Determination of the signature of a dynamite source using source scaling, Part 2: Experiment

Geophysics ◽  
1993 ◽  
Vol 58 (8) ◽  
pp. 1183-1194 ◽  
Author(s):  
Anton Ziolkowski ◽  
Karel Bokhorst
Keyword(s):  
Seismic Data ◽  
Scaling Law ◽  
Estimation Methods ◽  
Acceptable Error ◽  
Test Charge ◽  
Source Scaling ◽  
Test Record ◽  
Seismic Data Acquisition ◽  
Made In

In April 1990 we performed an experiment in the Netherlands to test the theory of the determination of the signature of a dynamite source using the scaling law. The theory says that the source signature may be determined from the recorded seismic data using two shots of different charge size at the shotpoint; we used 125 g and 500 g charges. The theory was put at risk with a 250-g test charge at each shotpoint. According to the theory, the test record should be different from the other two and, apart from the noise, should be predictable from them. This experiment was repeated 95 times at approximately 50 m shotpoint intervals, using a 240-channel recording system. The results corroborate the theory within an acceptable error. The second‐derivative of the volume injection function was extracted as the source signature; it varied slightly from shot to shot and was minimum phase. This new method of seismic data acquisition allows the signature of the dynamite source to be obtained from the data, uncontaminated by the earth, and avoids the assumptions that must be made in statistical wavelet estimation methods. If there is good shot‐to‐shot repeatability, the second shot is only needed occasionally for calibration.

Determination of the signature of a dynamite source using source scaling, Part 1: Theory

Geophysics ◽  
1993 ◽  
Vol 58 (8) ◽  
pp. 1174-1182 ◽  
Author(s):  
Anton Ziolkowski
Keyword(s):  
Impulse Response ◽  
Seismic Data ◽  
Scaling Law ◽  
Cube Root ◽  
The Earth ◽  
Shot Point ◽  
Source Scaling ◽  
Seismic Data Acquisition ◽  
Injection Function

It is normally impossible to measure the source signature in land seismic data acquisition with a dynamite source, because it is normally impossible to separate the incident field from the scattered field. Nevertheless, in any serious attempt to invert the seismic data, it is essential to know the source signature; for the dynamite source this is the volume injection function. The problem can be solved by using two different shots at each shot point and relating the source signatures by the source scaling law, which follows from the invariance of the medium parameters with the size of the charge. The volume injection function of the larger shot is an amplified and stretched version of that of the smaller shot, the amplification factor being equal to the ratio of the charge masses and the time stretch factor being equal to the cube‐root of this ratio. At a given receiver, the response to one shot is a convolution of the source signature with the impulse response of the earth, plus noise. The two shots and the scaling law give three independent equations relating the three unknowns: the two source signatures and the impulse response of the earth (plus noise). This theory may be put at risk in a physical experiment which requires a third shot at the same shot point, using a known mass of dynamite, different from the first two. The resulting shot record should be different from the first two and, apart from the noise, should be predictable from them.

scholarly journals Evapotranspiração da cultura da cebola

2015 ◽  
Vol 10 (4) ◽  
pp. 58
Author(s):  
G. M. Oliveira ◽  
M. W. Silva ◽  
M. N. Daamen ◽  
E. C. S. Cavalcante ◽  
M. M. V. B. R. Leitão
Keyword(s):  
Social Sciences ◽  
Reference Evapotranspiration ◽  
Irrigation System ◽  
The State ◽  
Estimation Methods ◽  
Crop Evapotranspiration ◽  
Experimental Field ◽  
Evapotranspiration Estimation ◽  
Made In

<p><span>A determinação da quantidade de água necessária para as culturas é um dos principais fatores para o correto planejamento, dimensionamento e manejo de qualquer sistema de irrigação. O presente trabalho teve como objetivo, comparar medida da evapotranspiração da cultura (ETc) da cebola com estimativa obtida a partir da evapotranspiração de referência (ETo) determinada por diferentes métodos e Kc proposto na literatura. O experimento foi conduzido no campo experimental do Departamento de Tecnologia e Ciências Sociais da Universidade do Estado da Bahia - UNEB, em Juazeiro, no período de junho a setembro de 2011. As medidas da ETc foram obtidas em evapotranspirômetros e as estimativas, a partir de ETo determinada pelos métodos: Penman-Monteith (padrão FAO), Penman-Monteith modificado por Villa Nova et al. (2004), Hargreaves &amp; Samani, Makkink e Jensen &amp; Haise e Kc proposto por Marouelli et al. (2005), para a cultura da cebola.<strong> </strong>É fundamental a avaliação de métodos de estimativa da evapotranspiração de referência antes de sua aplicação, pois erros consideráveis podem ser cometidos na determinação da quantidade de água a ser aplicada a uma cultura, o que repercutirá certamente, na produtividade.</span></p><p align="center"><strong><em>Evapotranspiration crop onion</em></strong></p><p><strong>Abstract</strong><strong>: </strong>The determination of the amount of water needed for crops is a major factor for the correct planning, sizing and management of any irrigation system. This study aimed to compare measure of crop evapotranspiration (ETc) onion with estimates obtained from the reference evapotranspiration (ETo) determined by different methods and Kc proposed in the literature. The experiment was conducted in the experimental field of the Department of Technology and Social Sciences, University of the State of Bahia, in Juazeiro, from June to September 2011. The ETc measurements were obtained in evapotranspirometers and estimates, from ETo determined by the methods: Penman-Monteith (FAO standard), Penman-Monteith modified by Villa Nova et al. (2004), Hargreaves &amp; Samani, Makkink and Jensen &amp; Haise and Kc proposed by Marouelli et al. (2005), for the cultivation of onion. It is critical to evaluation of reference evapotranspiration estimation methods before their application because considerable mistakes can be made in determining the amount of water to be applied to a culture, which resonate certainly in productivity.</p><p><span><br /></span></p>

