1,106 research outputs found

    Government Patent Policy: an Analysis of the Effects of Three Alternative Patent Policies on Technology of Government Inventions

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    The effects of present and proposed Government patent policies on the process of technology transfer and the commercialization of inventions resulting from Government sponsored research are addressed. The function of the patent system in Government research and the value of patents resulting from government sponsored research are examined. Three alternative patent policies, title in the contractor, title in the Government, and the waiver policy, are examined in terms of their effect on the commercialization of inventions, industrial competitions, disclosure of inventions, participation of research contractors and administrative costs. Efforts to reform the present Government patent policy are also described

    Topological lower bounds for the chromatic number: A hierarchy

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    This paper is a study of ``topological'' lower bounds for the chromatic number of a graph. Such a lower bound was first introduced by Lov\'asz in 1978, in his famous proof of the \emph{Kneser conjecture} via Algebraic Topology. This conjecture stated that the \emph{Kneser graph} \KG_{m,n}, the graph with all kk-element subsets of {1,2,...,n}\{1,2,...,n\} as vertices and all pairs of disjoint sets as edges, has chromatic number n−2k+2n-2k+2. Several other proofs have since been published (by B\'ar\'any, Schrijver, Dolnikov, Sarkaria, Kriz, Greene, and others), all of them based on some version of the Borsuk--Ulam theorem, but otherwise quite different. Each can be extended to yield some lower bound on the chromatic number of an arbitrary graph. (Indeed, we observe that \emph{every} finite graph may be represented as a generalized Kneser graph, to which the above bounds apply.) We show that these bounds are almost linearly ordered by strength, the strongest one being essentially Lov\'asz' original bound in terms of a neighborhood complex. We also present and compare various definitions of a \emph{box complex} of a graph (developing ideas of Alon, Frankl, and Lov\'asz and of \kriz). A suitable box complex is equivalent to Lov\'asz' complex, but the construction is simpler and functorial, mapping graphs with homomorphisms to Z2\Z_2-spaces with Z2\Z_2-maps.Comment: 16 pages, 1 figure. Jahresbericht der DMV, to appea

    Spectroscopic study of optically induced ultrafast electron dynamics in gold

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    Copyright © 2007 The American Physical SocietyUsing a supercontinuum pulse as a probe, we have measured the transient reflectivity spectra of a thin film of gold for different values of the pump-probe time delay. The wavelength lambda(x) at which the measured transient reflectivity changes sign has been found to depend upon the time delay, leading to bipolar time resolved signals. The time dependence of lambda(x) has been shown to be consistent with calculations that take into account the full dependence of the reflectivity upon the electron occupation number, and to contradict qualitatively a model in which the signal is assumed to be directly proportional to the occupation number. The shift of lambda(x) has been found to persist at time delays that are much longer than the time required for the electrons to thermalize. Therefore the bipolar reflectivity signals do not necessarily contain a contribution from nonthermalized electrons, as has been previously assumed

    Fluorescence suppression using micro-scale spatially offset Raman spectroscopy

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    We present a new concept of fluorescence suppression in Raman microscopy based on micro-spatially offset Raman spectroscopy which is applicable to thin stratified turbid (diffusely scattering) matrices permitting the retrieval of the Raman signals of sublayers below intensely fluorescing turbid over-layers. The method is demonstrated to yield good quality Raman spectra with dramatically suppressed fluorescence backgrounds enabling the retrieval of Raman sublayer signals even in situations where conventional Raman microscopy spectra are fully overwhelmed by intense fluorescence. The concept performance was studied theoretically using Monte Carlo simulations indicating the potential of up to an order or two of magnitude suppression of overlayer fluorescence backgrounds relative to the Raman sublayer signals. The technique applicability was conceptually demonstrated on layered samples involving paints, polymers and stones yielding fluorescence suppression factors between 12 to above 430. The technique has potential applications in a number of analytical areas including cultural heritage, archaeology, polymers, food, pharmaceutical, biological, biomedical, forensics and catalytic sciences and quality control in manufacture

