ELIMINATION OF SEISMIC GHOST REFLECTIONS BY MEANS OF A LINEAR FILTER

Geophysics ◽  
1960 ◽  
Vol 25 (1) ◽  
pp. 130-140 ◽  
Author(s):  
J. P. Lindsey
Keyword(s):  
Autocorrelation Function ◽  
Measurement Technique ◽  
Amplitude Ratio ◽  
Linear Filter ◽  
Record Time ◽  
Principal Assumption ◽  
Made In

A technique is described for elimination of ghost reflections on magnetically recorded seismograph records by means of a linear filter. The application of this filter does not alter the character of primary reflections although eliminating the ghost reflections. The principal assumption made in the development of the technique is that the effect of AGC in altering the amplitude ratio of primary and ghost reflections is uniform for all record time. A realization of the required filter is given and a measurement technique is outlined for detecting the existence of ghost reflections based on the autocorrelation function of the seismograph trace.

scholarly journals Vaccines made in record time

2020 ◽  
Vol 248 (3313-3314) ◽  
pp. 21
Author(s):  
Catherine de Lange
Keyword(s):  
Record Time ◽  
Made In

scholarly journals National Physical Laboratory Radiocarbon Measurements VII

Radiocarbon ◽  
1970 ◽  
Vol 12 (1) ◽  
pp. 181-186 ◽  
Author(s):  
W. J. Callow ◽  
Geraldine I. Hassall
Keyword(s):  
Measurement Technique ◽  
National Physical Laboratory ◽  
Term Stability ◽  
Long Term Stability ◽  
Physical Laboratory ◽  
Made In

The following list comprises measurements made since those reported in Radiocarbon, 1969, v. 11, p. 130–136. No changes have been made in measurement technique or in the method of calculating the results described in Radiocarbon, 1965, v. 7, p. 156–161. It was necessary during 1968 to replace all the geiger counters used in the anti-coincidence rings, but the long term stability of background and standard count rates implicit in the use of a 20-week rolling mean has been maintained.

scholarly journals National Physical Laboratory Radiocarbon Measurements V

Radiocarbon ◽  
1968 ◽  
Vol 10 (1) ◽  
pp. 115-118 ◽  
Author(s):  
W. J. Callow ◽  
Geraldine I. Hassall
Keyword(s):  
Measurement Technique ◽  
National Physical Laboratory ◽  
Physical Laboratory ◽  
Made In

The following list comprises measurements made since those reported in NPL IV.No changes have been made in measurement technique or in the method of calculating results

scholarly journals National Physical Laboratory Radiocarbon Measurements VI

Radiocarbon ◽  
1969 ◽  
Vol 11 (01) ◽  
pp. 130-136 ◽  
Author(s):  
W. J. Callow ◽  
Geraldine I. Hassall
Keyword(s):  
Measurement Technique ◽  
National Physical Laboratory ◽  
Physical Laboratory ◽  
Made In

The following list comprises measurements made since those reported in NPL V.No changes have been made in measurement technique or in the method of calculating results described in NPL III.

scholarly journals Dynamic Measurements with the Bicone Interfacial Shear Rheometer: Numerical Bench-Marking of Flow Field-Based Data Processing

2018 ◽  
Vol 2 (4) ◽  
pp. 69 ◽  
Author(s):  
Pablo Sánchez-Puga ◽  
Javier Tajuelo ◽  
Juan Pastor ◽  
Miguel Rubio
Keyword(s):  
Flow Field ◽  
Stokes Equations ◽  
Amplitude Ratio ◽  
Numerical Procedure ◽  
Complex Viscosity ◽  
Detailed Comparison ◽  
Interfacial Shear ◽  
Navier Stokes ◽  
Navier Stokes Equations ◽  
Made In

Flow field-based methods are becoming increasingly popular for the analysis of interfacial shear rheology data. Such methods take properly into account the subphase drag by solving the Navier–Stokes equations for the bulk phase flows, together with the Boussinesq–Scriven boundary condition at the fluid–fluid interface and the probe equation of motion. Such methods have been successfully implemented on the double wall-ring (DWR), the magnetic rod (MR), and the bicone interfacial shear rheometers. However, a study of the errors introduced directly by the numerical processing is still lacking. Here, we report on a study of the errors introduced exclusively by the numerical procedure corresponding to the bicone geometry at an air–water interface. In our study, we set an input value of the complex interfacial viscosity, and we numerically obtained the corresponding flow field and the complex amplitude ratio for the probe motion. Then, we used the standard iterative procedure to obtain the calculated complex viscosity value. A detailed comparison of the set and calculated complex viscosity values was made in wide ranges of the three parameters herein used, namely the real and imaginary parts of the complex interfacial viscosity and the frequency. The observed discrepancies yield a detailed landscape of the numerically-introduced errors.

