scholarly journals One-dimensional wavefront sensor development for tomographic flow measurements

1995 ◽  
Author(s):  
Daniel R. Neal ◽  
Robert E. Pierson ◽  
E. Chen ◽  
Kenneth P. Bishop ◽  
Lenore J. McMackin
Keyword(s):  
Wavefront Sensor ◽  
Flow Measurements ◽  
One Dimensional ◽  
Sensor Development

scholarly journals Optimization of topological complexity for one-dimensional arterial blood flow models

2018 ◽  
Vol 15 (149) ◽  
pp. 20180546 ◽  
Author(s):  
Fredrik E. Fossan ◽  
Jorge Mariscal-Harana ◽  
Jordi Alastruey ◽  
Leif R. Hellevik
Keyword(s):  
Blood Flow ◽  
Pulse Pressure ◽  
Arterial System ◽  
Arterial Blood Flow ◽  
Patient Specific ◽  
Flow Measurements ◽  
One Dimensional ◽  
Flow Models ◽  
Arterial Blood ◽  
Blood Flow Models

As computational models of the cardiovascular system are applied in modern personalized medicine, maximizing certainty of model input becomes crucial. A model with a high number of arterial segments results in a more realistic description of the system, but also requires a high number of parameters with associated uncertainties. In this paper, we present a method to optimize/reduce the number of arterial segments included in one-dimensional blood flow models, while preserving key features of flow and pressure waveforms. We quantify the preservation of key flow features for the optimal network with respect to the baseline networks (a 96-artery and a patient-specific coronary network) by various metrics and quantities like average relative error, pulse pressure and augmentation pressure. Furthermore, various physiological and pathological states are considered. For the aortic root and larger systemic artery pressure waveforms a network with minimal description of lower and upper limb arteries and no cerebral arteries, sufficiently captures important features such as pressure augmentation and pulse pressure. Discrepancies in carotid and middle cerebral artery flow waveforms that are introduced by describing the arterial system in a minimalistic manner are small compared with errors related to uncertainties in blood flow measurements obtained by ultrasound.

scholarly journals MAPPIT 2: Second Generation High-resolution Imaging at the AAT

1997 ◽  
Vol 14 (2) ◽  
pp. 189-194
Author(s):  
J. G. Robertson
Keyword(s):  
Spatial Resolution ◽  
Speckle Interferometry ◽  
Wavefront Sensor ◽  
One Dimension ◽  
High Resolution Imaging ◽  
Complex Objects ◽  
One Dimensional ◽  
Resolution Imaging ◽  
Ccd Detectors ◽  
Optical Telescopes

AbstractInterferometric methods have been used at a number of observatories to improve the spatial resolution of large optical telescopes, approaching and in some cases reaching the diffraction limit. The principal methods used have been speckle interferometry and non-redundant masking (NRM). The MAPPIT (Masked APerture Plane Interference Telescope) instrument has been used for NRM observations at the 3·9 m Anglo-Australian Telescope. This paper describes a proposed instrument, MAPPIT 2, which would use a Shack-Hartmann wavefront sensor in parallel with an interferometer performing NRM or one-dimensional speckle interferometry. The inclusion of the data from the wavefront sensor will enhance the sensitivity of the instrument, especially for the imaging of relatively complex objects (those giving more than a few resolution elements with non-zero intensities). Limiting the instantaneous spatial resolution to one dimension allows available CCD detectors to operate with 100% duty cycle. Observations at a number of position angles allow two-dimensional images to be obtained.

X-ray digital wavefront sensor development

2010 ◽  
Vol 616 (2-3) ◽  
pp. 255-260
Author(s):  
Mourad Idir ◽  
Sébastien Fricker ◽  
Mohammed H. Modi ◽  
Jonathan Potier
Keyword(s):  
Wavefront Sensor ◽  
X Ray ◽  
Sensor Development

Zero Noise Wavefront Sensor Development within the Opticon European Network

2006 ◽  
pp. 315-320
Author(s):  
Philippe Feautrier ◽  
Thierry Fusco ◽  
Mark Downing ◽  
Norbert Hubin ◽  
Jean-Luc Gach ◽  
...  
Keyword(s):  
Wavefront Sensor ◽  
European Network ◽  
Sensor Development

A one-dimensional self-gravitating stellar gas

1966 ◽  
Vol 25 ◽  
pp. 46-48 ◽  
Author(s):  
M. Lecar
Keyword(s):  
Gravitational Field ◽  
Phase Space ◽  
Motion Picture ◽  
Space Distribution ◽  
Two Dimensional ◽  
One Dimensional ◽  
Phase Space Distribution ◽  
Dimensional Phase Space ◽  
The Mean

“Dynamical mixing”, i.e. relaxation of a stellar phase space distribution through interaction with the mean gravitational field, is numerically investigated for a one-dimensional self-gravitating stellar gas. Qualitative results are presented in the form of a motion picture of the flow of phase points (representing homogeneous slabs of stars) in two-dimensional phase space.

Electron-Mirror Microscopic Aspects of Ferroelectric Domains of BaTiO3 And Ca2Sr (C2H5CO2)6

1970 ◽  
Vol 28 ◽  
pp. 478-479
Author(s):  
Teruo Someya ◽  
Jinzo Kobayashi
Keyword(s):  
Surface Layer ◽  
Electric Fields ◽  
Quantitative Study ◽  
Recent Progress ◽  
Ferroelectric Domain ◽  
Resolving Power ◽  
Surface Pattern ◽  
Crystal Surfaces ◽  
One Dimensional ◽  
Ferroelectric Domains

Recent progress in the electron-mirror microscopy (EMM), e.g., an improvement of its resolving power together with an increase of the magnification makes it useful for investigating the ferroelectric domain physics. English has recently observed the domain texture in the surface layer of BaTiO3. The present authors ) have developed a theory by which one can evaluate small one-dimensional electric fields and/or topographic step heights in the crystal surfaces from their EMM pictures. This theory was applied to a quantitative study of the surface pattern of BaTiO3).

Structure and function of neural networks in the retina

1988 ◽  
Vol 46 ◽  
pp. 26-27
Author(s):  
Peter Sterling
Keyword(s):  
Ganglion Cells ◽  
Three Dimensional ◽  
Structure And Function ◽  
Synaptic Connections ◽  
Visual Axis ◽  
One Dimensional ◽  
Cat Retina ◽  
Ultrathin Sections ◽  
And Function ◽  
Insight Into

The synaptic connections in cat retina that link photoreceptors to ganglion cells have been analyzed quantitatively. Our approach has been to prepare serial, ultrathin sections and photograph en montage at low magnification (˜2000X) in the electron microscope. Six series, 100-300 sections long, have been prepared over the last decade. They derive from different cats but always from the same region of retina, about one degree from the center of the visual axis. The material has been analyzed by reconstructing adjacent neurons in each array and then identifying systematically the synaptic connections between arrays. Most reconstructions were done manually by tracing the outlines of processes in successive sections onto acetate sheets aligned on a cartoonist's jig. The tracings were then digitized, stacked by computer, and printed with the hidden lines removed. The results have provided rather than the usual one-dimensional account of pathways, a three-dimensional account of circuits. From this has emerged insight into the functional architecture.

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