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131.
黄庆学 《浙江大学学报(理学版)》2005,32(4):361-363
作为完全图的最优完全二部图分解的推广,引进了完全k一致超图的最优k团分划的新概念;并对k=3推广了Graham-Pollak定理,给出了这种情形的特性;同时,对一般情形给出了最优k团分划的一个上界. 相似文献
132.
Thomas Zaslavsky 《Discrete and Computational Geometry》2002,27(3):303-351
For each pair (Q
i
,Q
j
) of reference points and each real number r there is a unique hyperplane h \perp Q
i
Q
j
such that d(P,Q
i
)
2
- d(P,Q
j
)
2
= r for points P in h . Take n reference points in d -space and for each pair (Q
i
,Q
j
) a finite set of real numbers. The corresponding perpendiculars form an arrangement of hyperplanes. We explore the structure
of the semilattice of intersections of the hyperplanes for generic reference points. The main theorem is that there is a real,
additive gain graph (this is a graph with an additive real number associated invertibly to each edge) whose set of balanced
flats has the same structure as the intersection semilattice. We examine the requirements for genericity, which are related
to behavior at infinity but remain mysterious; also, variations in the construction rules for perpendiculars. We investigate
several particular arrangements with a view to finding the exact numbers of faces of each dimension. The prototype, the arrangement
of all perpendicular bisectors, was studied by Good and Tideman, motivated by a geometric voting theory. Most of our particular
examples are suggested by extensions of that theory in which voters exercise finer discrimination. Throughout, we propose
many research problems.
Received July 20, 2000, and in revised form September 29, 2001, and October 12, 2001. Online publication March 4, 2002. 相似文献
133.
《Discrete Mathematics》2023,346(5):113309
In this work, we study Schmidt's partition theorem in a combinatorial manner, and find a strong refinement which connects the minimal excludant of ordinary partitions to the length of Schmidt's partitions. As a byproduct, we obtain a bivariate form of an identity recorded in Ramanujan's lost notebook. 相似文献
134.
我国北方地区的土石坝和水池的防渗沥青混凝土面板,常出现低温裂缝。因此,对沥青混凝土在低温条件下的温度应力疲劳进行实验研究很有必要.本项研究研制了适用于沥青混凝土低温低周大变形的弯曲疲劳试验机,进行了沥青混凝土在不同低温下的疲劳破坏性能试验。对试验结果用粘弹性理论和推广的应变区分法(SRP)和应变能区分法(SEP)进行了分析,首次得出了沥青混凝土的疲劳寿命与弯曲应力、应变和应变能的关系,并试用于实际工程的予测. 相似文献
135.
LI Xi-kui 《应用数学和力学(英文版)》2005,26(8):1056-1063
IntroductionIt is known that standard finite element procedure is unable to simulate the wavepropagation with high oscillations or gradients in space in the media with reasonableefficiency and accuracy due to the nature of polynomial interpolation approxi… 相似文献
136.
Bisson J Poupard P Pawlus AD Pons A Darriet P Mérillon JM Waffo-Téguo P 《Journal of chromatography. A》2011,1218(36):6079-6084
The phytochemical study of the root extract of the stilbenoid-rich Vitis riparia × Vitis berlandieri grapevine was carried out by centrifugal partition chromatography (CPC). For this reason, we developed a new elution mode we named back-step, which allowed us to obtain cleaner fractions and a more efficient separation process when used in conjunction with a classical elution approach. Three hydroxystilbenes: (E)-resveratrol, (E)-?-viniferin and (E)-vitisin C, with greater than 90% purity were thus obtained through such process, with minimal sample handling and purification steps. Online coupling of CPC to ESI mass spectrometry was used for optimization of the separation parameters and to facilitate the characterization of the stilbenoids. This study details the first phytochemical investigation of stilbenoids from the hybrid species together with a new elution mode able to widen the range of ARIZONA biphasic systems. 相似文献
137.
István Faragó Róbert Horváth Sergey Korotov 《Numerical Methods for Partial Differential Equations》2011,27(3):702-720
In this article, we derive and discuss sufficient conditions for providing validity of the discrete maximum principle for nonstationary diffusion‐reaction problems with mixed boundary conditions, solved by means of simplicial finite elements and the θ time discretization method. The theoretical analysis is supported by numerical experiments. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2011 相似文献
138.
Mohamad Toutounji 《International journal of quantum chemistry》2011,111(9):1885-1892
Exact closed forms of the equilibrium partition functions in terms Jacobi elliptic functions are derived for a particle in a box and Rosen–Morse (Poschl–Teller) oscillator (perfect for modeling bending vibrational modes). An exact form of the equilibrium partition function of Morse oscillator is reported. Three other approximate forms of Morse partition function are presented. Having an exact closed‐form for the vibrational partition function can be very helpful in evaluating thermodynamic state functions, e.g., entropy, internal energy, enthalpy, and heat capacity. Moreover, the herein presented closed forms of the vibrational partition function can be used for obtaining spectroscopic and dynamical information through evaluating the two‐ and four‐point dipole moment time correlation functions in anharmonic media. Finally, a closed exact form of the rotational partition function of a particle on a ring in terms of the first kind of complete elliptic integral is derived. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献
139.
Peter J. Cameron 《Discrete Mathematics》2011,311(13):1074
Open problems from the problem session at the 22nd British Combinatorial Conference at St Andrews, on 10 July 2009. 相似文献
140.
Let ab=n2. We define an equitable Latin rectangle as an a×b matrix on a set of n symbols where each symbol appears either or times in each row of the matrix and either or times in each column of the matrix. Two equitable Latin rectangles are orthogonal in the usual way. Denote a set of ka×b mutually orthogonal equitable Latin rectangles as a k– MOELR (a,b;n). When a≠9,18,36, or 100, then we show that the maximum number of k– MOELR (a,b;n)≥3 for all possible values of (a,b). 相似文献