided Seeker and countermeasure development using flight tests as a primary evaluation tool is costly and insecure from interception of signal and telemetry emenations. Radar Target Simulators were developed which provide...

L. C. Buse

1988-01-01

152

Performance evaluation of ExiStation HBV diagnostic system for hepatitis B virus DNA quantitation.  

PubMed

The performance of a recently developed real-time PCR system, the ExiStation HBV diagnostic system, for quantitation of hepatitis B virus (HBV) in human blood was evaluated. The detection limit, reproducibility, cross-reactivity, and interference were evaluated as measures of analytical performance. For the comparison study, 100 HBV-positive blood samples and 100 HBV-negative samples from Korean Blood Bank Serum were used, and the results of the ExiStation HBV system showed good correlation with those obtained using the Cobas TaqMan (r(2)=0.9931) and Abbott real-time PCR systems (r(2)=0.9894). The lower limit of detection was measured as 9.55IU/mL using WHO standards and the dynamic range was linear from 6.68 to 6.68×10(9)IU/mL using cloned plasmids. The within-run coefficient of variation (CV) was 9.4%, 2.1%, and 1.1%, and the total CV was 11.8%, 3.6%, and 1.7% at a concentration of 1.92log10IU/mL, 3.88log10IU/mL, and 6.84log10IU/mL, respectively. No cross-reactivity or interference was detected. The ExiStation HBV diagnostic system showed satisfactory analytical sensitivity, excellent reproducibility, no cross-reactivity, no interference, and high agreement with the Cobas TaqMan and Abbott real-time PCR systems, and is therefore a useful tool for the detection and monitoring of HBV infection. PMID:23892129

Cha, Young Joo; Yoo, Soo Jin; Sohn, Yong-Hak; Kim, Hyun Soo

2013-07-25

153

Evaluation of 1D numerical models in the prediction of distributed flow series constrained by radar altimetry data  

NASA Astrophysics Data System (ADS)

Recently, efforts have been done forward the development of methodologies to obtain flow estimates from time series of water height at virtual stations (VS - intersections between satellite tracks and water surfaces) from Topex/Poseidon (TP) and ENVISAT radar mission measurements. Relatively simple 1D propagation models such as Muskingum-Cunge (M-C) Routing Model have presented good results in the water flow propagation in Amazonian rivers. These regions suffer, in most cases, of lack of information witch constrains more accurate hydrologic and hydraulic studies. Nevertheless, these M-C models make a lot of simplification witch may cause the lost of important information that these quasi-ungaged basins can offer. This paper presents a comparison between two propagation models to the estimation of water flow series constrained by T/P and ENVISAT data. The models are: ProGUM, a Muskingum-Cunge flow routing model with diffusion-cum-dynamic wave propagation, and HEC-RAS, a well-known 1D hydrodynamic model. The verification was made in four reaches in the Negro River Basin. Each of these reaches are limited by two gauge stations, one upstream and the other one downstream. A total of five VS distributed over the reaches were analyzed. Previous studies have shown that ProGUM may yield errors less then 10% in validation phases. Here, it is demonstrated that, no much improvements can be achieved by using a more complete model capable to absorb the available data and simplifications of a M-C Model do not make significant modifications in the results of rating curve generation from satellite altimetry.

Getirana, A. C.; Bonnet, M.; Roux, E.; Rotunno, O. C.

2007-12-01

154

Radar observables  

NASA Astrophysics Data System (ADS)

A comprehensive account is given of missile design considerations relevant to the prediction, control, and measurement of airframe radar cross sections (RCSs), with a view to the minimization of missile observability. RCS reduction may proceed through airframe shaping to deflect incident radar emissions, as well as through the use of radar-absorbing surface materials and the devision of active radar signal-cancellation methods; some combination of these is often required, due to the deficiencies of any one method. The interaction of all RCS-reduction methods with airframe aerodynamic-design criteria are stressed.

Knott, Eugene F.

155

Evaluation of ionospheric densities using coincident OII 83.4 nm airglow and the Millstone Hill Radar  

NASA Astrophysics Data System (ADS)

We test the utility of the OII 83.4 nm emission feature as a measure of ionospheric parameters. Observed with the Remote Atmospheric and Ionospheric Detection System (RAIDS) Extreme Ultraviolet Spectrograph on the International Space Station (ISS), limb profiles of 83.4 nm emissions are compared to predicted dayglow emission profiles from a theoretical model incorporating ground-based electron density profiles measured by the Millstone Hill radar and parameterized by a best-fit Chapman-? function. Observations and models are compared for periods of conjunction between Millstone Hill and the RAIDS fields-of-view. These RAIDS observations show distinct differences in topside morphology between two days, 15 January and 10 March 2010, closely matching the forward model morphology and demonstrating that 83.4 nm emission is sensitive to changes in the ionospheric density profile from the 340 km altitude of the ISS during solar minimum. We find no significant difference between 83.4 nm emission profiles modeled assuming a constant scale height Chapman-? best-fit to the ISR measurements and those assuming varying scale height.

Douglas, E. S.; Smith, S. M.; Stephan, A. W.; Cashman, L.; Bishop, R. L.; Budzien, S. A.; Christensen, A. B.; Hecht, J. H.; Chakrabarti, S.

2012-05-01

156

Radar-based Flood Warning System for Houston, Texas and Its Performance Evaluation  

NASA Astrophysics Data System (ADS)

Houston has a long history of flooding problems as a serious nature. For instance, Houstonians suffered from severe flood inundation during Tropical Storm Allison in 2001 and Hurricane Ike in 2008. Radar-based flood warning systems as non-structural tools to provide accurate and timely warnings to the public and private entities are greatly needed for urban areas prone to flash floods. Fortunately, the advent of GIS, radar-based rainfall estimation using NEXRAD, and real-time delivery systems on the internet have allowed flood alert systems to provide important advanced warning of impending flood conditions. Thus, emergency personnel can take proper steps to mitigate against catastrophic losses. The Rice and Texas Medical Center (TMC) Flood Alert System (FAS2) has been delivering warning information with 2 to 3 hours of lead time to facility personnel in a readily understood format for more than 40 events since 1997. The system performed well during these major rainfall events with R square value of 93%. The current system has been improved by incorporating a new hydraulic prediction tool - FloodPlain Map Library (FPML). The FPML module aims to provide visualized information such as floodplain maps and water surface elevations instead of just showing hydrographs in real time based on NEXRAD radar rainfall data. During Hurricane Ike (September, 2008), FAS2 successfully provided precise and timely flood warning information to TMC with the peak flow difference of 3.6% and the volume difference of 5.6%; timing was excellent for this double-peaked event. With the funding from the Texas Department of Transportation, a similar flood warning system has been developed at a critical transportation pass along Highway 288 in Houston, Texas. In order to enable emergency personnel to begin flood preparation with as much lead time as possible, FAS2 is being used as a prototype to develop warning system for other flood-prone areas such as City of Sugar Land.

Fang, N.; Bedient, P.

2009-12-01

157

Using an Airborne Doppler Lidar to Evaluate QuikSCAT and RadarSat Derived Winds  

NASA Astrophysics Data System (ADS)

While near surface winds derived from space-based remote sensing have proven very useful, both operationally and for research, there remain several issues not fully resolved. Besides the persistent wind direction uncertainty, high wind speeds (> 25 m/s) and organized circulations such as those associated with large marine atmospheric boundary layer eddies continue to introduce magnitude and representativeness errors in the data products. The US Navy and the Integrated Program Office of NPOESS have jointly sponsored the installation and use of a scanning Doppler wind lidar on a Navy Twin Otter aircraft. The lidar is a 2 micron coherent system with a side door mounted hemispherical scanner. Returns from aerosols are processed to obtain wind profiles (above and below flight level). The measurement accuracy is on the order of a few cm/sec in speed and a degree or two in direction. The footprint of the lidar beam is < 1 meter and the full profiles are constructed with wind observations over a one l kilometer flight segment. The vertical resolution is usually < 50 meters. In the nadir looking mode, the Doppler lidar can resolve wave structures with < 5 cm/sec vertical motion accuracy and with .5 meter horizontal resolution. In the Spring of 2002, the lidar was flown over Monterey Bay (CA)during QuikSCAT and RadarSat overpasses. Cloud streets were observed from the aircraft and with the lidar in the vicinity of organized patterns in the RadarSAT returns. The lidar data offer detailed insight into the velocity and aerosol structures within the larger footprints of the space-based sensors. Detailed analyses of the collocated lidar, QuikScat and RadarSat data will be presented along with plans for the future use of this new research facility.

Emmitt, G. D.; O'Handley, C.; Brown, R. A.; Foster, R.

2002-12-01

158

Evaluation of cloud microphysics schemes in simulations of a winter storm using radar and radiometer measurements  

NASA Astrophysics Data System (ADS)

observations from a space-borne radiometer and a ground-based precipitation profiling radar, the impact of cloud microphysics schemes in the WRF model on the simulation of microwave brightness temperature (Tb), radar reflectivity, and Doppler velocity (Vdop) is studied for a winter storm in California. The unique assumptions of particles size distributions, number concentrations, shapes, and fall speeds in different microphysics schemes are implemented into a satellite simulator and customized calculations for the radar are performed to ensure consistent representation of precipitation properties between the microphysics schemes and the radiative transfer models.Simulations with four different schemes in the WRF model, including the Goddard scheme (GSFC), the WRF single-moment 6-class scheme (WSM6), the Thompson scheme (THOM), and the Morrison double-moment scheme (MORR), are compared directly with measurements from the sensors. Results show large variations in the simulated radiative properties. General biases of ~20 K or larger are found in (polarization-corrected) Tb, which is linked to an overestimate of the precipitating ice aloft. The simulated reflectivity with THOM appears to agree well with the observations, while high biases of ~5-10 dBZ are found in GSFC, WSM6 and MORR. Peak reflectivity in MORR exceeds other schemes. These biases are attributable to the snow intercept parameters or the snow number concentrations. Simulated Vdop values based on GSFC agree with the observations well, while other schemes appear to have a ~1 m s-1 high bias in the ice layer. In the rain layer, the model representations of Doppler velocity vary at different sites.

Han, Mei; Braun, Scott A.; Matsui, Toshihisa; Williams, Christopher R.

2013-02-01

159

The Solid Rocket Motor Slag Population: Results of a Radar-Based Regressive Statistical Evaluation  

NASA Astrophysics Data System (ADS)

Solid rocket motor (SRM) slag has been identified as a potential source of man-made orbital debris. The possibility that SRMs (in addition to generating dust particles in the sub-millimeter range) may generate particles up to centimeters in size has caused concern regarding their contribution to the debris environment. Returned surfaces from space do not have sufficient area or exposure time to provide a clear picture of the SRM millimeter and centimeter debris population. Currently, radar observation is probably the only way to collect data showing the debris contribution from SRMs. Such observation is used to sample the debris environment, but it is difficult to obtain accurate orbital elements for the detected debris objects. NASA has developed several models to describe the different orbital debris populations, based on assumed debris production mechanisms to create clouds of debris objects that can be propagated in time. The NASA model, LEGEND (LEO-to-GEO Environment Debris), functions as a timetested debris model for most debris sources. However, the current LEGEND model does not include contributions from the SRM population. An SRM model has recently been developed by NASA, based on purely theoretical details of SRM production and known SRM launches, but verification with hard data is needed. Because the detections of individual SRM objects cannot be deterministically separated from the total debris observed by radar, the validation of the SRM model can only be done by combining it with the LEGEND breakup model and comparing it with data. By applying observational constraints, the degree of SRM slag contribution to the environment may be estimated. This serves as an observationally sound method from which to calibrate a purely theoretical model into something more realistic. For this study, we use the populations observed by the Haystack radar from 1996 to present. For the SRM debris, we use a historical database of SRM launches, propellant masses, and estimated locations and times of tail-off to produce and propagate the SRM debris clouds. Comparisons with radar data from the ensuing years were made, and the SRM model was altered with respect to size and mass production of slag particles to reflect the populations estimated from the data. The result is a model SRM population that fits within the bounds of the observed environment and estimates of the production and contribution of SRM debris to the environment.

Horstman, Matthew

160

Development of radar and lidar simulator and its application to the evaluation of the cloud and aerosol microphysics in the AGCM  

NASA Astrophysics Data System (ADS)

The radar and lidar simulator is presented for the evaluation of the cloud and aerosol microphysical properties reproduced in the models such as the AGCM and the NHM. There are two possible ways to evaluate the macro-scale and microphysical properties of clouds and aerosols simulated in the models; one is the comparison of the simulated microphysics with the retrieved ones by the algorithms. The other is the direct comparisons of the observed and simulated radar and lidar signals. The simulator is designed to use the outputs about the cloud and aerosol microphysical properties from the models to simulate the observables obtained by the radar and the lidar. It can treat ice and water clouds as well as aerosols. Particle shapes and orientations of ice particles are also taken into account in the estimation of the backscattering and extinction properties of ice clouds in the radar and lidar wavelengths. Four aerosol types are also considered; sulfate, carbonaceous, sea-salt and dust particles, in the lidar simulations. The simulator has a function to generate both of the ground-based and space-borne radar and lidar signals from the output parameters. It is worth to note that the same cloud and aerosol particle models and their scattering properties are also used in the retrieval algorithms for cloud and aerosol microphysics from the space-borne or ground-based radar and lidar observations. This consistency assures the further investigation of the information content obtained in the comparisons of observed and simulated signals. Some application of the radar and lidar simulator is demonstrated for the comparison of the shipborne measurements and the AGCM. We also present the comparisons of the radar reflectivity observed in CloudSat and the lidar backscattering coefficients at 532nm and 1064nm and depolarization ratio in CALIPSO with the simulated signals in the GCM. Extension of the simulator for the EarthCARE CPR and ATLID lidar is also introduced. Information content in the comparisons of the observed and simulated signals is discussed together with the analysis of the comparisons of retrieved and simulated microphysics of clouds and aerosols. The essential parts of the radar and lidar simulator have been incorporated into the Joint Simulator for Satellite Sensors(J-simulator).

Okamoto, H.; Sato, K.; Takemura, T.; Hagihara, Y.; Nishizawa, T.

2011-12-01

161

Combining Meteorological Stations and Satellite data to Evaluate the Offshore Wind Power Resource of Southeastern Brazil  

NASA Astrophysics Data System (ADS)

Wind is strong and steady over the ocean, but on-site marine meteorological data are sparse. Here we draw on meteorological station, satellite data (QuikSCAT), and both theoretical and practical measures of wind turbine performance. The meteorological stations give high time resolution direct measurements at a few points and provide validation and adjustment of the satellite data. The satellite data provide near-complete area coverage at lower time resolution. For the southern coast of Brazil, we use both data sets to evaluate the location, timing, and availability of the resource. Then, using bathymetry and the properties of current wind-electric technology, we develop maps of wind speed, wind power density, and practical turbine output in power units (GW). In the shallower waters of south Brazil, along only one coastal area situated between 28°S and 33°S we find a total resource of 102 GW average electrical production. The potential electrical output of this one coastal region based on current technology is near today's average electric demand for the country.

Pimenta, F. M.; Kempton, W.; Garvine, R. W.

2007-12-01

162

Doppler Radar  

Microsoft Academic Search

This paper contains a discussion of the principle of operation of cw doppler search radar systems and an analysis of their performance capabilities, with particular emphasis on the elimination of fixed targets. A comparison of these systems and MTI pulse radar systems is made.

E. J. Barlow

1949-01-01

163

TRMM Radar.  

National Technical Information Service (NTIS)

The results of a conceptual design study and the performance of key components of the Bread Board Model (BBM) of the Tropical Rainfall Measuring Mission (TRMM) radar are presented. The radar, which operates at 13.8 GHz and is designed to meet TRMM mission...

K. Okamoto

1993-01-01

164

Harm effect distances evaluation of severe accidents for gaseous hydrogen refueling station  

Microsoft Academic Search

With the development of large-scale fell cell vehicle demonstration project worldwide, the global number of hydrogen refueling stations has increased rapidly in recent years. The external safety of hydrogen refueling stations has always been a public concern for its further development. This paper examines the harm effect distances of severe accidents for a gaseous hydrogen refueling station. First, different accident

Li Zhiyong; Pan Xiangmin; Ma Jianxin

2010-01-01

165

Evaluation of the CAI (Computer Assisted Instruction) Segments of the Tow Field Test Set and the Hawk CW (Continuous Wave) Radar Repair Courses.  

National Technical Information Service (NTIS)

The objective of this study was to conduct an evaluation of the computer assisted instruction (CAI) segments of the TOW Field Test Set (TFTS) Course and the HAWK Continuous Wave Radar Repair Course conducted at MMC/S. Computer Assisted Instruction for bot...

G. W. Levy L. D. Francis L. G. Welling

1983-01-01

166

Improvement of radar quantitative precipitation estimation based on real-time adjustments to Z-R relationships and inverse distance weighting correction schemes  

NASA Astrophysics Data System (ADS)

The errors in radar quantitative precipitation estimations consist not only of systematic biases caused by random noises but also spatially nonuniform biases in radar rainfall at individual rain-gauge stations. In this study, a real-time adjustment to the radar reflectivity-rainfall rates ( Z-R) relationship scheme and the gauge-corrected, radar-based, estimation scheme with inverse distance weighting interpolation was developed. Based on the characteristics of the two schemes, the two-step correction technique of radar quantitative precipitation estimation is proposed. To minimize the errors between radar quantitative precipitation estimations and rain gauge observations, a real-time adjustment to the Z-R relationship scheme is used to remove systematic bias on the time-domain. The gauge-corrected, radar-based, estimation scheme is then used to eliminate non-uniform errors in space. Based on radar data and rain gauge observations near the Huaihe River, the two-step correction technique was evaluated using two heavy-precipitation events. The results show that the proposed scheme improved not only in the underestimation of rainfall but also reduced the root-mean-square error and the mean relative error of radar-rain gauge pairs.

Wang, Gaili; Liu, Liping; Ding, Yuanyuan

2012-05-01

167

Mode S Baseline Radar Tracking.  

National Technical Information Service (NTIS)

Tests and evaluation were conducted to determine the baseline performance characteristics of the Moving Target Detector (MTD) and Radar Data Acquisition System (RDAS) as an integral part of the Mode S sensor. The MTD and RDAS were separately evaluated to ...

E. F. Mancus L. H. Baker

1982-01-01

168

Microwave Emissions from Police Radar  

Microsoft Academic Search

This study evaluated police officers' exposures to microwaves emitted by traffic radar units. Exposure measurements were taken at approximated ocular and testicular levels of officers seated in patrol vehicles. Comparisons were made of the radar manufacturers' published maximum power density specifications and actual measured power densities taken at the antenna faces of those units. Four speed-enforcement agencies and one transportation

J. M. Fink; J. P. Wagner; J. J. Congleton; J. C. Rock

1999-01-01

169

A scan converter radar display system  

Microsoft Academic Search

A radar display system, designed to integrate on a single display target information from several radars, has been designed and evaluated. Integration is obtained through the use of single gun scan converter tubes. The resultant image on the TV monitor is a bright steady PPI image which is updated at the end of each radar scan. Limitations imposed on the

N. V. Oneal; P. M. Thiebaud

1975-01-01

170

Evaluation of the hydrologic measure quality of the Saint Nizier weather radar data on the local urban area of Greater Lyon  

NASA Astrophysics Data System (ADS)

The meteorological radar of Saint Nizier d'Azergues, part of Meteo France network Aramis, is situated at only 40 km from the urban community of Greater Lyon, in the north of the Rhône valley, south-east of France. This area gathers many human, environmental and materials stakes and vulnerability. From an operational use, an assessment based on a simulation and analysis of real data has identified certain sectors of the community affected by problems of ground clutter, which have to be filtered before any furthermore hydrologic use. There is a very good consistency between the two types of analysis. This agreement helps to confirm the cause and extent of sources of error in the real images. These confirm the areas within the urban area affected by the phenomena of ground clutter. The list of these pixels considered less reliable, has been compiled and they were screened to very locally compare the radar values to the values of rainfall in the urban community of Lyon. Indeed, Lyon has a network of measuring the rain in urban areas among the densest in Europe, totaling about fifty rainfall stations of various organizations on its territory, which creates a density of about one rain gauge for sixteen km². In this study, only raingauges properties of the Urban Community of Lyon were used: 29 tipping bucket devices currently in operation, providing data each 6 minutes. The average rain radar on the town were calculated for the sample of 17 rain episodes from the period 2001 - 2005, and compared to average from 29 rain gauges Grand Lyon. The differences between radar estimations and rainfall values show high amplitude over time, especially in winter. Thus, a factor based on raingauges was assigned to radar data in order to match the average values and radar rainfall for each rain events. These radar adjusted data were then compared to each punctual rainfall values associated (each raingauge value has been compared to a radar pixel value associated thanks to a vertical extraction). The comparison of surface and punctual radar data to the values of the dense network of rain gauges in the community showed a small difference between these measurement values after the use of a spatial uniform weighting ratio, and filtering pixels of lower quality. Specifically, the average difference between radar data and rainfall values around 20% episodes all together, but drops to nearly 10% during exceptionally abundant or long term time rainy episodes potentially harmful. To provide complete coverage of data on the study territory, especially on ground clutter zones filtered, two spatialization techniques were used. The results of the cross validation have shown the usefulness of ordinary kriging compared to cokriging, which is a lot more complicated to use and not really better in this precise study case.

Renard, F.; Faure, D.; Comby, J.

2009-04-01

171

An intercomparison of radar-based liquid cloud microphysics retrievals and implications for model evaluation studies  

NASA Astrophysics Data System (ADS)

This paper presents a statistical comparison of three cloud retrieval products of the Atmospheric Radiation Measurement (ARM) program at the Southern Great Plains (SGP) site from 1998 to 2006: MICROBASE, University of Utah (UU), and University of North Dakota (UND) products. The probability density functions of the various cloud liquid water content (LWC) retrievals appear to be consistent with each other. While the mean MICROBASE and UU cloud LWC retrievals agree well in the middle of cloud, the discrepancy increases to about 0.03 gm-3 at cloud top and cloud base. Alarmingly large differences are found in the droplet effective radius (re) retrievals. The mean MICROBASE re is more than 6 ?m lower than the UU re, whereas the discrepancy is reduced to within 1 ?m if columns containing raining and/or mixed-phase layers are excluded from the comparison. A suite of stratified comparisons and retrieval experiments reveal that the LWC difference stems primarily from rain contamination, partitioning of total liquid later path (LWP) into warm and supercooled liquid, and the input cloud mask and LWP. The large discrepancy among the re retrievals is mainly due to rain contamination and the presence of mixed-phase layers. Since rain or ice particles are likely to dominate radar backscattering over cloud droplets, the large discrepancy found in this paper can be thought of as a physical limitation of single-frequency radar approaches. It is therefore suggested that data users should use the retrievals with caution when rain and/or mixed-phase layers are present in the column.

Huang, D.; Zhao, C.; Dunn, M.; Dong, X.; Mace, G. G.; Jensen, M. P.; Xie, S.; Liu, Y.

2012-06-01

172

Follow-on Operational Test and Evaluation Phase II (FOTE II) Narrowband High Frequency Evaluation Report for Offutt Giant Talk Station.  

National Technical Information Service (NTIS)

The 1815th Test and Evaluation Squadron performed a Follow-on Operational Test and Evaluation, Phase II, of the Scope Signal III equipment at Offutt Giant Talk Station. Originator-supplied key words include: Follow-on Operational Test and Evaluation, Phas...

P. J. Gaudreault

1985-01-01

173

Technical evaluation of the adequacy of station electric-distribution-system voltages for the Arkansas Nuclear One, Unit 2  

SciTech Connect

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the Arkansas Nuclear One, Unit 2. The evaluation is to determine if the onsite distribution system in conjunction with the offsite power sources has sufficient capacity to automatically start and operate all Class 1E loads within the equipment voltage ratings under certain conditions established by the Nuclear Regulatory Commission. The analyses submitted demonstrate that the station's electric distribution system supplies adequate voltage to the Class 1E equipment under the worst case conditions analyzed.

Selan, J.C.

1982-03-10

174

Technical evaluation of the adequacy of station electric distribution system voltages for the Arkansas Nuclear One, Unit 1  

SciTech Connect

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the Arkansas Nuclear One, Unit 1. The evaluation is to determine if the onsite distribution system in conjunction with the offsite power sources has sufficient capacity to automatically start and operate all Class 1E loads within the equipment voltage ratings under certain conditions established by the Nuclear Regulatory Commission. The analyses submitted demonstrate that the station's electric distribution system supplies adequate voltage to the Class 1E equipment under the worst case conditions analyzed.

Selan, J.C.

1981-12-16

175

Automatic Evaluation of Progression Angle and Fetal Head Station through Intrapartum Echographic Monitoring  

PubMed Central

Labor progression is routinely assessed through transvaginal digital inspections, meaning that the clinical decisions taken during the most delicate phase of pregnancy are subjective and scarcely supported by technological devices. In response to such inadequacies, we combined intrapartum echographic acquisitions with advanced tracking algorithms in a new method for noninvasive, quantitative, and automatic monitoring of labor. Aim of this work is the preliminary clinical validation and accuracy evaluation of our automatic algorithm in assessing progression angle (PA) and fetal head station (FHS). A cohort of 10 parturients underwent conventional labor management, with additional translabial echographic examinations after each uterine contraction. PA and FHS were evaluated by our automatic algorithm on the acquired images. Additionally, an experienced clinical sonographer, blinded regarding the algorithm results, quantified on the same acquisitions of the two parameters through manual contouring, which were considered as the standard reference in the evaluation of automatic algorithm and routine method accuracies. The automatic algorithm (mean error ± 2SD) provided a global accuracy of 0.9 ± 4.0?mm for FHS and 4° ± 9° for PA, which is far above the diagnostic ability shown by the routine method, and therefore it resulted in a reliable method for earlier identification of abnormal labor patterns in support of clinical decisions.

Casciaro, Ernesto; Di Renzo, Gian Carlo; Perrone, Antonio

2013-01-01

176

47 CFR 87.107 - Station identification.  

Code of Federal Regulations, 2012 CFR

...also be identified by the location of its control point. (c) Survival craft station...exempted from the use of a call sign: Airborne weather radar, radio altimeter, air traffic control transponder, distance measuring...

2012-10-01

177

47 CFR 87.107 - Station identification.  

Code of Federal Regulations, 2011 CFR

...also be identified by the location of its control point. (c) Survival craft station...exempted from the use of a call sign: Airborne weather radar, radio altimeter, air traffic control transponder, distance measuring...

2011-10-01

178

Evaluation of the attenuation provided by a radar absorbing material (RAM) coating on an HF wire rope antenna  

Microsoft Academic Search

A shipboard electromagnetic interference (EMI) problem is considered. The use of radar absorbent material (RAM) to reduce unintentional X-band (8-12 GHz) radar reflections from HF wire rope antennas is analyzed. An exact series solution for a lossy-coated circular cylinder was developed and used to determine the effectiveness of the various RAM coatings

Griffin K. Gothard; Broun Hall

1991-01-01

179

A reflectivity climatology algorithm for hybrid scans and its application to radar coverage over the Tibetan Plateau  

NASA Astrophysics Data System (ADS)

The traditional algorithm for hybrid radar scans uses standard terrain digital elevation model (DEM) data and the latitudes, longitudes and altitudes of contributing radar stations. While radar station location information is often inaccurate, signal blockages due to trees, buildings, and other surface objects are not included in the DEM data. Accordingly, hybrid scan elevations derived using this traditional algorithm are prone to errors. Here, reflectivity climatology data (the frequency of occurrence of reflectivity) are used to improve the algorithm for hybrid scans. Three parameters are introduced, then applied to evaluation of signal blockage for every radar bin using a fuzzy logic technique. This new algorithm provides an improved determination of the lowest unblocked elevation for hybrid scans. The new algorithm is validated by examining the scope and continuity of the calculated hybrid scan reflectivity in a case study, and the performance of this climatology-based algorithm is evaluated relative to the traditional terrain-based algorithm. The climatology-based hybrid scans are then used to examine the spatial coverage provided by the operational weather radar network over the Tibetan Plateau. The results indicate that the terrain-based hybrid scan algorithm introduced errors that caused obvious V-shaped gaps in hybrid scan reflectivity. By contrast, the climatology-based hybrid scan algorithm more accurately determined the lowest unblocked elevation and reduced the impacts of blockage. The coverage map illustrates the limitations of the weather radar network over the Tibetan Plateau. These limitations inhibit the usefulness of the radar data. Additional radar or observational data are needed to fill these gaps and minimize the impacts of signal blockage.

Zhuang, Wei; Liu, Liping

2012-12-01

180

Health Hazard Evaluation Report HHE 73-000-023, Cincinnati Gas and Electric Miami Ft. Station, Cincinnati, Ohio.  

National Technical Information Service (NTIS)

An evaluation of asbestos exposure was conducted at the Cincinnati Gas and Electric Miami Fort Station on March 21, 1973. Four personal examples were taken on workers who were removing insulation from a boiler. The analysis of the four samples taken was c...

R. A. Mertz

1973-01-01

181

Threat radar system simulations  

NASA Astrophysics Data System (ADS)

The capabilities, requirements, and goals of radar emitter simulators are discussed. Simulators are used to evaluate competing receiver designs, to quantify the performance envelope of a radar system, and to model the characteristics of a transmitted signal waveform. A database of candidate threat systems is developed and, in concert with intelligence data on a given weapons system, permits upgrading simulators to new projected threat capabilities. Four currently available simulation techniques are summarized, noting the usefulness of developing modular software for fast controlled-cost upgrades of simulation capabilities.

Miller, L.

182

Quantitative evaluation of closed-cycle Ocean Thermal Energy Conversion (OTEC) technology in central station applications  

SciTech Connect

The results of an independent quantitative evaluation by Rand of Ocean Thermal Energy Conversion (OTEC) for central station applications are summarized. The methodology developed and implemented for the quantitative analysis of cost sensitivities and engineering uncertainties provides the Office of Energy Research (OER) with the capability for evaluating the effects of alternative OTEC R and D strategies. The analysis also provides a general quantitative approach to assess advanced energy technologies. This study focuses on closed-cycle OTEC for delivery of electric power to the United States. Performance and costs of complete commercial OTEC systems are analyzed at the system level using inputs from component analyses and thermal-resource data for sites in the Gulf of Mexico. Such sites could feed the Gulf Coast from the west coast of Florida to the New Orleans areas. In this evaluation, the energy conversion analysis, i.e., the study of the power system, is based on a thermodynamic analysis of the complete system, which includes allowances for losses in all circuits. A cost-minimization scheme is used to ensure that the cycle component choices are near optimal. To make these cost-minimization calculations, cost algorithms are developed for the principal components. Off-design operations are of great importance in the Gulf of Mexico because of significant seasonal surface temperature variations and the quite large resulting variations of output power. These effects are accounted for in this study by calculating the off-design performance of the power systems and by selecting the cycle that maximizes the average power over the year. Capital cost estimates are made for the complete system. (WHK)

Gritton, E.C.; Pei, R.Y.; Aroesty, J.; Balaban, M.M.; Gazley, C.; Hess, R.W.; Krase, W.H.

