scholarly journals On the quasi‐three dimensional configuration of magnetic clouds

2020 ◽  
Author(s):  
Q. Hu ◽  
W. He ◽  
J. Qiu ◽  
A. Vourlidas ◽  
C. Zhu
Keyword(s):  
Three Dimensional ◽  
Magnetic Clouds ◽  
Three Dimensional Configuration

scholarly journals Improvement on Permeability of Cyclic Peptide/Peptidomimetic: Backbone N-Methylation as A Useful Tool

Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 311
Author(s):  
Yang Li ◽  
Wang Li ◽  
Zhengshuang Xu
Keyword(s):  
Cyclic Peptides ◽  
Cyclic Peptide ◽  
Three Dimensional ◽  
Conformational Space ◽  
Cell Permeability ◽  
Relative Importance ◽  
Intrinsic Properties ◽  
Surface Areas ◽  
Synthetic Methodologies ◽  
Three Dimensional Configuration

Peptides have a three-dimensional configuration that can adopt particular conformations for binding to proteins, which are well suited to interact with larger contact surface areas on target proteins. However, low cell permeability is a major challenge in the development of peptide-related drugs. In recent years, backbone N-methylation has been a useful tool for manipulating the permeability of cyclic peptides/peptidomimetics. Backbone N-methylation permits the adjustment of molecule’s conformational space. Several pathways are involved in the drug absorption pathway; the relative importance of each N-methylation to total permeation is likely to differ with intrinsic properties of cyclic peptide/peptidomimetic. Recent studies on the permeability of cyclic peptides/peptidomimetics using the backbone N-methylation strategy and synthetic methodologies will be presented in this review.

Pit pattern and three-dimensional configuration of isolated crypts from the patients with colorectal neoplasm

2002 ◽  
Vol 37 (10) ◽  
pp. 798-806 ◽  
Author(s):  
Satoru Tamura ◽  
Yasuo Furuya ◽  
Takehisa Tadokoro ◽  
Yoshifumi Higashidani ◽  
Yuichi Yokoyama ◽  
...  
Keyword(s):  
Colorectal Neoplasm ◽  
Three Dimensional ◽  
Pit Pattern ◽  
Three Dimensional Configuration

Three-Dimensional Configuration of Subretinal Fluid in Central Serous Chorioretinopathy

2013 ◽  
Vol 54 (9) ◽  
pp. 5944 ◽  
Author(s):  
Soh-Eun Ahn ◽  
Jaeryung Oh ◽  
Jong-Hyun Oh ◽  
In Kyung Oh ◽  
Seong-Woo Kim ◽  
...  
Keyword(s):  
Central Serous Chorioretinopathy ◽  
Three Dimensional ◽  
Subretinal Fluid ◽  
Three Dimensional Configuration

Dielectric Metrology VIA Microwave Tomography: Present and Future

1994 ◽  
Vol 347 ◽  
Author(s):  
J.Ch. Bolomey ◽  
N. Joachimowicz
Keyword(s):  
Inverse Scattering ◽  
A Priori ◽  
Scattering Problem ◽  
Measurement Techniques ◽  
Three Dimensional ◽  
Inverse Scattering Problem ◽  
Dielectric Characterization ◽  
Sample Shape ◽  
Three Dimensional Configuration ◽  
Characterization Of Materials

ABSTRACTUntil now, the measurement techniques used for the dielectric characterization of materials require severe limitations in terms of sample shape, size and homogeneity. This paper considers the dielectric permittivity measurement as a non-linear inverse scattering problem. Such an approach allows to identify the quantities to be measured and suggests possible experimental arrangements. The problem is shown to be significantly simplified if the shape of the material is known and if some a priori knowledge of the averaged value of the permittivity in the material under test is available. Two test cases have been selected to illustrate the state of the art in solving such inverse problems. The first one consists of a two-dimensional configuration which is applicable to cylindrical objects, and the second one to a vector three-dimensional configuration applicable, for instance, to cubic samples. The main limitations of such an inverse scattering approach are discussed and expected improvements in the near future are analysed.

