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101.
Ricardo P. Beausoleil Gulnara Baldoquin Rodolfo A. Montejo 《Annals of Operations Research》2008,157(1):105-133
This paper deals with a multiobjective combinatorial optimization problem called Extended Knapsack Problem. By applying multi-start
search and path relinking we rapidly guide the search toward the most balanced zone of the Pareto-optimal front. The Pareto
relation is applied in order to designate a subset of the best generated solutions to be the current efficient set of solutions.
The max-min criterion with the Hamming distance is used as a measure of dissimilarity in order to find diverse solutions to
be combined. The performance of our approach is compared with several state-of-the-art MOEAs for a suite test problems taken
from the literature. 相似文献
102.
Vladimir S. Lerner 《Journal of Mathematical Analysis and Applications》2007,335(2):1461-1481
Using the probabilistic evaluation of the Marcovian diffusion process by a functional of action, the paper introduces a dynamic approximation of a random information functional defined on the process trajectories and determined by the parameters of a controlled stochastic equation. The developed mathematical formalism is aimed toward a dynamic modeling of a random object. 相似文献
103.
A path cover of a graph G=(V,E) is a family of vertex-disjoint paths that covers all vertices in V. Given a graph G, the path cover problem is to find a path cover of minimum cardinality. This paper presents a simple O(n)-time approximation algorithm for the path cover problem on circular-arc graphs given a set of n arcs with endpoints sorted. The cardinality of the path cover found by the approximation algorithm is at most one more than the optimal one. By using the result, we reduce the path cover problem on circular-arc graphs to the Hamiltonian cycle and Hamiltonian path problems on the same class of graphs in O(n) time. Hence the complexity of the path cover problem on circular-arc graphs is the same as those of the Hamiltonian cycle and Hamiltonian path problems on circular-arc graphs. 相似文献
104.
路径积分方法计算聚合物溶液热力学性质 总被引:1,自引:0,他引:1
提出了把聚合物溶液的自由能分解为 3部分 ,平动部分、构象部分和热修正项部分 .其中后两部分具有相对于链段的可加性 ,在引入了“有效浓度”的概念后可以用路径积分方法计算 .当采用体积分数代替有效浓度时 ,就回到了李晓毅和赵得禄的溶液理论 .还利用本理论研究了不同分子量聚苯乙烯 环己烷体系的相分离曲线 ,同Flory Huggins(FH)理论相比 ,大大提高了同实验数据的符合程度 相似文献
105.
Vyjayanthi Chari 《Advances in Mathematics》2007,216(2):811-840
We study the category of graded finite-dimensional representations of the polynomial current algebra associated to a simple Lie algebra. We prove that the category has enough injectives and compute the graded character of the injective envelopes of the simple objects as well as extensions between simple objects. The simple objects in the category are parametrized by the affine weight lattice. We show that with respect to a suitable refinement of the standard ordering on the affine weight lattice the category is highest weight. We compute the Ext quiver of the algebra of endomorphisms of the injective cogenerator of the subcategory associated to an interval closed finite subset of the weight lattice. Finally, we prove that there is a large number of interesting quivers of finite, affine and star-shaped type, as well as tame quasi-hereditary algebras, that arise from our study. 相似文献
106.
针对无机化学传统教学模式的不足,构建了无机化学微信平台。介绍了构建平台必需的微信公众号和微信群的建立过程和方法。分析了无机化学微信平台在教学中的实践效果,弥补了传统教学中的不足。讨论了无机化学微信平台的积极作用,提高了教师教学水平和学生的学习能力,达到了师生双赢的目的。 相似文献
107.
108.
Xin ZHAO 《数学年刊B辑(英文版)》2022,43(2):265-280
The authors give the condition that the Bergman kernel function on the first type of Cartan-Hartogs domain exists zeros. If the Bergman kernel function of this type of domain has zeros, the zero set is composed of several path-connected branches, and there exists a continuous curve to connect any two points in the non-zero set. 相似文献
109.
A thermoanalyser for studies in an atmosphere of a strong fluorinating agent has been designed. A methodology for simultaneously obtaining DTA and TG/DTG curves of physicochemical processes over a wide range of temperatures in environments of gaseous fluorine, hydrogen fluoride and chlorine trifluoride, as well as under vacuum and hydrogen, has been developed. The construction of the thermoanalyser is described in detail. To illustrate the capabilities of the thermoanalyser a study of the thermal behaviour of M2IrCl6 complexes with gaseous fluorine is presented. 相似文献
110.
Josef Kratochvíla Bedřich Friedecký Marek Budina Ilona Šperlingová 《Accreditation and quality assurance》2007,12(3-4):146-150
In this paper, the creation of a certified reference material for urinary creatinine is described. We used the Jaffe method
and HPLC method for establishment of the certified value. Homogeneity tests are also described. We obtained material with
sufficient homogeneity, stability, and with certified value (expanded uncertainty, k=2 for CI 95%) (7.77±0.27) mmol·L−1. This material was consequently used for the interlaboratory comparison (EQA Czech Republic for clinical chemistry). Twenty-nine
percent of the participants obtained measurement results within the interval of the certified value ± expanded uncertainty,
while 85% of the participants obtained values inside the interval of the certified value ± target measurement uncertainty.
Direct use of the certified reference materials for method evaluation in EQA programs means a significant advance for monitoring
and documentation traceability of results in routine measurements. 相似文献