1980-05-01

183

Laser Radar Development.  

National Technical Information Service (NTIS)

A range-gated imaging (RGI) laser radar system was constructed and field-tested at the Chesapeake Bay Division of the Naval Research Laboratories to evaluate the capability of RGI systems to provide extremely high contrast image displays. The system emplo...

J. A. Jenney

1968-01-01

184

Terminal doppler weather radar (TDWR) build 5B operational test and evaluation (OT&E) integration and OT&E operational test plan  

Microsoft Academic Search

The Terminal Doppler Weather Radar (TDWR) Build 5B Enhancement Operational Test and Evaluation (OT&E) Integration and OT&E Operational Test Plan provides the overall philosophy and approach to Build 5B OT&E testing, and identifies OT&E objectives, responsibilities, and resources. The TDWR Build 5B Enhancement provides connectivity to the Low Level Wind Shear Alert System (LLWAS) III to display LLWAS III data

Radame Martinez; Steven Viveiros; Donne Wedge; Peter Guthlein

1995-01-01

185

Evaluation of Low Earth Orbit Environmental Effects on International Space Station Thermal Control Materials.  

National Technical Information Service (NTIS)

Samples of International Space Station (ISS) thermal control coatings were exposed to simulated low Earth orbit (LEO) environmental conditions to determine effects on optical properties. In one test, samples of the white paint coating Z-93P were coated wi...

C. K. Reed J. A. Dever M. M. Hasegawa S. K. Rutledge

1998-01-01

186

Technical evaluation study: Energy-recovery solid waste incineration to Naval Station, Mayport, Florida  

Microsoft Academic Search

This study was undertaken to assess the feasibility of energy-recovery incineration of solid waste at Naval Station Mayport, Florida. It was found that use of solid waste as a fuel for steam generation at Naval Station Mayport is technically and economically feasible and environmentally compatible. The recommended system employs a clean-fuel fired, basket-grate incinerator in series with an energy-recovery train

S. A. Hathaway; H. G. Rigo

1975-01-01

187

Technical evaluation study: energy-recovery solid waste incineration to Naval Station Mayport, Florida. Technical report  

Microsoft Academic Search

This study was undertaken to assess the feasibility of energy-recovery incineration of solid waste at Naval Station Mayport, Florida. It was found that use of solid waste as a fuel for steam generation at Naval Station Mayport is technically and economically feasible and environmentally compatible. The recommended system employs a clean-fuel fired, basket-grate incinerator in series with an energy-recovery train

S. A. Hathaway; H. G. Rigo

1975-01-01

188

Evaluation of precipitation chemistry siting criteria using paired stations from northern Maine and southeastern Texas  

SciTech Connect

During the early 1970's, the Environmental Protection Agency (EPA) and the National Oceanic and Atmospheric Administration (NOAA) began precipitation chemistry monitoring at ten National Weather Service (NWS) stations located across the United States. The goal was to design a network consisting of regionally representative precipitation stations to define the levels and gradients of concentration of the chemicals found in precipitation. The data were also useful for effects research and, over a period of decades, for the calculation of trends. A monthly wet-only sampling protocol was used and EPA analyzed the samples for pH, SO{sub 4}{sup =}, NO{sub 3}{sup -}, Cl{sup -}, Na{sup +}, NH{sub 4}{sup +}, Mg{sup ++}, K{sup +}, Ca{sup ++}, conductivity and precipitation depth. In an effort to test the representativeness of two of the sites, Victoria, and Caribou, colocated stations were established at Beeville, Texas and Presque Isle, Maine according to NADP protocol. Two-year data records are currently available for both of these new sites. It is the purpose of this paper to compare the data from the paired stations to determine whether or not the precipitation chemistry from the original stations is different from the new stations.

Artz, R.S.; Rolph, G.D. (National Oceanic and Atmospheric Administration, Silver Spring, MD (USA))

1987-01-01

189

Design of a Digital Simulation of the Polar Planimeter for Calculating Areas of Echoes from Radar Weather Observations.  

National Technical Information Service (NTIS)

The effort discussed in the report was to fulfill a requirement for expediently analyzing data on radar weather prediction techniques. Data is recorded at various radar stations, which make hourly weather observations on the local weather activity within ...

R. G. Kelley

1968-01-01

190

Evaluation of postglacial rebound models combining GRACE, InSAR, regional atmospheric climate modeling and radar altimetry data  

NASA Astrophysics Data System (ADS)

Large uncertainties remain in the determination of the glacial isostatic adjustment (GIA) signal in Antarctica. Here we use GRACE measurements of time variable gravity, InSAR measurements of ice motion, IceBridge measurements of ice thickness, surface mass balance from RACMO regional atmospheric climate model and radar altimetry measurements of change in ice surface elevation to evaluate and compare several GIA models such as IJ05, ICE5G etc. We compare the spatial patterns in ice mass change from these independent techniques to identify discrepancies caused by errors in the modeled GIA signal. We find that a thinner ice sheet at the last glacial maximum may be required in East Antarctica as well as in the Ross Sea drainage area. In the Bellingshausen Sea area the comparison indicate that a larger GIA signal, probably generated by a combination of lower viscosity structure and ice mass loss within the last 500 years, is required. We present improved regional GIA correction based on those constraints. We also quantify how this improves the agreement among the different mass balance techniques.

Sutterley, T. C.; Velicogna, I.; Ivins, E. R.; Rignot, E. J.; van den Broeke, M. R.

2011-12-01

191

Technical Evaluation Report on the Monitoring of Electric Power to the Reactor Protection System for the Millstone Nuclear Power Station, Unit 1 (Docket No. 50-245).  

National Technical Information Service (NTIS)

This report documents the technical evaluation of the monitoring of electric power to the reactor protection system (RPS) at the Millstone Nuclear Power Station, Unit 1. The evaluation is to determine if the proposed design modification will protect the R...

J. C. Selan

1984-01-01

192

Technical Evaluation Report on the Monitoring of Electric Power to the Reactor Protection System for the Vermont Yankee Nuclear Power Station (Docket No. 50-271).  

National Technical Information Service (NTIS)

This report documents the technical evaluation of the monitoring of electric power to the reactor protection system (RPS) at the Vermont Yankee Nuclear Power Station. The evaluation is to determine if the proposed design modification will protect the RPS ...

J. C. Selan

1984-01-01

193

Shuttle radar topography mission accuracy assessment and evaluation for hydrologic modeling  

NASA Astrophysics Data System (ADS)

Digital Elevation Models (DEMs) are increasingly used even in low relief landscapes for multiple mapping applications and modeling approaches such as surface hydrology, flood risk mapping, agricultural suitability, and generation of topographic attributes. The National Aeronautics and Space Administration (NASA) has produced a nearly global database of highly accurate elevation data, the Shuttle Radar Topography Mission (SRTM) DEM. The main goals of this thesis were to investigate quality issues of SRTM, provide measures of vertical accuracy with emphasis on low relief areas, and to analyze the performance for the generation of physical boundaries and streams for watershed modeling and characterization. The absolute and relative accuracy of the two SRTM resolutions, at 1 and 3 arc-seconds, were investigated to generate information that can be used as a reference in areas with similar characteristics in other regions of the world. The absolute accuracy was obtained from accurate point estimates using the best available federal geodetic network in Indiana. The SRTM root mean square error for this area of the Midwest US surpassed data specifications. It was on the order of 2 meters for the 1 arc-second resolution in flat areas of the Midwest US. Estimates of error were smaller for the global coverage 3 arc-second data with very similar results obtained in the flat plains in Argentina. In addition to calculating the vertical accuracy, the impacts of physiography and terrain attributes, like slope, on the error magnitude were studied. The assessment also included analysis of the effects of land cover on vertical accuracy. Measures of local variability were described to identify the adjacency effects produced by surface features in the SRTM DEM, like forests and manmade features near the geodetic point. Spatial relationships among the bare-earth National Elevation Data and SRTM were also analyzed to assess the relative accuracy that was 2.33 meters in terms of the total standard deviation for flat areas of central Indiana with a positive bias for SRTM relative to the national elevation dataset. Physical watershed boundaries, streams vector files and topographic attributes have been produced to investigate the SRTM global coverage performance in watershed modeling applications. The verification of the precision of hydrologic delineations in Indiana with the availability of Hydrologic Units datasets at watershed and subwatershed levels showed very small differences in drainage areas calculated, even at subwatershed levels. The hydrologic boundaries and drainage network extraction for the Arrecifes basin in the Argentine Pampas was checked for quality assurance with Landsat data and georeferenced digital topographic quadrangles, demonstrating the feasibility of using the SRTM global coverage for water resources mapping. SRTM data presents unique challenges, but the results of this research have shown that high quality results can be obtained. However, there are numerous issues related to preprocessing of SRTM data for certain surface hydrology applications to be addressed regarding SRTM in such as watershed characterization, land use planning, hazards assessment, energy resources assessment and many other uses around the world.

Mercuri, Pablo Alberto

194

Radar Antenna.  

National Technical Information Service (NTIS)

An antenna is described for range-gated, pulse doppler, radar systems. The antenna includes first and second, shortened, half-wave dipoles and first and second reflecting screens. One dipole is fed through a fixed 22 1/2 degree phase-shift network while t...

O. E. Rittenback

1978-01-01

195

Construction and precision evaluation of the GPS virtual reference station network in North Taiwan  

NASA Astrophysics Data System (ADS)

The conventional single-reference station positioning is affected by systematic errors such as ionospheric and tropospheric delay, so that the rover must be located within 10 km from the reference station in order to acquire centimeter-level accuracy. The medium-range real-time kinematic has been proven feasible and can be used for high precision applications. However, the longer of the baseline, the more of the time for resolving the integer ambiguity. This is due to the fact that systematic errors can't be eliminated effectively by double- differencing. Recently, network approaches have been proposed to overcome the limitation of the single- reference station positioning. The real-time systematic error modeling can be achieved with the use of GPS network. For expanding the effective range and decreasing the density of the reference stations, Land Survey Bureau, Ministry of the Interior in Taiwan have set up a national GPS network. In order to obtain the high precision positioning and provide the multi-goals services, a GPS network including 27 stations already been constructed in North Taiwan. The users can download the corrections from the data center via the wireless internet and obtain the centimeter-level accuracy positioning. The service is very useful for surveyors and the high precision coordinates can be obtained real time.

Yeh, T.; Lee, Z.; Chang, M.; Chen, C.

2006-12-01

196

3D cloud reconstructions: Evaluation of scanning radar scan strategy with a view to surface shortwave radiation closure  

NASA Astrophysics Data System (ADS)

ability of six scanning cloud radar scan strategies to reconstruct cumulus cloud fields for radiation study is assessed. Utilizing snapshots of clean and polluted cloud fields from large eddy simulations, an analysis is undertaken of error in both the liquid water path and monochromatic downwelling surface irradiance at 870 nm of the reconstructed cloud fields. Error introduced by radar sensitivity, choice of radar scan strategy, retrieval of liquid water content (LWC), and reconstruction scheme is explored. Given an infinitely sensitive radar and perfect LWC retrieval, domain average surface irradiance biases are typically less than 3 W m-2 µm-1, corresponding to 5-10% of the cloud radiative effect (CRE). However, when using a realistic radar sensitivity of -37.5 dBZ at 1 km, optically thin areas and edges of clouds are difficult to detect due to their low radar reflectivity; in clean conditions, overestimates are of order 10 W m-2 µm-1 (~20% of the CRE), but in polluted conditions, where the droplets are smaller, this increases to 10-26 W m-2 µm-1 (~40-100% of the CRE). Drizzle drops are also problematic; if treated as cloud droplets, reconstructions are poor, leading to large underestimates of 20-46 W m-2 µm-1 in domain average surface irradiance (~40-80% of the CRE). Nevertheless, a synergistic retrieval approach combining the detailed cloud structure obtained from scanning radar with the droplet-size information and location of cloud base gained from other instruments would potentially make accurate solar radiative transfer calculations in broken cloud possible for the first time.

Fielding, Mark D.; Chiu, J. Christine; Hogan, Robin J.; Feingold, Graham

2013-08-01

197

Forecasting weather radar propagation conditions  

NASA Astrophysics Data System (ADS)

The increasing use of weather radar quantitative precipitation estimates, particularly in automatic applications such as operational hydrometeorological modelling or assimilation in numerical weather prediction (NWP) models, has promoted the development of quality control procedures on radar data. Anomalous propagation (AP) of the radar beam due to deviation from the standard refractivity vertical profile, is one of the factors that may affect seriously the quality of radar observations because of the increase in quantity and intensity of non-precipitating clutter echoes and consequent contamination of the estimated rainfall field. Another undesired effect of AP is the change in the expected radar echo height, which may be relevant when correcting for beam blockage in radar rainfall estimation in complex terrain. The aim of this paper is to study the use of NWP mesoscale forecasts to predict and monitor AP events. A nested 15-km grid resolution version of the MASS model has been used to retrieve refractivity profiles in the coastal area of Barcelona, near a weather radar and a radiosonde station. Using the refractivity profiles two different magnitudes were computed: the vertical refractivity profile of the lowest 1000 m layer and a ducting index which describes the existence and intensity of the most super-refractive layer contained in the lowest 3-km layer. A comparison between model forecasts and radiosonde diagnostics during a six-month period showed that the model tended to underestimate the degree of super-refraction, with a bias of 4 km-1 and RMSE of 11 km-1 in the 1-km vertical refractivity gradient. Further analysis of the data showed that a combination of previous observations and forecasts allowed to produce modified forecasts improving the original direct model output, decreasing substantially the bias, reducing the RMSE by 20% and improving the skill by 40%, beating also radiosonde observations persistence.

Bech, J.; Codina, B.; Lorente, J.

2007-06-01

198

Ho' oponopono: A Radar Calibration CubeSat.  

National Technical Information Service (NTIS)

To accurately identify and track objects over its territories, the US military must regularly monitor and calibrate its 80+ C-band radar tracking stations distributed around the world. Unfortunately, only two calibration satellites are currently in servic...

J. G. Furumo L. K. Martin N. G. Fisher W. A. Shiroma W. H. Jones

2011-01-01

199

23. SITE BUILDING 002 SCANNER BUILDING RADAR CONTROL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

23. SITE BUILDING 002 - SCANNER BUILDING - RADAR CONTROL INTERFACE "RCL NO. 2" WITH COMPUTER CONTROL DISC DRIVE UNITS IN FOREGROUND. - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

200

Limited Characterization of the SPADS Radar System, Project 'START'.  

National Technical Information Service (NTIS)

The USAF Test Pilot School conducted flight tests to characterize the Weibel-manufactured Spaceport Arrival and Departure System (SPADS) radar functionality and performance for potential use as a single-station time-space- position information (TSPI) sour...

K. M. Roessig L. C. Kearl O. Carazo F. Ferreri

2005-01-01

201

22. SITE BUILDING 002 SCANNER BUILDING RADAR CONTROL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. SITE BUILDING 002 - SCANNER BUILDING - RADAR CONTROL ROOM. RECEIVER EQUIPMENT ON RIGHT WITH RF RADIATION MONITOR CABINET. - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

202

XOQDOQ: computer program for the meteorological evaluation of routine effluent releases at nuclear power stations. Final report  

Microsoft Academic Search

Provided is a user's guide for the US Nuclear Regulatory Commission's (NRC) computer program X0QDOQ which implements Regulatory Guide 1.111. This NUREG supercedes NUREG-0324 which was published as a draft in September 1977. This program is used by the NRC meteorology staff in their independent meteorological evaluation of routine or anticipated intermittent releases at nuclear power stations. It operates in

J. F. Sagendorf; J. T. Goll; W. F. Sandusky

1982-01-01

203

The near real time terminal for VLBI radar method  

Microsoft Academic Search

Combination of radar and VLBI allowed obtaining the new scientific instrument for measurement of short-periodic variation of planet proper rotation and determination of the Solar system body orbits in the radio reference frame. Radar, spectral lines, low frequency, spacecraft navigation observations could benefit from this inexpensive solution in those stations where large antennas and sensitive receivers are available and where

A. E. Volvach; G. Tuccari; I. E. Molotov; I. D. Strepka

2005-01-01

204

Aircraft target measurements using A GSM-based passive radar  

Microsoft Academic Search

Passive radar using GSM cellular mobile communication signal had been demonstrated to be feasible for short-range moving target measurements. This paper presents some new results of aircraft measurements with enhanced performance. It is shown that the operation range of GSM-based passive radar can be substantially larger than the coverage of one normal base station cell that is allocated for mobile

Hongbo Sun; D. K. P. Tan; Yilong Lu

2008-01-01

205

50. View of waveguides beginning to move toward two radar ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

50. View of waveguides beginning to move toward two radar scanner switches (two per radar scanner building) by vertical bends; also tuning devices are located here. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

206

9. View southeast corner of perimeter acquisition radar power plant ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. View southeast corner of perimeter acquisition radar power plant room #214, control room; showing central monitoring station console in foreground. Well and booster control panel in left background and electric power management panel on far right - Stanley R. Mickelsen Safeguard Complex, Perimeter Acquisition Radar Power Plant, In Limited Access Area, Southwest of PARB at end of Service Road B, Nekoma, Cavalier County, ND

207

9. View toward northeast, southwest oblique of perimeter acquisition radar ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. View toward northeast, southwest oblique of perimeter acquisition radar building showing, from left to right, fuel oil pump station, cooling towers, power plant, and diesel intake/exhaust - Stanley R. Mickelsen Safeguard Complex, Perimeter Acquisition Radar Building, Limited Access Area, between Limited Access Patrol Road & Service Road A, Nekoma, Cavalier County, ND

208

Sea and air moving target measurements using a GSM based passive radar  

Microsoft Academic Search

A passive radar is essentially a receiver-only radar that does not transmit signals; it only receives and thus operates independently without the direct synchronization from the non-cooperative illuminator. GSM base station transmitter as the illuminator of opportunity in a passive radar offers a covert means of uninterrupted surveillance where the major advantage is that the emitters of such transmissions are

Danny K. P. Tan; Hongbo Sun; Yilong Lu

2005-01-01

209

Bats Avoid Radar Installations: Could Electromagnetic Fields Deter Bats from Colliding with Wind Turbines?  

Microsoft Academic Search

Large numbers of bats are killed by collisions with wind turbines, and there is at present no direct method of reducing or preventing this mortality. We therefore determine whether the electromagnetic radiation associated with radar installations can elicit an aversive behavioural response in foraging bats. Four civil air traffic control (ATC) radar stations, three military ATC radars and three weather

Barry Nicholls; Paul A. Racey

2007-01-01

210

Flood Monitoring using X-band Dual-polarization Radar Network  

NASA Astrophysics Data System (ADS)

A dense weather radar network is an emerging concept advanced by the Center for Collaborative Adaptive Sensing of the Atmosphere (CASA). Using multiple radars observing over a common will create different data outcomes depending on the characteristics of the radar units employed and the network topology. To define this a general framework is developed to describe the radar network space, and formulations are obtained that can be used for weather radar network characterization. Current weather radar surveillance networks are based upon conventional sensing paradigm of widely-separated, standalone sensing systems using long range radars that operate at wavelengths in 5-10 cm range. Such configuration has limited capability to observe close to the surface of the earth because of the earth's curvature but also has poorer resolution at far ranges. The dense network radar system, observes and measures weather phenomenon such as rainfall and severe weather close to the ground at higher spatial and temporal resolution compared to the current paradigm. In addition the dense network paradigm also is easily adaptable to complex terrain. Flooding is one of the most common natural hazards in the world. Especially, excessive development decreases the response time of urban watersheds and complex terrain to rainfall and increases the chance of localized flooding events over a small spatial domain. Successful monitoring of urban floods requires high spatiotemporal resolution, accurate precipitation estimation because of the rapid flood response as well as the complex hydrologic and hydraulic characteristics in an urban environment. This paper reviews various aspects in radar rainfall mapping in urban coverage using dense X-band dual-polarization radar networks. By reducing the maximum range and operating at X-band, one can ensure good azimuthal resolution with a small-size antenna and keep the radar beam closer to the ground. The networked topology helps to achieve satisfactory sensitivity and fast temporal update across the coverage. Strong clutter is expected from buildings in the neighborhood which act as perfect reflectors. The reduction in radar size enables flexible deployment, such as rooftop installation, with small infrastructure requirement, which is critical in a metropolitan region. Dual-polarization based technologies can be implemented for real-time mitigation of rain attenuations and accurate estimation of rainfall. The NSF Engineering Research Center for Collaborative Adaptive Sensing of the Atmosphere (CASA) is developing the technologies and the systems for network centric weather observation. The Differential propagation phase (Kdp) has higher sensitivity at X-band compared to S and C band. It is attractive to use Kdp to derive Quantitative Precipitation Estimation (QPE) because it is immune to rain attenuation, calibration biases, partial beam blockage, and hail contamination. Despite the advantage of Kdp for radar QPE, the estimation of Kdp itself is a challenge as the range derivative of the differential propagation phase profiles. An adaptive Kdp algorithm was implemented in the CASA IP1 testbed that substantially reduces the fluctuation in light rain and the bias at heavy rain. The Kdp estimation also benefits from the higher resolution in the IP1 radar network. The performance of the IP1 QPE product was evaluated for all major rain events against the USDA Agriculture Research Service's gauge network (MicroNet) in the Little Washita watershed, which comprises 20 weather stations in the center of the test bed. The cross-comparison with gauge measurements shows excellent agreement for the storm events during the Spring Experiments of 2007 and 2008. The hourly rainfall estimates compared to the gauge measurements have a very small bias of few percent and a normalized standard error of 21%. The IP1 testbed was designed with overlapping coverage among its radar nodes. The study area is covered by multiple radars and the aspect of network composition is also evaluated. The independence of Kdp on the radar calibration e

Chandrasekar, V.; Wang, Y.; Maki, M.; Nakane, K.

2009-09-01

211

Using radar charts with qualitative evaluationTechniques to assess change in blended learning  

Microsoft Academic Search

When university academics implement changes in learning, such as introducing blended learning, it is conventional practice to examine and evaluate the impact of the resulting curriculum reform. Judging the worth and impact of an educational development is a complex task involving subtle differences in learning. Qualitative methods to explore these deep processes in learning include using interviews, observations and open-ended

Dan Kaczynski; Leigh Wood; Ansie Harding

2008-01-01

212

STARE: A new radar auroral backscatter experiment in northern Scandinavia  

Microsoft Academic Search

As part of the ground-based program for the International Magnetospheric Study (IMS), a new two-station VHF radar auroral experiment, STARE, has been constructed in northern Scandinavia. Each of these stations can provide good spatial and temporal resolution measurements of the intensity and Doppler velocity of radar auroral irregularities within a 300,000 km 2 scattering region. Approximately 230,000 km 2 of

R. A. Greenwald; W. Weiss; E. Nielsen; N. R. Thomson

1978-01-01

213

Human Factors Evaluation of the Robotic Interface for Space Station Freedom Orbital Replaceable Units.  

National Technical Information Service (NTIS)

An orbital replaceable unit (ORU) is often defined as any orbital unit aboard Space Station with a wearout life of less than 30 years. The capability of successful changeout of these units by remote manipulation is critical to the ORU to telerobot interfa...

C. E. Sampaio E. Y. Hwang T. F. Fleming M. A. Stuart A. J. Legendre

1992-01-01

214

Evaluating local anthropogenic impact on remote Arctic monitoring stations: a case study at Summit, Greenland  

Microsoft Academic Search

Summit, Greenland is a remote Arctic research station allowing for field measurements at the highest point of the Greenland Ice Sheet. Due to the current reliance on diesel generators for electricity at Summit, unavoidable local emissions are a potential contamination threat to the measurement of combustion-related species in the air and snow. The effect of fossil-fuel combustion on particulate elemental

G. S. W. Hagler; M. H. Bergin; E. A. Smith; M. Town; J. E. Dibb

2008-01-01

215

Using radar and lidar instrument simulators to evaluate moist processes in the Community Atmosphere Model  

Microsoft Academic Search

Global vertically-profiling active satellite observations and instrument simulator packages enable new exposure of moist processes in global climate models. We evaluate the representation of cloud and precipitation processes within two versions of NCAR's Community Atmosphere Model (CAM) that will be used for IPCC integrations (CAM3.5, CAM4). The two CAM model versions have large differences in cloud water content, cloud particle

J. E. Kay; A. Gettelman; Y. Zhang; G. L. Stephens

2009-01-01

216

Technical evaluation of the adequacy of station electric-distribution-system voltages for the Duane Arnold Energy Center  

SciTech Connect

The technical evaluation of the adequacy of the station electric distribution system voltages for the Duane Arnold Energy Center is documented. The evaluation is to determine if the onsite distribution system in conjunction with the offsite power sources has sufficient capacity to automatically start and operate all Class 1E loads within the equipment voltage ratings under certain conditions established by the Nuclear Regulatory Commission. The analyses submitted demonstrate that the offsite power sources in conjunction with the onsite distribution system has sufficient capacity and capability to supply adequate voltages to the Class 1E equipment under worst case conditions.

Selan, J.C.

1981-10-12

217

Technical evaluation of the adequacy of station electric distribution system voltages for the Haddam Neck Nuclear Power Plant  

SciTech Connect

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the Haddam Neck Nuclear Power Plant. The evaluation is to determine if the onsite distribution system, in conjunction with the offsite power sources, has sufficient capacity to automatically start and operate all class 1E loads within the equipment voltage ratings under certain conditions established by the Nuclear Regulatory Commission. The analysis shows that the electric distribution system has the capacity and capability to supply adequate voltage to the class 1E equipment, provided that the grid is maintained at or above the administrative minimum limits.

Selan, J.C.

1982-02-01

218

Technical evaluation of the monitoring of electric power to the reactor protection system for the Cooper Nuclear Station  

SciTech Connect

This report documents the technical evaluation of the monitoring of electric power to the reactor protection system (RPS) at the Cooper Nuclear Station. The evaluation is to determine if the proposed design modification will protect the RPS from abnormal voltage and frequency conditions which could be supplied from the power supplies and will meet certain requirements set forth by the Nuclear Regulatory Commission. The proposed design modifications with time delays verified by GE, will protect the RPS from sustained abnormal voltage and frequency conditions from the supplying sources.

Selan, J.C.

1982-03-02

219

Characterization of ocean surface current properties from single site HF/VHF radar  

NASA Astrophysics Data System (ADS)

Surface current mapping from HF/VHF coastal radars traditionally requires at least two distant sites. Vector velocities are estimated by combining the radial velocity components measured by the radars. In many circumstances (e.g., failures, interferences, logistics constraints), such a combination is not possible by lack of data from one station. Two methods are evaluated to get information on surface circulation from a single site radar: the Vectorial Reconstruction Method (VRM) for current vector mapping and the Vortex Identification Method (VIM) for detecting eddy-like structures. The VRM assumes a non-divergent horizontal surface current, and the VIM analyzes radial velocities and their radial and orthoradial gradients. These two methods are tested on modeled and measured data sets in the Northwestern Mediterranean Sea where both high-resolution ocean circulation model and radar campaigns are available. The VRM performance is strongly limited by the divergence-free hypothesis which was not satisfied in our real data. The VIM succeeded in detection of vortex in the Gulf of Lions and from an operating single site radar located on the Provence coasts in summer.

Marmain, Julien; Forget, Philippe; Molcard, Anne

2011-11-01

220

Using radar and lidar instrument simulators to evaluate moist processes in the Community Atmosphere Model  

NASA Astrophysics Data System (ADS)

Global vertically-profiling active satellite observations and instrument simulator packages enable new exposure of moist processes in global climate models. We evaluate the representation of cloud and precipitation processes within two versions of NCAR’s Community Atmosphere Model (CAM) that will be used for IPCC integrations (CAM3.5, CAM4). The two CAM model versions have large differences in cloud water content, cloud particle size, tropospheric humidity, and precipitation frequency and intensity. CloudSat and CALIOP observations and the COSP simulator package are used to produce “apple-to-apple” comparisons between observed and modeled cloud and precipitation properties. We then assess the fidelity of CAM3.5 and CAM4 cloud and precipitation fields to the CloudSat and CALIOP observations in three areas of climatological interest: the Pacific stratocumulus regions, the Tropical Pacific warm pool, and the North Pacific mid-latitude storm track. In addition to observational comparison, the climate implications of the revealed inter-model and observational differences will be discussed.

Kay, J. E.; Gettelman, A.; Zhang, Y.; Stephens, G. L.

2009-12-01

221

Evaluating the thermodynamic efficiency of hydrogen cycles at wet-steam nuclear power stations  

NASA Astrophysics Data System (ADS)

Various schematic solutions for implementing a hydrogen cycle on the basis of thermal and nuclear power stations are discussed. Different approaches to construction of cooling systems for the combustion chambers used in hydrogen-oxygen steam generators are described. An example of solution is given in which the combustion chamber is cooled by steam, which is the most efficient one in the thermodynamic respect. Results from an assessment of the thermodynamic efficiency of hydrogen cycles organized on the basis of the power unit of a wet-steam nuclear power station equipped with a K-1000-60/1500 turbine are presented. The thermodynamic efficiency of different schematic and parametric versions of implementing a hydrogen cycle, including those with a satellite turbine operating on displaced steam, is carried out. It is shown that the use of satellite turbines allows the power output and efficiency of the power unit of a wet-steam nuclear power station to be upgraded in a reliable and effective manner.

Aminov, R. Z.; Egorov, A. N.

2013-04-01

222

Safety Evaluation Report: Related to the License Renewal of Kewaunee Power Station, Docket No. 50-305, Dominion Energy Kewaunee, Inc.  

National Technical Information Service (NTIS)

This safety evaluation report (SER) documents the technical review of the Kewaunee Power Station (KPS) license renewal application (LRA) by the U.S. Nuclear Regulatory Commission (NRC) staff (the staff). By letter dated August 12, 2008, Dominion Energy Ke...

