21,438 research outputs found
Human operator identification model and related computer programs
Four computer programs which provide computational assistance in the analysis of man/machine systems are reported. The programs are: (1) Modified Transfer Function Program (TF); (2) Time Varying Response Program (TVSR); (3) Optimal Simulation Program (TVOPT); and (4) Linear Identification Program (SCIDNT). The TV program converts the time domain state variable system representative to frequency domain transfer function system representation. The TVSR program computes time histories of the input/output responses of the human operator model. The TVOPT program is an optimal simulation program and is similar to TVSR in that it produces time histories of system states associated with an operator in the loop system. The differences between the two programs are presented. The SCIDNT program is an open loop identification code which operates on the simulated data from TVOPT (or TVSR) or real operator data from motion simulators
Portable, high intensity isotopic neutron source provides increased experimental accuracy
Small portable, high intensity isotopic neutron source combines twelve curium-americium beryllium sources. This high intensity of neutrons, with a flux which slowly decreases at a known rate, provides for increased experimental accuracy
Direct determination of photodisintegration cross sections and the p-process
Photon-induced reactions play a key role in the nucleosynthesis of heavy
neutron-deficient nuclei, the so-called p-nuclei. In this paper we review the
present status of experiments on photon-induced reactions at energies of
astrophysical importance and their relevance to p-process modeling.Comment: Nucl. Phys. A, in pres
CosmoDM and its application to Pan-STARRS data
The Cosmology Data Management system (CosmoDM) is an automated and flexible
data management system for the processing and calibration of data from optical
photometric surveys. It is designed to run on supercomputers and to minimize
disk I/O to enable scaling to very high throughput during periods of
reprocessing. It serves as an early prototype for one element of the
ground-based processing required by the Euclid mission and will also be
employed in the preparation of ground based data needed in the eROSITA X-ray
all sky survey mission. CosmoDM consists of two main pipelines. The first is
the single-epoch or detrending pipeline, which is used to carry out the
photometric and astrometric calibration of raw exposures. The second is the co-
addition pipeline, which combines the data from individual exposures into
deeper coadd images and science ready catalogs. A novel feature of CosmoDM is
that it uses a modified stack of As- tromatic software which can read and write
tile compressed images. Since 2011, CosmoDM has been used to process data from
the DECam, the CFHT MegaCam and the Pan-STARRS cameras. In this paper we shall
describe how processed Pan-STARRS data from CosmoDM has been used to optically
confirm and measure photometric redshifts of Planck-based Sunyaev-Zeldovich
effect selected cluster candidates.Comment: 11 pages, 4 figures. Proceedings of Precision Astronomy with Fully
Depleted CCDs Workshop (2014). Accepted for publication in JINS
iCrawl: Improving the Freshness of Web Collections by Integrating Social Web and Focused Web Crawling
Researchers in the Digital Humanities and journalists need to monitor,
collect and analyze fresh online content regarding current events such as the
Ebola outbreak or the Ukraine crisis on demand. However, existing focused
crawling approaches only consider topical aspects while ignoring temporal
aspects and therefore cannot achieve thematically coherent and fresh Web
collections. Especially Social Media provide a rich source of fresh content,
which is not used by state-of-the-art focused crawlers. In this paper we
address the issues of enabling the collection of fresh and relevant Web and
Social Web content for a topic of interest through seamless integration of Web
and Social Media in a novel integrated focused crawler. The crawler collects
Web and Social Media content in a single system and exploits the stream of
fresh Social Media content for guiding the crawler.Comment: Published in the Proceedings of the 15th ACM/IEEE-CS Joint Conference
on Digital Libraries 201
Using x ray images to detect substructure in a sample of 40 Abell clusters
Using a method for constraining the dynamical state of a galaxy cluster by examining the moments of its x-ray surface brightness distribution, we determine the statistics of cluster substructure for a sample of 40 Abell clusters. Using x-ray observations from the Einstein Observatory Imaging Proportional Counter (IPC), we measure the first moment M1(r), the ellipsoidal orientation angle theta2(r), and the axial ratio eta(r) at several different radii in the cluster. We determine the effects of systematics such as x-ray point source emission, telescope vignetting, Poisson noise, and characteristics of the IPC by measuring the same parameters on an ensemble of simulated cluster images. Due to the small band-pass of the IPC, the ICM emissivity is nearly independent of temperature so the intensity at each point in the IPC images is simply proportional to the emission measure calculated along the line of sight through the cluster (e.g. Fabricant et al. 1980). Therefore, barring a change superposition of two x-ray emitting clusters, a significant variation in the image centroid M1(r) as a function of radius indicates that the center of mass of the intra-cluster medium (ICM) varies with radius. We argue that such a configuration (essentially an m = 1 component in the ICM density distribution) is a non-equilibrium component; it results from an off-center subclump or a recent merger in the ICM
Visual adaptation to thin and fat bodies transfers across identity
Visual perception is highly variable and can be influenced by the surrounding world. Previous research has revealed that body perception can be biased due to adaptation to thin or fat body shapes. The aim of the present study was to show that adaptation to certain body shapes and the resulting perceptual biases transfer across different identities of adaptation and test stimuli. We designed two similar adaptation experiments in which healthy female participants adapted to pictures of either thin or fat bodies and subsequently compared more or less distorted pictures of their own body to their actual body shape. In the first experiment (n = 16) the same identity was used as adaptation and test stimuli (i.e. pictures of the participant’s own body) while in the second experiment (n = 16) we used pictures of unfamiliar thin or fat bodies as adaptation stimuli. We found comparable adaptation effects in both experiments: After adaptation to a thin body, participants rated a thinner than actual body picture to be the most realistic and vice versa. We therefore assume that adaptation to certain body shapes transfers across different identities. These results raise the questions of whether some type of natural adaptation occurs in everyday life. Natural and predominant exposure to certain bodily features like body shape – especially the thin ideal in Western societies – could bias perception for these features. In this regard, further research might shed light on aspects of body dissatisfaction and the development of body image disturbances in terms of eating disorders
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