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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
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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
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
Exponential stabilization of a class of stochastic system with Markovian jump parameters and mode-dependent mixed time-delays
Copyright [2010] IEEE. This material is posted here with permission of the IEEE. Such permission of the IEEE does not in any way imply IEEE endorsement of any of Brunel University's products or services. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution must be obtained from the IEEE by writing to [email protected].
By choosing to view this document, you agree to all provisions of the copyright laws protecting it.In this technical note, the globally exponential stabilization problem is investigated for a general class of stochastic systems with both Markovian jumping parameters and mixed time-delays. The mixed mode-dependent time-delays consist of both discrete and distributed delays. We aim to design a memoryless state feedback controller such that the closed-loop system is stochastically exponentially stable in the mean square sense. First, by introducing a new Lyapunov-Krasovskii functional that accounts for the mode-dependent mixed delays, stochastic analysis is conducted in order to derive a criterion for the exponential stabilizability problem. Then, a variation of such a criterion is developed to facilitate the controller design by using the linear matrix inequality (LMI) approach. Finally, it is shown that the desired state feedback controller can be characterized explicitly in terms of the solution to a set of LMIs. Numerical simulation is carried out to demonstrate the effectiveness of the proposed methods.This work was supported in part by the Engineering and Physical Sciences Research Council (EPSRC) of the U.K. under Grant GR/S27658/01, the Royal Society of the U.K., the National 973 Program of China under Grant 2009CB320600, and the Alexander von Humboldt Foundation of Germany. Recommended by Associate Editor G. Chesi
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
Robust H∞ filtering for discrete nonlinear stochastic systems with time-varying delay
This is the postprint version of the article. The official published version can be accessed from the link below - © 2007 Elsevier IncIn this paper, we are concerned with the robust H∞ filtering problem for a class of nonlinear discrete time-delay stochastic systems. The system under study involves parameter uncertainties, stochastic disturbances, time-varying delays and sector-like nonlinearities. The problem addressed is the design of a full-order filter such that, for all admissible uncertainties, nonlinearities and time delays, the dynamics of the filtering error is constrained to be robustly asymptotically stable in the mean square, and a prescribed H∞ disturbance rejection attenuation level is also guaranteed. By using the Lyapunov stability theory and some new techniques, sufficient conditions are first established to ensure the existence of the desired filtering parameters. These conditions are dependent on the lower and upper bounds of the time-varying delays. Then, the explicit expression of the desired filter gains is described in terms of the solution to a linear matrix inequality (LMI). Finally, a numerical example is exploited to show the usefulness of the results derived.This work was supported in part by the Engineering and Physical Sciences Research Council (EPSRC) of the UK under Grant GR/S27658/01, the Nuffield Foundation of the UK under Grant NAL/00630/G, the Alexander von Humboldt Foundation of Germany, the National Natural Science Foundation of China (60774073 and 10471119), the NSF of Jiangsu Province of China (BK2007075 and BK2006064), the Natural Science Foundation of Jiangsu Education Committee of China under Grant 06KJD110206, and the Scientific Innovation Fund of Yangzhou University of China under Grant 2006CXJ002
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