7,121 research outputs found
A New International Division of Labor in Europe: Offshoring and Outsourcing to Eastern Europe
Europe is reorganizing its international value chain. I document these changes in Europe’s international organization of production with new survey data of Austrian and German firms investing in Eastern Europe. I show estimates of the share of intra-firm trade between Austria and Germany on the one hand and Eastern Europe on the other. Furthermore, I present empirical evidence of the drivers of the new division of labor in Europe. I find among other things that falling trade costs and falling corruption levels as well as improvements in the contracting environment in Eastern Europe are affecting the level of intra-firm imports from Eastern Europe. They are also favoring outsourcing over offshoring. Low organizational costs of hierarchies and large costs of hold-up (when there are no alternative investors in Old Europe or no alternative suppliers in Eastern Europe) are favoring offshoring over outsourcing. Tax holidays granted by host countries in Eastern Europe also mildly affect the organizational choice
Quantum Theory of a Resonant Photonic Crystal
We present a quantum model of two-level atoms localized in a 3D lattice,
based on the Hopfield theory of exciton polaritons. In addition to a
polaritonic gap at the exciton energy, a photonic bandgap opens up at the
Brillouin zone boundary. Upon tuning the lattice period or angle of incidence
to match the photonic gap with the exciton energy, one obtains a combined
polaritonic and photonic gap as a generalization of Rabi splitting. For typical
experimental parameters, the size of the combined gap is on the order of 25
cm^{-1}, up to 10^5 times the detuned gap size. The dispersion curve contains a
branch supporting slow-light modes with vanishing exciton probability density.Comment: 4 pages, 3 figure
Implementation of an Energy Management System in Colombian Manufacturing - A Methodological Approach
This paper aims to analyze mechanisms such as the Energy management systems approach in industry 4.0. The paper is a review of techniques for optimizing energy consumption with energy efficiency, advanced metering infrastructure and rational and efficient use of energy to reduce the pollution as well as to strengthen Industry 4.0 models and the monitoring and management opportunities that exist with the implementation of this models in Colombia.Universidad Tecnológica de Bolíva
Impact of time to appropriate therapy on mortality in patients with vancomycin-intermediate Staphylococcus aureus infection
Despite the increasing incidence of vancomycin-intermediate Staphylococcus aureus (VISA) infections, few studies have examined the impact of delay in receipt of appropriate antimicrobial therapy on outcomes in VISA patients. We examined the effects of timing of appropriate antimicrobial therapy in a cohort of patients with sterile-site methicillin-resistant S. aureus (MRSA) and VISA infections. In this single-center, retrospective cohort study, we identified all patients with MRSA or VISA sterile-site infections from June 2009 to February 2015. Clinical outcomes were compared according to MRSA/VISA classification, demographics, comorbidities, and antimicrobial treatment. Thirty-day all-cause mortality was modeled with Kaplan-Meier curves. Multivariate logistic regression analysis (MVLRA) was used to determine odds ratios for mortality. We identified 354 patients with MRSA (n = 267) or VISA (n = 87) sterile-site infection. Fifty-five patients (15.5%) were nonsurvivors. Factors associated with mortality in MVLRA included pneumonia, unknown source of infection, acute physiology and chronic health evaluation (APACHE) II score, solid-organ malignancy, and admission from skilled care facilities. Time to appropriate antimicrobial therapy was not significantly associated with outcome. Presence of a VISA infection compared to that of a non-VISA S. aureus infection did not result in excess mortality. Linezolid use was a risk for mortality in patients with APACHE II scores of ≥14. Our results suggest that empirical vancomycin use in patients with VISA infections does not result in excess mortality. Future studies should (i) include larger numbers of patients with VISA infections to confirm the findings presented here and (ii) determine the optimal antibiotic therapy for critically ill patients with MRSA and VISA infections
Optimal Path to Epigenetic Switching
We use large deviation methods to calculate rates of noise-induced
transitions between states in multistable genetic networks. We analyze a
synthetic biochemical circuit, the toggle switch, and compare the results to
those obtained from a numerical solution of the master equation.Comment: 5 pages. 2 figures, uses revtex 4. PR-E reviewed for publicatio
Degenerate four-wave mixing in triply-resonant Kerr cavities
We demonstrate theoretical conditions for highly-efficient degenerate
four-wave mixing in triply-resonant nonlinear (Kerr) cavities. We employ a
general and accurate temporal coupled-mode analysis in which the interaction of
light in arbitrary microcavities is expressed in terms a set of coupling
coefficients that we rigorously derive from the full Maxwell equations. Using
the coupled-mode theory, we show that light consisting of an input signal of
frequency can, in the presence of pump light at
, be converted with quantum-limited efficiency into an output shifted
signal of frequency , and we derive expressions for
the critical input powers at which this occurs. We find that critical powers in
the order of 10mW assuming very conservative cavity parameters (modal volumes
cubic wavelengths and quality factors . The standard
Manley-Rowe efficiency limits are obtained from the solution of the classical
coupled-mode equations, although we also derive them from simple
photon-counting "quantum" arguments. Finally, using a linear stability
analysis, we demonstrate that maximal conversion efficiency can be retained
even in the presence of self- and cross-phase modulation effects that generally
act to disrupt the resonance condition.Comment: 13 pages, 8 figures. To appear in Physical Review
An Efficient Representation Format for Fuzzy Intervals Based on Symmetric Membership Functions
International audienceThis paper proposes a novel implementation of fuzzy arithmetics that exploits both fuzzy intervals and hardware specificities. First, we propose and evaluate the benefit of an alternative representation format to the traditional lower-upper and midpoint-radius representation formats for intervals. Thanks to the proposed formats, we show that it is possible to halve the number of operations and memory requirements compared to conventional methods. Then, we show that operations on fuzzy intervals are sensitive to hardware specificities of accelerators such as GPU. These include static rounding, memory usage, instruction level parallelism (ILP) and thread-level parallelism (TLP). We develop a library of fuzzy arithmetic operations in CUDA and C++ over several formats. The proposed library is evaluated using compute-bound and memory-bound benchmarks on Nvidia GPUs, and shows a performance gain of 2 to 20 over traditional approaches
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