6,968 research outputs found
The suitability of various spacecraft for future space applications missions
The Space Applications Advisory Committee (SAAC) of NASA's Advisory Council was asked by the Associate Administrator for Space Science and Applications to consider the most suitable future means for accomplishing space application missions. To comply with this request, SAAC formed a Task Force whose report is contained in this document. In their considerations, the Task Force looked into the suitability of likely future spacecraft options for supporting various types of application mission payloads. These options encompass a permanent manned space station, the Space Shuttle operating in a sortie mode, unmanned platforms that integrate a wide variety of instruments or other devices, and smaller free fliers that accommodate at most a few functions. The Task Force also recognized that the various elements could be combined to form a larger space infrastructure. This report summarizes the results obtained by the Task Force. It describes the approach utilized, the findings and their analysis, and the conclusions
Coping Ability of Medical and Nursing Students: A Cause of Concern
Background: Medical students today are subject to a variety of stress; academic, social, emotional or stress in the form of affliction of health during their stay at medical school. The physiological response to these depends on various factors including their inherent coping abilities. This study was designed to examine the coping ability of medical and nursing students at the time of admission to medical school. Materials and Methods: 42 medical and 34 nursing students volunteered for the study. They were administered the BAI questionnaire and classified as good and poor adjusters based on their score. Results: The study revealed an unsatisfactory overall coping ability to be prevalent among medical and nursing students. Conclusion: This study showed that there is a need for orientation and counselling of medical and nursing students at the start of college
Measurements of Static and Total Pressure Throughout the Transonic Speed Range as Obtained from an Airspeed Head Mounted on a Freely Falling Body
No abstract availabl
DCO, DCN and ND reveal three different deuteration regimes in the disk around the Herbig Ae star HD163296
The formation pathways of deuterated species trace different regions of
protoplanetary disks and may shed light into their physical structure. We aim
to constrain the radial extent of main deuterated species; we are particularly
interested in spatially characterizing the high and low temperature pathways
for enhancing deuteration of these species. We observed the disk surrounding
the Herbig Ae star HD 163296 using ALMA in Band 6 and obtained resolved
spectral imaging data of DCO (=3-2), DCN (=3-2) and ND
(=3-2). We model the radial emission profiles of DCO, DCN and
ND, assuming their emission is optically thin, using a parametric model
of their abundances and radial excitation temperature estimates. DCO can be
described by a three-region model, with constant-abundance rings centered at 70
AU, 150 AU and 260 AU. The DCN radial profile peaks at about ~60 AU and
ND is seen in a ring at ~160 AU. Simple models of both molecules using
constant abundances reproduce the data. Assuming reasonable average excitation
temperatures for the whole disk, their disk-averaged column densities (and
deuterium fractionation ratios) are 1.6-2.6 cm
(0.04-0.07), 2.9-5.2 cm (0.02) and 1.6-2.5 cm (0.34-0.45) for DCO, DCN and ND, respectively.
Our simple best-fit models show a correlation between the radial location of
the first two rings in DCO and the DCN and ND abundance
distributions that can be interpreted as the high and low temperature
deuteration pathways regimes. The origin of the third DCO ring at 260 AU is
unknown but may be due to a local decrease of ultraviolet opacity allowing the
photodesorption of CO or due to thermal desorption of CO as a consequence of
radial drift and settlement of dust grains
Harvest index of lupins, Low tillering cereals and Maturity by sowing date in cereals.
Trial 87GE21
Effect of plant density on branching, pod setting and yield development of lupins.
Location: Geraldton
To determine the influence of plant density and between-plant variability in vegetative growth on the branching, pod setting and yield development of lupins
Trial 87GE9
Chemicals to control vegetative growth and improve pod set in lupins.
Location: West Binnu
To examine the effect of a number of growth regulating chemicals on the branching, pod setting and yield of lupins under conditions favoring high biomass production.
