2,123 research outputs found
Giant dipole resonance with exact treatment of thermal fluctuations
The shape fluctuations due to thermal effects in the giant dipole resonance
(GDR) observables are calculated using the exact free energies evaluated at
fixed spin and temperature. The results obtained are compared with Landau
theory calculations done by parameterizing the free energy. The Landau theory
is found to be insufficient when the shell effects are dominating.Comment: 5 pages, 2 figure
Technical Efficiency in Agricultural Production and Its Determinants : An Exploratory Study at the District Level
Given the importance of agriculture to the well being of a large percentage of Indias population, it becomes important to study how improvements can be made in the productivity of this sector. This study attempts to estimate the technical efficiency a measure of how well inputs are being used towards producing output of about 250 Indian districts in 1990-91. It employs the stochastic frontier function methodology. The results indicate that (i) the land elasticity is the highest followed by fertilizer; (ii) the mean efficiency of raising agricultural output is 79 per cent and therefore there is a scope for increasing output by 21 per cent without additional resources; (iii) states such as Madhya Pradesh, Uttar Pradesh, and Rajasthan have the largest number of districts with below average TE and they stand to gain the most from policy interventions towards improving technical efficiency. The results further indicate that health, education, and infrastructure are powerful drivers of efficiency at the district level and the relative importance of the determinants of efficiency across districts depends greatly on environmental factors, such as agro-climatic zones, technological factors, and crop mix. The results highlight the need for developing policy strategies at a more localized level.agriculture, technical efficiency, stochastic frontier function, India
Combined spectral and spatial processing of ERTS imagery data
A procedure for extracting a set of textural features for ERTS-1 MSS data is presented. The textural features were combined with a set of spectral features and were used to develop a classification algorithm for identifying the land use categories of blocks of digital MSS data. The classification algorithm was derived from a training set of 314 blocks and tested on a set of 310 blocks. The overall accuracy of the classifier was found to be 83.5% on seven land use categories
Beyond Triangles: A Distributed Framework for Estimating 3-profiles of Large Graphs
We study the problem of approximating the -profile of a large graph.
-profiles are generalizations of triangle counts that specify the number of
times a small graph appears as an induced subgraph of a large graph. Our
algorithm uses the novel concept of -profile sparsifiers: sparse graphs that
can be used to approximate the full -profile counts for a given large graph.
Further, we study the problem of estimating local and ego -profiles, two
graph quantities that characterize the local neighborhood of each vertex of a
graph.
Our algorithm is distributed and operates as a vertex program over the
GraphLab PowerGraph framework. We introduce the concept of edge pivoting which
allows us to collect -hop information without maintaining an explicit
-hop neighborhood list at each vertex. This enables the computation of all
the local -profiles in parallel with minimal communication.
We test out implementation in several experiments scaling up to cores
on Amazon EC2. We find that our algorithm can estimate the -profile of a
graph in approximately the same time as triangle counting. For the harder
problem of ego -profiles, we introduce an algorithm that can estimate
profiles of hundreds of thousands of vertices in parallel, in the timescale of
minutes.Comment: To appear in part at KDD'1
Distributed Estimation of Graph 4-Profiles
We present a novel distributed algorithm for counting all four-node induced
subgraphs in a big graph. These counts, called the -profile, describe a
graph's connectivity properties and have found several uses ranging from
bioinformatics to spam detection. We also study the more complicated problem of
estimating the local -profiles centered at each vertex of the graph. The
local -profile embeds every vertex in an -dimensional space that
characterizes the local geometry of its neighborhood: vertices that connect
different clusters will have different local -profiles compared to those
that are only part of one dense cluster.
Our algorithm is a local, distributed message-passing scheme on the graph and
computes all the local -profiles in parallel. We rely on two novel
theoretical contributions: we show that local -profiles can be calculated
using compressed two-hop information and also establish novel concentration
results that show that graphs can be substantially sparsified and still retain
good approximation quality for the global -profile.
We empirically evaluate our algorithm using a distributed GraphLab
implementation that we scaled up to cores. We show that our algorithm can
compute global and local -profiles of graphs with millions of edges in a few
minutes, significantly improving upon the previous state of the art.Comment: To appear in part at WWW'1
Crop classification using airborne radar and LANDSAT data
Airborne radar data acquired with a 13.3 GHz scatterometer over a test-site near Colby, Kansas were used to investigate the statistical properties of the scattering coefficient of three types of vegetation cover and of bare soil. A statistical model for radar data was developed that incorporates signal-fading and natural within-field variabilities. Estimates of the within-field and between-field coefficients of variation were obtained for each cover-type and compared with similar quantities derived from LANDSAT images of the same fields. The classification accuracy provided by LANDSAT alone, radar alone, and both sensors combined was investigated. The results indicate that the addition of radar to LANDSAT improves the classification accuracy by about 10; percentage-points when the classification is performed on a pixel basis and by about 15 points when performed on a field-average basis
Lifestyle and Language in Thirumurugatrupadai
Tamil literature clearly reflects the lifestyle of the ancient Tamils. In the field of anthropology Tamil literature plays an important role. The richness of a country's language is judged by the richness of its literature in the regional language spoken by the people of that country. The ideas found in those literary works shapes the mind and lifestyle of both the present and future generation too. Thirumurugatrupadai which is one among the Pattuppattu (anthology) is about a person who is blessed by the lord Murugan, comforting another servant to Murugan. In this text author Nakkiranar has sung songs in six sections about the places where Murugan used to stay such as Tiruparanguntram, Tiruchendur, Palani, Swamimalai, Palamuthircholai and Kuntuthoradal. Thus, the article briefly explains about the Kurinji land people, their customs, how they worshipped lord Murugan, their clothing, accessories, the sense of solidarity with relatives, the spirit of living together, chastity, and the development of virtue. All these things strengthen the richness of the Tamil language
Economic viability of mechanized fishing units and socio-economics of fishing ban in Kerala
In open access unregulated marine fisheries, the viability of a fishing unit greatly influences the entry or exit of vessels in the
fishing industry. The economic performance of fishing operations is affected by various factors including fluctuations in
revenue, diminishing catch per unit of effort, unforeseen increases in the cost of key inputs and catch and effort restrictions.
Capital and labour will continue to enter the fishery until the economic rents are totally dissipated and profits to individual
units are reduced to the level of their opportunity costs. In the long run, the reduction in catch rates lead to reduction in
fishing effort levels. The economic performance also plays a crucial role in the investment decisions at micro level. The
paper analyses the viability of various mechanized fishing units in the Kerala state using different economic and financial
indicators. Socioeconomic impact of fishing ban on fishing labour was also worked out and suggestions were given for
improving the livelihood security of fish workers
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