2011-01-01

223

Southeast oblique (southeast to northwest) of controlled area sentry station/visitor ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Southeast oblique (southeast to northwest) of controlled area sentry station/visitor center - Stanley R. Mickelsen Safeguard Complex, Controlled Area Sentry Station, On Access Road at entrance to Perimeter Acquisition Radar Site, Nekoma, Cavalier County, ND

224

Operational evaluation of 5 cm Doppler radar. Two contributions: Review of WSR-74C Doppler radar operations at WSO Montgomery, Alabama (April 1982 - August 1983). The Johnson-Effect resolving ambiguous Doppler velocities  

Microsoft Academic Search

The National Weather Service (NWS) office in Montgomery, Alabama has been interested in new radar technology for several years and a working relationship with Enterprise Electronics Corp. (EEC) has provided their office with a look at some of the newer advances in meteorological radar equipment. In April, 1982, a request was made by Enterprise Electronics Corp. to the NWS for

P. E. Pettit; W. N. Johnson

1984-01-01

225

Adjusting weather radar data to rain gauge measurements with data-driven models  

NASA Astrophysics Data System (ADS)

Weather radar networks provide data with good spatial coverage and temporal resolution. Hence they are able to describe the variability of precipitation. Typical radar stations determine the rain rate for every square kilometre and make a full volume scan within about 5 minutes. A weakness however, is their often poor metering precision limiting the applicability of the radar for hydrological purposes. In contrast to rain gauges, which measure precipitation directly on the ground, the radar determines the reflectivity aloft and remote. Due to this principle, several sources of possible errors occur. Therefore improving the radar estimates of rainfall is still a vital topic in radar meteorology and hydrology. This paper presents data-driven approaches to improve radar estimates of rainfall by mapping radar reflectivity measurements Z to rain gauge data R. The analysis encompasses several input configurations and data-driven models. Reflectivity measurements at a constant altitude and the vertical profiles of reflectivity above a rain gauge are used as input parameters. The applied models are Artificial Neural Network (ANN), Model Tree (MT), and IBk a k-nearest-neighbour classifier. The relationship found between the data of a rain gauge and the reflectivity measurements is subsequently applied to another site with comparable terrain. Based on this independent dataset the performance of the data-driven models in the various input configurations is evaluated. For this study, rain gauge and radar data from the province of Styria, Austria, were available. The data sets extend over a two-year period (2001 and 2002). The available rain gauges use the tipping bucket principle with a resolution of 0.1 mm. Reflectivity measurements are obtained from the Doppler weather radar station on Mt. Zirbitzkogel (by courtesy of AustroControl GmbH). The designated radar is a high-resolution C-band weather-radar situated at an altitude of 2372 m above mean sea level. The data-driven models exhibit different performances on the various input configurations. Also data transformations were applied. The logarithm recommends itself for this transformation because the original Z-R-relationship is a power function, and the logarithm linearises this non-linear relationship. The MT which is a piecewise linear model performs best on logarithmised data. The IBk works well when transforming the reflectivity data in rain rate first. Overall the ANN exhibits the best performance showing a 10 % improvement in correlation and RMSE compared to the standard Z-R-relationship. When applying the vertical profile of reflectivity as input parameter, the correlation exhibits a more than 30 % improvement. The results indicate that the vertical profile of reflectivity provided by weather radars yields not only information on the type of precipitation, whether it is stratiform or convective. In data-driven models the vertical profile of reflectivity can help to get better estimates of rain rates on the ground, even in mountainous terrain without low-altitude radar measurements.

Teschl, Reinhard; Randeu, Walter; Teschl, Franz

2010-05-01

226

Safety Evaluation of the Byron Station, Units 1 and 2, and the Braidwood Station, Units 1 and 2. Docket Nos. STN 50-454, STN 50-455, STN 50-456, STN 50-457.  

National Technical Information Service (NTIS)

A safety evaluation of the Commonwealth Edison Company's application for licenses to construct and operate its proposed Byron Station, Units 1 and 2 (Docket Nos. STN-50-454 and STN-50-455), located in Rockvale Township, Ogle County, Illinois, and its prop...

1975-01-01

227

Advanced Forward Area Tactical Radar Network.  

National Technical Information Service (NTIS)

An advanced tactical radar network which is under conceptual development by the Air Force, with an anticipated installation date in the late 1980s, is described and some of the primary design choices are evaluated. The proposed radar network would provide...

J. D. Spragins

1977-01-01

228

Adaptive Multipath Cancellation Algorithm in Passive Radar  

Microsoft Academic Search

In passive radar system, multipath components including direct wave heavily degrades the performance of target detecting. This paper is focused on adaptive multipath cancellation algorithm in passive radar. In order to evaluate the level of cancellation required, the self-ambiguity of FM is analyzed, and the necessary minimum ratio of interference suppressed is brought forward. According to the similarity of multipath

Kui Wang; Ran Tao; Yongfeng Ma; Tao Shan

2006-01-01

229

Radar data processing. Volume 2 - Advanced topics and applications  

Microsoft Academic Search

The design and implementation of the radar data processing (RDP) theory are discussed. Data processing for netted monostatic and bistatic radar systems and technical problems such as the misalignment between radars and target altitude uncertainty are examined. The organization and display of the data on a computer system are studied. The computer simulation of tracking algorithms for RDP performance evaluation

A. Farina; F. A. Studer

1986-01-01

230

Multiparameter Radar Observations of Time Evolution of Convective Storms: Evaluation of Water Budgets and Latent Heating Rates  

Microsoft Academic Search

One advantage of dual-polarization radars is the ability to differentiate between water and ice phases in storms. The application of difference reflectivity ( ZDP) in the analysis of mixed-phase precipitation is presented. Here, ZDP analysis is used to obtain the fraction of water and ice in mixed-phase precipitation. The techniques developed are applied to data collected on 9 August 1991

Hui Tong; V. Chandrasekar; K. R. Knupp; James Stalker

1998-01-01

231

Hard threshold correlation detector for mobile HF Surface Wave Radar  

Microsoft Academic Search

Mobile HF Surface Wave Radar (SWR) can be realized by an offshore distributed receiver array structure which communicates to the central processing unit at the base station via a wireless link. State of the art detectors demand a sophisticated signal processing which can only be done at base station hence making it imperative to transmit raw data form receiver to

Anshu Gupta; Th. Fickenscher

2012-01-01

232

Radar Ionospheric Impact Mitigation  

Microsoft Academic Search

New ionospheric modeling technology is being developed to improve correction of ionospheric impacts on the performance of ground-based space-surveillance radars (SSRs) in near-real-time. These radars, which detect and track space objects, can experience significant target location errors due to ionospheric delay and refraction of the radar signals. Since these radars must detect and track targets essentially to the radar horizon,

G. Bishop; D. Decker; C. Baker

2006-01-01

233

Radar clutter classification  

NASA Astrophysics Data System (ADS)

The problem of classifying radar clutter as found on air traffic control radar systems is studied. An algorithm based on Bayes decision theory and the parametric maximum a posteriori probability classifier is developed to perform this classification automatically. This classifier employs a quadratic discriminant function and is optimum for feature vectors that are distributed according to the multivariate normal density. Separable clutter classes are most likely to arise from the analysis of the Doppler spectrum. Specifically, a feature set based on the complex reflection coefficients of the lattice prediction error filter is proposed. The classifier is tested using data recorded from L-band air traffic control radars. The Doppler spectra of these data are examined; the properties of the feature set computed using these data are studied in terms of both the marginal and multivariate statistics. Several strategies involving different numbers of features, class assignments, and data set pretesting according to Doppler frequency and signal to noise ratio were evaluated before settling on a workable algorithm. Final results are presented in terms of experimental misclassification rates and simulated and classified plane position indicator displays.

Stehwien, Wolfgang

1989-11-01

234

Performance and evaluation of gas-engine-driven split-system cooling equipment at the Willow Grove Naval Air Station  

SciTech Connect

DOE`s Federal Energy Management Program supports efforts to reduce energy use and associated expenditures within the federal sector; one such effort, the New Technology Demonstration Program (NTDP)(formerly the Test Bed Demonstration program), seeks to evaluate new energy saving US technologies and secure their more timely adoption by the federal government. This report describes the field evaluation conducted to examine the performance of a 15-ton natural-gas-engine- driven, split-system, air-conditioning unit. The unit was installed at a multiple-use building at Willow Grove Naval Air Station, a regular and reserve training facility north of Philadelphia, and its performance was monitored under the NTDP.

Armstrong, P.R.; Schmelzer, J.R.

1997-01-01

235

Multiparameter radar analysis using wavelets  

NASA Astrophysics Data System (ADS)

Multiparameter radars have been used in the interpretation of many meteorological phenomena. Rainfall estimates can be obtained from multiparameter radar measurements. Studying and analyzing spatial variability of different rainfall algorithms, namely R(ZH), the algorithm based on reflectivity, R(ZH, ZDR), the algorithm based on reflectivity and differential reflectivity, R(KDP), the algorithm based on specific differential phase, and R(KDP, Z DR), the algorithm based on specific differential phase and differential reflectivity, are important for radar applications. The data used in this research were collected using CSU-CHILL, CP-2, and S-POL radars. In this research multiple objectives are addressed using wavelet analysis namely, (1)space time variability of various rainfall algorithms, (2)separation of convective and stratiform storms based on reflectivity measurements, (3)and detection of features such as bright bands. The bright band is a multiscale edge detection problem. In this research, the technique of multiscale edge detection is applied on the radar data collected using CP-2 radar on August 23, 1991 to detect the melting layer. In the analysis of space/time variability of rainfall algorithms, wavelet variance introduces an idea about the statistics of the radar field. In addition, multiresolution analysis of different rainfall estimates based on four algorithms, namely R(ZH), R( ZH, ZDR), R(K DP), and R(KDP, Z DR), are analyzed. The flood data of July 29, 1997 collected by CSU-CHILL radar were used for this analysis. Another set of S-POL radar data collected on May 2, 1997 at Wichita, Kansas were used as well. At each level of approximation, the detail and the approximation components are analyzed. Based on this analysis, the rainfall algorithms can be judged. From this analysis, an important result was obtained. The Z-R algorithms that are widely used do not show the full spatial variability of rainfall. In addition another intuitively obvious result was observed namely, R( KDP) has reduced the spatial variability due to smoothing of KDP estimates. The convective and stratiform separation was studied using multiresolution analysis. The June 22, 1995 data collected by CSU-CHILL radar were used to evaluate the technique. Another set of data collected on August 23, 1991 representing stratiform conditions were also studied.

Tawfik, Ben Bella Sayed

236

Effects of propagation conditions on radar beam-ground interaction: impact on data quality  

Microsoft Academic Search

A large part of the research in the radar meteorology is devoted to the evaluation of the radar data quality and to the radar data processing. Even when, a set of absolute quality indexes can be produced (like as ground clutter presence, beam blockage rate, distance from radar, etc.), the final product quality has to be determined as a function

A. Fornasiero; P. P. Alberoni; R. Amorati; L. Ferraris; A. C. Taramasso

2005-01-01

237

Engineering evaluation of magma cooling-tower demonstration at Nevada Power Company's Sunrise Station. Final report  

SciTech Connect

The Magma Cooling Tower (MCT) process utilizes a falling film heat exchanger integrated into an induced draft cooling tower to evaporate wastewater. A hot water source such as return cooling water (90/sup 0/F to 110/sup 0/F) provides the energy for evaporation. Water quality control is maintained by removing potential scaling constituents to make concentration of the wastewater possible without scaling heat transfer surfaces. A pilot-scale demonstration test of the MCT process was performed from March 1979 through June 1979 at Nevada Power Company's Sunrise Station in Las Vegas, Nevada. The pilot unit extracted heat from the powerplant cooling system to evaporate cooling tower blowdown. Two water quality control methods were employed: makeup/sidestream softening and fluidized bed crystallization. The 11-week softening mode test was successful. The unit operated without biofouling or scaling at 100,000 ppM TDS levels under a wide range of operating conditions. Successful operation was not demonstrated in the 10-day crystallization mode test; calcium sulfate (CaSO/sub 4/) scaling occurred on the last day of the test at a maximum brine concentration of less than 40,000 ppM. An economic and technical comparison with other zero-discharge technologies showed that, for application at Sunrise, the MCT process had competitive capital, operating, and levelized annual costs. No major technical problems were encountered that would preclude the commercial application of a properly designed MCT unit operating in the softening mode.

Not Available

1980-11-01

238

Evaluation of two AN/APS-94 side-looking airborne radar systems in the detection of search and rescue targets  

NASA Astrophysics Data System (ADS)

Side-looking airborne radar (SLAR) detection data were gathered in conjunction with four visual detection experiments designed to improve search planning guidance contained in the National Search and Rescue Manual. HC-130 aircraft, equipped with either the Airborne Oil Surveillance System (AOSS) or SLAR/radar image processor (SLAR/RIP) configuration of the AN/APS-94C or D SLAR, conducted controlled searches for life rafts, small boats, and 41- to 95-foot Coast Guard vessels in Block Island Sound or open ocean. Using a microwave tracking system and SLAR data, the positions of searchers and targets were accurately reconstructed to facilitate the verification of detections on SLAR films or video tape. These data were used to evaluate the effects of environmental and controllable parameters on SLAR detection of the various target types. Target size/composition search altitude, swell height, wind speed, and humidity/precipitation were found to have a significant influence of SLAR detection performance. Upper-bound lateral range curves and sweep widths for SLAR search are included. Real-time performance tests for AN/APS-94D SLAR and system performance tests for new SLARs (AN/APS-131) are recommended.

Osmer, S. R.; Edwards, N. C., Jr.; Hover, G. L.; Mazour, T. J.

1981-08-01

239

Polarization radar processing technology  

NASA Astrophysics Data System (ADS)

A comprehensive effort is presented involving measurements and performance evaluation for the detection of scatters immersed in a background of natural and man-made clutter using polarization diverse waveforms. The effort spans evaluation from the initial stages of theoretical formulation to processor performance evaluation using real world data. The theoretical approach consists of determining polarimetric statistical properties of the backscatter waveform and the use of these properties to derive the optimum dual polarized S-Band radar system with selectable polarization on both transmit and receive. Recording equipment consists of 12 bit digital in-phase and quadrature channels indexed in time and phase for both polarizations. Several processors utilizing optimum and sub-optimum algorithms were evaluated using simulated and live radar data, and performance results were compared. The processor types include fully adaptive algorithms designed to operate on polarimetric spectral spread waveforms, and several combinations of single channel and polarization diverse receivers with both single and dual transmit polarization. A conventional fixed transmit and receive mode with no spectral processing is included. Comparisons are made between the various processors. The simulated and real data consist of randomly scattered dipoles, spheres, Swerling type scatters, and scatters of opportunity.

Stiefvater, Kenneth C.; Brown, Russell D.; Vannicola, Vincent C.; Wicks, Michael C.

1989-10-01

240

A Suburban Femtocell Model for Evaluating Signal Quality Improvement in WiMAX Networks with Femtocell Base Stations  

Microsoft Academic Search

The femtocell base station is a low power and low cost small base station in the customer premise. It connects to the core network via cable, DSL or similar backhaul technology. In this paper, we focus on how received signal quality can be improved by deploying femtocell base stations in a WiMAX system. We propose a suburban femtocell model to

Pei-Chen Lu; Kang-Ju Tsao; Cheng-Ru Huang; Ting-Chao Hou

2010-01-01

241

Global radar units on Venus derived from statistical analysis of Pioneer Venus Orbiter radar data  

NASA Astrophysics Data System (ADS)

The classification of surface radar units on Venus using an unsupervised cluster analysis of Pioneer Venus radar reflectivity and root-mean-square (rms)-slope data is described. The advantages of the unsupervised analysis are discussed. F tests are utilized to evaluate the numerical significance of the clusters. The derived rms-slope data and reflectivity for 15 radar units are presented. The relations between radar data bases and elevation are studied. The lowlands, rolling plains, highlands, and mountainous surface of Venus are examined. The geology of Venus landing sites and radar properties, and the surface radar reflectivity images and earth-based images are compared. The spatial relations between classification units are calculated. It is concluded that the unsupervised analysis data correlate well with Head et al. (1985b) data and produce more detailed classification images.

Davis, P. A.; Kozak, R. C.; Schaber, G. G.

1986-04-01

242

Technical evaluation report on the proposed design modifications and technical specification changes on grid voltage degradation for the Millstone Nuclear Power Station, Unit 1  

Microsoft Academic Search

This report documents the technical evaluation of the proposed design modifications and Technical Specification change for protection of Class 1E equipment from grid voltage degradation for the Millstone Nuclear Power Station, Unit 1. The review criteria are based on several IEEE standards and the Code of Federal Regulations. The evaluation finds that the licensee has not provided sufficient information on

Selan

1982-01-01

243

Technical evaluation report on the proposed design modifications and technical-specification changes on grid voltage degradation for the San Onofre Nuclear Genetating Station, Unit 1  

Microsoft Academic Search

This report documents the technical evaluation of the proposed design modifications and Technical Specification changes for protection of Class 1E equipment from grid voltage degradation for the San Onofre Nuclear Generating Station, Unit 1. The review criteria are based on several IEEE standards and the Code of Federal Regulations. The evaluation finds that the proposed design modifications and Technical Specification

Selan

1982-01-01

244

Evaluation of geophysical logs, Phase I, at Willow Grove Naval Air Station, Montgomery County, Pennsylvania  

USGS Publications Warehouse

Between April and June 1997, the U.S. Navy contracted Brown and Root Environmental, Inc., to drill 20 monitor wells at the Willow Grove Naval Air Station in Horsham Township, Montgomery County, Pa. The wells were installed to monitor water levels and allow collection of water samples from shallow, intermediate, and deep water-bearing zones. Analysis of the samples will determine the horizontal and vertical distribution of any contaminated ground water migrating from known contaminant sources. Eight wells were drilled near the Fire Training Area (Site 5), five wells near the 9th Street Landfill (Site 3), four wells at the Antenna Field Landfill (Site 2), and three wells near Privet Road Compound (Site 1). Depths range from 73 to 167 feet below land surface. The U.S. Geological Survey conducted borehole-geophysical and borehole-video logging to identify water-bearing zones so that appropriate intervals could be screened in each monitor well. Geophysical logs were run on the 20 monitor wells and 1 existing well. Video logs were run on 16 wells. Caliper and video logs were used to locate fractures, inflections on fluid-temperature and fluid-resistivity logs were used to locate possible water-bearing fractures, and flowmeter measurements verified these locations. Single-point-resistance and natural-gamma logs provided information on stratigraphy. After interpretation of geophysical logs, video logs, and driller's notes, all wells were screened such that water-level fluctuations could be monitored and discrete water samples collected from one or more shallow and intermediate water-bearing zones in each borehole.

Conger, R. W.

1997-01-01

245

An evaluation of the IRI-2007 storm time model at low latitude stations  

NASA Astrophysics Data System (ADS)

This paper discusses the ability of the International Reference Ionosphere IRI-2007 storm time model to predict foF2 ionospheric parameter during geomagnetic storm periods. Experimental data (based on availability) from two low latitude stations: Vanimo (geographic coordinates, 2.7 °S, 141.3 °E, magnetic coordinates, 12.3 °S, 212.50 °E) and Darwin (geographic coordinates, 12.45 °S, 130.95 °E, magnetic coordinates, 22.9 °S, 202.7 °E) during nine storms that occurred in 2000 (Rz12 = 119), 2001(Rz12 = 111) and 2003 (Rz12 = 64) are compared with those obtained by the IRI-2007 storm model. The results obtained show that the percentage deviation between the experimental and IRI predicted foF2 values during these storm periods is as high as 100% during the main and recovery phases. Based on the values of "relative deviation module mean" (RDMM) obtained (i.e. between 0.08 and 0.60), it is observed that there is a reasonable to poor agreement between measured foF2 values and the IRI-storm model prediction values during main and recovery phases of the storms under investigation. As a result, in addition to other studies that have been carried out from different sectors, more studies are required to be carried out. This will enable IRI community to improve on the present performance of the model. In general the IRI-storm model predictions follow normal trend of the foF2 measured values but does not reproduce well the measured values.

Oyeyemi, E. O.; Adewale, A. O.; Adeloye, A. B.; Olugbon, B.

2013-11-01

246

Features of ultrawideband radar projecting  

Microsoft Academic Search

The article presents a new approach to ultrawideband (UWB) radar projecting. Some advantages of such radars are shown in comparison with common narrowband radars and some features of UWB radars are considered, which do not allow the use of traditional methods. New methods of UWB radar characteristics calculation and radar systems projecting are suggested. It discusses the range equation, passive

Igor Immoreev; B. Vovshin

1995-01-01

247

XOQDOQ: computer program for the meteorological evaluation of routine effluent releases at nuclear power stations. Final report  

SciTech Connect

Provided is a user's guide for the US Nuclear Regulatory Commission's (NRC) computer program X0QDOQ which implements Regulatory Guide 1.111. This NUREG supercedes NUREG-0324 which was published as a draft in September 1977. This program is used by the NRC meteorology staff in their independent meteorological evaluation of routine or anticipated intermittent releases at nuclear power stations. It operates in a batch input mode and has various options a user may select. Relative atmospheric dispersion and deposition factors are computed for 22 specific distances out to 50 miles from the site for each directional sector. From these results, values for 10 distance segments are computed. The user may also select other locations for which atmospheric dispersion deposition factors are computed. Program features, including required input data and output results, are described. A program listing and test case data input and resulting output are provided.

Sagendorf, J.F.; Goll, J.T.; Sandusky, W.F.

1982-09-01

248

Pulse Doppler radar simulation study  

Microsoft Academic Search

In the past several years two different models have been produced for predicting detection performance of space-based and airborne coherent pulsed radars. The present work describes enhancements incorporated in the software including: (1) conversion of the code to ANSI standard FORTRAN-77; (2) development and implementation of a suitable algorithm for the evaluation of the clutter covariance matrix of an array

Murray Gibb; Leonard Lightstone; Ronald H. Saper

1988-01-01

249

Station Models  

NSDL National Science Digital Library

This project will allow users to become acquainted with station models that are found on weather maps. Students will study the various atmospheric variables that are depicted on a station model and then practice on an interactive station model program. Part 1 - Being able to read and interpret weather maps is a very important skill in meteorology. One of the most basic skills of predicting the weather is being able to interpret a station model of a given location. A station model is a bundle of information that ...

Ertl, Mr.

2007-11-03

250

Evaluation of the prompt alerting systems at four nuclear power stations  

SciTech Connect

This report presents evaluations of the prompt notification siren systems at the following four US nuclear power facilities: Trojan, Three Mile Island, Indian Point, and Zion. The objective of these evaluations was to provide examples of an analytical procedure for predicting siren-system effectiveness under specific conditions in the 10-mile emergency planning zone (EPZ) surrounding nuclear power plants. This analytical procedure is discussed in report No. PNL-4227.

Towers, D.A.; Anderson, G.S.; Keast, D.N.; Kenoyer, J.L.; Desrosiers, A.E.

1982-09-01

251

Estimation of rainfall field by combining radar data and raingauge observations: the modified conditional merging technique  

NASA Astrophysics Data System (ADS)

The estimation of rainfall fields, especially its spatial distribution and position is a crucial task both for rainfall nowcasting and for modeling catchment response to rainfall. Some studies of literature about multisensor datafusion prove that combining data from raingauges and radar represents the best way to obtain an enhanced ad more reliable estimation of QPE and of the associated river discharge. Sinclair and Peagram (2004) have proposed the Conditional Merging (CM) technique, a merging algorithm which extract the information content from the observed data and use it within an interpolation method to obtain the rainfall maps. The raingauges provide a punctual measure of the ground-observed rainfall while the remote sensors (radar network or satellite constellation) supply rainfall estimation maps which give an idea of the correlation and structure of covariance of the observed field. In this work is presented an algorithm called Modified Conditional Merging that is based on CM and which is used for real-time estimation of the optimal rainfall maps. The area of interest is Italy, where are both available a dense network of raingauge measurements (about 2000 stations) and a QPE estimated by the Italian Radar composite. The main innovation respect to classical CM is to estimate the structure of covariance and the length of spatial correlation ?, for every raingauge, directly from the cumulated radar rainfall fields. An application to several test cases together with the evaluation of algorithm performances are presented and discussed.

Pignone, F.; Rebora, N.; Silvestro, F.

2012-04-01

252

A new method for combining radar and raingauge data: Modified Conditional Merging  

NASA Astrophysics Data System (ADS)

The estimation of rainfall fields, especially its spatial distribution and position is a crucial task both for rainfall nowcasting and for modeling catchment response to rainfall. Some studies of literature about multisensor have suggested that discharge estimations are improved when radar and rain gauge data are combined to estimate input rainfall fields.Sinclair and Peagram (2004) have proposed the Conditional Merging (CM) technique, a merging algorithm which extract the information content from the observed data and use it within an interpolation method to obtain the rainfall maps. The idea is to combine the "real", but punctual amount of rainfall measured by raingauges with the structure of covariance and correlation of rainfall maps estimated from remote sensors (radar network or satellite constellation). In this work is studied an enhanced algorithm based on CM, called Modified Conditional Merging.. The main innovation respect to classical CM is the estimation of the structure of covariance and the length of spatial correlation ?, for every raingauge, directly from the cumulated radar rainfall fields. The domain of application is the Italy, where are both available a dense network of raingauge measurements (about 2500 stations) and a QPE estimated by the Italian Radar composite. The MCM algorithm can be used in real-time over the whole domain to produce hourly the optimal rainfall maps. An application to several test cases together with the evaluation of algorithm performances are presented and discussed.

Pignone, Flavio; Rebora, Nicola; Silvestro, Francesco

2013-04-01

253

Vector quantization and learning vector quantization for radar target classification  

NASA Astrophysics Data System (ADS)

Radar target classification performance is greatly dependent on how the classifier represents the strongly angle dependent radar target signatures. This paper compares the performance of classifiers that represent radar target signatures using vector quantization (VQ) and learning vector quantization (LVQ). The classifier performance is evaluated with a set of high resolution millimeter-wave radar data from four ground vehicles (Camaro, van, pickup, and bulldozer). LVQ explicitly includes classification performance in its data representation criterion, whereas VQ only makes use of a distortion measure such as mean square distance. The classifier that uses LVQ to represent the radar data has a much higher probability of correct classification than VQ.

Stewart, Clayton V.; Lu, Yi-Chuan; Larson, Victor J.

1993-10-01

254

Goldstone Solar System Radar.  

National Technical Information Service (NTIS)

Planning, direction, experimental design, and coordination of data-acquisition and engineering activities in support of all Goldstone planetary radar astronomy were performed. This work demands familiarity with the various components of a planetary radar ...

R. F. Jurgens

1988-01-01

255

Radar Absorbing Material Design.  

National Technical Information Service (NTIS)

Low observable platforms have extremely low radar cross section specifications that cannot be achieved by shaping alone. The application of radar absorbing material is necessary, in which case the appropriate constitutive parameters and thickness must be ...

C. K. Yuzcelik

2003-01-01

256

Radar, Target and Ranging.  

National Technical Information Service (NTIS)

This Test Operations Procedure (TOP) provides conventional test methods employing conventional test instrumentation for testing conventional radars. Single tests and subtests designed to test radar components, transmitters, receivers, antennas, etc., and ...

1984-01-01

257

Statistical MIMO Radar.  

National Technical Information Service (NTIS)

Inspired by recent advances in multiple-input multiple-output (MIMO) communications, we introduce the statistical MIMO radar concept. Unlike beamforming, array radar, or STAP, which presuppose a high correlation between signals either transmitted or recei...

A. Haimovich E. Fishler R. Blum D. Chizhik R. Valenzuela

2004-01-01

258

Terminal doppler weather radar (TDWR) build 5B operational test and evaluation (OT&E) integration and OT&E operational test plan  

NASA Astrophysics Data System (ADS)

The Terminal Doppler Weather Radar (TDWR) Build 5B Enhancement Operational Test and Evaluation (OT&E) Integration and OT&E Operational Test Plan provides the overall philosophy and approach to Build 5B OT&E testing, and identifies OT&E objectives, responsibilities, and resources. The TDWR Build 5B Enhancement provides connectivity to the Low Level Wind Shear Alert System (LLWAS) III to display LLWAS III data along with TDWR hazardous weather data on TDWR Geographic Situation Displays (GSD) and Ribbon Display Terminals (RDT). The TDWR Build 5B OT&E is scheduled to occur at the TDWR sites in Denver, CO, November and December 1994, and in Orlando, FL, spring 1995.

Martinez, Radame; Viveiros, Steven; Wedge, Donne; Guthlein, Peter

1995-03-01

259

Evaluation of cloud microphysics simulated by a meso-scale model coupled with a bin-based scheme using observation data by W-band radar  

Microsoft Academic Search

Radar reflectivity factors measured by W-band radars were directly compared with the corresponding values calculated from a three-dimensional non-hydrostatic meso-scale model coupled with a bin-based cloud microphysical scheme. Three case studies are studied: one targets a part of shipborne observation using 95 GHz Doppler radar over the Pacific Ocean near Japan in May 2001; other two aim at two short

T. Iguchi; N. Teruyuki; A. Khain; K. Saito; T. Takemura; H. Okamoto; T. Nishizawa; W. Tao

2009-01-01

260

Controlling radar signature  

SciTech Connect

Low observable technologies for military and tactical aircraft are reviewed including signature-reduction techniques and signal detection/jamming. Among the applications considered are low-signature sensors and the reduction of radar cross section in conjunction with radar-absorbing structures and materials. Technologies for reducing radar cross section are shown to present significant technological challenges, although they afford enhanced aircraft survivability.

Foulke, K.W. (U.S. Navy, Naval Air Warfare Center, China Lake, CA (United States))

1992-08-01

261

CHIRP Doppler radar  

Microsoft Academic Search

The present investigation is concerned with the concept of a combination of the clinical procedure of reconstruction tomography with the radar processing for linear FM pulse compression. An approach based on such a combination is to be employed to map radar backscatter energy. Radar systems employing pulse compression of linear frequency modulated (CHIRP) pulses are considered along with the inversion

M. Bernfeld

1984-01-01

262

Aviation weather radar  

Microsoft Academic Search

The Federal Aviation Administration has established three ground-based weather radar programs. The terminal Doppler weather radar (TDWR) and weather system processor (WSP) provide wind shear detection capability for air traffic controllers in the terminal area. These systems also reduce weather related delays. The next generation weather radar (NEXRAD) is used by the FAA to improve safety and reduce weather related

D. H. Turnbull

1995-01-01

263

Feasibility of STAP for passive GSM-based radar  

Microsoft Academic Search

In this paper, we examine the feasibility of applying space-time adaptive processing (STAP) to bistatic passive radars using illuminators of opportunity. The transmitters considered are GSM base stations and are non-cooperative. Although STAP has been extensively applied to signals from pulse-Doppler radars, it was never applied to arbitrary signals arising from illuminators of opportunity. We show that by computing the

Xavier Neyt; Jacques Raout; Mireille Kubica; Virginie Kubica; Serge Roques; Marc Acheroy; Jacques G. Verly

2006-01-01

264

52. View from ground level showing lower radar scanner switch ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

52. View from ground level showing lower radar scanner switch with open port door in radar scanner building 105 showing emanating waveguides from lower switch in vertical run; photograph also shows catwalk to upper scanner switch in upper left side of photograph and structural supports. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

265

Mitigation of radar interference with WiMAX systems  

Microsoft Academic Search

In this paper, the effect of radar-induced electromagnetic interference (EMI) on a WiMAX base station receiver is investigated through the use of MATLAB models. The three types of radar pulses investigated include: a short, wideband, chirp pulse; a long, narrowband, chirp pulse; and a long, sinusoidal pulse. The benefits of superimposing these pulses in the guard interval and\\/or guard band

Lawrence Cohen; Erica Daly; Jean DeGraaf; Kim Scheff

2010-01-01

266

Harmonic Radar Literature Harmonisk Radar - en Litteraturstudie.  

