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151.
152.
153.
Rudolf Felix 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2008,12(2):129-135
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
154.
155.
Sun-Yuan Hsieh 《The Journal of supercomputing》2007,39(1):39-57
A graph is distance-hereditary if the distance stays the same between any of two vertices in every connected induced subgraph containing both. Two well-known
classes of graphs, trees and cographs, both belong to distance-hereditary graphs. In this paper, we first show that the perfect
domination problem can be solved in sequential linear-time on distance-hereditary graphs. By sketching some regular property
of the problem, we also show that it can be easily parallelized on distance-hereditary graphs. 相似文献
156.
Wenying Wei Zhen Wang Yanhua Yin Jinyu Han Wen Xu 《Korean Journal of Chemical Engineering》2008,25(3):562-567
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
157.
158.
159.
Sangho Kim Young-Roc Im Sunghak Lee Hu-Chul Lee Sung-Joon Kim Jun Hwa Hong 《Metallurgical and Materials Transactions A》2004,35(7):2027-2037
This study is concerned with the effects of alloying elements on fracture toughness in the transition temperature region of
base metals and heat-affected zones (HAZs) of Mn-Mo-Ni low-alloy steels. Three kinds of steels whose compositions were varied
from the composition specification of SA 508 steel (grade 3) were fabricated by vacuum-induction melting and heat treatment,
and their fracture toughness was examined using an ASTM E1921 standard test method. In the steels that have decreased C and
increased Mo and Ni content, the number of fine M2C carbides was greatly increased and the number of coarse M3C carbides was decreased, thereby leading to the simultaneous improvement of tensile properties and fracture toughness. Brittle
martensite-austenite (M-A) constituents were also formed in these steels during cooling, but did not deteriorate fracture
toughness because they were decomposed to ferrite and fine carbides after tempering. Their simulated HAZs also had sufficient
impact toughness after postweld heat treatment. These findings indicated that the reduction in C content to inhibit the formation
of coarse cementite and to improve toughness and the increase in Mo and Ni to prevent the reduction in hardenability and to
precipitate fine M2C carbides were useful ways to improve simultaneously the tensile and fracture properties of the HAZs as well as the base
metals. 相似文献
160.
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