284 research outputs found
Parametric study of manned life support systems. Volume 2 - Parametric relations and scaling law Final report, Jul. 1967- Aug. 1968
Parametric relations and scaling laws to describe manned life support system
Analysis of MERCATOR data Part I: variable B stars
We re-classified 31 variable B stars which were observed more than 50 times
in the Geneva photometric system with the P7 photometer attached to the
MERCATOR telescope (La Palma) during its first 3 years of scientific
observations. HD89688 is a possible beta Cephei/slowly pulsating B star hybrid
and the main mode of the COROT target HD180642 shows non-linear effects. The
Maia candidates are re-classified as either ellipsoidal variables or spotted
stars. Although the mode identification is still ongoing, all the
well-identified modes so far have a degree l = 0, 1 or 2.Comment: 4 pages, 3 figures. To appear in: Proceedings of JENAM 2005 'Distant
worlds', Communications in Asteroseismolog
Effect of the Premature Infant Oral Motor Intervention on Sucking Capacity in Preterm Infants in Turkey: A Randomized Controlled Trial
Background: Preterm infants have oral feeding difficulty that often delays discharge, indicating a need for evidence-based interventions for oral-motor development. Purpose: To test the Premature Infant Oral Motor Intervention (PIOMI) on the development of oral-motor function, feeding, and anthropometric outcomes using sucking manometry. Methods: A single-blind randomized experimental design was conducted with a sample of 60 preterm infants from 2 neonatal intensive care units between May 2019 and March 2020. The experimental group received PIOMI for 5 min/d for 14 consecutive days. Sucking capacity, anthropometrics (weight and head circumference), bottle feeding, breast/chest feeding initiation, and length of hospital stay were measured. The Yakut Sucking Manometer (PCT/TR2019/050678) was developed specifically for this study and tested for the first time. Results: The experimental group had a statistically significant percent increase over controls in sucking power (69%), continuous sucking before releasing the bottle (16%), sucking time (13%), and sucking amount (12%) with partial η2values of interaction between the groups of 0.692, 0.164, 0.136, and 0.121, respectively. The experimental group had a higher increase in weight (89%) and head circumference (81%) over controls (F = 485.130, P <.001; F = 254.754, P <.001, respectively). The experimental group transitioned to oral feeding 9.9 days earlier than controls (t = -2.822; P =.007), started breast/chest feeding 10.8 days earlier (t = 3.016; P =.004), and were discharged 3.0 days earlier. Implications for Research/Practice: The PIOMI had a significant positive effect on anthropometrics, sucking capacity, readiness to initiate bottle and breast/chest feeding, and a 3-day reduction in length of hospital stay. © 2022 Lippincott Williams and Wilkins. All rights reserved
Close binary stars in the solar-age Galactic open cluster M67
We present multi-colour time-series CCD photometry of the solar-age galactic
open cluster M67 (NGC 2682). About 3600 frames spread over 28 nights were
obtained with the 1.5 m Russian-Turkish and 1.2 m Mercator telescopes.
High-precision observations of the close binary stars AH Cnc, EV Cnc, ES Cnc,
the Scuti type systems EX Cnc and EW Cnc, and some long-period
variables belonging to M67 are presented. Three full multi-colour light curves
of the overcontact binary AH Cnc were obtained during three observing seasons.
Likewise we gathered three light curves of EV Cnc, an EB-type binary, and two
light curves of ES Cnc, a blue straggler binary. Parts of the light change of
long-term variables S1024, S1040, S1045, S1063, S1242, and S1264 are obtained.
Period variation analysis of AH Cnc, EV Cnc, and ES Cnc were done using all
times of mid-eclipse available in the literature and those obtained in this
study. In addition, we analyzed multi-colour light curves of the close binaries
and also determined new frequencies for the Scuti systems. The
physical parameters of the close binary stars were determined with simultaneous
solutions of multi-colour light and radial velocity curves. Finally we
determined the distance of M67 as 857(33) pc via binary star parameters, which
is consistent with an independent method from earlier studies.Comment: 12 pages, 9 Figures, 13 Table
Study of damage control systems for space station
Damage control systems for detecting and locating overboard and onboard leak and damage modes on space station
Dynamical evolution of active detached binaries on log Jo - log M diagram and contact binary formation
Orbital angular momentum (Jo), systemic mass (M) and orbital period (P)
distributions of chromospherically active binaries (CAB) and W Ursae Majoris (W
UMa) systems were investigated. The diagrams of log Jo - log P, log M - log P
and log Jo-log M were formed from 119 CAB and 102 W UMa stars. The log Jo-log M
diagram is found to be most meaningful in demonstrating dynamical evolution of
binary star orbits. A slightly curved borderline (contact border) separating
the detached and the contact systems was discovered on the log Jo - log M
diagram. Since orbital size (a) and period (P) of binaries are determined by
their current Jo, M and mass ratio q, the rates of orbital angular momentum
loss (dlog Jo/dt) and mass loss (dlog M/dt) are primary parameters to determine
the direction and the speed of the dynamical evolution. A detached system
becomes a contact system if its own dynamical evolution enables it to pass the
contact border on the log Jo - log M diagram. Evolution of q for a mass loosing
detached system is unknown unless mass loss rate for each component is known.
Assuming q is constant in the first approximation and using the mean decreasing
rates of Jo and M from the kinematical ages of CAB stars, it has been predicted
that 11, 23 and 39 cent of current CAB stars would transform to W UMa systems
if their nuclear evolution permits them to live 2, 4 and 6 Gyrs respectively.Comment: 28 pages, including 6 figures and 2 tables, accepted for publication
in MNRA
Absolute properties of the binary system BB Pegasi
We present a ground based photometry of the low-temperature contact binary BB
Peg. We collected all times of mid-eclipses available in literature and
combined them with those obtained in this study. Analyses of the data indicate
a period increase of 3.0(1) x 10^{-8} days/yr. This period increase of BB Peg
can be interpreted in terms of the mass transfer 2.4 x 10^{-8} Ms yr^{-1} from
the less massive to the more massive component. The physical parameters have
been determined as Mc = 1.42 Ms, Mh = 0.53 Ms, Rc = 1.29 Rs, Rh = 0.83 Rs, Lc =
1.86 Ls, and Lh = 0.94 Ls through simultaneous solution of light and of the
radial velocity curves. The orbital parameters of the third body, that orbits
the contact system in an eccentric orbit, were obtained from the period
variation analysis. The system is compared to the similar binaries in the
Hertzsprung-Russell and Mass-Radius diagram.Comment: 17 pages, 3 figures, accepted for Astronomical Journa
Effect of heat treatment on the wear and corrosion behaviors of a gray cast iron coated with a COLMONOY 88 alloy deposited by high velocity oxygen fuel (HVOF) thermal spray
The present work has been conducted in order to determine the influence of heat treatment on the wear and corrosion behaviours of a gray cast iron substrate coated with a Ni base coating deposited by HVOF thermal spray. The wear resistance of the coatings was obtained using a reciprocating wear tester by rubbing a 10 mm diameter steel ball on the coatings at normal atmospheric conditions. Corrosion tests were performed using potentiodynamic polarization measurements in a 3,5 % NaCl solution. It was observed that the corrosion and wear resistance of the coatings increased along with the reduction of porosity and roughness by the heat treatment
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