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51.
Roberto D. Galvão Luis Gonzalo Acosta Espejo Brian Boffey 《Annals of Operations Research》2006,143(1):31-44
A study has been carried out aimed at reducing perinatal mortality in the municipality of Rio de Janeiro through a better
distribution of health care facilities. The algorithmic aspects are detailed elsewhere and here the emphasis is on practical
issues and difficulties encountered.
A 3-level hierarchical model was developed. Both uncapacitated and capacitated versions are briefly described together with
some results based on actual data. The project brought to light many contradictions between OR theory and practice in developing
countries and, unfortunately, the models developed were not implemented by the municipality health authorities. Possible reasons
for this outcome are analysed. 相似文献
52.
53.
由于原子簇化合物在催化,生物活性,功能材料等方面所呈现的重要性,使其成为无机和物理化学最重要的研究领域之一。文章中和谱学方法对一些具有混配体的过渡金属簇合物的结构及其两者之间的关系进行. 相似文献
54.
François Métayer 《Archive for Mathematical Logic》1994,33(3):169-188
This work defines homology groups for proof-structures in multiplicative linear logic (see [Gir1], [Gir2], [Dan]). We will show that these groups characterize proof-nets among arbitrary proof-structures, thus obtaining a new correctness criterion and of course a new polynomial algorithm for testing correctness. This homology also bears information on sequentialization. An unexpected geometrical interpretation of the linear connectives is given in the last section. This paper exclusively focuses onabstract proof-structures, i.e. paired-graphs. The relation with actual proofs is investigated in [Gir1], [Gir2], [Dan], [Ret] and [Tro]. 相似文献
55.
The thermolysis of dicarbonylcyclopentadienyliron dimer in a sealed tube at 300°C has been reported to produce ferrocene, carbon monoxide, carbon dioxide, cyclopentadiene and elemental iron. We observe in addition to these products the production of biferrocene and elemental carbon. Thermolysis of carbonylcyclopentadienyliron tetramer (produced from the dimer by thermolysis in refluxing xylene) produces ferrocene, iron and carbon monoxidre; no biferrocene, carbon dioxide or elemental carbon are produced. A scheme is proposed to account for these products. 相似文献
56.
Numerical simulations are carried out to describe the dense zone of a spray where very little information is available, either from experimental or theoretical approaches. Interface tracking is ensured by the level set method and the ghost fluid method (GFM) is used to capture accurately sharp discontinuities for pressure, density and viscosity. The level set method is coupled with the VOF method for mass conservation. 相似文献
57.
François Bolley Arnaud Guillin Cédric Villani 《Probability Theory and Related Fields》2007,137(3-4):541-593
We establish quantitative concentration estimates for the empirical measure of many independent variables, in transportation
distances. As an application, we provide some error bounds for particle simulations in a model mean field problem. The tools
include coupling arguments, as well as regularity and moment estimates for solutions of certain diffusive partial differential
equations. 相似文献
58.
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60.
The complexification of a semi-algebraic set is the smallest complex algebraic set containing S. Let S be defined by s polynomials of degrees less than d. We prove that the geometric degree of the complexification is less than .
Received: 9 January 1997; in final form: 11 August 2000 / Published online: 17 May 2001 相似文献