1,945 research outputs found
PERIPHERAL VS. CORE REGIONS IN EXTENDED INTEGRATED MARKETS: A PRELIMINARY U.S. APPLICATION
Community/Rural/Urban Development,
BUSINESS VOLATILITY AND ECONOMIC GROWTH IN CORE AND PERIPHERAL AREAS: UPPER MIDWEST REGION (USA) VERSUS NORDIC COUNTRIES AND BALTIC RIM
Community/Rural/Urban Development,
FMRI Clustering and False Positive Rates
Recently, Eklund et al. (2016) analyzed clustering methods in standard FMRI
packages: AFNI (which we maintain), FSL, and SPM [1]. They claimed: 1) false
positive rates (FPRs) in traditional approaches are greatly inflated,
questioning the validity of "countless published fMRI studies"; 2)
nonparametric methods produce valid, but slightly conservative, FPRs; 3) a
common flawed assumption is that the spatial autocorrelation function (ACF) of
FMRI noise is Gaussian-shaped; and 4) a 15-year-old bug in AFNI's 3dClustSim
significantly contributed to producing "particularly high" FPRs compared to
other software. We repeated simulations from [1] (Beijing-Zang data [2], see
[3]), and comment on each point briefly.Comment: 3 pages, 1 figure. A Letter accepted in PNA
Fuzzy Logic Controller Scheme for Floor Vibration Control
© 2015 Owned by the authors, published by EDP Sciences. The design of civil engineering floors is increasingly being governed by their vibration serviceability performance. This trend is the result of advancements in design technologies offering designers greater flexibilities in realising more lightweight, longer span and more open-plan layouts. These floors are prone to excitation from human activities. The present research work looks at analytical studies of active vibration control on a case study floor prototype that has been specifically designed to be representative of a real office floor structure. Specifically, it looks at tuning fuzzy control gains with the aim of adapting them to measured structural responses under human excitation. Vibration mitigation performances are compared with those of a general velocity feedback controller, and these are found to be identical in these sets of studies. It is also found that slightly less control force is required for the fuzzy controller scheme at moderate to low response levels and as a result of the adaptive gain, at very low responses the control force is close to zero, which is a desirable control feature. There is also saturation in the peak gain with the fuzzy controller scheme, with this gain tending towards the optimal feedback gain of the direct velocity feedback (DVF) at high response levels for this fuzzy design.The authors would like to acknowledge the financial
assistance provided by the UK Engineering and Physical
Sciences Research Council (EPSRC) through a
responsive mode grant (Ref. EP/H009825/1), a Platform
Grant (Ref. EP/G061130/2) and a Leadership Fellowship
Grant (Ref. EP/J004081/2). Also acknowledged are the
British Council (UK) through the Researcher Links
programme and Brazilian institutions CNPq and CAPES
financial support
Freeform Deposition Method for Coolant Channel Closeout
A method is provided for fabricating a coolant channel closeout jacket on a structure having coolant channels formed in an outer surface thereof. A line of tangency relative to the outer surface is defined for each point on the outer surface. Linear rows of a metal feedstock are directed towards and deposited on the outer surface of the structure as a beam of weld energy is directed to the metal feedstock so-deposited. A first angle between the metal feedstock so-directed and the line of tangency is maintained in a range of 20-90.degree.. The beam is directed towards a portion of the linear rows such that less than 30% of the cross-sectional area of the beam impinges on a currently-deposited one of the linear rows. A second angle between the beam and the line of tangency is maintained in a range of 5-65 degrees
The Remarkably Featureless High Resolution X-ray Spectrum of Mrk 478
An observation of Mrk 478 using the Chandra Low Energy Transmission Grating
Spectrometer is presented. The source exhibited 30-40% flux variations on
timescales of order 10000 s together with a slow decline in the spectral
softness over the full 80 ks observation. The 0.15--3.0 keV spectrum is well
fitted by a single power law with photon index of Gamma = 2.91 +/- 0.03.
Combined with high energy data from BeppoSAX, the spectrum from 0.15 to 10 keV
is well fit as the sum of two power laws with Gamma = 3.03 +/- 0.04, which
dominates below 2 keV and 1.4 +/- 0.2, which dominates above 2 keV (quoting 90%
confidence uncertainties). No significant emission or absorption features are
detected in the high resolution spectrum, supporting our previous findings
using the Extreme Ultraviolet Explorer but contradicting the claims of emission
lines by Hwang & Bowyer (1997). There is no evidence of a warm absorber, as
found in the high resolution spectra of many Sy 1 galaxies including others
classified as narrow line Sy 1 galaxies such as Mrk 478. We suggest that the
X-ray continuum may result from Comptonization of disk thermal emission in a
hot corona through a range of optical depths.Comment: 21 pages, 7 figures; accepted for publication in the Astronomical
Journa
Developmental lung expression and transcriptional regulation of Claudin-6 by TTF-1, Gata-6, and FoxA2
Damage detection in concrete precast slabs: A quick assessment through modal tests
© 2015 Owned by the authors, published by EDP Sciences. The use of modal tests for detecting damage in reinforced concrete precast slabs is evaluated. A set of eight slabs were tested, each belonging to flats constructed for residential use. Two groups of slabs were identified and, in each group, both cracked and uncracked slabs were found. This made it possible to compare the responses of the slabs when subjected to modal tests. The tests were carried out employing an instrumented hammer and heel drops as excitation sources. Responses were measured using an accelerometer. The lowest natural frequencies of the slabs could be identified and after filtering the results, plots indicating the variation of the lowest natural frequency versus the number of cycles of free decay were obtained for each slab. Such a plot is of more general use than the value of the natural frequency by itself, as it does not depend on slab configuration. It was observed that the cracked slabs presented a similar pattern of variation of the natural frequencies throughout the decay, being distinctive from the pattern observed for their uncracked counterparts. This provided evidence that a quick assessment of the structural condition of such slabs through the use of the tests were feasible.The authors acknowledge both Brazilian institutions
CNPq and CAPES, and the British Council (UK) through
the Researcher Links programme, for the financial
support for this research work
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