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931.
双渠道闭环供应链的三种回收模式的建模分析 总被引:2,自引:0,他引:2
针对生产商负责网上直销、零售商负责网下零售、且具有回收再制造功能的双渠道闭环供应链,首先分析了生产商负责产品回收和零售商负责产品回收下生产商和零售商之间的博弈行为,建立了刻画两种回收模式的两层规划模型;进而假定生产商委托第三方企业负责回收,分析了生产商、零售商和第三方回收企业之间的博弈行为,建立了对应此一主两从博弈结构的带均衡约束的两层规划模型.对所得模型进行了模型求解,得到了三种回收模式下双渠道闭环分散式供应链的最优直销价、零售价和回收再制造率决策.通过数值算例对上述三种回收模式进行了比较分析,并对刻画网上直销吸引力的相关参数进行了灵敏度分析.研究发现,生产商负责回收时的回收再制造率最高;网上直销具有激发潜在需求(正效应)和吸引零售市场需求发生转移(负效应)的双重效应等. 相似文献
932.
叠层连续柱壳热应力问题的弱形式研究 总被引:2,自引:0,他引:2
建立了弹性力学基本方程的弱形式,从而得到叠层连续柱壳混合状态方程的边界条件放在一起的算子方程,扩大了求解空间,给出叠层连续闭口柱壳在热荷载和机械荷载作用下的解析解。 相似文献
933.
934.
G-凸度量空间中的广义KKM定理及其应用 总被引:4,自引:1,他引:4
在一类新的G-凸度量空间中建立了一类新的KKM定理,统一、改进和发展了文献中的相应结果.作为应用,得到了几个新的匹配定理和不动点定理. 相似文献
935.
讨论Abel方程闭解的存在性、个数和稳定性,改进了以前文献的结果,并利用关于Abel方程的这些结果得到了一类n次多项式系统在一定条件下极限环的个数和稳定性. 相似文献
936.
亚BCI-代数及其理想 总被引:7,自引:0,他引:7
引入亚BCI-代数的概念,研究了它的基本性质.并在这类代数中引入并讨论了与BCI-代数类似的理想理论. 相似文献
937.
938.
Summary It follows from [1], [4] and [7] that any closed <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"2"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"3"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"4"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"5"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"6"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"7"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"8"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"9"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"10"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"11"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"12"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"13"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"14"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>n$-codimensional
subspace ($n \ge 1$ integer) of a real Banach space $X$ is the kernel of a projection $X \to X$, of norm less than $f(n) +
\varepsilon$~($\varepsilon > 0$ arbitrary), where \[ f (n) = \frac{2 + (n-1) \sqrt{n+2}}{n+1}. \] We have $f(n) < \sqrt{n}$
for $n > 1$, and \[ f(n) = \sqrt{n} - \frac{1}{\sqrt{n}} + O \left(\frac{1}{n}\right). \] (The same statement, with $\sqrt{n}$
rather than $f(n)$, has been proved in [2]. A~small improvement of the statement of [2], for $n = 2$, is given in [3], pp.~61--62,
Remark.) In [1] for this theorem a deeper statement is used, on approximations of finite rank projections on the dual space
$X^*$ by adjoints of finite rank projections on $X$. In this paper we show that the first cited result is an immediate consequence
of the principle of local reflexivity, and of the result from [7]. 相似文献
939.
N. T. Kogabaev 《Siberian Mathematical Journal》2006,47(2):291-297
We study computable Boolean algebras with distinguished ideals (I-algebras for short). We prove that the isomorphism problem for computable I-algebras is Σ 1 1 -complete and show that the computable isomorphism problem and the computable categoricity problem for computable I-algebras are Σ 3 0 -complete. 相似文献
940.
HYPERBOLIC MEAN CURVATURE FLOW:EVOLUTION OF PLANE CURVES 总被引:2,自引:0,他引:2
In this paper we investigate the one-dimensional hyperbolic mean curvatureflow for closed plane curves. More precisely, we consider a family of closed curves F : S1 × [0, T ) → R^2 which satisfies the following evolution equation δ^2F /δt^2 (u, t) = k(u, t)N(u, t)-▽ρ(u, t), ∨(u, t) ∈ S^1 × [0, T ) with the initial data F (u, 0) = F0(u) and δF/δt (u, 0) = f(u)N0, where k is the mean curvature and N is the unit inner normal vector of the plane curve F (u, t), f(u) and N0 are the initial velocity and the unit inner normal vector of the initial convex closed curve F0, respectively, and ▽ρ is given by
▽ρ Δ=(δ^2F /δsδt ,δF/δt) T , in which T stands for the unit tangent vector. The above problem is an initial value problem for a system of partial differential equations for F , it can be completely reduced to an initial value problem for a single partial differential equation for its support function. The latter equation is a hyperbolic Monge-Ampere equation. Based on this, we show that there exists a class of initial velocities such that the solution of the above initial value problem exists only at a finite time interval [0, Tmax) and when t goes to Tmax, either the solution convergesto a point or shocks and other propagating discontinuities are generated. Furthermore, we also consider the hyperbolic mean curvature flow with the dissipative terms and obtain the similar equations about the support functions and the curvature of the curve. In the end, we discuss the close relationship between the hyperbolic mean curvature flow and the equations for the evolving relativistic string in the Minkowski space-time R^1,1. 相似文献
▽ρ Δ=(δ^2F /δsδt ,δF/δt) T , in which T stands for the unit tangent vector. The above problem is an initial value problem for a system of partial differential equations for F , it can be completely reduced to an initial value problem for a single partial differential equation for its support function. The latter equation is a hyperbolic Monge-Ampere equation. Based on this, we show that there exists a class of initial velocities such that the solution of the above initial value problem exists only at a finite time interval [0, Tmax) and when t goes to Tmax, either the solution convergesto a point or shocks and other propagating discontinuities are generated. Furthermore, we also consider the hyperbolic mean curvature flow with the dissipative terms and obtain the similar equations about the support functions and the curvature of the curve. In the end, we discuss the close relationship between the hyperbolic mean curvature flow and the equations for the evolving relativistic string in the Minkowski space-time R^1,1. 相似文献