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991.
利用博弈论中的相关原理,研究了由一原制造商,一回收制造商和一零售商构成的三级闭环供应链系统.在系统中,原制造商通过向回收制造商收取专利许可费授权其进行再制造,消费者对新产品和再制造品的认可存在差异.研究表明:集中决策下供应链的运作效率明显高于分散决策;无论集中还是分散决策,再制造水平的提高均有利于提高再制品需求量,尽管会抑制部分新产品需求,但仍会使各方利润的增加;在分散决策下再制造节约成本和再制造率的提高均会使原制造商提高单位专利许可费来获取更多利润.最后通过利润分享机制实现了供应链的整体协调,并用一算例对主要结论进行了验证. 相似文献
992.
In this paper, we study an American option‐pricing model with an uncertain volatility. Some properties for the option price are derived. Particularly, a global spread for the option price is proved when the volatility depends on the underlying security and time. This result confirms the observed fact from the real financial data in option markets. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
994.
The thermal and structural properties of binary blends of Nylon-6 (N6) and a chemically related biopolymer, Bombyx mori silk fibroin (SF), are reported in this work. Homopolymers and blends, in composition ratios of N6/SF ranging from 95/05
to 70/30, were investigated by thermogravimetric (TG) analysis, differential scanning calorimetry (DSC), Fourier transform
infrared (FTIR) spectroscopy and wide angle X-ray scattering (WAXS). Silk fibroin typically degrades at temperatures just
above 210°C, which occurs within the melting endotherm of N6. In TG studies, the measured mass remaining was slightly greater
than expected, indicating the blends had improved thermal stability. No beta sheet crystals of SF were detected by FTIR analysis
of the Amide I region.
Strong interaction between N6 and SF chains was observed, possibly as a result of formation of hydrogen bonds between N6 and
SF chains. DSC analysis showed that the addition of SF to N6 caused a decrease in the crystallization temperature, the melting
temperature of the lowest melting crystals and the crystallinity of N6. Furthermore, the α-crystallographic phase dominates
and the γ-crystallographic phase was not observed in N6/SF blends, in contrast to the homopolymer N6, which contains both
phases. We suggest that the addition of SF might result in changes of the chain extension of N6, which lead to the appearance
of α-rather than γ-phase crystals. 相似文献
995.
Zhengnian Chen Hongfeng Xie Hu Yang Zhiliu Wang Rongshi Cheng 《Frontiers of Chemistry in China》2008,3(3):344-347
The analyses of the composition of a binary mixture composed of two kinds of industrial complicated materials have great importance
for formulation in practice. The present paper provides a quantitative size exclusion chromatography (SEC) method based on
the principle of absolute quantification of SEC to solve the problem. The conventional data treatment procedure for the differential
refractive index (DRI) signal of SEC H(V) is improved first by dividing it with the injected sample weight and leads to a novel defined weight normalized distribution
H
w(V) and its integral I
w(V). These two distributions reflect the response constant of the sample in addition to the conventional normalized distribution
F(V). The difference of the average response constants of the composing components provides a sensitive method to compute the
composition of their mixture from its H
w(V) or I
w(V). The method was applied to mixtures of a kind of industrial asphalt and paraffin diluents as an example, and successful
results are obtained.
__________
Translated from Acta Polymerica Sinica, 2007, 8: 689–692 [译自:高分子学报] 相似文献
996.
Esmail Mohammadian Elaheh Rahimpour Fleming Martinez 《Physics and Chemistry of Liquids》2018,56(6):751-758
The solubility of budesonide (BDS) in binary mixtures of ethanol and water at T = (293.2–313.2) K is determined and mathematically represented using two cosolvency models, i.e. Jouyban–Acree model and Jouyban–Acree–van’t Hoff model. The mean relative deviations for fitting the solubility data of BDS in binary mixtures of ethanol + water are 6.6% and 6.5%, respectively. Furthermore, the apparent thermodynamic properties, dissolution enthalpy, dissolution entropy, and Gibbs free energy change of dissolution process of BDS in all the mixed solvents were calculated according to van’t Hoff and Gibbs equations. Dissolution of BDS in these mixed solvents is an endothermic process. 相似文献
997.
Alessandra Frabetti 《Journal of Algebraic Combinatorics》2001,13(1):41-65
Planar binary trees appear as the the main ingredient of a new homology theory related to dialgebras, cf.(J.-L. Loday, C.R. Acad. Sci. Paris
321 (1995), 141–146.) Here I investigate the simplicial properties of the set of these trees, which are independent of the dialgebra context though they are reflected in the dialgebra homology.The set of planar binary trees is endowed with a natural (almost) simplicial structure which gives rise to a chain complex. The main new idea consists in decomposing the set of trees into classes, by exploiting the orientation of their leaves. (This trick has subsequently found an application in quantum electrodynamics, c.f. (C. Brouder, On the Trees of Quantum Fields, Eur. Phys. J. C12, 535–549 (2000).) This decomposition yields a chain bicomplex whose total chain complex is that of binary trees. The main theorem of the paper concerns a further decomposition of this bicomplex. Each vertical complex is the direct sum of subcomplexes which are in bijection with the planar binary trees. This decomposition is used in the computation of dialgebra homology as a derived functor, cf. (A. Frabetti, Dialgebra (co) Homology with Coefficients, Springer L.N.M., to appear). 相似文献
998.
A code
is called (t, 2)-identifying if for all the words x, y(x y) and
the sets (B
t
(x) B
t
(y)) C and
are nonempty and different. Constructions of such codes and a lower bound on the cardinality of these codes are given. The lower bound is shown to be sharp in some cases. We also discuss a more general notion of
-identifying codes and introduce weakly identifying codes. 相似文献
999.
Yuji?YoshidaEmail author Masami?Yasuda Jun-ichi?Nakagami Masami?Kurano 《Fuzzy Optimization and Decision Making》2005,4(3):191-207
To solve a mathematical model for American put option with uncertainty, we utilize two essentials, i.e., a λ-weighting function and a mean value of fuzzy random variables simultaneously. Estimation of randomness and fuzziness as uncertainty should be important when we deal with a reasonable and natural model extended from the original optimization/decision making. Three kinds of mean values by fuzzy measures, which are based on Possibility, Necessity and Credibility, are demonstrated particularly. We consider the optimal expected price of the American put option by dynamic programming under a reasonable assumption. A numerical example is given to illustrate our idea. 相似文献
1000.
A. Kohen F. Giubileo Th. Proslier F. Bobba A. M. Cucolo W. Sacks Y. Noat A. Troianovski D. Roditchev 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(1):21-25
Using Scanning Tunneling Microscope at low temperature
we explore the superconducting phase diagram in the π-band of
the two-band superconductor MgB2. In this band the peculiar
shape of the local tunneling spectra and their dynamics in the
magnetic field reveal the complex character of the quasiparticle
density of states (DOS). The gap in the DOS is first rapidly
filled with states in raising the magnetic field up to 0.5 T and
then slowly approaches the normal state value: the gap is
observed up to 2 T. Such a change in the DOS dynamics suggests the
existence of two terms in the DOS of the π-band: a first one,
reflecting an intrinsic superconductivity in the band and a second
one, originating from an inter-band coupling to the σ-band.
Our findings allow a deeper understanding of the unique phase
diagram of MgB2. 相似文献