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1.
We consider the quasilinear system
where , V and W are positive continuous potentials, Q is an homogeneous function with subcritical growth, with satisfying . We relate the number of solutions with the topology of the set where V and W attain it minimum values. We consider the subcritical case γ = 0 and the critical case γ = 1. In the proofs we apply Ljusternik-Schnirelmann theory. The second author was partially supported by FEMAT-DF  相似文献   

2.
One of the main results of the present article is as follows Theorem. Let v: Ω → ? be a C1-smooth function on a domain Ω ? ?2. Suppose that Int?v(Ω) = ?. Then, for every point z ∈ Ω, there is a straight line L ? z such that ?v ≡ const on the connected component of the set L ? Ω containing z.Also, we prove that, under the conditions of the theorem, the range of the gradient ?v(Ω) is locally a curve and this curve has tangents in the weak sense and the direction of these tangents is a function of bounded variation.  相似文献   

3.
关于代数体函数的重值   总被引:1,自引:0,他引:1  
何育赞 《数学学报》1979,22(6):733-742
<正> 关于亚纯函数或全纯函数的重值问题,首先为卡拉德峨多利(Caratheodory)、蒙德耳(Montel)所研究,并获得重要的结果,其后G.伐理隆(Valiron)、R.奈望利纳(Nevanlinna),以及较近熊庆来等就重值对值分布的影响进行了进一步的研究,获得新结的果.  相似文献   

4.
本文利用Hausdorff非紧测度、分数阶的微积分理论和Kakutani不动点定理,研究了满足条件z(0)=z0,z(1)=λcI0+γ+z(η)=λ∫0η(η-s)γ-1/Γ(γ)z(s)ds的广义Bagley-Torvik型分数阶微分包含cDv1 z(t)-ac Dv2 Z(t)∈F(t,z(t)),t∈(0,1)解的存在性.其中1 0,a和λ是给定的常数.  相似文献   

5.
An abstract Riemannian metric ds²= Edu² + 2Fdudv + Gdv² is given in (u, v) ∈ [0, 2&Pi] × [-&delta, &delta] where E, F, G are smooth functions of (u, v) and periodic in u with period 2&Pi. Moneover K|_{v=0} = 0. K_r|_{v=0} ≠ 0. when> K is the Gaussian curvature. We imbed it semiglobally as the graph of a smooth surface x = x(u, v ), y = y(u, v), z = z(u, v) of R³ in the neighborhood of v = 0. In this paper we show that, if [K_rΓ²_{11}]_{v=0}, and three compatibility conditions are satisified, then there exists such an isometric imbedding.  相似文献   

6.
7.
Let A be a free alternative Φ-algebra, where Φ is an associative commutative ring with 1, containing 1/6, and g(y, z, t, v, x, x)=2[J_({[y, z], t, x}_, x, v)+J_({[y,x], z, x}_, t, v)], where [x, y]=xy−yx, J_(x, y, z)=[[x, y], z]+[[z, x], y]+[[y, z], x], {x, y, z}_=J_(x, y, z)+3[x, [y, z]]. We construct trivial nuclear ideals of A, that is, nonzero ideals with zero multiplication, lying in the associative center of A. In particular, it is shown that if G and B are fully invariant ideals of A on k≥7 free generators, generated by a function g and by double commutators, respectively, then GB+BG is a nuclear ideal of A. This implies that an unmized alternative algebra satisfies GB=BG=0. If an unmixed algebra is finitely generated, then G=0. In addition, we prove that if R is an unmixed solvable alternative algebra then (RN)2=0 for some N. Translated fromAlgebra i Logika, Vol. 36, No. 1, pp. 97–115, January–February, 1997.  相似文献   

8.
This paper considers a generalization of an integral introduced by S. Ramanujan in his third notebook. Ramanujan’s integral is itself a version of the dilogarithm,
We prove various functional equations and properties of the generalized integral. 2000 Mathematics Subject Classification Primary–33B30  相似文献   

9.
One considers the class S of functions, regular and univalent in ¦Z¦<1 and normalized by the expansion f(z)=Z + C2Z2 +.... By the logarithmic coefficients of the function f (z) S one means the coefficients of the expansion Earlier, the author had formulated the following conjecture: for any function f(z) S, for each z (0,1) one has the inequality In this paper this conjecture is proved for spiral-shaped functions and for functions from S with real coefficients and under some additional assumptions.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 125, pp. 135–143, 1983.  相似文献   

