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21.
In this paper we face the problem of stowing a containership, referred to as the Master Bay Plan Problem (MBPP); this problem
is difficult to solve due to its combinatorial nature and the constraints related to both the ship and the containers. We
present a decomposition approach that allows us to assign a priori the bays of a containership to the set of containers to
be loaded according to their final destination, such that different portions of the ship are independently considered for
the stowage. Then, we find the optimal solution of each subset of bays by using a 0/1 Linear Programming model. Finally, we
check the global ship stability of the overall stowage plan and look for its feasibility by using an exchange algorithm which
is based on local search techniques. The validation of the proposed approach is performed with some real life test cases.
This work has been developed within the research area: “The harbour as a logistic node” of the Italian Centre of Excellence
on Integrated Logistics (CIELI) of the University of Genoa, Italy 相似文献
22.
This paper addresses the problem of determining stowage plans for containers in a ship, that is the so-called master bay plan problem (MBPP). 相似文献
23.
The “true detection limit” CL,true was measured by a method proposed by Boumans et al. for 10 prominent lines of La, Ce, Pr, Nd and Sm, the most abundant rare
earth elements (REEs) in geological samples. It is demonstrated how spectral interferences can increase of CL,true. The spectra were excited in an argon arc plasma jet with evaporation powders of five complex natural samples. The data show
that there is a significant increase of CL,true in real samples containing large concentrations of such elements as Ti, Zr, Cr, Nb, Ta and REEs emitting complex spectra.
Received: 17 June 1997 / Revised: 20 October 1997 / Accepted: 26 October 1997 相似文献
24.
25.
Summary In the present work we extent the results in [RS] on CHIP, i.e. Cardinal Hermite Interpolation by the span of translates of directional derivatives of a box spline. These directional derivatives are that ones which define the type of the Hermite Interpolation. We admit here several (linearly independent) directions with multiplicities instead of one direction as in [RS]. Under the same assumptions on the smoothness of the box spline and its defining matrixT we can prove as in [RS]: CHIP has a system of fundamental solutions which are inL
L
2 together with its directional derivatives mentioned above. Moreover, for data sequences inl
p
(
d
), 1p2, there is a spline function inL
p, 1/p+1/p=1, which solves CHIP.Research supported in part by NSERC Canada under Grant # A7687. This research was completed while this author was supported by a grant from the Deutscher Akademischer Austauschdienst 相似文献
26.
Elena Prestini 《Monatshefte für Mathematik》1988,105(3):207-216
LetfL
p(
n
),n2, be a radial function and letS
Rf be the spherical partial sums operator. We prove that if
thenS
Rf(x)f(x) a.e. asR. The result is false for
and
\frac{{2n}}{{n + 1}}$$
" align="middle" border="0">
.Partially supported by M.P.I. 相似文献
27.
Thermal response of metals to ultrashort-pulse laser excitation 总被引:1,自引:0,他引:1
28.
29.
Strategically designed sample composition (SSC) is a new technique that decreases the number of analytical determinations needed in routine screening to as few as the number of original sample specimens while providing information that is specific to them. Although this new technique has been applied to environmental studies, this paper describes its first application to food safety studies. Contamination of milk samples with polychlorinated biphenyls (PCBs) was chosen as a case study to show the usefulness and potential of the SSC technique with a fast analytical procedure that involves saponification of the samples and solid-phase microextraction of the PCBs. A total of 20 sample specimens can be analyzed in 11 determinations with excellent predictions of the positive samples and the concentration levels of the contaminants. The robustness of the strategy was investigated and demonstrated. 相似文献
30.
[formula: see text] The appended sugars in macrolide antibiotics are indispensable to the biological activities of these important drugs. In an effort to generate a set of novel macrolide derivatives, we have created a new analogue of methymycin and neomethymycin, antibiotics produced by Streptomyces venezuelae. This analogue 15 carrying a different sugar, D-quinovose, instead of D-desosamine, was constructed by taking advantage of targeted gene deletion combined with a specific pathway-independent C-3 reduction capability of the wild type S. venezuelae. 相似文献