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91.
Real world applications of a decision model of relationships between goals based on fuzzy relations are presented. In contrast to other approaches the relationships between decision goals or criteria for each decision situation are represented and calculated explicitly. The application fields are decision making for financial services and optimization of production sequences in car manufacturing.  相似文献   
92.
93.
Composition Group Vector Space (CGVS) method for estimating melting and boiling point T m , T b of organic compound has been proposed, and the principle of this method has been elucidated. The models for estimating T m , T b have been established and the numerical values of relative parameters have been presented. The average percentage deviations of T m , T b estimation are 7.53 and 1.58, respectively, which show that the present method demonstrates significant improvement in applicability to predict the above properties, compared to conventional group methods.  相似文献   
94.
95.
This article proposes an approach for investigating the exponential stability of a nonlinear interval dynamical system with the nonlinearity of a quadratic type on the basis of the Lyapunov’s direct method. It also constructs an inner estimate of the attraction domain to the origin for the system under consideration.  相似文献   
96.
Summary  Well-defined water-soluble poly(styrenesulfonate)-b-poly(ethylene glycol)-b- poly(styrenesulfonate) (PSS-b-PEG-b-PSS) triblock copolymers with narrow molecular weight distribution (1.29 < Mw/Mn < 1.36) were synthesized in aqueous solution at 70 oC via reversible addition-fragmentation chain transfer (RAFT) polymerization. The complex formed by the PSS-b-PEG-b-PSS triblock copolymer coordinated with aluminum ion was investigated with turbidimetry, dynamic light scattering (DSL), zeta-potential, and transmission electron microscopy (TEM). The aggregation formation was based on the neutralization of the SO3- groups in the PSS blocks with Al3+ ions. The appearance, size and stability of the PSS-b-PEG-b-PSS/Al3+ aggregates were controlled by varying the PSS block length and degree of neutralization (DN). At DN = 0.33, where the PSS-b-PEG-b-PSS copolymer was completely neutralized with Al3+, the aggregate size increased with increasing PSS block length. The transition from the shrinking coil of small size to the interchain aggregates of large size was found at DN of about 0.33.  相似文献   
97.
Modellierung in der Lehre an Hochschulen: Thesen und Erfahrungen   总被引:1,自引:1,他引:0  
Zusammenfassung  Nicht erst seit Modellierung zum Modewort geworden ist, ist Modellierung ein wichtiges Thema in der Informatikausbildung. Dieser Beitrag beleuchtet in zw?lf Thesen das Warum, Was, Wie viel, Wo, Wann und Wie von Modellierung in der Lehre im Rahmen informatikbezogener Studieng?nge. Die Thesen basieren auf der Erfahrung des Verfassers mit einer seit über zehn Jahren gehaltenen Modellierungsvorlesung an der Universit?t Zürich sowie dem Gedankenaustausch mit anderen Hochschullehrerinnen und -lehrern im Rahmen der GI-Workshopreihe ,,Modellierung“. Zus?tzlich liefert eine Befragung von Absolventinnen und Absolventen an der Universit?t Zürich empirische Evidenz für eine Reihe der Thesen.  相似文献   
98.
This paper will describe the solid oxide membrane (SOM) process as it applies to the energy-efficient and environmentally sound production of magnesium from magnesium oxide. Also, it will describe the challenges encountered while using this process for the production of transition metals like titanium from its higher oxides. Finally, a novel magnesiothermic SOM process will be proposed that can enable production of transition metals from its higher oxides.  相似文献   
99.
This paper reports an alternative method for the growth of GaN epitaxial layer on (0001) Al2O3 substrate by hot-wall vapor phase epitaxy technique. Tris (N,N-dimethyldithiocarbamato)-gallium (III), Ga(mDTC)3 was introduced as a precursor material for the seed layer formation in the growth of GaN. Optimal growth conditions with seed layers formed by the Ga(mDTC)3 concentration of 0.047 mol/L were identified: Growth temperature was found to be 850 °C, and optimal distance between the reactant outlet and substrate was determined to be 12.5 cm. Characterization results showed that this growth method produce high-crystallinity GaN epitaxial layers at a relatively lower growth temperature compared to the existing growth techniques and simplify the growth process.  相似文献   
100.
The rate of filtration and the water content of cake are influenced by the existence of a dense skin in a highly compressible cake. The phenomenon of the dense skin has been rarely studied, and its existence has not been verified experimentally. In this study, the porosity variation in a very compressible cake is measured by using a new experimental apparatus, and with this the existence of dense skin has been established experimentally. ‘Unified theory on solid-liquid separation’, a recently developed theory, is utilized for calculating the porosity variation in a very compressible cake.  相似文献   
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