    Novel Rotational Dynamics in Anisotropic Fluid Media Studied by Polarisation Resolved Picosecond TCSPC

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    Do evolutionary algorithms indeed require random numbers? Extended study

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    An inherent part of evolutionary algorithms, that are based on Darwin theory of evolution and Mendel theory of genetic heritage, are random processes. In this participation, we discuss whether are random processes really needed in evolutionary algorithms. We use n periodic deterministic processes instead of random number generators and compare performance of evolutionary algorithms powered by those processes and by pseudo-random number generators. Deterministic processes used in this participation are based on deterministic chaos and are used to generate periodical series with different length. Results presented here are numerical demonstration rather than mathematical proofs. We propose that a certain class of deterministic processes can be used instead of random number generators without lowering of evolutionary algorithms performance. © Springer International Publishing Switzerland 2013

    Do productive firms get external finance? Evidence from Chinese listed manufacturing firms

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    © 2019 Elsevier Inc. Due to information asymmetry problem in financial markets good quality firms often find it difficult to prove to external finance providers about their true quality and to distinguish themselves from bad quality firms. We argue that instead of sending indirect signals to financial market good quality firms could focus on improving their productivity to obtain external finance. Besides relying solely on firms' balance sheet information external finance providers using firms' TFP or labour productivity information would have a true knowledge of firms' efficiency and risk. Overall, using a panel of 1591 Chinese listed manufacturing firms between 2003 and 2016 we find that productivity measured by TFP or labour productivity is statistically and economically important and positive in determining firms' external finance, i.e. total leverage, new issue of equity and long-term debt. We find that productivity is helpful for firms to raise new equity finance, but only some weak results for total leverage and long-term debt. Such results hold for both the whole sample and private firm sample. We also find that large and/or old firms and exporting firms are able to make better use of their productivity to gain external finance than their respective counterparts, i.e. small young firms and non-exporting firms. The causality of the regression results is also confirmed by difference-in-difference tests using an exogenous industrial policy shock

    Effect of particle properties of powders on the generation and transmission of raman scattering

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    Transmission Raman measurements of a 1 mm thick sulfur-containing disk were made at different positions as it was moved through 4 mm of aspirin (150-212 mu m) or microcrystalline cellulose (Avicel) of different size ranges (<38, 53-106, and 150-212 mu m). The transmission Raman intensity of the sulfur interlayer at 218 cm(-1) was lower when the disk was placed at the top or bottom of the powder bed, compared to positions within the bed and the difference between the sulfur intensity at the outer and inner positions increased with Avicel particle size. Also, the positional intensity difference was smaller for needle-shaped aspirin than for granular Avicel of the same size. The attenuation coefficients for the propagation of the exciting laser and transmitted Raman photons through the individual powders were the same but decreased as the particle size of Avicel increased; also, the attenuation coefficients for propagation through 150-212 mu m aspirin were almost half of those through similar sized Avicel particles. The study has demonstrated that particulate size and type affect transmitted Raman intensities and, consequently, such factors need to be considered in the analysis of powders, especially if particle properties vary between the samples

    Analytical capability of defocused μ-SORS in the chemical interrogation of thin turbid painted layers

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    © The Author(s) 2015. A recently developed micrometer-scale spatially offset Raman spectroscopy (m-SORS) method provides a new analytical capability for investigating non-destructively the chemical composition of sub-surface, micrometer-scale thickness, diffusely scattering layers at depths beyond the reach of conventional confocal Raman microscopy. Here, we demonstrate experimentally, for the first time, the capability of μ-SORS to determine whether two detected chemical components originate from two separate layers or whether the two components are mixed together in a single layer. Such information is important in a number of areas, including conservation of cultural heritage objects, and is not available, for highly turbid media, from conventional Raman microscopy, where axial (confocal) scanning is not possible due to an inability to facilitate direct imaging within the highly scattering sample. This application constitutes an additional capability for μ-SORS in addition to its basic capacity to determine the overall chemical make-up of layers in a turbid system
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