61,301 research outputs found
Using DDC to create a visual knowledge map as an aid to online information retrieval
Selection of search terms in an online search environment can be facilitated by the visual display of a knowledge map showing the various concepts and their links. This paper reports on a preliminary research aimed at designing a prototype knowledge map using DDC and its visual display. The prototype knowledge map created using the Protæ#169;gæ#169; and TGViz freeware has been demonstrated, and further areas of research in this field are discussed
(WP 2013-07) Terms of Trade Shocks and Private Savings in the Developing Countries
Economic agents in the developing countries are subject to tight credit constraints, which are more pronounced during bad state of nature. Thus, adverse shocks to commodity prices in the world market can force them to reduce savings by a larger amount than they would otherwise have. Empirical analysis using a dynamic GMM model and data from 45 developing countries confirm that most of the determinants of savings identified in the literature also apply to the developing countries. The transitory component in the terms of trade have a larger positive impact than the permanent component. This reflects the lack of access to foreign borrowing. Although the impact of terms of trade shocks is found to be asymmetric, the magnitude of the impact appears to be relatively small. The results are robust for alternative estimators, determinants and country groupings
Private Savings in Transition Economies: Are There Terms of Trade Shocks?
Economic agents in the transition economies are subject to tight credit constraints, which are more pronounced during bad state of nature. Thus, adverse shocks to commodity prices in the world market can force them to reduce savings by a larger amount than they would otherwise have. Empirical analysis using a dynamic panel model and data from 21 transition economies confirm that most of the determinants of savings identified in the literature also apply to the transition economies. The transitory component in the terms of trade have a larger positive impact than the permanent component. This reflects the lack of access to foreign borrowing. Although the impact of terms of trade shocks is found to be asymmetric, the magnitude of the impact appears to be small. The results are robust for alternative estimators, determinants and country groupings
Molecular motors: design, mechanism and control
Biological functions in each animal cell depend on coordinated operations of
a wide variety of molecular motors. Some of the these motors transport cargo to
their respective destinations whereas some others are mobile workshops which
synthesize macromolecules while moving on their tracks. Some other motors are
designed to function as packers and movers. All these motors require input
energy for performing their mechanical works and operate under conditions far
from thermodynamic equilibrium. The typical size of these motors and the forces
they generate are of the order of nano-meters and pico-Newtons, respectively.
They are subjected to random bombardments by the molecules of the surrounding
aqueous medium and, therefore, follow noisy trajectories. Because of their
small inertia, their movements in the viscous intracellular space exhibits
features that are characteristics of hydrodynamics at low Reynold's number. In
this article we discuss how theoretical modeling and computer simulations of
these machines by physicists are providing insight into their mechanisms which
engineers can exploit to design and control artificial nano-motors.Comment: 11 pages, including 8 embedded EPS figures; Invited article, accepted
for Publication in "Computing in Science and Engineering" (AIP & IEEE
Does Exchange Rate Variability Depress Trade Flows ? Evidence From Error Correction Models
This paper examines the impact of exchange rate volatility on the trade flows of the G-7 countries in the context of a multivariate error-correction model. The error-correction models do not show any sign of parameter instability. The results indicate that the exchange rate volatility has a significant negative impact on the volume of exports in each of the G-7 countries. Assuming market participants are risk averse, these results imply that exchange rate uncertainty causes them to reduce their activities, change prices, or shift sources of demand and supply in order to minimize their exposure to the effects of exchange rate volatility. This, in turn, can change the distribution of output across many sectors in these countries. It is quite possible that the surprisingly weak relationship between trade flows and exchange rate volatility reported in several previous studies are due to insufficient attention to the stochastic properties of the relevant time series
100 years of Einstein's theory of Brownian motion: from pollen grains to protein trains
Experimental verification of the theoretical predictions made by Albert
Einstein in his paper, published in 1905, on the molecular mechanisms of
Brownian motion established the existence of atoms. In the last 100 years
discoveries of many facets of the ubiquitous Brownian motion has revolutionized
our fundamental understanding of the role of {\it thermal fluctuations} in the
exotic structures and complex dynamics exhibited by soft matter like, for
example, colloids, gels, etc. The domain of Brownian motion transcends the
traditional disciplinary boundaries of physics and has become an area of
multi-disciplinary research. Brownian motion finds applications also in earth
and environmental sciences as well as life sciences. Nature exploits Brownian
motion for running many dynamical processes that are crucial for sustaining
life. In the first one-third of this article I present a brief historical
survey of the initial period, including works of Brown and Einstein. In the
next one-third I introduce the main concepts and the essential theoretical
techniques used for studying translational as well as rotational Brownian
motions and the effects of time-independent potentials. In the last one-third
of this article I discuss some contemporary problems on Brownian motion in
time-dependent potentials, namely, {\it stochastic resonance} and {\it Brownian
ratchet}, two of the hottest topics in this area of interdisciplinary research.Comment: 15 pages, LATEX, Based on the inaugural lecture in the Horizon
Lecture Series organized by the Physics Society of I.I.T. Kanpur, in the
"World Year of Physics 2005
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