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71.
Bernard Gendron Jean-Yves Potvin Patrick Soriano 《Annals of Operations Research》2003,122(1-4):193-217
In this paper, a tabu search heuristic is combined with slope scaling to solve a discrete depot location problem, known as the multicommodity location problem with balancing requirements. Although the uncapacitated version of this problem has already been addressed in the literature, this is not the case for the more challenging capacitated version, where each depot has a fixed and finite capacity. The slope scaling approach is used during the initialization phase to provide the tabu search with good starting solutions. Numerical results are reported on various types of large-scale randomly generated instances. The quality of the heuristic is assessed by comparing the solutions obtained with those of a commercial mixed-integer programming code. 相似文献
72.
73.
Jean-Yves Hée 《Journal of Algebra》2008,319(11):4738-4758
We consider groups endowed with root data associated with non-necessarily finite root systems. We generalise to these groups the twisting methods of Chevalley groups initiated by Steinberg and Ree. The resulting theorem (proved in 1988) can be applied to Kac–Moody groups: see for instance two papers published by J. Ramagge in 1995 [J. Ramagge, On certain fixed point subgroups of affine Kac–Moody groups, J. Algebra 171 (2) (1995) 473–514; J. Ramagge, A realization of certain affine Kac–Moody groups of types II and III, J. Algebra 171 (3) (1995) 713–806]. 相似文献
74.
Bachir Zouchoune Jean-François Halet Jean-Yves Saillard 《Journal of Cluster Science》2004,15(3):267-276
The electronic structure of the Cu2(4n+2)Se4n+2(PH3)8 (n = 1–4) D
4h series of model clusters has been analyzed by means of density functional theory calculations. The fused square antiprismatic structure of the metal framework is found to be always preferred over the fused cuboctahedral one because it reinforces the Cu-P bonds. Thus, the presence of the terminal phosphine ligands tends to strengthen the Cu...Cu (d10...d10) bonding by mixing bonding combinations of the vacant Cu 4s and 4p orbitals into the occupied 3d combinations. The calculations indicate that the compounds corresponding to n = 3 and 4 should be easily two-electron-reduced, leading to stable dianionic species. 相似文献
75.
Jean-Yves Mrour FranOise Cossais Simone Piroëlle Daniel Mazas 《Journal of heterocyclic chemistry》1994,31(1):87-92
The Schmidt rearrangement of 1,2,3,5,10,10a-hexahydropyrrolo[1,2-b]isoquinoline-3,10-diones has been studied. The structure of the lactams obtained has been determined by chemical reactivity and characterized by means of ir, 1H and 13C nmr spectroscopy. 相似文献
76.
Dominique Toledo Octavio Peña Thierry Roisnel Jean-Yves Pivan 《Journal of Coordination Chemistry》2018,71(1):22-34
One coordination polymer, [Co(3-ctpy)2(H2O)2]n*2nEtOH (1), was synthesized by a solvothermal method mixing the complex precursor cobalt(II) acetylacetonate (Co(acac)2*2H2O) with 4′-(4-carboxyphenyl)-3,2′:6′,3″-terpyridine (3-Hctpy). This paramagnetic complex has been isolated as a neutral, air and thermal stable solid and has been characterized by elemental analysis, FT-IR and single-crystal X-ray diffraction analysis. The thermal stability and photoluminescence properties were studied in the solid state. The magnetic behavior presents an interesting challenge since the Co(II) ion has a spin 3/2, which leads to multiple possibilities under the influence of an energy crystal field, from the identification of the ground state to possible transitions to excited states. The usual orbital contribution of the magnetic moment has been extinguished, due to an axially distorted octahedral environment for cobalt, changing the Oh symmetry (with 4T1g ground state) to D4h (with 4A2g ground state). This decrease in symmetry is responsible for the quenching of the orbital contribution, as will be discussed in this article. 相似文献
77.
Alain Lascoux Bernard Leclerc Jean-Yves Thibon 《Communications in Mathematical Physics》1996,181(1):205-263
We present a fast algorithm for computing the global crystal basis of the basic
-module. This algorithm is based on combinatorial techniques which have been developed for dealing with modular representations of symmetric groups, and more generally with representations of Hecke algebras of typeA at roots of unity. We conjecture that, upon specializationq1, our algorithm computes the decomposition matrices of all Hecke algebras at an
th root of 1.Partially supported by PRC Math-Info and EEC grant n0 ERBCHRXCT930400. 相似文献
78.
Stephen F. Smith Peng Si Ow Jean-Yves Potvin Nicola Muscettola Dirk C. Matthys 《The Journal of the Operational Research Society》1990,41(6):539-552
Practical solutions to the production scheduling problem must provide two broad capabilities:
We describe the architecture of OPIS (opportunistic intelligent scheduler), which defines a general framework for configuring scheduling systems according to this view. We then examine the scheduling knowledge (e.g. analysis and scheduling methods, schedule generation or revision strategies) that is exploited within this architecture by the current OPIS scheduler. Experimental studies with the OPIS scheduler have demonstrated the potential of this constraint-directed scheduling methodology in both predictive and reactive scheduling contexts. 相似文献
- i)an ability to efficiently generate schedules that reflect the actual constraints and objectives of the manufacturing environment, and
- ii)an ability to incrementally revise these schedules over time in response to unexpected executional circumstances. In this paper, we advocate a common view of predictive and reactive scheduling as an incremental problem solving process that is opportunistically focused by characteristics of the current solution constraints.
79.
80.
功能化聚(2,5-二甲氧基苯胺)膜的电化学和电催化性质研究 总被引:1,自引:0,他引:1
聚(2,5-二甲氧基苯胺)含有对称的环取代基,其电化学活性可与PAni相比拟.该聚合物具有三种氧化态,即完全还原态(L)、半氧化态(E)和完全氧化态(P),在伏安曲线上分别于0.19和0.51V处出现L/E和E/P转变峰.掺杂态聚合物和本征态聚合物的氧化还原分别经历L=EH=P和LH=EH=P路径,其中E/P转变峰电位随pH升高而发生负移.铂化的聚合物电极对异丙醇的氧化具有明显的催化作用,且随着扫描时间延长,氧化电流逐渐提高;聚合物与铂微粒相互作用,改变铂微粒的几何结构和电子性质,使催化体系具有良好的催化活性和抗中毒能力.在pH=4.7的缓冲溶液中,该修饰电极对异丙醇氧化仍具有催化活性.聚合物在空气中存放太久(3年)会发生降解,从而影响其电化学性质. 相似文献