复变量Lewy方程的广义解和古典解

在广义函数空间讨论了复变量Lewy方程δu/δz+izδu/δt=1/2F(z,z,t)广义解的存在性,获得了广义解的表达式.Lewy方程δu/δz+izδu/δz=1/2f(t)当f(t)仅为连续函数时,此解还是在区域D内的古典解,且证明了存在f(t)∈C∞(R),但在区间[-T,+T]处处不解析,却有在R3的C∞解.     

多元函数极限的一种求法

把多元函数极限的判断及求法转化为一元函数极限的判断及求法。将点(x0，y0，z0)的某去心邻域内的点(x，y，z)用向量(x-x0，y-y0，z-z0)的方向余弦及变量t表示为(x0 tcosα，y0 tcosβ，z0 tcosγ)，使多元函数f(x，y，z)转化为含自变量t的一元函数f(x0 tcosα，y0 tcosβ，z0 tcosγ)，且给出了定理及相应的推论，并给予证明。得出若t→0时，(x0 tcosα，y0 tcosβ，z0 tcosγ)→A是与α，β，γ取值无关的常数，则f(x，y，z)→A((x，y，z)→(x0，y0，z0))；若A与α，β，γ取值有关，则(x，y，z)→(x0，y0，z0)时f(x，y，z)的极限不存在。     

一类由Hadamard乘积定义的函数子类

设p为正整数,A(p)表示单位圆盘内形如,f(z)=Zp 8∑k=p 1akzk的解析函数全体,对给定的复常数λ≠-p及f(z)∈A(p),用Jλf(z)=hλ*f(z)定义算子Jλ,其中hλ(z)=8∑k=pp λ/k λzk,得出当Jλf(z)∈R(p)(a)(0≤α＜p)时,必存在r0,使得在|z|＜r0内,f(z)∈Rn(p)(β),其中0≤β＜P.     

涉及导数和分担值的全纯函数的正规定则

研究了全纯函数的正规性,推广了一个全纯函数族的正规定则,得到了涉及导数和分担值的全纯函数正规性的一个结果,即:设F是区域D上的一族全纯函数,且h(z)为D上的全纯函数,若对于任意的f(z)∈F,f(z)的零点重级至少为k,当h(z)≠0时,有f(z)=0|f(k)(z)|=h(z)|f(k+1)(z)|≤c(c为正数),则F在D上正规.     

Carleson测度与一致有界特征函数

UBC类与UBC_0类函数分别是BMOA类与VMOA类函数的亚纯推广。我们知道,对单位圆盘上的每一个解析函数f(z),f(z)∈BMOA当且仅当(1-|z|~2)|f′(z)|~2dxdy是Carleson测度;f(z)∈VMOA当且仅当(1-|z|~2)|f′(z)|2dxdy是消失Carleson测度。本文我们证明,对单位圆盘上的亚纯函数f(z),f(z)∈UBC_0当且仅当(1-|z|~2)f~(#2)(z)dxdy是消失Carleson测度;若f(z)∈N,则f(z)∈UBC当且仅当(1-|z|~2)f~(#2)(z)dxdy是Carleson测度;其中f~#(z)△=|f′(z)|/(1+|f(z)|~2)。     

Cauchy-Stieltjes积分乘子的半径增长(英文)

讨论了Cauchy-Stieltjes积分乘子的半径增长性质,得到如果f(z)∈μα,β,且∫π0ω(x)/x(β-α)+1dx+∞,则f(reiθ)有界(0≤r1).     

关于星象积分算子的星象阶数

<正>§1 引言及引理 设f(z)=z+∑a_nz_n在单位圆E: |z|<1内正则单叶,记其全体为S,对于ρ<1,Z∈E,记 s*(ρ)={f(z):f(z)∈S,且Re(zf'(z)/f(z))>ρ}, K(ρ)={f(z):f(z)∈S,且Re(1+(zf'(z)/f'(z)))>ρ},分别称S*(ρ),K(ρ)为ρ级星象函数类和ρ级凸象函数类。 若p(z)在E中解析,且满足p(o)=1,Rep(z)>0,记其全体为T。 作者已经证明     

数学奥林匹克高中训练题(46)

第一试 一、选择题(每小题6分,满分36分) 1.设集合 s=f(z,y)1 z一百1 y。为奇数,z,y E R}, T={(z,y)1 sin(2丁clz)一sin(7cy。)= COS(2丌z)一COS(Try。),‘z,∥E R}.则S与T的关系是( ). (A)S(==T (B)TCS (C)S=T (D)Sn T=黟 2.已知a∈(0,引^=(tan口)～心=(tan口)。‘。,t3:(cot d)‘“。,t4=(COt口)。‘“.则t。、t 2、t 3、t。的大小关系是( ). (A)t1相似文献   

函数的C-拟凸性

给出了在存在t0∈(0,1)满足f(t0x1 (1-t0)x2)∈y-C,for y∈E,f(x1),f(x2)∈y-C,的条件下函数f具有C-拟凸性的充分必要条件和一些相应的结果。     

“经济数学基础”学习导引(二)

第四章多元函数微分学一、主要教学内容1.多元函数的基本概念主要是二元函数,其概念的要素还是对应关系与定义域,二元函数的定义域是平面上的某个区域,对应关系一般表示为:z=f(x,y) (x,y)∈D例如,设 z=f(x,y)=sin(x y)则 f(0,0)=sin(0 0)=sin0=0f(π/2,π/2)=sin(π/2 π/2)=sin=0f(t,s)=sin(t s)2.偏导数与全微分设 z=f(x,y),则     

Western and Eastern culture differences in commercial field

The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.     

汉字倒说

汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。     

风的曲线

Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.     

团图为数的图中的闭团贯数

Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F.     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

钱生钱!

我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了     

Social and Cultural Influence on Word Meaning

Different nations have different social cultures, and the social culture of every nation is developing with the development of the nation, language is greatly influenced by social culture, which enables language to possess national and historical characteristics. Word is the smallest, independent, meaningful linguistic unit of language. It can well reflect the national and historical characteristics. From synchronic aspect, the social and cultural influence on word meaning is mainly embodied in conceptual and associative meanings of word. The incorrespondence of word meaning is a phenomenon that exists in both conceptual and associative meanings of word among different languages. From diachronic aspect, the development of social culture causes some changes of word meaning to some extent. Therefore, social culture plays a key role in vocabulary learning and mastery of a language.     

Inequalities for inscribed simplexes

The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex.