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971.
972.
973.
The forward characteristics of different epitazial n-n+ silicon Schottky barrier diodes have been studied up to high current densities. Modulation has been observed in these experiments, that means an increase in charge carrier density in the series resistance region, i.e. in the epitaxial n-layer. By appropriate analysis of the forward characteristics the carrier density can be determined as a function of the current density. In accordance with the predictions of Scharfetter we find that the modulation increases with the barrier height but decreases with rising donor density. Furthermore it is shown how modulation is affected by recombination centres. The modulation effect is attenuated by irradiation with 1·5 MeV electrons and in a similar manner by doping the epitaxial layer with gold. 相似文献
974.
The discussion about how to treat author self-citations driven by policy application and quality measurement intensified in the last years. The definition introduced by Snyder and Bonzi has — in lack of any reasonable alternative — been used in bibliometric practice for science policy purposes. This method, however, does not take into account the weight of self-citing authors among coauthors of both the cited and citing papers. The objective of the present paper is to quantify the weight of self-citations with respect to co-authorship. The analysis is conducted at two levels: at the macro level, namely, for fifteen subject fields and the most active forty countries, and at the meso level, for a set of selected research institutions. 相似文献
975.
Eranti Esa Kärnä Tuomo 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1994,28(3):151-155
There are fascinating economical and technical challenges facing field developers in the Russian continental shelf. As far as production platforms and offshore terminal structures are concerned one has to find out how to build them so that attractive investment economics can be achieved. Controlling project risks and reducing key uncertainties are found to have significance in this respect. Different ice resistant offshore structures and their construction methods are illustrated in this paper. The cost structure and technical features of the production platform types are also discussed with special attention given to the Russian construction facilities and equipment. Extreme ice loads and ice induced vibrations still remain areas of some uncertainty in offshore platforms. An approach to solve complicated interaction cases involving extreme first year ridges and hummock fields is outlined. Means to control ice loads and vibrations are discussed. 相似文献
976.
Rhode Heyns G. Weiss Schwaibold Steingroever Hans Müller Kanitz H. J. Steinbeck K. Felix K. Höll P. de Fremery Edward Hofmann Konrad Lang O. Windhausen Trendtel W. Leithe W. Schulze Ilse Gaede v. Noël Jesser H. Elsner Pieper W. Schreiber Rudolf Abderhalden Renate Teske Hanson I. Stahn Krzywanek Fr. Bartschat Lars Erlandsen Ad. Hanak W. Bartels Kluge E. -E. Bauke Karl Bernhard G. Steinhoff W. Hämmerle C. I. Kruisheer Brüning Reichard K. J. Demeter M. Gordienko Flössner Jahr Diemair H. Mohler 《European Food Research and Technology》1939,78(1):48-112
977.
978.
Ph. Gremillet M. Jourlin Cph Bron J. Schüpbach H. P. Gautschi Th. Bächi 《Machine Vision and Applications》1991,4(4):263-270
This article describes the digital treatments needed to reconstruct spatial information at a 40-nm depth resolution of entire cells from transmission electron microscopic images of serial sections containing laser-induced topographical references. The use of a scanning transmission electron microscope (STEM) allows the acquisition of images with high contrast and good resolution at medium magnification. The scanning of our specimens at video frequencies is an attractive way to link a STEM with an image processing system. The magnetic hysteresis of the spools responsible for the electron scanning induces image deformations that have to be modelized and rectified before registering the images corrected for cutting-induced deformations. 相似文献
979.
980.
H. Alles A. V. Babkin P. J. Hakonen J. P. Ruutu J. P. Saramäki A. Ya. Parshin 《Journal of Low Temperature Physics》1995,101(3-4):519-523
On vicinal planes the surface stiffness is quite anisotropic and a crystal defect, terminating at the interface, is predicted to produce a 10...50 nm deep dimple with macroscopic lateral extent (up to a few mm). We have searched for such depressions using high resolution interferometry. Sometimes our measured interferograms of the super fluid/solid interface display unexpectedly large dimples. The volume and shape of the observed objects suggest that these dimples are caused by bundles of about 10 dislocations. 相似文献