标准体系的使用期的模型与分析

本文提出了关于标准体系使用期的两个模型。首先定义了标准使用期,然后讨论了模型的合理性。通过模型讨论了标准使用期的性质,给出了数值示例。提出了需进一步研究的问题。     

利用介孔材料制备碳纳米管的形貌、结构和Raman散射研究

以碳氢气体为反应物,利用化学气相沉积方法,在不同的衬底上制备了碳纳米管。研究了不同衬底对碳纳米管生长方式的影响。对碳纳米管的形貌和结构进行了观察研究,在介孔二氧化硅衬底上制备了取向生长的碳纳米管。碳纳米管具有很高的密度和纯度。研究了取向碳纳米管的Raman谱,分析了碳纳米管的Raman共振特性与其微观结构的关系。     

基于基元方法的创造性模仿创新研究

论文立足于二次创新中的创造性模仿创新,分析了我国采用这种技术创新的必要性和可行性。以石油机械行业中的振动筛产品为例,运用可拓创新方法研究描述了整个创新过程,并借助可拓变换方法获得了新的创新产品。该方法的运用得到了满意的创新产品,提高了新兴技术的利用率,实证了可拓方法的科学性和有效性。     

一个基于模糊偏好的选择函数

研究了一个基于模糊偏好关系的模糊选择函数。首先对文献中基于普通关系的最好元集所确定的选择函数进行了回顾,并给出了进一步结果。然后,讨论了该选择函数的模糊化形式,给出了基于模糊偏好的选择集确定模糊选择函数的充要条件,同时研究了该选择函数的合理性性质。     

陷阱有多深?

正青青草原的春天来了,灰太狼一家外出踏青。小灰灰忙着抓蝴蝶,正玩得起劲,突然听到爸爸妈妈的求救声。呀!爸爸妈妈掉进陷阱里了。一家人想了很多办法,又是跳又是爬,但是陷阱太深了,灰太狼和红太狼怎么都出不来。小灰灰急得快要哭出来了。突然,他想起了羊村里的朋友们,就急忙去羊村求救。羊村的羊羊们来救援了。为了教育一下灰太狼,喜羊羊想出了一个主意,说:"灰太狼先生,我这儿有一根绳子,把绳子放到一口井里,单根放到井底,井外会多出15米。对折后再放入,会多出井口1米。你知道这口井有多深,绳子有多长吗?"     

缺失数据下半参数单调回归模型的估计

研究了响应变量缺失情况下半参数单调回归模型的估计问题。利用嵌入核估计的方法得到了参数部分的估计,在此基础上构造了非参数部分的单调约束最小二乘估计。证明了参数估计的渐近分布为正态分布,得到了非参数部分估计的收敛速度。通过随机模拟研究了有限样本量下估计的表现。     

娄洁等： 一类有被动免疫的流行病模型研究

对一类具有被动免疫的流行病模型进行了定性分析和讨论。得到了这些模型的基本再生数R_0，对有些模型得到了地方病平衡点的全局稳定性。并且在MSIR模型中还考虑了接种。     

考驾照之外星奇遇记

正在未来的飞船驾驶学校,由于高度的电脑化操作,每个年满9岁的孩子就可以去考太空驾驶执照了。考试很简单,只需要坐在飞船上按一个按钮就可以了。但就算这样,贝卡也遇到了麻烦。贝卡有恐高症,可是明天就要考试了,他一直在想:我该怎么办呢,7他想着想着就睡着了,并且做了一个梦。     

考虑零售商竞争的供应链契约选择模型

传统的面向竞争性供应链协调的契约设计的高复杂度使得契约学习的成本大大提高,难以在现实中得到普遍应用。研究了由一个供应商和两个竞争性零售商构成的供应链的协调问题。分析了竞争性零售商对简单契约的选择问题,设计了一种不同于以往单一契约模式的契约选择模型,为订货能力不同的零售商提供可供选择的数量折扣契约和批发价格契约。实现了供应链的最优协调,使分散式决策的供应链的利润达到了集中决策的水平。最后通过具体算例验证了结论。     

连续型指数差分布

本文提出了一个连续型随机变量的概率分布:指数差分布。讨论了该分布的极值、拐点、数学期望和方差,推导了参数的矩估计公式,探讨了该分布与指数分布的关系,给出了该分布在药代动力学中的应用。     

Adjoint and self-adjoint boundary value problems on a geometric graph

We consider boundary value problems of arbitrary order for linear differential equations on a geometric graph. Solutions of boundary value problems are coordinated at the interior vertices of the graph and satisfy given conditions at the boundary vertices. For considered boundary value problems, we construct adjoint boundary value problems and obtain a self-adjointness criterion. We describe the structure of the solution set of homogeneous self-adjoint boundary value problems with alternating coefficients of a differential equation and obtain nondegeneracy conditions for these boundary value problems.     

