Heat flow in the presence of topography: Numerical analysis of data ensembles

Geophysics ◽  
1985 ◽  
Vol 50 (8) ◽  
pp. 1335-1341 ◽  
Author(s):  
Steven G. Henry ◽  
Henry N. Pollack
Keyword(s):  
Heat Flow ◽  
Surface Temperature ◽  
Three Dimensional ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Near Surface ◽  
Peruvian Andes ◽  
Variable Surface ◽  
The Individual ◽  
Variable Surface Temperature

We present a method of estimating subsurface temperatures and true regional heat flow in the presence of perturbing topography, variable surface temperature, and subsurface thermal conductivity contrasts. The method involves solution of the steady‐state three‐dimensional heat conduction equation by finite‐difference numerical techniques. The topography is represented by an irregular upper boundary and the variable surface temperature as a boundary condition along the irregular upper surface. Internal structural configurations and conductivity contrasts are easily accommodated. The principal variable input into the system is the deep basal (unperturbed) heat flow. The best value of heat flow is obtained by minimizing, in a least‐squares sense, the differences between observed and calculated temperatures. Temperature observations commonly are distributed irregularly in the near‐surface (perturbed) environment, in multiple vertical or inclined boreholes, tunnels, and/or mine galleries. The method is particularly suited to simultaneous analysis of an ensemble of distributed observations, in contrast to methods that focus on the perturbation to the temperature gradient in the vicinity of a single borehole. We used the method to reduce data obtained at fifteen newly established heat flow sites in the Bolivian and Peruvian Andes. We illustrate with three examples—a two‐dimensional model from the Bolivar Mine, Bolivia; (2) a three‐dimensional model using variable conductivity from the Cerro Verde Mine, Peru; and (3) a three‐dimensional model at the Colquiri Mine, Bolivia where temperature measurements were few and the distance between the individual boreholes was fairly large.

scholarly journals The Localization of Activity Sources in a Three-Dimensional Model of the Human Brain Using the Joint Analysis of EEG / sMRI Data

2019 ◽  
Vol 17 (3) ◽  
pp. 18-28
Author(s):  
E. Bykova ◽  
A. Savostyanov
Keyword(s):  
Inverse Problem ◽  
Brain Activity ◽  
Three Dimensional ◽  
Human Head ◽  
Joint Analysis ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Use Of Data ◽  
The Individual ◽  
The Brain

Despite the large number of existing methods of the diagnosis of the brain, brain remains the least studied part of the human body. Electroencephalography (EEG) is one of the most popular methods of studying of brain activity due to its relative cheapness, harmless, and mobility of equipment. While analyzing the EEG data of the brain, the problem of solving of the inverse problem of electroencephalography, the localization of the sources of electrical activity of the brain, arises. This problem can be formulated as follows: according to the signals recorded on the surface of the head, it is necessary to determine the location of sources of these signals in the brain. The purpose of my research is to develop a software system for localization of brain activity sources based on the joint analysis of EEG and sMRI data. There are various approaches to solving of the inverse problem of EEG. To obtain the most exact results, some of them involve the use of data on the individual anatomy of the human head – structural magnetic resonance imaging (sMRI data). In this paper, one of these approaches is supposed to be used – Electromagnetic Spatiotemporal Independent Component Analysis (EMSICA) proposed by A. Tsai. The article describes the main stages of the system, such as preprocessing of the initial data; the calculation of the special matrix of the EMSICA approach, the values of which show the level of activity of a certain part of the brain; visualization of brain activity sources on its three-dimensional model.

Simulating the Behaviour and Fate of an Oil Spill Using a Coupled Three-Dimensional Hydrodynamic Model

2014 ◽  
Vol 2014 (1) ◽  
pp. 901-918
Author(s):  
James A. Stronach ◽  
Aurelien Hospital
Keyword(s):  
Oil Spill ◽  
Hydrodynamic Model ◽  
Three Dimensional ◽  
Local Network ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Near Surface ◽  
Water Properties ◽  
Response Planning ◽  
The Impact

ABSTRACT Oil behavior and fate have been simulated extensively by several spill models. These simulations can be greatly enhanced by the use of a coupled three-dimensional model of currents and water properties to determine oil transport and weathering, both on the water surface and in the water column. Several physical and chemical processes such as vertical dispersion in response to wave action, resurfacing when waves die down, sinking through loss of volatiles and dissolution are essential in assessing the impact of an oil spill on the environment. Dissolution is especially important, considering the known toxicity of several of the constituents of liquid hydrocarbons. For this study, a three-dimensional hydrodynamic model of coastal British Columbia was coupled to an oil trajectory and weathering model in order to simulate the complete fate and behaviour of surface, shoreline-retained, dissolved, sunken and dispersed oil. Utilization of a three-dimensional model is the key to adequately modelling the transport of a spill in an estuarine region such as in the Strait of Georgia, B.C., where the distribution of currents and water properties is strongly affected by estuarine processes: the Fraser River enters at the surface and oceanic waters from the Pacific enter as a deep inflow. Three-dimensional currents and water properties were provided by the hydrodynamic model, H3D, a semi-implicit model using a staggered Arakawa grid and variable number of layers in the vertical direction to resolve near-surface processes. Waves were simulated using the wave model SWAN. Winds were obtained from the local network of coastal light stations and wind buoys. Stochastic modelling was conducted first, using only surface currents, to determine probabilistic maps of the oil trajectory on water and statistical results were extracted, such as the amount of shoreline oiled and the amount of oil evaporated, both for the ensemble of simulations constituting the stochastic simulation, as well as for any particular individual simulation. Deterministic scenarios were then selected and the fate of the oil, such as the dissolved and sunken fractions, was tracked over a 14 day period on the three-dimensional grid. This method has been used for environmental impact assessment and spill response planning.