Trial 87GE19
Chemicals to control vegetative growth and improve pod set in lupins.
Location: Nabawa
To examine the effect of a number of growth regulating chemicals on the branching, pod setting and yield of lupins under conditions favouring high biomass production.
Trial 87GE72
Effect of plant density on growth and yield of lupins.
Location: South Yuna
To determine the influence of plant density on the growth, branching, pod setting and yield development of branching and reduced branching lupins under conditions producing different levels of biomass
Trial 87E34
Effect of sowing time on yield of lupin varieties.
Location: Esperance Downs Research Station.
Lupins are well adapted to the cooler, long-season environments of the southern coastal sandplain. of Western Australia. This trial aims to help establish varietal characteristics required to produce high-yielding lupin crops in the cool, long-season environment of southern Australia. The specific aim is to determine the influence of sowing date on the growth and yield of lupin varieties differing in maturity and branching habit in the south-coast environment.
LVT Sampling - 1986 and 1987 seasons - Effect of genotype and environment on growth, yield components, harvest index and yield of lupins.
Low harvest index (H.I.) is often suggested as the cause of poor lupin seed yields, and it is argued that all vegetative lupin crops have inherently poor pod set and low harvest index. By sampling LVT\u27s across a wide range of sites in 1986 and selected sites in 1987, we aimed to determine the effect of environment on lupin growth, branching, seed yield, H.I. and yield components. Sampling of two branching genotypes and a reduced branching line would permit the assessment of genotypic effects and any G x E interactions.
Trial 87C66
Effect of maturity and sowing date on wheat and barley.
Location Chapman Research Stations
Two similar trials at North Mullewa and East Chapman were not harvested due to severe drought and high weed populations, respectively. Dr J. Hamblin\u27s summary reports the results of three further sowing date trials
Exploring DCO as a tracer of thermal inversion in the disk around the Herbig Ae star HD163296
We aim to reproduce the DCO emission in the disk around HD163296 using a
simple 2D chemical model for the formation of DCO through the cold
deuteration channel and a parametric treatment of the warm deuteration channel.
We use data from ALMA in band 6 to obtain a resolved spectral imaging data cube
of the DCO =3--2 line in HD163296 with a synthesized beam of
0."53 0."42. We adopt a physical structure of the disk from the
literature that reproduces the spectral energy distribution. We then apply a
simplified chemical network for the formation of DCO that uses the physical
structure of the disk as parameters along with a CO abundance profile, a
constant HD abundance and a constant ionization rate. Finally, from the
resulting DCO abundances, we calculate the non-LTE emission using the 3D
radiative transfer code LIME. The observed DCO emission is reproduced by a
model with cold deuteration producing abundances up to .
Warm deuteration, at a constant abundance of , becomes
fully effective below 32 K and tapers off at higher temperatures, reproducing
the lack of DCO inside 90 AU. Throughout the DCO emitting zone a CO
abundance of is found, with 99\% of it frozen out below
19 K. At radii where both cold and warm deuteration are active, warm
deuteration contributes up to 20\% of DCO, consistent with detailed
chemical models. The decrease of DCO at large radii is attributed to a
temperature inversion at 250 AU, which raises temperatures above values where
cold deuteration operates. Increased photodesorption may also limit the radial
extent of DCO. The corresponding return of the DCO layer to the
midplane, together with a radially increasing ionization fraction, reproduces
the local DCO emission maximum at 260 AU.Comment: 9 pages, 5 figures, accepted 7th July 201
Coherent States for the Non-Linear Harmonic Oscillator
Wave packets for the Quantum Non-Linear Oscillator are considered in the
Generalized Coherent State framerwork. To first order in the non-linearity
parameter the Coherent State behaves very similarly to its classical
counterpart. The position expectation value oscillates in a simple harmonic
manner. The energy-momentum uncertainty relation is time independent as in a
harmonic oscillator. Various features, (such as the Squeezed State nature), of
the Coherent State have been discussed
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