scholarly journals The STARE/SABRE story

2014 ◽  
Vol 5 (1) ◽  
pp. 63-72 ◽  
Author(s):  
E. Nielsen ◽  
W. Schmidt
Keyword(s):  
Radar System ◽  
Continuous Operation ◽  
Field Of View ◽  
Good Time ◽  
Similar System ◽  
Successful Experiment ◽  
Spatial Coverage ◽  
New Type ◽  
Time Variations ◽  
Good Time Resolution

Abstract. In January 1977 a new type of radar aurora experiment named STARE (Scandinavian Twin Aurora Radar Experiment) commenced operation in northern Scandinavia. The purpose of the experiment was two-fold: to make observations of the nature of radar auroras, and to contribute to the study of solar–terrestrial relationships (or space weather). The experiment was designed for automatic continuous operation, and for nearly two and a half decades it provided estimates of electron flows with good spatial coverage and resolution and good time resolution. It was a successful experiment that yielded a wealth of observations and results, pertaining to, and based on, the observed time variations of the electron flows and to the spatial flow pattern observed at any given time. This radar system inspired the creation of a similar system, SABRE (Sweden And Britain Radar Experiment), which increased the field of view towards the southwest of STARE. This system commenced operation in 1982.

scholarly journals Improving the Photometry of the Pi of the Sky System

10.14311/1342 ◽  
2011 ◽  
Vol 51 (1) ◽  
Author(s):  
A. F. Żarnecki ◽  
K. Małek ◽  
M. Sokołowski
Keyword(s):  
Gamma Ray ◽  
Field Of View ◽  
Good Time ◽  
Calibration Algorithm ◽  
Sophisticated Instrument ◽  
The Stability ◽  
Robotic Telescope ◽  
Prototype Detector ◽  
Good Time Resolution ◽  
Supernovae Stars

The “Pi of the Sky” robotic telescope was designed to monitor a significant fraction of the sky with good time resolution and range. The main goal of the “Pi of the Sky” detector is to look for short timescale optical transients arising from various astrophysical phenomena, mainly for the optical counterparts of Gamma Ray Bursts (GRB). The system design, the observation methodology and the algorithms that have been developed make this detector a sophisticated instrument for looking for novae and supernovae stars and for monitoring blasars and AGNs activity. The final detector will consist of two sets of 12 cameras, one camera covering a field of view of 20◦ ×20◦. For data taken with the prototype detector at the Las Campanas Observatory, Chile, photometry uncertainty of 0.018–0.024 magnitudo for stars 7–10m was obtained. With a new calibration algorithm taking into account the spectral type of reference stars, the stability of the photometry algorithm can be significantly improved. Preliminary results from the BGInd variable are presented, showing that uncertainty of the order of 0.013 can be obtained.

scholarly journals WAPP — Wideband Arecibo Pulsar Processor

2000 ◽  
Vol 177 ◽  
pp. 275-276 ◽  
Author(s):  
A. Dowd ◽  
W. Sisk ◽  
J. Hagen
Keyword(s):  
Time Resolution ◽  
Good Time ◽  
Key Features ◽  
Arecibo Observatory ◽  
Good Time Resolution

AbstractThe WAPP is a new Pulsar Processor for Arecibo Observatory. Key features are wideband operation (100 MHz) and good time resolution (16 microseconds).

A New Airborne Doppler Radar

1962 ◽  
Vol 15 (4) ◽  
pp. 439-442
Author(s):  
Minoru Okada ◽  
Jun Tamiya
Keyword(s):  
Angular Velocity ◽  
Doppler Radar ◽  
Vertical Axis ◽  
Radar System ◽  
Low Speed ◽  
Single Beam ◽  
Depression Angle ◽  
New Type ◽  
Airborne Doppler Radar

Many airborne doppler radars in use at present work with several beams in fixed directions and a pair of beams switched in sequence. In this paper, which was presented at the convention held in Dusseldorf in May 1961 (Journal, 14, 480), a new type of doppler radar is described in which a single beam is rotated around the vertical axis with a uniform angular velocity, keeping the depression angle constant. With this type of radar, combined with certain circuits in the transmitter-receiver, the frequency tracker and the data stabilizer, it is possible to measure the velocity of positive as well as negative values (including zero); it also allows easier functioning of data-stabilization. Further, a small and lightweight radar system may be constructed in this manner. This type of doppler radar is considered to be of particular use for small, low-speed aircraft.

The Time-Frequency Resolution of Short Time Fourier Transform Based on Multi-Window Functions

2011 ◽  
Vol 214 ◽  
pp. 122-127 ◽  
Author(s):  
Li Hua Wang ◽  
Qi Dong Zhang ◽  
Yong Hong Zhang ◽  
Kai Zhang
Keyword(s):  
Fourier Transform ◽  
Time Resolution ◽  
High Performance ◽  
Frequency Resolution ◽  
Good Time ◽  
Short Time Fourier Transform ◽  
Time Frequency ◽  
Window Functions ◽  
Short Time ◽  
Good Time Resolution

The short-time Fourier transform has the disadvantage that is does not localize time and frequency phenomena very well. Instead the time-frequency information is scattered which depends on the length of the window. It is not possible to have arbitrarily good time resolution simultaneously with good frequency resolution. In this paper, a new method that uses the short-time Fourier transform based on multi-window functions to enhance time-frequency resolution of signals has been proposed. Simulation and experimental results present the high performance of the proposed method.

