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H. Weller 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1898,1(3):167-171
Ohne Zusammenfassung 相似文献
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Weller T.M. Katehi L.P.B. Herman M.I. Wamhof P.D. Lee K. Kolawa E.A. Tai B.H. 《Microwave Theory and Techniques》1996,44(9):1603-1606
This paper describes recent results which pertain to the integration and reliability testing of micromachined, membrane-supported transmission line circuits. These circuits employ a 1.4-μm-thick dielectric membrane to support thin-film conducting lines above an air substrate. With regard to integration, the development of a Ka-band solid state power amplifier (SSPA) is presented. The design includes a membrane-supported Wilkinson power divider/combiner with 0.2 dB loss, along with a commercially available monolithic microwave/millimeter wave integrated circuit (MMIC) amplifier stage. Also reported are tests which investigated the survivability of membrane lines under space qualification conditions. No failures occurred as a result of thermal cycling and vibration testing at levels which reached 39.6 grms 相似文献
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In the original paper by Tesfaye and Tomizuka (ibid., vol.40, p.743-7, 1995), an asymptotic analysis was used to address the zero structure of discretized continuous-time systems expressed in the Euler (or forward difference) operator. The method was developed for application to multivariable control systems. The authors state that the analysis is flawed, so that a theorem is true as stated only when the continuous time relative degree is equal to two. They indicate how the analysis may be rectified. Tesfaye and Tomizuka acknowledge the error and the correctness of the result in this paper 相似文献
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The DNA microsatellites can be efficiently used to determine incorrect paternity attribution of cattle without genotyping of dams. Allelic frequencies of the population were determined for 12 microsatellites using the maternal alleles of 102 AI sires. The frequency of the most common microsatellite allele ranged from 0.27 to 0.58. Most loci had at least one allele that was present in only a single individual. Paternity of 9 of 173 cows (5.2%) and 3 of 102 bulls (2.9%) was excluded because putative paternal alleles were not present in progeny for at least one locus. For 4 of the 9 cows and all 3 bulls, exclusion was based on at least two loci. Mean probability of exclusion was 0.85 for cows and 0.99 for bulls. With an assumed cost of US $5 per genotype, a misidentification rate of 5%, and a discount rate of 0.05, additional profit for the Israeli-Holstein breeding program from genotyping 100 test daughters of each young sire becomes positive within 10 yr and reaches nearly US $2.4 million after 20 yr. 相似文献