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11.
给定一个赋权图$G=(V,E;w,c)$以及图$G$的一个支撑子图$G_{1}=(V,E_{1})$,这里源点集合$S=\{s_{1},s_{2},\cdots,s_{k}\}\subseteq V$,权重函数$w:E\rightarrow\mathbb{R}^{+}$,费用函数$c:E\setminus E_{1}\rightarrow\mathbb{Z}^{+}$和一个正整数$B$,本文考虑两类限制性多源点偏心距增广问题,具体叙述如下:(1)限制性多源点最小偏心距增广问题是要寻找一个边子集$E_{2}\subseteq E\setminus E_{1}$,满足约束条件$c(E_{2})$$\leq$$B$,目标是使得子图$G_{1}\cup E_{2}$上源点集$S$中顶点偏心距的最小值达到最小;(2)限制性多源点最大偏心距增广问题是要寻找一个边子集$E_{2}\subseteq E\setminus E_{1}$,满足约束条件$c(E_{2})$$\leq$$B$,目标是使得子图$G_{1}\cup E_{2}$上源点集$S$中顶点偏心距的最大值达到最小。本文设计了两个固定参数可解的常数近似算法来分别对上述两类问题进行求解。  相似文献   
12.
王永久  唐智明 《物理学报》2001,50(12):2284-2288
用参量化后牛顿(PPN)方法计算了质量四极矩对于试验物体轨道进动的影响,得到了在天体物体方面很有意义的优越标架效应和对几个PPN参量的限制. 关键词: 参量化 后牛顿 引力效应  相似文献   
13.
In this paper, we derive two general parameterized boundaries of finite difference scheme for Ve?e???s PDE which is used to price both fixed and floating strike Asian options. Using these two boundaries, we can deal with all kinds of situations, especially, some extreme cases, like overhigh volatility, very small volatility, etc, under which the Asian option is usually mispriced in many existing numerical methods. Numerical results show that our boundaries are pretty efficient.  相似文献   
14.
A new second order time stepping ensemble hybridizable discontinuous Galerkin method for parameterized convection diffusion PDEs with various initial and boundary conditions, body forces, and time depending coefficients is developed. For ensemble solutions in $L^∞$($0$, $T$; $L^2$($Ω$)), a superconvergent rate with respect to the freedom degree of the globally coupled unknowns for all the polynomials of degree $k$ ≥ $0$ is established. The results of numerical experiments are consistent with the theoretical findings.  相似文献   
15.
给定一个赋权图$G=(V,E;w,c)$以及图$G$的一个支撑子图$G_{1}=(V,E_{1})$,这里源点集合$S=\{s_{1},s_{2},\cdots,s_{k}\}\subseteq V$,权重函数$w:E\rightarrow\mathbb{R}^{+}$,费用函数$c:E\setminus E_{1}\rightarrow\mathbb{Z}^{+}$和一个正整数$B$,本文考虑两类限制性多源点偏心距增广问题,具体叙述如下:(1)限制性多源点最小偏心距增广问题是要寻找一个边子集$E_{2}\subseteq E\setminus E_{1}$,满足约束条件$c(E_{2})$$\leq$$B$,目标是使得子图$G_{1}\cup E_{2}$上源点集$S$中顶点偏心距的最小值达到最小;(2)限制性多源点最大偏心距增广问题是要寻找一个边子集$E_{2}\subseteq E\setminus E_{1}$,满足约束条件$c(E_{2})$$\leq$$B$,目标是使得子图$G_{1}\cup E_{2}$上源点集$S$中顶点偏心距的最大值达到最小。本文设计了两个固定参数可解的常数近似算法来分别对上述两类问题进行求解。  相似文献   
16.
We give a general iterative method which computes the maximal real rootx max of a one variable Lipschitzian function in a given interval. The method generates a monotonically decreasing sequence which converges towardsx max or demonstrates the non-existence of a real root in the considered interval. We show that the method is globally convergent and locally linearly convergent. We also compute the number of iterations needed to reach the given accuracy.  相似文献   
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18.
In this paper,we establish the boundedness of parameterized Littlewood-Paley operator μ*,ρλ and parameterized area integral μΩρ,S with kernel satisfying the logarithmic type Lipschitz condition on the weak Hardy space.  相似文献   
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20.
We investigate the constraints on total neutrino mass in the scenario of vacuum energy interacting with cold dark matter. We focus on two typical interaction forms, i.e., Q=βHρc and Q=βHρ. To avoid the occurrence of large-scale instability in interacting dark energy cosmology, we adopt the parameterized post-Friedmann approach to calculate the perturbation evolution of dark energy. We employ observational data, including the Planck cosmic microwave background temperature and polarization data, baryon acoustic oscillation data, a JLA sample of type Ia supernovae observation, direct measurement of the Hubble constant, and redshift space distortion data. We find that, compared with those in the ∧CDM model, much looser constraints on ∑mν are obtained in the Q=βHρc model, whereas slightly tighter constraints are obtained in the Q=βHρ model. Consideration of the possible mass hierarchies of neutrinos reveals that the smallest upper limit of ∑mν appears in the degenerate hierarchy case. By comparing the values of χmin2, we find that the normal hierarchy case is favored over the inverted one. In particular, we find that the difference △χmin2 ≡ χIH; min2NH; min2 > 2 in the Q=βHρc model. In addition, we find that β=0 is consistent with the current observations in the Q=βHρc model, and β < 0 is favored at more than the 1σ level in the Q=βHρ model.  相似文献   
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