scholarly journals Computational Simulations of Flow and Oxygen/Drug Delivery in a Three-Dimensional Capillary Network

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
T.-W. Lee ◽  
K.-S. Bae ◽  
Heung S. Choi ◽  
Ming-Jyh Chern
Keyword(s):  
Transport Model ◽  
Three Dimensional ◽  
Current Method ◽  
Current Approach ◽  
Capillary Network ◽  
Newtonian Viscosity ◽  
Other Substances ◽  
Three Dimensional Models ◽  
The One ◽  
Unsteady Effects

A computational fluid dynamics (CFD) model is developed to simulate the flow and delivery of oxygen and other substances in a capillary network. A three-dimensional capillary network has been constructed to replicate the one studied by Secomb et al. (2000), and the computational framework features a non-Newtonian viscosity model of blood and the oxygen transport model including in-stream oxygen-hemoglobin dissociation and wall flux due to tissue absorption, as well as an ability to study delivery of drugs and other materials in the capillary streams. The model is first run to compute the volumetric flow rates from the velocity profiles in the segments and compared with Secomb’s work with good agreement. Effects of abnormal pressure and stenosis conditions, as well as those arising from different capillary configurations, on the flow and oxygen delivery are investigated, along with a brief look at the unsteady effects and drug dispersion in the capillary network. The current approach allows for inclusion of oxygen and other material transports, including drugs, nutrients, or contaminants based on the flow simulations. Also, three-dimensional models of complex circulatory systems ranging in scale from macro- to microvascular vessels, in principle, can be constructed and analyzed in detail using the current method.

scholarly journals Alternative Divulgation of the Local Sculptural Heritage: Construction of Paper Toys and Use of the Minecraft Video Game

2018 ◽  
Vol 10 (11) ◽  
pp. 4262 ◽  
Author(s):  
Cecile Meier ◽  
Jose Saorín ◽  
Jorge de la Torre-Cantero ◽  
Manuel Díaz-Alemán
Keyword(s):  
Video Game ◽  
User Satisfaction ◽  
Three Dimensional ◽  
3D Models ◽  
Alternative Methods ◽  
Pilot Studies ◽  
Cultural Patrimony ◽  
3D Printed ◽  
Three Dimensional Models ◽  
The One

At present it is easy to digitalize sculptural heritage in 3D. Three-dimensional models allow for visualization of the work from all angles. The result can be seen in three-dimensional visors, in virtual reality, or by means of 3D-printed replicas. However, the recipient continues to be, as is also the case in books and videos, a passive spectator of the cultural patrimony. In order to promote participation and to increase interest in local heritage, alternative methods for promotion of the digital patrimony have been developed. In this article, two means of publicizing local (less-known) heritage in an active manner have been described. On the one hand, the transformation of 3D models into cut-outs (paper toys) where it is necessary to make the sculptures by hand, and on the other hand, the incorporation of the models into the video game Minecraft, an immersed 3D world which permits visiting or generating content. To validate these alternatives, two examples based on the sculptures of Santa Cruz de Tenerife (Spain) have been created, and they have been used in pilot studies in schools in order to obtain a first appraisal of user satisfaction.

A Model for Potential Deterministic Effects in Transonic Compressor Flows

2009 ◽  
Author(s):  
Stefan Stollenwerk ◽  
Dirk Nu¨rnberger
Keyword(s):  
Transport Model ◽  
Three Dimensional ◽  
Flat Plates ◽  
Additional Source ◽  
Shock Interactions ◽  
Transonic Compressor ◽  
Unsteady Interaction ◽  
Stator Blade ◽  
Unsteady Effects ◽  
The Impact

The unsteady interaction between blade rows is very important in highly loaded compressors because of its influence on operating performance. One important effect in this context is the impact of a rotor bow shock on the wake of an upstream stator blade. A new transport model is proposed which introduces such deterministic unsteady effects in a steady solution environment. Deterministic stresses are added to the stationary RANS equations by means of an additional source term. The presented approach combines the advantages of time-accurate and stationary simulation procedures, i.e. physical accuracy and computational efficiency. A generic cascade of flat plates and a transonic stator-rotor configuration are investigated numerically using time-accurate methods in order to analyze the wake-shock interactions. The results are compared with steady mixing-plane solutions to point out their shortcomings regarding unsteady effects and to illustrate the demands of a deterministic stress approach. The model is then calibrated for the generic cascade before it is applied to the real three-dimensional compressor stage.

scholarly journals On the Merits of Using a 3D-FGAT Assimilation Scheme with an Outer Loop for Atmospheric Situations Governed by Transport

2010 ◽  
Vol 138 (12) ◽  
pp. 4509-4522 ◽  
Author(s):  
Sébastien Massart ◽  
Benjamin Pajot ◽  
Andrea Piacentini ◽  
Olivier Pannekoucke
Keyword(s):  
Transport Model ◽  
Computing Time ◽  
Three Dimensional ◽  
Observation Time ◽  
Chemical Transport Model ◽  
Outer Loop ◽  
Pros And Cons ◽  
The One ◽  
The Right ◽  
Assimilation Scheme

