On: “High‐resolution common‐depth point profiling: Field acquisition parameter design,” by R. Knapp and D. Steeples (GEOPHYSICS, 51, 283–294, February, 1986).

Geophysics ◽  
1986 ◽  
Vol 51 (10) ◽  
pp. 2011-2011 ◽  
Author(s):  
W. Harry Mayne
Keyword(s):  
High Resolution ◽  
Parameter Design ◽  
Common Depth Point

I have read your article with interest and congratulate you on an excellent overview of this topic. There are a couple of points on which I would like to comment, however.

To: “High‐resolution common‐depth‐point reflection profiling: Field acquisition parameter design,” by R. W. Knapp and D. W. Steeples, which appeared in February 1986, GEOPHYSICS, p. 283–294

Geophysics ◽  
1986 ◽  
Vol 51 (7) ◽  
pp. 1519-1519
Keyword(s):  
High Resolution ◽  
Parameter Design ◽  
Maximum Frequency ◽  
Common Depth Point ◽  
Point Reflection

The following errors have been detected. p. 288, left column, 3rd paragraph: Change (Figure 4, Knapp and Steeples, 1986, this issue) to (Figure 3, Knapp and Steeples, 1986, this issue). p. 288, right column, 3rd complete paragraph, 3rd sentence: Change “…when the length of the array is equal to about one‐fourth the apparent surface wavelength…” to “…when the length of the array is equal to about one‐half the apparent surface wavelength…”. Next line, change “ [Formula: see text]” to “[Formula: see text]”. Next line, change “[Formula: see text].” to “[Formula: see text]”. Next line, change “one‐fourth” to “one‐half”. Next 2 equations, change “L ⩽ .25…” to “L ⩽ .5…” and [Formula: see text]…” to “[Formula: see text]…”. p. 289, left column: Change [Formula: see text] to [Formula: see text] Following paragraph, 4th line: Change “.75 m.” to “1.4 m.”; and change “When the maximum frequency value approaches and exceeds 100 Hz (apparent frequency equal to about 70 Hz),…” to “When the maximum frequency value approaches and exceeds 200 Hz (apparent frequency equal to about 140 Hz),…”.

Multiple attenuation with 3D high-order high-resolution parabolic Radon transform using lower frequency constraints

Geophysics ◽  
2020 ◽  
Vol 85 (3) ◽  
pp. V317-V328
Author(s):  
Jitao Ma ◽  
Guoyang Xu ◽  
Xiaohong Chen ◽  
Xiaoliu Wang ◽  
Zhenjiang Hao
Keyword(s):  
High Resolution ◽  
Radon Transform ◽  
Seismic Data ◽  
Computational Cost ◽  
Real Data ◽  
Multiple Model ◽  
Multiple Attenuation ◽  
Common Depth Point ◽  
Frequency Constraint ◽  
Parabolic Radon Transform

The parabolic Radon transform is one of the most commonly used multiple attenuation methods in seismic data processing. The 2D Radon transform cannot consider the azimuth effect on seismic data when processing 3D common-depth point gathers; hence, the result of applying this transform is unreliable. Therefore, the 3D Radon transform should be applied. The theory of the 3D Radon transform is first introduced. To address sparse sampling in the crossline direction, a lower frequency constraint is introduced to reduce spatial aliasing and improve the resolution of the Radon transform. An orthogonal polynomial transform, which can fit the amplitude variations in different parabolic directions, is combined with the dealiased 3D high-resolution Radon transform to account for the amplitude variations with offset of seismic data. A multiple model can be estimated with superior accuracy, and improved results can be achieved. Synthetic and real data examples indicate that even though our method comes at a higher computational cost than existing techniques, the developed approach provides better attenuation of multiples for 3D seismic data with amplitude variations.

scholarly journals Parameter Design and Performance Evaluation of a Large-Swath and High-Resolution Space Camera

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 4106
Author(s):  
Yingying Sun ◽  
Peng Rao ◽  
Tingliang Hu
Keyword(s):  
High Resolution ◽  
Design Method ◽  
Grid Point ◽  
Parameter Design ◽  
Weighting Method ◽  
System Parameters ◽  
The Monte Carlo Method ◽  
Repeated Observation ◽  
Large Width ◽  
And Performance