10.
用Langer变换和Olver变换求得一类具有转向点问题的n阶近似解:y(x)=v(x)ψ(x),其中ψ=λ12-14×(x2-1)14,2332=-λx∫11-τ2dτ,v(z)=A(z,λ)ξ(λ23z)+B(z,λ)'ζ(λ23z).并探讨了其特征值问题,得到λn=4n+1112,n=0,1,2….由此给出了该类问题的解的一般性结论.  相似文献   

11.
Summary A classical result (see R.Nevanlinna, Acta Math.,58 (1932), p. 345) states that for a second-order linear differential equation, w + P(z) w + Q(z) w=0, where P(z) and Q(z) are polynomials, there exist finitely many rays, arg z=j, for j=1,..., m, such that for any solution w=f(z) 0 and any > 0, all but finitely many zeros off lie in the union of the sectors ¦ arg z - j¦ < for j=1,..., m. In this paper, we give a complete answer to the question of determining when the same result holds for equations of arbitrary order having polynomial coefficients. We prove that for any such equation, one of the following two properties must hold: (a) for any ray, arg z=, and any > 0, there is a solution f 0 of the equation having infinitely many zeros in the sector ¦arg z - ¦ <, or (b) there exist finitely many rays, arg z=j, for j= 1,..., m, such that for any >0, all but finitely many zeros of any solution f 0 must lie in the union of the sectors ¦ arg z - j¦ < for j=1, ..., m. In addition, our method of proof provides an effective procedure for determining which of the two possibilities holds for a given equation, and in the case when (b) holds, our method will produce the rays, arg z=j. We emphasize that our result applies to all equations having polynomial coefficients, without exception. In addition, we mention that if the coefficients are only assumed to be rational functions, our results will still give precise information on the possible location of the bulk of the zeros of any solution.This research was supported in part by the National Science Foundation (DMS-84-20561 and DMS-87-21813).  相似文献   

12.
Let \[f(z) = z + \sum\limits_{n = 1}^\infty {{a_n}{z^n} \in S} {\kern 1pt} {\kern 1pt} {\kern 1pt} and{\kern 1pt} {\kern 1pt} {\kern 1pt} \log \frac{{f(z) - f(\xi )}}{{z - \xi }} - \frac{{z\xi }}{{f(z)f(\xi )}} = \sum\limits_{m,n = 1}^\infty {{d_{m,n}}{z^m}{\xi ^n},} \], we denote \[{f_v} = f({z_v})\] , \[\begin{array}{l} {\varphi _\varepsilon }({z_u}{z_v}) = {\left| {\frac{{{f_u} - {f_v}}}{{{z_u} - {z_v}}}} \right|^\varepsilon }\frac{1}{{(1 - {z_u}{{\bar z}_v})}},\g_m^\varepsilon (z) = - {F_m}(\frac{1}{{f(z)}}) + \frac{1}{{{z^m}}} + \varepsilon {{\bar z}^m}, \end{array}\], where \({F_m}(t)\) is a Faber polynomial of degree m. Theorem 1. If \[f(z) \in S{\kern 1pt} {\kern 1pt} {\kern 1pt} and{\kern 1pt} {\kern 1pt} {\kern 1pt} \sum\limits_{u,v = 1}^N {{A_{u,v}}{x_u}{{\bar x}_v} \ge 0} \] and then \[\begin{array}{l} \sum\limits_{u,v = 1}^N {{A_{u,v}}{\lambda _u}{{\bar \lambda }_v}} {\left| {\frac{{{f_u} - {f_v}}}{{{z_u} - {z_v}}}} \right|^\varepsilon }\exp \{ \alpha {F_l}({z_u},{z_v})\} \ \le \sum\limits_{u,v = 1}^N {{A_{u,v}}{\lambda _u}{{\bar \lambda }_v}} \varphi _\varepsilon ^\alpha ({z_u}{z_v})l = 1,2,3, \end{array}\], where \[\begin{array}{l} {F_1}({z_u},{z_v}) = \frac{1}{2}\sum\limits_{n = 1}^\infty {\frac{1}{n}} g_n^\varepsilon ({z_u})\bar g_n^\varepsilon ({z_v}),\{F_2}({z_u},{z_v}) = \frac{1}{{1 + {\varepsilon _n}R{d_{n,n}}}}Rg_n^\varepsilon ({z_u})Rg_n^\varepsilon ({z_v}),\{F_3}({z_u},{z_v}) = \frac{1}{{1 - {\varepsilon _n}R{d_{n,n}}}}Rg_n^\varepsilon ({z_u})Rg_n^\varepsilon ({z_v}). \end{array}\] The \[F({z_u},{z_v}) = \frac{1}{2}{g_1}({z_u}){{\bar g}_2}({z_v})\] is due to Kungsun. Theorem 2. If \(f(z) \in S\) ,then \[P(z) + \left| {\sum\limits_{u,v = 1}^N {{A_{u,v}}{\lambda _u}{{\bar \lambda }_v}} {{\left| {\frac{{{f_u} - {f_v}}}{{{z_u} - {z_v}}}\frac{{{z_u}{z_v}}}{{{f_u}{f_v}}}} \right|}^\varepsilon }} \right| \le \sum\limits_{u,v = 1}^N {{\lambda _u}{{\bar \lambda }_v}} \frac{1}{{1 - {z_u}{{\bar z}_v}}}\], where \[\begin{array}{l} P(z) = \frac{1}{2}\sum\limits_{n = 1}^\infty {\frac{1}{n}} {G_n}(z),\{G_n}(z) = {\left| {\left| {\sum\limits_{n = 1}^N {{\beta _u}({F_n}(\frac{1}{{f({z_u})}}) - \frac{1}{{z_u^n}})} } \right| - \left| {\sum\limits_{n = 1}^N {{\beta _u}z_u^n} } \right|} \right|^2}, \end{array}\], \(P(z) \equiv 0\) is due to Xia Daoxing.  相似文献   

