scholarly journals High Resolution Numerical Model for Salinity Transport in Rivers During a Tsunami Attack

2018 ◽  
Vol 13 (4) ◽  
pp. 767-779
Author(s):  
Hiroshi Nagashima ◽  
Nozomu Yoneyama ◽  
◽  
Keyword(s):  
Spatial Distribution ◽  
Temporal Change ◽  
Saline Water ◽  
Three Dimensional ◽  
Specific Area ◽  
Two Dimensional ◽  
Tsunami Propagation ◽  
Salinity Transport ◽  
Propagation Analysis ◽  
Potential Damage

In the event of a tsunami, saltwater flows into rivers and water purification plants must stop taking water from rivers to prevent entry of saline water into the plant owing to potential damage to machinery and contamination of the system. This leads to interruption of water supply during disaster. In this study, a salinity transport simulation model that can carry out a three-dimensional salinity behavior analysis in a specific area and a horizontal two-dimensional tsunami propagation analysis simultaneously was developed to predict saltwater behavior in rivers during a tsunami. These models are structured so that the influence of the boundary of the 3D domain can be excluded without significantly increasing the calculation load. The model was used to simulate saltwater behavior in the Yodo River in Japan during a tsunami. The spatial distribution and temporal change of saltwater under various river flows were quantitatively predicted, and the effectiveness of possible countermeasures in diminishing the duration of water-intake shutdown and the presence of brackish water in upstream areas was assessed.

High Resolution Synchrotron X-Ray Diffraction Tomography Of Large-Grained Samples

1996 ◽  
Vol 437 ◽  
Author(s):  
D.P. Piotrowski ◽  
S.R. Stock ◽  
A. Guvenilir ◽  
J.D. Haase ◽  
Z.U. Rek
Keyword(s):  
Spatial Distribution ◽  
High Resolution ◽  
Three Dimensional ◽  
Polycrystalline Materials ◽  
Diffraction Tomography ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
Image Storage ◽  
X Ray ◽  
Dimensional Distribution

AbstractIn order to understand the macroscopic response of polycrystalline structural materials to loading, it is frequently essential to know the spatial distribution of strain as well as the variation of micro-texture on the scale of 100 μm. The methods must be nondestructive, however, if the three-dimensional evolution of strain is to be studied. This paper describes an approach to high resolution synchrotron x-ray diffraction tomography of polycrystalline materials. Results from model samples of randomly-packed, millimeter-sized pieces of Si wafers and of similarly sized single-crystal Al blocks have been obtained which indicate that polychromatic beams collimated to 30 μm diameter can be used to determine the depth of diffracting volume elements within ± 70 μm. The variation in the two-dimensional distribution of diffracted intensity with changing sample to detector separation is recorded on image storage plates and used to infer the depth of diffracting volume elements.

scholarly journals Geostatistical FDEM inversion: a three-dimensional real case application

2021 ◽  
Author(s):  
Leonardo Azevedo ◽  
João Narciso ◽  
Ellen Van De Vijver
Keyword(s):  
Spatial Distribution ◽  
Physical Properties ◽  
Three Dimensional ◽  
Real Case ◽  
Small Scale ◽  
Inversion Method ◽  
Two Dimensional ◽  
Data Set ◽  
Near Surface ◽  
Direct Observations

<p>The near surface is a complex and often highly heterogeneous system as its current status results from interacting processes of both natural and anthropogenic origin. Effective sustainable management and land use planning, especially in urban environments, demands high-resolution subsurface property models enabling to capture small-scale processes of interest. The modelling methods based only on discrete direct observations from conventional invasive sampling techniques have limitations with respect to capturing the spatial variability of these systems. Near-surface geophysical surveys are emerging as powerful techniques to provide indirect measurements of subsurface properties. Their integration with direct observations has the potential for better predicting the spatial distribution of the subsurface physical properties of interest and capture the heterogeneities of the near-surface systems.</p><p>Within the most common geophysical techniques, frequency-domain electromagnetic (FDEM) induction methods have demonstrated their potential and efficiency to characterize heterogeneous deposits due to their simultaneous sensitivity to electrical conductivity (EC) and magnetic susceptibility (MS). The inverse modelling of FDEM data based on geostatistical techniques allows to go beyond conventional analyses of FDEM data. This geostatistical FDEM inversion method uses stochastic sequential simulation and co-simulation to perturbate the model parameter space and the corresponding FDEM forward model solutions, including both the synthetic FDEM responses and their sensitivity to changes on the physical properties of interest. A stochastic optimization driven by the misfit between true and synthetic FDEM data is applied to iterative towards a final subsurface model. This method not only improve the confidence of the obtained EC and MS inverted models but also allows to quantify the uncertainty related to them. Furthermore, taking into account spatial correlations enables more accurate prediction of the spatial distribution of subsurface properties and a more realistic reconstruction of small-scale spatial variations, even when considering highly heterogeneous near surface systems. Moreover, a main advantage of this iterative geostatistical FDEM inversion method is its ability to flexibly integrate data with different resolution in the same framework.</p><p>In this work, we apply this iterative geostatistical FDEM inversion technique, which has already been successfully demonstrated for one- and two-dimensional applications, to invert a real case FDEM data set in three dimensions. The FDEM survey data set was collected on a site located near Knowlton (Dorset, UK), which is geologically characterized by Cretaceous chalk overlain by Quaternary siliciclastic sand deposits. The subsurface at the site is known to contain several archaeological features, which produces strong local in-phase anomalies in the FDEM survey data. We discuss the particular challenges involved in the three-dimensional application of the inversion method to a real case data set and compare our results against previously obtained ones for one- and two-dimensional approximations.</p>