A rotary-scan space camera with an area sensor can achieve large width and high-resolution imaging. Designing system parameters properly is important for the application of the rotary-scan space camera. We model the swath, resolution, and overlap rate between frames for such a camera. An optimum algorithm combining the linear weighting method and the Monte Carlo method for system parameter design is proposed based on the model. Then, the performance of the designed system is evaluated using the grid point method. The designed systems can achieve swaths of more than 1000 km and less than 1 m resolution without leakage during the imaging. In the evaluation, the designed system can cover 82.13% of the observation region at the height of 500 km in 6.5 min, and the average repeated observation frequency is 3.26 times per 118 s. The design method is simple and effective in the initial design of the rotary-scan space camera’s system parameters. The system designed can provide “no-leakage and wide coverage by quick scan” and “high-frequency repeated observation over a long visibility period.” This will greatly improve earth observation ability in wide-area search and rescue missions.

scholarly journals High‐resolution common‐depth‐point seismic reflection profiling: Instrumentation

Geophysics ◽  
1986 ◽  
Vol 51 (2) ◽  
pp. 276-282 ◽  
Author(s):  
Ralph W. Knapp ◽  
Don W. Steeples
Keyword(s):  
High Resolution ◽  
High Frequency ◽  
Dynamic Range ◽  
Low Frequency ◽  
Main Element ◽  
Critical Element ◽  
Frequency Signal ◽  
High Frequency Signal ◽  
Common Depth Point ◽  
Seismic Recording

Seismic recording hardware must be a deliberately designed system to extract and record high‐resolution information faithfully. The single most critical element of this system is the detector. The detector chosen must be capable of faithfully generating the passband expected and furthermore, must be carefully coupled to the ground. Another important factor is to shape the energy passband so that it is as flat and broad as possible. This involves low‐cut filtering of the data before A/D conversion so the magnitude of the low‐frequency signal does not swamp the high‐frequency signal. The objective is to permit boosting the magnitude of the high‐frequency signals to fill a significant number of bits of the digital word. Judicious use of a low‐cut filter is the main element of this step, although detector selection is also a factor because detectors have a −6 dB/octave velocity response at frequencies less than the resonant frequency of the detector. Finally, recording instrument quality must be good. Amplifiers should have low system noise, large dynamic range, and precision of 12 or more bits.

Observations of the spatial structure of interstellar hydrogen

1967 ◽  
Vol 31 ◽  
pp. 45-46
Author(s):  
Carl Heiles
Keyword(s):  
High Resolution ◽  
Spatial Structure ◽  
Velocity Dispersion ◽  
Temperature Variations

High-resolution 21-cm line observations in a region aroundlII= 120°,b11= +15°, have revealed four types of structure in the interstellar hydrogen: a smooth background, large sheets of density 2 atoms cm-3, clouds occurring mostly in groups, and ‘Cloudlets’ of a few solar masses and a few parsecs in size; the velocity dispersion in the Cloudlets is only 1 km/sec. Strong temperature variations in the gas are in evidence.

Combining integrated systems-biology approaches with intervention-based experimental design provides a higher-resolution path forward for microbiome research

2019 ◽  
Vol 42 ◽  
Author(s):  
J. Alfredo Blakeley-Ruiz ◽  
Carlee S. McClintock ◽  
Ralph Lydic ◽  
Helen A. Baghdoyan ◽  
James J. Choo ◽  
...  
Keyword(s):  
Systems Biology ◽  
High Resolution ◽  
Experimental Design ◽  
Integrated Systems ◽  
Microbiome Research ◽  
Constructive Criticism

Abstract The Hooks et al. review of microbiota-gut-brain (MGB) literature provides a constructive criticism of the general approaches encompassing MGB research. This commentary extends their review by: (a) highlighting capabilities of advanced systems-biology “-omics” techniques for microbiome research and (b) recommending that combining these high-resolution techniques with intervention-based experimental design may be the path forward for future MGB research.

Very High Resolution Analysis of the Dynamics of a Coronal Plasmoid

1994 ◽  
Vol 144 ◽  
pp. 593-596
Author(s):  
O. Bouchard ◽  
S. Koutchmy ◽  
L. November ◽  
J.-C. Vial ◽  
J. B. Zirker
Keyword(s):  
High Resolution ◽  
Solar Eclipse ◽  
Total Solar Eclipse ◽  
Field Of View ◽  
Small Field ◽  
High Resolution Analysis ◽  
Ccd Observations ◽  
Resolution Analysis ◽  
Very High ◽  
Small Field Of View

AbstractWe present the results of the analysis of a movie taken over a small field of view in the intermediate corona at a spatial resolution of 0.5“, a temporal resolution of 1 s and a spectral passband of 7 nm. These CCD observations were made at the prime focus of the 3.6 m aperture CFHT telescope during the 1991 total solar eclipse.

