Early stages of infiltration in two- and three-dimensional systems

Soil Research ◽  
1969 ◽  
Vol 7 (3) ◽  
pp. 213 ◽  
Author(s):  
JR Philip
Keyword(s):  
Three Dimensional ◽  
Delta Function ◽  
The Third ◽  
Spherical Cavities ◽  
Leading Term ◽  
Flow Components ◽  
Function Approximations ◽  
Short Time ◽  
Practical Implications ◽  
Linear Integrodifferential Equation

The paper establishes the series solution of problems of infiltration from cylindrical and spherical cavities. The leading term is the fundamental horizontal absorption solution. The second term, representing linearly additive interactions of gravity and m-dimensionality (m = 2, 3), follows at once from known solutions for one-dimensional infiltration and for m-dimensional absorption. The third term is evaluated by solution of an ordinary linear integrodifferential equation. Higher terms involve circumferential flow components, and partial equations must be solved to evaluate them. For small enough times these higher terms are negligible. Physically, this implies that flow is essentially radial at such times; mathematically, that, taken no further than the third term, the solution applies indifferently to infiltration from cavities and from semicircular furrows (m = 2) and hemispherical basins (m = 3). The relation between this solution and the linearized and delta-function approximations is explored. The practical implications for sorptivity determinations based on short-time infiltration from furrows and basins are examined.

The orbit of Pluto over a long interval of time

1966 ◽  
Vol 25 ◽  
pp. 227-229 ◽  
Author(s):  
D. Brouwer
Keyword(s):  
Periodic Orbit ◽  
Numerical Integration ◽  
Restricted Problem ◽  
Three Dimensional ◽  
The Third ◽  
Circular Restricted Problem ◽  
Resonance Relation

The paper presents a summary of the results obtained by C. J. Cohen and E. C. Hubbard, who established by numerical integration that a resonance relation exists between the orbits of Neptune and Pluto. The problem may be explored further by approximating the motion of Pluto by that of a particle with negligible mass in the three-dimensional (circular) restricted problem. The mass of Pluto and the eccentricity of Neptune's orbit are ignored in this approximation. Significant features of the problem appear to be the presence of two critical arguments and the possibility that the orbit may be related to a periodic orbit of the third kind.

scholarly journals A computational framework for modeling cell–matrix interactions in soft biological tissues

2021 ◽  
Author(s):  
Jonas F. Eichinger ◽  
Maximilian J. Grill ◽  
Iman Davoodi Kermani ◽  
Roland C. Aydin ◽  
Wolfgang A. Wall ◽  
...  
Keyword(s):  
Soft Tissues ◽  
Three Dimensional ◽  
Biological Tissues ◽  
Computational Framework ◽  
Cell Matrix ◽  
Physiological Processes ◽  
Matrix Interactions ◽  
Mechanical Homeostasis ◽  
Cell Matrix Interactions ◽  
Short Time

AbstractLiving soft tissues appear to promote the development and maintenance of a preferred mechanical state within a defined tolerance around a so-called set point. This phenomenon is often referred to as mechanical homeostasis. In contradiction to the prominent role of mechanical homeostasis in various (patho)physiological processes, its underlying micromechanical mechanisms acting on the level of individual cells and fibers remain poorly understood, especially how these mechanisms on the microscale lead to what we macroscopically call mechanical homeostasis. Here, we present a novel computational framework based on the finite element method that is constructed bottom up, that is, it models key mechanobiological mechanisms such as actin cytoskeleton contraction and molecular clutch behavior of individual cells interacting with a reconstructed three-dimensional extracellular fiber matrix. The framework reproduces many experimental observations regarding mechanical homeostasis on short time scales (hours), in which the deposition and degradation of extracellular matrix can largely be neglected. This model can serve as a systematic tool for future in silico studies of the origin of the numerous still unexplained experimental observations about mechanical homeostasis.

scholarly journals Modeling of dense well block point bar architecture based on geological vector information: A case study of the third member of Quantou Formation in Songliao Basin

