12,951 research outputs found

    Az ipari parkok a területi versenyképességben: telephelyek vagy fejlesztési csomópontok?

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    The MATLAB/C program take version 3.1 is a program for simulation of X-ray projections from 3D volume data. It is based on an older C version by Muller-Merbach as well as an extended C version by Turbell. The program can simulate 2D X-ray projections from 3D objects. These data can then be input to 3D reconstruction algorithms. Here however, we only demonstrate a couple of 2D reconstruction algorithms, written in MATLAB. Simple MATLAB examples show how to generate the take projections followed by subsequent reconstruction. Compared to the old take version, the C code have been carefully revised. A preliminary, rather untested feature of using a polychromatic X-ray source with different energy levels was already included in the old take version. The current polychromatic feature X-ray is however carefully tested. For example, it has been compared with the results from the program described by Malusek et al. We also demonstrate experiments with a polychromatic X-ray source and a Plexiglass object giving the beam-hardening artefact. Detector sensitivity for different energy levels is not included in take. However, in section~\refsec:realexperiment, we describe a technique to include the detector sensitivity into the energy spectrum. Finally, an experiment with comparison of real and simulated data were performed. The result wasn't completely successful, but we still demonstrate it. Contemporary analytical reconstruction methods for helical cone-beam CT have to be designed to handle the Long Object Problem. Normally, a moderate amount of over-scanning is sufficient for reconstruction of a certain Region-of-interest (ROI). Unfortunately, for iterative methods, it seems that the useful ROI will diminish for every iteration step. The remedies proposed here are twofold. Firstly, we use careful extrapolation and masking of projection data. Secondly, we generate and utilize projection data from incompletely reconstructed volume parts, which is rather counter-intuitive and contradictory to our initial assumptions. The results seem very encouraging. Even voxels close to the boundary in the original ROI are as well enhanced by the iterative loop as the middle part

    The Viking surface sampler

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    A surface sampler subsystem for the Viking Lander has been designed, fabricated, cleaned, and successfully tested. Testing has included component level tests to qualification environment and subsystem level tests. This development hardware has also been integrated into a System Test Bed (STB) for the lander system. In addition to the normal dynamic and thermal environments the surface sampler hardware has been tested in an aircraft to simulate the effects of the reduced Martian gravity. Although problems have been encountered with the first-build and integration, the basic design appears to be sound and hardware qualification is scheduled for late 1973

    Word-level Symbolic Trajectory Evaluation

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    Symbolic trajectory evaluation (STE) is a model checking technique that has been successfully used to verify industrial designs. Existing implementations of STE, however, reason at the level of bits, allowing signals to take values in {0, 1, X}. This limits the amount of abstraction that can be achieved, and presents inherent limitations to scaling. The main contribution of this paper is to show how much more abstract lattices can be derived automatically from RTL descriptions, and how a model checker for the general theory of STE instantiated with such abstract lattices can be implemented in practice. This gives us the first practical word-level STE engine, called STEWord. Experiments on a set of designs similar to those used in industry show that STEWord scales better than word-level BMC and also bit-level STE.Comment: 19 pages, 3 figures, 2 tables, full version of paper in International Conference on Computer-Aided Verification (CAV) 201

    Panel design effects on response rates and response quality

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    To understand changes in individuals' opinions and attitudes it would be bestto collect data through panels. Such panels, however, often cause irritationamong respondents, resulting in low response rates and low response quality.We address whether this problem can be alleviated by designing a panel surveyin an alternative way. For this purpose, we perform two field studies wherewe measure the effects of several panel design characteristics on response ratesand response quality. These characteristics include the number of waves andthe time between subsequent waves, which may either be fixed or random.Our findings suggest that response rates and response quality can be im-proved significantly by surveying at random time intervals. It is then crucialthat panel members are not informed about the dates they will be surveyed,because in this case respondents are less likely to develop expectations as towhen they will be surveyed again. The methodology we put forward can be used to improve the e±ciency of a panel study by carefully calibrating thestudies' panel designs parameters.nonresponse;panel conditioning;randomized sampling;time sampling;panel design

    Guest editorial

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    Immunsuppressiva-Medikamentenspiegelmessung – reine Routine? / Immunosuppressant drug monitoring – a routine undertaking?

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    The quantitative assessment of immunosuppressant drug levels is still one of the most challenging therapeutic drug monitoring procedures in clinical routine. During the past years, several technical developments matured to useable methods. In addition to immunoassays, liquid chromatography- tandem mass spectrometry has become a key method in immunosuppressant therapeutic drug monitoring. This overview should aid in understanding the advantages and disadvantages of the various assays and methods. UKNEQAS proficiency testing results are used for an inter-assay comparison approach

    ANALISIS PENGARUH PENERAPAN CORPORATE GOVERNANCE DAN PROFITABILITAS TERHADAP PERINGKAT OBLIGASI DAN YIELD OBLIGASI (Studi Empiris terhadap Perusahaan yang terdaftar di Indonesia Bond Pricing Agency, PEFINDO, dan Bursa Efek Indonesia)

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    This study aims to determine the effect of institutional ownership, managerial ownership, independent board, audit committee, audit quality and profitability of the bond ratings and yields. The population in this study is the issuing company bonds circulating in Indonesian Bond Pricing Agency (IPBA). Sampling technique used is purposive sampling. The analytical tool used is multiple linear regression analysis. Based on the results of tests performed can be concluded that: institutional ownership does not affect the bond ratings. Institutional ownership negatively affect bond yields. Managerial ownership negatively affect bond ratings. Managerial ownership has no effect on bond yields. Independent board does not affect the bond ratings. Independent board negative effect on bond yields. The audit committee has a positive influence on bond ratings. The audit committee has a negative influence on bond yields. Quality audits positive effect on bond ratings. Audit quality has no effect on bond yields. Profitability does not affect the bond ratings. Profitability negatively affect bond yields
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