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991.
The characteristics of a cutting stock problem for large sections in the iron and steel industries are as follows:(1) There is a variety of criterions such as maximizing yield and increasing effeciency of production lines. (2) A cutting stock problem is accompanied by an optimal stock selection problem. A two-phase algorithm is developed, using an heuristic method. This algorithm gives nearly optimal solutions in real time. It is applied to both batch-solving and on-line solving of one-dimensional cutting of large section. The new algorithm has played an important role in a large-section production system to increase the yield by approximately 2.5%. 相似文献
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This paper presents a theorem concerning a matroid with the parity condition. The theorem provides matroid generalizations of graph-theoretic results of Lewin and Gallai. 相似文献
994.
Applying a phase transformation and taking an average over atomic scale variations, we get a reduced Hamiltonian of the Peierls-Fröhlich system, which is a coupled system of electrons and phase fluctuations of CDW essentially. Interchain coupling is assumed to be solely due to lattice vibrations. Three dimensional CDW-ordering temperature is obtained. 相似文献
995.
Yoshinori Kadoma Akihiko Ueno Kenji Takeda Keikichi Uno Yoshio Iwakura 《Journal of polymer science. Part A, Polymer chemistry》1975,13(7):1545-1553
Poly(γ-cinnamyl L -glutamate) was irradiated in the presence and absence of benzophenone in dichloroethane. The irradiated polymers were analyzed by gas chromatography after hydrolysis. It was possible to assign the transformation in the presence of benzophenone to trans-cis photoisomerization by comparing the effects with those observed for a model compound cinnamyl acetate. The equilibrium composition of cis and trans isomers in the photostationary state was similar for the model compound and the polypeptide. Photoisomerization was found to be accompanied by marked side reactions for the direct irradiation. Circular dichroism spectra were empolyed to study the structure, and no changes in the structure were found for the irradiated polymers. 相似文献
996.
Summary The electrical conductivity of brain lesions varies with pathological situations such as edema and calcification. The effect
of the tissue inhomogeneities of brain lesions on spatial distributions of electrical potentials and magnetic fields over
the surface of the head was studied by means of a computer simulation.
Paper presented at the ?IV International Workshop on Biomagnetism?, held in Rome, September 14–16, 1982. 相似文献
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