2021 ◽  
Vol 13 (1) ◽  
pp. 39-48
Author(s):  
Chao Luo ◽  
Ailin Jia ◽  
Jianlin Guo ◽  
Wei Liu ◽  
Nanxin Yin ◽  
...  
Keyword(s):  
River Sediments ◽  
Three Dimensional ◽  
Songliao Basin ◽  
Point Bar ◽  
Meandering River ◽  
Architecture Model ◽  
The Third ◽  
Continuous Convergence ◽  
Vector Information ◽  
Architecture Modeling

Abstract Although stochastic modeling methods can achieve multiple implementations of sedimentary microfacies model in dense well blocks, it is difficult to realize continuous convergence of well spacing. Taking the small high-sinuosity meandering river sediments of the third member of Quantou Formation in Songliao Basin as an example, a deterministic modeling method based on geological vector information was explored in this article. Quantitative geological characteristics of point bar sediments were analyzed by field outcrops, modern sediments, and dense well block anatomy. The lateral extension distance, length, and spacing parameters of the point bar were used to quantitatively characterize the thickness, dip angle, and frequency of the lateral layer. In addition, the three-dimensional architecture modeling of the point bar was carried out in the study. The established three-dimensional architecture model of well X24-1 had continuous convergence near all wells, which conformed to the geological knowledge of small high-sinuosity meandering river, and verified the reliability of this method in the process of geological modeling in dense well blocks.

Comparison of the reluctance laminated and solid rotor synchronous machine operating at high temperatures

2019 ◽  
Vol 38 (4) ◽  
pp. 1111-1119 ◽  
Author(s):  
Marcin Lefik ◽  
Krzysztof Komeza ◽  
Ewa Napieralska-Juszczak ◽  
Daniel Roger ◽  
Piotr Andrzej Napieralski
Keyword(s):  
High Speed ◽  
Design Methodology ◽  
Three Dimensional ◽  
Synchronous Machine ◽  
Point Of View ◽  
Heat Sources ◽  
Model Calculations ◽  
Content Type ◽  
Thermal Phenomenon ◽  
Practical Implications

Purpose The purpose of this paper is to present a comparison between reluctance synchronous machine-enabling work at high internal temperature (HT° machine) with laminated and solid rotor. Design/methodology/approach To obtain heat sources for the thermal model, calculations of the electromagnetic field were made using the Opera 3D program including effect of rotation and the resulting eddy current losses. To analyse the thermal phenomenon, the 3D coupled thermal-fluid (CFD) model is used. Findings The presented results show clearly that laminated construction is much better from a point of view of efficiency and temperature. However, solid construction can be interesting for high speed machines due to their mechanical robustness. Research limitations/implications The main problem, despite the use of parallel calculations, is the long calculation time. Practical implications The obtained simulation and experimental results show the possibility of building a machine operating at a much higher ambient temperature than it was previously produced for example in the vicinity of the aircraft turbines. Originality/value The paper presents the application of fully three-dimensional coupled electromagnetic and thermal analysis of new machine constructions designed for elevated temperature.

scholarly journals Reconciling Lagrangian Diffusivity and Effective Diffusivity in Contour-Based Coordinates

2019 ◽  
Vol 49 (6) ◽  
pp. 1521-1539
Author(s):  
Yu-Kun Qian ◽  
Shiqiu Peng ◽  
Chang-Xia Liang
Keyword(s):  
Time Lag ◽  
Effective Diffusivity ◽  
Delta Function ◽  
Spreading Rate ◽  
Particle Dispersion ◽  
Small Scale ◽  
Time Lags ◽  
Conservative Tracer ◽  
Stirring Effect ◽  
Short Time

