748 research outputs found
AAS227 - Synthesizing Understanding from Data with yt
No full textThis is a talk I gave at the AAS227 about yt. yt is available at yt-project.org.<div><br></div><div>While I am listed as the author of this talk, the yt community is composed of more than a hundred code contributors and mailing list participants, and we are grateful to their involvement and support.</div><div><br></div><div>Additionally, the yt project is built on other members of the scientific software ecosystem such as Jupyter, NumPy, Cython, h5py and hdf5, Matplotlib, and Sympy.</div
Correction to: Chemoradiation in elderly patients with glioblastoma from the multiinstitutional GBMmolRPA cohort: is shortcourse radiotherapy enough or is it a matter of selection?
No full textThe name of author Do Hoon Lim was incorrect in the initial online publication. The original article has been corrected
Locally averaged temperature dissipation rate in turbulent convection.
Full text linkKwok Chun-yin.Thesis (M.Phil.)--Chinese University of Hong Kong, 2000.Includes bibliographical references (leaves [121]-122).Abstracts in English and Chinese.Chapter 1 --- Introduction --- p.1Chapter 2 --- Experimental data --- p.7Chapter 2.1 --- Turbulent Convection using Helium --- p.7Chapter 2.2 --- Turbulent Convection using water --- p.8Chapter 3 --- Probability Distribution and Scaling behavior --- p.9Chapter 3.1 --- PDF of YT --- p.9Chapter 3.1.1 --- Helium Convection --- p.10Chapter 3.1.2 --- Water Convection --- p.26Chapter 3.1.3 --- Comparison between helium data and Water data --- p.34Chapter 3.2 --- T -dependence of the moments of XT --- p.39Chapter 3.2.1 --- Helium Convection --- p.39Chapter 3.2.2 --- Water Convection --- p.47Chapter 4 --- Hierarchical Moment Relation --- p.50Chapter 4.1 --- Method of Analysis --- p.50Chapter 4.2 --- Results and Discussion --- p.53Chapter 4.2.1 --- Helium Convection --- p.53Chapter 4.2.2 --- Water Convection --- p.81Chapter 5 --- Discussion and Conclusion --- p.95Chapter 5.1 --- Passive Scalar --- p.96Chapter 5.2 --- Comparison between Turbulent Convection and Passive Scalar --- p.99Chapter 5.3 --- Scaling behavior for length scale above and below the Bolgiano scale for turbulent convection using Helium gas --- p.100Chapter 5.4 --- Conclusions --- p.107Chapter A --- The lognormal model --- p.108Chapter B --- Definition of XT --- p.110Chapter C --- Reasons for analysis of (xTp) for p≤ 12 --- p.112Chapter D --- Functional form of μp implied by the hierarchical relation --- p.119Bibliography --- p.12
Effect of donepezil on transcranial magnetic stimulation parameters in Alzheimer's disease
Full text linkIntroduction: There is a need for a reliable, noninvasive biomarker for Alzheimer's disease (AD). We assessed whether short-latency afferent inhibition (SAI), a transcranial magnetic stimulation paradigm that assesses cholinergic circuits of the brain, could become such a biomarker.
Methods: Nineteen patients with AD underwent four SAI testing sessions. The timing of their usual donepezil dose was altered to create different cholinergic states for each session. This was compared to the SAI results from 20 healthy subjects.
Results: SAI was not able to distinguish the different cholinergic states assessed in our study. There appeared to be a diurnal variation in cholinergic function in the control group, which was not present in the AD cohort.
Discussion: SAI does not appear to have a role in diagnosis and assessment of AD patients. The loss of diurnal variation, however, warrants further investigation as it may provide further biochemical insights about AD
Can Cause and Effect be Distinguised by Simple Regression? ESRI Memorandum Series No. 50 (revised) 1968(?)
Full text linkLet data be (Xt, Yt), t = 1, 2, ..., T. We assume throughout that T is "large". We try to evolve statistical tests for identifying whether X or Y is the cause, the other variable being the effect
Scaling relationships in indentation of power-law creep solids using self-similar indenters
No full textWe use dimensional analysis to derive scaling relationships for self-similar indenters indenting solids that exhibit power-law creep. We identify the parameter that represents the indentation strain rate. The scaling relationships are applied to several types of indentation creep experiment with constant displacement rate, constant loading rate or constant ratio of loading rate over load. The predictions compare favourably with experimental observations reported in the literature. Finally, a connection is found between creep and 'indentation-size effect' (i.e. changing hardness with indentation depth or load)
Nonlinear Analysis of Oscillatory Indentation in Elastic and Viscoelastic Solids
No full textDetermining the mechanical properties at micro- and nanometer length scales using nanoindentation or atomic force microscopy is important to many areas of science and engineering. Here we establish equations for obtaining storage and loss modulus from oscillatory indentations by performing a nonlinear analysis of conical and spherical indentation in elastic and viscoelastic solids. We show that, when the conical indenter is driven by a sinusoidal force, the square of displacement is a sinusoidal function of time, not the displacement itself, which is commonly assumed. Similar conclusions hold for spherical indentations. Well-known difficulties associated with measuring contact area and correcting thermal drift may be circumvented using the newly derived equations. These results may help improve methods of using oscillatory indentation for determining elastic and viscoelastic properties of solids
Equivalent formula of S4 system & its application in NLU & TMT
No full textIn this paper we first give a brief introduction to the basic concepts of TMT and S4 system. Now a small TMT prototype is being built up in SIA which is funded by CAS. Then author presents a safest way to transform some natural language form each other which is called the duality-drived-equivalent formula that uses unambiguous-natural-language-like-4th-class-symbols and is drived out based on the duality principles. Duality-drived-equivalent formula are of absolutely correctness that needn't to consider the context, so it can be used in TMT-trustworthy machine translation-system to guarantee the correctness of MT
What is indentation hardness?
Full text linkUsing dimensional analysis and finite element calculations, we derive simple scaling relationships for loading and unloading curve, contact depth, and hardness. The relationship between hardness and the basic mechanical properties of solids, such as Young's modulus, initial yield strength, and work-hardening exponent, is then obtained. The conditions for 'piling-up' and 'sinking-in' of surface profiles during indentation are determined. A method for estimating contact depth from initial unloading slope is examined. The work done during indentation is also studied. A relationship between the ratio of hardness to elastic modulus and the ratio of irreversible work to total work is discovered. This relationship offers a new method for obtaining hardness and elastic modulus. Finally, a scaling theory for indentation in power-law creep solids using self-similar indenters is developed. A connection between creep and 'indentation size effect' is established
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