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991.
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Takao Kato Changho Keem Akira Ohbuchi 《Abhandlungen aus dem Mathematischen Seminar der Universit?t Hamburg》1999,69(1):319-333
We give necessary and sufficient conditions for non-special line bundles of degree2g — 2 and 2g — 3 being not normally generated. We also provide criteria for special line bundles of degreed > 2g — 6 being normally generated.
This work was done under JSPS-KOSEF joint research program 1997. The first named author was partially supported by Grant-in-Aid
for Scientific Research, the Ministry of Education, #10440051. The second named author was partially supported by BSRI(1998-015-D00023)
and SNU(99-5-l-031). During the period when this paper was prepared for publication, the second named author was enjoying
the hospitality of ICTP. The third named author was partially supported by Grant-in-Aid for Scientific Research, the Ministry
of Education, #09640043. 相似文献
994.
The number of hospitals in Japan exceeds 10,000, and every month nurses are scheduled to shifts in about 30,000 units in total. There is serious demand for automating this scheduling task. In this paper, we introduce a mathematical programming formulation of the nurse scheduling problem in Japan, and develop a meta-heuristic approach to solve the problem. This scheduling problem is a hard combinatorial problem due to tight constraints involving such factors as the skill level of a team, the need to balance workload among nurses, and the consideration of nurses' preferences, even though the number of the nurses to be scheduled is not large, at between 20 and 40. The performance of our approach is demonstrated by the successful solution of data taken from actual scheduling problems. The proposed model and approach can be adapted for the majority of hospitals in Japan, as well as for some hospitals in other countries, and is likely applicable to many other scheduling problems in the fields of business and logistics.
Key words.nurse scheduling – block-angular problem – subproblem – integer programming – relaxation – tabu search – branch-and-boundMathematics Subject Classification (1991):20E28, 20G40, 20C20 相似文献
995.
The principal 3-block of a Chevalley group G2(q) with q a powerof 2 satisfying q 2 or 5 mod 9 and the principal 3-block ofG2(2) are Morita equivalent. 2000 Mathematical Subject Classification:20C05, 20C20, 20C33. 相似文献
996.
In this paper we consider the number t of columns (1,k–2,1) in the intersection array of a distance-regular graph. We prove that t is at most one if k58. 相似文献
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999.
Takahashi K Kawakami T Gu ZZ Einaga Y Fujishima A Sato O 《Chemical communications (Cambridge, England)》2003,(18):2374-2375
The first preparation of an Fe(II) spin-crossover complex including a 1,3-dithiole ligand is reported. Crystal analyses of both the low- and the high-temperature phases reveal that short S...S contacts play a key role in an abrupt spin transition. 相似文献
1000.
Yamayoshi A Iwase R Yamaoka T Murakami A 《Chemical communications (Cambridge, England)》2003,(12):1370-1371
Hairpin type psoralen-cojugated oligonucleotides cross-linked with RNA when they hybridized with a perfectly complementary RNA. 相似文献