Reply by the authors to Nobes, Schneider, and Hodgson

Geophysics ◽  
1987 ◽  
Vol 52 (10) ◽  
pp. 1439-1441
Author(s):  
D. Han ◽  
A. Nur ◽  
D. Morgan
Keyword(s):  
Physical Model ◽  
Physical Property ◽  
Average Model

We agree with Nobes et al. that our own bias, like theirs, is that “If at all possible equations relating one physical property to another should be based on some physical model,” but in addition we believe also that such a model must be correct, or at least physically sound. It is on the issue of the soundness of the traveltime average model that we fundamentally disagree with Nobes et al.

On: “Effects of porosity and clay content on wave velocities in sandstones” by D. Han, A. Nur, and D. Morgan (GEOPHYSICS, 51, 2093–2107, November 1986”.

Geophysics ◽  
1987 ◽  
Vol 52 (10) ◽  
pp. 1439-1439 ◽  
Author(s):  
David C. Nobes ◽  
George Schneider ◽  
Stephen Hodgson
Keyword(s):  
Physical Model ◽  
Seismic Velocity ◽  
Statistical Significance ◽  
Physical Property ◽  
Clay Content ◽  
Related Question ◽  
Wave Velocities ◽  
Physical Principles

At the outset, we must declare our philosophical bias: we believe that, if at all possible, equations relating one physical property to another should be based on some physical model. If there are two equations that can be said to relate one property to another equally well, within statistical bounds, then the equation that is based on physical principles is preferable. We acknowledge that the relationships among in this case, porosity, clay content, and seismic velocity are not always clear or easily tested, and we appreciate the efforts of Han et al. However, we have a comment and a related question regarding the statistical significance of their results.

Prediction of Annulus Pressure Gradients in Pumping Wells

1980 ◽  
Vol 102 (4) ◽  
pp. 181-183 ◽  
Author(s):  
Zˇ. Schmidt ◽  
J. P. Brill ◽  
H. D. Beggs
Keyword(s):  
Experimental Data ◽  
Pressure Gradient ◽  
Physical Model ◽  
Physical Property ◽  
Pressure Gradients ◽  
Concentric Annulus ◽  
Pumping Wells ◽  
Adequate Representation ◽  
Gas Bubbling ◽  
S Curve

Experimental data on pressure gradients were obtained for gas bubbling through static liquids in various concentric annulus configurations with eight different liquids. Although a definite liquid physical property effect exists, the Gilbert “S” curve gave an adequate representation of the data. A more accurate correlation was developed, together with a physical model that separates hydrostatic and friction components of the pressure gradient.

A physical model of shear‐wave propagation in a transversely isotropic solid

Geophysics ◽  
1994 ◽  
Vol 59 (3) ◽  
pp. 484-487 ◽  
Author(s):  
Chih‐Hsiung Chang ◽  
G. H. F. Gardner ◽  
John A. McDonald
Keyword(s):  
Wave Propagation ◽  
Physical Model ◽  
Shear Wave ◽  
Seismic Anisotropy ◽  
Sedimentary Rocks ◽  
Physical Property ◽  
Transversely Isotropic ◽  
Velocity Variation ◽  
Common Phenomenon ◽  
Isotropic Solid

It is now understood that seismic anisotropy is a comparatively common phenomenon in sedimentary layers. The elastic properties of most sedimentary rocks have been shown to be anisotropic. (Anisotropy means that the physical property of the material is a function of the measuring direction). Seismologists are generally concerned with velocity variation with the direction of propagation.

Scanning tunneling microscopy and atomic force microscopy: New tools for biology

1989 ◽  
Vol 47 ◽  
pp. 778-779
Author(s):  
CE Bracker ◽  
P. K. Hansma
Keyword(s):  
Physical Property ◽  
Scanning Probe ◽  
Scanning Tunneling ◽  
Small Scale ◽  
Tunneling Microscopy ◽  
Force Microscopy ◽  
New Family ◽  
Small Probe ◽  
Atomic Force ◽  
Transmission Electron

A new family of scanning probe microscopes has emerged that is opening new horizons for investigating the fine structure of matter. The earliest and best known of these instruments is the scanning tunneling microscope (STM). First published in 1982, the STM earned the 1986 Nobel Prize in Physics for two of its inventors, G. Binnig and H. Rohrer. They shared the prize with E. Ruska for his work that had led to the development of the transmission electron microscope half a century earlier. It seems appropriate that the award embodied this particular blend of the old and the new because it demonstrated to the world a long overdue respect for the enormous contributions electron microscopy has made to the understanding of matter, and at the same time it signalled the dawn of a new age in microscopy. What we are seeing is a revolution in microscopy and a redefinition of the concept of a microscope.Several kinds of scanning probe microscopes now exist, and the number is increasing. What they share in common is a small probe that is scanned over the surface of a specimen and measures a physical property on a very small scale, at or near the surface. Scanning probes can measure temperature, magnetic fields, tunneling currents, voltage, force, and ion currents, among others.