Computation of Viscous Flow Around Propeller-Body Configurations: Series 60 CB = 0.6 Ship Model

1994 ◽  
Vol 38 (02) ◽  
pp. 137-157 ◽  
Author(s):  
F. Stern ◽  
H. T. Kim ◽  
D. H. Zhang ◽  
Y. Toda ◽  
J. Kerwin ◽  
...  
Keyword(s):  
Viscous Flow ◽  
Turbulence Modeling ◽  
Critical Evaluation ◽  
Three Dimensional ◽  
Inviscid Flow ◽  
Ship Model ◽  
Flow Method ◽  
Critical Issues ◽  
Three Dimensional Configuration ◽  
Extensive Experimental Data

Validation of a viscous-flow method for predicting propeller-hull interaction is provided through detailed comparisons with recent extensive experimental data for the practical three-dimensional configuration of the Series 60 CB = 0.6 ship model. Modifications are made to the k-e turbulence model for the present geometry and application. Agreement is demonstrated between the calculations and global and some detailed aspects of the data; however, very detailed resolution of the flow is lacking. This supports the previous conclusion for propeller-shaft configurations and axisymmetric bodies that the present procedures can accurately simulate the steady part of the combined propeller-hull flow field, although turbulence modeling and detailed numerical treatments are critical issues. The present application enables a more critical evaluation through further discussion of these and other relevant issues, such as the use of radial-and angular-varying body-force distributions, the relative importance of turbulence modeling and grid density on the resolution of the harmonics of the propeller inflow, and three-dimensional propeller-hull interaction, including the differences for the nominal and effective inflows and for the resulting steady and unsteady propeller performance. Also, comparisons are made with an inviscid-flow method. Lastly, some concluding remarks are made concerning the limitations of the method, requirements and prognosis for improvements, and application to the design of wake-adapted propellers.

Dynamics of Compliant Risers

1990 ◽  
Vol 34 (02) ◽  
pp. 123-135
Author(s):  
N. M. Patrikalakis ◽  
G. A. Kriezis ◽  
H. N. Gursoy ◽  
T. Maekawa
Keyword(s):  
Three Dimensional ◽  
Small Scale ◽  
Nonlinear Boundary Value Problems ◽  
Restoring Force ◽  
Numerical Solution Method ◽  
Quadratic Drag ◽  
Theoretical Predictions ◽  
Nonlinear Force ◽  
Nonlinear Static ◽  
Three Dimensional Configuration

The objective of this paper is first to formulate the three-dimensional dynamic equations of a compliant riser, idealized as a rotationally nonuniform rod, around a nonlinear static configuration with linearized restoring force and inertial components in the presence of general current and monochromatic wave excitation. Next, to harmonically linearize nonlinear forces such as quadratic drag for the general three-dimensional problem by minimizing the mean square error between the linear approximation and the nonlinear force. Finally, to present an efficient numerical solution method appropriate for nonlinear boundary-value problems with sharp boundary layers such as the problem at hand. Numerical examples and comparisons with time-domain solutions for a catenary riser with a three-dimensional configuration and a steep-wave riser are included. Comparisons of our theoretical predictions with experimental results obtained from a small-scale riser model are also summarized to evaluate our theoretical ability to predict the response of compliant riser systems.

scholarly journals A monolithic algorithm for the flow simulation of flexible flapping wings

2019 ◽  
Vol 11 ◽  
pp. 175682931984612 ◽  
Author(s):  
Tao Yang ◽  
Mingjun Wei ◽  
Kun Jia ◽  
James Chen
Keyword(s):  
Three Dimensional ◽  
Flow Simulation ◽  
Flapping Wings ◽  
Rigid Sphere ◽  
Two Dimensional ◽  
Unified Framework ◽  
Fluid Structure ◽  
A Cell ◽  
Three Dimensional Configuration ◽  
The Impact

