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71.
矩阵平方根在数学的许多应用中起着重要的作用.本文研究M-矩阵平方根的计算问题,提出一种计算正则M-矩阵平方根的迭代方法.首先将这个问题转化为M-矩阵代数Riccati方程,进而提出一种有效的方法来求解这个特殊的MARE.理论分析表明,该方法在一定条件下是收敛的.数值实验表明该方法是可行的,且优于二项式迭代法. 相似文献
72.
73.
74.
Shinsaku Fujita 《Theoretical chemistry accounts》1990,78(1):45-63
Summary A coset representation (G(/G
i
)), which is defined algebraically by a coset decomposition of a finite groupG by its subgroupG
i
, is shown to be a method for the decomposition of a regular body into its point group orbits. This proof also shows that each member of theG(/G
i
) orbit belongs to theG
i
site-symmetry. In addition, a general equation concerning the multiplicities of such coset representations is derived and shown to involve Brester's equations and thek-value equations of framework groups as special cases. The relationship of the coset representation and the site-symmetry affords a general procedure for obtaining symmetry adapted functions. 相似文献
75.
Surface properties of the binary mixed systems of alkylpyridinium halides and sodium alkylsulfonates 总被引:1,自引:0,他引:1
Danuta Gralczyk Katarzyna H
c Pawe
Wydro 《Colloids and surfaces. A, Physicochemical and engineering aspects》2003,220(1-3):55-60
Surface properties of the binary mixed systems of decyl- and dodecylpyridinium chloride or bromide and sodium pentyl- and heptylsulfonate have been investigated. The surface tension of solutions of equimolar mixtures of surfactants and individual surfactants was measured, and the composition of mixed monolayers and surface interaction parameter β were calculated with the regular solution theory. Our results indicate that the properties of mixed films depend on both ionic strength and the kind of added inorganic electrolyte. With the increase of inorganic electrolyte concentration, the content of more surface active ions in the adsorption films enhances and is the highest in the presence of NaI and the smallest when solutions contain NaCl. Mutual interactions in mixed adsorbed films were found to be attractive. However, the strength of interaction weakens with the increase of ionic strength and depends on the kind of inorganic ions in the order: Cl−>Br−>I−. 相似文献
76.
In this article we prove a version of Noether's Theorem (of Calculus of Variations) which is valid for a general regular (compact) surface. As a special feature, the Lie group of transformations is allowed to act on the Cartesian product of the surface and the functional space. Additionally, we apply the Theorem to a problem in Classical Differential Geometry of surfaces. The given application is actually an example showing how Noether's Theorem can be used to construct invariant properties of the solutions to variational problems defined on surfaces, or equivalently, of the solutions to the associated Euler-Lagrange equations resulting from them. 相似文献
77.
This study has presented a performance investigation of an advanced tracked prime mover for the operation of agricultural goods and other operations on peat terrain. The maximum and continuous traction torque of the prime mover has been developed by designing an advanced controller for controlling the intelligent system. The prime mover’s mobility is studied with ultrasonic displacement sensor, torque transducer, National Instrument cRIO-9004 Compact-RIO Real-time Controller Unit (RCU), a National Instrument TPC 2106T Touch Panel Control (TPC), a Trimble AG132 GPS antenna and receiver unit, and a Dlink DIR-655 router. The fuzzy logic controller (FLC) has been equipped with the prime mover hydraulic system to increase the traction torque of the hydraulic motor when the prime mover’s sinkage is more than or equal to 70 mm. The prime mover’s design demonstrates good potential in traversing peat terrain as the measured tractive effort was found to be 48% of the vehicle’s gross weight while the recommended tractive effort is in the range of 30–36% of the vehicle’s gross weight. 相似文献
78.
B.T. Luke 《SAR and QSAR in environmental research》2013,24(1):41-57
While quantitative structure-activity relationships attempt to predict the numerical value of the activities, it is found that statistically good predictors do not always do a good job of qualitatively determining the activity. This study shows how Fuzzy classifiers can be used to generate Fuzzy structure-activity relationships which can more accurately determine whether or not a compound will be highly inactive, moderately inactive or active, or highly active. Four examples of these classifiers are presented and applied to a well-studied activity dataset. 相似文献
79.
《International Journal of Approximate Reasoning》2014,55(7):1606-1608
This note replies to comments made on our contribution to the Low Quality Data debate. 相似文献
80.
In this paper we present a new approach, based on the Nearest Interval Approximation Operator, for dealing with a multiobjective programming problem with fuzzy-valued objective functions. 相似文献