AbstractThe present study reconciles theoretical differences between the Lagrangian diffusivity and effective diffusivity in a transformed spatial coordinate based on the contours of a quasi-conservative tracer. In the transformed coordinate, any adiabatic stirring effect, such as shear-induced dispersion, is naturally isolated from diabatic cross-contour motions. Therefore, Lagrangian particle motions in the transformed coordinate obey a transformed zeroth-order stochastic (i.e., random walk) model with the diffusivity replaced by the effective diffusivity. Such a stochastic model becomes the theoretical foundation on which both diffusivities are exactly unified. In the absence of small-scale diffusion, particles do not disperse at all in the transformed contour coordinate. Besides, the corresponding Lagrangian autocorrelation becomes a delta function and is thus free from pronounced overshoot and negative lobe at short time lags that may be induced by either Rossby waves or mesoscale eddies; that is, particles decorrelate immediately and Lagrangian diffusivity is already asymptotic no matter how small the time lag is. The resulting instantaneous Lagrangian spreading rate is thus conceptually identical to the effective diffusivity that only measures the instantaneous irreversible mixing. In these regards, the present study provides a new look at particle dispersion in contour-based coordinates.

The generation of adaptive assembly from predicting change propagation

2015 ◽  
Vol 35 (3) ◽  
pp. 269-280 ◽  
Author(s):  
Hu Qiao ◽  
Rong Mo ◽  
Ying Xiang
Keyword(s):  
Computer Aided Design ◽  
Three Dimensional ◽  
Original Method ◽  
Change Propagation ◽  
Assembly Model ◽  
Practical Application ◽  
Content Type ◽  
Design Structure ◽  
Aided Design ◽  
Practical Implications

Purpose – The purpose of this paper is to establish an adaptive assembly, to realize the adaptive changing of the models and to improve the flexibility and reliability of assembly change. For a three-dimensional (3D) computer-aided design (CAD) assembly in a changing process, there are two practical problems. One is delivering parameters’ information not smoothly. The other one is to easily destroy an assembly structure. Design/methodology/approach – The paper establishes associated parameters design structure matrix of related parts, and predicts possible propagation paths of the parameters. Based on the predicted path, structured storage is made for the affected parameters, tolerance range and the calculation relations. The study combines structured path information and all constrained assemblies to build the adaptive assembly, proposes an adaptive change algorithm for assembly changing and discusses the extendibility of the adaptive assembly. Findings – The approach would improve the flexibility and reliability of assembly change and be applied to different CAD platform. Practical implications – The examples illustrate the construction and adaptive behavior of the assembly and verify the feasibility and reasonability of the adaptive assembly in practical application. Originality/value – The adaptive assembly model proposed in the paper is an original method to assembly change. And compared with other methods, good results have been obtained.

“The Greatest Thrill I Get is When I Hear a Criminal Say, ‘Yes, I Did it’”: Race and the Third Degree in New Orleans, 1920–1945

2016 ◽  
Vol 34 (1) ◽  
pp. 1-44
Author(s):  
Jeffrey S. Adler
Keyword(s):  
African American ◽  
Medical Care ◽  
New Orleans ◽  
Police Officer ◽  
Police Officers ◽  
Constitutional Protection ◽  
The Third ◽  
The Face ◽  
A Cell ◽  
Short Time

On May 11, 1938, two New Orleans policemen entered the Astoria Restaurant, marched to the kitchen, and approached Loyd D. T. Washington, a 41-year-old African American cook. They informed Washington that they would be taking him to the First Precinct station for questioning, although they assured the cook that he need not change his clothes and “should be right back” to the “Negro restaurant,” where he had worked for 3 years. Immediately after arriving at the station house, police officers “surrounded” Washington, showed him a photograph of a man, and announced that he had killed a white man in Yazoo City, Mississippi, 20 years earlier. When Washington insisted that he did not know the man in the photograph, that he had never been to (or even heard of) Yazoo City, and that he had been in the army at the time of the murder, the law enforcers confined him in a cell, although they had no warrant for his arrest and did not charge him with any crime. The following day, a detective brought him to the “show-up room” in the precinct house, where he continued the interrogation and, according to Washington, “tried to make me sign papers stating that I had killed a white man” in Mississippi. As every African American New Orleanian knew, the show-up (or line-up) room was the setting where detectives tortured suspects and extracted confessions. “You know you killed him, Nigger,” the detective roared. Washington, however, refused to confess, and the detective began punching him in the face, knocking out five of his teeth. After Washington crumbled to the floor, the detective repeatedly kicked him and broke one of his ribs. The beating continued for an hour, until other policemen restrained the detective, saying “give him a chance to confess and if he doesn't you may start again.” But Washington did not confess, and the violent interrogation began anew. A short time later, another police officer interrupted the detective, telling him “do not kill this man in here, after all he is wanted in Yazoo City.” Bloodied and writhing in pain, Washington asked to contact his family, but the request was ignored. Because he had not been formally charged with a crime, New Orleans law enforcers believed that Washington had no constitutional protection again self-incrimination or coercive interrogation and no right to an arraignment or bail, and they had no obligation to contact his relatives or to provide medical care for him.

