不可解

There are series of papers studying the solvability of an incompressible, viscous, instationary fluid contained in a domian bounded entirely by a free surface. In 1977, Solonnikov proved its local solvability in a Holder space for any initial date but without surface tension. In 1984, he considered the same problem in a Sobolev space with surface tension being taken into account. In I992, Mogilevskii and Solonnikov treated the same problem in a Holder space, where the coefficient of surface tension is not a constant. There are also short-time existence results for the solvability of an incompressible, vicous, unsteady fluid bounded above by a free surface and below by a fixed bottom which approach horizontal planes at infinity. In 1981, Beale proved its local solvability in a Sobolev space for any initial date but without surface tension. In 1983, Allain were concerned with the same problem in R〓 with surface tension but under the assumption that the initial fluid domain was near a horizontal strip. In 1987, he obtained the same result without the preceding assumption. In 1996, Tani solved the same problem in R with surface tension. For the solvability of an incompressible viscous instationary fluid in Ω R bounded inside by a free surface S and outside by a rotating boundary S, in 1995 Ciuperca proved its local existence in a Sobolev space for any initial date but without surface tension. In this paper, we consider the same problem with surface tension.

对于边界完全是由自由边界组成的有界区域中粘性不可压流体的非定常运动问题，Solonnikcv于1977年在忽略表面张力情况下证明了初值问题小时间解在Holder空间的存在性，于1984年在有表面张力情况下证明了初值问题问题小时间解在Sobolev空间的存在性，Mogilevskii和Solonnikov于1992年在表面张力系数可以不是常数情况下证明了初值问题小时间解在Holder空间的存在性；对于上面是自由边界、下面是固定边界且两边界在无限处趋于水平的无限区域中粘性不可压流体的非定常运动问题，Beale于1981年在忽略表面张力情况下证明了初值问题小时间解在Sobolev空间的存在性，Allain于1983年在有表面张力情况下证明了R中初值问题小时间解在Sobolev空间的存在性，但其中假定初始区域近似是个水平条，他于1987年去掉了这个假定得到同样的结果，Tani于1996年在有表面张力情况下证明了R中初值问题小时间解在Sobolev空间的存在性；对于R中内面是自由边界、外面是旋转边界S的有界区域中粘性不可压流体的非定常运动问题，Ciuperca于1995年在忽略表面张力情况下证明了初值问题小时间解在Sobolev空间的存在性，本文考虑了在有表面张力情况下初值问题可解性问题。

Our analysis framework relies on the reflected Backward Stochastic Differential equation approach.We characterize the value functions of the noncallable bonds in terms of the reflected Backward Stochastic Differential equation,Then the relationship between the value function of convertible bonds and reflected backward stochastic differential equations with single reflect is built at the same time,and provide the optimal conversion strategy for bondholders.2:We get the value of non-callable convertible bonds by numerical methods.

探讨了可转换债券的最优停时价值与带反射边界倒向随机微分方程解的关系，在市场完备，公司价值只包括股权和可转债这两种权益等各种假定下，给出不可赎回可转换债券的价值函数，证明了不可赎回可转换债券的最优停时问题的解是存在的，同时给出了其最优的转换策略。2：通过数值方法求解不可赎回可转换债券的价值。

In order to determine the solution set of the equation , by the means of meet-irreducible element and irredundant finite meet-decomposition, we first obtain the maximal solutions to the simple equation in the case that b has an irredundant finite meet-decomposition, and then consider the relation between the equation and the equation , based on this, we obtain the maximal solutions to the equation in the case that each element of the matrix B has an irredundant finite meet-decomposition and so determine its solution set completely.

为了确定方程的解集，本文利用交既约元与不可缩短的有限交分解等工具，同样地先求出简单形式的型矩阵方程的所有极大解，然后讨论方程与方程之间的关系，在此基础上，在B的每个元素均有不可缩短的有限交分解的情况下，求出了方程的所有极大解，从而完全确定了方程的解集。

And the sufficient and necessary conditions are obtained and the uniqueness of T is discussed and an algorithm for solving the inverse problem is provided. The other kind of structure inverse eigenvalue problem is for unitary Hessenberg matrices with positive subdiagonal elements. That is, a unitary Hessenberg matrices with positive sub-diagonal elements can be constructed when its eigenvalues and the eigenvalues of H_(11) and H_(22) are known. Here H_(11) and H_(22) are rank-one modifications of k × k leading principal submatrix of H and of its × remain submatrix respectively. In the end, the uniqueness of H and an algorithm is obtained.

文中首先讨论了这三组特征值之间的交错关系，接着确定了该逆问题有解的充要条件，并论证了其解的唯一性问题，最后给出了相应的数值算法；本文第二个问题解决的是一类不可约的酉Hessenberg阵的逆特征值问题：即一个不可约的酉Hessenberg阵可以由它的特征值、它的前k阶秩一修正的顺序主子阵的特征值以及它的后n—k阶余子阵的秩一修正阵的特征值来确定，文中最后讨论了唯一性和相应的算法。

Through such a study, it is also shown that when the time delay is long enough such that the stability switches of the equilibrium of system halt, the bifurcation branches originated from the critical time delays cannot be surely stable or unstable in the whole solution space, that is, their stability depends on cases.

利用打靶法的数值结果说明了当系统平衡点不再发生稳定性切换时，源自这些临界时滞处的解支的稳定性在整个解空间的稳定性具有不可判定性，这也说明由多尺度法所得高阶近似判定的解支的稳定性事实上只表示解支在局部中心流形上的稳定性，而非在整个解空间中的稳定性。

Since our proposed estimating equation is a nondifferentiable function with respect to regression parameters, we also compare two root-finding algorithms for nondifferentiable function, bisection and Nelder-Mead methods, in this thesis.

此外，本文所提出的参数估计式为不可微函数，因此文中也会探讨解不可微函数的两段法和Nelder-Mead所提的方法等两种解根演算法。

A well-tied knot makes use of no rope, and yet cannot be united.

善结无绳约而不可解。

In my view, one cannot help but agree that the subtitle of the Krueger article captures the essence of the problem: Imponderables Meet Uncertainties.

在我看来，我们只能同意Krueger 文章的副标题，它抓住了问题的本质，那就是：&'不可解兄'啊，遇上了'不确定'弟&！

In my view, one cannot helpbut agree that the subtitle of the Krueger article captures the essenceof the problem: Imponderables MeetUncertainties.

在我看来，我们只能同意Krueger文章的副标题，它抓住了问题的本质，那就是：&'不可解兄'啊，遇上了'不确定'弟&！

In my view, one cannot help butagree that the subtitle of the Krueger article captures the essence ofthe problem: Imponderables MeetUncertainties.

在我看来，我们只能同意Krueger文章的副标题，它抓住了问题的本质，那就是：&'不可解兄'啊，遇上了'不确定'弟&！

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。