830 research outputs found
A hierarchical, fuzzy inference approach to data filtration and feature prioritization in the connected manufacturing enterprise
In manufacturing, the technology to capture and store large volumes of data developed earlier and faster than corresponding capabilities to analyze, interpret, and apply it. The result for many manufacturers is a collection of unanalyzed data and uncertainty with respect to where to begin. This paper examines big data as both an enabler and a challenge for the connected manufacturing enterprise and presents a framework that sequentially tests and selects independent variables for training applied machine learning models. Unsuitable features are discarded, and each remaining feature receives a crisp numeric output and a linguistic label, both of which are measures of the feature’s suitability. The framework is tested using three datasets employing time series, binary, and continuous input data. Results of filtered models are compared to results obtained by base, unfiltered sets of features using a proposed metric of performance-size ratio. Framework results outperform base feature sets in all tested cases, and the proposed future research will be to implement it in a case study in the electronic assembly manufacture
Pulmonary rehabilitation in chronic obstructive pulmonary disease: Outcomes in a 12 week programme
Infrared Imaging of Capella with the IOTA Closure Phase Interferometer
We present infrared aperture synthesis maps produced with the upgraded IOTA
interferometer. Michelson interferograms on the close binary system Capella
(Alpha Aur) were obtained in the H-band between 2002 November 12 and 16 using
the IONIC3 beam combiner. With baselines of 15m < B < 38m, we were able to
determine the relative position of the binary components with milliarcsecond
(mas) precision and to track their movement along the approx. 14 degree arc
covered by our observation run. We briefly describe the algorithms used for
visibility and closure phase estimation. Three different Hybrid Mapping and
Bispectrum Fitting techniques were implemented within one software framework
and used to reconstruct the source brightness distribution. By dividing our
data into subsets, the system could be mapped at three epochs, revealing the
motion of the stars. The precise position of the binary components was also
determined with model fits, which in addition revealed I_Aa/I_Ab=1.49 +/- 0.10
and apparent stellar uniform-disk (UD) diameters of Theta_Aa=8.9 +/- 0.6 mas
and Theta_Ab=5.8 +/- 0.8 mas.
To improve the u, v-plane coverage, we compensated this orbital motion by
applying a rotation-compensating coordinate transformation. The resulting
model-independent map with a beam size of 5.4 x 2.6 mas allows the resolution
of the stellar surfaces of the Capella giants themselves.Comment: Accepted by the Astronomical Journal (2005-03-21
Overwintering aggregations of Leiobunum paessleri in caves and mines (Arachnida, Opiliones).
In the forested mountain areas of southwestern Canada, Leiobunull1 paessleri (Roewer) form
overwintering aggregations in the twilight regions of moist caves and mines. Each aggregation consists
of adults of both sexes and may contain as many as one or two thousand individuals. The opilionids
congregate from August to October and disperse from April to May. Colder temperatures seem to
increase the density of the aggregations. When dense aggregations are formed (up to 2.6 individuals
per em'), the opilionids hang by their pedipalps with their legs extended straight down from their
bodies. Explanations of the aggregation phenomenon include: optimal temperatures and humidities,
reduced desiccation, heat production, increased mating success, and reduced predation. Overwintering
mortality factors potentially include cold, desiccation, starvation, predation and disease
Mammary cell activity and turnover in dairy cows treated with the prolactin-release inhibitor quinagolide and milked once daily
