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1.
Lebesgue proved in 1940 that each 3-polytope with minimum degree 5 contains a 5-vertex for which the set of degrees of its neighbors is majorized by one of the following sequences(6, 6, 7, 7, 7), (6, 6, 6, 7, 9), (6, 6, 6, 6, 11)(5, 6, 7, 7, 8), (5, 6, 6, 7, 12), (5, 6, 6, 8, 10), (5, 6, 6, 6, 17)(5, 5, 7, 7, 13), (5, 5, 7, 8, 10), (5, 5, 6, 7, 27), (5, 5, 6, 6,∞), (5, 5, 6, 8, 15), (5, 5, 6, 9, 11)(5, 5, 5, 7, 41), (5, 5, 5, 8, 23), (5, 5, 5, 9, 17), (5, 5, 5, 10, 14), (5, 5, 5, 11, 13).We prove that each 3-polytope with minimum degree 5 without vertices of degree from 7 to 10 contains a 5-vertex whose set of degrees of its neighbors is majorized by one of the following sequences: (5, 6, 6, 5, ∞), (5, 6, 6, 6, 15), and (6, 6, 6, 6, 6), where all parameters are tight.  相似文献   

2.
3.
Book reviews     
L.N. TREFETHEN and D. BAU, III,Numerical Linear Algebra,SIAM, Philadelphia, 1997G.-C. ROTA,Indiscrete Thoughts,Birkhäuser, Boston, 1997D.E. KEYES, A. SAMEH and V. VENKATAKRISHNAN, eds.Parallel Numerical Algorithms,Kluwer, Dordrecht, 1997A. KIRSCH,An Introduction to the Mathematical Theory of Inverse Problems,Springer, New York, 1996L.F. SHAMPINE, R.C. ALLEN, Jr. and S. PRUESS,Fundamentals of Numerical Computing,Wiley, New York, 1997C.W. UEBERHUBERNumerical Computation, 2 vols.Springer, Berlin, 1997W.G. McCALLUM et al.Multivariate Calculus,Wiley, New York, 1997ZHI-QUAN LUO, JONG-SHI PANG and D. RALPH,Mathematical Programs with Equilibrium Constraints,Cambridge University Press, Cambridge, 1996P.R. POPIVANOV and D.K. PALAGACHEV,The Degenerate Oblique Derivative Problem for Elliptic and Parabolic Equations,Akademie Verlag, Berlin, 1997  相似文献   

4.
半质环的交换性条件   总被引:2,自引:0,他引:2  
傅昶林  郭元春 《数学学报》1995,38(2):242-247
本文对满足可变恒等式的半质环在某种有界条件下给出了一个判断环R交换性的简便准则,使文献[2-27]中所有相应结果均成为其直接推论.此外,对不限有界的情况,也得到较为广泛的结论.  相似文献   

5.
We consider the three dimensional Cauchy problem for the Laplace equation uxx(x,y,z)+ uyy(x,y,z)+ uzz(x,y,z) = 0, x ∈ R,y ∈ R,0 z ≤ 1, u(x,y,0) = g(x,y), x ∈ R,y ∈ R, uz(x,y,0) = 0, x ∈ R,y ∈ R, where the data is given at z = 0 and a solution is sought in the region x,y ∈ R,0 z 1. The problem is ill-posed, the solution (if it exists) doesn't depend continuously on the initial data. Using Galerkin method and Meyer wavelets, we get the uniform stable wavelet approximate solution. Furthermore, we shall give a recipe for choosing the coarse level resolution.  相似文献   

6.
给出了最佳参数α_1,α_2,α_3,β_1,β_2,β_3∈R,使得双向不等式α_1Q(a,b)+(1-α_1)G(a,b)0且a≠b成立.其中A(a,b)=(a+b)/2,H(a,b)=2ab/(a+b),G(a,b)=(ab)~(1/2),Q(a,b)=((a~2+b~2)/2)~(1/2),C(a,b)=(a~2+b~2)/(a+b),T(a,b)=2/π∫_0~(π/2)(a~2cos~2t+b~2sin~2)~(1/2)tdt分别是两个正数a和b的算术平均,调和平均,几何平均,二次平均,反调和平均和Toader平均.  相似文献   

