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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.
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
25.
G. V. Gedrovich Ya. L. Kogan N. D. Kushch M. I. Rudakova V. I. Savchenko I. G. Shunina 《Russian Chemical Bulletin》1991,40(1):194-196
The feasibility of obtaining electrically conducting and active films by the electropolymerization of aniline in butylpyridinium tetrachloroaluminate or hexachlorodialuminate as the medium has been demonstrated. Identical voltamperometric characteristics with a potential peak of 0.5 V were found in these films and the compound formed upon the electrochemical polymerization of aniline in 20% hydrochloric acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 212–214, January, 1991. 相似文献
26.
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
27.
28.
Quantum mechanical and quantum mechanical/molecular mechanical calculations in conjunction with continuum solvation models have been used to analyze CH-pi interactions in model systems of aryl- and alkyl-aromatic interactions, as well as in a model folding system designed to study those interactions. High level calculations reproduced accurately the interaction of CH-pi interactions in both alkyl- and aryl-based model systems. Dispersion effects dominate the interaction, but the electrostatics term is also relevant for aryl CH-pi interactions. Theoretical calculations were also used to examine the influence of CH-pi interactions in determining the conformational flexibility of folding models. Finally, a critical comparison of the results obtained from high level calculations on model systems and the experimental data derived for folding models in apolar solvents was carried out, which allowed us to reconcile the apparent discrepancy found between both data. 相似文献
29.
Attilio Citterio Massimo Ramperti Elena Vismara 《Journal of heterocyclic chemistry》1981,18(4):763-766
Free-radical decomposition of diazonium salts catalyzed by titanous or titanous and ferrous salts in the presence of β-substituted α,β-unsaturated carbonyl compounds leads to 1,4-diarylpyrazole derivatives. The reaction occurs via an intermediate azo compound ( 1 ), which can be reduced by the metal salt or can be isolated and hydrogenated to pyrazole derivatives. 相似文献
30.
Intramolecular cyclization of 1-amino-3-phenacyl-4-carbohydrazido-1,2,3-triazolium-5-olates has been shown to take place via selective interaction of the carbonyl group with the terminal amino function of the hydrazido group to form a 1,2,5-triazepine ring. Minor products, resulting from the interaction of the α-nitrogen atom of the hydrazido group with the carbonyl function, having a N-amino-pyridazine structure were also detected and isolated. A general method for the synthesis of novel mesoionic 2-amino-7-aryl-4-oxo-2,4,5,8-tetrahydro[1,2,3]triazolo[5,1-d][1,2,5]triazepin-9-ium-3-olates was developed. 相似文献