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排序方式: 共有1445条查询结果,搜索用时 15 毫秒
941.
Antti Perälä 《Archiv der Mathematik》2014,102(3):263-270
We consider the minimal Möbius invariant space of the unit disk with norm defined in terms of the second derivative. We obtain the best constant for the Bergman projection in this setting. We also show how this result generalizes to Bergman projections with respect to standard weights and beyond. 相似文献
942.
Yassin Yahya H. Jahre Magnus Kjeldsberg Per Gunnar Aunet Snorre Catthoor Francky 《Journal of Signal Processing Systems》2021,93(1):33-48
Journal of Signal Processing Systems - Stringent power budgets in battery powered platforms have led to the development of energy saving techniques such as Dynamic Voltage and Frequency scaling... 相似文献
943.
Letters in Mathematical Physics - We consider the Rosenzweig–Porter model $$H = V + sqrt{T}, varPhi $$ , where V is a $$N times N$$ diagonal matrix, $$varPhi $$ is drawn from the $$N... 相似文献
944.
When the electron density is a linear function of distance, it is known that the MSW equations for two neutrino species can
be solved in terms of known functions. It is shown here that more generally, for any number of neutrino species, these MSW
equations can be solved exactly in terms of single integrals. While these integrals cannot be expressed in terms of known
functions, some of their simple properties are obtained. Application to the solar neutrino problem is briefly discussed.
Received: 3 April 2000 / Accepted: 10 April 2000 相似文献
945.
946.
Per Hyltoft Petersen 《Accreditation and quality assurance》1999,4(9-10):406-409
A model for evaluation of analytical quality specifications for measurements performed on an ordinal scale is described. It is based on the assumption that the quantity, in principle, can be measured on a ratio (or difference) scale by other methods, but is performed by a cheap, simple and rapid method as 0 or 1 (minus or plus). It is not possible to estimate mean and standard deviations from an ordinal scale, so the measurements of 0 or 1 are characterized by the fraction of measured values of 1 for a certain concentration. For a series of increasing (known) concentrations of the quantity, the fractions of measured values of 1 are plotted on a probit scale. For a pregnancy test with measurements on an ordinal scale – measuring urine-human chorionic gonadotropin as minus or plus – allowable fractions of measured values of 1 are defined for the 'true' concentrations of 3 and 25 U/l based on clinical goals for early detection of pregnancy. 相似文献
947.
948.
949.
High pressure-frozen (HPF), freeze-fractured and freeze-dried rat cerebellum was analyzed with imaging TOF-SIMS equipped with a Bi-cluster ion source. Data were collected separately as spectra of high mass resolution m/Δm > 8000 and images of high lateral resolution <700 nm. Images were made showing the localization of the peaks m/z = 22.99, and m/z = 39.1.Topographical effects were noted due to the freeze fracture method. This effect was compensated by normalizing images of specific secondary ions to the intensity of total secondary ions and by making PCA analysis of the image. The results showed that potassium ions were localized in blood vessels and cortex cells and sodium ions were localized in blood vessels and cerebellar interstitial tissue and in the nuclei of some cells. The sodium ion concentration was found to be higher in blood vessels than in the interstitium. 相似文献
950.
The Cegrell classes with zero boundary data are defined by certain decreasing approximating sequences of functions with different
properties depending on the class in question. It is different for Cegrell classes which are given by a continuous function
f, these classes are defined by an inequality. It is proved in this article that it is possible to define the Cegrell classes
which are given by f in a similar manner as those classes with zero boundary data. An existence result for the Dirichlet problem for certain singular
measures is proved. The article ends with three applications. Results connected to convergence in capacity, subextension of
plurisubharmonic functions and integrability are proved. 相似文献