具有非局部边界条件的奇摄动反应扩散问题

本文研究了一类具有非局部边界条件的奇摄动反应扩散初始边值问题．在适当的条件下，利用比较定理讨论了问题解的渐近性态．     

一类Dirichlet边值逆问题

给出解析函数的一类Dirichlet边值逆问题的数学提法.依据解析函数Dirichlet边值问题和广义Dirichlet边值问题的理论,讨论了此边值逆问题的可解性.利用解析函数Dirichlet边值问题的Schwarz公式,给出了该边值逆问题的可解条件和解的表示式.     

A method of convolution of Fourier expansions as applied to solving boundary value problems with intersecting interface lines

An efficient method of construction of solutions to a set of boundary value problems with additional interface conditions, more complicated boundary conditions, and so on on the basis of known solutions to classical boundary value problems is proposed. The method is based on the representation of solutions to classical and more complicated problems in the form of expansions into Fourier series with subsequent reduction of one series to the other. As a result, formulas directly expressing solutions to more complicated problems in terms of solutions to classical problems are obtained. On the basis of the well-known solution to the Dirichlet problem on a half plane, solutions to boundary value problems with interface conditions (including generalized conditions of the type of a crack and a screen) on intersecting straight lines for boundary conditions of the first and the third kind are obtained.     

Mixed boundary value problems and parametrices in the edge calculus

Mixed elliptic boundary value problems are characterised by conditions which have a jump along an interface of codimension 1 on the boundary. We study such problems in weighted edge spaces and show the Fredholm property and the existence of parametrices under additional conditions of trace and potential type on the interface. We develop a new method for computing the interface conditions in terms of the index of boundary value problems in weighted spaces on infinite cones, combined with structures from the calculus of boundary value problems on a manifold with edges. This will be illustrated by the Zaremba problem and other mixed problems for the Laplace operator. The approach itself is completely general.     

Noncoercive Boundary Value Problems for Elliptic Partial Differential and Differential-Operator Equations

In this paper we find conditions guarantee that irregular boundary value problems for elliptic differential-operator equations of the second order in an interval are fredholm. We apply this result to find some algebraic conditions guarantee that irregular boundary value problems for elliptic partial differential equations of the second order in cylindrical domains are fredholm. Apparently this is the first paper where the regularity of an elliptic boundary value problem is not satisfied on a manifold of the dimension equal to dimension of the boundary. Nevertheless the problem is fredholm and the resolvent is compact. It is interesting to note that the considered boundary value problems for elliptic equations in a cylinder being with separating variables are noncoercive.     

Degenerate elliptic boundary value problems

In this paper we find conditions that guarantee that regular boundary value problems for elliptic differential-operator equations of the second order in an interval are coercive and Fredholm, and we prove the compactness of a resolvent. We apply this result to find some algebraic conditions that guarantee that regular boundary value problems for degenerate elliptic differential equations of the second order in cylindrical domains have the same properties. Note that considered boundary value conditions are nonlocal and are differential only in their principal part, and a domain is nonsmooth.     

椭圆型方程的内层和边界层渐近解

本文讨论了一类半线性椭圆型方程边值问题.利用微分不等式理论,研究了边值问题内层和边界层解的存在性和渐近性态.     

A CLASS OF NONLOCAL BOUNDARY VALUE PROBLEMS OF NONLINEAR ELLIPTIC SYSTEMS IN UNBOUNDED DOMAINS

We consider the following boundary value problem ill the unbounded donain Liui = fi(x,u, Tu), i = 1, 2,' ! N,x E fl, (1) olLi "i0n Pi(x)t'i = gi(x,u), i = l, 2,',N,x E 0fl, (2) where x = (x i,', x.), u = (u1,' f uN), Th = (T1tti,', TNi'N) and [ n. 1 L, = -- I Z ajk(X)the i0j(X)C], Li,k=1' j=1 J] l Ltti = / K(x,y)ui(y)dy, x E n. jn K(x, y)ui(y)dy, x E n. Q denotes an unbounded dolllain in R", including the exterior of a boullded doinain and 0…     

一类具有非局部边界条件的半线性椭圆型方程奇摄动问题

本文研究了一类具有非局部边界条件的奇摄动半线性椭圆型方程边值问题。在适当的条件下，利用比较定理讨论了问题解的渐近性态。