scholarly journals THE USE OF CCTV IN THE EMERGENCY RESPONSE: A 3D GIS PERSPECTIVE

2019 ◽  
Vol XLII-4/W15 ◽  
pp. 19-25
Author(s):  
J.-H. Hong ◽  
Y.-H. Lu ◽  
C.-H. Chen
Keyword(s):  
Emergency Response ◽  
Field Of View ◽  
Disaster Relief Operations ◽  
Modern Cities ◽  
Spatial Coverage ◽  
The Status ◽  
Response Team ◽  
Disaster Situation ◽  
Historical Database ◽  
Relief Operations

<p><strong>Abstract.</strong> With the increasing threats and damages from the natural and man-made hazards, emergency response has become a critical challenge to the smart management of modern cities. Due to limited human resources, how to correctly and quickly assess the priority of disaster relief operations remains a major issue to the disaster management. While the emergency response team may continuously receive lots of disaster information from various sources, they are required to validate whether the reported situations is real or not. CCTV systems are one of the primary references for visually presenting the status in reality. However, current maps of CCTV are usually presented in 2D, such that the monitored spatial coverage is also restricted to 2D. From a 3D perspective, this paper proposes to integrate the GIS-based urban data and the field of view (FOV) of CCTV for improving the collection, management and decision making during emergency response. As the pressure for making prompt and correct decision is often overwhelming, the key issue is to find the best CCTV as soon as possible. Although the current result is only preliminary, the proposed approach demonstrates the advantages of enabling a “real” 3D spatial illustration about the spatial coverage information of CCTV systems by linking it to the features in the real world. With such standardized metadata for FOV available, further analysis can be readily developed, such as quickly determine if a feature is visible, if a reported disaster situation can be validated, and assess the area not covered by the current CCTV systems. By including the disaster events from the historical database, the proposed approach allows the responsible agencies to assess if the deployment and management of current CCTV systems can provide a satisfactory spatial coverage for the cities in the mitigation phase.</p>

scholarly journals Error Optimization in Electrical Power Quality Monitoring Data

2019 ◽  
Vol 19 (1) ◽  
pp. 1
Author(s):  
Isdawimah Isdawimah
Keyword(s):  
Electric Power ◽  
Power Quality ◽  
Electrical Power ◽  
Measurement Data ◽  
Good Time ◽  
Power Quality Monitoring ◽  
Quality Of Electric Power ◽  
Error Optimization ◽  
Good Time Resolution

In the application of electrical power quality control, the necessity for data processing becomes very important. The measurement data obtained is the latest data and measured in real time with good time resolution and with low error. The object of research is the quality of electric power, the research is about ways of measuring quality of electrical power to obtain accurate data in accordance with actual conditions. This method is capable of measuring data of electrical power quality that changes very quickly with a low error. This data is used as a basis for improving the quality of electric power accurately and accurately.

scholarly journals Photoelectric Polarimetry of the Tail of Comet Ikey-Seki (1965 VIII)

1976 ◽  
Vol 25 (Part1) ◽  
pp. 92-120 ◽  
Author(s):  
J. L. Weinberg ◽  
D. E. Beeson
Keyword(s):  
High Spatial Resolution ◽  
Small Region ◽  
Field Of View ◽  
Large Field ◽  
Small Range ◽  
Comet Tail ◽  
Small Aperture ◽  
Spatial Coverage ◽  
Phase Angles ◽  
Small Field Of View

With few exceptions, measurements of cometary brightness and polarization have been restricted to regions in or near the coma and therefore to a relatively small range of phase angles. Photoelectric techniques are required for detailed wavelength coverage, whereas large-field photographic techniques are better suited for mapping the large regions of sky spanned by a comet tail. Observations with a small field of view provide high spatial resolution but generally restrict multicolor measurements of brightness and polarization to a small region of the comet. Observations with a large field of view (diameter larger than 1 or 2 deg) provide adequate color and spatial coverage but can result in the loss of detail. A compromise is afforded by Fabry photometry, using a modest telescope of small aperture and relatively large field of view.

scholarly journals 3-D Spectroscopy with a Fourier Transform Spectrometer

1995 ◽  
Vol 149 ◽  
pp. 316-327 ◽  
Author(s):  
J.P. Maillard
Keyword(s):  
Fourier Transform ◽  
Spectral Resolution ◽  
Near Infrared ◽  
Field Of View ◽  
Dark Side ◽  
Fourier Transform Spectrometer ◽  
Array Detectors ◽  
New Type ◽  
Nicmos 3 ◽  
Spectro Imaging

AbstractWith the advent of bidimensional array detectors the throughput advantage of a Fourier Transform Spectrometer (FTS) can be used to create a new type of 3-D spectrometer. The classical multiplex property in the spectral domain of a FTS is multiplied by the number of pixel of the array. The points of the entrance field are all observed in parallel. After discussing the properties of this instrument, the coupling of the FTS of the CFH Telescope to a camera equipped with a NICMOS 3 array is described. With this combination, spectro-imaging in any bandpass between 1 and 2.5 µm is possible within a circular 24” field of view, with a scale of 0.33”/pixel, at seeing-limited spatial resolution. Any spectral resolution is choosable up to 30,000. Illustrations are given by a study of the dark side of Venus at 1.27 µm and of planetary nebulae at 2 µm. Many other objects can benefit from this observing mode in the near infrared. Further developments of this 3-D technique are discussed.

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