Abstract Three-dimensional variational data assimilation (3D-Var) with the first guess at appropriate time (FGAT) appears to be an attractive compromise between accuracy and overall computing time. It is computationally cheaper than four-dimensional (4D)-Var as the increment is not propagated back and forth in time by a model, yet the comparison between the model and the observations is still computed at the right observation time. An interesting feature of the 4D-Var is the iterative process known as the outer loop. This outer-loop approach can also be used in conjunction with 3D-FGAT. But it requires the application of the 3D-FGAT analysis increment at the beginning of the assimilation window. The pros and cons of using this unusual 3D-FGAT variant are illustrated in this paper on two applications focused on the transport, one of the main phenomena governing the atmospheric evolution. The first one is the one-dimensional advection of a passive tracer. By three representative situations, it shows the benefits of the outer loop, except for practical situations driven by very rapid dynamics such as a zonal wind of 50 m s−1 on the earth’s great circle, when the assimilation window has a size of 3 h. The second application is the 3D-FGAT assimilation of true ozone measurements into a chemical–transport model. It confirms the previous results, showing that the 3D-FGAT analysis with the outer loop produces an overestimation of the ozone increment in regions where the wind speed is high compared to the time length of the assimilation window.

scholarly journals Three-Dimensional Biomodels: Use of Different Materials for the Surgical Planning in Relation to Two Mandibular Cysts Cases

2020 ◽  
pp. 1-6
Author(s):  
Astigueta José Mariano ◽  
Astigueta José Mariano ◽  
Mendoza Cuello Norbin José ◽  
Benitez Javier Alejandro ◽  
Attaguile Alberto ◽  
...  
Keyword(s):  
Surgical Planning ◽  
Postoperative Morbidity ◽  
Three Dimensional ◽  
Surgical Time ◽  
Pathological Fractures ◽  
Dentigerous Cysts ◽  
3D Printers ◽  
Dimensional Models ◽  
Three Dimensional Models ◽  
The One

Introduction: The use of three-dimensional models in the diagnosis, planification and treatment of the maxillofacial area pathology has been included in publications since 1980, and has enabled to minimize surgical time, reducing peri and postoperative morbidity, and optimizing surgical results. Currently, the market offers a huge range of 3D printers and materials which allows biomodels to be printed for medical purposes. The purpose of the following paper is to describe the use of two types of three-dimensional models in the therapeutic planning of two cases of mandibular cysts. Case Report: Two cases of mandibular dentigerous cysts are described, in which osteosynthesis plates were used to prevent pathological fractures, pre-modeled together with acrylic positioners on three-dimensional models and printed in different ways. Postoperative clinical and tomographic controls were performed. Conclusion: The knowledge of the properties of the different materials available for the construction of three-dimensional models allows selecting the one that best suits the case needs required, minimizing surgical times and optimizing the results.

Modeling of Combustion in Gasoline Direct Injection Engines for the Optimization of Engine Management System Through Reduction of Three-Dimensional Models to (n × One-Dimensional) Models

2003 ◽  
Vol 125 (3) ◽  
pp. 520-532 ◽  
Author(s):  
P. Emery ◽  
F. Maroteaux ◽  
M. Sorine
Keyword(s):  
Direct Injection ◽  
Three Dimensional ◽  
Gasoline Direct Injection ◽  
Computational Time ◽  
Combustion Model ◽  
Dimensional Model ◽  
One Dimensional ◽  
Dimensional Models ◽  
Three Dimensional Models ◽  
The One

Gasoline direct injection (GDI) spark ignition engines may be able to run over a wide range of operating conditions. The GDI process allows combustion with lean mixtures which may lead to improved fuel economy and emissions relative to homogeneous spark ignition (SI) engines. To satisfy the different modes of operation, the tuning of GDI engines requires a large number of engine tests which are time-consuming and very expensive. To reduce the number of tests, a model with a very short computational time to simulate the engines in the whole operating range is needed; therefore the objective of this paper is to present a reduced model to analyze the combustion process in GDI engines, applied to a homogeneous stoichiometric mode. The objective of the model is to reproduce the same tendencies as those obtained by three-dimensional models, but with a reduced computational time. The one-dimensional model is obtained thanks to a reduction methodology based on the geometry of the combustion front computed with three-dimensional models of the KIVA-GSM code, a modified version of KIVA-II code including a CFM combustion model. The model is a set of n one-dimensional equations (i.e., for n rays), taking into account a thin flame front, described with the flamelet assumption. It includes a CFM combustion model and a (k,ε)-model including the mean air motions (swirl and tumble). The results of the one-dimensional model are compared to those obtained by the KIVA IIGSM under different engine conditions. The comparison shows that the one-dimensional model overestimates the maximum cylinder pressure, which has an insignificant effect on the net indicated work per cycle. The results obtained by the numerical simulations are close to those given by the three-dimensional model, with a much reduced computation time.

