8,120 research outputs found
The Sources and Sustainability of China's Economic Growth
China’s economic transformation is proceeding at different rates across different regions and sectors, and China’s most advanced regional sector, coastal industry, still lags well behind the world’s technology frontier. This paper explores the implications of these internal and international productivity disparities for China’s ability to sustain rapid economic growth. When China’s GDP catches up to U.S. GDP, Chinese living standards still will be only one quarter those of the United States. If, at that time, productivity in some major regions and sectors remains far below the average, coastal industry may have to achieve productivity that approaches or even exceeds U.S. productivity. Coastal industry’s productivity growth is then likely to slow substantially, impeding China’s overall economic growth. The paper examines the need for policies that facilitate economic integration across regions, to enable the lagging regions and sectors to catch up to coastal industry, and the prospects for continued institutional reform.China, macroeconomics, economic growth, China GDP
R&D and Technology Transfer: Firm-Level Evidence from Chinese Industry
The capacity of developing economies to narrow the gap in living standards with the OECD nations depends critically on their ability to imitate and innovate new technologies. Toward this end, developing economies have access to three avenues of technological advance: technology transfer, domestic R&D, and foreign direct investment. This paper examines the contributions of each of these avenues, as well as their interactions, to productivity and knowledge production within Chinese industry. Based on a large data set for China’s large and medium-size enterprises, the estimation results show that technology transfer – whether domestic or foreign – affects productivity only through its interactions with in-house R&D. Foreign direct investment does not appear to facilitate the adoption of market-mediated foreign technology transfer. Firms wishing to produce patentable knowledge do not benefit from technology transfer; patentable knowledge is created exclusively through in-house R&D operations.http://deepblue.lib.umich.edu/bitstream/2027.42/39968/3/wp582.pd
Accented Models: Evaluating their effectiveness in Building Energy Simulation
This report examines the effectiveness of the accented modeling method for building energy simulation. The traditional full-zone modeling method is too time consuming and in some cases unnecessary, so a more efficient building modeling method – accented modeling is introduced. The purpose of this research is to analyze if, and under what conditions, an accented building model is an effective representation of the actual building. By using DesignBuilder and EnergyPlus as software packages for model development and simulation, two building models for the Lofts on the Washington University campus in St. Louis, MO were created for comparison—a full-zone model and an accented model. This report first examines the accuracy of the full-zone model, and then, by comparing the accurate full-zone model to the accented model, shows that the accented modeling method is effective in this case
Continued study on finite element models of flagella
In previous study, we developed finite element models of flagella that show wavelike oscillation above certain load threshold. However, these baseline models were highly simplified and had inevitable limitations. In the current study, inter-doublet components have been meshed with finer setting to give more accurate results, multibody dynamics (translational joints) has introduced to allow more deflection, and inter-doublet materials have included viscoelasticity. Nondimensional waveform equations have been developed to find parameter values that allow larger deflection and frequencies close to actual cilia and flagella
Two-Component Structure of the Hbeta Broad-Line Region in Quasars. I. Evidence from Spectral Principal Component Analysis
We report on a spectral principal component analysis (SPCA) of a sample of
816 quasars, selected to have small Fe II velocity shifts with spectral
coverage in the rest wavelength range 3500--5500 \AA. The sample is explicitly
designed to mitigate spurious effects on SPCA induced by Fe II velocity shifts.
We improve the algorithm of SPCA in the literature and introduce a new
quantity, \emph{the fractional-contribution spectrum}, that effectively
identifies the emission features encoded in each eigenspectrum. The first
eigenspectrum clearly records the power-law continuum and very broad Balmer
emission lines. Narrow emission lines dominate the second eigenspectrum. The
third eigenspectrum represents the Fe II emission and a component of the Balmer
lines with kinematically similar intermediate velocity widths. Correlations
between the weights of the eigenspectra and parametric measurements of line
strength and continuum slope confirm the above interpretation for the
eigenspectra. Monte Carlo simulations demonstrate the validity of our method to
recognize cross talk in SPCA and firmly rule out a single-component model for
broad Hbeta. We also present the results of SPCA for four other samples that
contain quasars in bins of larger Fe II velocity shift; similar eigenspectra
are obtained. We propose that the Hbeta-emitting region has two kinematically
distinct components: one with very large velocities whose strength correlates
with the continuum shape, and another with more modest, intermediate velocities
that is closely coupled to the gas that gives rise to Fe II emission.Comment: 22 pages, 17 figures, accepted for publication in The Astrophysical
Journa
Evaluating Dark Energy Probes using Multi-Dimensional Dark Energy Parameters
We investigate the value of future dark energy experiments by modeling their
ability to constrain the dark energy equation of state. Similar work was
recently reported by the Dark Energy Task Force (DETF) using a two dimensional
parameterization of the equation of state evolution. We examine constraints in
a nine dimensional dark-energy parameterization, and find that the best
experiments constrain significantly more than two dimensions in our 9D space.
Consequently the impact of these experiments is substantially beyond that
revealed in the DETF analysis, and the estimated cost per ``impact'' drops by
about a factor of ten as one moves to the very best experiments. The DETF
conclusions about the relative value of different techniques and of the
importance of combining techniques are unchanged by our analysis.Comment: 6 Pages including 5 Figures. Changes from V1: Final version accepted
for publication in PRD. The text has been edited for clarity and to better
call out our main conclusions. Our conclusions and technical results are
unchange
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