It has been a challenge to simulate flexible flapping wings or other three-dimensional problems involving strong fluid–structure interactions. Solving a unified fluid–solid system in a monolithic manner improves both numerical stability and efficiency. The current algorithm considered a three-dimensional extension of an earlier work which formulated two-dimensional fluid–structure interaction monolithically under a unified framework for both fluids and solids. As the approach is extended from a two-dimensional to a three-dimensional configuration, a cell division technique and the associated projection process become necessary and are illustrated here. Two benchmark cases, a floppy viscoelastic particle in shear flow and a flow passing a rigid sphere, are simulated for validation. Finally, the three-dimensional monolithic algorithm is applied to study a micro-air vehicle with flexible flapping wings in a forward flight at different angles of attack. The simulation shows the impact from the angle of attack on wing deformation, wake vortex structures, and the overall aerodynamic performance.

scholarly journals Comparison of Multivariate Analysis Methods as Applied to English Speech

2020 ◽  
Vol 10 (20) ◽  
pp. 7076
Author(s):  
Yixin Zhang ◽  
Yoshitaka Nakajima ◽  
Kazuo Ueda ◽  
Takuya Kishida ◽  
Gerard B. Remijn
Keyword(s):  
Factor Analysis ◽  
Multivariate Analyses ◽  
Three Dimensional ◽  
Speech Acoustics ◽  
Spectral Changes ◽  
Acoustic Correlates ◽  
New Finding ◽  
Three Dimensional Configuration ◽  
First Time ◽  
Spectral Factor

A newly developed factor analysis, origin-shifted factor analysis, was compared with a normal factor analysis to analyze the spectral changes of English speech. Our first aim was to investigate whether these analyses would cause differences in the factor loadings and the extracted spectral-factor scores. The methods mainly differed in whether to use cepstral liftering and an origin shift. The results showed that three spectral factors were obtained in four main frequency bands, but neither the cepstral liftering nor the origin shift distorted the essential characteristics of the factors. This confirms that the origin-shifted factor analysis is more recommendable for future speech analyses, since it would reduce the generation of noise in resynthesized speech. Our second aim was to further identify acoustic correlates of English phonemes. Our data show for the first time that the distribution of obstruents in English speech constitutes an L-shape related to two spectral factors on the three-dimensional configuration. One factor had center loadings around 4100 Hz, while the other was bimodal with peaks around 300 Hz and 2300 Hz. This new finding validates the use of multivariate analyses to connect English phonology and speech acoustics.

scholarly journals 3D turbulent reconnection driven current-sheet dynamics: solar applications

2010 ◽  
Vol 6 (S274) ◽  
pp. 458-460
Author(s):  
Lapo Bettarini ◽  
Giovanni Lapenta
Keyword(s):  
Current Sheet ◽  
Characteristic Time ◽  
Three Dimensional ◽  
Reynolds Numbers ◽  
Anomalous Effect ◽  
Instability Modes ◽  
Diffusive Dynamics ◽  
Three Dimensional Configuration ◽  
A Current ◽  
Dimensional Picture

AbstractWe provide a complete three-dimensional picture of the reconnecting dynamics of a current-sheet. Recently, a two-dimensional non-steady reconnection dynamics has been proved to occur without the presence of any anomalous effect (Lapenta, 2008, Skender & Lapenta, 2010, Bettarini & Lapenta, 2010) but such a picture must be confirmed in a full three-dimensional configuration wherein all instability modes are allowed to drive the evolution of the system, i.e. to sustain a reconnection dynamics or to push the system along a different instability path. Here we propose a full-space analysis allowing us to determine the longitudinal and, possibly, the transversal modes driving the different current-sheet disruption regimes, the corresponding characteristic time-scales and to study system's instability space- parameter (plasma beta, Lundquist and Reynolds numbers, system's aspect ratio). The conditions leading to an explosive evolution rather then to a diffusive dynamics as well as the details of the reconnection inflow/outflow regime at the disruption phase are determined. Such system embedded in a solar-like environment and undergoing a non-steady reconnection evolution may determine the formation both of jets and waves influencing the dynamics and energetic of the upper layers and of characteristic down-flows as observed in the low solar atmosphere.

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