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871.
The Fourier transform of orthogonal polynomials with respect to their own orthogonality measure defines the family of Fourier–Bessel
functions. We study the asymptotic behaviour of these functions and of their products, for large real values of the argument.
By employing a Mellin analysis we construct a general framework to exhibit the relation of the asymptotic decay laws to certain
dimensions of the orthogonality measure, that are defined via the divergence abscissas of suitable integrals. The unifying
r?le of Mellin transform techniques in deriving classical and new results is underlined.
Submitted: November 5, 2004. Accepted: January 6, 2006. 相似文献
872.
Faison P. Gibson 《Computational & Mathematical Organization Theory》2007,13(1):39-61
An important aspect of learning is the ability to transfer knowledge to new contexts. However, in dynamic decision tasks, such as bargaining, firefighting, and process control, where decision makers must make repeated decisions under time pressure and outcome feedback may relate to any of a number of decisions, such transfer has proven elusive. This paper proposes a two-stage connectionist model which hypothesizes that decision makers learn to identify categories of evidence requiring similar decisions as they perform in dynamic environments. The model suggests conditions under which decision makers will be able to use this ability to help them in novel situations. These predictions are compared against those of a one-stage decision model that does not learn evidence categories, as is common in many current theories of repeated decision making. Both models' predictions are then tested against the performance of decision makers in an Internet bargaining task. Both models correctly predict aspects of decision makers' learning under different interventions. The two-stage model provides closer fits to decision maker performance in a new, related bargaining task and accounts for important features of higher-performing decision makers' learning. Although frequently omitted in recent accounts of repeated decision making, the processes of evidence category formation described by the two-stage model appear critical in understanding the extent to which decision makers learn from feedback in dynamic tasks.
Faison (Bud) Gibson is an Assistant Professor at College of Business, Eastern Michigan University. He has extensive experience developing and empirically testing models of decision behavior in dynamic decision environments. 相似文献
873.
First order necessary conditions and duality results for general inexact nonlinear programming problems formulated in nonreflexive
spaces are obtained. The Dubovitskii–Milyutin approach is the main tool used. Particular cases of linear and convex programs
are also analyzed and some comments about a comparison of the obtained results with those existing in the literature are given. 相似文献
874.
Mike Wright 《The Journal of the Operational Research Society》1994,45(7):758-770
This paper concerns a computer system which has been devised to timetable the county cricket matches in England. The context of the work is discussed and the many constraints and objectives described. Details of the solution method are given; it involves tabu search with a form of diversification dependent on the solution subcosts as well as the overall cost. Experiments are described which suggest that this type of diversification may have wide applicability to large, complex, multi-objective combinatorial problems. 相似文献
875.
This paper outlines the results of a study undertaken to investigate the nature of Community Operational Research (COR). The objective was to contact the people involved in COR through a series of personal interviews and a questionnaire survey, in order to clarify many of the issues that have emerged within the profession relating to the practice of OR within the community and voluntary sector. A total of 20 individuals were successfully contacted, and they have been responsible for at least two-thirds of the projects in the COR area. 相似文献
876.
It is shown that the non-trivial cocycles on simple Lie algebras may be used to introduce antisymmetric multibrackets which
lead to higher-order Lie algebras, the definition of which is given. Their generalised Jacobi identities turn out to be satisfied
by the antisymmetric tensors (or higher-order “structure constants”) which characterise the Lie algebra cocycles. This analysis
allows us to present a classification of the higher-order simple Lie algebras as well as a constructive procedure for them.
Our results are synthesised by the introduction of a single, complete BRST operator associated with each simple algebra.
Received: 3 June 1996 / Accepted: 8 November 1996 相似文献
877.
Hakim Boumaza 《Mathematical Physics, Analysis and Geometry》2007,10(2):97-122
We study a continuous matrix-valued Anderson-type model. Both leading Lyapunov exponents of this model are proved to be positive
and distinct for all energies in (2, +∞) except those in a discrete set, which leads to absence of absolutely continuous spectrum
in (2, +∞). This result is an improvement of a previous result with Stolz. The methods, based upon a result by Breuillard
and Gelander on dense subgroups in semisimple Lie groups, and a criterion by Goldsheid and Margulis, allow for singular Bernoulli
distributions.
相似文献
878.
879.
In 1987 the Canadian Department of National Defence enunciated the Total Force concept. The Total Force is comprised of Regular and Reserve components. The intention is to make maximum use of the Reserve to reduce defence expenditures and at the same time to ensure that military capability remains adequate to support national policy objectives. This paper discusses some of the governing parameters that affect the modelling of the composition of the Total Force and analyses the mix of regular and reserve forces. The interplay between the key factors and their marginal costs will be stressed. The models are employed to study two units in the Canadian Forces, a maintenance support unit and a tactical unit with high operational activity cost. The lessons drawn from these studies are highlighted. 相似文献
880.
J. Y. Cavaillé R. Vassoille G. Thollet L. Rios C. Pichot 《Colloid and polymer science》1991,269(3):248-258
The emulsion polymerization process allows production of polymer particles with different structural morphologies. Films obtained after coalescence keep some memory of this morphology, but large modifications can occur during coalescence. In the present case, one of the polymers, polystyrene (PS), exhibits a glass temperature (Tg) much higher than the filmification temperature (close to room temperature), while the other one, poly(butyl acrylate) (PBA), has a much lowerTg. Furthermore, it is well known that dynamic mechanical measurements can be very helpful in providing information on the morphology of polymer materials, i.e., on geometrical and topological arrangement of homopolymer domains. At first, this method was used for comparison of two types of films: i) the first one obtained from structured-core (PS)-shell (PBA) particles, ii) the second one obtained from a blend of homopolymer particles (PS and PBA). It appears that the expected core-shell particles lost their geometric structure in the second film. Second, comparison of the predicted dynamic modulus and experimental data shows that i) strong interactions exist between PS nodules unless their coalescence has occured, leading to an abnormally high modulus at room temperature, ii) after achieving their coalescence, PS forms a more or less continuous phase. Both phenomena strongly depend on the particle size and their respective volume fractions. 相似文献