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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A necessary and sufficient criterion is presented under which the property of positivity carry over from the data set to rational quadratic spline interpolants. The criterion can always be satisfied if the occuring parameters are properly chosen. 相似文献
992.
The evolving tree-analysis and applications 总被引:2,自引:0,他引:2
In this paper, we enhance and analyze the Evolving Tree (ETree) data analysis algorithm. The suggested improvements aim to make the system perform better while still maintaining the simple nature of the basic algorithm. We also examine the system's behavior with many different kinds of tests, measurements and visualizations. We compare the ETree's performance against classical data analysis methods and very similar modern systems. We find that the ETree is a suitable method for unsupervised analysis of huge data sets. 相似文献
993.
J. W. Matousek 《Metallurgical and Materials Transactions B》2006,37(6):1085-1087
A thermodynamic analysis of a molten metal sulfide or oxide system begins with the equilibration of melts with a gas mixture
containing the active species, for example, H2S/H2 with sulfides and CO2/CO with oxides. The Gibbs-Duhem equation is then integrated to calculate the activities of the components of interest. Because
the sulfur pressures tend toward zero near the metal side of the binary and toward one bar at the metal sulfide side, integration
in these systems can be difficult. An alternative approach using negative mole fractions is described and applied to the silver-silver
sulfide system. 相似文献
994.
Equilibrium constants of pure hydrocarbons in different temperatures and pressures are necessary in most engineering calculations. A general formula has been developed to calculate equilibrium value for a group of hydrocarbons which have the general formula Cn H2n+2 and Cn H2n based on three parameters. This formula is a function of reduced temperature, reduced pressure, and an acentric factor. It is applied within a wide range of temperatures and pressures. As a result this technique is considered to be useful for the predication of K values of pure hydrocarbons depending on its reduced temperature, reduced pressure, and acentric factor. 相似文献
995.
In this work, we assessed the influence of coagulant residual activity and primary proteolysis on Cremoso Argentino cheese melting properties. For that purpose, we made Cremoso soft cheeses using different amounts of coagulant, and also obtained samples in which milk-clotting enzyme was inactivated. Primary proteolysis correlated with residual activity of coagulant in early stages of cheese ripening; however, it was similar in all cheeses after 30 days. The hydrolysis of caseins did not significantly affect the melting ability of the cheeses, expressed as the area increase after heating samples under standardized conditions. Samples with similar proximate composition showed some changes in meltability; those seemed related to pH evolution during ripening. 相似文献
996.
Jing Wang Walker D.M. Xiang Lu Majhi A. Kruseman B. Gronthoud G. Villagra L.E. van de Wiel P.J.A. Eichenberger S. 《Design & Test of Computers, IEEE》2007,24(3):226-234
Excessive power supply noise during test can cause overkill. This article discusses two models for supply noise in delay testing and their application to test compaction. The proposed noise models avoid complicated power network analysis, making them much faster than existing power noise analysis tools. can cause performance degradation and 相似文献
997.
A simple measurement method for the absolute Raman scattering cross-section of an optical fibre is presented. This method does not require a high power pump laser and it measures the fibre directly. It is also shown that the calculation of the cross-section depends on the fibre structure, such as its refractive index profile and the differential attenuation between the pump wavelength and Raman wavelength.<> 相似文献
998.
999.
1000.
Optical isomer separation by liquid chromatography 总被引:1,自引:0,他引:1
D W Armstrong 《Analytical chemistry》1987,59(2):84A-91A