National Technical Information Service (NTIS)

A harmonic radar sends on a given frequency f sub o and receives on another frequency usually 3 f sub o. The overtone is generated on joints between the metal parts of the radar target. The generated high harmonic frequency is very weak, which is why this...

B. Jansson

1980-01-01

267

Aging of nuclear station diesel generators: Evaluation of operating and expert experience: Phase 1, Study  

SciTech Connect

Pacific Northwest Laboratory evaluated operational and expert experience pertaining to the aging degradation of diesel generators in nuclear service. The research, sponsored by the US Nuclear Regulatory Commission (NRC), identified and characterized the contribution of aging to emergency diesel generator failures. This report, Volume I, reviews diesel-generator experience to identify the systems and components most subject to aging degradation and isolates the major causes of failure that may affect future operational readiness. Evaluations show that as plants age, the percent of aging-related failures increases and failure modes change. A compilation is presented of recommended corrective actions for the failures identified. This study also includes a review of current, relevant industry programs, research, and standards. Volume II reports the results of an industry-wide workshop held on May 28 and 29, 1986 to discuss the technical issues associated with aging of nuclear service emergency diesel generators.

Hoopingarner, K.R.; Vause, J.W.; Dingee, D.A.; Nesbitt, J.F.

1987-08-01

268

Evaluation of 25 y of environmental monitoring data around Madras Atomic Power Station (MAPS), Kalpakkam, India.  

PubMed

The Environmental Survey Laboratory at Kalpakkam, India carries out elaborate monitoring programme involving atmospheric, terrestrial and aquatic samples for radioactivity to evaluate the impact of operating two pressurised heavy water reactors. This paper presents the evaluation of 25 y (1983-2008) data. Statistical analysis of the environmental data for different radionuclides showed that the data best fits log-normal distribution. The data analysed showed that fission products such as (137)Cs, (90)Sr and (131)I were due to global fallout only. A ratio of 0.2 was obtained for (90)Sr to (137)Cs in air filter samples, only during Chernobyl accident period. The transfer factor of (137)Cs and (90)Sr for rice was computed to be 0.23 and 0.03 and vegetables 0.25 and 0.10, respectively. Activation products (3)H and (41)Ar are the only radionuclides that are related to MAPS operation. A strong correlation (r = 0.9) was observed between (3)H activity in air and (3)H discharged to the atmosphere. A similar correlation (r = 0.8) was observed in (3)H concentration in seawater and (3)H discharged in the liquid waste. The annual internal dose due to (3)H and annual external dose due to (41)Ar evaluated in the last 25 y show that the members of the public received less than 2 % of the dose limit (1 mSv y(-1)) set by ICRP 72. PMID:20829204

Rajaram, S; Brindha, J Thulasi; Sreedevi, K R; Manu, Anitha; Thilakavathi, A; Ramkumar, S; Santhanakrishnan, V; Balagurunathan, M R; Jesan, T; Kannan, V; Hegde, A G

2010-09-08

269

Evaluation of bateriologial and sanitary quality of drinking water stations and water tankers in Makkah Al-Mokarama.  

PubMed

The present study was conducted to evaluate the bacteriological and sanitary quality of drinking water produced in Makkah Al-Mokarama during the high season in the month of Ramadan. Water samples were collected both from the drinking water stations and the water tankers (in Arabic language called whitats) used to transport and distribute water in different places in the Holy city. Water samples were analyzed to determine the densities of HPC at 22 and 37 degrees C, total coliforms, E. coli and S. aureus. The bacteriological analysis of drinking water samples at 37 degrees C proved that 6.7-33.3, 20-46.7, 0-20 and 0-6.7% of total water samples contained HPC, total coliforms, E. coli and S. aureus, respectively which were higher than the safe limits for drinking water. The bacterial analysis of drinking water varied from one water station to another. On the other hand, drinking water transported by tankers appeared to be in the lowest category of water quality. Because out of total water samples 40-59%, 60-68.8%, 31.2-37.5%, 10-25% contained HPC, total coliforms, E. coli and S. aureus, respectively, which were higher than the established safe limits of drinking water. One possible reason for poor quality of drinking water could be attributed to the application of inadequate water disinfection treatments and also the absence of sanitary aspects as supported by the bacteriological analysis which holds true especially for water supplied by tankers. In conclusion, it is important to apply proper water disinfection measures and provide sanitary monitoring programs during the production of drinking water as a whole and for the water tanker in particular. PMID:19579978

Mihdhdir, Alaa A

2009-02-15

270

Interferometric radar measurements  

NASA Astrophysics Data System (ADS)

The United States Army Space and Missile Defense Command (USASMDC) has interest in a technology demonstration that capitalizes on investment in fire control and smart interceptor technologies that have matured beyond basic research. The concept SWORD (Short range missile defense With Optimized Radar Distribution) consists of a novel approach utilizing a missile interceptor and interferometric fire control radar. A hit-to-kill, closed-loop, command guidance scheme is planned that takes advantage of extremely accurate target and interceptor state vectors derived via the fire control radar. The fire control system has the capability to detect, track, and classify multiple threats in a tactical regime as well as simultaneously provide command guidance updates to multiple missile interceptors. The missile interceptor offers a cost reduction potential as well as an enhancement to the kinematics range and lethality over existing SHORAD systems. Additionally, the Radio Frequency (RF) guidance scheme offers increased battlefield weather performance. The Air Defense (AD) community, responding to current threat capabilities and trends, has identified an urgent need to have a capability to counter proliferated, low cost threats with a low cost-per-kill weapon system. The SWORD system will offer a solution that meets this need. The SWORD critical technologies will be identified including a detailed description of each. Validated test results and basic principles of operation will be presented to prove the merit of past investments. The Deputy Assistant Secretary of the Army for Research and Technology (DAS(R&T) has a three- year Science and Technology Program to evaluate the errors and proposed mitigation techniques associated with target spectral dispersion and range gate straddle. Preliminary bench-top experiment results will be presented in this paper.

Smith, Ronald A.; Shipman, Mark; Holder, E. J.; Williams, James K.

2002-08-01

271

Aging of nuclear station diesel generators: Evaluation of operating and expert experience: Workshop  

SciTech Connect

Pacific Northwest Laboratory (PNL) evaluated operational and expert experience pertaining to the aging degradation of diesel generators in nuclear service. The research, sponsored by the US Nuclear Regulatory Commission (NRC), identified and characterized the contribution of aging to emergency diesel generator failures. This report, Volume II, reports the results of an industry-wide workshop held on May 28 and 29, 1986, to discuss the technical issues associated with aging of nuclear service emergency diesel generators. The technical issues discussed most extensively were: man/machine interfaces, component interfaces, thermal gradients of startup and cooldown and the need for an accurate industry database for trend analysis of the diesel generator system.

Hoopingarner, K.R.; Vause, J.W.

1987-08-01

272

The Goldstone solar system radar: A science instrument for planetary research  

NASA Astrophysics Data System (ADS)

The Goldstone Solar System Radar (GSSR) station at NASA's Deep Space Communications Complex in California's Mojave Desert is described. A short chronological account of the GSSR's technical development and scientific discoveries is given. This is followed by a basic discussion of how information is derived from the radar echo and how the raw information can be used to increase understanding of the solar system. A moderately detailed description of the radar system is given, and the engineering performance of the radar is discussed. The operating characteristics of the Arcibo Observatory in Puerto Rico are briefly described and compared with those of the GSSR. Planned and in-process improvements to the existing radar, as well as the performance of a hypothetical 128-m diameter antenna radar station, are described. A comprehensive bibliography of referred scientific and engineering articles presenting results that depended on data gathered by the instrument is provided.

Dvorsky, J. D.; Renzetti, N. A.; Fulton, D. E.

1992-12-01

273

Radar Meteorology Tutorial  

NSDL National Science Digital Library

Brian McNoldy at Multi-community Environmental Storm Observatory (MESO) educates the public about the use of radar in meteorology in this pdf document. After reading about the history of radar, visitors can find out how radar can detect storms by transmitting a high-power beam of radiation. Students can learn how scatter, absorption, frequencies, scan angles, and moments impact the radar display. With the help of many example images, the author also discusses how to interpret the images collected. At the end of the online document, visitors can learn about the characteristics and capabilities of NEXRAD WSR-88D, the radar used throughout the United States.

Mcnoldy, Brian

2007-08-16

274

Cloud and Precipitation Radar  

NASA Astrophysics Data System (ADS)

Precipitation or weather radar is an essential tool for research, diagnosis, and nowcasting of precipitation events like fronts or thunderstorms. Only with weather radar is it possible to gain insights into the three-dimensional structure of thunderstorms and to investigate processes like hail formation or tornado genesis. A number of different radar products are available to analyze the structure, dynamics and microphysics of precipitation systems. Cloud radars use short wavelengths to enable detection of small ice particles or cloud droplets. Their applications differ from weather radar as they are mostly orientated vertically, where different retrieval techniques can be applied.

Hagen, Martin; Höller, Hartmut; Schmidt, Kersten

275

Structural review of the San Onofre Nuclear Generation Station Unit 1 containment structure under combined loads. Systematic Evaluation Program  

SciTech Connect

This report is a structural assessment of the containment structure of the San Onofre Nuclear Generation Station Unit 1, performed for the Nuclear Regulatory Commission as part of the Systematic Evaluation Program (SEP). The San Onofre assessment focused on the overall structural integrity of the containment structure under a safe shutdown earthquake an a postulated design basis accident. The safe shutdown earthquake was represented by the Housner Spectra, scaled to 0.67 g peak ground acceleration. The postulated design basis accident was either a loss of coolant accident or a main steam line break. Several combined stresses were evaluated for their adherence to the 1980 edition of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code allowables. All the calculated stress intensities were found to be acceptable according to this code except the general primary membrane stress due to combined dead and pressure loads under level A service limits. Because the containment structure was previously tested under combined dead and pressure loads for a higher peak pressure than the one used here, this study concluded that it was acceptable.

Lo, T.Y.

1982-05-01

276

Characterization of ice cloud properties obtained by shipborne radar/lidar over the tropical western Pacific Ocean for evaluation of an atmospheric general circulation model  

NASA Astrophysics Data System (ADS)

This study analyzed 95-GHz radar/lidar data collected from the R/V Mirai over the tropical western Pacific to characterize the vertical distribution of ice cloud effective radius reff, ice water content IWC, and in-cloud vertical velocity of the region in conjunction with weather regimes classified by International Satellite Cloud Climatology Project (ISCCP) cluster analysis. Ice clouds observed from the Mirai were roughly consistent with the ISCCP weather regimes; more convectively active regimes had larger amounts of high cloud consisting of deeper cloud with larger ice water path (IWP) and precipitating ice fraction. Ice cloud microphysics of the Center for Climate System Research, National Institute for Environmental Studies, Frontier Research Center for Global Change atmospheric general circulation model (AGCM) was then evaluated using the radar-lidar simulator and ISCCP weather regimes for comparison of the statistics at different scales. The model tended to produce a high cloud fraction that was two times larger in the cirrus regimes but 50% lower in the deepest convective regime. The simulated IWP could only weakly reproduce the observed variety and generally underestimated the observed values despite the weather regimes. Cutoff in the simulated grid mean IWC around 0.1 g-3 was too small, especially above 11 km. The AGCM successfully predicted the observed frequency distribution for reff above 11 km, but produced large overestimation in the peak value below 11 km due to the excessively large fraction of reff ˜100 ?m. Establishing a cutoff for cloud ice at reff > 120 ?m was found to be quite reasonable, although it would miss some of the larger particles that were observed.

Sato, Kaori; Okamoto, Hajime; Takemura, Toshihiko; Kumagai, Hiroshi; Sugimoto, Nobuo

2010-08-01

277

Accessibility and Utilization of WSR-88D Radar Precipitation Data for Natural Resource Modeling Applications  

Microsoft Academic Search

The National Weather Service (NWS) operates approximately 160 WSR-88D radar-precipitation stations as part of a Next Generation Radar (NEXRAD) program that began implementation in 1992. Among other products, these radar sites provide spatial rainfall estimates, at approximately 4 km2 resolution (Stage 1, Level 3 data), with nominal coverage of 96% of the coterminous United States. Effective coverage is much less

S. P. Hardegree

2001-01-01

278

Design, Evaluation and Construction of TEXESS and LUXESS, and Research in Mini-Array Technology and Use of Data from Single Stations and Sparse Networks.  

National Technical Information Service (NTIS)

Objectives of the contract are twofold: (1) to conduct research in seismic mini-array technology use of data from single stations-sparse networks, and (2) to design, evaluate, and construct 2 mini-arrays, TEXESS (Texas Experimental Seismic System) in s.w....

E. Herrin P. Golden H. Robertson

1994-01-01

279

Design, Evaluation, and Construction of Texess and Luxess, and Research in Mini-Array Technology and use of Data from Single Stations and Sparse Networks. Phase 3.  

National Technical Information Service (NTIS)

Objectives are : (1) conduct research in seismic mini-array technology and single stations and sparse networks data, (CLIN 1) and (2) design, evaluate, and construct TEXESS, in Southwest Texas, and LUXESS, northeast of Luxor, Egypt, (CLIN 2), along the li...

E. Herrin P. Golden H. Robertson

1994-01-01

280

Health hazard evaluation report HETA 93-1062-2558, Texas Utilities Electric Company, Martin Lake Steam Electric Station, Tatum, Texas  

Microsoft Academic Search

In response to a request from workers at the Texas Utilities Electric Company (SIC-4911), Martin Lake Steam Electric Station in Tatum, Texas, the incidence of neurologic symptoms and exposure to electromagnetic fields and organophosphates were investigated. Workers reported neurological symptoms, including memory loss, dizziness and fatigue. A site visit to the station revealed electromagnetic field levels below the current occupational

R. Malkin; C. E. Moss; C. M. Reh; M. Ragab

1996-01-01

281

Evaluating Bicycling Commuter Experiences at Texas A&M University and Adjacent Areas in the City of College Station, Texas.  

National Technical Information Service (NTIS)

The university-oriented community of College Station, Texas offers a great opportunity for bicycle commuting. Both the City of College Station and Texas A&M University (TAMU) have taken steps to add facilities for pedestrians and bicycles in and around ca...

R. Rabinowitz D. Spillane

2005-01-01

282

Radar resource sharing study  

NASA Astrophysics Data System (ADS)

The Radar Resource Sharing Study was undertaken to evaluate the relative advantages or three candidate technologies for implementing a shared beamformer for a dual band (S and UHF) airborne surveillance radar. The beamformer was required to interface with the two active array apertures and perform the signal combining and distribution functions necessary to produce the receive and transmit beams required for each band. The objective was to compare the three approaches in terms of size, weight, power consumption and hardware sharing, based on 1997 technology projections. The candidate beam-former technologies investigated were Conventional, Digital and Optical beamformers. In the digital and optical cases, technology limitations precluded accomplishing all of the required beamformer functions. Therefore, hybrid approaches which employed each of these technologies to the maximum practical extent were devised. The study commenced in September 1992 and was conducted primarily on the basis of beamformer requirements for monostatic operation. Later the scope was expanded to consider a bistatic receive implementation having significantly different beam requirements.

Gouse, Ronald; Clancy, John

1995-03-01

283

Rendezvous radar for the orbital maneuvering vehicle  

NASA Astrophysics Data System (ADS)

This paper describes the development of the Rendezvous Radar Set (RRS) for the Orbital Maneuvering Vehicle (OMV) for the National Aeronautics and Space Administration (NASA). The RRS was to be used to locate, and then provide vectoring information to, target satellites (or Shuttle or Space Station) to aid the OMV in making a minimum-fuel-consumption approach and rendezvous. The RRS design is that of an X-Band, all solid-state, monopulse tracking, frequency hopping, pulse-Doppler radar system. The development of the radar was terminated when the OMV prime contract to TRW was terminated by NASA. At the time of the termination, the development was in the circuit design stage. The system design was virtually completed, the PDR had been held. The RRS design was based on Motorola's experiences, both in the design and production of radar systems for the US Army and in the design and production of hi-rel communications systems for NASA space programs. Experience in these fields was combined with the latest digital signal processor and micro-processor technology to design a light-weight, low-power, spaceborne radar. The antenna and antenna positioner (gimbals) technology developed for the RRS is now being used in the satellite-to-satellite communication link design for Motorola's Iridium telecommunications system.

Locke, John W.; Olds, Keith; Parks, Howard

284

7. CLOSEUP FRONT VIEW OF RADAR SYSTEM EMITTER/ANTENNA (TYPICAL DEVICE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. CLOSE-UP FRONT VIEW OF RADAR SYSTEM EMITTER/ANTENNA (TYPICAL DEVICE PHOTOGRAPH). - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

285

Evaluation of R. Paul Smith Steam Electric Station thermal discharge effects on finfish and macroinvertebrate communities, summer/fall 1980. Final report  

SciTech Connect

The objectives of the study were to evaluate the thermal effects of the R. P. Smith steam Electric Station upon the finfish and macroinvertebrates communities during summer and fall, on the Potomac River. The finfish community was sampled during August and September 1980 with electrofishing gear. The increased water temperature along the Maryland shore appeared to influence the distribution of spotfin shiner and smallmouth bass. Carp, although not statistically tested, appeared to be more abundant in the thermal plume than at stations outside the thermal plume. The thermal discharge exhibited no discernible influence on the composition of the benthic or drift macroinvertebrate communities.

Not Available

1981-02-01

286

Results from UHF and HF radar studies of ionospheric interaction experiments at HAARP  

Microsoft Academic Search

High power HF radiowave experiments have begun at the HAARP Ionospheric Research Observatory in Gakona Alaska The SuperDARN HF radar station in Kodiak Alaska is now routinely employed to monitor HF backscatter from irregularities formed in the interaction volume over HAARP A 16-panel prototype of a new UHF radar facility MUIR has recently become operational on the HAARP site Complementary

J. Sheerin; W. Bristow; B. Watkins; S. Oyama; C. Heinselman

2006-01-01

287

Results from UHF and HF Radar Studies of Ionospheric Interaction Experiments at HAARP  

Microsoft Academic Search

High power HF radiowave experiments have begun at the HAARP Ionospheric Research Observatory in Gakona, Alaska. The SuperDARN HF radar station in Kodiak, Alaska is now routinely employed to monitor HF backscatter from irregularities formed in the interaction volume over HAARP. A 16-panel prototype of a new UHF incoherent scatter radar facility, AMISR, has recently become operational on the HAARP

J. P. Sheerin; R. Ilie; E. L. Roesler; W. A. Bristow; B. J. Watkins; S. Oyama

2005-01-01

288

A novel noncooperative near-range radar network for traffic guidance and control on airport surfaces  

Microsoft Academic Search

The concept of a novel modular structured near-range primary radar network (NRN) for guidance and control of airport surface traffic is presented. Several autonomously operating modules comprising of four radar stations cover all relevant airport areas or, alternatively, are integrated in a complex structured surveillance system by data fusion; then only selected areas have to be covered. Each sensor of

K.-H. Bethke; B. Rode; M. Schneider; A. Schroth

1993-01-01

289

10. Perimeter acquisition radar power plant (upper level) room #219E, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. Perimeter acquisition radar power plant (upper level) room #219E, station services room; showing air compressors which provide diesel generators with internal power kick-on - Stanley R. Mickelsen Safeguard Complex, Perimeter Acquisition Radar Power Plant, In Limited Access Area, Southwest of PARB at end of Service Road B, Nekoma, Cavalier County, ND

290

The Benefit of Polarimetric Radar in Hydrologic Modeling  

NASA Astrophysics Data System (ADS)

Beginning in 2010, the entire WSR-88D radar network will be upgraded with dual-polarization capability. Polarimetric radar has shown benefits in removing artifacts from rainfall rate products due to non- meteorological scatterers, identifying hydrometeor phases, habits, and types, and improving estimates of heavy rainfall especially when mixed with hail. Previous hydrologic studies have included polarimetric rainfall estimates, but typically have focused on a single event using a particular hydrologic model. The intention of this study is to evaluate the general hydrologic performance of several rainfall algorithms which are based on variables collected by the polarimetric prototype of the WSR-88D, KOUN. We have concentrated our study on the heavily instrumented Ft. Cobb basin in Oklahoma for several events occurring over a three-year period, including an extreme event from a tropical storm that had a return period greater than 100 years. The Ft. Cobb basin is 813 km2 in area and includes the USDA's Agricultural Research Service's Micronet, a network of 15 stations that measure air temperature, rainfall, relative humidity, solar radiation, soil temperature at four depths, and soil water content at three depths. The high- density rain gauge network is used to evaluate the remote-sensing rainfall algorithms. In addition, we have set up and calibrated three different hydrologic models that have various levels of complexity ranging from purely empirical to distributed parameter, physically-based structures. This study will quantify the skill of the various hydrologic model simulations conditioned on the polarimetric rainfall inputs being investigated. Benchmark simulations are produced from rainfall algorithms using the standard WSR-88D reflectivity-to- rainfall (Z-R) relation as well as a rain gauge-only product, all of which are compared to observed streamflow at three USGS stations.

Gourley, J. J.; Giangrande, S.; Schuur, T.; Hong, Y.; Flamig, Z.

2008-12-01

291

Health-hazard evaluation report HETA 89-262-1994, Chapman Corporation, Albright Power Station, Albright, West Virginia  

SciTech Connect

In response to a request from the International Brotherhood of Electrical Workers, Local 425, an evaluation was made of possible asbestos exposures to electrical workers employed by Chapman Corporation engaged in electrical rewiring tasks on a boiler at the Albright Power Station, Albright, West Virginia. At the time the survey was undertaken, a complete refurbishing of boiler number 3 was being performed, part of which included an asbestos-abatement project. The electricians in question did not work inside the asbestos-containment area during the survey, but they did perform work outside and around the asbestos-containment area. Air sampling results indicated that asbestos-fiber releases did occur outside the containment area. Bulk samples of settled dust revealed asbestos contamination in the work areas surrounding the boiler. There were several deficiencies in the abatement program, including the lack of adequate containment and breaches in the enclosure. The study concludes that workers in the vicinity of this boiler had potential exposure to airborne asbestos fibers. Recommendations are made to help management representatives minimize potential risks through the establishment of a comprehensive asbestos-abatement program and policies.

Stephenson, R.L.

1989-11-01

292

Kinetic evaluation of H2S and NH3 biofiltration for two media used for wastewater lift station emissions.  

PubMed

In this study, biofiltration using a natural wood chip medium and a commercial biofiltration medium was evaluated for the removal of moderate concentrations of hydrogen sulfide (H2S) (up to 100 parts per million by volume [ppmv]) in the presence of significant concentrations of ammonia (NH3). These levels were chosen as representative of wastewater lift station emissions in the Brownsville, TX, area. NH3-removing portions of the biofilms may compete with H2S-removing portions and inhibit H2S removal. H2S process removal efficiencies for the commercial and natural media ranged from 90 to 96% depending on inlet loading and media type and bed height. Kinetic analysis of the H2S removal process followed apparent first-order reaction behavior. The average first-order reaction rates were 0.03 sec(-1) for the commercial medium and 0.09 sec(-1) for the natural medium. Pressure drops across the columns ranged from 0.41 in. H2O/ft for the commercial medium to 1.41 in. H2O/ft for the natural medium. NH3 gas levels of up to 80 ppmv did not affect the H2S removal process efficiency, and calculated kinetic rate constants for H2S removal remained almost the same. The NH3 gas also was removed simultaneously with the H2S up to 98% removal efficiency by the commercial medium. PMID:14871010

Jones, Kim D; Martinez, Al; Maroo, Ketankumar; Deshpande, Sonali; Boswell, James

2004-01-01

293

Technical evaluation report on the proposed design modifications and technical-specification changes on grid voltage degradation for the San Onofre Nuclear Genetating Station, Unit 1  

SciTech Connect

This report documents the technical evaluation of the proposed design modifications and Technical Specification changes for protection of Class 1E equipment from grid voltage degradation for the San Onofre Nuclear Generating Station, Unit 1. The review criteria are based on several IEEE standards and the Code of Federal Regulations. The evaluation finds that the proposed design modifications and Technical Specification changes will ensure that the Class 1E equipment will be protected from sustained voltage degradation.

Selan, J.C.

1982-05-26

294

Technical evaluation report on the monitoring of electric power to the reactor-protection system for the Pilgrim Nuclear Power Station  

SciTech Connect

This report documents the technical evaluation of the monitoring of electric power to the reactor protection system (RPS) at the Pilgrim Nuclear Power Station. The evaluation is to determine if the proposed design modification will protect the RPS from abnormal voltage and frequency conditions which could be supplied from the power supplies and will meet certain requirements set forth by the Nuclear Regulatory Commission. The proposed design modifications will protect the RPS from sustained abnormal voltage and frequency conditions from the supplying sources.

Selan, J.C.

1982-04-29

295

30. Perimeter acquisition radar building room #318, showing radar control. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. Perimeter acquisition radar building room #318, showing radar control. Console and line printers - Stanley R. Mickelsen Safeguard Complex, Perimeter Acquisition Radar Building, Limited Access Area, between Limited Access Patrol Road & Service Road A, Nekoma, Cavalier County, ND

296

Millimeter Wave Polarimetric Monopulse Radar Debugging System  

Microsoft Academic Search

For testing millimeter wave polarimetric monopulse radar and testing algorithms for polarimetric radar, millimeter wave polarimetric monopulse radar debugging system is proposed in this paper. Polarimetric radar, as a kind of radar with strong counter-countermeasure capability, is more and more popular used nowadays. The cost of polarimetric radar is more expensive than traditional single-polarimetric radar. Millimeter wave polarimetric monopulse radar

Jin Tao; Qi Xiaohui; Zhang Min; Qiao Xiaolin; Yuan Shuqing; Zhang Qunxing

2007-01-01

297

Performance and evaluation of gas engine driven rooftop air conditioning equipment at the Willow Grove (PA) Naval Air Station  

SciTech Connect

In a field evaluation conducted for the US Department of Energy (DOE) Office of Federal Energy Management Program (FEMP), the Pacific Northwest Laboratory (PNL) examined the performance of a new US energy-related technology under the FEMP Test Bed Demonstration Program. The technology was a 15-ton natural gas engine driven roof top air conditioning unit. Two such units were installed on a naval retail building to provide space conditioning to the building. Under the Test Bed Demonstration Program, private and public sector interests are focused to support the installation and evaluation of new US technologies in the federal sector. Participating in this effort under a Cooperative Research and Development Agreement (CRADA) with DOE were the American Gas Cooling Center, Philadelphia Electric Company, Thermo King Corporation, and the US Naval Air Station at Willow Grove, Pennsylvania. Equipment operating and service data as well as building interior and exterior conditions were secured for the 1992 cooling season. Based on a computer assessment of the building using standard weather data, a comparison was made with the energy and operating costs associated with the previous space conditioning system. Based on performance during the 1992 cooling season and adjusted to a normal weather year, the technology will save the site $6,000/yr in purchased energy costs. An additional $9,000 in savings due to electricity demand ratchet charge reductions will also be realized. Detailed information on the technology, the installation, and the results of the technology test are provided to illustrate the advantages to the federal sector of using this technology. A history of the CRADA development process is also reported.

Armstrong, P.R.; Conover, D.R.

1993-05-01

298

Assessment of Electromagnetic Requirements for UWB Through-Wall Radar  

Microsoft Academic Search

This paper investigates electromagnetic requirements for ultra-wideband (UWB) through-wall radar. It includes the evaluation of propagation loss, dynamic range and radar resolution for typical through-wall scenarios. The evaluation results in analysis and comparison of different transmission schemes.

X. Zhuge; T. G. Savelyev; A. G. Yarovoy

2007-01-01

299

Dependence of Radar Backscatter on the Energetics of the Air-Sea Interface.  

National Technical Information Service (NTIS)

The Normalized Radar Cross-Section (NRCS), the fundamental measurement made by radar scatterometers, was obtained as part of the Water-Air Vertical Exchanges 1987 (WAVES87) experiment. The experiment was designed to evaluate the effects of environmental p...

M. C. Colton

1989-01-01

300

Reflectivity retrieval in a networked radar environment  

NASA Astrophysics Data System (ADS)

Monitoring of precipitation using a high-frequency radar system such as X-band is becoming increasingly popular due to its lower cost compared to its counterpart at S-band. Networks of meteorological radar systems at higher frequencies are being pursued for targeted applications such as coverage over a city or a small basin. However, at higher frequencies, the impact of attenuation due to precipitation needs to be resolved for successful implementation. In this research, new attenuation correction algorithms are introduced to compensate the attenuation impact due to rain medium. In order to design X-band radar systems as well as evaluate algorithm development, it is useful to have simultaneous X-band observation with and without the impact of path attenuation. One way to obtain that data set is through theoretical models. Methodologies for generating realistic range profiles of radar variables at attenuating frequencies such as X-band for rain medium are presented here. Fundamental microphysical properties of precipitation, namely size and shape distribution information, are used to generate realistic profiles of X-band starting with S-band observations. Conditioning the simulation from S-band radar measurements maintains the natural distribution of microphysical parameters associated with rainfall. In this research, data taken by the CSU-CHILL radar and the National Center for Atmospheric Research S-POL radar are used to simulate X-band radar variables. Three procedures to simulate the radar variables at X-band and sample applications are presented. A new attenuation correction algorithm based on profiles of reflectivity, differential reflectivity, and differential propagation phase shift is presented. A solution for specific attenuation retrieval in rain medium is proposed that solves the integral equations for reflectivity and differential reflectivity with cumulative differential propagation phase shift constraint. The conventional rain profiling algorithms that connect reflectivity and specific attenuation can retrieve specific attenuation values along the radar path assuming a constant intercept parameter of the normalized drop size distribution. However, in convective storms, the drop size distribution parameters can have significant variation along the path. In this research, a dual-polarization rain profiling algorithm for horizontal-looking radars incorporating reflectivity as well as differential reflectivity profiles is developed. The dual-polarization rain profiling algorithm has been evaluated with X-band radar observations simulated from drop size distribution derived from high-resolution S-band measurements collected by the CSU-CHILL radar. The analysis shows that the dual-polarization rain profiling algorithm provides significant improvement over the current algorithms. A methodology for reflectivity and attenuation retrieval for rain medium in a networked radar environment is described. Electromagnetic waves backscattered from a common volume in networked radar systems are attenuated differently along the different paths. A solution for the specific attenuation distribution is proposed by solving the integral equation for reflectivity. The set of governing integral equations describing the backscatter and propagation of common resolution volume are solved simultaneously with constraints on total path attenuation. The proposed algorithm is evaluated based on simulated X-band radar observations synthesized from S-band measurements collected by the CSU-CHILL radar. Retrieved reflectivity and specific attenuation using the proposed method show good agreement with simulated reflectivity and specific attenuation.