scholarly journals Influence of Geometric Features Associativity of CAD Class Models on the Process of Their Updating – Comparative Analysis

2021 ◽  
Author(s):  
Grzegorz Świaczny
Keyword(s):  
3D Model ◽  
Three Dimensional ◽  
Optimal Solution ◽  
3D Models ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Initial Design ◽  
The Individual ◽  
Class Models ◽  
Positive Effect

This article deals with the topic of one of the most important features of modern CAx class systems – associativity. The term refers to the ability to form relations (links) between two or more objects (in terms of their selected features), and with the consequence creating an associative (linked) three-dimensional model. The author pays special attention to the very process of creating relations between objects, as it has a key impact on the structural stability of CAD class models, and thus on their susceptibility to possible modifications. To show that not all associativity brings a positive effect, the author presents two examples of its implementation. In order to emphasize the influence of the method of linking individual elements, both examples are based on the same 3D model – a thin-walled part with a positioning pin. That means the geometric form of the default part is the same, whereas only relations of the individual objects of the 3D model change. In the first scenario, correctly defined relations between objects make that the positioning pin offset does not affect the initial design conditions. The second scenario shows an incorrect implementation of associativity, as a result of which the same operation of positioning pin offset gives non-compliance with the initial design conditions and with the consequence an undesirable change in its geometry. The article is an attempt to draw attention to the fact that the associative structure of 3D models is not always equal to the optimal solution. Only the well-thought-out nature of associativity allows to use all its advantages.

Application of Knowledge Management in E-Commerce Based on Fuzzy Theory

2013 ◽  
Vol 475-476 ◽  
pp. 1207-1210
Author(s):  
Cheng Yu ◽  
Shi Wei Lin
Keyword(s):  
Knowledge Management ◽  
Fuzzy Theory ◽  
Three Dimensional ◽  
System Model ◽  
Sustainable Competitive Advantage ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Business System ◽  
The Individual ◽  
The Relationship

Basing on the introduction in the knowledge management and E-commerce concept and main theory, this paper discusses the relationship between knowledge management and E-commerce, put forward E-commerce to build the foundation o f knowledge, information flow and organization structure for knowledge management and the thesis that knowledge management constructs the sustainable competitive advantage for E-commerce. It also compares and analyzes the knowledge management and E-commerce popular model, Proposes the individual-centered organization, knowledge and business three dimensional model and the knowledge and business system model of business process which is based on the former.

scholarly journals APPLICATION OF LASER SCANNING FOR MONITORING THE CONDITION OF THE NEAR-SURFACE ARRAY ON THE OPEN PIT «KARACOMIR»

2019 ◽  
Vol 1 (1) ◽  
pp. 190-196 ◽  
Author(s):  
Danila Gorokhov ◽  
Nikita Dorosh ◽  
Elena Abueva
Keyword(s):  
Laser Scanning ◽  
Three Dimensional ◽  
The State ◽  
Open Pit ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Near Surface

This article discusses the use of laser scanning to monitor the state of the near-side array in the open pit «Karakomir». Obtaining a three-dimensional model and identifying linear deformations on it, the angle of inclination of the ledges in the area of landslides.

Wave scattering by multiple rows of circular ice floes

2009 ◽  
Vol 639 ◽  
pp. 213-238 ◽  
Author(s):  
L. G. BENNETTS ◽  
V. A. SQUIRE
Keyword(s):  
Finite Number ◽  
Wave Scattering ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Elastic Plates ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Linear Solution ◽  
Ice Floes ◽  
The Individual

A three-dimensional model of ocean-wave scattering in the marginal ice zone is constructed using linear theory under time-harmonic conditions. Individual floes are represented by circular elastic plates and are permitted to have a physically realistic draught. These floes are arranged into a finite number of parallel rows, and each row possesses an infinite number of identical floes that are evenly spaced. The floe properties may differ between rows, and the spacing between the rows is arbitrary.The vertical dependence of the solution is expanded in a finite number of modes, and through the use of a variational principle, a finite set of two-dimensional equations is generated from which the full-linear solution may be retrieved to any desired accuracy. By dictating the periodicity in each row to be identical, the scattering properties of the individual rows are combined using transfer matrices that take account of interactions between both propagating and evanescent waves.Numerical results are presented that investigate the differences between using the three-dimensional model and using a two-dimensional model in which the rows are replaced with strips of ice. Furthermore, Bragg resonance is identified when the rows are identical and equi-spaced, and its reduction when the inhomogeneities, that are accommodated by the model, are introduced is shown.

scholarly journals WAVE TRANSMISSION ACROSS SUBMERGED NEAR-SURFACE BREAKWATERS

1986 ◽  
Vol 1 (20) ◽  
pp. 126 ◽  
Author(s):  
Clark B. Adams ◽  
Choule J. Sonu
Keyword(s):  
Model Test ◽  
Three Dimensional ◽  
Wave Transmission ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Submerged Breakwater ◽  
Near Surface ◽  
Santa Monica

Wave transmission across a submerged breakwater at Santa Monica, California, is examined through a three-dimensional model test. The results agree with empirical criteria previously proposed by Tanaka (1976).

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