The application of simulation method in one dimension pipeline flow based on elastic pipeline: The application of simulation method in one dimension pipeline flow based on elastic pipeline

1973 ◽

Vol 31 ◽

pp. 268-269

Author(s):

Elrnar Zeitler

Keyword(s):

Unit Area ◽

Three Dimensional ◽

One Dimension ◽

Spatial Density ◽

Dimensional Representation ◽

Orthogonal Functions ◽

Object A ◽

Plane Normal ◽

Dimensional Object ◽

Spatial Density Distribution

Considering any finite three-dimensional object, a “projection” is here defined as a two-dimensional representation of the object's mass per unit area on a plane normal to a given projection axis, here taken as they-axis. Since the object can be seen as being built from parallel, thin slices, the relation between object structure and its projection can be reduced by one dimension. It is assumed that an electron microscope equipped with a tilting stage records the projectionWhere the object has a spatial density distribution p(r,ϕ) within a limiting radius taken to be unity, and the stage is tilted by an angle 9 with respect to the x-axis of the recording plane.

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Quantitative Diameter Measurements of Chromatin and TMV Fibers in the Freeze-Dried State

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102936 ◽

1988 ◽

Vol 46 ◽

pp. 170-171

Author(s):

B. D. Athey ◽

A. L. Stout ◽

M. F. Smith ◽

J. P. Langmore

Keyword(s):

Reliable Method ◽

Fiber Diameter ◽

Quantitative Agreement ◽

One Dimension ◽

Fiber Axis ◽

Two Dimensional ◽

Fiber Density ◽

Variable Diameter ◽

Freeze Dried ◽

Expected Values

Although there is general agreement that Inactive chromosome fibers consist of helically packed nucleosomes, the pattern of packing is still undetermined. Only one of the proposed models, the crossed-linker model, predicts a variable diameter dependent on the length of DNA between nucleosomes. Measurements of the fiber diameter of negatively-stained and frozen- hydrated- chromatin from Thyone sperm (87bp linker) and Necturus erythrocytes (48bp linker) have been previously reported from this laboratory. We now introduce a more reliable method of measuring the diameters of electron images of fibrous objects. The procedure uses a modified version of the computer program TOTAL, which takes a two-dimensional projection of the fiber density (represented by the micrograph itself) and projects it down the fiber axis onto one dimension. We illustrate this method using high contrast, in-focus STEM images of TMV and chromatin from Thyone and Necturus. The measured diameters are in quantitative agreement with the expected values for the crossed-linker model for chromatin structure

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Power of Modified Brown-Forsythe and Mixed-Model Approaches in Split-Plot Designs

Methodology ◽

10.1027/1614-2241/a000124 ◽

2017 ◽

Vol 13 (1) ◽

pp. 9-22 ◽

Cited By ~ 1

Author(s):

Pablo Livacic-Rojas ◽

Guillermo Vallejo ◽

Paula Fernández ◽

Ellián Tuero-Herrero

Keyword(s):

Repeated Measures ◽

Statistical Power ◽

Mixed Model ◽

Covariance Structure ◽

Simulation Method ◽

Future Research ◽

Repeated Measures Design ◽

Fixed And Random Effects ◽

Split Plot ◽

High Level

Abstract. Low precision of the inferences of data analyzed with univariate or multivariate models of the Analysis of Variance (ANOVA) in repeated-measures design is associated to the absence of normality distribution of data, nonspherical covariance structures and free variation of the variance and covariance, the lack of knowledge of the error structure underlying the data, and the wrong choice of covariance structure from different selectors. In this study, levels of statistical power presented the Modified Brown Forsythe (MBF) and two procedures with the Mixed-Model Approaches (the Akaike’s Criterion, the Correctly Identified Model [CIM]) are compared. The data were analyzed using Monte Carlo simulation method with the statistical package SAS 9.2, a split-plot design, and considering six manipulated variables. The results show that the procedures exhibit high statistical power levels for within and interactional effects, and moderate and low levels for the between-groups effects under the different conditions analyzed. For the latter, only the Modified Brown Forsythe shows high level of power mainly for groups with 30 cases and Unstructured (UN) and Autoregressive Heterogeneity (ARH) matrices. For this reason, we recommend using this procedure since it exhibits higher levels of power for all effects and does not require a matrix type that underlies the structure of the data. Future research needs to be done in order to compare the power with corrected selectors using single-level and multilevel designs for fixed and random effects.

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POSSIBLE FERROMAGNETISM OF AN ELECTRON PAIR IN ONE DIMENSION

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19786317 ◽

1978 ◽

Vol 39 (C6) ◽

pp. C6-713-C6-714

Author(s):

S. Olszewski

Keyword(s):

Electron Pair ◽

One Dimension

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Pipeline Flow-Diversion Technology for the Treatment of ICA Pseudoaneurysms of Varying Etiology: Three Case Reports and Review

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0033-1336330 ◽

2013 ◽

Vol 74 (S 01) ◽

Author(s):

Hesham Soliman ◽

Koji Ebersole ◽

Chris Moran ◽

Paul Camarata

Keyword(s):

Case Reports ◽

Flow Diversion ◽

Pipeline Flow

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Effect of CT-based attenuation correction on uptake ratios in skeletal SPECT

Nuklearmedizin ◽

10.1055/s-0037-1616624 ◽

2007 ◽

Vol 46 (01) ◽

pp. 38-42 ◽

Cited By ~ 12

Author(s):

V. Schulz ◽

I. Nickel ◽

A. Nömayr ◽

A. H. Vija ◽

C. Hocke ◽

...

Keyword(s):

Vertebral Body ◽

Facet Joint ◽

One Dimension ◽

Patient Specific ◽

Data Sets ◽

Facet Joints ◽

Lumbar Vertebral Body ◽

Ct System ◽

Ct Data ◽

Attenuation Corrected

SummaryThe aim of this study was to determine the clinical relevance of compensating SPECT data for patient specific attenuation by the use of CT data simultaneously acquired with SPECT/CT when analyzing the skeletal uptake of polyphosphonates (DPD). Furthermore, the influence of misregistration between SPECT and CT data on uptake ratios was investigated. Methods: Thirty-six data sets from bone SPECTs performed on a hybrid SPECT/CT system were retrospectively analyzed. Using regions of interest (ROIs), raw counts were determined in the fifth lumbar vertebral body, its facet joints, both anterior iliacal spinae, and of the whole transversal slice. ROI measurements were performed in uncorrected (NAC) and attenuation-corrected (AC) images. Furthermore, the ROI measurements were also performed in AC scans in which SPECT and CT images had been misaligned by 1 cm in one dimension beforehand (ACX, ACY, ACZ). Results: After AC, DPD uptake ratios differed significantly from the NAC values in all regions studied ranging from 32% for the left facet joint to 39% for the vertebral body. AC using misaligned pairs of patient data sets led to a significant change of whole-slice uptake ratios whose differences ranged from 3,5 to 25%. For ACX, the average left-to-right ratio of the facet joints was by 8% and for the superior iliacal spines by 31% lower than the values determined for the matched images (p <0.05). Conclusions: AC significantly affects DPD uptake ratios. Furthermore, misalignment between SPECT and CT may introduce significant errors in quantification, potentially also affecting leftto- right ratios. Therefore, at clinical evaluation of attenuation- corrected scans special attention should be given to possible misalignments between SPECT and CT.

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