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41.
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Helene Gunnarsson Mikael Rönnqvist Dick Carlsson 《Journal of Mathematical Modelling and Algorithms》2007,6(1):25-45
In this paper we consider integrated planning of transportation of raw material, production and distribution of products of the supply chain at Södra Cell AB, a major European pulp mill company. The strategic planning period is one year. Decisions included in the planning are transportation of raw materials from harvest areas to pulp mills, production mix and contents at pulp mills, distribution of pulp products from mills to customer via terminals or directly and selection of potential orders and their levels at customers. Distribution is carried out by three different transportation modes; vessels, trains and trucks. We propose a mathematical model for the entire supply chain which includes a large number of continuous variables and a set of binary variables to reflect decisions about product mix and order selection at customers. Five different alternatives regarding production mix in a case study carried out at Södra Cell are analyzed and evaluated. Each alternative describes which products will be produced at which pulp mills. 相似文献
43.
Dimensions and Lyapunov exponents from exchange rate series 总被引:2,自引:0,他引:2
Mikael Bask 《Chaos, solitons, and fractals》1996,7(12):2199-2214
Detecting the presence of deterministic chaos in economic time series is an important problem that may be solved by measuring the largest Lyapunov exponent. In this paper we present estimates of the largest Lyapunov exponent in daily data for the Swedish Krona vs Deutsche Mark, ECU, U.S. Dollar and Yen exchange rates. In order to estimate the dimension of the systems producing these exchange rate series, we also present estimates of the correlation dimension. We found indications of deterministic chaos in all exchange rate series. However, the estimates for the largest Lyapunov exponents are not reliable, except in the Swedish Krona-ECU case, because of the limited number of data points. In the Swedish Krona-ECU case, we found indications of a low-order chaotic dynamical system. 相似文献
44.
We prove that Gleason parts in uniform distinguished Fréchet algebras are open and closed in the weak topology. 相似文献
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Mikael Lindström 《manuscripta mathematica》1988,60(2):139-144
LetE be a locally convex space. We investigate under which conditions onE it is true that every holomorphic mapping fromE intoc
0 is compact. We show that Schwartzity ofE is a sufficient condition and also a necessary condition ifE is quasi-normable. 相似文献
49.
Elfinn Larsen Helge Egsgaard Umesh C. Pande Mikael Begtrup 《Journal of mass spectrometry : JMS》1983,18(2):52-56
Eleven halogen substituted 1-methyl-2-phenylpyrazolium bromides or chlorides were investigated by field desorption, field ionization, and electron impact mass spectrometry. Dealkylation was found to be the predominant thermal decomposition. An exchange between covalent and ionic halogen prior to dealkylation was observed and is discussed in detail. 相似文献
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