关于二次型非线性盈亏平衡的分析

盈亏平衡分析目的是为了降低来自市场的不确定性因素给投资人带来的风险，而非线性盈亏平衡分析更接近市场经济条件下投资项目收入与成本的实际情况，通过对其中最为常见的二次型非线性盈亏平衡分析中所涉及的收入曲线和成本曲线的各种组合的分析，为一个一般性结论提供了依据，而该结论能在二次型非线性盈亏平衡分析中寻找盈亏平衡点提供方便。     

新一类广义强非线性拟-似变分包含问题

在Hilbert空间研究了新一类广义强非线性拟—似变分包含问题，给出了其解的存在唯一性证明，所得结果改进和推广了文献中的一些已知结果。     

爱因斯坦和玻尔的科学创新方法论原则

本文在深入研究、比较爱因斯坦和玻尔科学创新方法及其特点的基础上,揭示了科学创新活动应当遵循的方法论原则,即哲学思想渗透原则、逻辑思维与非逻辑思维相结合原则和思想实验与物质实验相结合原则。     

变形双重介质分形油藏渗流流动分析

研究了变形双重介质分形油藏渗流问题的压力不稳定响应 ,考虑了储层的双重介质特征和分形特征以及应力敏感地层中介质的变形问题 ,建立了新的应力敏感地层双重分形介质数学模型 ,包括只有裂缝发生形变和裂缝与岩石同时发生形变时定产量生产的两类数学模型。渗透率依赖于孔隙压力变化的流动方程是强非线性的 ,故采用数值方法求解了这些数学模型。探讨了分形参数、变形参数和双重介质参数变化时压力的变化规律 ,给出了典型的压力曲线图板。这些结果可用于试井分析。     

边界单元法三维应力分析计算程序

以三维弹性力学问题的基本解 (Kelvin解 )为基础开发了边界单元法三维弹性应力分析计算程序 ,并对其进行了验证。结果表明 ,该程序可用来求解三维弹性应力问题 ,尤其适用于三维应力集中问题。程序中采用动态分配内存 ,自动选点积分 ,并利用分块解法求解方程组 ,有效地节省了计算机资源 ,扩大了求解问题的规模。     

Structural and Chemical Diversity of TI-Based Cuprate Superconductors

The first TI一based euprate supereonduetor,TI一Ba-Cu一(),was diseovered by 2.2.Sheng and A.M.Hermann仁1〕. TI beeomes supereondueting at 2.38 K.NumerousTI eompounds and alloys are supereondueting.TIMo6Ses has the highest transition temperature of1 2.2 K among all non一euprate Tl eontaining alloyand eompound supereonduetors.Before thediseovery of the euprate supereonduetors,some TIeontaining oxide supereonduetors were found,among whieh TI。.3W()3 has the highest transitiontemPerature,2.14 K. Sinee the diseovery of TI euPratesuPereonduetors,two distinet families have beenidentified.Soon after the diseovery of TI一Ba一Cu-(),supereonduetivity was eonfirmed in TI一Ba一Ca-Cu一()samples.The ehemieal eompositions anderystal struetures of those eompounds were workedout as T12BaZCu()6,T12BaZCaCuZ()。,andT12BaZCaZCu3OI。[2〕.This 15 the first family of TIeuPrate supereonduetors,whieh features two TIatoms in eaeh ehemieal formula.     

Shakedown Analysis of 3-D Structures Using the Boundary Element Method Based on the Static Theorem

The static shakedown theorem was reformulated for the boundary element method (BEM) rather than the finite element method with Melan‘s theorem, then used to develop a numerical solution procedure for shakedown analysis. The self-equilibrium stress field was constructed by a linear combination of several basis self-equilibrium stress fields with undetermined parameters. These basis self-equilibrium stress fields were expressed as elastic responses of the body to imposed permanent strains obtained using a 3-D BEM elastic-plastic incremental analysis. The lower bound for the shakedown load was obtained from a series of nonlinear mathematical programming problems solved using the Complex method. Numerical examples verified the precision of the present method.     

聚丙烯无卤阻燃复合材料的制备及性能研究

以聚丙烯(PP)为基料、Mg(OH)2／Al3/P为复合阻燃剂。通过熔融共混制备PP无卤阻燃复合材料。对材料的阻燃性能和力学性能进行了测定。实验结果表明：当PP：Mg(OH)2：Al(OH)2：P为100：50：50：5时，混合物的阻燃性能和力学性能均能满足使用要求。填加纤维状Mg(0H)2的材料要比填加球状Mg（OH)2体系的拉伸强度优异。     

冻土墙墙体时空扩展过程中热能消耗的有限元分析

用于人工冻土墙形成过程相关计算的Sanger—Sayles经验公式是，Fourier热传导方程在单值热物理参数轴对称条件下的求解结果，对结构形成过程中冻结管吸热的计算采用了不合理的温度分布假设，计算结果不能令人满意。运用有限元分析程序，完成了对热物理参数非线性变化土体材料的人工冻结过程的计算分析，模拟了冻土墙时空扩展过程，研究了土体内的温度分布以及能量消耗等问题，在此基础上推导出的关于冻结过程的能量消耗计算的一般形式，对人工冻土墙的工程设计具有重要的指导意义。     

Multisymplectic five-point scheme for the nonlinear wave equation

In this paper, we introduce the multisymplectic structure of the nonlinear wave equation, and prove that the classical five-point scheme for the equation is multisymplectic. Numerical simulations of this multisymplectic scheme on highly oscillatory waves of the nonlinear Klein-Gordon equation and the collisions between kink and anti-kink solitons of the sine-Gordon equation are also provided. The multisymplectic schemes do not need to discrete PDEs in the space first as the symplectic schemes do and preserve not only the geometric structure of the PDEs accurately, but also their first integrals approximately such as the energy, the momentum and so on. Thus the multisymplectic schemes have better numerical stability and long-time numerical behavior than the energy-conserving scheme and the symplectic scheme.