To assess the regulation of mammary cell activity, survival, and proliferation by prolactin (PRL), 5 Holstein cows in early lactation received daily i.m. injections of 1 mg of quinagolide, a suppressor of PRL release, for 9 wk, whereas 4 control cows received the vehicle (water) only. During the last week of treatment, one udder half was milked once a day (1×) and the other twice a day (2×). Mammary biopsies were harvested 1 wk before and 4 and 8 wk after the start of quinagolide treatment. The quinagolide injections reduced milk yield and resulted in lower levels of κ-casein and α-lactalbumin mRNA in the mammary biopsies at wk 4 compared with the control cows. In the mammary tissue of the quinagolide-treated cows at wk 8 of treatment, cell proliferation (as determined by proliferating cell nuclear antigen labeling) was lower and apoptosis (as determined by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay) was higher than in the mammary tissue of the control cows. During differential milking, mammary epithelial cells (MEC) were extracted from the milk by centrifugation and purified by immunocytochemical binding to allow variations in the levels of mammary transcripts to be observed. After 9 wk of treatment, levels of α-lactalbumin and κ-casein mRNA were lower in the MEC isolated from milk of the quinagolide-treated cows. This effect was associated with lower PRL receptor mRNA levels and a tendency toward lower viability in the milk-isolated MEC from the 2×-milked glands. The decrease from 2× milking to 1× milking also downregulated α-lactalbumin and κ-casein transcripts in the milk-isolated MEC. Viability was higher for the MEC collected from the 1×-milked udder halves compared with the 2×-milked halves. In conclusion, the reduction in milk yield after chronic administration of the PRL-release inhibitor quinagolide is associated with a reduction in mammary cell activity, survival, and proliferation in lactating dairy cows. Reduced milking frequency was also associated with a decrease in MEC activity
Proton stopping in C+C, d+C, C+Ta and d+Ta collisions at 4.2A GeV/c
The shape of proton rapidity distributions is analysed in terms of their
Gaussian components, and the average rapidity loss is determined in order to
estimate the amount of stopping in C+C, d+C, C+Ta and d+Ta collisions at 4.2A
GeV/c. Three Gaussians correspond to the nuclear transparency and describe well
all peripheral and also C+C central collisions. Two-component shape is obtained
in case of d+C and C+Ta central collisions. Finally one Gaussian, found in d+Ta
central collisions, corresponds to the full stopping. The calculated values of
the average rapidity loss support the qualitative relationship between the
number of Gaussian components and the corresponding stopping power. It is also
observed, in central collisions, that the average rapidity loss increases with
the ratio of the number of target and the number of projectile participants.Comment: 9 pages REVTeX, 1 PS figure replaced, to be published in Phys.Rev.
Stratigraphy, age, and provenance of the Eocene Chumstick basin, Washington Cascades; implications for paleogeography, regional tectonics, and development of strike-slip basins: Reply
We welcome the comment by Evans (2022) and the opportunity to further discuss our study of the Chumstick Formation. The correlation of fault-bound nonmarine sedimentary units in central and western Washington has been a topic of interest, and debate, for many years (Frizzell, 1979; Taylor et al., 1988; Gresens et al., 1981; Gresens, 1983; Evans and Johnson, 1989; Evans, 1994; Cheney and Hayman, 2009). However, many questions about the regional correlation of these units were resolved with the publication of a suite of internally consistent high-precision 206Pb/238U zircon dates from volcanic interbeds throughout the early to middle Eocene stratigraphy (Eddy et al., 2016). This data set confirmed the timing of sediment deposition of the different members within the Chumstick Formation. Donaghy et al. (2021) provides a detailed study of the Chumstick Formation, which builds on earlier research by Gresens et al. (1981, 1983), McClincy (1986), and Evans (1994) by incorporating new geochronologic information and additional clast counts, detrital zircon geochronology, and facies mapping. We interpret large parts of the Chumstick Formation to represent a spatially and temporally distinct sedimentary system between the Leavenworth and Entiat fault zones that likely formed as a pull-apart basin. Evans (2022) objects to several of the interpretations presented in Donaghy et al. (2021) regarding the relationship between different members of the Chumstick Formation and surrounding sedimentary units, the timing of strike-slip faulting, and the regional tectonic setting of these rocks. We discuss each of these points in the following sections
First astronomical unit scale image of the GW Ori triple. Direct detection of a new stellar companion
Young and close multiple systems are unique laboratories to probe the initial
dynamical interactions between forming stellar systems and their dust and gas
environment. Their study is a key building block to understanding the high
frequency of main-sequence multiple systems. However, the number of detected
spectroscopic young multiple systems that allow dynamical studies is limited.
