TOPOGRAHIC CORRECTIONS FOR GRADIENTS IN AIRBORNE GRAVIMETRY

Geophysics ◽  
1976 ◽  
Vol 41 (6) ◽  
pp. 1346-1352 ◽  
Author(s):  
Sigmund Hammer
Keyword(s):  
Real Time ◽  
Practical Method ◽  
Airborne Gravity ◽  
Airborne Gravimetry

Progress in airborne gradiometer instrumentation has advanced to the point that procedures for determining corrections for the variable effects of topography merit consideration. An approximate practical method, based on real‐time recording of flight elevation and variable terrain clearance as a function of position along the flight line, appears to be appropriate for the purpose. The procedure is similar to that for determing topographic corrections for airborne gravity published previously by the author in Geophysics (Hammer, 1974a).

TOPOGRAPHIC AND TERRAIN CORRECTION FOR AIRBORNE GRAVITY

Geophysics ◽  
1974 ◽  
Vol 39 (4) ◽  
pp. 537-542 ◽  
Author(s):  
Sigmund Hammer
Keyword(s):  
Real Time ◽  
Simple Procedure ◽  
Airborne Gravity ◽  
Airborne Gravimetry ◽  
Terrain Effects ◽  
Order Of Magnitude ◽  
Time Correction ◽  
Simple Product ◽  
Irregular Topography ◽  
Product Series

A simple, convenient procedure is outlined for evaluating topographic and terrain effects in airborne gravimetry. The method assumes that continuous terrain data (flight elevation and terrain clearance) are available along a traverse. The terrain is taken to be uniform to infinity in both directions perpendicular to the flight line. The correction is easily calculated from a simple product series. The error tolerances are not serious. Nonperpendicular, irregular topography cannot be evaluated by this simple procedure, but order of magnitude considerations demonstrate that this problem ordinarily is not prohibitively important. In flight, real‐time correction for topographic and terrain effects is not a major obstacle in the development of airborne gravity exploration.

A Simple and Practical Method for Incorporating Augmented Reality into the Classroom and Laboratory

2018 ◽  
Author(s):  
Kyle Plunkett
Keyword(s):  
Organic Chemistry ◽  
Augmented Reality ◽  
Real Time ◽  
Real World ◽  
Smart Phone ◽  
Practical Method ◽  
Virtual Expert ◽  
Video Projection

This manuscript provides two demonstrations of how Augmented Reality (AR), which is the projection of virtual information onto a real-world object, can be applied in the classroom and in the laboratory. Using only a smart phone and the free HP Reveal app, content rich AR notecards were prepared. The physical notecards are based on Organic Chemistry I reactions and show only a reagent and substrate. Upon interacting with the HP Reveal app, an AR video projection shows the product of the reaction as well as a real-time, hand-drawn curved-arrow mechanism of how the product is formed. Thirty AR notecards based on common Organic Chemistry I reactions and mechanisms are provided in the Supporting Information and are available for widespread use. In addition, the HP Reveal app was used to create AR video projections onto laboratory instrumentation so that a virtual expert can guide the user during the equipment setup and operation.

scholarly journals Real-time analysis and feedback of performance indicators in elite diving

2019 ◽  
Author(s):  
◽  
Adam William Sotheran
Keyword(s):  
Real Time ◽  
Practical Method ◽  
Performance Outcomes ◽  
Training Data ◽  
Strength And Conditioning ◽  
Quality Performance ◽  
Training Interventions ◽  
Sports Science ◽  
Real Time Analysis ◽  
World Class

The difficulty and quality of dives required to win medals in Olympic springboard diving has increased throughout the modern era. A greater understanding of optimal diving technique, increased training opportunity and support from disciplines of sports science and medicine have influenced this trend. Progress towards world class standards is enhanced by objective measurement of performance in a training and competition context from which an assessment of the effect of training interventions can be made, leading to a programme individualised for each diver. A description of kinematic parameters representing high quality performance of the world’s hardest dives did not exist. Standards were therefore defined following analysis of dives performed over five years of springboard competition. This new knowledge contributes to a model called ‘What It Takes To Win’ (WITTW). A practical method to calculate kinematic metrics from dives in training also did not exist, limiting comparison between training and WITTW standards. To bridge this gap, a flexible method for analysing dives in training and competition was developed and a bespoke tool created to calculate and feedback performance data with a greater level of sensitivity than in related studies in the sport. Automatic tracking was designed and implemented to facilitate ‘real-time’ measurement of kinematic data, providing a new training process where objective data added to subjective interpretation of quality throughout training. Four World Class Programme divers were tracked through a season’s preparatory phase. Change in performance was measured and an analysis conducted to compare progress towards WITTW standards and assess the influence of strength and conditioning training in performance outcomes. Statistical analysis of longitudinal training data showed that independent variables relating to ‘best’ performances were not common to all divers and that an individualised set of critical variables could be identified for each diver as strengths around which to focus training.

