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Ownership structure and new product development in transnational corporations in China
This article is available open access through the publisher’s website at the link below. Copyright @ 2008 United Nations.This paper examines the relationship between the ownership structure
and new product development (NPD) at the affiliates of transnational
corporations in China. Seven research hypotheses are tested on a panel
data set covering 10,000 manufacturing firms with foreign involvement
for the period 1998-2001. The results from probit and tobit models
show that contractual joint ventures, equity joint ventures and joint stock
enterprises are better organizational forms than wholly owned enterprises
for increasing both the probability and intensity of NPD. We also find
that ventures with OECD participation are more likely to be involved in
NPD than those with participation by “overseas” Chinese TNCs
Very deep spectroscopy of the bright Saturn Nebula NGC 7009 -- I. Observations and plasma diagnostics
We present very deep CCD spectrum of the bright, medium-excitation planetary
nebula NGC 7009, with a wavelength coverage from 3040 to 11000 A. Traditional
emission line identification is carried out to identify all the emission
features in the spectra, based on the available laboratory atomic transition
data. Since the spectra are of medium resolution, we use multi-Gaussian line
profile fitting to deblend faint blended lines, most of which are optical
recombination lines (ORLs) emitted by singly ionized ions of abundant
second-row elements such as C, N, O and Ne. Computer-aided emission-line
identification, using the code EMILI developed by Sharpee et al., is then
employed to further identify all the emission lines thus obtained. In total
about 1200 emission features are identified, with the faintest ones down to
fluxes 10^{-4} of H_beta. The flux errors for all emission lines, estimated
from multi-Gaussian fitting, are presented. Plots of the whole optical
spectrum, identified emission lines labeled, are presented along with the
results of multi-Gaussian fits. Plasma diagnostics using optical forbidden line
ratios are carried out. Also derived are electron temperatures and densities
from the H I, He I and He II recombination spectrum.Comment: 66 pages, 16 figures, 7 tables, paper accepted by MNRAS in Marc
Inner product computation for sparse iterative solvers on\ud distributed supercomputer
Recent years have witnessed that iterative Krylov methods without re-designing are not suitable for distribute supercomputers because of intensive global communications. It is well accepted that re-engineering Krylov methods for prescribed computer architecture is necessary and important to achieve higher performance and scalability. The paper focuses on simple and practical ways to re-organize Krylov methods and improve their performance for current heterogeneous distributed supercomputers. In construct with most of current software development of Krylov methods which usually focuses on efficient matrix vector multiplications, the paper focuses on the way to compute inner products on supercomputers and explains why inner product computation on current heterogeneous distributed supercomputers is crucial for scalable Krylov methods. Communication complexity analysis shows that how the inner product computation can be the bottleneck of performance of (inner) product-type iterative solvers on distributed supercomputers due to global communications. Principles of reducing such global communications are discussed. The importance of minimizing communications is demonstrated by experiments using up to 900 processors. The experiments were carried on a Dawning 5000A, one of the fastest and earliest heterogeneous supercomputers in the world. Both the analysis and experiments indicates that inner product computation is very likely to be the most challenging kernel for inner product-based iterative solvers to achieve exascale
Minimizing synchronizations in sparse iterative solvers for distributed supercomputers
Eliminating synchronizations is one of the important techniques related to minimizing communications for modern high performance computing. This paper discusses principles of reducing communications due to global synchronizations in sparse iterative solvers on distributed supercomputers. We demonstrates how to minimizing global synchronizations by rescheduling a typical Krylov subspace method. The benefit of minimizing synchronizations is shown in theoretical analysis and is verified by numerical experiments using up to 900 processors. The experiments also show the communication complexity for some structured sparse matrix vector multiplications and global communications in the underlying supercomputers are in the order P1/2.5 and P4/5 respectively, where P is the number of processors and the experiments were carried on a Dawning 5000A
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High-Order Dual-Port Quasi-Absorptive Microstrip Coupled-Line Bandpass Filters
In this article, we present the first demonstration of distributed and symmetrical all-band quasi-absorptive filters that can be designed to arbitrarily high orders. The proposed quasi-absorptive filter consists of a bandpass section (reflective-type coupled-line filter) and absorptive sections (a matched resistor in series with a shorted quarter-wavelength transmission line). Through a detailed analysis, we show that the absorptive sections not only eliminate out-of-band reflections but also determine the passband bandwidth (BW). As such, the bandpass section mainly determines the out-of-band roll-off and the order of the filter can be arbitrarily increased without affecting the filter BW by cascading more bandpass sections. A set of 2.45-GHz one-, two-, and three-pole quasi-absorptive microstrip bandpass filters are designed and measured. The filters show simultaneous input and output absorption across both the passband and the stopband. Measurement results agree very well with the simulation and validate the proposed design concept
Optical recombination lines as probes of conditions in planetary nebulae
Since the last IAU symposium on planetary nebulae (PNe), several deep
spectroscopic surveys of the relatively faint optical recombination lines
(ORLs) emitted by heavy element ions in PNe and H II regions have been
completed. New diagnostic tools have been developed thanks to progress in the
calculations of basic atomic data. Together, they have led to a better
understanding of the physical conditions under which the various types of
emission lines arise. The studies have strengthened the previous conjecture
that nebulae contain another component of cold, high metallicity gas, which is
too cool to excite any significant optical or UV CELs and is thus invisible via
such lines. The existence of such a plasma component in PNe and possibly also
in H II regions provides a natural solution to the long-standing problem in
nebular astrophysics, i.e. the dichotomy of nebular plasma diagnostics and
abundance determinations using ORLs and continua on the one hand and
collisionally excited lines (CELs) on the other.Comment: 8 pages, 3 figures, review talk presented to the IAU Symposium #234,
``Planetary nebulae in our Galaxy and beyond'', held in Hawaii, USA, April
3-7 200
Is Optimal Monetary and Fiscal Policy in a Small Open Economy Time Consistent?
This paper studies optimal monetary and fiscal policy in a small open economy. Two forces in the economy impose orthogonal restrictions on financing costs across governments. The first force requires constant financing costs across governments to have time consistent optimal policy of hours. The second force always asks for time-varying financing costs across governments in order to have time consistency optimal policy of consumption and real money balances. Thus, optimal monetary and fiscal policy is time inconsistent. However, if preferences (and/or productivity) satisfy certain conditions, the former force disappears and optimal monetary and fiscal policy becomes time consistent. The results hold with both flexible exchange rate regimes and fixed exchange rate regimes. The latter indicates that a credible fixed exchange rate regime does not help render optimal policy time consistent.Time consistency; Optimal monetary and fiscal policy; Small open economy.
Highlights from RHIC Spin Physics Program
The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory
delivers the world's highest energy polarized proton-proton collisions at a
center of mass energy up to 500 GeV and provides a unique opportunity to study
the quark and gluon spin structure of the proton and QCD dynamics at high
energy scale. RHIC has produced many exiting physics results in recent years.
The latest data from RHIC significantly constrain the gluon spin contribution
to the proton spin, and the parity violating single spin asymmetry are observed
for the first time in W production by both the PHENIX and STAR collaborations.
In this report, I present the latest results from the PHENIX and STAR
experiments, followed by a brief discussion of the future prospects of
transverse physics, particularly on the importance of the unique measurements
of Drell-Yan single spin asymmetry.Comment: 4 pages, MENU2010 proceeding
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