An English Library at Trinidad, 1633

1955 ◽  
Vol 12 (1) ◽  
pp. 25-41
Author(s):  
Eleanor B. Adams
Keyword(s):  
Sixteenth Century ◽  
West Indian ◽  
The West ◽  
The Third ◽  
Caribbean Area ◽  
The Caribbean ◽  
El Dorado ◽  
Short Time

The island of Trinidad was discovered by Columbus on the third voyage in 1498. One of the largest and most fertile of the West Indian islands, for many years it remained on the fringe of European activity in the Caribbean area and on the coasts of Venezuela and Guiana. A Spanish settlement was founded there in 1532, but apparently it disintegrated within a short time. Toward the end of the sixteenth century Berrio and Raleigh fought for possession of the island, but chiefly as a convenient base for their rival search for El Dorado, or Manoa, the Golden Man and the mythical city of gold. Throughout the sixteenth and early seventeenth centuries explorers, corsairs, and contraband traders, Spanish, French, English, and Dutch, passed near its shores, and many of them may well have paused there to refresh themselves and to make necessary repairs to their vessels. But the records are scanty and we know little of such events or of the settlements that existed from time to time.

Theory of Electron Diffraction by Crystals

1967 ◽  
Vol 22 (4) ◽  
pp. 422-431 ◽  
Author(s):  
Kyozaburo Kambe
Keyword(s):  
Integral Equation ◽  
Electron Diffraction ◽  
General Theory ◽  
Green’S Function ◽  
Green's Function ◽  
Scattering Problem ◽  
Three Dimensional ◽  
Two Dimensions ◽  
The Third ◽  
Third Dimension

A general theory of electron diffraction by crystals is developed. The crystals are assumed to be infinitely extended in two dimensions and finite in the third dimension. For the scattering problem by this structure two-dimensionally expanded forms of GREEN’S function and integral equation are at first derived, and combined in single three-dimensional forms. EWALD’S method is applied to sum up the series for GREEN’S function.

Imaging Cracks in Bones Using Acoustic Nonlinearity: A Simulation Study

2011 ◽  
Vol 97 (5) ◽  
pp. 728-733
Author(s):  
Yang Liu ◽  
Xiasheng Guo ◽  
Zhao Da ◽  
Dong Zhang ◽  
Xiufen Gong
Keyword(s):  
Time Reversal ◽  
Three Dimensional ◽  
Harmonic Component ◽  
Ultrasonic Signal ◽  
Long Bone ◽  
Third Harmonic ◽  
Acoustic Nonlinearity ◽  
The Third ◽  
Nonlinear Approach ◽  
Radial Depth

This article proposes an acoustic nonlinear approach combined with the time reversal technique to image cracks in long bones. In this method, the scattered ultrasound generated from the crack is recorded, and the third harmonic nonlinear component of the ultrasonic signal is used to reconstruct an image of the crack by the time reversal process. Numerical simulations are performed to examine the validity of this approach. The fatigue long bone is modeled as a hollow cylinder with a crack of 1, 0.1, and 0.225 mm in axial, radial and circumferential directions respectively. A broadband 500 kHz ultrasonic signal is used as the exciting signal, and the extended three-dimensional Preisach-Mayergoyz model is used to describe the nonclassical nonlinear dynamics of the crack. Time reversal is carried out by using the filtered third harmonic component. The localization capability depends on the radial depth of the crack.

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