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31.
W. Herbert Morrison III 《Journal of the American Oil Chemists' Society》1990,67(7):431-432
The Soxtec System and the AOCS method were compared for oil determination in soybeans, and no significant difference was found
between the two methods. The Root Mean Square Error (RMSE) and standard deviation for individual samples were higher for the
Soxtec, but this was attributable to the regrinding step used. The study suggests that the Soxtec System is faster and just
as accurate as the AOCS method. 相似文献
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33.
Micro-Raman temperature measurements for electric field assessment in active AlGaN-GaN HFETs 总被引:1,自引:0,他引:1
Rajasingam S. Pomeroy J.W. Kuball M. Uren M.J. Martin T. Herbert D.C. Hilton K.P. Balmer R.S. 《Electron Device Letters, IEEE》2004,25(7):456-458
Temperature profiles in the source/drain (S/D) opening of a single finger AlGaN-GaN heterostructure field-effect transistor were studied at increasing S/D voltages by micro-Raman spectroscopy with <1 /spl mu/m spatial resolution. These profiles imply high field regions near the gate edge of length /spl sim/0.4 /spl mu/m for S/D voltages between 45 and 75 V. Electric field strengths of /spl sim/1.2 and /spl sim/1.9 MV/cm are estimated for 45 and 75 V S/D voltage. The experimental results are in excellent agreement with 2-D Monte Carlo simulations. 相似文献
34.
Short-time Fourier transform (STFT), Gabor transform (GT), wavelet transform (WT), and the Wigner-Ville distribution (WVD) are just some examples of time-frequency analysis methods which are frequently applied in biomedical signal analysis. However, all of these methods have their individual drawbacks. The STFT, GT, and WT have a time-frequency resolution that is determined by algorithm parameters and the WVD is contaminated by cross terms. In 1993, Mallat and Zhang introduced the matching pursuit (MP) algorithm that decomposes a signal into a sum of atoms and uses a cross-term free pseudo-WVD to generate a data-adaptive power distribution in the time-frequency space. Thus, it solved some of the problems of the GT and WT but lacks phase information that is crucial e.g., for synchronization analysis. We introduce a new time-frequency analysis method that combines the MP with a pseudo-GT. Therefore, the signal is decomposed into a set of Gabor atoms. Afterward, each atom is analyzed with a Gabor analysis, where the time-domain gaussian window of the analysis matches that of the specific atom envelope. A superposition of the single time-frequency planes gives the final result. This is the first time that a complete analysis of the complex time-frequency plane can be performed in a fully data-adaptive and frequency-selective manner. We demonstrate the capabilities of our approach on a simulation and on real-life magnetoencephalogram data. 相似文献
35.
There is much to be gained from an integration of sensory evaluation and market research to provide a full understanding of the overall evaluation and acceptance of food. This can be achieved if research paradigms and practical applications are broadened to address key issues: the choice of appropriate research subjects, the use of realistic foods and of more complex and realistic environments, the appropriate selection of sensory methods, and the consideration of contextual influences. Improved research paradigms will contribute to our theories of how human eating is controlled and, hence, to the use of this information in product development and biomedical applications. 相似文献
36.
Up to now, C–V profiling through isotype heterojunctions has been performed assuming a uniform dielectric permittivity throughout the heterostructure. We extend the interpretation of C–V data to the case of a semiconductor with position-dependent dielectric permittivity, and we show that the variation of the dielectric permittivity across an isotype heterojunction interface has no effect on the determination of the heterojunction band discontinuity and the interface charge density. 相似文献
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