On the Helly Number for Line Transversals to Parallel Triangles

We prove two results about the problem of finding the Helly number for line transversals to a family of parallel triangles in the plane: (1) If each three triangles of a family of parallel right triangles are intersected by an ascending (or a descending) line, then there is an ascending (or a descending) line that intersects all     

多目标模糊系数规划

在单目标模糊系数规划的理论基础上，对多目标模糊系数规划进行讨论，在以目标间的协调程度尽可能大为最优性条件的要求下提出多目标模糊系数规划最优解的定义，并给出一种可行的求解方法。     

Asymmetric borane reduction of achiral ketones mediated by a chiral oxazaborolidine derived from (−)-ephedrine

Asymmetric borane reduction of achiral ketones in the presence of a chiral oxazaborolidine derived from (−)-ephedrine yielded the corresponding alcohols in optical yields of 41 – 83 % ee.     

Worst allocations of policy limits and deductibles

In the literature, orderings of optimal allocations of policy limits and deductibles were established with respect to a policyholder’s preference. However, from the viewpoint of an insurer, the orderings are not enough for the purpose of pricing. In this paper, by applying the equivalent utility premium principle, we study worst allocations of policy limits and deductibles for an insurer, which give rise to the maximum fair premiums. Closed-form solutions are derived. Then we present a result concerning the optimality in a general risk-sharing scheme, by which we obtain optimal allocations for policyholders directly from worst allocations for an insurer. Several results in Cheung [Cheung, K.C., 2007. Optimal allocation of policy limits and deductibles. Insurance Math. Econom. 41, 382–391] are generalized here.     

Design of Broadband L-band Erbium Doped Fiber Amplifier

An 80 nm bandwidth long wavelength erbium-doped fiber amplifier using a seed light injection method is designed.It is shown that when the wavelength of the seed beam varies from 1520 nm to 1570 nm,the gain at 1610 nm increases and reaches maximum near 1553 nm and then decreases.The gain increases with the seed light power.With the seed light ,the long wavelength Erbium-doped fiber amplifier has 80 nm bandwidth (1570～1650 nm),30 dB gain and noise figure less than 5.0 dB.     

Two New Secoiridoid Glycosides from Tripterospermum chinense

Two new secoiridoid glycosides, tripterospermumcin A ( 1 ) and B ( 2 ), were isolated from the EtOH extract of the aerial parts of Tripterospermum chinense (Migo ) H. Smith , along with three known compounds, secologanin, secologanol, and sweroside. Their structures were established on the basis of UV, IR, MS, and extensive 1D‐ and 2D‐NMR analyses, as well as by literature comparison of spectroscopic data.     

一类不可分解Banach空间上线性算子的谱性质

给出一类不可分解的∑_e~1型Banach空间上线性算子(不一定有界)的谱结构,并讨论这种空间上生成C_0群或C_0半群的线性算子的有界性、特殊的谱性质和谱结构,还给出这种空间上闭算子是有界算子的一个充分条件。     

k＜1时Cartan-Hartogs域上的极值问题

本文讨论两种类型的极值问题,其中一种类型的极值问题可以认为是复平面上经典的Schwarz引理在高维的一个推广;另一种类型的极值是某空间上的度量,可以用来考虑域的双全纯等价分类问题．在本文中,k＜1时Cartan-Hartogs域与单位超球间的极值与极值映照被得到。     

序Banach空间中一类算子方程的可解性

利用改进的Mnch紧性条件,研究了一类算子方程Lx=Nx的解的存在性．本文结果并没有要求算子L和N的连续性．作为应用,讨论了右端项不连续的隐式椭圆偏微分方程的边值问题的解的存在性．