FeXIV Line Emission Polarization of the July 11, 1991 Solar Corona

1994 ◽  
Vol 144 ◽  
pp. 541-547
Author(s):  
J. Sýkora ◽  
J. Rybák ◽  
P. Ambrož
Keyword(s):  
High Resolution ◽  
Solar Corona ◽  
Emission Line ◽  
Solar Eclipse ◽  
White Light ◽  
Preliminary Analysis ◽  
Line Emission ◽  
Total Solar Eclipse ◽  
Degree Of Polarization ◽  
High Resolution Images

AbstractHigh resolution images, obtained during July 11, 1991 total solar eclipse, allowed us to estimate the degree of solar corona polarization in the light of FeXIV 530.3 nm emission line and in the white light, as well. Very preliminary analysis reveals remarkable differences in the degree of polarization for both sets of data, particularly as for level of polarization and its distribution around the Sun’s limb.

Microcalorimeters for X-Ray Spectroscopy

1988 ◽  
Vol 102 ◽  
pp. 41
Author(s):  
E. Silver ◽  
C. Hailey ◽  
S. Labov ◽  
N. Madden ◽  
D. Landis ◽  
...  
Keyword(s):  
High Resolution ◽  
High Efficiency ◽  
Thermal Response ◽  
Low Noise ◽  
High Resolution Spectroscopy ◽  
Superconducting Transition ◽  
Sapphire Substrates ◽  
Laboratory Plasmas ◽  
Adiabatic Demagnetization ◽  
Theoretical Predictions

The merits of microcalorimetry below 1°K for high resolution spectroscopy has become widely recognized on theoretical grounds. By combining the high efficiency, broadband spectral sensitivity of traditional photoelectric detectors with the high resolution capabilities characteristic of dispersive spectrometers, the microcalorimeter could potentially revolutionize spectroscopic measurements of astrophysical and laboratory plasmas. In actuality, however, the performance of prototype instruments has fallen short of theoretical predictions and practical detectors are still unavailable for use as laboratory and space-based instruments. These issues are currently being addressed by the new collaborative initiative between LLNL, LBL, U.C.I., U.C.B., and U.C.D.. Microcalorimeters of various types are being developed and tested at temperatures of 1.4, 0.3, and 0.1°K. These include monolithic devices made from NTD Germanium and composite configurations using sapphire substrates with temperature sensors fabricated from NTD Germanium, evaporative films of Germanium-Gold alloy, or material with superconducting transition edges. A new approache to low noise pulse counting electronics has been developed that allows the ultimate speed of the device to be determined solely by the detector thermal response and geometry. Our laboratory studies of the thermal and resistive properties of these and other candidate materials should enable us to characterize the pulse shape and subsequently predict the ultimate performance. We are building a compact adiabatic demagnetization refrigerator for conveniently reaching 0.1°K in the laboratory and for use in future satellite-borne missions. A description of this instrument together with results from our most recent experiments will be presented.

Radiation Damage, Contrast and Statistics in High Resolution Biological Electron Microscopy

1970 ◽  
Vol 28 ◽  
pp. 260-261
Author(s):  
Robert M. Glaeser
Keyword(s):  
High Resolution ◽  
Particle Flux ◽  
Unit Area ◽  
Signal To Noise ◽  
Resolution Image ◽  
High Resolution Image ◽  
Pass Through ◽  
Counting Statistics ◽  
The Relationship ◽  
Picture Element

It is well known that a large flux of electrons must pass through a specimen in order to obtain a high resolution image while a smaller particle flux is satisfactory for a low resolution image. The minimum particle flux that is required depends upon the contrast in the image and the signal-to-noise (S/N) ratio at which the data are considered acceptable. For a given S/N associated with statistical fluxtuations, the relationship between contrast and “counting statistics” is s131_eqn1, where C = contrast; r2 is the area of a picture element corresponding to the resolution, r; N is the number of electrons incident per unit area of the specimen; f is the fraction of electrons that contribute to formation of the image, relative to the total number of electrons incident upon the object.

Sign in / Sign up

Export Citation Format

Share Document