13.

For a new axiomatization, with fewer and weaker assumptions, of binary rank-dependent expected utility of gambles the solution of the functional equation


is needed under some monotonicity and surjectivity conditions. We furnish the general such solution and also the solutions under weaker suppositions. In the course of the solution we also determine all sign preserving solutions of the related general equation


  相似文献   


14.
Let
$ P\left( z \right) = \sum\limits_{v = 0}^n {c_v z^v } $ P\left( z \right) = \sum\limits_{v = 0}^n {c_v z^v }   相似文献   

15.
任福尧 《数学学报》1958,8(2):181-189
<正> 1.设 p 次对称函数(?)在单位圆|z|<1中是正则的单叶的,此种函数的全体成一函数族 S_p.当p=1时,简讯 S_1为 S.设ω=f(z)∈S_p 映照|z|<1于 W 面上时,其像关于原点成星形,此种 f(z)成 S_p 之一子族S_p.设 f(z)∈S_p,  相似文献   

16.
Let W (z) and M(z) be v-valued and k-valued algebroidal functions respectively,(θ) be a b-cluster line of order ∞ (or ρ(r)) of W (z) (or M(z)).It is shown that W (z) ≡ M(z) provided E(a j ,W (z)) = E(a j ,M(z)) (j = 1,...,2v + 2k + 1) holds in the angular domain Ω(θ- δ,θ + δ),where b,a j (j = 1,...,2v + 2k + 1) are complex constants.The same results are obtained for the case that (θ) is a Borel direction of order ∞ (or ρ(r)) of W (z) (or M(z)).  相似文献   

17.
The classical result of Landau, establishing the radius of the largest circle, in which, for any function f(z)R, where R is the class of regular functions w=f(z)=z+c2z2+..., in¦z¦<1, ¦f(z)¦相似文献   

18.
On the elements of the ring of residues modulo v (zτ v, 3τ v) we construct cyclic PBIB-designs with τ(v)-1 classes of connectedness, where τ(v) is the number of divisors of v. We prove the existence of cyclic BIB-designs with parameters b, v, r, k, and λ such that: 1) λ=k (and also λ=k/2 if k is even), k≥4, and (k-1) ¦ (p-1) for each prime divisor p of the number v; 2) λ=(k?l)/2, k odd, k≥3, k ¦ (p?1) for each prime divisor p of the number v.  相似文献   

19.
本文证明了如下结果:对于有穷正级亚纯代数体函数,一定存在一条奇异方向L∶arg z=θ0(0≤θ0<2π),使得对于任意δ∈(0,π/2),在角域Δ(θ0,δ)内,对任意复数a,对任意ε>0,有∑i1|zi(a;Δ(θ0,δ))|σ=∞(σ等于ρ或ρ-ε)至多有2v个例外a值.  相似文献   

20.

We consider two classes of systems of partial differential equations of first order. One consists of generalized Stokes-Beltrami equations $ Aw_z = w^*_z $ , $ \lambda Bw_{\bar z} -w^*_{\bar z} $ with square matrices A and B and a scalar factor u . The other may be written in matrix notation as $ v_{\bar z} = c{\bar v} $ where c denotes a square matrix. This system is known as a Pascali system. Both systems are in close connections to certain systems of second order for which the solutions can be represented using particular differential operators. On the basis of these relations we give the solutions of the first order systems explicitly.  相似文献   

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