A photoelectron microscope study of surfaces

1989 ◽  
Vol 47 ◽  
pp. 10-11
Author(s):  
W. Engel ◽  
M. Kordesch ◽  
A. M. Bradshaw ◽  
E. Zeitler
Keyword(s):  
Electron Microscopy ◽  
High Pressure ◽  
Field Strength ◽  
Uv Light ◽  
Physical Property ◽  
Photon Flux ◽  
Mercury Lamp ◽  
Object Surface ◽  
The Sixties ◽  
Physical Features

Photoelectron microscopy is as old as electron microscopy itself. Electrons liberated from the object surface by photons are utilized to form an image that is a map of the object's emissivity. This physical property is a function of many parameters, some depending on the physical features of the objects and others on the conditions of the instrument rendering the image.The electron-optical situation is tricky, since the lateral resolution increases with the electric field strength at the object's surface. This, in turn, leads to small distances between the electrodes, restricting the photon flux that should be high for the sake of resolution.The electron-optical development came to fruition in the sixties. Figure 1a shows a typical photoelectron image of a polycrystalline tantalum sample irradiated by the UV light of a high-pressure mercury lamp.

Investigating the Multimodal Nature of Human Communication

2009 ◽  
Vol 23 (2) ◽  
pp. 63-76 ◽  
Author(s):  
Silke Paulmann ◽  
Sarah Jessen ◽  
Sonja A. Kotz
Keyword(s):  
Visual Information ◽  
Empirical Studies ◽  
Physical Property ◽  
Event Related Potentials ◽  
Accurate Information ◽  
Human Communication ◽  
Channel Condition ◽  
Prosodic Cues ◽  
Early Processing ◽  
Related Potentials

The multimodal nature of human communication has been well established. Yet few empirical studies have systematically examined the widely held belief that this form of perception is facilitated in comparison to unimodal or bimodal perception. In the current experiment we first explored the processing of unimodally presented facial expressions. Furthermore, auditory (prosodic and/or lexical-semantic) information was presented together with the visual information to investigate the processing of bimodal (facial and prosodic cues) and multimodal (facial, lexic, and prosodic cues) human communication. Participants engaged in an identity identification task, while event-related potentials (ERPs) were being recorded to examine early processing mechanisms as reflected in the P200 and N300 component. While the former component has repeatedly been linked to physical property stimulus processing, the latter has been linked to more evaluative “meaning-related” processing. A direct relationship between P200 and N300 amplitude and the number of information channels present was found. The multimodal-channel condition elicited the smallest amplitude in the P200 and N300 components, followed by an increased amplitude in each component for the bimodal-channel condition. The largest amplitude was observed for the unimodal condition. These data suggest that multimodal information induces clear facilitation in comparison to unimodal or bimodal information. The advantage of multimodal perception as reflected in the P200 and N300 components may thus reflect one of the mechanisms allowing for fast and accurate information processing in human communication.

Effect of Electrolyte Compositions on the Physical Property and Surface Morphology of Copper Foil

2010 ◽  
Vol 48 (10) ◽  
pp. 951-956 ◽  
Author(s):  
Tae-Gyu Woo ◽  
Il-Song Park ◽  
Woo-Yong Jeon ◽  
Eun-Kwang Park ◽  
Kwang-Hee Jung ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Copper Foil ◽  
Physical Property

EXPERIMENTAL STUDIES OF CAR PROPERTIES ON A PHYSICAL MODEL

2019 ◽  
pp. 10-16
Author(s):  
Oleksii Timkov ◽  
Dmytro Yashchenko ◽  
Volodymyr Bosenko
Keyword(s):  
Mathematical Model ◽  
Remote Control ◽  
Physical Model ◽  
Model Experiment ◽  
Experimental Studies ◽  
Electrical Energy ◽  
Short Term ◽  
Motor Current ◽  
Memory Card ◽  
The Mathematical Model

The article deals with the development of a physical model of a car equipped with measuring, recording and remote control equipment for experimental study of car properties. A detailed description of the design of the physical model and of the electronic modules used is given, links to application libraries and the code of the first part of the program for remote control of the model are given. Atmega microcontroller on the Arduino Uno platform was used to manage the model and register the parameters. When moving the car on the memory card saved such parameters as speed, voltage on the motor, current on the motor, the angle of the steered wheel, acceleration along three coordinate axes are recorded. Use of more powerful microcontrollers will allow to expand the list of the registered parameters of movement of the car. It is possible to measure the forces acting on the elements of the car and other parameters. In the future, it is planned to develop a mathematical model of motion of the car and check its adequacy in conducting experimental studies on maneuverability on the physical model. In addition, it is possible to conduct studies of stability and consumption of electrical energy. The physical model allows to quickly change geometric dimensions and mass parameters. In the study of highway trains, this approach will allow to investigate the various layout schemes of highway trains in the short term. It is possible to make two-axle road trains and saddle towed trains, three-way hitched trains of different layout. The results obtained will allow us to improve not only the mathematical model, but also the experimental physical model, and move on to further study the properties of hybrid road trains with an active trailer link. This approach allows to reduce material and time costs when researching the properties of cars and road trains. Keywords: car, physical model, experiment, road trains, sensor, remote control, maneuverability, stability.

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