158 research outputs found
China's economy, India's economy, comparative development
Editors' Introduction to the symposium "Comparing China and India: Structural Change and Development"China's economy, India's economy, comparative development
Growth Prospects in China and India Compared
This paper compares the growth prospects of China and India through a growth accounting analysis. Consistent time series for capital stock and employment are constructed using available survey data, and recent revisions to the national accounts for both countries are incorporated. The results allow for a discussion of the sources of growth in both countries, and a consideration of each country's rate of potential growth in light of the outlook for national savings, as demographic shifts occur in each country.Growth accounting; potential growth; capital measurement; demographics; China; India
Winds in Collision: high-energy particles in massive binary systems
High-resolution radio observations have revealed that non-thermal radio
emission in WR stars arises where the stellar wind of the WR star collides with
that of a binary companion. These colliding-wind binary (CWB) systems offer an
important laboratory for investigating the underlying physics of particle
acceleration. Hydrodynamic models of the binary stellar winds and the
wind-collision region (WCR) that account for the evolution of the electron
energy spectrum, largely due to inverse Compton cooling, are now available.
Radiometry and imaging obtained with the VLA, MERLIN, EVN and VLBA provide
essential constraints to these models. Models of the radio emission from WR146
and WR147 are shown, though these very wide systems do not have defined orbits
and hence lack a number of important model parameters. Multi-epoch VLBI imaging
of the archetype WR+O star binary WR140 through a part of its 7.9-year orbit
has been used to define the orbit inclination, distance and the luminosity of
the companion star to enable the best constraints for any radio emitting CWB
system. Models of the spatial distribution of relativistic electrons and ions,
and the magnetic energy density are used to model the radio emission, and also
to predict the high energy emission at X-ray and gamma-ray energies. It is
clear that high-energy facilities e.g. GLAST and VERITAS, will be important for
constraining particle acceleration parameters such as the spectral index of the
energy spectrum and the acceleration efficiency of both ions and electrons, and
in turn, identify unique models for the radio spectra. This will be especially
important in future attempts to model the spectra of WR140 throughout its
complete orbit. A WCR origin for the synchrotron emission in O-stars, the
progenitors of WR stars, is illustrated by observations of Cyg OB2 No. 9.Comment: Invited review at the 8th EVN Symposium, Torun September 26-29, 2006.
11 pages, 12 figure
Radio observations of the massive stellar cluster Westerlund 1
High-dynamic range radio observations of Westerlund 1 are presented that
detect a total of 21 stars in the young massive stellar cluster, the richest
population of radio emitting stars known for any young massive galactic cluster
in the Galaxy. We will discuss some of the more remarkable objects, including
the highly radio luminous supergiant B[e] star W9, with an estimated mass-loss
rate ~10^{-3} solarmass/yr, comparable to that of eta Carina, along with the
somewhat unusual detection of thermal emission from almost all the cool red
supergiants and yellow hypergiants. There is strong supporting evidence from
X-ray observations that each of the WR stars with radio emission are likely to
be colliding-wind binariesComment: To appear in the proceedings of "Massive Stars: Fundamental
Parameters and Circumstellar Interactions". 2 pages, 1 figur
The Long Waiting (for Joseph Kriesler 1919-2002)
In the small room inside my mother’s Chest, a weeping sound that whispers across The tall grass of late summer, carries my mothe
Baggage
Great brown trunks with metal buckles, belts, train trunks, black leather and steel rivets, large round stamps: Austria, Munich, Bremen, Budapest. Piles of trunks and suitcases to the ceiling. Rooms of suitcases, bird-cages, baskets
Room-Temperature Alternative to the Arbuzov Reaction: The Reductive Deoxygenation of Acyl Phosphonates
The reductive deoxygenation of acyl phosphonates using a Wolff−Kishner-like sequence is described. This transformation allows direct access to alkyl phosphonates from acyl phosphonates at room temperature. The method can be combined with acyl phosphonate synthesis into a one pot, four-step procedure for the conversion of carboxylic acids into alkyl phosphonates. The methodology works well for a variety of aliphatic acids and shows a functional group tolerance similar to that of other hydrazone-forming reactions
Partnering People with Deep Learning Systems: Human Cognitive Effects of Explanations
Advances in “deep learning” algorithms have led to intelligent systems that provide automated classifications of unstructured data. Until recently these systems could not provide the reasons behind a classification. This lack of “explainability” has led to resistance in applying these systems in some contexts. An intensive research and development effort to make such systems more transparent and interpretable has proposed and developed multiple types of explanation to address this challenge. Relatively little research has been conducted into how humans process these explanations. Theories and measures from areas of research in social cognition were selected to evaluate attribution of mental processes from intentional systems theory, measures of working memory demands from cognitive load theory, and self-efficacy from social cognition theory. Crowdsourced natural disaster damage assessment of aerial images was employed using a written assessment guideline as the task. The “Wizard of Oz” method was used to generate the damage assessment output of a simulated agent. The output and explanations contained errors consistent with transferring a deep learning system to a new disaster event. A between-subjects experiment was conducted where three types of natural language explanations were manipulated between conditions. Counterfactual explanations increased intrinsic cognitive load and made participants more aware of the challenges of the task. Explanations that described boundary conditions and failure modes (“hedging explanations”) decreased agreement with erroneous agent ratings without a detectable effect on cognitive load. However, these effects were not large enough to counteract decreases in self-efficacy and increases in erroneous agreement as a result of providing a causal explanation. The extraneous cognitive load generated by explanations had the strongest influence on self-efficacy in the task. Presenting all of the explanation types at the same time maximized cognitive load and agreement with erroneous simulated output. Perceived interdependence with the simulated agent was also associated with increases in self-efficacy; however, trust in the agent was not associated with differences in self-efficacy. These findings identify effects related to research areas which have developed methods to design tasks that may increase the effectiveness of explanations
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