Estimation of source signatures from air guns fired at various depths: A field test of the source scaling law

Geophysics ◽  
2016 ◽  
Vol 81 (3) ◽  
pp. P13-P22 ◽  
Author(s):  
Kjetil E. Haavik ◽  
Martin Landrø
Keyword(s):  
Correction Term ◽  
Near Field ◽  
Scaling Law ◽  
Field Measurements ◽  
Air Gun ◽  
Time Period ◽  
Source Scaling ◽  
Seismic Data Acquisition ◽  
The Difference ◽  
The Given

Recent advances in marine broadband seismic data acquisition have led to a range of new air-gun source configurations. The air-gun arrays have conventionally been kept at a constant depth, but to attenuate the source-side ghost reflection, new source strategies involving multiple source depths have been proposed. The bubble-time period for an air-gun bubble is dependent on, among many parameters, the firing depth. We use quasi near-field measurements of air-gun signatures to validate a version of the well-known source scaling law in which the characteristic bubble-time period is used as the scale. We find that the source scaling law can be used to estimate a source signature from one depth knowing the source signature at a different depth from the same gun. Furthermore, we derive a correction term to the Rayleigh-Willis bubble-time equation to correct for the fact that interaction between the bubble and free surface reduces the bubble-time period. This correction term improves our results significantly for air guns positioned close to the air-water interface. The error between the estimated and measured source signatures is dependent on the difference in source depth. For a depth difference of [Formula: see text], we estimate signatures that have NRMS differences ranging between 5% and 6% from the measured signature at the given depth and between 8% and 12% when the difference is [Formula: see text].

The quantitative comparison of experimental and simulated diffraction contrast images

1995 ◽  
Vol 53 ◽  
pp. 102-103
Author(s):  
Stuart McKernan
Keyword(s):  
Image Processing ◽  
Personal Computer ◽  
Close Agreement ◽  
Quantitative Comparison ◽  
Image Simulation ◽  
Computing Power ◽  
Diffraction Contrast ◽  
Simulated Images ◽  
Made In

For many years the concept of quantitative diffraction contrast experiments might have consisted of the determination of dislocation Burgers vectors using a g.b = 0 criterion from several different 2-beam images. Since the advent of the personal computer revolution, the available computing power for performing image-processing and image-simulation calculations is enormous and ubiquitous. Several programs now exist to perform simulations of diffraction contrast images using various approximations. The most common approximations are the use of only 2-beams or a single systematic row to calculate the image contrast, or calculating the image using a column approximation. The increasing amount of literature showing comparisons of experimental and simulated images shows that it is possible to obtain very close agreement between the two images; although the choice of parameters used, and the assumptions made, in performing the calculation must be properly dealt with. The simulation of the images of defects in materials has, in many cases, therefore become a tractable problem.

Science of Ahangyol and Its Importance for Modern Scientific Thought

2019 ◽  
Vol 10 (5) ◽  
pp. 473-478
Author(s):  
Ahmad Gashamoglu ◽  
Keyword(s):  
Modern Science ◽  
Scientific Basis ◽  
New Paradigm ◽  
Islamic Philosophy ◽  
Scientific Thought ◽  
Religious Books ◽  
Strategic Approach ◽  
Scientific Potential ◽  
Made In

The Article briefly discusses the need for generation of the Science of Ahangyol, and this science’s scientific basis, object and subject, category system, scientific research methods and application options. Ahangyol is a universal science and may be useful in any sphere. It may assist in problem solving in peacemaking process and in many areas such as ecology, economics, politics, culture, management and etc. This science stipulates that any activity and any decision made in the life may only and solely be successful when they comply with harmony principles more, which are the principles of existence and activity of the world. A right strategic approach of the Eastern Philosophy and the Middle Age Islamic Philosophy and scientific thought has an important potential. This strategic approach creates opportunities to also consider irrational factors in addition to rational ones comprehensively in scientific researches. The modern scientific thought contributes to implementation of these opportunities. Ahangyol is a science of determination of ways to achieve harmony in any sphere and of creation of special methods to make progress in these ways through assistance of the modern science. Methods of the System Theory, Mathematics, IT, Astronomy, Physics, Biology, Sociology, Statistics and etc. are more extensively applied. Information is given on some of these methods. Moreover, the Science of Ahangyol, which is a new philosophical worldview and a new paradigm contributes to clarification of metaphysic views considerably and discovery of the scientific potential of religious books.

