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991.
K. A. Burlov-Vasil'ev I. E. Vasil'eva E. A. Gurtovenko Yu. B. Matveev 《Radiophysics and Quantum Electronics》1996,39(10):887-892
This paper presents the Big Horizonal Solar Telescope of the Main Astronomical Observatory of the Ukrainian National Academy of Sciences installed at the Peak Terskol high-altitude station near Elbrus (the main mirror diameter is 650 mm and the focal length is 17.5 m). The telescope is equipped with a five-camera spectrograph intended for photographic spectral observations of active regions in the solar atmosphere and photoelectric measurements of the solar spectra with high spectral and spatial resolution. The observation procedure is described, and the results of the quality analysis of the recorded spectra and of the early measurements are presented.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 39, No. 10, pp. 1326–1333, October, 1996.The authors wish to express their gratitude to C.I.Gandzha, V.V.Kul'beda, and Yu. M. Gavrilyuk from the Solar Physics Department of the PAO of the Ukrainian NAS and to the Board of Directors of the Observatory and of the High-Altitude Station for help in the development of the instrument.This paper is dedicated to the memory of E. A. Gurtovenko, D.Sc. in Phys. and Math., who initiated the installation of the telescope at Peak Terskol and who was the leader, an executor, and an observer in this project. 相似文献
992.
Gur Mosheiov 《The Journal of the Operational Research Society》1996,47(9):1184-1191
We study a problem of scheduling deteriorating jobs, i.e. jobs whose processing times are an increasing function of their starting times. We consider the case of a single machine and linear job-independent deterioration. The objective is to minimize the sum of weighted completion times, with weights proportional to the basic processing times. The optimal schedule is shown to be Λ-shaped, i.e. the sequence of the basic processing times has a single local maximum. Moreover, we show that the problem is solved in O(N log N) time. In the last section we test heuristics for the case of general weights. 相似文献
993.
Yu Chen 《Transactions of the American Mathematical Society》1996,348(9):3733-3743
We demonstrate a one to one correspondence between the irreducible projective representations of an affine Kac-Moody group and those of the related loop group, which leads to the results that every non-trivial representation of an affine Kac-Moody group must have its degree greater than or equal to the rank of the group and that the equivalence appears if and only if the group is of type for some . Moreover the characteristics of the base fields for the non-trivial representations are found being always zero.
994.
995.
V. K. Turchaninov G. V. Dolgushin M. Yu. Dmitrichenko L. I. Larina 《Russian Chemical Bulletin》1996,45(4):781-785
The -orbital structure of the monomeric form of the 2,2,4,6-tetrachloro-2,2-dihydro-1,5,2-diazaphosphorinine has been studied by photoelectron spectroscopy and using quantum-chemical calculations by the semiempirical AM1 method. It has been concluded that the electronic and energy characteristics of four higher -MOs (frontier and three next orbitals) of this compound may be interpreted in terms of semipolar bonds formed by three atoms (C, P, and N). For describing two low-lying -MOs of the 4,5-phosphorine studied, it is necessary to take into account the --interaction.For Part 8, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 827–831, April, 1996. 相似文献
996.
Ya. S. Kayukov O. E. Nasakin Ya. G. Urman V. N. Khrustalev V. N. Nesterov M. Yu. Antipin A. N. Lyushchikov P. M. Lukin 《Chemistry of Heterocyclic Compounds》1996,32(10):1200-1212
2-Aryl-1,2,3,4-tetrahydropyridine-3,3,4,4,-tetracarbonitriles and 1,3,5-triaryl-9-oxo-1,2,3,4b,5,6,8a,9-octahydropyrido[3,4:3,4]pyrrolo[1,2-a][1,3,5]triazine-4b,8a-dicarbonitriles are formed by the reaction of 4-oxoalkane-1,1,2,2-tetracarnonitriles with 1,3,5-triaryl-2,4-diaza-1,4-pentadienes depending on the solvent used.Chuvash State University, Cheboksary 428015. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1395–1409, October, 1996. Original article submitted October 2, 1996. 相似文献
997.
V. A. Samsonov L. B. Volodarskii I. Yu. Bagryanskaya Yu. V. Gatilov 《Chemistry of Heterocyclic Compounds》1996,32(8):907-913
Compounds containing the pyrroline-N-oxide ring are obtained when isonitrosoketones — 2,6-dihydroxyiminocyclohexanone and -isonitrosoacetophenone — react with enamines. The compounds obtained behave as synthetic equivalents of 1,4-dicarbonyl compounds when undergoing reaction with amines, hydrazine, and hydroxylatnine.Novosibirsk Institute of Organic Chemistry, Siberian Section of the Russian Academy of Sciences (SO RAN) Novosibirsk, 630090. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1055–1061, August, 1996. Original article submitted February 28, 1996. 相似文献
998.
F. M. Bobonich Yu. G. Voloshina V. N. Solomakha 《Theoretical and Experimental Chemistry》1996,32(1):47-50
It was shown that acid-resistant modifications of faujasite can be produced by its thermal treatment in silicon tetrafluoride vapor if the ratio of the atoms in the zeolite framework is increased as a result of such treatment to Si/Al 12. At lower degrees of isomorphous substitution of the atoms. the faujasite crystal lattice is destroyed in a 5 M solution of hydrochloric acid as a result of the low acid resistance of the aluminum-oxygen tetrahedra of the zeolite and of the imperfections in its structure.L. V. Pisarzhevskii Institute of Physical Chemistry, National Academy of Sciences of Ukraine, Kiev. Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 32, No. 1, pp. 51–54, January–February, 1996. Original article submitted March 20, 1995. 相似文献
999.
Gerhard Hasslinger Erik S. Rieger 《The Journal of the Operational Research Society》1996,47(5):640-653
This paper deals with approximate analysis methods for open queueing networks. External and internal flows from and to the nodes are characterized by renewal processes with discrete time distributions of their interarrival times. Stationary distributions of the waiting time, the queue size and the interdeparture times are obtained using efficient discrete time algorithms for single server (GI/G/1) and multi-server (GI/D/c) nodes with deterministic service. The network analysis is extended to semi-Markovian representations of each flow among the nodes, which include parameters of the autocorrelation function. 相似文献
1000.
Steve PhillipsJr. 《The Journal of the Operational Research Society》1996,47(5):697-701
The paper presents an application oriented procedure for solving the project management duration/resource tradeoff problem. A procedure is presented for reducing a project from a normal to a crash duration state at a minimum amount of additional resource expenditure assuming a linear utilization functions. The procedure is network based using a graphical Cut Search Approach to locate the minimal resource level at each reduction in total project duration. Activity-on-arc networks and flow networks are utilized. The paper is presented for practical application and for conceptual development as compared to a theoretical treatment. 相似文献