A Simple and Practical Method for Incorporating Augmented Reality into the Classroom and Laboratory

2018 ◽  
Author(s):  
Kyle Plunkett
Keyword(s):  
Organic Chemistry ◽  
Augmented Reality ◽  
Real Time ◽  
Real World ◽  
Smart Phone ◽  
Practical Method ◽  
Virtual Expert ◽  
Video Projection

This manuscript provides two demonstrations of how Augmented Reality (AR), which is the projection of virtual information onto a real-world object, can be applied in the classroom and in the laboratory. Using only a smart phone and the free HP Reveal app, content rich AR notecards were prepared. The physical notecards are based on Organic Chemistry I reactions and show only a reagent and substrate. Upon interacting with the HP Reveal app, an AR video projection shows the product of the reaction as well as a real-time, hand-drawn curved-arrow mechanism of how the product is formed. Thirty AR notecards based on common Organic Chemistry I reactions and mechanisms are provided in the Supporting Information and are available for widespread use. In addition, the HP Reveal app was used to create AR video projections onto laboratory instrumentation so that a virtual expert can guide the user during the equipment setup and operation.

scholarly journals Practical Method of Adaptive Radiotherapy for Prostate Cancer Using Real-Time Electromagnetic Tracking

2012 ◽  
Vol 82 (5) ◽  
pp. 1903-1911 ◽  
Author(s):  
Jeffrey R. Olsen ◽  
Camille E. Noel ◽  
Kenneth Baker ◽  
Lakshmi Santanam ◽  
Jeff M. Michalski ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Real Time ◽  
Practical Method ◽  
Adaptive Radiotherapy ◽  
Electromagnetic Tracking

scholarly journals Airborne gravimetry: An investigation of filtering

Geophysics ◽  
1999 ◽  
Vol 64 (1) ◽  
pp. 61-69 ◽  
Author(s):  
Vicki A. Childers ◽  
Robin E. Bell ◽  
John M. Brozena
Keyword(s):  
Gravity Data ◽  
Substantial Improvement ◽  
Airborne Gravity ◽  
Airborne Gravimetry ◽  
Pass Filter ◽  
Low Pass Filter ◽  
West Antarctic ◽  
Low Pass ◽  
Filter Approach ◽  
Gravity Signal

Low‐pass filtering in airborne gravimetry data processing plays a fundamental role in determining the spectral content and amplitude of the free‐air anomaly. Traditional filters used in airborne gravimetry, the 6 × 20-s resistor‐capacitor (RC) filter and the 300-s Gaussian filter, heavily attenuate the waveband of the gravity signal. As we strive to reduce the overall error budget to the sub-mGal level, an important step is to evaluate the choice and design of the low‐pass filter employed in airborne gravimetry to optimize gravity anomaly recovery and noise attenuation. This study evaluates low‐pass filtering options and presents a survey‐specific frequency domain filter that employs the fast Fourier transform (FFT) for airborne gravity data. This study recommends a new approach to low‐pass filtering airborne data. For a given survey, the filter is designed to maximize the target gravity signal based upon survey parameters and the character of measurement noise. This survey‐specific low‐pass filter approach is applied to two aerogravimetry surveys: one conducted in West Antarctica and the other in the eastern Pacific off the California coast. A reflight comparison with the West Antarctic survey shows that anomaly amplitudes are increased while slightly improving the rms fit between the reflown survey lines when an appropriately designed FFT filter is employed instead of the traditionally used filters. A comparison of the East Pacific survey with high‐resolution shipboard gravity data indicates anomaly amplitude improvements of up to 20 mGal and a 49% improvement of the rms fit from 3.99 mGal to 2.04 mGal with the appropriately designed FFT filter. These results demonstrate that substantial improvement in anomaly amplitude and wavelength can be attained by tailoring the filter to the survey.