Lim, Sanghun

301

Evaluating spatial variability of free-phase gas in peat using ground-penetrating radar and direct measurement  

NASA Astrophysics Data System (ADS)

Several recent studies have estimated that peatlands may have substantial quantities (up to 15-20% by volume) of biogenic free-phase gas (FPG) below the water table. The presence, distribution, and release of this FPG play important roles in peatland hydrology and biogeochemistry. Despite its importance, investigation of FPG is difficult because most measurement techniques involve disturbance of the peat, potentially altering gas volume in the process. Ground-penetrating radar (GPR) provides a noninvasive approach to quantify gas content in peat; however, its use for investigating variability in gas content at the microform scale across a peatland and with depth has been limited to date. We investigated variability in subsurface CH4 stock and FPG content between peatland microforms using (1) GPR and the common midpoint method to determine subsurface electromagnetic wave velocity and (2) direct measurement in order to estimate FPG content at three ridges and three hollows in a peatland in northern Alberta, Canada. Higher volumes of FPG were associated with higher CH4 concentrations, suggesting that a reliable estimate of gas volume could also serve as an estimate of stored CH4. In general, both methods found higher volumes of gas under ridges than hollows. When electromagnetic wave velocity was considered, a significant correlation was present with direct measurement of FPG volume. Zones with FPG content up to 20% of peat volume were observed throughout the peat profile including within the upper 1.5 m of peat. Further research is needed to determine physical, chemical, and biological controls on the variability of FPG volume in peat.

Strack, M.; Mierau, T.

2010-06-01

302

Impacts of polarimetric radar observations on hydrologic simulation  

NASA Astrophysics Data System (ADS)

This study presents an analysis of hydrologic simulations performed for a dataset of several rainfall-runoff events, including a 100-year event, that were captured by the polarimetric prototype of the WSR-88D radar, KOUN. The focus basin is the heavily instrumented Ft. Cobb basin in Oklahoma which features a Micronet, a network of 15 hydrometeorological stations, and four US Geological Survey stream gauges. The high-density rain gauge network was used to evaluate the polarimetric rainfall algorithms. We also set up and rigorously calibrated the National Weather Service Office of Hydrologic Development's 19-parameter distributed hydrologic model over a three-year period. Benchmark simulations were produced using inputs from the rain gauge-only product that was used for calibration. The hydrologic model was then forced with rainfall using the standard WSR-88D reflectivity-to-rainfall (Z-R) relation as well as recently proposed rainfall algorithms based on polarimetric variables. Ultimately, this study aims to answer: "What will polarimetric radar do for flash flood prediction?"

Gourley, Jonathan; Flamig, Zachary; Hong, Yang; Schuur, Terry; Giangrande, Scott; Vrugt, Jasper

2010-05-01

303

Holographic neural networks versus conventional neural networks: a comparative evaluation for the classification of landmine targets in ground-penetrating radar images  

NASA Astrophysics Data System (ADS)

This paper evaluates the performance of a holographic neural network in comparison with a conventional feedforward backpropagation neural network for the classification of landmine targets in ground penetrating radar images. The data used in the study was acquired from four different test sites using the landmine detection system developed by General Dynamics Canada Ltd., in collaboration with the Defense Research and Development Canada, Suffield. A set of seven features extracted for each detected alarm is used as stimulus inputs for the networks. The recall responses of the networks are then evaluated against the ground truth to declare true or false detections. The area computed under the receiver operating characteristic curve is used for comparative purposes. With a large dataset comprising of data from multiple sites, both the holographic and conventional networks showed comparable trends in recall accuracies with area values of 0.88 and 0.87, respectively. By using independent validation datasets, the holographic network"s generalization performance was observed to be better (mean area = 0.86) as compared to the conventional network (mean area = 0.82). Despite the widely publicized theoretical advantages of the holographic technology, use of more than the required number of cortical memory elements resulted in an over-fitting phenomenon of the holographic network.

Mudigonda, Naga R.; Kacelenga, Ray; Edwards, Mark

2004-09-01

304

Laser radar in robotics  

SciTech Connect

In this paper the authors describe the basic operating principles of laser radar sensors and the typical algorithms used to process laser radar imagery for robotic applications. The authors review 12 laser radar sensors to illustrate the variety of systems that have been applied to robotic applications wherein information extracted from the laser radar data is used to automatically control a mechanism or process. Next, they describe selected robotic applications in seven areas: autonomous vehicle navigation, walking machine foot placement, automated service vehicles, manufacturing and inspection, automotive, military, and agriculture. They conclude with a discussion of the status of laser radar technology and suggest trends seen in the application of laser radar sensors to robotics. Many new applications are expected as the maturity level progresses and system costs are reduced.

Carmer, D.C.; Peterson, L.M. [Environmental Research Inst. of Michigan, Ann Arbor, MI (United States)

1996-02-01

305

Radar in transition  

NASA Astrophysics Data System (ADS)

It is pointed out that radar engineers, at the end of 1984, find their field in transition between the conventional designs of the post War II era and the digitally controlled, solid-state systems which will be in place for the year 2000. The U.S. Navy has two major phased array radar systems in operation, including the rotating three-dimensional (3D) AN/SPS-48, and the phased-scanned AN/SPY-1 (Aegis) radars. The Aegis represents a major step beyond the conventional 3D and mechanical fire-control radars. However, it requires a special ship, dedicated to its use. Attention is given to questions regarding an extension of the application of Aegis technology to other U.S. Navy applications and to other navies, an ambitious solid-state radar program in the UK, and Army radars.

Barton, D. K.

1984-12-01

306

Health Hazard Evaluation Report HETA 93-1062-2558, Texas Utilities Electric Company, Martin Lake Steam Electric Station, Tatum, Texas.  

National Technical Information Service (NTIS)

In response to a request from workers at the Texas Utilities Electric Company (SIC-4911), Martin Lake Steam Electric Station in Tatum, Texas, the incidence of neurologic symptoms and exposure to electromagnetic fields and organophosphates were investigate...

R. Malkin C. E. Moss C. M. Reh M. Ragab

1996-01-01

307

Evaluation of Environmental Data Relating to Selected Nuclear Power Plant Sites: The Three Mile Island Nuclear Station Site.  

National Technical Information Service (NTIS)

Environmental monitoring data for the years 1973 and 1974 pertaining to the Three Mile Island Nuclear Station Unit 1, which began operation in early 1974, were analyzed by the most practical qualitative and quantitative methods. Terrestrial biotic resourc...

I. P. Murarka

1976-01-01

308

Test and Evaluation of Load Converter Topologies Used in the Space Station Freedom Power Management and Distribution DC Test Bed.  

National Technical Information Service (NTIS)

Power components hardware in support of the Space Station Freedom dc Electrical Power System were tested. One type of breadboard hardware tested is the dc Load Converter Unit, which constitutes the power interface between the electric power system and the...

R. C. Lebron A. C. Oliver R. F. Bodi

1991-01-01

309

Performance Evaluation of UHF RFID Technologies for Real-Time Bus Recognition in the Taipei Bus Station  

PubMed Central

Transport stations such as airports, ports, and railways have adopted blocked-type pathway management to process and control travel systems in a one-directional manner. However, this excludes highway transportation where large buses have great variability and mobility; thus, an instant influx of numerous buses increases risks and complicates station management. Focusing on Taipei Bus Station, this study employed RFID technology to develop a system platform integrated with modern information technology that has numerous characteristics. This modern information technology comprised the following systems: ultra-high frequency (UHF) radio-frequency identification (RFID), ultrasound and license number identification, and backstage graphic controls. In conclusion, the system enabled management, bus companies, and passengers to experience the national bus station's new generation technology, which provides diverse information and synchronization functions. Furthermore, this technology reached a new milestone in the energy-saving and efficiency-increasing performance of Taiwan's buses.

Own, Chung-Ming; Lee, Da-Sheng; Wang, Ti-Ho; Wang, De-Jun; Ting, Yu-Lun

2013-01-01

310

Performance evaluation of UHF RFID technologies for real-time bus recognition in the Taipei Bus Station.  

PubMed

Transport stations such as airports, ports, and railways have adopted blocked-type pathway management to process and control travel systems in a one-directional manner. However, this excludes highway transportation where large buses have great variability and mobility; thus, an instant influx of numerous buses increases risks and complicates station management. Focusing on Taipei Bus Station, this study employed RFID technology to develop a system platform integrated with modern information technology that has numerous characteristics. This modern information technology comprised the following systems: ultra-high frequency (UHF) radio-frequency identification (RFID), ultrasound and license number identification, and backstage graphic controls. In conclusion, the system enabled management, bus companies, and passengers to experience the national bus station's new generation technology, which provides diverse information and synchronization functions. Furthermore, this technology reached a new milestone in the energy-saving and efficiency-increasing performance of Taiwan's buses. PMID:23778192

Own, Chung-Ming; Lee, Da-Sheng; Wang, Ti-Ho; Wang, De-Jun; Ting, Yu-Lun

2013-06-18

311

Review of Radar Absorbing Materials.  

National Technical Information Service (NTIS)

Radar is a sensitive detection tool and since its development, methods for reducing microwave reflections have been explored. Radar absorbers can be classified as impedance matching or resonant absorbers. Radar absorbing materials are made from resistive ...

P. Saville

2005-01-01

312

Stations Outdoors  

ERIC Educational Resources Information Center

Described is a program of outdoor education utilizing activity-oriented learning stations. Described are 13 activities including: a pond study, orienteering, nature crafts, outdoor mathematics, linear distance measurement, and area measurement. (SL)

Madison, John P.; And Others

1976-01-01

313

Spaceborne Atmospheric Radar Technology  

Microsoft Academic Search

NASA is developing advanced instrument concepts and technologies for future spaceborne atmospheric radars, with the over-arching objectives of making such instruments more capable in supporting future science needs, and more cost effective. Two such examples are the Second-Generation Precipitation Radar (PR-2) and the Nexrad-In-Space (NIS). PR- 2 is a 14\\/35-GHz dual-frequency rain radar with a deployable 5- meter, wide-swath scanned

Eastwood Im; Stephen L. Durden

314

Use of a combined personal computer and Rock-Eval in an integrated petroleum evaluation work station to estimate volumes of hydrocarbons generated and migrated in sedimentary basins  

SciTech Connect

A petroleum evaluation work station consisting in a modified Rock-Eval apparatus connected to an IBM personal computer has been designed at Institut Francais du petrole to estimate the amount of hydrocarbon generated and migrated in sedimentary basins. The work-station is provided with specific software for Rock-Eval data analysis, quick determination of kinetic parameters (Optim model), and quantitative hydrocarbon generation (Matoil model). Along with the classical Rock-Eval parameters (S{sub 0}, S{sub 1}, S{sub 2}, TOC, and T{sub max}), new parameters concerning the source rocks, such as the transformation efficiency ratio (TER), the migration efficiency ration (MER), and the initial generation capacity (IGC), are defined. These new parameters combined with geological data give access to a rapid volumetric estimation (in 10{sup 6}MT/km{sup 2}) of hydrocarbon generation and migration in the studied area. These data can be displayed on different specific maps for rapid visualization. This work station has been successfully used in the Paris and Aquitaine basins, making possible a better assessment of their petroleum potential. The petroleum evaluation work station appears to be a very valuable tool that can be used in the different phases of exploration in a sedimentary basin.

Espitalie, J.; Lafargue, E.; Drouet, S. (Institut Francais du Petrole, Rueil-Malmaison)

1989-09-01

315

Monitoring by holographic radar systems  

NASA Astrophysics Data System (ADS)

Nowadays, radar technology represents a significant opportunity to collect useful information for the monitoring and conservation of critical infrastructures. Radar systems exploit the non-invasive interaction between the matter and the electromagnetic waves at microwave frequencies. Such an interaction allows obtaining images of the region under test from which one can infer the presence of potential anomalies such as deformations, cracks, water infiltrations, etc. This information turns out to be of primary importance in practical scenarios where the probed structure is in a poor state of preservation and renovation works must be planned. In this framework, the aim of this contribution is to describe the potentialities of the holographic radar Rascan 4/4000, a holographic radar developed by Remote Sensing Laboratory of Bauman Moscow State Technical University, as a non-destructive diagnostic tool capable to provide, in real-time, high resolution subsurface images of the sounded structure [1]. This radar provides holograms of hidden anomalies from the amplitude of the interference signal arising between the backscattered signal and a reference signal. The performance of the holographic radar is appraised by means of several experiments. Preliminary tests concerning the imaging below the floor and inside wood structures are carried out in controlled conditions at the Electromagnetic Diagnostic Laboratory of IREA-CNR. After, with reference to bridge monitoring for security aim, the results of a measurement campaign performed on the Musmeci bridge are presented [2]. Acknowledgments This research has been performed in the framework of the "Active and Passive Microwaves for Security and Subsurface imaging (AMISS)" EU 7th Framework Marie Curie Actions IRSES project (PIRSES-GA-2010-269157). REFERENCES [1] S. Ivashov, V. Razevig, I. Vasilyev, A. Zhuravlev, T. Bechtel, L. Capineri, The holographic principle in subsurface radar technology, International Symposium to Commemorate the 60th Anniversary of the Invention of Holography, Springfield, Massachusetts USA, October 27-29, pp. 183-197, 2008. [2] I. Catapano, L. Crocco, A. F. Morabito, F. Soldovieri, "Tomographic imaging of holographic GPR data for non-invasive structural assessment: the Musmeci bridge investigation", Nondestructive testing and evaluation, vol. 27, pp. 229-237, 2012.

Catapano, Ilaria; Crocco, Lorenzo; Affinito, Antonio; Gennarelli, Gianluca; Soldovieri, Francesco

2013-04-01

316

Artificial ionospheric mirrors for radar applications  

NASA Astrophysics Data System (ADS)

Recognition of performance limitations associated with traditional skywave over-the-horizon (OTH) HF radars has led a number of investigators to propose the creation of an Artificial Ionospheric Mirror (AIM) in the upper atmosphere, in order to reflect ground-based radar signals for OTH surveillance. The AIM is produced by beaming sufficient electromagnetic power to the lower ionosphere (around 70 km) to enhance the in situ ionization level to 10(exp 7) to 10(exp 8) electrons/cu cm, thereby providing an ionized layer capable of reflecting radar frequencies of 5 to 90 MHz. A baseline AIM system concept and an associated performance evaluation are presented, based upon the relevant ionization and propagation physics and in the context of air surveillance for the cruise missile threat. Results of the subject indicate that a system using this concept would both complement and enhance the performance of the existing skywave OTH radars.

Short, Robert D.; Wallace, Tom; Stewart, Clayton V.; Lallement, Pierre; Koert, Peter

1990-10-01

317

Borehole radar for geothermal applications  

SciTech Connect

An initial evaluation of a continuous wave borehole radar system with steerable antennas has been completed. Candidate antennas have been identified which meet the size requirements for borehole applications. The patterns of these antennas are not dependent on the properties of the surrounding media when the antenna dimensions are less than one-tenth wavelength. The beam patterns can be steered adequately to allow the volume of earth within several meters of a borehole to be investigated. 7 refs., 5 figs.

Scott, M.W.; Caffey, T.W.H.

1991-01-01

318

Technical-Evaluation Report on the Tests Conducted to Verify the Analyses Performed on the Adequacy of Station Electric Distribution-System Voltages for the Arkansas Nuclear One, Unit 1 (Docket No. 50-313).  

National Technical Information Service (NTIS)

This report supplements the technical evaluation documented in a separate report dated December 16, 1981 (UCID-19118) on the adequacy of station electric distribution system voltages for the Arkansas Nuclear One, Unit 1. The evaluation is to determine the...

J. C. Selan

1983-01-01

319

Technical Evaluation Report on the Adequacy of Station Electric Distribution System Voltages for the Turkey Point Nuclear Generating Plant, Units 3 and 4. Docket Nos. 50-250, 50-251.  

National Technical Information Service (NTIS)

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the Turkey Point Nuclear Generating Plant, Units 3 and 4. The evaluation is to determine if the onsite distribution system in conjuncti...

J. C. Selan

1982-01-01

320

HalleyVI - a station for science  

NASA Astrophysics Data System (ADS)

There has been a research station at Halley in Antarctica (75°35'S, 26°34'W) since 1956. Halley has a long and successful scientific record, notably the discovery of the Ozone Hole and significant contributions to areas as diverse as Geology and Space physics. Halley is located on a floating and flowing iceshelf with constant surface accumulation. These conditions have resulted in the necessary regular rebuilding of the station and HalleyVI has just been completed. Halley VI has been fully scientifically operational since Feb 2012. The station supports a chemical and turbulence clean area, an electromagnetic quiet zone, an area for radars, and flexible facilities on the station to support a wide variety of science activities. This presentation outlines the major features of the new station, its current scientific activities, and the facilities that allow the hosting of a wide variety of scientific experiments.

Rose, Mike; Tuplin, Karl

2013-04-01

321

Radar sensors for automotive collision warning and avoidance  

NASA Astrophysics Data System (ADS)

Many different sensors and systems, from sonar to machine vision, have been installed on ground vehicles and automobiles. This paper describes the use of radar to improve driving safety and convenience. Radars are valuable sensors for all weather operation and experiments with automotive radar sensors have been conducted for over 40 years. This paper shows the advantages and disadvantages of applying microwave and millimeter wave radar to obstacle detection and collision avoidance in a roadway environment. The performance differences between avoidance and warning sensors are discussed and a problem set is devised for a typical forward-looking collision warning application. Various radar systems have been applied to this problem that include pulse and continuous wave transceivers. These system types are evaluated as to their suitability as a collision warning sensor. The various possible solutions are reduced to a small number of candidate radar types, and one such radar was chosen for full scale development. A low cost frequency modulated/continuous wave radar system was developed for automotive collision warning. The radar is attached to the sun visor inside the vehicle, and has been in operation for over four years. The radar monitors the range and range-rate of other vehicles and obstacles, and warns the driver when it perceives that a dangerous situation is developing. A system description and measured data is presented that shows how the 24.075 to 24.175 GHz band can be used for an adequate early warning system.

Grosch, Theodore O.

1995-06-01

322

Local technicians in long-term research projects: evaluation of 25 years experience in an active tropical research station.  

PubMed

Most field ecology is conceived and financed by scientists from urban areas but is actually carried out in rural areas. Field staff can either be imported from urban areas or recruited from local residents. We evaluated the advantages and disadvantages of involving rural residents as local technicians over a 25- year period at active field research site in Costa Rica. We defined "local technicians" as local residents with no university education who acquired significant experience in field data collection, data management and/or laboratory work. We analyzed the experiences of incorporating these technicians into field research in developing countries from the points of view of scientist and of the local technicians themselves. Primary data were written responses from to a standardized survey of 19 senior scientists and Ph.D. students,and results from standardized personal interviews with 22 local technicians. Researchers highlighted the advantages of highly-skilled technicians with minimal staff turnover, as well as the technicians' knowledge of local ecological conditions. Local technicians considered the primary advantages of their jobs to be opportunities for continuing education training in science as well as cultural enrichment through interactions with people of different cultures. The main challenges identified by researchers were the lack of long-term funding for projects and extended training required for local technicians. Local technicians can be of great benefit to research projects by providing high-quality data collection at reasonable costs with low staff turnover. Over the last 25 years the research model at the field station we studied has evolved to the point that most long-term projects now depend heavily on local technicians. This model of involving local technicians in long-term research has multiple benefits for the researchers, the technicians and the local community, and could be adapted to a variety of settings in rural areas of developing countries. PMID:22208064

Hurtado, Johanna; Clark, David B

2011-12-01

323

Atmospheric Ionization Module Osnabrück (AIMOS): 3. Comparison of electron density simulations by AIMOS-HAMMONIA and incoherent scatter radar measurements  

NASA Astrophysics Data System (ADS)

Ionization of the atmosphere due to precipitating solar energetic particles as well as magnetospheric particles is a major source of thermospheric electron density. In this paper we evaluate numerical simulations of the 3-D spatial and temporal electron densities produced by these particle populations through a comparison with incoherent scatter radar observations. The 3-D precipitation patterns are determined with the Atmospheric Ionization Module Osnabrück (AIMOS). We use a version of the general circulation and chemistry model Hamburg Model of the Neutral and Ionized Atmosphere (HAMMONIA) enhanced by ion chemistry to calculate the impact of particle ionization on the electron density. These modeled data are compared to radar observations from European Incoherent Scatter Svalbard and Tromsø as well as the incoherent scatter radar stations at Millstone Hill and Sondrestrom. Particle precipitation is severely affected by geomagnetic disturbance and latitude. Therefore, different locations (inside the polar cap and at auroral latitudes) and geomagnetic conditions are included in the comparison. The main results of the paper can be summarized as follows: (1) as expected, particle forcing will significantly improve modeled electron density in comparison to results of the radar measurements; (2) in particular nighttime comparisons of the electron density are affected; here the particle forcing will account for a boost of 2 to 3 orders of magnitude.

Wissing, J. M.; Kallenrode, M.-B.; Kieser, J.; Schmidt, H.; Rietveld, M. T.; Strømme, A.; Erickson, P. J.

2011-08-01

324

Laser radar observation of the polar stratospheric aerosol layer  

NASA Astrophysics Data System (ADS)

The polar stratosphere has been speculated to be an active sink region of various stratospheric materials; ozone, water vapor, NOX, aerosol particles and so on, but this process is not theoretically and/or observationally made clear. The observation of the polar stratospheric aerosol layer using laser radar certainly contributes to the study of the global transport of these stratospheric minor constituents. In addition to this, from the viewpoint of aerosol science, there may be many interesting phenomena which cannot be found in the stratosphere at mid and low latitudes; the effect of precipitation of high energy molecules and atoms, of very cold winter stratosphere, of very cold mesopause in summer. Laser radar observation is one of the main activities of the Antarctic Middle Atmosphere (AMA) project at Syowa Station (69.00 deg S, 39.35 deg E), Antarctica since May 1983. Laser radar measurement at Syowa Station is discussed in detail.

Iwasaka, Y.; Hirasawa, T.; Fukunishi, H.; Fujiwara, M.; Fujii, R.; Miyaoka, H.

1985-12-01

325

RADARC HF ionospheric prediction program for OTH radar  

NASA Astrophysics Data System (ADS)

A model for predicting the performance of an over-the-horizon high frequency (HF) radar is described. The program can also be used for management of an existing radar or for HF broadcasting assessment. When the radar parameters, such as power, antenna, and frequency are given, the program predicts the signal-to-noise, ground clutter-to-noise, ionospheric spread Doppler clutter-to-noise, and received power as a function of range from the radar site. The report is intended to provide the reader with a general description of the prediction model and to show those mathematics and procedures which are upgraded from NRL Report 2226. The procedures should provide the OTH radar engineers with information to execute the program for studies or evaluation of existing or planned radars.

Lucas, D. L.; Prinson, G. S.; Headrick, J. M.; Thomason, J. F.

1993-09-01

326

Terrain Classification in Central Navarre (Spain) Using Polarimetric Radar Images  

NASA Astrophysics Data System (ADS)

Traditionally in Navarre, studies concerning remote sensing techniques have been carried out using optical sensor data. However, cloud cover frequently hampers the acquisition of optical data, causing limitations in its use. Radar sensors are not affected by clouds and, apart from that, the new generation of space-borne radar sensors available offer new capabilities such as the ability to operate with multiple polarizations simultaneously, acquiring polarimetric observations. The main objective of this study is to evaluate the feasibility of polarimetric radar observations for terrain classification in central Navarre. The use of radar images in Navarre is something new because until now these images only have been used to do doctoral thesis.

Larrañaga, A.; Álvarez-Mozos, J.; Albizua, L.; Barinagarrementeria, I.

2009-04-01

327

Dynamic Performance of a Landing Radar BBM in Field Experiments  

NASA Astrophysics Data System (ADS)

The Institute of Space and Astronautical Science JAXA is developing a landing radar comprising a radio altimeter and a velocity meter, which are two of the mandatory navigation sensors for a planetary lander. The landing radar employs a pulse-type radar using 4.3GHz C-band microwave radiation. It has a wide beam for measuring the altitude in vertical direction, as well as four narrow tilted beams for measuring the velocity in horizontal direction. A BBM of the landing radar has been evaluated on natural terrains by using a helicopter. This paper introduces the BBM hardware and discusses the dynamic performance in field experiments.

Mizuno, Takahide; Fukuda, Seisuke; Sakai, Tomohiko; Okada, Yu; Sato, Teppei; Kishimoto, Kenji

328

Evaluation of human exposure in the vicinity of a base-station antenna using the multiple-region\\/FDTD hybrid method  

Microsoft Academic Search

In this paper, human exposure to the electromagnetic field radiated from a GSM radio-base station antenna operating in the 900-MHz frequency band has been analyzed. A hybrid multiple-region\\/FDTD method has been used to evaluate the field radiated by the antenna and the power absorbed in an accurate model of the exposed subject. The results show that field levels averaged on

Paolo Bernardi; Marta Cavagnaro; Stefmo Pisa; Emanuele Piuzzi

2002-01-01

329

Evaluation of the Submerged Demineralizer System (SDS) flowsheet for decontamination of high-activity-level water at the Three Mile Island Unit 2 Nuclear Power Station  

SciTech Connect

This report discusses the Submerged Demineralizer System (SDS) flowsheet for decontamination of the high-activity-level water at the Three Mile Island Unit 2 Nuclear Power Station was evaluated at Oak Ridge National Laboratory in a study that included filtration tests, ion exchange column tests, and ion exchange distribution tests. The contaminated waters, the SDS flowsheet, and the experiments made are described. The experimental results were used to predict the SDS performance and to indicate potential improvements.

Campbell, D.O., Collins, E.D., King, L.J., Knauer, J.B.

1980-07-01

330

A microwave radio for Doppler radar sensing of vital signs  

Microsoft Academic Search

A microwave radio for Doppler radar sensing of vital signs is described. This radio was developed using custom DCS1800\\/PCS1900 base station RFICs. It transmits a single tone signal, demodulates the reflected signal, and outputs a baseband signal. If the object that reflects the signal has periodic motion, the magnitude of the baseband output signal is directly proportional to the periodic

Amy Droitcour; Victor Lubecke; Jenshan Lin; Olga Boric-Lubecke

2001-01-01

331

78. View of radar systems technical publication library, transmitter building ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

78. View of radar systems technical publication library, transmitter building no. 102, second floor. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

332

10. View of back side of radar scanner building no. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. View of back side of radar scanner building no. 104 showing passageway links to other building to east and DR 1 antenna in background. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

333

37. View of detection radar environmental display (DRED) console for ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

37. View of detection radar environmental display (DRED) console for middle DR 2 (structure no. 736) antenna, located in MWOC facility. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

334

9. View of back side of radar scanner building no. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. View of back side of radar scanner building no. 106 showing passageway links to other buildings east and west, and DR 3 antenna in background. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

335

23. View of junction of passageway link with radar transmitter ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

23. View of junction of passageway link with radar transmitter building 102 (view looking south) showing main personnel entrance door. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

336

74. Transmitter building no. 102, view of radar digital test ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

74. Transmitter building no. 102, view of radar digital test and maintenance cabinet area control panel and date storage system showing ampex tape storage devices. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

337

The Detection of Bird Migration by High-Power Radar  

Microsoft Academic Search

The new and more powerful R.A.F. 10 cm radar sets frequently detect 'angels' to ranges exceeding 60 miles from the station. The seasons and times of day of their occurrence, their speed in relation to the wind, their directions of movement, and the influence of the weather, all fit the view that such echoes come from migrating birds, especially passerine

J. G. Tedd; D. Lack

1958-01-01

338

Evaluation of station blackout accidents at nuclear power plants: Technical findings related to unresolved safety issue A-44: Final report  

SciTech Connect

''Station Blackout,'' which is the complete loss of alternating current (AC) electrical power in a nuclear power plant, has been designated as Unresolved Safety Issue A-44. Because many safety systems required for reactor core decay heat removal and containment heat removal depend on AC power, the consequences of a station blackout could be severe. This report documents the findings of technical studies performed as part of the program to resolve this issue. The important factors analyzed include: the fequency of loss of offsite power; the probability that emergency or onsite AC power supplies would be unavailable; the capability and reliability of decay heat removal systems independent of AC power; and the likelihood that offsite power would be restored before systems that cannot operate for extended periods without AC power fail, thus resulting in core damage. This report also addresses effects of different designs, locations, and operational features on the estimated frequency of core damage resulting from station blackout events.

Not Available

1988-06-01

339

EISCAT Svalbard radar  

Microsoft Academic Search

The main fields of interest of the Finnish scientists in EISCAT research are listed. Finnish interests in the Polar Cap Radar (PMR) and areas where the Finnish contribution could be important are addressed: radar techniques; sporadic E layers in the polar cap; atmospheric models; auroral studies in the polar cap; nonthermal plasmas in the F region; coordinated measurements with the

Markku Lehtinen; Jorma Kangas

1992-01-01

340

EISCAT Svalbard Radar.  

National Technical Information Service (NTIS)

The main fields of interest of the Finnish scientists in EISCAT research are listed. Finnish interests in the Polar Cap Radar (PMR) and areas where the Finnish contribution could be important are addressed: radar techniques; sporadic E layers in the polar...

M. Lehtinen J. Kangas

1992-01-01

341

Radar illusion via metamaterials  

NASA Astrophysics Data System (ADS)

An optical illusion is an image of a real target perceived by the eye that is deceptive or misleading due to a physiological illusion or a specific visual trick. The recently developed metamaterials provide efficient approaches to generate a perfect optical illusion. However, all existing research on metamaterial illusions has been limited to theory and numerical simulations. Here, we propose the concept of a radar illusion, which can make the electromagnetic (EM) image of a target gathered by radar look like a different target, and we realize a radar illusion device experimentally to change the radar image of a metallic target into a dielectric target with predesigned size and material parameters. It is well known that the radar signatures of metallic and dielectric objects are significantly different. However, when a metallic target is enclosed by the proposed illusion device, its EM scattering characteristics will be identical to that of a predesigned dielectric object under the illumination of radar waves. Such an illusion device will confuse the radar, and hence the real EM properties of the metallic target cannot be perceived. We designed and fabricated the radar illusion device using artificial metamaterials in the microwave frequency, and good illusion performances are observed in the experimental results.

Jiang, Wei Xiang; Cui, Tie Jun

2011-02-01

342

Doppler weather radar  

Microsoft Academic Search

The Doppler weather radar and its signals are examined from elementary considerations to show the origin and development of useful weather echo properties such as signal-to-noise ratio (SNR), range correlation, signal statistics, etc. We present a form of the weather radar equation which explicitly shows the echo power loss due to finite receiver bandwidth and how it is related to

RICHARD J. DOVIAK; DUSAN S. ZRNIC; DALE S. SIRMANS

1979-01-01

343

Advances in Radar Techniques  

NASA Astrophysics Data System (ADS)

Most of the clutter received by L, S, C, X, and Ku band radars obeys a Weibull ditribution. To suppress such Weibull-distributed sea and weather clutter, Weibull CFAR techniques are applied to data taken by an X-band radar using computer in real time. The results show the usefulness of Weibull CFAR.

Sekine, Matsuo

344

UWB radars in medicine  

Microsoft Academic Search

Applied research on biomedical applications of UWB radar is targeted to the identification of the possible new devices made possible by the technology, to the design and development of those devices, and to the clinical testing of the systems obtained. Applications can be divided into two main sectors according to the frequency range used. For the conventional UWB radar microwave

Enrico M. Staderini

2002-01-01

345

Stereo Radar Analysis.  

