7,063 research outputs found
PONDER - A Real time software backend for pulsar and IPS observations at the Ooty Radio Telescope
This paper describes a new real-time versatile backend, the Pulsar Ooty Radio
Telescope New Digital Efficient Receiver (PONDER), which has been designed to
operate along with the legacy analog system of the Ooty Radio Telescope (ORT).
PONDER makes use of the current state of the art computing hardware, a
Graphical Processing Unit (GPU) and sufficiently large disk storage to support
high time resolution real-time data of pulsar observations, obtained by
coherent dedispersion over a bandpass of 16 MHz. Four different modes for
pulsar observations are implemented in PONDER to provide standard reduced data
products, such as time-stamped integrated profiles and dedispersed time series,
allowing faster avenues to scientific results for a variety of pulsar studies.
Additionally, PONDER also supports general modes of interplanetary
scintillation (IPS) measurements and very long baseline interferometry data
recording. The IPS mode yields a single polarisation correlated time series of
solar wind scintillation over a bandwidth of about four times larger (16 MHz)
than that of the legacy system as well as its fluctuation spectrum with high
temporal and frequency resolutions. The key point is that all the above modes
operate in real time. This paper presents the design aspects of PONDER and
outlines the design methodology for future similar backends. It also explains
the principal operations of PONDER, illustrates its capabilities for a variety
of pulsar and IPS observations and demonstrates its usefulness for a variety of
astrophysical studies using the high sensitivity of the ORT.Comment: 25 pages, 14 figures, Accepted by Experimental Astronom
Method of producing water-soluble glucuronic acid derivatives of vitamin A
Water soluble glucuronic acid derivatives of vitamin A, including retinoyl β-glucuronide and retinyl β-glucuronide, having in vivo activity comparable to retinoicacid and retinol and methods of their preparation are disclosed
Implications of sterile neutrinos for medium/long-baseline neutrino experiments and the determination of
We revisit some of the recent neutrino observations and anomalies in the
context of sterile neutrinos. Based on a general parametrization motivated in
the presence of sterile neutrinos, the consistency of the MINOS disappearance
data with additional sterile neutrinos is discussed. We also explore the
implications of sterile neutrinos for the measurement of in this
case. Regarding the determination of , we observe that the existence
of sterile neutrinos may induce a significant modification of the
angle in neutrino appearance experiments like T2K and MINOS, over and above the
ambiguities and degeneracies that are already present in 3-neutrino parameter
extractions. The modification is less significant in reactor neutrino
experiments like Double-CHOOZ, Daya Bay and RENO and therefore the extracted
value when sterile neutrinos are present is close to the one that
would be obtained in the 3-neutrino case. We also conclude that the results
from T2K imply a 90% C.L. lower-bound on , in the "" neutrino
case, which is still within the sensitivity of future reactor neutrino
experiments like Daya Bay, and consistent with the one- range of
recently reported by the Double-CHOOZ experiment. Finally,
we argue that for the recently determined best-fit parameters, the results in
the "" scenario would be very close to the medium/long baseline results
obtained in the "" case analyzed in this work.Comment: 25 pages, 9 figures, revtex4-1. Typos corrected, published versio
Optimality Theory as a Framework for Lexical Acquisition
This paper re-investigates a lexical acquisition system initially developed
for French.We show that, interestingly, the architecture of the system
reproduces and implements the main components of Optimality Theory. However, we
formulate the hypothesis that some of its limitations are mainly due to a poor
representation of the constraints used. Finally, we show how a better
representation of the constraints used would yield better results
Retinoic acid glucuronide preparations for application to the skin
A method and preparation are described for treating human skin with retinoic acid glucuronide (RAG) in a topical carrier. For treatment of acne or wrinkled skin, RAG can be applied in an effective amount which is nonirritating to the skin. Retinoid dermatitis, an objectionable side effect of topical application of retinoid compounds, can thereby be avoided
Big Data and MapReduce Challenges, Opportunities and Trends
Nowadays we all are surrounded by Big data. The term ‘Big Data’ itself indicates huge volume, high velocity, variety and veracity i.e. uncertainty of data which gave rise to new difficulties and challenges. Big data generated may be structured data, Semi Structured data or unstructured data. For existing database and systems lot of difficulties are there to process, analyze, store and manage such a Big Data. The Big Data challenges are Protection, Curation, Capture, Analysis, Searching, Visualization, Storage, Transfer and sharing. Map Reduce is a framework using which we can write applications to process huge amount of data, in parallel, on large clusters of commodity hardware in a reliable manner. Lot of efforts have been put by different researchers to make it simple, easy, effective and efficient. In our survey paper we emphasized on the working of Map Reduce, challenges, opportunities and recent trends so that researchers can think on further improvement
Non-teratogenic vitamin A preparation for women of child-bearing age
For treatment of acne the glucuronide of retinoic acid (retinoyl β-glucuronide) is orally administered to women of child-bearing age who are capable of conception. This therapy is safer than the oral administration of retinoic acid because retinoic acid glucuronide is essentially non-teratogenic at dose levels effective for the acne treatment. The retinoic acid glucuronide can be in all-trans or 13-cis form
Simple Pendulum Revisited
We describe a 8085 microprocessor interface developed to make reliable time
period measurements. The time period of each oscillation of a simple pendulum
was measured using this interface. The variation of the time period with
increasing oscillation was studied for the simple harmonic motion (SHM) and for
large angle initial displacements (non-SHM). The results underlines the
importance of the precautions which the students are asked to take while
performing the pendulum experiment.Comment: 17 pages with 10 figure
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