scholarly journals THREE-DIMENSIONAL DETECTION OF GAMMA RADIATION AND POLLUTING GASES USING QUADROCOPTERS

2020 ◽  
Vol 47 (1) ◽  
pp. 102-116
Author(s):  
A. Molnar
Keyword(s):  
Spatial Distribution ◽  
Gamma Radiation ◽  
Gamma Ray ◽  
Three Dimensional ◽  
Remote Sensing Data ◽  
Specific Area ◽  
Measured Data ◽  
Mobile Platforms ◽  
Industrial Facilities ◽  
Spatial Coordinates

Abstract. Aim. Accurate knowledge of the extent and local distribution of pollution plays a key role in many areas of life.Method. Although there are many well-known and generally-accepted methods for obtaining the intended data, these methods do not give a satisfactory result in cases when it is necessary to determine the exact parameters of pollution quickly and in a relatively small area (e.g. an industrial zone of several square kilometers, a residential area, etc.) and to determine changes in these parameters as expressed numerically. Small UAVs (multicopter with fixed or rotating wing) were equipped with sensitive detectors for gamma rays and polluting gases, including the assignation of flight data coordinates to the measured data. Such informational groupings provide the opportunity to determine the distribution of radiation or air polluting gases. Using this method, it is possible to identify and localise illegally-stored or illegally-released gamma ray emitting materials, continuously monitor pollution caused by chemical disasters and determine the spatial distribution of pollution.Results. The article presents systems based on practical experiments, which, in the case of using a gamma detector, allow the localisation of objects using low radiation doses along with a high-quality map of gamma radiation in a specific area; and, in the case of gas sensors, the visualisation of the spatial distribution of a polluting gas. The method is used primarily in the field to detect gamma emitters with low activity or to analyse the emission of industrial facilities with the emission of pollutants.Conclusion. The combination of spatial coordinates with remote sensing data comprises an effective meas-urement method. The developed system is generally applicable for mobile platforms equipped with sensors. The systems are designed to provide fast, efficient and reliable measurements that can be used for both detection and control. The type of pollutants to be measured depends on the sensors used. The experiments also indicate that, when replacing the used sensors, it may be necessary to change the processing of the measured data in accordance with the characteristics of the particular sensor; however, in general, data processing and visualisation of the results can be carried out in practice.

Chemical Structure-Based Three-Dimensional Reconstruction of Human Cortical Bone from Two-Dimensional Infrared Images

2002 ◽  
Vol 56 (4) ◽  
pp. 419-422 ◽  
Author(s):  
Hou Ou-Yang ◽  
Eleftherios P. Paschalis ◽  
Adele L. Boskey ◽  
Richard Mendelsohn
Keyword(s):  
Spatial Distribution ◽  
Cortical Bone ◽  
Chemical Structure ◽  
Matrix Protein ◽  
Structural Parameters ◽  
Three Dimensional ◽  
Sample Length ◽  
Two Dimensional ◽  
Infrared Images ◽  
Collagen Crosslinks

A method is described for the construction of three-dimensional infrared images from serial two-dimensional infrared images of various chemical structure parameters acquired from cortical bone. A series of serial cortical bone sections, each 4–5 μm thick, separated by ∼100 μm, were microtomed from PMMA-embedded normal human tibia. Twenty-three IR image cubes were acquired from this series, corresponding to an overall sample length of ∼2.2 mm. From each image cube, IR images of the spatial distribution of the mineral-to-matrix (protein) ratio, the mineral crystallinity, and the ratio of nonreducible-to-reducible collagen crosslinks were calculated. Two-dimensional images were stacked to form a 3D view of the cortical bone, with contrast provided by variation in the spatial distribution of any of the aforementioned chemical/molecular structural parameters.

scholarly journals Experimental and Numerical Studies in a Centrifugal Pump With Two-Dimensional Curved Blades in Cavitating Condition

2003 ◽  
Vol 125 (6) ◽  
pp. 970-978 ◽  
Author(s):  
O. Coutier-Delgosha ◽  
R. Fortes-Patella ◽  
J. L. Reboud ◽  
M. Hofmann ◽  
B. Stoffel
Keyword(s):  
Spatial Distribution ◽  
Numerical Model ◽  
Three Dimensional ◽  
Rotating Machinery ◽  
Two Dimensional ◽  
Special Test ◽  
Cavitating Flows ◽  
Flow Conditions ◽  
Numerical Studies ◽  
And Performance

In the presented study a special test pump with two-dimensional curvature blade geometry was investigated in cavitating and noncavitating conditions using different experimental techniques and a three-dimensional numerical model implemented to study cavitating flows. Experimental and numerical results concerning pump characteristics and performance breakdown were compared at different flow conditions. Appearing types of cavitation and the spatial distribution of vapor structures within the impeller were also analyzed. These results show the ability of the model to simulate the complex three-dimensional development of cavitation in a rotating machinery, and the associated effects on the performance.

