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71.
Decay of hollow atoms above and below a surface 总被引:1,自引:0,他引:1
72.
Markus Eisele Ralf Kolb Erwin Kraus Christian von Ehrenstein 《Informatik-Spektrum》2007,30(6):407-412
Zusammenfassung Das Schlagwort NetWeaver ist seit einiger Zeit in unserer Branche en vogue. Wie so oft, ist es nicht leicht, Marketingaspekte
vom informatischen Wesensgehalt zu unterscheiden. Dieser Beitrag m?chte hier helfen. 相似文献
73.
Process development and accurate low‐cost characterization for OLED sealants by using a calcium test
Steffen Hergert Max Linkor Markus Korny Norbert Fruehauf 《Journal of the Society for Information Display》2007,15(6):421-429
Abstract— A calcium measurement setup was built for testing encapsulation especially for OLED applications. This setup is able to measure both reflective and transmissive cells. For the characterization of sealants, a method to compare them with other sealing products will be described. This includes the use of spacers, a homogeneous surface energy, and the geometry of the sealant line. The effects of different geometries will be discussed. The setup was designed to achieve good accuracy at a very reasonable component cost, which will allow other facilities to replicate this setup. Therefore, the construction plan as well as the list of components can be downloaded from our website (Ref. 3). 相似文献
74.
The k-nearest-neighbour (kNN) algorithm is widely applied for the estimation of forest attributes using remote sensing data. It requires a large amount of reference data to achieve satisfactory results. Usually, the number of available reference plots for the kNN-prediction is limited by the size of the area covered by a terrestrial reference inventory and remotely sensed imagery collected from one overflight. The applicability of kNN could be enhanced if adjacent images of different acquisition dates could be used in the same estimation procedure. Relative radiometric calibration is a prerequisite for this. This study focuses on two empirical calibration methods. They are tested on adjacent LANDSAT TM scenes in Austria. The first, quite conventional one is based on radiometric control points in the overlap area of two images and on the determination of transformation parameters by linear regression. The other, recently developed method exploits the kNN-cross-validation procedure. Performance and applicability of both methods as well as the impact of phenology are discussed. 相似文献
75.
OBJECTIVE: Hyaluronate degradation was analyzed in cultures of healthy tissue and tissue obtained from patients with rheumatoid arthritis. METHODS: Arthritic and healthy synovial tissues were incubated in culture with [3H]glucosamine. Labelled hyaluronate was extracted and its size determined by gel filtration. The production of low molecular weight hyaluronate was analyzed by pulse-chase experiments. Radical production was measured by a cytochrome C reduction assay. RESULTS: Healthy tissues and some arthritic tissues that did not contain significant amounts of granulocytes produced high molecular weight hyaluronate. In contrast, arthritic tissue infiltrated with granulocytes released low molecular weight hyaluronate. Pulse-chase experiments suggested that hyaluronate was degraded in these arthritic tissues. Exogenous hyaluronate was degraded only by intact tissue, but not by cells in culture obtained from synovial membranes of synovial fluids. Hyaluronate degradation was accompanied by massive oxygen radical production. Radical scavengers protected hyaluronate from degradation in synovial tissue. Some protection was achieved by superoxide and catalase or by methionine and complete protection by the iron chelators diethyltriaminepentacetic acid or deferoxamine mesylate. CONCLUSION: Degradation of hyaluronate in arthritic synovial tissue may be inhibited in tissue culture by radical scavengers. 相似文献
76.
Many problems in electromagnetics involve modeling a changing multi-dimensional field, and one can often gain insight into the underlying physical problem by animating the changes. The ability to view directly the evolving field may also provide a useful debugging tool during modeling and simulation. Here, we present a relatively simple scheme to animate a changing two-dimensional field (in this case EM wave propagation is considered in particular). The scheme permits various mappings of field values to colors, so that the color of each pixel in an image indicates the field found at the corresponding location within the computational domain. Alternatively, a gray-scale mapping can be used. A program used to construct individual frames of the animation is presented in full. Sufficient detail is given so that the customization of the code is straightforward. Public-domain software is used to view the frames as an animated sequence, or to generate an MPEG file. Some aspects of the scheme described here are tailored for use in an X-Windows or UNIX environment, but most of the important steps are independent of the operating system. Frame-generation routines are presented in FORTRAN (C versions of the code are similar and can be obtained “on-line”). The scheme presented here is relatively fast, efficient, and flexible, and should serve well as a starting point for those wanting to “roll their own” graphics. In addition, for those needing more sophisticated renderings, pointers are given to several powerful commercial and public-domain graphics packages 相似文献
77.
The synthesis of monodisperse hard segments containg 2,4-TDI and 1,4-butanediol by a simple technique is described. High purity material is obtained in good yield. The structures of these hard segments are confirmed by proton n.m.r., 13Cn.m.r., and i.r. Glass transition temperatures and melting temperatures are reported. The Tg′s of the hard segments are inversely proportional to the reciprocal of their molecular weights. The Tm′s show an odd-even effect relative to the number of 2,4-TDI units in the hard segment. 相似文献
78.
In Experiment 1, masking-level differences (MLDs) for a 500-Hz tone at five masker levels were obtained from younger and older adults. For both age groups, there were no reliable increases in MLD once the spectrum level of the masker exceeded 27 dB SPL. MLDs were larger for younger than for older adults over the range of masker levels tested. In Experiment 2, the levels of both the signal and the masker in one ear were attenuated by either 15 or 30 dB relative to their level in the other ear, which was fixed at a spectrum level of 47 dB SPL. MLDs for both age groups declined with increasing IAA and age-related differences were observed in all conditions. The findings of these experiments indicate that (1) age-related differences in MLDs exist even when the level of the masker is sufficiently high that older adults achieve their plateau performance, and (2) older listeners are not disadvantaged more than younger listeners by interaural differences in the level of the input. 相似文献
79.
Report on 2 fatal autoerotic cases. In the first case a 20-year-old man died due to the use of nitrous oxide (laughing gas) which he had used in a self-constructed breathing-machine. The nitrous oxide came from a cartridge which normally is used for aerosol cans for whipped cream. In the second case a 19-year-old man used a pressure-suit for military-jet pilots and inflated it with a 12-volt-compressor. Additionally the head was covered with 3 masks and a motorcycle helmet. Arms and legs were bound. The cause of death was a massive compression of the thorax. 相似文献
80.
JC Clouse M Rogers RC Reba JL Littlefield PB Schneider M Pollycove 《Canadian Metallurgical Quarterly》1998,39(7):11N-13N, 27N, 30N