National Technical Information Service (NTIS)

The topographic accuracy of the AN/APQ-102(XA-2) side-looking radar and its specific applicability to 1:50,000 and 1:250,000 scale topographic mapping were tested using stereo radar techniques with real data. The two basic stereo configurations, opposite-...

G. Gracie R. K. Brewer J. W. Bricker R. A. Johnson

1970-01-01

346

Panchromatic and polypanchromatic radar  

Microsoft Academic Search

Application of broad-band (panchromatic) illumination in radar systems should permit improvement in image quality and reduction of tracking and detection problems due to fading. The effect of frequency averaging on radar return from a simple target array is demonstrated by numerical computation and on image quality by ultrasonic simulation. The required bandwidth for a slightly rough random surface is determined

RICHARD K. MOORE; WILLIAM P. WAITE

1969-01-01

347

Radar clutter classification  

Microsoft Academic Search

The problem of classifying radar clutter as found on air traffic control radar systems is studied, and an algorithm is developed to carry out this classification automatically. The basis for the algorithm is Bayes decision theory and the parametric maximum a posteriori probability (MAP) classifier. This classifier employs a quadratic discriminant function and is optimum for feature vectors that are

Wolfgang Stehwien

1990-01-01

348

Radar clutter classification  

Microsoft Academic Search

The problem of classifying radar clutter as found on air traffic control radar systems is studied. An algorithm based on Bayes decision theory and the parametric maximum a posteriori probability classifier is developed to perform this classification automatically. This classifier employs a quadratic discriminant function and is optimum for feature vectors that are distributed according to the multivariate normal density.

Wolfgang Stehwien

1989-01-01

349

On radar polarimetry in FM-CW radar  

Microsoft Academic Search

This paper attempts to apply the principle of radar polarimetry to wideband synthetic aperture FM-CW radar and presents a basic polarimetric detection result of a linear target in a laboratory measurement. Although the principle of radar polarimetry has well been established for the completely polarized wave and for the monostatic case, it still needs to be extended to wideband radar

Y. Yamaguchi; T. Nishikawa; W.-M. Boerner; M. Sengoku; Hyo Joon Eom

1993-01-01

350

Radar Location Equipment Development Program: Phase I  

SciTech Connect

The work described in this report represents the first phase of a planned three-phase project designed to develop a radar system for monitoring waste canisters stored in a thick layer of bedded salt at the Waste Isolation Pilot Plant near Carlsbad, New Mexico. The canisters will be contained in holes drilled into the floor of the underground waste storage facility. It is hoped that these measurements can be made to accuracies of +-5 cm and +-2/sup 0/, respectively. The initial phase of this project was primarily a feasibility study. Its principal objective was to evaluate the potential effectiveness of the radar method in the planned canister monitoring application. Its scope included an investigation of the characteristics of radar signals backscattered from waste canisters, a test of preliminary data analysis methods, an assessment of the effects of salt and bentonite (a proposed backfill material) on the propagation of the radar signals, and a review of current ground-penetrating radar technology. A laboratory experiment was performed in which radar signals were backscattered from simulated waste canisters. The radar data were recorded by a digital data acquisition system and were subsequently analyzed by three different computer-based methods to extract estimates of canister location and tilt. Each of these methods yielded results that were accurate within a few centimeters in canister location and within 1/sup 0/ in canister tilt. Measurements were also made to determine the signal propagation velocities in salt and bentonite (actually a bentonite/sand mixture) and to estimate the signal attenuation rate in the bentonite. Finally, a product survey and a literature search were made to identify available ground-penetrating radar systems and alternative antenna designs that may be particularly suitable for this unique application. 10 refs., 21 figs., 4 tabs.

Sandness, G.A.; Davis, K.C.

1985-06-01

351

Design and Evaluation of a Backhaul-Aware Base Station Assignment Algorithm for OFDMA-Based Cellular Networks  

Microsoft Academic Search

Existing base station (BS) assignment methods in cellular networks are mainly driven by radio criteria since it is assumed that the only limiting resource factor is on the air interface. However, as enhanced air interfaces have been deployed, and mobile data and multimedia traffic increases, a growing concern is that the backhaul of the cellular network can become the bottleneck

Hiram Galeana-Zapién; Ramon Ferrús

2010-01-01

352

Analysis of Incoming Wave Distribution in Vertical Plane in Urban Area and Evaluation of Base Station Antenna Effective Gain  

Microsoft Academic Search

In order to reduce the amount of interference to neighboring cells in cellular systems, we generally use base station (BS) antennas that have sharp beam patterns in the vertical plane; however, the distribution of incoming waves at the BS affects the effective gain of the BS antennas which have directional pattern. Therefore, we have to clarify the characteristics of the

Koshiro Kitao; Tetsuro Imai

2009-01-01

353

Fatality Assessment and Control Evaluation (FACE) Report: Fire Fighter Suffers Sudden Cardiac Death at His Fire Station in Georgia.  

National Technical Information Service (NTIS)

On June 17, 2004, a 47-year-old male firefighter (FF) suffered cardiac dysrhythmia and was found pulseless and apneic shortly after 1900 hours while on duty at his fire station. Despite ALS treatment at the scene, en route, and at the hospital, the FF was...

2005-01-01

354

Evaluation of C. P. Crane Generating Station thermal discharge effects on the finfish community, summer 1980. Final report  

SciTech Connect

The objective of this study was to verify if patterns of abundance observed during Summer, 1980 reflected response to the thermal discharge of the power plant or if they might be attributed to other factors. Fish were collected by both trawling and gill nets at seven stations. Results indicated that the patterns previously attributed to thermal effects may be better explained by habitat preference.

Not Available

1981-01-01

355

Fatality Assessment and Control Evaluation (FACE) Report: Fire Fighter Suffers Sudden Cardiac Death at His Fire Station in Oregon.  

National Technical Information Service (NTIS)

On February 20, 2003, at 0730 hours, a 53-year- old male career Captain (the deceased) began his 24-hour shift at his fire station. During his shift, the Captain was performing normal duties including checking fire extinguishers and participating in train...

2003-01-01

356

An evaluation of the effects of local control station design configurations on human performance and nuclear power plant risk  

Microsoft Academic Search

A human factors analysis was performed to assess how identified upgrades to local control stations (LCSs) in nuclear power plants affect both human performance and plant risk. Upgrades in the design of individual control panels and overall improvement of functional centralization were considered. The analysis methodology was accomplished in four stages. First, a list of LCS human engineering design deficiencies

J. OHara; C. Ruger; J. Higgins; W. Luckas; D. Crouch

1990-01-01

357

Air traffic control radar tester  

Microsoft Academic Search

Our aim is to develop a radar tester equipment for commercial and military services. The task is to create one (or more) target or clutter on the radar screen with given distance, velocity and fluctuation. This equipment is placed within few hundred meters from the radar, so it is able to analyze the whole radar system from the antenna, via

Péter KOVÁCS; Levente DUDÁS; Rudolf SELLER; József ORBÁN

2008-01-01

358

Air traffic control radar tester  

Microsoft Academic Search

Our aim had been to develop a radar tester equipment for commercial and military services. The task is to create one (or more) target or clutter on the radar screen with given distance, velocity and fluctuation. This equipment is placed within few hundred meters from the radar, so it is able to analyze the whole radar system from the antenna,

Levente DUDÁS; Rudolf SELLER; Péter RENNER; József ORBÁN

2009-01-01

359

Application of HF radar currents to oil spill modelling  

Microsoft Academic Search

In this work, the benefits of high-frequency (HF) radar currents for oil spill modeling and trajectory analysis of floating objects are analyzed. The HF radar performance is evaluated by means of comparison between a drifter buoy trajectory and the one simulated using a Lagrangian trajectory model. A methodology to optimize the transport model performance and to calculate the search area

Ana J. Abascal; Sonia Castanedo; Raul Medina; Inigo J. Losada; Enrique Alvarez-Fanjul

2009-01-01

360

Coordinate Conversion and Tracking for Very Long Range Radars  

Microsoft Academic Search

The problem of tracking with very long range radars is studied in this paper. First, the measurement conversion from a radar's r-u-v coordinate system to the Cartesian coordinate system is discussed. Although the nonlinearity of this coordinate transformation appears insignificant based on the evaluation of the bias of the converted measurements, it is shown that this nonlinearity can cause significant

X. Tian; Y. Bar-Shalom

2009-01-01

361

Integrated mobile radar-camera system in airport perimeter security  

Microsoft Academic Search

The paper presents the test results of a mobile system for the protection of large-area objects, which consists of a radar and thermal and visual cameras. Radar is used for early detection and localization of an intruder and the cameras with narrow field of view are used for identification and tracking of a moving object. The range evaluation of an

M. Zyczkowski; M. Szustakowski; W. Ciurapinski; R. Dulski; M. Kastek; P. Trzaskawka

2011-01-01

362

Experimental study on human being detection using UWB radar  

Microsoft Academic Search

In this paper we are evaluating the feasibility of using an UWB radar as a victim search device in emergency situations. The idea of human being detection using UWB radar is to observe periodic differences in time-of-arrival of scattered pulses from the victim, which are result of periodic movements of the chest area of the victim. This motion cannot be

Amer Nezirovic; Alexander G. Yarovoy; Leo P. Ligthart

2006-01-01

363

Polar mesosphere summer radar echoes: Observations and current theories  

Microsoft Academic Search

In the present article the authors review observations and proposed theories of the strong radar echoes originating from the summer polar mesosphere. The progress that has been made toward understanding this phenomenon is evaluated. The connections of the radar echoes to global climate change, to [open quotes]dusty plasma[close quotes], and to the highest clouds of the atmosphere are discussed. Suggestions

John Y. N. Cho; Michael C. Kelley

1993-01-01

364

A Doppler Radar Emulator with an Application to the Detectability of Tornadic Signatures  

Microsoft Academic Search

A Doppler radar emulator was developed to simulate the expected mean returns from scanning radar, including pulse-to-pulse variability associated with changes in viewing angle and atmospheric structure. Based on the user's configuration, the emulator samples the numerical simulation output to produce simulated returned power, equivalent radar reflectivity, Doppler velocity, and Doppler spectrum width. The emulator is used to evaluate the

Ryan M. May; Michael I. Biggerstaff; Ming Xue

2007-01-01

365

A Single-Radar Technique for Estimating the Winds in Tropical Cyclones  

Microsoft Academic Search

A method for determining horizontal wind speeds in hurricanes using ground-based radars is presented and evaluated. The method makes use of the tracking reflectivity echos by correlation (TREC) method where individual features in radar reflectivity are tracked, from radar sweeps several minutes apart, by finding the maxima in the cross-correlation function between the two times. This method has been applied

John Tuttle; Robert Gall

1999-01-01

366

A modeling method of radar seeker in the presence of electronic warfare  

Microsoft Academic Search

Due to the requirements of evaluating the performance of the radar seeker in the combat conditions or in the presence of electronic warfare, this paper gives a design of A Sensitive and Generalization Modeling of The Radar Seeker simulation system, and describes its Modularization, Parameterization, Interface support, Sensitivity Analysis Support design method, a pulse Doppler radar seeker based simulation system

Cao Yuan; Li Yunjie; Hu Guangli; Liu Yong; Ma Xiao

2010-01-01

367

Assessment of variability in continental low stratiform clouds based on observations of radar reflectivity  

Microsoft Academic Search

The variability of overcast low stratiform clouds observed over the ARM Climate Research Facility Southern Great Plains (ACRF SGP) site is analyzed, and an approach to characterizing subgrid variability based on assumed statistical distributions is evaluated. The analysis is based on a vast (>1000 hours) radar reflectivity database collected by the Millimeter-Wave Cloud Radar at ACRF SGP site. The radar

Zena N. Kogan; David B. Mechem; Yefim L. Kogan

2005-01-01

368

A multi-agent system for meteorological radar data management and decision support  

Microsoft Academic Search

* Abstract: The Meteorological Service of Cyprus operates a Doppler radar at the mountainous region of the island. Data-streams recorded by the radar are used for weather forecasting and, especially, for identifying oncoming precipitation incidents and issuing (potential) warnings. However, the continuous processing and evaluation of radar data requires significant efforts by the meteorologists, both for data processing, storage, and

Ioannis N. Athanasiadis; Marios Milis; Pericles A. Mitkas; Silas C. Michaelides

2009-01-01

369

AN AUTOMATED METHOD FOR DETECTING PRECIPITATION AND CELL TYPE FROM RADAR PRODUCTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

It is of interest for many purposes, including nowcasting, to evaluate the structure of radar images in an effort to produce more accurate estimates of rainfall totals from radar data. Although subjective analysis can reliably determine the structure of radar imagery, computational techniques exist ...

370

Low-frequency ultra-wideband synthetic aperture radar 1995 BoomSAR tests  

Microsoft Academic Search

The Army Research Laboratory has been investigating the potential of ultra-wideband synthetic aperture radar (UWB SAR) technology to detect and classify targets embedded in foliage or in the ground. The UWB foliage penetration (FOPEN) radar program has been extended to include the evaluation of ground penetration (GPEN) radar technology. ARL is investigating these problems by collecting high quality, precision data

Lynn Happ; Karl A. Kappra; Marc A. Ressler; Jeffrey P. Sichina; Keith Sturgess; Francis Le

1996-01-01

371

Technical evaluation of the adequacy of station electric-distribution-system voltages for the St. Lucie Nuclear Power Plant, Unit 1  

SciTech Connect

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the St. Lucie Nuclear Power Plant, Unit 1. The evaluation is to determine if the onsite distribution system, in conjunction with the offsite power sources, has sufficient capacity to automatically start and operate all Class 1E loads within the equipment voltage ratings under certain conditions established by the Nuclear Regulatory Commission. The voltage analysis submitted has adequately demonstrated the capacity and capability of the electrical distribution system to supply adequate voltage to the Class 1E equipment under worst case operating conditions.

Selan, J.C.

1981-10-05

372

Evaluation of Matched Filters and the Three-Component Adaptive processor for the VLPE Stations and VLPE Network. Technical Report No. 5. VELA Network Evaluation and Automatic Processing Research.  

National Technical Information Service (NTIS)

The report describes the evaluation of the chirp matched filter, the reference waveform matched filter, and the three-component adaptive processor in terms of events from two seismic regions and one presumed explosion test region as recorded by stations o...

A. C. Strauss A. I. Tolstoy

1974-01-01

373

Air Shower Detection by Bistatic Radar  

NASA Astrophysics Data System (ADS)

Progress in the field of high-energy cosmic rays is currently limited by the rarity of the most interesting rays striking the Earth. Indeed, the continuation of the field beyond the current generation of observatories may become financially and practically impossible if new ways are not found to achieve remote coverage over large portions of the Earth's surface. We describe the development of an observatory based on such a new technique: the remote sensing via bistatic radar technology of cosmic ray induced extensive air showers. We build on pilot studies performed by MARIACHI which have demonstrated that air shower radar echoes are detectable, the opportunity afforded by the location of the Northern Hemisphere's largest ``conventional'' cosmic ray observatory (The Telescope Array) in radio-quiet western Utah, and the donation of analog television transmission equipment to this effort by a local television station.

Othman, M. Abou Bakr; Allen, C.; Belz, J.; Besson, D.; Farhang-Boroujeny, B.; Ikeda, D.; Kunwar, S.; Lundquist, J. P.; Kravchenko, I.; Myers, I.; Nakamura, T.; Sagawa, H.; Sokolsky, P.; Takai, H.; Terasawa, T.; Thomson, G. B.

2011-09-01

374

Rendezvous radar for the orbital maneuvering vehicle  

NASA Astrophysics Data System (ADS)

The Rendezvous Radar Set (RRS) was designed at Motorola's Strategic Electronics Division in Chandler, Arizona, to be a key subsystem aboard NASA's Orbital Maneuvering Vehicle (OMV). The unmanned OMV, which was under development at TRW's Federal Systems Division in Redondo Beach, California, was designed to supplement the Shuttle's satellite delivery, retrieval, and maneuvering activities. The RRS was to be used to locate and then provide the OMV with vectoring information to the target satellite (or Shuttle or Space Station) to aid the OMV in making a minimum fuel consumption approach and rendezvous. The OMV development program was halted by NASA in 1990 just as parts were being ordered for the RRS engineering model. The paper presented describes the RRS design and then discusses new technologies, either under development or planned for development at Motorola, that can be applied to radar or alternative sensor solutions for the Automated Rendezvous and Capture problem.

Locke, John W.; Olds, Keith A.; Quaid, Thomas

375

Health Hazard Evaluation Report: HETA-2007-0055-3073, Huntington Coach Corporation, Huntington Station, New York, October 2008. Evaluation of Employee Exposures in a Bus Maintenance Shop.  

National Technical Information Service (NTIS)

NIOSH received a confidential employee request for an HHE at the Huntington Coach Corporation bus repair and body shops, Huntington Station, New York, in November 2006. Employees were concerned that exposures to cleaning solvents, paint vapors, diesel exh...

A. Sussell L. Tapp

2008-01-01

376

Cassini radar : system concept and simulation results  

NASA Astrophysics Data System (ADS)

The Cassini mission is an international venture, involving NASA, the European Space Agency (ESA) and the Italian Space Agency (ASI), for the investigation of the Saturn system and, in particular, Titan. The Cassini radar will be able to see through Titan's thick, optically opaque atmosphere, allowing us to better understand the composition and the morphology of its surface, but the interpretation of the results, due to the complex interplay of many different factors determining the radar echo, will not be possible without an extensive modellization of the radar system functioning and of the surface reflectivity. In this paper, a simulator of the multimode Cassini radar will be described, after a brief review of our current knowledge of Titan and a discussion of the contribution of the Cassini radar in answering to currently open questions. Finally, the results of the simulator will be discussed. The simulator has been implemented on a RISC 6000 computer by considering only the active modes of operation, that is altimeter and synthetic aperture radar. In the instrument simulation, strict reference has been made to the present planned sequence of observations and to the radar settings, including burst and single pulse duration, pulse bandwidth, pulse repetition frequency and all other parameters which may be changed, and possibly optimized, according to the operative mode. The observed surfaces are simulated by a facet model, allowing the generation of surfaces with Gaussian or non-Gaussian roughness statistic, together with the possibility of assigning to the surface an average behaviour which can represent, for instance, a flat surface or a crater. The results of the simulation will be discussed, in order to check the analytical evaluations of the models of the average received echoes and of the attainable performances. In conclusion, the simulation results should allow the validation of the theoretical evaluations of the capabilities of microwave instruments, when considering topics like the surface topography, stratigraphy and identification of different materials.

Melacci, P. T.; Orosei, R.; Picardi, G.; Seu, R.

1998-10-01

377

Radar applications overview  

NASA Astrophysics Data System (ADS)

During the fifty years since its initial development as a means of providing early warning of airborne attacks against allied countries during World War II, radar systems have developed to the point of being highly mobile and versatile systems capable of supporting a wide variety of remote sensing applications. Instead of being tied to stationary land-based sites, radar systems have found their way into highly mobile land vehicles as well as into aircraft, missiles, and ships of all sizes. Of all these applications, however, the most exciting revolution has occurred in the airborne platform arena where advanced technology radars can be found in all shapes and sizes...ranging from the large AWACS and Joint STARS long range surveillance and targeting systems to small millimeter wave multi-spectral sensors on smart weapons that can detect and identify their targets through the use of highly sophisticated digital signal processing hardware and software. This paper presents an overview of these radar applications with the emphasis on modern airborne sensors that span the RF spectrum. It will identify and describe the factors that influence the parameters of low frequency and ultra wide band radars designed to penetrate ground and dense foliage environments and locate within them buried mines, enemy armor, and other concealed or camouflaged weapons of war. It will similarly examine the factors that lead to the development of airborne radar systems that support long range extended endurance airborne surveillance platforms designed to detect and precision-located both small high speed airborne threats as well as highly mobile time critical moving and stationary surface vehicles. The mission needs and associated radar design impacts will be contrasted with those of radar systems designed for high maneuverability rapid acquisition tactical strike warfare platforms, and shorter range cued air-to-surface weapons with integral smart radar sensors.

Greenspan, Marshall

1996-06-01

378

Incoherent scatter radar contributions  

NASA Astrophysics Data System (ADS)

The contributions of the incoherent scatter radar technique to knowledge of the neutral upper atmosphere of the earth in general and the development of the CIRA 1986 model in particular are discussed. Incoherent radar scattering involves the transmission of a radio wave into the atmosphere and the reception of the energy scattered by the free electrons illuminated by the wave. Attention is given to the chronology of radar contributions to the development of upper atmosphere models, the ion energy balance and continuity equations, exospheric temperatures, and studies of the lower thermosphere.

Oliver, W. L.; Alcayde, D.; Bauer, P.

379

Active radar jamming  

NASA Astrophysics Data System (ADS)

Active radar jammers are described. In confusion jammers the perturbing action is produced by thermal noise which is intensified, or by a carrier wave modulated by a noise signal, or by a carrier wave which is frequency modulated with a lot of sine waves of different frequencies. There are jammers to be used once, which are fired to the spot or hang from a parachute. Deception jammers (misleading jammers) emit false radar echoes, one or several produced by a repetition system, requiring a certain form of memory. It is shown how to emit varying false distance or velocities, and how to disturb angles in a radar used to guide artillery fire.

Jernemalm, Veine

1988-09-01

380

Comparison of Ambient Noise From Two Station Designs, Evaluating USArray's Transportable and Flexible Arrays in the Pacific Northwest  

NASA Astrophysics Data System (ADS)

The USArray program within the National Science Foundation-funded Earthscope program is comprised of two portable broadband seismic projects; the Transportable Array (TA), and the Flexible Array (FA). The TA consists of 400 stations occupy locations within the United States on a nominal 70 km spacing for a period of approximately 24 months. As a network, these TA stations roll from west to east so that within 10 years the entire lower 48 states will have been occupied by the TA network. As a complementary component of USArray, the FA pool of instruments is comprised of 1200 active-source, 120 short-period and 326 broadband portable stations. These instruments are used by Principal Investigator-driven studies which focus on geologic targets within the TA footprint. Currently the TA network is transitioning from the Rocky Mountains into the Great Plains. The FA currently has four experiments installed. In this study we quantify the overall performance of these two tandem networks using a controlled set of continuous recordings in Western Washington. We compare the background noise levels between the standard deep TA and shallow FA broadband sensor vault system. We use McNamara’s probability density function (PDF) analysis as the basis of the comparison. We combine the network wide PDF’s of each network for a period of over 600 days of contemporaneous recordings. Preliminary analysis using data from 28 TA stations in western Washington and 47 nearby FA stations from the CAFE experiment (Abers, et al. Eos Trans. AGU 88(52), Fall Meet. Suppl. S43D-07), show that the TA stations are quieter at periods below 20 seconds by about 12 dB on the horizontal components. The vertical components for both the TA and FA are equivalent for periods below 5 seconds. At higher frequencies (> 2 Hz), however, the FA shallower vault is quieter by approximately 10 dB on both the vertical and horizontal components. The question addressed is, what is contributing to the difference in ambient noise level? Both vault systems are designed to minimize noise from either cultural, electronic or environmental sources. In the case for the TA vault, a 2 meter deep hole is dug using heavy excavation equipment with over a square meter of concrete used for a base and Earth coupling. A deeper vault is known to reduce the diurnal temperature fluctuations that are a major source of noise for the broadband sensor. The standard FA vault is typically less than 1 meter deep dug by hand with approximately 1/10 square meter of concrete as a base. The construction materials and the seismic equipment for both these vaults are otherwise equivalent. We propose the following explanation for the difference in noise levels as a function of frequency and sensor component. The deeper TA vault is more stable with respect tilt which reduces the diurnal and seasonal temperature changes resulting in quieter horizontal data. The general location of TA stations near cultural noise sources such as roadways and population centers contribute to the elevated high frequency noise as compared to FA stations that are often located in very remote locations.

Pfeifer, M.; Alvarez, M.; Woodward, R.; Yang, Z.

2009-12-01

381

Health hazard evaluation report HETA 93-1062-2558, Texas Utilities Electric Company, Martin Lake Steam Electric Station, Tatum, Texas  

SciTech Connect

In response to a request from workers at the Texas Utilities Electric Company (SIC-4911), Martin Lake Steam Electric Station in Tatum, Texas, the incidence of neurologic symptoms and exposure to electromagnetic fields and organophosphates were investigated. Workers reported neurological symptoms, including memory loss, dizziness and fatigue. A site visit to the station revealed electromagnetic field levels below the current occupational standard of 10 gauss. The use of an organophosphate containing fire resistant hydraulic fluid, Fyrquel-EH (1330785), was reported by employees. A significant correlation was identified between memory of past symptoms indicative of acute organophosphate exposure after working with Fyrquel-EH and current symptoms; however, blood cholinesterase levels were all within the normal range and no relevant neurologic abnormalities were noted on neurological examinations. The authors conclude that a hazard existed from the use of Fyrquel-EH. The authors recommend measures for the safe handling of organophosphate compounds.

Malkin, R.; Moss, C.E.; Reh, C.M.; Ragab, M.

1996-01-01

382

Evaluation of R. Paul Smith Steam Electric Station thermal discharge effects on benthic communities; Spring 1980. Final report  

SciTech Connect

A study of thermal effluent effects on benthic invertebrates was conducted near the R.P. Smith Steam Electric Station. Samples were collected during May 1980 with a dome suction sampler and an aquatic drift net. Samples were collected on upstream and downstream control transects and on transects in the thermally influenced area. The objective of this survey was to assess effects of thermal discharge on the abundance and biomass macroinvertebrates in the Potomac River.

Not Available

1980-09-01

383

Technical Evaluation of the Proposed Design Modifications and Technical Specification Changes on Grid Voltage Degradation (Part A) for the Peach Bottom Atomic Power Station, Units 2 and 3: Selected Issues Program (Docket Nos. 50-277, 50-278).  

National Technical Information Service (NTIS)

This report documents the technical evaluation of the proposed design modification and Technical Specification changes for protection of Class 1E equipment from grid voltage degradation for the Peach Bottom Atomic Power Station, Units 2 and 3. The review ...

R. L. White

1981-01-01

384

An Evaluation of the Observational Capabilities of A Scanning 95-GHz Radar in Studying the 3D Structures of Marine Stratocumulus Clouds  

NASA Astrophysics Data System (ADS)

Marine stratocumulus clouds play a critical role in Earth's radiative balance primarily due to the role of their high albedo reflecting incoming solar radiation, causing a cooling effect, while weakly reflecting outgoing infrared radiation. Characterization of the 3-Dimensional (3D) structure of these cloud systems over scales of 20-40 km is required to accurately account for the role of cloud inhomogeneity and structure on their shortwave forcing and lifetime, which has important applications for Global Climate Models. For first time, such 3D measurements in clouds were made available from a scanning cloud radar during the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) program's Clouds, Aerosol, and Precipitation in the Marine Boundary Layer (CAP-MBL) field campaign in the Azores Islands. The scanning radar observations were complemented by a suite of zenith-pointing active and passive remote sensors that were deployed to provide a detailed description of marine stratus over a long-term observation period in the ideal marine environment commonly found at the Azores. The scanning cloud radar observations present a shift from a multi-instrument, vertically pointing 'soda-straw' observation technique to a radar-only, 'radar-centric' observation technique. The scanning radar observations were gridded using a nearest-neighbor type scheme devised to take the natural variability of the observed field into account. The ability of the scheme to capture primary cloud properties (cloud fraction, cloud boundaries, drizzle detection) was assessed using measurements from the vertically pointing sensors. Despite the great sensitivity of the scanning cloud radar (-42.5 dBZ at 1 km range), the drop in sensitivity with range resulted in an artificial thinning of clouds with range from the radar. Drizzle-free cloud structures were undetectable beyond 5 km from the radar. Cloud fields containing drizzle were generally detectable to ranges exceeding 10 km from the radar. Well-defined streaking patterns in the drizzle field (reflectivity greater than -15 dBZ) at cloud base were concluded to be concomitant with the formation of boundary layer rolls. Sounding data for these well-defined (unbroken) rolls revealed a mean sub-cloud layer wind exceeding 3.9 ms -1, sub-cloud layer shear exceeding 7.5 x 10-3 s-1, and a majority of streaks oriented within 20° of the mean sub-cloud layer wind, satisfying many boundary layer roll criteria proposed in past studies. Attempts to reconstruct the 3D cloud liquid water content and 2D column liquid water path across the scanning radar domain using Z (Reflectivity) vs. LWC (Liquid Water Content) regressions trained using the zenith measurements were proved ineffective due to the overall extent of drizzle at Graciosa, and errors associated with sensitivity loss at range. Despite some difficulties, the SWACR satisfied ARM metrics for success by proving effective at detecting weak clouds for extended time periods across a 10 km plane, and drizzle across a 20 km range, at high spatial resolutions. Difficulties in resolving accurate vertical velocity patterns also suggest the need for an adaptive sampling strategy to most effectively remove horizontal wind components.

Bowley, Kevin

385

Multimode Radar Altimeter (MRA).  

National Technical Information Service (NTIS)

Multimode radar altimeter functions in the Comet Nucleus Sample Return mission are described. Range measurement gives distance information for navigation; angle tracking can be performed by optical systems. Velocity (three axes) can be obtained by Doppler...

G. Picardi C. Dai R. Seu A. Coradini

1988-01-01

386

Radar Techniques Program.  

National Technical Information Service (NTIS)

This is the fifth Quarterly Technical Summary covering the development of an airborne Multiple-Antenna Moving-Target Surveillance Radar (MASR) which employs special antenna and signal-processing techniques to provide continuous, wide-area surveillance of ...

C. E. Muehe

1974-01-01

387

Incoherent radar spectra  

Microsoft Academic Search

General expressions for the incoherent scatter spectra are presented. These are relevant for the UHF radar in the monostatic backscatter case (thus excluding only the effect of the magnetic field), based on the Nyquist approach.

Matti K. Vallinkoski

1987-01-01

388

Ultra-wideband radar  

Microsoft Academic Search

Here, we present a description of a block scheme, characteristics, specific features of design and results of testing for a prototype of the ultrawideband (UWB) radar, which has been developed by Russian UWB group researchers at Moscow Aviation Institute at \\

I. Immoreev; E. Ziganshin

2004-01-01

389

Radar investigation of asteroids  

NASA Astrophysics Data System (ADS)

For 80 Sappho, 356 Liguria, 694 Ekard, and 2340 Hathor, data were taken simultaneously in the same sense of circular polarization as transmitted (SC) as well as in the opposite (OC) sense. Graphs show the average OC and SC radar echo power spectra soothed to a resolution of EFB Hz and plotted against Doppler frequency. Radar observations of the peculiar object 2201 Oljato reveal an unusual set of echo power spectra. The albedo and polarization ratio remain fairly constant but the bandwidths range from approximately 0.8 Hz to 1.4 Hz and the spectral shapes vary dramatically. Echo characteristics within any one date's approximately 2.5-hr observation period do not fluctuate very much. Laboratory measurements of the radar frequency electrical properties of particulate metal-plus-silicate mixtures can be combined with radar albedo estimates to constrain the bulk density and metal weight, fraction in a hypothetical asteroid regolith having the same particle size distribution as lab samples.

