3,407 research outputs found
Development of a facility using robotics for testing automation of inertial instruments
The Integrated Robotics System Simulation (ROBSIM) was used to evaluate the performance of the PUMA 560 arm as applied to testing of inertial sensors. Results of this effort were used in the design and development of a feasibility test environment using a PUMA 560 arm. The implemented facility demonstrated the ability to perform conventional static inertial instrument tests (rotation and tumble). The facility included an efficient data acquisitions capability along with a precision test servomechanism function resulting in various data presentations which are included in the paper. Analysis of inertial instrument testing accuracy, repeatability and noise characteristics are provided for the PUMA 560 as well as for other possible commercial arm configurations. Another integral aspect of the effort was an in-depth economic analysis and comparison of robot arm testing versus use of contemporary precision test equipment
Adaptive Energy Efficient Scheduling (AEES) for Fault Tolerant Coverage in Sensor Networks
For many sensor network applications it is necessary to provide full sensing coverage to a security-sensitive area. To actively monitor the set of target the subset of sensors are redundantly deployed. One of the major challenges in devising such network lies in the constrained energy and to tolerate unexpected failure to prolong the life span of the network. In this we rapidly restore the field monitoring, by periodically refreshing and switching the cover to tackle unanticipated failure in an energy efficient manner, because energy is the most critical resource considering the irreplaceable of batteries of the sensor nodes. In the same time it should amenably support more than one sensor at a time with different degree in distributed approach that periodically selects the covers and switch between them to extend coverage time and tolerate unexpected failures at runtime. In this scheme the sensor is an autonomous system that has the authority to decide how to cover its sensing range. It also incorporates a novel technique for offline cover update (OCU) to facilitate asynchronous transition between covers. This approach is robust to failure pattern is no uniform.
DOI: 10.17762/ijritcc2321-8169.15013
Nutrient accounting in global food systems
Working across agriculture–nutrition domains, nutrition balance sheets provide farm-to-fork estimates of the availability of dietary nutrients for human consumption
Far-infrared observations of young clusters embedded in the R Coronae Austrinae and RHO Ophiuchi dark clouds
Multicolor far infrared maps in two nearby dark clouds, R Coronae Austrinae and rho Ophiuchi, were made in order to investigate the individual contribution of low mass stars to the energetics and dynamics of the surrounding gas and dust. Emission from cool dust associated with five low mass stars in Cr A and four in rho Oph was detected; their far infrared luminosities range from 2 far infrared luminosities L. up to 40 far infrared luminosities. When an estimate of the bolometric luminosity was possible, it was found that typically more than 50% of the star's energy was radiated longward of 20 micrometers. meaningful limits to the far infrared luminosities of an additional eleven association members in Cr A and two in rho Oph were also obtained. The dust optical depth surrounding the star R Cr A appears to be asymmetric and may control the dynamics of the surrounding molecular gas. The implications of the results for the cloud energetics and star formation efficiency in these two clouds are discussed
Estimation of light lamb carcass composition by in vivo real-time ultrasonography at four anatomical locations
The objectives of this study were to
study the relationship between in vivo ultrasound measurements
and cold carcass measurements at 4 anatomical
points of the backbone, and to establish regression
equations to estimate carcass composition within
the cold carcass weight range for Ternasco lambs (8
to 12.5 kg) by using ultrasonic measurements taken at
a single location. Measurements of subcutaneous fat
and skin thickness and of muscle depth and width were
taken over the 10th to 11th and 12th to 13th thoracic
vertebrae and the 1st to 2nd and 3rd to 4th lumbar
vertebrae. These measurements were taken at 2 and
4 cm from the nearest end of the LM to the backbone
and at 1/3 of the LM width with the probe perpendicular
to and parallel to the backbone. The left sides
of the carcasses were dissected into muscle, fat, and
bone. Body weight (22.6 kg) and cold carcass weight
(10.8 kg) were representative of Ternasco light lambs.
