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排序方式: 共有2239条查询结果,搜索用时 31 毫秒
1.
Saleh Z. M. Nasser H. Özkol E. Günöven M. Abak K. Canli S. Bek A. Turan R. 《Journal of nanoparticle research》2015,17(10):1-12
Journal of Nanoparticle Research - Plasmonic interfaces consisting of silver nanoparticles of different sizes (50–100&;nbsp;nm) have been processed by the self-assembled dewetting... 相似文献
2.
Methylcyanide, CH3CN, is an important interstellar species, and therefore the accurate knowledge of precise rest frequencies for rotational transitions as well as ground-state rotational and hyperfine constants is needed. In this work the hyperfine structure of the millimeter- and submillimeter-wave spectra of CH3CN has been further investigated. In addition, accurate THz measurements have been carried out for the first time. Consequently, the present investigation allowed us to provide the most accurate ground state rotational and hyperfine parameters known at the moment for CH3C14N. To resolve the hyperfine structure of the rotational transitions observed, the Lamb-dip technique has been exploited. Both frequency-modulated and video-type detections have been employed. 相似文献
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Gabriele Bonanno 《Journal of Global Optimization》1998,12(1):101-104
In this note we introduce a suitable class of functionals, including the class of integral functionals, and prove that any (strict) local minimum of a functional of this class, defined on a decomposable space, is a (strict) global minimum. So, the recent result obtained by Giner in [1] is specified and extended. 相似文献
5.
Stephan Dahlke Gabriele Steidl Gerd Teschke 《Journal of Fourier Analysis and Applications》2004,10(5):507-539
This article is concerned with frame constructions on domains and manifolds. The
starting point is a unitary group representation which is square integrable modulo a suitable
subgroup and therefore gives rise to a generalized continuous wavelet transform. Then generalized
coorbit spaces can be defined by collecting all functions for which this wavelet transform
is contained in a weighted Lp-space. Moreover, we show that a judicious discretization of the
representation leads to an atomic decomposition and to Banach frames for these coorbit spaces. 相似文献
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Estimating market shares in each market segment using the information entropy concept 总被引:3,自引:0,他引:3
Sales data of a certain product for the various competitors are usually available at the aggregate level. However these data give no clue to the heterogeneities in the sales pattern across different market segments. Heterogeneities are caused by different purchasing behavior in each market segment; as a purchaser in a segment will be attracted to the attributes of the product most important to that segment. This concept can be formalized via a simple attraction model that utilizes an elasticity measure for each quality or price attribute [G.S. Carpenter, L.G. Cooper, D.M. Hanssens, D.F. Midgley, Modeling asymmetric competition, Marketing Science 7 (4) (1998) 393–412]. Assessment of these elasticities is not difficult since customer response – in each market segment – to perception of quality and price is tracked by most firms [J. Ross, D. Georgoff, A survey of productive and quality issues in manufacturing. The state of the industry, Industrial Management 3 (5) (1991) 22–25]. This paper attempts to formulate a generic framework based on the information entropy concept that utilizes such an attraction model to estimate competitors’ sales in each market segment. 相似文献
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Giovanni Cerioni Costantino Floris Giaime Marongiu Gabriele Navarra Francesca Sotgiu 《Journal of heterocyclic chemistry》1994,31(5):1151-1155
1-5-benzoxathiepine compounds are a novel class of heterocyclic rings that present interesting properties as central nervous system depressants. With the aim to contribute to the elucidation of the structure-activity relationship of this class of compounds we report a structural study of the 3-hydroxy-1,5-benzoxathiepine both in solution and in the solid state. Studies by dynamic 13C-nmr in solution show that three conformations are possible for the oxathiepin ring. A unique chair conformation characterizes the atoms in the oxathiepine ring of the crystallized molecule. The crystal structure was solved by direct methods. Values of bond distances and angles are within the expected range. 相似文献