Ostro, S. J.

390

Seasonal evaluation and spatial variability of suspended particulate matter in the vicinity of a large coal-fired power station in India--a case study.  

PubMed

Coal combustion in the power sector gives rise to the emission of primary and secondary particulate pollutants. Since the emission of pollutants depends on coal quality and combustion technology, and given that transport, transformation and deposition of contaminants depend on regional climatic conditions, specific studies for the power stations is needed to evaluate their environmental impacts. Monitoring of ambient respirable suspended particulate matter (RSPM) and suspended particulate matter (SPM) levels around a large coal-fired power station in India was carried out. The specific objectives were the determination of spatial and seasonal variability in RSPM and SPM levels, and their relationship with meteorological parameters such as wind velocity and relative humidity. The results have shown a marked seasonal trend and spatial variability in RSPM and SPM levels in the study area. Higher concentrations of ambient RSPM and SPM were found in downwind monitoring stations compared to upwind direction. Ratios of RSPM to SPM and correlation coefficient values between RSPM and SPM along with meteorological parameters were also worked out. Relative humidity and wind velocity have shown an inverse relation with particulate deposition pattern. PMID:15869174

Sharma, Rajnikant; Pervez, Yasmeen; Pervez, Shamsh

2005-03-01

391

Theory of Adaptive Radar  

Microsoft Academic Search

This paper reviews the principles of adaptive radar in which both the spatial (antenna pattern) and temporal (Doppler filter) responses of the system are controlled adaptively. An adaptive system senses the angular-Doppler distribution of the external noise field and adjusts a set of radar parameters for maximum signal-to-interference ratio and optimum detection performance. A gradient technique for control of the

L. E. Brennan; L. S. Reed

1973-01-01

392

Radar in transition  

Microsoft Academic Search

It is pointed out that radar engineers, at the end of 1984, find their field in transition between the conventional designs of the post War II era and the digitally controlled, solid-state systems which will be in place for the year 2000. The U.S. Navy has two major phased array radar systems in operation, including the rotating three-dimensional (3D) AN\\/SPS-48,

D. K. Barton

1984-01-01

393

Terminal Doppler weather radar  

Microsoft Academic Search

The terminal Doppler weather radar (TDWR) system, now under development, will provide automatic detection of microbursts and low-level wind shear. This paper discusses the TDWR performance parameters and describes its structural elements, including the antenna subsystem, the transmitter, the receiver\\/exciter, the digital signal processor, and the radar product generator\\/remote monitoring subsystem. Attention is also given to the processes of the

M. Michelson; W. W. Shrader; J. G. Wieler

1990-01-01

394

Evaluation of Two AN/APS-94 Side-Looking Airborne Radar Systems in the Detection of Search and Rescue Targets.  

National Technical Information Service (NTIS)

Since September 1978, side-looking airborne radar (SLAR) detection data have been gathered in conjunction with four visual detection experiments conducted by the U.S.C.G. R&D Center. These are part of a series of experiments designed to improve search pla...

G. L. Hover N. C. Edwards S. R. Osmer T. J. Mazour

1981-01-01

395

Radar Detection of ultra high energy cosmic rays  

NASA Astrophysics Data System (ADS)

We revisit the radar echo technique as an approach to detect ultra high energy cosmic rays (UHECR). The UHECR extensive air showers produce disk-like ionization fronts propagating with a relativistic speed and creating fast decaying plasma. We study the reflection of a radio wave, such as the one from a radar transmitter or commercial radio and TV station, from the ionization front. The reflected wave will be frequency up-shifted due to relativistic Doppler effect. The amplitude of the reflected wave depends strongly on velocity of the front, and density and collision frequency of the plasma behind it. The returned power will be shown for typical extensive air shower parameters. )

Kryemadhi, Abaz; Bakunov, Michael; Maslov, Alex; Novokovskaya, Alina

2010-02-01

396

1. View of three detection radar (DR) antennas. DR 1 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. View of three detection radar (DR) antennas. DR 1 (structure no. 735) on left, DR 2 (structure no. 736) in center, and DR 3 (structure no. 737) looking north 30 degrees west, with tracking radar (large radome) and satcom (satellite communication) system in small radome in view between DR 2 and DR 3 antennae. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

397

Technical evaluation of the noise and isolation testing of the reactor protection system for the Davis Besse Nuclear Power Station, Unit 1  

SciTech Connect

This report documents the technical evaluation of the noise and isolation testing of the reactor protection system (RPS) for the Davis Besse Nuclear Power Station, Unit 1. The testing was performed in accordance to Section 4.6.11, Susceptibility, of MIL-N-19900B, and NRC approved plant test methods. Analysis of the test results shows that the reactor protection system did not degrade below acceptable levels when subjected to electromagnetic, electrostatic, isolation and noise level tests, nor was the system's ability to perform its Class 1E protective functions affected.

Selan, J.C.

1980-01-01

398

Sky Station  

NSDL National Science Digital Library

While satellites are the current backbone of telecommunications and wireless infrastructure, the company that maintains this Web site envisions a completely new technology. The Stratospheric Telecommunications Service (STS) relies on "lighter-than-air platforms which are held in a geo-stationary position in the stratosphere (approximately 21Km) over a major metropolitan area." The Sky Station company documents much of the STS theory online, as well as maintaining news and information articles about the progress of the system's development. US and international organizations have already reserved some of the radio frequency spectrum for stratospheric platforms, and it seems to have considerable support from important agencies.

1997-01-01

399

Simulation of radar rainfall errors and their propagation into rainfall-runoff processes  

NASA Astrophysics Data System (ADS)

Radar rainfall data compared with rain gauge measurements provide higher spatial and temporal resolution. However, radar data obtained form reflectivity patterns are subject to various errors such as errors in Z-R relationship, vertical profile of reflectivity, spatial and temporal sampling, etc. Characterization of such uncertainties in radar data and their effects on hydrologic simulations (e.g., streamflow estimation) is a challenging issue. This study aims to analyze radar rainfall error characteristics empirically to gain information on prosperities of random error representativeness and its temporal and spatial dependency. To empirically analyze error characteristics, high resolution and accurate rain gauge measurements are required. The Goodwin Creek watershed located in the north part of Mississippi is selected for this study due to availability of a dense rain gauge network. A total of 30 rain gauge measurement stations within Goodwin Creak watershed and the NWS Level II radar reflectivity data obtained from the WSR-88dD Memphis radar station with temporal resolution of 5min and spatial resolution of 1 km2 are used in this study. Radar data and rain gauge measurements comparisons are used to estimate overall bias, and statistical characteristics and spatio-temporal dependency of radar rainfall error fields. This information is then used to simulate realizations of radar error patterns with multiple correlated variables using Monte Calro method and the Cholesky decomposition. The generated error fields are then imposed on radar rainfall fields to obtain statistical realizations of input rainfall fields. Each simulated realization is then fed as input to a distributed physically based hydrological model resulting in an ensemble of predicted runoff hydrographs. The study analyzes the propagation of radar errors on the simulation of different rainfall-runoff processes such as streamflow, soil moisture, infiltration, and over-land flooding.

Aghakouchak, A.; Habib, E.

2008-05-01

400

Meteor radar signal processing and error analysis  

NASA Astrophysics Data System (ADS)

Meteor wind radar systems are a powerful tool for study of the horizontal wind field in the mesosphere and lower thermosphere (MLT). While such systems have been operated for many years, virtually no literature has focused on radar system error analysis. The instrumental error may prevent scientists from getting correct conclusions on geophysical variability. The radar system instrumental error comes from different sources, including hardware, software, algorithms and etc. Radar signal processing plays an important role in radar system and advanced signal processing algorithms may dramatically reduce the radar system errors. In this dissertation, radar system error propagation is analyzed and several advanced signal processing algorithms are proposed to optimize the performance of radar system without increasing the instrument costs. The first part of this dissertation is the development of a time-frequency waveform detector, which is invariant to noise level and stable to a wide range of decay rates. This detector is proposed to discriminate the underdense meteor echoes from the background white Gaussian noise. The performance of this detector is examined using Monte Carlo simulations. The resulting probability of detection is shown to outperform the often used power and energy detectors for the same probability of false alarm. Secondly, estimators to determine the Doppler shift, the decay rate and direction of arrival (DOA) of meteors are proposed and evaluated. The performance of these estimators is compared with the analytically derived Cramer-Rao bound (CRB). The results show that the fast maximum likelihood (FML) estimator for determination of the Doppler shift and decay rate and the spatial spectral method for determination of the DOAs perform best among the estimators commonly used on other radar systems. For most cases, the mean square error (MSE) of the estimator meets the CRB above a 10dB SNR. Thus meteor echoes with an estimated SNR below 10dB are discarded due to the potential of producing a biased estimate. The precision of the estimated parameters can then be computed using their CRB values as a proxy for the estimated variance. These errors propagate to form the instrumental errors on the height and horizontal wind measurements. Thirdly, the interferometer configuration of interferometric meteor radar system is studied. The interferometer uses the phase differences measured at different sensor pairs to determine the DOA of the meteor trail. Typically Jones cross is used in most of current meteor radar systems, such as MEDAC and SKYiMet. We have evaluated this configuration with other array geometries,such as 'T', 'L' and circular array to examine their performance on the precision of the DOA estimates. The results show that 'T' array has an overall better CRB than other geometries, while with the yagi antenna pattern as a course determination of the DOA range, the circular array performs the best with the lowest sidelobes on the spatial spectral. A Matlab based planar array design package designed for determination and visualization of the DOA estimation performance for a user designed antenna array was developed. Fourthly, based on the special configuration of the South Pole COBRA system, a low cost computational phase calibration method is proposed. Accurate knowledge of the receiver phase ofsets is another factor that can affect system performance. Lastly, the postprocessing results of the meteor echoes collected during 2005 from the South Pole COBRA system are presented. This radar system is shown to have a precision of 2m/s in the horizontal winds, an azimuth precision of 1o, and an elevation precision of 3o. Preliminary scientific results are presented to verify the effectiveness of our processing scheme, and include the seasonal variation of meteor rates as a function of height, and the vertical structure of large semidiurnal tide observed over the South Pole austral summer. The processing schemes and error analysis methods presented in this dissertation can be easily extended to other meteor radar

Kang, Chunmei

401

Performance of spaceborne bistatic synthetic aperture radar  

Microsoft Academic Search

This paper reports on a model developed for evaluating major system performance of a spaceborne bistatic synthetic aperture radar (SAR) for remote sensing applications. The procedure accounts for formation flying aspects. It is particularly aimed at comparison of monostatic and bistatic cases, and, as a test case, it is applied to study a novel configuration, based on a small satellite

ANTONIO MOCCIA; GIUSEPPE SALZILLO; MARCO D'ERRICO; GIANCARLO RUFINO; GIOVANNI ALBERTI

2005-01-01

402

The Air Traffic Control Radar Beacon System  

Microsoft Academic Search

This paper outlines the major advantages and limitations of the Air Traffic Control Radar Beacon System under evaluation at the Civil Aeronautics Administration Technical Development Center. It discusses the advantages and disadvantages of compatibility, the system traffic capacity problems, and the need for an operational doctrine to restrict the use of interrogators. System coverage, ground antenna, reply-code garbling, and reflection

David S. Crippen

1957-01-01

403

Radar target simulation of space object  

Microsoft Academic Search

This paper describes a target simulation which operates in non real-time to provide full closed-loop operation of the ground based multifunction phased array radar simulation system in support of ballistic missile defence experiments against countermeasure. By simulating the target scattering signature and dynamical signature, this target simulation provide realistic scenario source to evaluate the system performance of multifunction phased array

Zhang Wei; Xie Daihua; Tian Zhong

2008-01-01

404

Radar image processing for the AFIT anechoic chamber  

NASA Astrophysics Data System (ADS)

The purpose of this study was to begin development of an Inverse Synthetic Aperature Radar imaging capability for the AFIT anechoic chamber. This began with an evaluation of the capabilities and limitations of the existing radar system and the chamber itself for this application. Then, after deciding on the image processing approach, software had to be written to collect the data necessary for image processing. This constituted the majority of this study, and resulted in a versatile, user-friendly program that automates the process of collecting data for high-resolution radar images. The program checks that the data to be collected will lead to a valid radar cross-section (RCS) image, but will allow data collection for general radar images. Finally, the image processing software was begun. This made use of commercially available software packages called PC-MATLAB and PRO-MATLAB. Further work is needed on the image processing software to generate calibrated images, and to perform focusing.

Sanders, Brian K.

1990-12-01

405

Water discharge estimates from large radar altimetry datasets in the Amazon basin  

NASA Astrophysics Data System (ADS)

In this study, we evaluate the use of a large radar altimetry dataset as a complementary gauging network capable of providing water discharge in ungauged regions within the Amazon basin. A rating-curve-based methodology is adopted to derive water discharge from altimetric data provided by Envisat at 444 virtual stations (VS). The stage-discharge relations at VS are built based on radar altimetry and outputs from a global flow routing scheme. In order to quantify the impact of modeling uncertainties on rating-curve based discharges, another experiment is performed using simulated discharges derived from a simplified data assimilation procedure. Discharge estimates at 90 VS are evaluated against observations during the curve fitting calibration (2002-2005) and evaluation (2006-2008) periods, resulting in mean relative RMS errors as high as 52% and 12% for experiments without and with assimilation, respectively. Without data assimilation, uncertainty of discharge estimates can be mostly attributed to forcing errors at smaller scales, generating a positive correlation between performance and drainage area. Mean relative errors (RE) of altimetry-based discharges varied from 15% to 92% for large and small drainage areas, respectively. Rating curves produced a mean RE of 54% versus 68% from model outputs. Assimilating discharge data decreases the mean RE from 68% to 12%. These results demonstrate the feasibility of applying the proposed methodology to the regional or global scales. Also, it is shown the potential of satellite altimetry for predicting water discharge in poorly-gauged and ungauged river basins.

Getirana, A. C. V.; Peters-Lidard, C.

2012-06-01

406

Radar-cross-section reduction of wind turbines. part 1.  

SciTech Connect

In recent years, increasing deployment of large wind-turbine farms has become an issue of growing concern for the radar community. The large radar cross section (RCS) presented by wind turbines interferes with radar operation, and the Doppler shift caused by blade rotation causes problems identifying and tracking moving targets. Each new wind-turbine farm installation must be carefully evaluated for potential disruption of radar operation for air defense, air traffic control, weather sensing, and other applications. Several approaches currently exist to minimize conflict between wind-turbine farms and radar installations, including procedural adjustments, radar upgrades, and proper choice of low-impact wind-farm sites, but each has problems with limited effectiveness or prohibitive cost. An alternative approach, heretofore not technically feasible, is to reduce the RCS of wind turbines to the extent that they can be installed near existing radar installations. This report summarizes efforts to reduce wind-turbine RCS, with a particular emphasis on the blades. The report begins with a survey of the wind-turbine RCS-reduction literature to establish a baseline for comparison. The following topics are then addressed: electromagnetic model development and validation, novel material development, integration into wind-turbine fabrication processes, integrated-absorber design, and wind-turbine RCS modeling. Related topics of interest, including alternative mitigation techniques (procedural, at-the-radar, etc.), an introduction to RCS and electromagnetic scattering, and RCS-reduction modeling techniques, can be found in a previous report.

Brock, Billy C.; Loui, Hung; McDonald, Jacob J.; Paquette, Joshua A.; Calkins, David A.; Miller, William K.; Allen, Steven E.; Clem, Paul Gilbert; Patitz, Ward E.

2012-03-05

407

Bistatic Radar In Space A New Dimension In Imaging Radar  

Microsoft Academic Search

Based on a set of examples, this paper shows that bistatic space radar systems can have important capabilities for special imaging radar applications. It explains' the different categories of bistatic space radars as there are single orbit systems, crossing orbit systems, tethered systems and systems with geostationary\\/ge osynchronous transmitters (GEO-BISAR). It discusses the ideas of mixed systems, where aircrafts are

Hans Martin Braun; Philipp Hartl

1989-01-01

408

Studies on Radar and Non-radar Sensor Networks.  

National Technical Information Service (NTIS)

During the period of 12/1/2005--5/30/2006, we expanded our research from generic wireless sensor networks to radar sensor networks. For radar sensor networks, we performed the following preliminary studies: (1) Waveform design and diversity in radar senso...

Q. Liang

2006-01-01

409

33. Perimeter acquisition radar building room #320, perimeter acquisition radar ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

33. Perimeter acquisition radar building room #320, perimeter acquisition radar operations center (PAROC), contains the tactical command and control group equipment required to control the par site. Showing spacetrack monitor console - Stanley R. Mickelsen Safeguard Complex, Perimeter Acquisition Radar Building, Limited Access Area, between Limited Access Patrol Road & Service Road A, Nekoma, Cavalier County, ND

410

Microphysical cross validation of spaceborne radar and ground polarimetric radar  

Microsoft Academic Search

Ground-based polarimetric radar observations along the beam path of the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR), matched in resolution volume and aligned to PR measurements, are used to estimate the parameters of a gamma raindrop size distribution (RSD) model along the radar beam in the presence of rain. The PR operates at 13.8 GHz, and its signal returns

V. Chandrasekar; Steven M. Bolen; Eugenio Gorgucci

2003-01-01

411

Estimating water discharge from large radar altimetry datasets  

NASA Astrophysics Data System (ADS)

The objective of this study is to evaluate the potential of large altimetry datasets as a complementary gauging network capable of providing water discharge in ungauged regions. A rating curve-based methodology is adopted to derive water discharge from altimetric data provided by the Envisat satellite at 475 virtual stations (VS) within the Amazon basin. From a global-scale perspective, the stage-discharge relations at VS are built based on radar altimetry and outputs from a modeling system composed of a land surface model and a global river routing scheme. In order to quantify the impact of model uncertainties on rating-curve based discharges, a second experiment is performed using outputs from a simulation where daily observed discharges at 135 gauging stations are introduced in the modeling system. Discharge estimates at 90 VS are evaluated against observations during the curve fitting calibration (2002-2005) and evaluation (2006-2008) periods, resulting in mean normalized RMS errors as high as 39 and 15% for experiments without and with direct insertion of data, respectively. Without direct insertion, uncertainty of discharge estimates can be mostly attributed to forcing errors at smaller scales, generating a positive correlation between performance and drainage area. Mean relative streamflow volume errors (RE) of altimetry-based discharges varied from 15 to 84% for large and small drainage areas, respectively. Rating curves produced a mean RE of 51% versus 68% from model outputs. Inserting discharge data into the modeling system decreases the mean RE from 51 to 18%, and mean NRMSE from 24 to 9%. These results demonstrate the feasibility of applying the proposed methodology to the continental or global scales.

Getirana, A. C. V.; Peters-Lidard, C.

2013-03-01

412

Mapping Wintering Waterfowl Distributions Using Weather Surveillance Radar  

PubMed Central

The current network of weather surveillance radars within the United States readily detects flying birds and has proven to be a useful remote-sensing tool for ornithological study. Radar reflectivity measures serve as an index to bird density and have been used to quantitatively map landbird distributions during migratory stopover by sampling birds aloft at the onset of nocturnal migratory flights. Our objective was to further develop and validate a similar approach for mapping wintering waterfowl distributions using weather surveillance radar observations at the onset of evening flights. We evaluated data from the Sacramento, CA radar (KDAX) during winters 1998–1999 and 1999–2000. We determined an optimal sampling time by evaluating the accuracy and precision of radar observations at different times during the onset of evening flight relative to observed diurnal distributions of radio-marked birds on the ground. The mean time of evening flight initiation occurred 23 min after sunset with the strongest correlations between reflectivity and waterfowl density on the ground occurring almost immediately after flight initiation. Radar measures became more spatially homogeneous as evening flight progressed because birds dispersed from their departure locations. Radars effectively detected birds to a mean maximum range of 83 km during the first 20 min of evening flight. Using a sun elevation angle of ?5° (28 min after sunset) as our optimal sampling time, we validated our approach using KDAX data and additional data from the Beale Air Force Base, CA (KBBX) radar during winter 1998–1999. Bias-adjusted radar reflectivity of waterfowl aloft was positively related to the observed diurnal density of radio-marked waterfowl locations on the ground. Thus, weather radars provide accurate measures of relative wintering waterfowl density that can be used to comprehensively map their distributions over large spatial extents.

Buler, Jeffrey J.; Randall, Lori A.; Fleskes, Joseph P.; Barrow, Wylie C.; Bogart, Tianna; Kluver, Daria

2012-01-01

413

Passive coherent location radar demonstration  

Microsoft Academic Search

This paper describes a passive coherent location (PCL) radar system developed by Dynetics, Inc. This system uses commercial FM broadcast signals for the radar waveform. This paper presents a technical description of the system and performance data.

C. L. Zoeller; M. J. Moody

2002-01-01

414

Terahertz radar cross section measurements  

Microsoft Academic Search

We present the result of terahertz radar cross section measurements on various objects including models of aircraft fighters. Application of a time domain system provides both values of radar cross section and ranging information.

Krzysztof Iwaszczuk; Henning Heiselberg; Peter Uhd Jepsen

2010-01-01

415

CFAR detection for multistatic radar  

Microsoft Academic Search

A multistatic radar system with n transmitters and one receiver is modelled. Several CFAR algorithms for detection are introduced. The proposed CFAR detectors are simulated and the performances are compared with the performance of a monostatic radar of higher power.

Vahideh Amanipour; Ali Olfat

2008-01-01

416

Interior view to the south of computer work stations in ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior view to the south of computer work stations in front of elevated work area 1570 on left and elevated glassed in work area 1870 on right - Over-the-Horizon Backscatter Radar Network, Mountain Home Air Force Operations Building, On Desert Street at 9th Avenue Mountain Home Air Force Base, Mountain Home, Elmore County, ID

417

Climatology of tropopause folds over a European Arctic station (Esrange)  

Microsoft Academic Search

Eleven years (September 1996 to August 2007) of continuous measurements of three-dimensional wind and backscattered signal strength observed with Esrange Radar (ESRAD) have been utilized to study the annual and interannual variation of tropopause folds over an Arctic station. Two typical tropopause fold events (one is associated with a streamer type of system and the other with a cutoff low)

T. Narayana Rao; J. Arvelius; S. Kirkwood

2008-01-01

418

A simulation study of coherent radar imaging  

NASA Astrophysics Data System (ADS)

Coherent radar imaging (CRI) is used in an attempt to overcome the angular resolution limitation of conventional single-station radars and is used to image the horizontal structure inside the resolution volume. This recently developed technique has been successfully applied to radar observations of the ionosphere as well as the lower atmosphere. However, no statistical analysis of the robustness of the various techniques has been presented to date. In this work, three CRI techniques are reviewed: Fourier-based, Capon's, and maximum entropy (MaxEnt) methods. The Fourier-based method is the simplest of the three algorithms but has inherent resolution limitations. Although quite different in nature and performance, both Capon's and MaxEnt methods can be posed as constrained optimization problems. A statistical comparison of performance of the three CRI techniques, using various receiver configurations and two distinct cases of scattering structure, is made using simulated data. The results show that the MaxEnt method exhibits the best performance in the case of aspect-sensitive scattering with a broad characteristic. In the localized scattering case, however, Capon's method shows superior performance for signals with high signal-to-noise ratio (SNR), but MaxEnt method outperforms all methods for low SNR. In general, both Capon's and MaxEnt methods are able to reproduce the gross characteristics of the scattering media under observation.

Yu, Tian-You; Palmer, Robert D.; Hysell, David L.

2000-09-01

419

Bird migration flight altitudes studied by a network of operational weather radars.  

PubMed

A fully automated method for the detection and quantification of bird migration was developed for operational C-band weather radar, measuring bird density, speed and direction as a function of altitude. These weather radar bird observations have been validated with data from a high-accuracy dedicated bird radar, which was stationed in the measurement volume of weather radar sites in The Netherlands, Belgium and France for a full migration season during autumn 2007 and spring 2008. We show that weather radar can extract near real-time bird density altitude profiles that closely correspond to the density profiles measured by dedicated bird radar. Doppler weather radar can thus be used as a reliable sensor for quantifying bird densities aloft in an operational setting, which--when extended to multiple radars--enables the mapping and continuous monitoring of bird migration flyways. By applying the automated method to a network of weather radars, we observed how mesoscale variability in weather conditions structured the timing and altitude profile of bird migration within single nights. Bird density altitude profiles were observed that consisted of multiple layers, which could be explained from the distinct wind conditions at different take-off sites. Consistently lower bird densities are recorded in The Netherlands compared with sites in France and eastern Belgium, which reveals some of the spatial extent of the dominant Scandinavian flyway over continental Europe. PMID:20519212

Dokter, Adriaan M; Liechti, Felix; Stark, Herbert; Delobbe, Laurent; Tabary, Pierre; Holleman, Iwan

2010-06-02

420

Test and evaluation of load converter topologies used in the Space Station Freedom power management and distribution dc test bed  

NASA Astrophysics Data System (ADS)

Power components hardware in support of the Space Station freedom dc Electric Power System were tested. One type of breadboard hardware tested is the dc Load Converter Unit, which constitutes the power interface between the electric power system and the actual load. These units are dc to dc converters that provide the final system regulation before power is delivered to the load. Three load converters were tested: a series resonant converter, a series inductor switch-mode converter, and a switching full-bridge forward converter. The topology, operation principles, and test results are described, in general. A comparative analysis of the three units is given with respect to efficiency, regulation, short circuit behavior (protection), and transient characteristics.

Lebron, Ramon C.; Oliver, Angela C.; Bodi, Robert F.

421

Evaluation of Manual Ultrasonic Examinations Applied to Detect Flaws in Primary System Dissimilar Metal Welds at North Anna Power Station  

SciTech Connect

During a recent inservice inspection (ISI) of a dissimilar metal weld (DMW) in an inlet (hot leg) steam generator nozzle at North Anna Power Station Unit 1, several axially oriented flaws went undetected by the licensee's manual ultrasonic testing (UT) technique. The flaws were subsequently detected as a result of outside diameter (OD) surface machining in preparation for a full structural weld overlay. The machining operation uncovered the existence of two through-wall flaws, based on the observance of primary water leaking from the DMW. Further ultrasonic tests were then performed, and a total of five axially oriented flaws, classified as primary water stress corrosion cracking (PWSCC), were detected in varied locations around the weld circumference.

Anderson, Michael T.; Diaz, Aaron A.; Doctor, Steven R.

2012-06-01

422

A new Particle Filter for Localization of a Mobile Base Station Based on Microwave Backscatter  

Microsoft Academic Search

This work presents an improved particle filter algorithm for a precise measurement of the local position of a mobile target. The presented measurement system consists of a mobile radar base station to be tracked and several active transponders located at predefined points of the working area. The system measures the range between the transponders and the base station like Frequency

Haytham Qasem; Christoph Ament; Leonhard Reindl

423

The Clementine Bistatic Radar Experiment  

Microsoft Academic Search

During the Clementine 1 mission, a bistatic radar experiment measured the magnitude and polarization of the radar echo versus bistatic angle, beta, for selected lunar areas. Observations of the lunar south pole yield a same-sense polarization enhancement around beta = 0. Analysis shows that the observed enhancement is localized to the permanently shadowed regions of the lunar south pole. Radar

S. Nozette; C. L. Lichtenberg; P. Spudis; R. Bonner; W. Ort; E. Malaret; M. Robinson; E. M. Shoemaker

1996-01-01

424

Scanning ARM Cloud Radar Handbook.  

National Technical Information Service (NTIS)

The scanning ARM cloud radar (SACR) is a polarimetric Doppler radar consisting of three different radar designs based on operating frequency. These are designated as follows: (1) X-band SACR (X-SACR); (2) Ka-band SACR (Ka-SACR); and (3) W-band SACR (W-SAC...

K. Johnson K. Widener N. Bharadwaj

2012-01-01

425

The Venus Radar Mapper mission  

Microsoft Academic Search

The Venus Radar Mapper (VRM) mission is sponsored by NASA to put a single spacecraft in orbit around Venus to map the surface using a synthetic aperture mapping radar. This paper describes the VRM mission at its present state of design. The science objectives and project constraints are described. Key features of the spacecraft system and radar system are discussed.

E. Cutting; J. H. Kwok; S. N. Mohan

1984-01-01

426

A radar tour of Venus  

Microsoft Academic Search

The surface of Venus is briefly characterized in a summary of results obtained by the Soviet Venera 15 and 16 8-cm synthetic-aperture radars, IR radiometers, and radar altimeters. A series of radar images, mainly from Kotelnikov et al. (1984), are presented and discussed, and the descent vehicles to be released by the two Vega spacecraft as they pass Venus in

J. K. Beatty

1985-01-01

427

Radar model with terrain effects  

NASA Astrophysics Data System (ADS)

This thesis presents a novel naval radar model which computes radar detection in the presence of land masses. The model is an interactive computer program which accepts scenarios and radar parameters from the user and displays a map of the area indicating where targets can and cannot be detected. The resulting map can be displayed at the user's computer terminal or printed offline.

Meritt, J. W.

1982-03-01

428

The Shuttle Radar Topography Mission  

Microsoft Academic Search

The Shuttle Radar Topography Mission produced the most complete, highest-resolution digital elevation model of the Earth. The project was a joint endeavor of NASA, the National Geospatial-Intelligence Agency, and the German and Italian Space Agencies and flew in February 2000. It used dual radar antennas to acquire interferometric radar data, processed to digital topographic data at 1 arc sec resolution.

Tom G. Farr; Paul A. Rosen; Edward Caro; Robert Crippen; Riley Duren; Scott Hensley; Michael Kobrick; Mimi Paller; Ernesto Rodriguez; Ladislav Roth; David Seal; Scott Shaffer; Joanne Shimada; Jeffrey Umland; Marian Werner; Michael Oskin; Douglas Burbank; Douglas Alsdorf

2007-01-01

429

Studies on Radar Sensor Networks.  

National Technical Information Service (NTIS)

During the period of 12/8/2006-6/30/2007, we performed the following studies in radar sensor network: (1) Sense-through-foliage target detection using UWB radar sensor network based on real-world data; (2) Foliage clutter modeling using UWB radars; (3) Ou...

Q. Liang

2007-01-01

430

Pulse-Doppler UWB Radar  

Microsoft Academic Search

The paper contains measurement results of moving targets by pulse-Doppler UWB radar. The description of a radar, principle of operation and technical specification are presented. Conditions and results of measurements are described. Feature of the presented measurements: Doppler signals of linear moving targets whose linear sizes exceed resolution of radar

A. Chernenko; E. Ziganshin

2006-01-01

431

Millimeter Radar Sea Return Study.  

National Technical Information Service (NTIS)

A site selection process was performed for a planned field exercise to measure radar sea clutter reflectivity at low grazing angles using several radar frequencies between 9.5 and 95 GHz. A detailed test plan was developed to collect calibrated radar cros...