GW Orionis is one such system. It is one of the brightest young T Tauri stars
and is surrounded by a massive disk. Our goal is to probe the GW Orionis
multiplicity at angular scales at which we can spatially resolve the orbit. We
used the IOTA/IONIC3 interferometer to probe the environment of GW Orionis with
an astronomical unit resolution in 2003, 2004, and 2005. By measuring squared
visibilities and closure phases with a good UV coverage we carry out the first
image reconstruction of GW Ori from infrared long-baseline interferometry. We
obtain the first infrared image of a T Tauri multiple system with astronomical
unit resolution. We show that GW Orionis is a triple system, resolve for the
first time the previously known inner pair (separation 1.4 AU) and
reveal a new more distant component (GW Ori C) with a projected separation of
8 AU with direct evidence of motion. Furthermore, the nearly equal (2:1)
H-band flux ratio of the inner components suggests that either GW Ori B is
undergoing a preferential accretion event that increases its disk luminosity or
that the estimate of the masses has to be revisited in favour of a more equal
mass-ratio system that is seen at lower inclination. Accretion disk models of
GW Ori will need to be completely reconsidered because of this outer companion
C and the unexpected brightness of companion B.Comment: 5 pages, 9 figures, accepted Astronomy and Astrophysics Letters. 201
Epidemiology of nausea and vomiting of pregnancy: prevalence, severity, determinants, and the importance of race/ethnicity
<p>Abstract</p> <p>Background</p> <p>Studies that contributed to the epidemiology of nausea and vomiting of pregnancy have reported conflicting findings, and often failed to account for all possible co-variables necessary to evaluate the multidimensional associations. The objectives of this study were to: 1) Estimate the prevalence and the severity of nausea and vomiting of pregnancy during the 1<sup>st </sup>and the 2<sup>nd </sup>trimester of pregnancy, and 2) Identify determinants of presence and severity of nausea and vomiting of pregnancy during the 1<sup>st </sup>and 2<sup>nd </sup>trimesters separately, with a special emphasis on the impact of race/ethnicity.</p> <p>Methods</p> <p>A prospective study including pregnant women attending the Centre Hospitalier Universitaire (CHU) Sainte-Justine or René-Laennec clinics for their prenatal care was conducted from 2004 to 2006. Women were eligible if they were ≥ 18 years of age, and ≤ 16 weeks of gestation. Women were asked to fill out a 1<sup>st </sup>trimester self-administered questionnaire and were interviewed over the telephone during their 2<sup>nd </sup>trimester of pregnancy. Presence of nausea and vomiting of pregnancy was based on the reporting of pregnant women (yes/no); severity of symptoms was measured by the validated modified-PUQE index.</p> <p>Results</p> <p>Of the 367 women included in the study, 81.2% were Caucasians, 10.1% Blacks, 4.6% Hispanics, and 4.1% Asians. Multivariate analyses showed that race/ethnicity was significantly associated with a decreased likelihood of reporting nausea and vomiting of pregnancy (Asians vs. Caucasians OR: 0.13; 95%CI 0.02–0.73; and Blacks vs. Caucasians OR: 0.29; 95%CI 0.09–0.99).</p> <p>Conclusion</p> <p>Our study showed that race/ethnicity was associated with the reporting of nausea and vomiting of pregnancy in the 1<sup>st </sup>trimester of pregnancy.</p
Why Effective Medium Theory Fails in Granular Materials
Experimentally it is known that the bulk modulus, K, and shear modulus, \mu,
of a granular assembly of elastic spheres increase with pressure, p, faster
than the p^1/3 law predicted by effective medium theory (EMT) based on
Hertz-Mindlin contact forces. To understand the origin of these discrepancies,
we perform numerical simulations of granular aggregates under compression. We
show that EMT can describe the moduli pressure dependence if one includes the
increasing number of grain-grain contacts with p. Most important, the affine
assumption (which underlies EMT), is found to be valid for K(p) but breakdown
seriously for \mu(p). This explains why the experimental and numerical values
of \mu(p) are much smaller than the EMT predictions.Comment: 4 pages, 5 figures, http://polymer.bu.edu/~hmaks
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