3,789 research outputs found
Some Novel Applications of Explanation-Based Learning to Parsing Lexicalized Tree-Adjoining Grammars
In this paper we present some novel applications of Explanation-Based
Learning (EBL) technique to parsing Lexicalized Tree-Adjoining grammars. The
novel aspects are (a) immediate generalization of parses in the training set,
(b) generalization over recursive structures and (c) representation of
generalized parses as Finite State Transducers. A highly impoverished parser
called a ``stapler'' has also been introduced. We present experimental results
using EBL for different corpora and architectures to show the effectiveness of
our approach.Comment: uuencoded postscript fil
Disambiguation of Super Parts of Speech (or Supertags): Almost Parsing
In a lexicalized grammar formalism such as Lexicalized Tree-Adjoining Grammar
(LTAG), each lexical item is associated with at least one elementary structure
(supertag) that localizes syntactic and semantic dependencies. Thus a parser
for a lexicalized grammar must search a large set of supertags to choose the
right ones to combine for the parse of the sentence. We present techniques for
disambiguating supertags using local information such as lexical preference and
local lexical dependencies. The similarity between LTAG and Dependency grammars
is exploited in the dependency model of supertag disambiguation. The
performance results for various models of supertag disambiguation such as
unigram, trigram and dependency-based models are presented.Comment: ps file. 8 page
Ant Species Richness Around Amravati City Maharashtra, India
Ants deserve a special place in the study of ecology, including behavior, given their species richness, social habits, and high densities, contributing to much of the animal biomes on earth (Gadagkar et.at. 1993). As ants can be studied virtually everywhere from forest interiors below ground, right up to the kitchen, we attempted a study to assess the ant species richness in a variety of habitats in and around Amravati city. The prime objective of this study is to prepare a partial checklist of ants of Amravati and to compare species richness between selected study sites. Eight study sites with different levels and types of vegetation were selected for the study.
We employed an “all out search” method for collection in the months of June and July 2010. Ants were hand collected using a brush and forecep during the day time for 6 hrs at each study site. Collected samples were preserved in 70% alcohol in the Department of Zoology, Govt. Vidarbha Institute of Science & Humanities, Amravati.
We identified Ants up to the genus level by using a Stemi DV4 Stereo microscope based on taxonomic keys of (Holldobles & Wilson, 1990; Bolton, 1994; Mathew & R.N. Tiwari, 2000).
During the present study a total of 34 species of 20 genera have been recognized from Amravati city representing five subfamilies namely Myrmicinae, Formicinae, Ponerinae, Dolichoderinae and Pseudomyrmicinae. Out of this subfamily, Myrmicinae is the most abundant having 11 genera including the genus Rhoptromyrmex. It has been recorded for the first time in this region, followed by Formicinae with four genera for being recorded for the first time as genus Oecophylla. Subfamily Ponerinae and Dolichoderinae were recorded only with two genera each; while the subfamily Pseudomyrmicinae where recorded very poorly with only one genera from G.V.I.S.H. campus.
Few ant genera such as Crematogaster and Myrmicaria of subfamily Myrmicinae, Camponotus and Polyrhachis of subfamily Formicinae and Leptogenys of subfamily Ponerinae were mostly found in all the habitats and most localities. Few genera are confined to few localities or habitat types, such as Rhoptromyrmex and Oecophylla recorded only from Pohara forests. Genus Tetraponera of subfamily Pseudomyrmicinae were collected from the tree trunk of Azadirakhta indica in the G.V.I.S.H. campus. 
Comparison of ant species distribution between the different study sites revealed that ant species richness was highest in Pohara forest with 28 species & lowest with 9 species around urban areas. Relatively high ant species richness was recorded at all the study sites such as the Agriculture field, Tree plantation area, and the Wadali and Chhatri Garden. On the other hand, ant species richness was low around urban houses compared to rural houses due to little or no vegetation and high levels of disturbance. The tree plantation site, roads, and pavement showed higher numbers of ant species compared to around urban areas probably due to road side richness of tree plantation.
From this study we conclude that due to availability of food and shelter, richness of ant species increases in forest and tree plantation areas. The number of ant species declines in low vegetative areas including urban areas. It is possible to study the ecology and biodiversity of living faunas by the studying the habitats of ants. The environs of Amravati city are rich in Ant fauna which deserve further study
Allelic Frequency of ABO And Rh D Blood Group Among The Banjara Backward Caste of Yavatmal District, Maharashtra , India
The distribution of ABO blood groups and Rh(D) factor has been studied among the Banjara of Backward population of Yavatmal (Maharashtra). The A, B, O and AB blood group percentage were recorded as 24.54%, 33.82%, 29.64% and 12% respectively. The allele frequencies of O, A, B and AB groups in the combined data were found to be 0.5354, 0.2022 and 0.2624 respectively. The distribution of Rh(D) group varies among the ABO blood groups. The Rh(D) positive allelic frequency was 0.8405 and the Rh(D) negative incidence was recorded as 02.55% in the studied population
Probing the Dark Ages at Z~20: The SCI-HI 21 cm All-Sky Spectrum Experiment
We present first results from the SCI-HI experiment, which we used to measure
the all-sky-averaged \cm brightness temperature in the redshift range
14.8<z<22.7. The instrument consists of a single broadband sub-wavelength size
antenna and a sampling system for real-time data processing and recording.
Preliminary observations were completed in June 2013 at Isla Guadalupe, a
Mexican biosphere reserve located in the Pacific Ocean. The data was cleaned to
excise channels contaminated by radio frequency interference (RFI), and the
system response was calibrated by comparing the measured brightness temperature
to the Global Sky Model of the Galaxy and by independent measurement of Johnson
noise from a calibration terminator. We present our results, discuss the
cosmological implications, and describe plans for future work.Comment: 5 pages, 5 figures, accepted for publication in ApJ Letter
Viable entanglement detection of unknown mixed states in low dimensions
We explore procedures to detect entanglement of unknown mixed states, which
can be experimentally viable. The heart of the method is a hierarchy of simple
feasibility problems, which provides sufficient conditions to entanglement. Our
numerical investigations indicate that the entanglement is detected with a cost
which is much lower than full state tomography. The procedure is applicable to
both free and bound entanglement, and involves only single copy measurements.Comment: 8 pages, 9 figures, 4 table
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