在S2或T2上HCMU的曲率的光滑性

HCMU是一种在Riemann面上带奇点的extremal度量．在面积和Calabi能量有界的情况下, HCMU的Gauss曲率是Riemann面上的连续函数．本文得到一个在球面上没有Gauss曲率鞍点的HCMU的明显表达式,并进一步证明了在球面或环面上HCMU的Gauss曲率光滑的充要条件是度量的所有奇点的角度都是整数．     

Theory stranded at the borders,or, Cultural Studies from the southern fringes

ABSTRACT

Isolating certain critical blind spots that one encounters in studying lifeworlds of the global South, this essay calls for: (1) a grasp of the irreducible singularity of each historical formation as an essential aspect of southern Cultural Studies, so that its lessons are not readily erased, dismissed as signs of failure, or bracketed as idiosyncratic exceptions to universalized standards; and (2) the recognition of volatile and illicit forms of popular agency—emerging in friction with the security-obsessed governmentality of the borderlands, the exclusionary institutions of civil society, and the normativities of citizenship—as legitimate heralds of a global political futurity.     

对锥形扩散器内紊流的数值仿真与分析

本文用DLR（近壁低雷诺数）型k-ε紊流模型·BFC（边界拟合曲线坐标变换）法对锥形扩散器内的紊流进行了数值仿真与分析。通过对数值仿真结果和实验结果的比较,分析不同模型常数组、模型函数组和时间步长对时均速度和紊流动能的影响。     

应用奇异性理论分析水电机组的振动稳定性

针对机组轴系由电磁作用激发的振动问题,应用奇异性理论进行稳定性分析。首先求得转迁集,进而计算由转迁集而划分出的不同区域内的曲线形状,并分析这些曲线的稳定性,最后给出总的分岔图。所得结论对水电机组的电磁参数设计有一定的帮助作用。     

一类带奇性的椭圆型方程的正解

通过山路引理,研究一类带奇性的椭圆型方程正解的存在性问题。利用变分方法,得出在α的某一条件下此方程存在正解。     

On Bifurcations of an Ordinary Differential Equation

1 IntroductionThe biforations of the following ordinal differentialequation with tWo-poaal bounce value condihonlllF(U,It) = U* p(u ~Uk) = 0, X E (0, n ),, (l)u(0) = u(O = 0, (2)was considered in Ref.[21, where p is a parameter,4 s k e Z .For every p, (l) together with (2) has a trivialsolution u = 0. Consider the linearized eqUationDuF(0,p)v = v' W = 0 (3)with the boundary value conditionv(0) = v(O = 0.Obviously, (3), together with (4) has nontrivial solutionsv =csinnx (c is an arbitrn…     

一类DIRICHLET外问题的边界元法

本文讨论Dirichlet外问题的边界元法 .给出了三维问题的一个数例以及它的一个特殊剖分 .     

S2上一类HCMU度量的存在性

HCMU度量是紧黎曼面上带奇点的extremal度量.研究它的存在性十分重要.通过研究Chen和Wu（Pacific J Math,2009,240（2）：267-288）给出的S²上HCMU度量存在的充分必要条件,证明当S²上至少有（N-1）个鞍点时,一定存在non-CSC HCMU度量,其中N是所有锥奇点的个数.     

Understanding narrative relations in teacher education

The use of stories in teacher education is ubiquitous; yet, the question regarding how stories help teachers make sense of their professional lives is more complex than it first appears. The authors draw from Adriana Cavarero's understanding of narrative relations as the political site where one's unique singularity is revealed in the desire to have one's story told. They compare her insights to Judith Butler's resignification of injurious speech, examining both positions as they apply to a beginning teacher's efforts to become the professional she admires. It is suggested to teacher educators that they use stories from practice to foreground the tension between a teacher's life and her life-story. By understanding the irresolvable tension of desire to have one's story told, a teacher has a better chance of recognising her own vulnerability and that of her students, and of teaching at the starting place of ethics.     

Reaction thrust of water jet for conical nozzles

Clear knowledge on the reaction thrust of water jet is valuable for better design of water jet propulsion system. In
this paper, theoretical, numerical and experimental studies were carried out to investigate the effects of the nozzle geometry
as well as the inlet conditions on the reaction thrust of water jet. Comparison analyses reveal that the reaction thrust has a
direct proportional relationship with the product of the inlet pressure, the square of flow rate and two-thirds power exponent
of the input power. The results also indicate that the diameter of the cylinder column for the conical nozzle has great influence
on the reaction thrust characteristics. In addition, the best values of the half cone angle and the cylinder column length exist
to make the reaction thrust reach its maximum under the same inlet conditions．