scholarly journals Airborne gravimetry from a small twin engine aircraft over the Long Island Sound

Geophysics ◽  
1991 ◽  
Vol 56 (9) ◽  
pp. 1486-1493 ◽  
Author(s):  
Robin E. Bell ◽  
Bernard J. Coakley ◽  
Robert W. Stemp
Keyword(s):  
Gravity Field ◽  
Long Island ◽  
Gravity Anomalies ◽  
Long Island Sound ◽  
Airborne Gravity ◽  
Airborne Gravimetry ◽  
Radar Altimeter ◽  
Gravity Measurements ◽  
Stabilized Platform ◽  
Island Sound

In January 1990, a test of the feasibility of airborne gravimetry from a small geophysical survey aircraft, a Cessna 404, was conducted over the Long Island Sound using a Bell Aerospace BGM-3 sea gravity meter. Gravity has been measured from large aircraft and specially modified de Havilland Twin Otters but never from small, standard survey aircraft. The gravity field of the Long Island Sound is dominated by an asymmetric positive 30 mGal anomaly which is well constrained by both marine and land gravity measurements. Using a Trimble 4000 GPS receiver to record the aircraft’s horizontal position and radar altimeter elevations to recover the vertical accelerations, gravity anomalies along a total of 65 km were successfully measured. The root mean square (rms) difference between the airborne results and marine measurements within 2 km of the flight path was 2.6 mGal for 15 measured values. The anomalies recovered from airborne gravimetry can also be compared with the gridded regional free air gravity field calculated using all available marine and land gravity measurements. The rms difference between 458 airborne gravity measurements and the regional gravity field is 2.7 mGal. This preliminary experiment demonstrates that gravity anomalies, with wavelengths as short as 5 km, can be measured from small aircraft with accuracies of 2.7 mGal or better. The gravity measurements could be improved by higher quality vertical and horizontal positioning and tuning the gravimeter’s stabilized platform for aircraft use.

VERTICAL ATTENUATION OF ANOMALIES IN AIRBORNE GRAVIMETRY

Geophysics ◽  
1971 ◽  
Vol 36 (5) ◽  
pp. 867-877 ◽  
Author(s):  
Sigmund Hammer
Keyword(s):  
Three Dimensional ◽  
Signal Strength ◽  
Airborne Gravity ◽  
Airborne Gravimetry ◽  
Anomaly Field ◽  
Different Types ◽  
Order Of Magnitude ◽  
The Difference ◽  
Minimum Points ◽  
Derivative Order

Analysis of components of the gravity anomaly field from basic one, two, and three‐dimensional masses demonstrates that all components of the same derivative order attenuate with flight elevation at the same rate for a given type of anomaly. Different types of anomalies attenuate with significantly different rates. The signal strength of an anomaly component is conveniently defined as the difference between values at adjacent maximum and minimum points along a profile. For a given type of anomaly, the signal strengths of all comparable components are roughly equal, within about half an order of magnitude. Relative attenuations of anticipated signal and terrain noise permit evaluation of favorable and unfavorable prospect areas for airborne gravity exploration. A corollary result is that the tolerance in flight elevation control is orders of magnitude less severe for gradiometer surveying than for airborne gravity surveying. The conclusions are relevant in the choice of the most advantageous component for possible development of airborne gravimetry.

Monitoring the lunar capture of Chang'E-1 satellite by real-time reduction of the instantaneous state vectors

2007 ◽  
Vol 3 (S248) ◽  
pp. 194-195
Author(s):  
L. Guo ◽  
J. L. Li ◽  
S. B. Qiao ◽  
F. Tian
Keyword(s):  
Data Processing ◽  
Real Time ◽  
Practical Method ◽  
The Real ◽  
Data Processing Software ◽  
Orbit Evolution ◽  
Processing Software ◽  
Time Reduction

AbstractBased on our independently developed data processing software, the real-time reduction of the instantaneous state vectors of satellite during the maneuver stage near to perilune is analyzed via experimental observations. Results show that it is a quick and practical method to monitor the orbit evolution and the lunar capture of Chang'E-1 satellite.

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