Moderately Large Amplitude Plate Vibration Modes

1980 ◽  
Vol 102 (2) ◽  
pp. 405-411
Author(s):  
J. C. Kennedy
Keyword(s):  
Amplitude Ratio ◽  
Analog Computer ◽  
System Response ◽  
Vibration Modes ◽  
Simply Supported ◽  
Plate Equations ◽  
Simplifying Assumptions ◽  
Versus Amplitude ◽  
Ratio Versus ◽  
Made In

The influence of moderately large amplitudes on the frequency of vibration for the fundamental mode and some higher modes of the simply supported rectangular plate is established. Plate equations that are valid for the moderately large motions are programmed for solution on the analog computer. The effect of eliminating in-plane motions and accelerations on the system response is quantitatively established. It is shown that frequency ratio versus amplitude ratio is aspect ratio dependent and the study shows how simplifying assumptions made in some previous studies affect this dependence.

Thermal Conductivity and Thermal Diffusivity of Biomaterials: A Simultaneous Measurement Technique

1977 ◽  
Vol 99 (3) ◽  
pp. 148-154 ◽  
Author(s):  
T. A. Balasubramaniam ◽  
H. F. Bowman
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Measurement Technique ◽  
Thermal Model ◽  
In Vitro Measurements ◽  
Made In

A technique is presented for the simultaneous determination of thermal conductivity and thermal diffusivity of biomaterials. Measurements are derived from the transient power supplied to a thermistor probe operated in a self-heated mode. The thermal properties are extracted through the use of an appropriate thermal model. Thermal conductivity is determined through a simple algebraic equation. Thermal diffusivity is determined from a convenient set of nondimensionalized curves. The technique can be used in vivo and in vitro. Measurements can be made in sample volumes of less than 1 cc in less than 30 s.

Spectrophotometric measurements of objective-prism spectra

1966 ◽  
Vol 24 ◽  
pp. 118-119
Author(s):  
Th. Schmidt-Kaler
Keyword(s):  
Progress Report ◽  
Two Dimensional ◽  
Objective Prism ◽  
Made In

I should like to give you a very condensed progress report on some spectrophotometric measurements of objective-prism spectra made in collaboration with H. Leicher at Bonn. The procedure used is almost completely automatic. The measurements are made with the help of a semi-automatic fully digitized registering microphotometer constructed by Hög-Hamburg. The reductions are carried out with the aid of a number of interconnected programmes written for the computer IBM 7090, beginning with the output of the photometer in the form of punched cards and ending with the printing-out of the final two-dimensional classifications.

Surface Structure in Microtomed Sections Caused by Glass and Diamond Knives

1971 ◽  
Vol 29 ◽  
pp. 456-457
Author(s):  
J. Temple Black ◽  
William G. Boldosser
Keyword(s):  
Plastic Deformation ◽  
Epoxy Resin ◽  
Carbon Coating ◽  
Surface Damage ◽  
Body Angle ◽  
Normal Manner ◽  
Bottom Side ◽  
Cutting Direction ◽  
Made In ◽  
Diamond Knife

Ultramicrotomy produces plastic deformation in the surfaces of microtomed TEM specimens which can not generally be observed unless special preparations are made. In this study, a typical biological composite of tissue (infundibular thoracic attachment) infiltrated in the normal manner with an embedding epoxy resin (Epon 812 in a 60/40 mixture) was microtomed with glass and diamond knives, both with 45 degree body angle. Sectioning was done in Portor Blum Mt-2 and Mt-1 microtomes. Sections were collected on formvar coated grids so that both the top side and the bottom side of the sections could be examined. Sections were then placed in a vacuum evaporator and self-shadowed with carbon. Some were chromium shadowed at a 30 degree angle. The sections were then examined in a Phillips 300 TEM at 60kv.Carbon coating (C) or carbon coating with chrom shadowing (C-Ch) makes in effect, single stage replicas of the surfaces of the sections and thus allows the damage in the surfaces to be observable in the TEM. Figure 1 (see key to figures) shows the bottom side of a diamond knife section, carbon self-shadowed and chrom shadowed perpendicular to the cutting direction. Very fine knife marks and surface damage can be observed.

Iron storage sites in the myocardium as revealed by cytohistochemistry

1988 ◽  
Vol 46 ◽  
pp. 394-395
Author(s):  
M. Ashraf ◽  
F. Thompson ◽  
S. Miki ◽  
P. Srivastava
Keyword(s):  
Cardiac Tissue ◽  
Coronary Perfusion ◽  
Intracellular Iron ◽  
Ether Anesthesia ◽  
Intense Staining ◽  
Iron Storage ◽  
Thin Sections ◽  
Rat Hearts ◽  
Cacodylate Buffer ◽  
Made In

Iron is believed to play an important role in the pathogenesis of ischemic injury. However, the sources of intracellular iron in myocytes are not yet defined. In this study we have attempted to localize iron at various cellular sites of the cardiac tissue with the ferrocyanide technique.Rat hearts were excised under ether anesthesia. They were fixed with coronary perfusion with 3% buffered glutaraldehyde made in 0.1 M cacodylate buffer pH 7.3. Sections, 60 μm in thickness, were cut on a vibratome and were incubated in the medium containing 500 mg of potassium ferrocyanide in 49.5 ml H2O and 0.5 ml concentrated HC1 for 30 minutes at room temperature. Following rinses in the buffer, tissues were dehydrated in ethanol and embedded in Spurr medium.The examination of thin sections revealed intense staining or reaction product in peroxisomes (Fig. 1).

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