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991.
June?DongEmail author Ding?Zhang Hong?Yan Anna?Nagurney 《Annals of Operations Research》2005,135(1):155-178
In this paper, we present a supply chain network model with multiple tiers of decision-makers, consisting, respectively, of
manufacturers, distributors, and retailers, who can compete within a tier but may cooperate between tiers. We consider multicriteria
decision-making for both the manufacturers and the distributors whereas the retailers are subject to decision-making under
uncertainty since the demands associated with the product are random. We derive the optimality conditions for the decision-makers,
establish the equilibrium conditions, and derive the variational inequality formulation. We then utilize the variational inequality
formulation to provide both qualitative properties of the equilibrium product shipment, service level, and price pattern and
to propose a computational procedure, along with convergence results. This is the first supply chain network model to capture
both multicriteria decision-making and decision-making under uncertainty in an integrated equilibrium framework. 相似文献
992.
Anna?Dall’AcquaEmail author Guido?SweersEmail author 《Annali di Matematica Pura ed Applicata》2005,184(3):361-374
Hadamard claimed in 1907 that the clamped-plate equation is positivity preserving for domains which are bounded by a Limaçon de Pascal. We will show that this claim is false in its full generality. However, we will also prove that there are nonconvex limaçons for which the clamped-plate equation has the sign-preserving property. In fact we will give an explicit bound for the parameter of the limaçon where sign change may occur. Mathematics Subject Classification (2000) 35J40, 35Q72, 35B50 相似文献
993.
Paul Houston Ilaria Perugia Anna Schneebeli Dominik Schötzau 《Numerische Mathematik》2005,100(3):485-518
Summary In this paper, we introduce and analyze the interior penalty discontinuous Galerkin method for the numerical discretization of the indefinite time-harmonic Maxwell equations in the high-frequency regime. Based on suitable duality arguments, we derive a-priori error bounds in the energy norm and the L2-norm. In particular, the error in the energy norm is shown to converge with the optimal order (hmin{s,}) with respect to the mesh size h, the polynomial degree , and the regularity exponent s of the analytical solution. Under additional regularity assumptions, the L2-error is shown to converge with the optimal order (h+1). The theoretical results are confirmed in a series of numerical experiments.Supported by the EPSRC (Grant GR/R76615).Supported by the Swiss National Science Foundation under project 21-068126.02.Supported in part by the Natural Sciences and Engineering Council of Canada. 相似文献
994.
1J(13C13C) has been determined in naturally abundant samples of η1,η2 -alkenyl-η5 -cyclopentadienylnickel complexes; for the coordinated double bonds 1J(CC) lies between the value for free ethylene and cyclopropane, and therefore gives direct insight into the relevant bonding situation. 相似文献
995.
Ewa Skrzypczak-Jankun Hanna Małuszyńska Anna Perkowska Zygmunt Kałuski 《Journal of chemical crystallography》1980,10(3-4):67-74
The formula of the title compound is C16H27ClN2O5,MW = 362.9 orthorhombic,P212121,a = 8.403(1),b= 13.133(1),c= 15.972(2) Å,Z = 4,D
x
= 1.37 g cm–3, (CuK) = 2.2 mm-1. The lupanine skeleton has atrans-trans configuration. The ringA has a half-chair conformation, theB andD rings adopt a chair form, and theC ring forms a boat. The lupanine cations are linked together by the intermolecular hydrogen bonds forming infinite chains alongb. The N(16) ... O(C2) distance is 2.763(7) Å. 相似文献
996.
Absorption and luminescence spectra, depopulation kinetics of the lowest excited singlet and triplet states and acid-base equilibria were investigated for neutral and protonated diazaphenanthrenes: 2,3-, 1,4- and 5,6-DAF. The spectroscopical results are correlated with CNDO/S calculations. Profound influence of topology upon photophysical and chemical (basicity) properties has been stated and discussed. 相似文献
997.
Marina Biagini Cingi Anna Maria Manotti Lanfredi Antonio Tiripicchio Marisa Tiripicchio Camellini 《Transition Metal Chemistry》1979,4(4):221-224
Summary The crystal structure of CuCl2(C7H8N4O2)(H2O)2 has been determined from diffractometer data by Patterson and Fourier methods and refined by full-matrix least-squares to R=0.067 for 2123 observed reflections. Unit cell constants are:a=9.930(8),b=9.987(8),c=7.483(6) Å,=123.2(1),=94.5(1),= 83.9(1)°. The space group is P¯1 withZ=2. The structure consists of diaquadichlorotheophyllinecopper(II) complexes linked by hydrogen bonds. The coordination polyhedron of copper is a square pyramid whose base, severely tetrahedrally distorted, is formed by a water molecule [Cu-Ow=2.025(7) Å], two chlorines [Cu-Cl=2.273(4), 2.296(4) Å] and an imidazole nitrogen [Cu-N=1.983(9) Å] from the theophylline ligand. A second water molecule is at the apex of the pyramid [Cu-Ow=2.292(7) Å]. Coordination is completed to a distorted octahedral one by a long Cu ... O=3.164(7) Å contact involving the exocyclic oxygen at C6 of the theophylline ligand. 相似文献
998.
Lidia Prajer-Janczewska Anna Postawka Krystyna Koćma Krystyna Rudolf 《Monatshefte für Chemie / Chemical Monthly》1968,99(3):1175-1176
Ohne ZusammenfassungMit 1 Abbildung 相似文献
999.
Alessandra Borrelli Marziano Marziani Anna Maria Rangoni 《Annali dell'Universita di Ferrara》1976,22(1):171-184
Riassunto Si studia l'influenza della polarizzazione delle radio-onde su alcuni fenomeni non lineari nella ionosfera tramite una nuova
e più completa relazione funzionale fra i vettori densità di corrente e campo elettrico. Tale studio riguarda la comparsa
di onde di banda laterale e la loro dipendenza dalle direzioni di polarizzazione delle onde interagenti.
Summary The influence of radio wave polarization on some nonlinear phenomena in the inosphere is studied through a new and more complete functional relation between current density and electric field vectors. This study is concerned with the occurrence of ?sideband? waves and their dependence on the polarization directions of interacting waves.相似文献
1000.
A method for quantitative characterization of the noncrystalline region in poly(ethylene terephthalate) (PET) fibers based on x-ray wide-angle diffraction data is elaborated. The procedure consists in a computational resolution of the diffracted intensity into individual peaks for 010, 11 0, and 100 planes and into isotropic and anisotropic components of diffuse scattering. The results show that the content of mesomorphic regions in the noncrystalline part of PET fibers with draw ratio of λ = 3.0 varies from 12% to 32% depending on the temperature of heat treatment. 相似文献