scholarly journals Determination of Environmental Factors for the Implementation of the Exploitability Index in Industrial Aggregate Mining Using Multi-Criteria Analysis

2021 ◽  
Vol 10 (4) ◽  
pp. 196
Author(s):  
Julio Manuel de Luis-Ruiz ◽  
Benito Ramiro Salas-Menocal ◽  
Gema Fernández-Maroto ◽  
Rubén Pérez-Álvarez ◽  
Raúl Pereda-García
Keyword(s):  
Environmental Factors ◽  
Environmental Factor ◽  
Human Life ◽  
Accurate Estimation ◽  
Analytic Hierarchy ◽  
Main Components ◽  
Hierarchy Process ◽  
Made In

The quality of human life is linked to the exploitation of mining resources. The Exploitability Index (EI) assesses the actual possibilities to enable a mine according to several factors. The environment is one of the most constraining ones, but its analysis is made in a shallow way. This research is focused on its determination, according to a new preliminary methodology that sets the main components of the environmental impact related to the development of an exploitation of industrial minerals and its weighting according to the Analytic Hierarchy Process (AHP). It is applied to the case of the ophitic outcrops in Cantabria (Spain). Twelve components are proposed and weighted with the AHP and an algorithm that allows for assigning a normalized value for the environmental factor to each deposit. Geographic Information Systems (GISs) are applied, allowing us to map a large number of components of the environmental factors. This provides a much more accurate estimation of the environmental factor, with respect to reality, and improves the traditional methodology in a substantial way. It can be established as a methodology for mining spaces planning, but it is suitable for other contexts, and it raises developing the environmental analysis before selecting the outcrop to be exploited.

THE DETERMINATION OF DIGITAL WIENER FILTERS BY MEANS OF GRADIENT METHODS

Geophysics ◽  
1973 ◽  
Vol 38 (2) ◽  
pp. 310-326 ◽  
Author(s):  
R. J. Wang ◽  
S. Treitel
Keyword(s):  
Seismic Data ◽  
High Speed ◽  
Gradient Methods ◽  
Wiener Filter ◽  
Gradient Algorithm ◽  
Rapid Convergence ◽  
True Solution ◽  
Peripheral Device ◽  
Wiener Filters

The normal equations for the discrete Wiener filter are conventionally solved with Levinson’s algorithm. The resultant solutions are exact except for numerical roundoff. In many instances, approximate rather than exact solutions satisfy seismologists’ requirements. The so‐called “gradient” or “steepest descent” iteration techniques can be used to produce approximate filters at computing speeds significantly higher than those achievable with Levinson’s method. Moreover, gradient schemes are well suited for implementation on a digital computer provided with a floating‐point array processor (i.e., a high‐speed peripheral device designed to carry out a specific set of multiply‐and‐add operations). Levinson’s method (1947) cannot be programmed efficiently for such special‐purpose hardware, and this consideration renders the use of gradient schemes even more attractive. It is, of course, advisable to utilize a gradient algorithm which generally provides rapid convergence to the true solution. The “conjugate‐gradient” method of Hestenes (1956) is one of a family of algorithms having this property. Experimental calculations performed with real seismic data indicate that adequate filter approximations are obtainable at a fraction of the computer cost required for use of Levinson’s algorithm.

scholarly journals A revision of daily egg production estimation methods, with application to Atlanto-Iberian sardine. 2. Spatially and environmentally explicit estimates of egg production

2011 ◽  
Vol 68 (3) ◽  
pp. 528-536 ◽  
Author(s):  
Miguel Bernal ◽  
Yorgos Stratoudakis ◽  
Simon Wood ◽  
Leire Ibaibarriaga ◽  
Luis Valdés ◽  
...  
Keyword(s):  
Temporal Variability ◽  
Environmental Variables ◽  
Egg Production ◽  
Stock Assessment ◽  
Production Model ◽  
Estimation Methods ◽  
Statistical Framework ◽  
Spatio Temporal ◽  
The Relationship ◽  
Made In

Abstract Bernal, M., Stratoudakis, Y., Wood, S., Ibaibarriaga, L., Uriarte, A., Valdés, L., and Borchers, D. 2011. A revision of daily egg production estimation methods, with application to Atlanto-Iberian sardine. 2. Spatially and environmentally explicit estimates of egg production. – ICES Journal of Marine Science, 68: . A spatially and environmentally explicit egg production model is developed to accommodate a number of assumptions about the relationship between egg production and mortality and associated environmental variables. The general model was tested under different assumptions for Atlanto-Iberian sardine. It provides a flexible estimator of egg production, in which a range of assumptions and hypotheses can be tested in a structured manner within a well-defined statistical framework. Application of the model to Atlanto-Iberian sardine increased the precision of the egg production time-series, and allowed improvements to be made in understanding the spatio-temporal variability in egg production, as well as implications for ecology and stock assessment.

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