Muscle depth measured at 2 cm, 4 cm, and 1/3 of LM
width remained regular, with slight ups and downs
along the spine. All the pairs of in vivo ultrasound and
cold carcass measurements were significantly different
(P < 0.05) and had small correlations. All the ultrasound
measurements of muscle depth at any location
or at any distance to the backbone were less than their
equivalent cold carcass measurements, with differences
ranging from 0.8 to 5.9 mm. Differences between ultrasound
fat thickness + interface (US_FDGI) and cold
carcass fat thickness were less than differences between
ultrasound fat thickness and cold carcass fat thickness,
ranging from −0.9 to −1.0 mm for the former and from
−2.1 to −0.5 mm for the latter. The small differences in
absolute values between US_FDGI and cold carcass fat
thickness suggest that US_FDGI is the best measure
of the real fatness level of the lambs. The best prediction
equations for muscle, bone, and fat were developed
with in vivo ultrasound data measured at the 1st to
2nd lumbar vertebrae perpendicularly to the backbone,
but they had limited predictive value. To predict the
muscle content of carcass, BW and muscle depth were
included, and they explained 59% of variation. Fiftyone
percent of total fat was predicted by BW and fat
thickness, whereas only 17% of the variation in bone
was predicted by 2 fat-related variables. The BW of
lambs was an important predictor to improve regression
equations but ultrasound measurements were the
most important variables when a narrow range of BW
was used
Evolution of embryonic developmental period in the marine bird families Alcidae and Spheniscidae: roles for nutrition and predation?
Background: Nutrition and predation have been considered two primary agents of selection important in theevolution of avian life history traits. The relative importance of these natural selective forces in the evolution of avianembryonic developmental period (EDP) remain poorly resolved, perhaps in part because research has tended to focuson a single, high taxonomic-level group of birds: Order Passeriformes. The marine bird families Alcidae (auks) andSpheniscidae (penguins) exhibit marked variation in EDP, as well as behavioural and ecological traits ultimately linkedto EDP. Therefore, auks and penguins provide a unique opportunity to assess the natural selective basis of variation in akey life-history trait at a low taxonomic-level. We used phylogenetic comparative methods to investigate the relativeimportance of behavioural and ecological factors related to nutrition and predation in the evolution of avian EDP.Results: Three behavioural and ecological variables related to nutrition and predation risk (i.e., clutch size, activitypattern, and nesting habits) were significant predictors of residual variation in auk and penguin EDP based on modelspredicting EDP from egg mass. Species with larger clutch sizes, diurnal activity patterns, and open nests hadsignificantly shorter EDPs. Further, EDP was found to be longer among birds which forage in distant offshore waters,relative to those that foraged in near shore waters, in line with our predictions, but not significantly so.Conclusion: Current debate has emphasized predation as the primary agent of selection driving avian life historydiversification. Our results suggest that both nutrition and predation have been important selective forces in theevolution of auk and penguin EDP, and highlight the importance of considering these questions at lower taxonomicscales. We suggest that further comparative studies on lower taxonomic-level groups will continue to constructivelyinform the debate on evolutionary determinants of avian EDP, as well as other life history parameters
Chandra Measurements of a Complete Sample of X-ray Luminous Galaxy Clusters: The Luminosity-Mass Relation
We present the results of work involving a statistically complete sample of
34 galaxy clusters, in the redshift range 0.15z0.3 observed with
. We investigate the luminosity-mass () relation for the cluster
sample, with the masses obtained via a full hydrostatic mass analysis. We
utilise a method to fully account for selection biases when modeling the
relation, and find that the relation is significantly different than the
relation modelled when not account for selection effects. We find that the
luminosity of our clusters is 2.20.4 times higher (when accounting for
selection effects) than the average for a given mass, its mass is 30% lower
than the population average for a given luminosity. Equivalently, using the
relation measured from this sample without correcting for selection biases
would lead to the underestimation by 40% of the average mass of a cluster with
a given luminosity. Comparing the hydrostatic masses to mass estimates
determined from the parameter, we find that they are entirely
consistent, irrespective of the dynamical state of the cluster.Comment: 31 pages, 43 figures, accepted for publication in MNRA
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