R. N. Trebits

1979-01-01

432

Polarimetric Monopulse Radar Intelligent Emulator  

Microsoft Academic Search

For debugging polarimetric monopulse radar and testing polarization algorithms, a new polarimetric monopulse radar intelligent emulator is proposed and designed in this paper. The polarization information, as a basic character of the target echo, plays an important role in modern radar detection nowadays. The polarization algorithms are developed with rapid speed. It is not realistic to test all algorithms on

Jin Tao; Qi Xiaohui; Yuan Shuqing; Qiao Xiaolin; Zhang Min; Zhang Qunxing

2007-01-01

433

Development of Hts Microwave Filters for Applications in Mobile Communication, Satellite Receiver and Meteorological Radar  

NASA Astrophysics Data System (ADS)

Recent development in the applications of high temperature superconductor (HTS) filters is introduced. Breakthrough had been made in ultra selective band-pass filter with extremely small fractional bandwidth for 3G mobile base stations. Satisfactory results were achieved in the space qualification mechanical tests of the HTS filters. Field trail of the meteorological radar showed that with HTS subsystem the sensitivity and anti-interference ability of the radar were greatly improved.

Li, Hong; He, Aisheng; Li, Shunzhou; Zhang, Xueqiang; Li, Chunguang; Sun, Liang; Zhang, Qiang; Li, Fei; Luo, Qiang; Gu, Changzhi; He, Yusheng

434

Synthetic Aperture Radar Signals: Formulations and Approaches for Data Analysis.  

National Technical Information Service (NTIS)

This report discusses principles of synthetic aperture radar, properties of radar targets, characteristics of radar imagery, statistical analysis of radar imagery, and the application of modern data analysis.

A. B. Lucero P. Swerling L. Breiman

1975-01-01

435

Evaluating the Potential of Retrieving Vertically-Resolved Cloud Drop Microphysical Properties From APS/RSP Polarization Measurements Combined With Lidar and Radar Using Large-Eddy Simulations  

NASA Astrophysics Data System (ADS)

Multi-spectral, multi-directional polarimetric measurements, such as those made by the Aerosol Polarimetry Sensor (APS) on the forthcoming Glory satellite mission, coupled with co-located CALIPSO/CLOUDSAT lidar and radar measurements have great potential in retrieving accurate information about cloud droplet number concentrations and the vertical distribution of cloud liquid water content, which are crucial quantities for studies on, e.g., indirect aerosol effects. A cloud retrieval algorithm making use of such a combination of measurements has been developed and tested on measurements of an aircraft-mounted version of APS, the Research Scanning Polarimeter (RSP),in combination with aircraft-based lidar and radar measurements. However, validating the retrieval results can be challenging due to lack of validation data or the difficulty of interpreting and comparing retrieval results from different instruments. In this presentation we present an additional validation approach in which APS/RSP, lidar and radar measurements are simulated based on large-eddy simulations of marine stratocumulus fields in various atmospheric conditions. By comparing the quantities retrieved from these simulated measurement with the true values from the large-eddy simulations, we will demonstrate the potential and limitations of this retrieval approach.

Cairns, B.; van Diedenhoven, B.; Ackerman, A. S.

2009-12-01

436

Instrumental Principles of MST Radars and Incoherent Scatter Radars and the Configuration of Radar System Hardware.  

National Technical Information Service (NTIS)

The principle of pulse modulation used in the case of coherent scatter radars (MST radars) is discussed. Coherent detection and the corresponding system configuration is delineated. Antenna requirements and design are outlined and the phase-coherent trans...

J. Roettger

1989-01-01

437

Kiowa Creek Switching Station  

SciTech Connect

The Western Area Power Administration (Western) proposes to construct, operate, and maintain a new Kiowa Creek Switching Station near Orchard in Morgan County, Colorado. Kiowa Creek Switching Station would consist of a fenced area of approximately 300 by 300 feet and contain various electrical equipment typical for a switching station. As part of this new construction, approximately one mile of an existing 115-kilovolt (kV) transmission line will be removed and replaced with a double circuit overhead line. The project will also include a short (one-third mile) realignment of an existing line to permit connection with the new switching station. In accordance with the Council on Environmental Quality (CEQ) regulations for implementing the procedural provisions of the National Environmental Policy Act of 1969 (NEPA), 40 CFR Parts 1500--1508, the Department of Energy (DOE) has determined that an environmental impact statement (EIS) is not required for the proposed project. This determination is based on the information contained in this environmental assessment (EA) prepared by Western. The EA identifies and evaluates the environmental and socioeconomic effects of the proposed action, and concludes that the advance impacts on the human environment resulting from the proposed project would not be significant. 8 refs., 3 figs., 1 tab.

Not Available

1990-03-01

438

Real-time radar rainfall estimation  

NASA Astrophysics Data System (ADS)

This research reports on several aspects of real-time monitoring of the spatial and temporal distribution of rainfall from ground-based weather radar. Optimization of the performance of the National Weather Service's Precipitation Processing Subsystem (PPS) is the first objective. This is achieved by developing a calibration procedure which simultaneously estimates the optimal parameter values by providing a global assessment of the system's performance. Evaluation of the system is based on a data set consisting of two months of radar reflectivity measurements, and hourly raingage rainfall accumulations, from the Melbourne, Florida WSR-88D site. Radar-raingage root mean square (RMS) difference reduction up to 20% with respect to the default system parameter values is demonstrated. Investigation of statistical procedures for real-time adjustment of the mean-field systematic radar rainfall error is the second objective. For this purpose, a data- based Monte Carlo simulation experiment is performed. The study uses an extensive data set of hourly radar rainfall products and raingage accumulations from the Tulsa, Oklahoma WSR-88D site. This intercomparison study concluded to a bias procedure which overall appeared to perform better than the other. The main results from this research are: (1) statistical methods with optimal error model parameters perform significantly better than using only bias observations, and (2) bias adjustment is mostly effective in cold season precipitation measurements. Final objective of this research is development of a new real-time radar rainfall estimation algorithm. The new processing steps introduced in this algorithm are beam- height effect correction, vertical integration, rain classification, and continuous range effect correction. Additionally, the algorithm applies advection correction at the gridded rainfall rates to minimize the temporal sampling effect, and its calibration is cast in a recursive formulation with parameters adjusted in real- time. A new statistical method has been developed for quantification of radar rainfall products uncertainty. Evaluation of the system and the uncertainty quantification method is based on the data set from Melbourne, Florida WSR-88D site. Radar-raingage RMS difference reduction up to 50% with respect to the default PPS is demonstrated for the proposed algorithm.

Anagnostou, Emmanouil Nikolaos

1997-08-01

439

Radar sector blanker  

NASA Astrophysics Data System (ADS)

A radar sector blanker comprises in analog-to-digital converter and a sector controller unit. The analog-to-digital converter receives the analog synchro voltages describing the positioning of a radar antenna and changes these voltages into binary-coded decimal (BCD) information. The sector controller unit comprises a portable housing, a controller system, and a power supply. The controller system includes an OFF comparator circuit, an ON comparator circuit, an S-R latch, and a solid-state switch. Each comparator circuit comprises three cascaded transistor-transistor logic (TTL) integrated chips. The power supply gives a direct-current voltage to the solid-state switch and the TTL chips. The sector blanker blocks transmission for a predetermined rotational region or sector of a radar system.

Hall, Roger B.

1994-03-01

440

Coherent IR radar technology  

NASA Astrophysics Data System (ADS)

Recent progress in the development of coherent IR radar equipment is reviewed, focusing on the Firepond laser radar installation and the more compact systems derived for it. The design and capabilities of Firepond as a long-range satellite-tracking device are outlined. The technological improvements necessary to make laser radar mobile are discussed: a lightweight, stable 5-10-W transmitter laser for both CW and pulsed operation, a 12-element HgCdTe detector array, an eccentric-pupil Ritchey-Chretien telescope, and a combination of near-field phase modification and anamorphic expansion to produce a fan beam of relatively uniform intensity. Sample images obtained with a prototype system are shown, and the applicability of the mobile system to range-resolved coherent DIAL measurement is found to be similar to that of a baseline DIAL system.

Gschwendtner, A. B.; Harney, R. C.; Hull, R. J.

441

Ground based radar  

NASA Astrophysics Data System (ADS)

The current state of turmoil in the world of ballistic missile technology dictates that the U.S. be prepared to deal with a growing ballistic missile threat. To meet this challenge the U.S. Army is developing a new family of ground based radar to support both the Theater Missile Defense and the Strategic Defense Initiatives. This class of radar provides affordable, reliable tracking and discrimination based on mature technology and commonality of design. The commonality of design concept uses technology and components that can be scaled in number, size, and capability. This approach allows ground based radar to support the near term requirements of both tactical and strategic defense and also provide flexibility for more sophisticated future threats.

Ryan, William W.

442

Antarctic meteor observations using the Davis MST and meteor radars  

NASA Astrophysics Data System (ADS)

This paper presents the meteor observations obtained using two radars installed at Davis (68.6°S, 78.0°E), Antarctica. The Davis MST radar was installed primarily for observation of polar mesosphere summer echoes, with additional transmit and receive antennas installed to allow all-sky interferometric meteor radar observations. The Davis meteor radar performs dedicated all-sky interferometric meteor radar observations. The annual count rate variation for both radars peaks in mid-summer and minimizes in early Spring. The height distribution shows significant annual variation, with minimum (maximum) peak heights and maximum (minimum) height widths in early Spring (mid-summer). Although the meteor radar count rate and height distribution variations are consistent with a similar frequency meteor radar operating at Andenes (69.3°N), the peak heights show a much larger variation than at Andenes, while the count rate maximum-to-minimum ratios show a much smaller variation. Investigation of the effects of the temporal sampling parameters suggests that these differences are consistent with the different temporal sampling strategies used by the Davis and Andenes meteor radars. The new radiant mapping procedure of [Jones, J., Jones, W., Meteor radiant activity mapping using single-station radar observations, Mon. Not. R. Astron. Soc., 367(3), 1050-1056, doi: 10.1111/j.1365-2966.2006.10025.x, 2006] is investigated. The technique is used to detect the Southern delta-Aquarid meteor shower, and a previously unknown weak shower. Meteoroid speeds obtained using the Fresnel transform are presented. The diurnal, annual, and height variation of meteoroid speeds are presented, with the results found to be consistent with those obtained using specular meteor radars. Meteoroid speed estimates for echoes identified as Southern delta-Aquarid and Sextantid meteor candidates show good agreement with the theoretical pre-atmospheric speeds of these showers (41 km s -1 and 32 km s -1, respectively). The meteoroid speeds estimated for these showers show decreasing speed with decreasing height, consistent with the effects of meteoroid deceleration. Finally, we illustrate how the new radiant mapping and meteoroid speed techniques can be combined for unambiguous meteor shower detection, and use these techniques to detect a previously unknown weak shower.

Holdsworth, David A.; Murphy, Damian J.; Reid, Iain M.; Morris, Ray J.

2008-07-01

443

Flashlight radar: A three-dimensional imaging radar  

NASA Astrophysics Data System (ADS)

In support of several programs at Lincoln Laboratory, a small focused-beam polarimetric, millimeter-wave radar scatterometer (an instrument for measuring radar cross section) has been developed. An overview of the design of this Flashlight Radar is presented. Theoretical and empirical studies of antenna performance are discussed. The backscatter theory relating to the characteristics of the Flashlight Radar as a scatterometer is presented, and experimental RCS measurements are compared with theoretical predictions. The data processing steps (polarimetric calibration and compensation, signal processing, and image formation) are described. We show the results of two representative experiments using the Flashlight Radar. The first is a measurement of dihedral and trihedral reflectors with and without radar camouflage. The second is a faster scan of a truck tire, highlighting the radar's fine resolution and its ability to collect three-dimensional data.

Blejer, Dennis J.; Ferranti, Richard L.; Barnes, Richard M.; Irving, William W.; Verbout, Shawn M.

1989-08-01

444

Radar detection of phobos.  

PubMed

Radar echoes from the martian satellite Phobos provide information about that object's surface properties at scales near the 3.5-cm observing wavelength. Phobos appears less rough than the moon at centimeter-to-decimeter scales. The uppermost few decimeters of the satellite's regolith have a mean bulk density within 20% of 2.0 g cm(-3). The radar signature of Phobos (albedo, polarization ratio, and echo spectral shape) differs from signatures measured for small, Earth-approaching objects, but resembles those of large (>/=100-km), C-class, mainbelt asteroids. PMID:17847261

Ostro, S J; Jurgens, R F; Yeomans, D K; Standish, E M; Greiner, W

1989-03-24

445

Terminal Doppler weather radar  

NASA Astrophysics Data System (ADS)

The terminal Doppler weather radar (TDWR) system, now under development, will provide automatic detection of microbursts and low-level wind shear. This paper discusses the TDWR performance parameters and describes its structural elements, including the antenna subsystem, the transmitter, the receiver/exciter, the digital signal processor, and the radar product generator/remote monitoring subsystem. Attention is also given to the processes of the base data formation, point target removal, signal-to-noise thresholding, and velocity de-aliasing and to the TDWR algorithms and displays. A schematic diagram of the TDWR system is presented.

Michelson, M.; Shrader, W. W.; Wieler, J. G.

1990-02-01

446

Wavelets and impulse radar  

NASA Astrophysics Data System (ADS)

The signal generated by avalanche discharge circuitry that drives optical flash for cameras is ultra wideband and suitable as the excitation waveform for an Impulse Radar when transmitted through an appropriate antenna. In this paper, we experimentally and theoretically show that the Impulse Radar's radiated transmitted EM waves satisfy the admissibility condition of wavelets, i.e. (i) a finite power spectral density psd=<|S(f)|2>< and (ii) zero total area under the undulated wave amplitudes. If the radiated environment is linear (the natural scene), then the received signal also satisfies the admissibility condition.

Szu, Harold; Hsu, Charles; Scheff, Kim; Hansen, Peter; Willey, Jeff

2009-04-01

447

Lunar topography from earth-based radar interferometric mapping  

NASA Astrophysics Data System (ADS)

An incomplete knowledge of the topography of the Moon has hindered the solution to several problems in lunar science and comparative planetology. The lack of elevation data over the polar regions and the generally sparse coverage in non-equatorial areas have restricted investigations related to the global shape of the Moon, impact cratering processes, and the possible presence of water ice at the lunar poles. Three-dimensional maps of the nearside and polar regions of the Moon can be obtained with an Earth-based radar interferometer. This technique allows surface heights to be accurately measured from the relative phase between radar echoes recorded at two separate receiving stations. The 70 m antenna and several 34 m stations of the Deep Space Network in California were configured as a radar interferometer for a sequence of observations in 1997. This experiment provided the first detailed topographic maps of the lunar polar regions, with a coverage of 300 x 1200 km at each pole. Elevation maps and radar imagery were also obtained for a 200 x 200 km region centered on Tycho Crater, the freshest large crater on the Moon. With a surface resolution of 150 m and a height resolution of 50 m or better, the radar maps represent significant improvements compared to existing lunar topographic data sets. The digital elevation model of Tycho Crater was used to determine the fundamental parameters of the crater's shape. The data revealed an asymmetry in floor elevations, rim heights, and wall slump zones, which may be related to an oblique nature for the impact. The topographic maps of the polar areas were used to verify previous estimates of global shape parameters for the Moon, and to locate regions which are in permanent shadow from solar illumination. The actual locations of the cold traps, potential reservoirs of ice deposits, are delineated on radar images of the lunar polar areas.

Margot, Jean-Luc C.

1999-09-01

448

Comparison and integration of Landsat optical and PALSAR quad polarization radar: a case study in Bangladesh  

NASA Astrophysics Data System (ADS)

With the recent increase in the availability of quad polarization radar data, the need to assess the utility of these datasets for land cover/use classification is important. The relative classification accuracies of four land covers/uses in Bangladesh using spaceborne quad polarization radar from the Japanese ALOS PALSAR system and optical Landsat Thematic Mapper (TM) data were evaluated. In addition, the utility of radar texture and sensor fusion were analyzed. Supervised signature extraction and classification (maximum likelihood) were used to classify different land covers/uses followed by an accuracy assessment. The original four-band radar had an overall accuracy of 91%. Variance texture was the most useful of the four measures examined, but did not improve overall or individual class accuracies over the original radar. Landsat provided a higher overall classification accuracy (94%) as compared to radar. The merger of Landsat with the original radar increased overall accuracy to 99%, which indicates the advantages of sensor integration.

Sheoran, Arjun; Haack, Barry

2013-01-01

449

Community Radio Stations as Community Technology Centers: An Evaluation of the Development Impact of Technological Hybridization on Stakeholder Communities in South Africa  

Microsoft Academic Search

This study investigated the impact of using community radio stations to extend information and communication technology (ICT) benefits to poor communities in South Africa. Six community radio stations in six rural South African communities were studied, using face-to-face interviews, community conversations, and observation method. The study found these radio stations have ICT presence, but because of a lack of resources

Eronini R. Megwa

2007-01-01

450

Multipath track fusion for over-the-horizon radar  

NASA Astrophysics Data System (ADS)

Over-the-horizon skywave radar exploits ionospheric propagation of HF signals to detect targets beyond the line-of-sight horizon. Multiple propagation paths between the radar sites and the target are often encountered, giving multiple resolved detections for a single target. An algorithm for the fusion of multipath tracks is outlined here which accounts for uncertainty in the coordinate registration transformation to ground coordinates. A multihypothesis track association procedure is described which may be appended to existing radar coordinate tracking filters. The probability for each feasible track association hypothesis is computed, and fused estimates for target states in ground coordinates are evaluated for each hypothesis.

Percival, Douglas J.; White, Kruger A.

1997-10-01

451

Radar data processing. Volume 2 - Advanced topics and applications  

NASA Astrophysics Data System (ADS)

The design and implementation of the radar data processing (RDP) theory are discussed. Data processing for netted monostatic and bistatic radar systems and technical problems such as the misalignment between radars and target altitude uncertainty are examined. The organization and display of the data on a computer system are studied. The computer simulation of tracking algorithms for RDP performance evaluation and the application of the simulation technique to monoradar and multiradar tracking algorithms are analyzed. The use of RDP in air-traffic control systems, maritime navigation surveillance, and defense systems is investigated. Computer requirements for the implementation of RDP algorithms are described.

Farina, A.; Studer, F. A.

452

Observation of snowfall with a low-power FM-CW K-band radar (Micro Rain Radar)  

NASA Astrophysics Data System (ADS)

Quantifying snowfall intensity especially under arctic conditions is a challenge because wind and snow drift deteriorate estimates obtained from both ground-based gauges and disdrometers. Ground-based remote sensing with active instruments might be a solution because they can measure well above drifting snow and do not suffer from flow distortions by the instrument. Clear disadvantages are, however, the dependency of e.g. radar returns on snow habit which might lead to similar large uncertainties. Moreover, high sensitivity radars are still far too costly to operate in a network and under harsh conditions. In this paper we compare returns from a low-cost, low-power vertically pointing FM-CW radar (Micro Rain Radar, MRR) operating at 24.1 GHz with returns from a 35.5 GHz cloud radar (MIRA36) for dry snowfall during a 6-month observation period at an Alpine station (Environmental Research Station Schneefernerhaus, UFS) at 2,650 m height above sea level. The goal was to quantify the potential and limitations of the MRR in relation to what is achievable by a cloud radar. The operational MRR procedures to derive standard radar variables like effective reflectivity factor ( Z e) or the mean Doppler velocity ( W) had to be modified for snowfall since the MRR was originally designed for rain observations. Since the radar returns from snowfall are weaker than from comparable rainfall, the behavior of the MRR close to its detection threshold has been analyzed and a method is proposed to quantify the noise level of the MRR based on clear sky observations. By converting the resulting MRR- Z e into 35.5 GHz equivalent Z e values, a remaining difference below 1 dBz with slightly higher values close to the noise threshold could be obtained. Due to the much higher sensitivity of MIRA36, the transition of the MRR from the true signal to noise can be observed, which agrees well with the independent clear sky noise estimate. The mean Doppler velocity differences between both radars are below 0.3 ms-1. The distribution of Z e values from MIRA36 are finally used to estimate the uncertainty of retrieved snowfall and snow accumulation with the MRR. At UFS low snowfall rates missed by the MRR are negligible when comparing snow accumulation, which were mainly caused by intensities between 0.1 and 0.8 mm h-1. The MRR overestimates the total snow accumulation by about 7%. This error is much smaller than the error caused by uncertain Z e-snowfall rate relations, which would affect the MIRA36 estimated to a similar degree.

Kneifel, Stefan; Maahn, Maximilian; Peters, Gerhard; Simmer, Clemens

2011-06-01

453

Radar investigations of surface wave variability in shelf zone  

Microsoft Academic Search

Complex ground-truth experiments were carried out in the north-eastern part of the Black Sea for several years. The main goal of the study was to record possible manifestations of nonuniform flows on the sea surface. In the experiments, we employed shipboard-type radar stations (RS) Icom and Furuno of the X range and HH polarization, radio scatterometers of the X and

Victor Bakhanov; Nikolai Bogatov; Aleksei Ermoshkin; Emma Zuikova; Vasilii Kazakov; Olga Kemarskaya; Irina Repina; Victor Titov

2010-01-01

454

Continuous Forecasting and Evaluation of Derived Z-R Relationships in a Sparse Rain Gauge Network Using NEXRAD  

NASA Astrophysics Data System (ADS)

Accurate gauge corrected radar rainfall predictions are necessary for making operational hydrologic predictions. Radar rainfall estimates derived from conversion of reflectivity are known to contain systematic errors, or bias, and other random errors or artifacts that can limit the utility of radar rainfall. Quality control and enhancement of radar rainfall estimates may be accomplished through gauge-adjustment procedures and the development of seasonally, spatially and temporal specific Z-R relationships. Default Z-R relationships have been developed to predict rainfall rates from radar reflectivity. These default Z-R relationships can be used to get rainfall predictions before the perspective storms cross over gauge networks, before near real time calibration and bias corrections can be completed. The purpose of this project is to derive and evaluate the uncertainty in Z-R relationships for the Miami, and two other NEXRAD stations covering the South Florida Water Management District, and then develop an implementation scheme for derived Z-R relationships used to improve the NEXRAD rainfall data. To assess improvements in radar rainfall estimation, Z-R relationships are derived that are specific to each radar. These relationships are derived through seasonal characterization of gauge and radar observations for each radar covering coastal and inland regions. The derived Z-R relationships are evaluated using rain gauges withheld for cross validation. Methods used in forecasting include persistence, seasonal trends, autoregressive, and Kalman Filter methods. Results will be presented that demonstrate the efficiency of the methods for forecasting of Z-R coefficients used in rainfall estimation.

Rendon, S.; Vieux, B. E.; Pathak, C. S.

2010-12-01

455

Technical-Evaluation Report on the Adequacy of Station Electric-Distribution-System Voltages for the H.B. Robinson Steam Electric Plant, Unit 2 (Docket No. 50-261).  

National Technical Information Service (NTIS)

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the H.B. Robinson Steam Electric Plant, Unit 2. The evaluation is to determine if the onsite distribution system in conjunction with th...

J. C. Selan

1983-01-01

456

Technical-Evaluation Report on the Monitoring of Electric Power to the Reactor-Protection System for the Peach Bottom Atomic Power Station Units 2 and 3 (Docket Nos. 50-277, 50-278.  

National Technical Information Service (NTIS)

This report documents the technical evaluation of the monitoring of electric power to the reactor protection system (RPS) at the Peach Bottom Atomic Power Station, Units 2 and 3. The evaluation is to determine if the proposed design modification will prot...

J. C. Selan

1983-01-01

457

Bistatic synthetic aperture radar  

Microsoft Academic Search

Synthetic aperture radar (SAR) is becoming increasingly important in many military ground surveillance and targeting roles because of its ability to operate in all weather, day and night, and to detect, classify and geolocate objects at long stand-off ranges. Bistatic SAR, where the transmitter and receiver are on separate platforms, is seen as a potential means of countering vulnerability. This

A. M. Horne; G. Yates

2002-01-01

458

Heat Resistant Radar Absorber.  

National Technical Information Service (NTIS)

A foamed ceramic slab is bonded to the three-layer polyimide RAM substrate to produce a radar absorbed capable of at least 10db absorptivity of the range 3 to at least 10 GHZ and of withstanding very high temperatures, for example, 3000 F for 80 seconds o...

W. P. Manning W. T. Passiuk

1978-01-01

459

Goldstone solar system radar  

Microsoft Academic Search

Information is provided about physical nature planetary surfaces and their topography as well as dynamical properties such as orbits and spin states using ground based radar as a remote sensing tool. Accessible targets are the terrestrial planets: the Earth's Moon, Mercury, Venus and Mars, the outer planets rings and major moons, and many transient objects such as asteroids and comets.

R. F. Jurgens; P. E. Clark; R. M. Goldstein; S. J. Ostro; M. A. Slade; T. W. Thompson; R. S. Saunders

1986-01-01

460

Airborne firefinder radar concept  

Microsoft Academic Search

An airborne firefinder radar (AFFR) is suggested for an upgraded version of the forthcoming Global Hawk Unmanned Aerial Vehicle (UAV). The AFFR could detect an artillery shell within 1 second of firing and, within a few seconds, determine its trajectory origin location (position of the gun) to a circular error probable (CEP) of less than 50 meters. The AFFR could

R. J. Sullivan; J. F. Nicoll; J. M. Ralston

1998-01-01

461

Doppler Radar System.  

National Technical Information Service (NTIS)

The radar system is utilized to guide a fused guided missile to an aircraft target. The secondary doppler effects are utilized between a moving object and a secondary reflecting surface to detect the presence of the object and indicate its point of closes...

A. E. Resnik

1964-01-01

462

Mars 96 subsurface radar  

Microsoft Academic Search

The Mars 96 International Scientific Mission to launch an aerostat that will drift in the Martian atmosphere for ten days is described. The stabilizing element of the aerostat (guiderope) will be dragged on the Martian surface every night. A ground penetrating radar will be installed within the guiderope. Its external surface will act as a transmit and receive antenna. A

Y. Barbin; W. Kofman; M. Elkine; M. Finkelstein; V. Glotov; V. Zolotarev

1991-01-01

463

Passive Radar Tracking Apparatus.  

National Technical Information Service (NTIS)

The radar system tracks a target whether it generates a signal of its own or not and may be used to sense noise energy radiated by the sun, other objects, or other celestial bodies. The system includes an antenna assembly of four horns arranged in a recta...

D. K. Barton W. J. Rose

1965-01-01

464

Comet radar explorer  

Microsoft Academic Search

The Comet Radar Explorer (CORE) is designed to perform a comprehensive and detailed exploration of the interior, surface, and inner coma structures of a scientifically impor-tant Jupiter family comet. These structures will be used to investigate the origins of cometary nuclei, their physical and geological evolution, and the mechanisms driving their spectacular activity. CORE is a high heritage spacecraft, injected

Tony Farnham; Erik Asphaug; Antonella Barucci; Mike Belton; Dominique Bockelee-Morvan; Donald Brownlee; Maria Teresa Capria; Lynn Carter; Steve Chesley; Robert Gaskell; Young Gim; Essam Heggy; Alain Herique; Ken Klaasen; Wlodek Kofman; Misha Kreslavsky; Casey Lisse; Roberto Orosei; Jeff Plaut; Dan Scheeres

2010-01-01

465

Pulse Doppler radar waveforms  

Microsoft Academic Search

Modern military airborne radars are highly sophisticated, multi-mode systems which are required to detect difficult targets in all aspects and over a large range\\/velocity detection space. There are particular difficulties associated with the airborne case such as the limited antenna aperture, high platform velocity and severe clutter levels which present difficult waveform design challenges. This tutorial will consider the design

C. M. Alabaster

2010-01-01

466

Laser Imaging Radar System.  

National Technical Information Service (NTIS)

The simplicity, compactness, and reasonable cost of direct detection diode-laser range finders provide incentive for their use in laser imaging radar systems (LIRS). Efforts have been made to increase range performance of a diode-laser range finder by mea...

S. P. Yun R. A. Olson

1993-01-01

467

Evaluation of geophysical logs, Phase II, at Willow Grove Naval Air Station Joint Reserve Base, Montgomery County, Pennsylvania  

USGS Publications Warehouse

Between March and April 1998, the U.S. Navy contracted Tetra Tech NUS Inc., to drill two monitor wells in the Stockton Formation at the Willow Grove Naval Air Station Joint Reserve Base, Horsham Township, Montgomery County, Pa. The wells MG-1634 and MG-1635 were installed to monitor water levels and sample contaminants in the shallow, intermediate, and deep water-producing zones of the fractured bedrock. Chemical analyses of the samples will help determine the horizontal and vertical distribution of any contaminated ground water migrating from known contaminant sources. Wells were drilled near the Fire Training Area (Site 5). Depths of all boreholes range from 69 to 149 feet below land surface. The U.S. Geological Survey conducted borehole geophysical logging and video surveys to identify water-producing zones in newly drilled monitor wells MG-1634 and MG-1635 and in wells MG-1675 and MG-1676. The logging was conducted from March 5, 1998, to April 16, 1998. This work is a continuation of the Phase I work. Caliper logs and video surveys were used to locate fractures; inflections on fluid-temperature and fluid-resistivity logs were used to locate possible water-producing fractures. Heatpulse-flowmeter measurements were used to verify the locations of water-producing or water-receiving zones and to measure rates of flow between water-bearing fractures. Single-point-resistance and natural-gamma logs provided information on stratigraphy. After interpretation of geophysical logs, video surveys, and driller's notes, wells MG-1634 and MG-1635 were screened such that water-levels fluctuations could be monitored and discrete water samples collected from one or more water-producing zones in each borehole.

Conger, Randall W.

1999-01-01

468

Space Station Live: Station Communications Upgrade  

NASA Video Gallery

NASA Public Affairs Officer Nicole Cloutier-Lemasters recently spoke with Penny Roberts, one of the leads for the International Space Station Avionics and Software group, about the upgrade of the Ku-band communications gear aboard the station.

Gerald T Wright

2013-04-12

469

Mapping bathymetry using X-band marine radar data recorded from a moving vessel  

NASA Astrophysics Data System (ADS)

Marine radars mounted on ships can provide remarkable insights into ocean behaviour from distances of several kilometres, placing other in situ observations and the environment around a ship into a wider oceanographic context. It has been known for some time that it is possible to map shallow water bathymetry and currents using radar image sequences recorded from shore based stations. However, a long standing question from military and hydrographic communities has been whether such techniques can be applied to radar data collected by moving vessels. If so, this presents the possibility of mapping large areas of shallow or coastal seas (albeit with a somewhat coarse horizontal resolution of 50-100 m) prior to the surveying vessel actually having to travel into potentially uncharted or dangerous shallow water areas. Trial sets of radar data were recorded by the Canadian Forces Auxiliary Vessel Quest using a Wamos radar digitiser connected to a Decca navigation radar during a number of deployments around Nova Scotia in 2008 and 2009. Georeferencing corrections derived from the existing ship navigation systems were sufficient to al