1,027 research outputs found
The Linear Model under Mixed Gaussian Inputs: Designing the Transfer Matrix
Suppose a linear model y = Hx + n, where inputs x, n are independent Gaussian
mixtures. The problem is to design the transfer matrix H so as to minimize the
mean square error (MSE) when estimating x from y. This problem has important
applications, but faces at least three hurdles. Firstly, even for a fixed H,
the minimum MSE (MMSE) has no analytical form. Secondly, the MMSE is generally
not convex in H. Thirdly, derivatives of the MMSE w.r.t. H are hard to obtain.
This paper casts the problem as a stochastic program and invokes gradient
methods. The study is motivated by two applications in signal processing. One
concerns the choice of error-reducing precoders; the other deals with selection
of pilot matrices for channel estimation. In either setting, our numerical
results indicate improved estimation accuracy - markedly better than those
obtained by optimal design based on standard linear estimators. Some
implications of the non-convexities of the MMSE are noteworthy, yet, to our
knowledge, not well known. For example, there are cases in which more pilot
power is detrimental for channel estimation. This paper explains why
Major Indian spices- An introspection on variability in quality
Indian spices like black pepper, cardamom, ginger, turmeric and cinnamon are valued for their culinary and nutraceutical properties. The quality attributes that impart these properties are essential oil, oleoresin and the aroma/pungent principles. Variability in essential oil constituents of black pepper, relevance of bulk density, codex standards and role of phenolics in deciding quality traits possess great relevance in academic and industrial applications. Curing of turmeric and maturity at harvest play a crucial role in drying and curcumin content. Geographical location has great relevance in deciding the curcumin content of turmeric. Coumarin content of cinnamon and cassia has implications in industrial application. This article provides an introspection in to the research programmes on quality attributes of spices carried out at ICAR-Indian Institute of Spices Research for the last three decades in comparison with international scenario
GiRaFFE: An Open-Source General Relativistic Force-Free Electrodynamics Code
We present GiRaFFE, the first open-source general relativistic force-free
electrodynamics (GRFFE) code for dynamical, numerical-relativity generated
spacetimes. GiRaFFE adopts the strategy pioneered by McKinney and modified by
Paschalidis and Shapiro to convert a GR magnetohydrodynamic (GRMHD) code into a
GRFFE code. In short, GiRaFFE exists as a modification of IllinoisGRMHD, a
user-friendly, open-source, dynamical-spacetime GRMHD code. Both GiRaFFE and
IllinoisGRMHD leverage the Einstein Toolkit's highly-scalable infrastructure to
make possible large-scale simulations of magnetized plasmas in strong,
dynamical spacetimes on adaptive-mesh refinement (AMR) grids. We demonstrate
that GiRaFFE passes a large suite of both flat and curved-spacetime code tests
passed by a number of other state-of-the-art GRFFE codes, and is thus ready for
production-scale simulations of GRFFE phenomena of key interest to relativistic
astrophysics.Comment: 23 pages, 4 figures. Consistent with published versio
Building leadership capacity and future leaders in operational research in low-income countries: why and how?
Very limited operational research (OR) emerges from programme settings in low-income countries where the greatest burden of disease lies. The price paid for this void includes a lack of understanding of how health systems are actually functioning, not knowing what works and what does not, and an inability to propose adapted and innovative solutions to programme problems. We use the National Tuberculosis Control Programme as an example to advocate for strong programme-level leadership to steer OR and build viable relationships between programme managers, researchers and policy makers. We highlight the need to create a stimulating environment for conducting OR and identify some of the main practical challenges and enabling factors at programme level. We focus on the important role of an OR focal point within programmes and practical approaches to training that can deliver timely and quantifiable outputs. Finally, we emphasise the need to measure successful OR leadership development at programme level and we propose parameters by which this can be assessed. This paper 1) provides reasons why programmes should take the lead in coordinating and directing OR, 2) identifies the practical challenges and enabling factors for implementing, managing and sustaining OR and 3) proposes parameters for measuring successful leadership capacity development in OR
Dermatophytes from Apparently Healthy Toe-webs of Service Personnel Stationed in Northeastren Region of India
Apparently healthy toe-webs of 230 individuals belonging to various Army units stationed India were studied for dermatophytes. 35 were found positive. This revealed the presence of 28 Trichophyton mentagrophytes, 4 Epidermophyton floccosum, 2 Microsporum gypseum and 1 T. rubrum
Junior Recital:Patrick T. Keelan & Zachariah R. Oostema, Percussion
Kemp Recital Hall Saturday Afternoon November 3, 2007 5:00p.m
Dietary supplementation of Cinnamomumverum J. Presl and Curcuma longa L. extract on growth performance, antioxidant and metabolic enzymes activities in experimental rats
242-248Cinnamomumverum J. Presl and Curcuma longa L. have many biologically active metabolites, such as sterpenoids, phenolics with proven health benefits. The present study was undertaken to analyze the effect of cinnamon and turmeric extract on growth, blood parameters, and metabolic enzyme activities of albino Wistar rats. Methanol extract of cinnamon and turmeric mixture was supplemented in rat feed at 2.5 and 5% concentration, respectively and administered for 30 days. During the course of study, body weight, feed given, feed consumed data were collected at regular intervals. After the experimental period, animals were sacrificed, tissues separated, homogenized and assayed for the activity of catalase, superoxide dismutase (SOD), glutathione-s-transferase (GST), lactate dehydrogenase (LDH), malate dehydrogenase (MDH), alanine aminotransferase (AAT) and aspartate aminotransferase (AST). The results showed significant increase in liver catalase activity of treated animals and no significant changes in LDH, MDH, ALT and AST. No abnormalities were observed in the histopathology staining of tissue section. Overall, output of the present study could be useful for production of spices based antioxidant rich products for human health
Impact of migration on Kerala's economy and society
This research is first of its kind for Kerala, being the first migration
study that covers the entire state and encompasses both measurement as
well as analysis of the various types and facets of migration. Migration
has been the single-most dynamic factor in the otherwise dreary
development scenario of Kerala in the last quarter of the twentieth century.
Kerala is approaching the end of the millennium with a little cheer in
many people's homes, a major contributing factor for which has been
migration. Migration has contributed more to poverty alleviation in Kerala
than any other factor, including agrarian reforms, trade union activities
and social welfare legislation.
The study shows that nearly 1.5 million Keralites now live outside
India. They send home more than Rs.4,000 million a year by way of
remittances. Three-quarters of a million former emigrants have come
back. They live mostly on savings, work experience, and skills brought
with them from abroad. More than a million families depend on internal
migrants'earnings for subsistence, children's education and other
economic requirements. Whereas the educationally backward Muslims
from the Thrissur-Malappuram region provide the backbone of
emigration, it is the educationally forward Ezhawas, Nairs and Syrian
Christians from the former Travancore-Cochin State who form the core
of internal migration. The paper also analyses the determinants and
consequences of internal and external migration. It offers suggestions
for policy formulation for the optimum utilization of remittances sent
home by the emigrants and the expertise brought back by the return
migrants.
Migration in Kerala began with demographic expansion, but it
won't end with demographic contraction. Kerala has still time to develop
itself into an internally self-sustaining economy. The prevailing cultural
milieu of Kerala in which its people believe that anything can be achieved
through agitation and any rule can be circumvented with proper political
connections, must change and be replaced by a liberalised open economy
with strict and definite rules of the game.
JEL Classification: J21, J2
- …