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1.
Vladimir Katkovnik Jaakko Astola Karen Egiazarian 《IEEE transactions on image processing》2008,17(6):833-846
The local polynomial approximation (LPA) is a nonparametric regression technique with pointwise estimation in a sliding window. We apply the LPA of the argument of cos and sin in order to estimate the absolute phase from noisy wrapped phase data. Using the intersection of confidence interval (HCI) algorithm, the window size is selected as adaptive pointwise varying. This adaptation gives the phase estimate with the accuracy close to optimal in the mean squared sense. For calculations, we use a Gauss-Newton recursive procedure initiated by the phase estimates obtained for the neighboring points. It enables tracking properties of the algorithm and its ability to go beyond the principal interval [-pi, pi] and to reconstruct the absolute phase from wrapped phase observations even when the magnitude of the phase difference takes quite large values. The algorithm demonstrates a very good accuracy of the phase reconstruction which on many occasion overcomes the accuracy of the state-of-the-art algorithms developed for noisy phase unwrap. The theoretical analysis produced for the accuracy of the pointwise estimates is used for justification of the HCI adaptation algorithm. 相似文献
2.
Amanda LaCoste Karen M. Schaich David Zumbrunnen Kit L. Yam 《Packaging Technology and Science》2005,18(2):77-87
Researchers from Rutgers University and Clemson University have collaborated to develop a concept of using smart blending to generate functional packaging films for the controlled release of active compounds such as antimicrobials, antioxidants and flavour compounds to extend the shelf‐life of food. In this paper, literature results are reviewed to justify the significance of controlled release packaging (CRP) and the research gaps for further development are identified. A major research gap is the lack of packaging materials that can provide the release of active compounds at rates suitable for a wide range of food packaging applications. Smart blending is a promising technology for bridging this research gap. To fully realize the potentials of smart blending, a systematic approach for developing CRP using smart blending is also presented. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Ma Shizhou Beazley Karen F. Nussey Patrick Greene Christopher S. 《Water Resources Management》2021,35(14):4825-4840
Water Resources Management - The Active River Area (ARA) is a spatial approach for identifying the extent of functional riparian area. Given known limitations in terms of input elevation data... 相似文献
6.
Ghukasyan Tsolak Yeshilbashyan Yeva Avetisyan Karen 《Programming and Computer Software》2021,47(1):56-66
Programming and Computer Software - In this work, we present purely subword-based alternatives to fastText word embedding algorithm The alternatives are modifications of the original fastText... 相似文献
7.
Karen A. Lee Margaret A. Frerking 《Journal of Infrared, Millimeter and Terahertz Waves》1989,10(7):789-802
A quasi-optical reflection cavity intended to be used as the resonant load of a submillimeter wavelength oscillator has been designed, constructed, and tested. The resonator consists of three elements in cascade: a high Q, high finesse folded Fabry-Perot resonator, a lower Q, low finesse Fabry-Perot resonator, and a Littrow mounted diffraction grating. The resonator exhibits a Q of 6600 and 2.5 dB of loss at 63 GHz. The design can be scaled to 1 THz, where waveguide structures become impractical, to serve as the resonator for high frequency quantum well resonant tunneling device oscillators. 相似文献
8.
Karen Goodnough 《Canadian Journal of Science, Mathematics, & Technology Education》2013,13(3):289-306
Abstract: In this self‐study, the author gained in‐depth understanding of how to plan and implement problem‐based learning (PBL), a student‐centred approach to teaching and learning that is driven by messy, open‐ended problems. This paper focuses primarily on the issues and concerns that arose as she developed and implemented a modified form of traditional PBL (Barrows, 1996) in large, pre‐service science‐teacher education classes. To view the research from many perspectives, a variety of data collection methods and sources were used, including field notes, semi‐structured interviews, student‐generated documents, and student journals. The outcomes of this study describe challenges (problem development, facilitation of groups, and assessment) encountered by the author as she planned for and implemented PBL. Furthermore, changes in the author's classroom practice, the connection between these changes and constructivist learning principles, and implications for science‐teacher education are addressed. 相似文献
9.
George A. Sorial Albert D. Venosa Karen M. Koran Edith Holder Dennis W. King 《Canadian Metallurgical Quarterly》2004,130(10):1085-1093
The current U.S. Environmental Protection Agency (EPA) protocol for testing the effectiveness of dispersants for use in treating oil spills on the open water, the swirling flask test (SFT), has been found to give widely varying results in the hands of different testing laboratories. Part I addressed the sources of the ambiguities in the EPA SFT and the development of a new test referred to as the baffled flask test (BFT). In this part of the series, further experiments were conducted for estimating the repeatability of three operators in determining the effectiveness of 18 dispersants by both the EPA SFT and the BFT methods. Overall statistical analysis of the results indicated that the coefficient of variation by the BFT was only 7.8% compared to 21.9% for the EPA SFT. The mean percent effectiveness of the EPA SFT was only 19.7% as compared to 64.6% for the BFT. Proposed selection criteria for screening of dispersants for listing on the National Contingency Plan Product Schedule have been developed. 相似文献