High Resolution Microscopy of Multi-Layered Biological Crystals

1982 ◽  
Vol 40 ◽  
pp. 80-83
Author(s):  
H.A. Cohen ◽  
T.W. Jeng ◽  
W. Chiu
Keyword(s):  
High Resolution ◽  
Low Dose ◽  
Three Dimensional ◽  
Data Interpretation ◽  
Two Dimensional ◽  
Biological Objects ◽  
Density Maps ◽  
Density Map ◽  
Complex Crystal ◽  
High Resolution Microscopy

This tutorial will discuss the methodology of low dose electron diffraction and imaging of crystalline biological objects, the problems of data interpretation for two-dimensional projected density maps of glucose embedded protein crystals, the factors to be considered in combining tilt data from three-dimensional crystals, and finally, the prospects of achieving a high resolution three-dimensional density map of a biological crystal. This methodology will be illustrated using two proteins under investigation in our laboratory, the T4 DNA helix destabilizing protein gp32*I and the crotoxin complex crystal.

Instrumentation For Quantitative Microscopy

1977 ◽  
Vol 35 ◽  
pp. 206-209
Author(s):  
B. Ralph ◽  
A.R. Jones
Keyword(s):  
Volume Fraction ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Automatic Data ◽  
Phase Volume Fraction ◽  
Statistical Confidence ◽  
Resultant Data ◽  
Automatic Data Collection ◽  
Third Dimension ◽  
Evolution Of Microstructure

In all fields of microscopy there is an increasing interest in the quantification of microstructure. This interest may stem from a desire to establish quality control parameters or may have a more fundamental requirement involving the derivation of parameters which partially or completely define the three dimensional nature of the microstructure. This latter categorey of study may arise from an interest in the evolution of microstructure or from a desire to generate detailed property/microstructure relationships. In the more fundamental studies some convolution of two-dimensional data into the third dimension (stereological analysis) will be necessary.In some cases the two-dimensional data may be acquired relatively easily without recourse to automatic data collection and further, it may prove possible to perform the data reduction and analysis relatively easily. In such cases the only recourse to machines may well be in establishing the statistical confidence of the resultant data. Such relatively straightforward studies tend to result from acquiring data on the whole assemblage of features making up the microstructure. In this field data mode, when parameters such as phase volume fraction, mean size etc. are sought, the main case for resorting to automation is in order to perform repetitive analyses since each analysis is relatively easily performed.

A linearity test for thick specimens imaged by HVEM over a 180° angular range

1991 ◽  
Vol 49 ◽  
pp. 552-553
Author(s):  
Yu Liu
Keyword(s):  
Phase Contrast ◽  
Three Dimensional ◽  
Angular Range ◽  
Two Dimensional ◽  
Back Projection ◽  
Line Integral ◽  
Exponential Law ◽  
Transmission Electron ◽  
Absorption Law ◽  
Linearity Test

The image obtained in a transmission electron microscope is the two-dimensional projection of a three-dimensional (3D) object. The 3D reconstruction of the object can be calculated from a series of projections by back-projection, but this algorithm assumes that the image is linearly related to a line integral of the object function. However, there are two kinds of contrast in electron microscopy, scattering and phase contrast, of which only the latter is linear with the optical density (OD) in the micrograph. Therefore the OD can be used as a measure of the projection only for thin specimens where phase contrast dominates the image. For thick specimens, where scattering contrast predominates, an exponential absorption law holds, and a logarithm of OD must be used. However, for large thicknesses, the simple exponential law might break down due to multiple and inelastic scattering.

An Image Reconstruction System Applied to High Voltage Microscopy

1975 ◽  
Vol 33 ◽  
pp. 292-293
Author(s):  
D. E. Johnson
Keyword(s):  
High Voltage ◽  
Prior Information ◽  
Block Diagram ◽  
Three Dimensional ◽  
Real Space ◽  
Two Dimensional ◽  
Efficient Manner ◽  
Fourier Methods ◽  
Tilt Series ◽  
Methods Of Reconstruction

Increased specimen penetration; the principle advantage of high voltage microscopy, is accompanied by an increased need to utilize information on three dimensional specimen structure available in the form of two dimensional projections (i.e. micrographs). We are engaged in a program to develop methods which allow the maximum use of information contained in a through tilt series of micrographs to determine three dimensional speciman structure.In general, we are dealing with structures lacking in symmetry and with projections available from only a limited span of angles (±60°). For these reasons, we must make maximum use of any prior information available about the specimen. To do this in the most efficient manner, we have concentrated on iterative, real space methods rather than Fourier methods of reconstruction. The particular iterative algorithm we have developed is given in detail in ref. 3. A block diagram of the complete reconstruction system is shown in fig. 1.

Sign in / Sign up

Export Citation Format

Share Document