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1.
We study the functions on the punctured n-dimensional sphere having zero integrals over all admissible “hemispheres.” We find a condition for the point to be a removable set for this class of functions and show that the condition cannot be dropped or substantially improved. 相似文献
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We give conditions for the linear span of the positive L-weakly compact (resp. M-weakly compact) operators to be a Banach lattice under the regular norm, for that Banach lattice to have an order continuous norm, to be an AL-space or an AM-space. 相似文献
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Maria Raquel Cavalcanti Inácio Maria de Fátima Vitória de Moura Kássio Michell Gomes de Lima 《Vibrational Spectroscopy》2011,57(2):342-345
This paper proposes a methodology for the classification and determination of total protein in milk powder using near infrared reflectance spectrometry (NIRS) and variable selection. Two brands of milk powder were acquired from three Brazilian cities (Natal-RN, Salvador-BA and Rio de Janeiro-RJ). The protein content of 38 samples was determined by the Kjeldahl method and NIRS analysis. Principal component regression (PCR) and partial least squares (PLS) multivariate calibrations were used to predict the total protein. Soft independent modeling of class analogy (SIMCA) was also used for full-spectrum classification, resulting in almost 100% classification accuracy, regardless of the significance level adopted for the F-test. Using this strategy, it was feasible to classify powder milk rapidly and nondestructively without the need for various analytical determinations. Concerning the multivariate calibration models, the results show that PCR, PLS and MLR-SPA models are good for predicting total protein in powder milk; the respective root mean square errors of prediction (RMSEP) were 0.28 (PCR), 0.25 (PLS), 0.11 wt% (MLR-SPA) with an average sample protein content of 8.1 wt%. The results obtained in this investigation suggest that the proposed methodology is a promising alternative for the determination of total protein in milk powder. 相似文献
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I. Ogawa T. Idehara S. Maekawa W. Kasparek G. F. Brand 《International Journal of Infrared and Millimeter Waves》1999,20(5):801-821
A compact system to convert gyrotron output into an intense gaussian beam has been designed by introducing an intermediate focusing element into the quasi-optical system. The design is significantly simplified by applying gaussian optics and confirmed by application of the Huygens equation. The beam quality is improved by truncating the sidelobes of the far-field. In spite of the beam truncation, only a small fraction (11 %) of the beam power is sacrificed. 相似文献
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We construct an analog of the Poincaré model for a quaternion hyperbolic space. 相似文献