A Comparison Study of One-Dimensional Models for Stratified Thermal Storage Tanks

1989 ◽  
Vol 111 (3) ◽  
pp. 204-210 ◽  
Author(s):  
Y. H. Zurigat ◽  
K. J. Maloney ◽  
A. J. Ghajar
Keyword(s):  
Three Dimensional ◽  
Thermal Storage ◽  
Comparison Study ◽  
Storage Tanks ◽  
Factors Affecting ◽  
One Dimensional ◽  
Mixing Parameters ◽  
Dimensional Models ◽  
Three Dimensional Models ◽  
The One

A survey of the stratified thermal storage tank one-dimensional models available in the literature has been conducted. Six of these models were tested and compared against the experimental data obtained at our laboratories and from the literature. Although various factors affecting the performance of a stratified tank can be accounted for by the higher order models, i.e. two- and three-dimensional models, the introduction of empirically-based mixing parameters into the one-dimensional models renders them widely applicable and practical in the simulation of energy systems incorporating thermal storage tanks.

scholarly journals Film lessons: early cinema for historians of science

2016 ◽  
Vol 49 (2) ◽  
pp. 279-286 ◽  
Author(s):  
Jesse Olszynko-Gryn
Keyword(s):  
Social Life ◽  
Three Dimensional ◽  
Early Cinema ◽  
The Public ◽  
Digital Era ◽  
History Of ◽  
Excellent Work ◽  
Three Dimensional Models ◽  
The Public Sphere ◽  
The One

Despite much excellent work over the years, the vast history of scientific filmmaking is still largely unknown. Historians of science have long been concerned with visual culture, communication and the public sphere on the one hand, and with expertise, knowledge production and experimental practice on the other. Scientists, we know, drew pictures, took photographs and made three-dimensional models. Rather like models, films could not be printed in journals until the digital era, and this limited their usefulness as evidence. But that did not stop researchers from making movies for projection at conferences as well as in lecture halls, museums and other public venues, not to mention for breaking down into individual frames for analysis. Historians of science are more likely to be found in the library, archive or museum than the darkened screening room, and much work is still needed to demonstrate the major effects of cinema on scientific knowledge. Film may have taken as long to change science as other areas of social life, but one can begin to glimpse important ways in which ‘image machines’ (cameras, projectors and the like) were beginning to mediate between backstage experimental work and more public demonstration even around 1900.

On generalized Green’s functions in one dimension

1990 ◽  
Vol 431 (1883) ◽  
pp. 481-491
Keyword(s):  
Polymer Chain ◽  
Green's Functions ◽  
Green’S Functions ◽  
Three Dimensional ◽  
One Dimension ◽  
Asymptotic Results ◽  
One Dimensional ◽  
Three Dimensional Models ◽  
The One ◽  
Insight Into

Study of the one-dimensional polymer chain provides insight into the nature of two-and three-dimensional models. The generalized Green’s functions associated with the Domb-Joyce diagrammatic expansion in one dimension are classified and methods for determining their exact contributions are developed. The existence of confluent subdominant singularities is demonstrated in all dimensions. Exact and asymptotic results to second order are presented.

Diffraction contrast of dislocations in icosahedral quasicrystals

1990 ◽  
Vol 48 (4) ◽  
pp. 454-455
Author(s):  
K. Urban ◽  
Z. Zhang ◽  
M. Wollgarten ◽  
D. Gratias
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Complete Characterization ◽  
Extinction Condition ◽  
Burgers Vector ◽  
Diffraction Contrast ◽  
Lattice Geometry ◽  
Reference Space ◽  
Icosahedral Quasicrystals ◽  
The One

Recently dislocations have been observed by electron microscopy in the icosahedral quasicrystalline (IQ) phase of Al65Cu20Fe15. These dislocations exhibit diffraction contrast similar to that known for dislocations in conventional crystals. The contrast becomes extinct for certain diffraction vectors g. In the following the basis of electron diffraction contrast of dislocations in the IQ phase is described. Taking account of the six-dimensional nature of the Burgers vector a “strong” and a “weak” extinction condition are found.Dislocations in quasicrystals canot be described on the basis of simple shear or insertion of a lattice plane only. In order to achieve a complete characterization of these dislocations it is advantageous to make use of the one to one correspondence of the lattice geometry in our three-dimensional space (R3) and that in the six-dimensional reference space (R6) where full periodicity is recovered . Therefore the contrast extinction condition has to be written as gpbp + gobo = 0 (1). The diffraction vector g and the Burgers vector b decompose into two vectors gp, bp and go, bo in, respectively, the physical and the orthogonal three-dimensional sub-spaces of R6.

Plastic replicas as three-dimensional models of pulps

1975 ◽  
Vol 39 (8) ◽  
pp. 544-546
Author(s):  
HL Wakkerman ◽  
GS The ◽  
AJ Spanauf
Keyword(s):  
Three Dimensional ◽  
Dimensional Models ◽  
Three Dimensional Models
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