7.
BOOK REVIEWS     
Book reviewed in this article: The Origin of the Carolina Bays , by Douglas Johnson. A Guide to Naval Aviation , by Lt. Wallace W. Elton, USNR; Lt. Alfred H. Driscoll, USNR; Lt. Robert N. Burchmore, USNR; and Lt. Gray B. Larkum, USNR. Mathematics for Navigators , by Delwyn Hyatt, Commander, USN, (Ret.) and Bennett M. Dodson, Commander, USNR. The Text -Activity Books . Elementary Topography and Map Reading , by Samuel L. Greitzer. Earth Science , A Physiography, by Gustave L. Fletcher. Shopwork , by Edward C. Wicks, Instructor of Industrial Arts, Morristown High School, New Jersey, John Poljacik, Jr., Instructor of Industrial Arts, Morrislown High School, and John Ellberg, author of Tales of A Rambler. Shop Practice , by William J. Kennedy. Plane Trigonometry and Statics , by Norman Miller. The Story of Flying , by Archibald Black. Electricity for Everyone , by Joseph R. Lunt, late Professor of Science at Rhode Island College of Education, and William T. Wyman. Air Navigation for Beginners , A Ground School Primer for Aerial Navigators , by Scott G. Lamb, B.S., M.S. Essentials of Algebra (Complete Second Year Course ), by Walter W. Hart. Solid Geometry , by F. Eugene Seymour, Supervisor of Mathematics, New York State Department of Education, and Paul James Smith, Head of Department of Mathematics, East High School, Rochester, New York. Modern Science Series , by Charles E. Dull. Organic Chemistry , by C. W. Porter and T. D. Stewart. Man's Physical Universe , by Arthur Talbot Bawden. Man and His Physical Universe , by Frank Covert, Jean Ezra Clarence Harrah, and Fred Louis Herman. Elementary Electricity , by Edgar P. Slack.  相似文献   

8.
Zusammenfassung In der folgenden Liste sollen einige häufig vorkommende Differentialoperatoren und ihre Fundamentallösungen in der Art einer Integraltafel zusammengefaßt werden. Dabei ist zu beachten, daß Fundamentallösungen im allgemeinen (d. h. ohne Zusatzbedingungen) nicht eindeutig bestimmt sind. In den meisten Fällen sind Berechnungsverfahren zur Herleitung der angegebenen Fundamentallösungen skizziert. DAbei wurden sowohl neue Methoden (z. B. Regularisierung, Penalisierung, regularisierte Faltung: 3, 6, 8, 10, 15, 22, 23, 24, 28, 31, 38, 40, 44, 48, 50, 51, 52, 64, 65, 68, 69, 72, 73) als auch neue Fundamentallösungen (15, 16, 20, 22, 23, 24, 31, 68, 69, 70) angegeben, deren Berechnung im 1. Teil (Abschnitt 3) aus Platzgründen nicht aufgenommen wurde. Die Berechnung von Fundamentallösungen mittelspartieller Fourier- oder Laplacetrans-formation, oder durch Spezialisierung in gewissen allgemeinen, von F. J. Bureau oder G. Herglotz angegebenen Integralen wurde außer Betracht gelassen und wird nicht zitiert. Für die Operatoren 26, 66, 67, 71, 74 und 77 wurden keine Fundamentallösungen angeschrieben, da entweder die entsprechende Literatur nur auszugsweise zur Verfügung stand oder die Formeln zu umfangreich sind.
Summary Similar to a table of integrals the following table contains some frequently occurring differential operators and their fundamental solutions. However one has to pay attention to the fact, that fundamental solutions are not given uniquely (i.e. without assuming further conditions). In most cases you find methods to derive the listed fundamental solutions. We give new methods (e.g. regularization, penalization, regularized convolution: 3, 6, 8, 10, 15, 22, 23, 24, 28, 31, 38, 40, 44, 48, 50, 51, 52, 64, 65, 68, 69, 72, 73) as well as new fundamental solutions (15, 16, 20, 22, 23, 24, 31, 68, 69, 70), whose computation is not contained in part one (section 3) for lack of space. The derivation of fundamental solutions bypartial Fourier- or Laplace Transformation, or by specializing certain general integrals given by F. J. Bureau or G. Herglotz is not taken into account. For the operators 26, 66, 67, 71, 74 and 77 no fundamental solutions are given either for the corresponding reference being only partially available or the formulas being too long.
  相似文献   

9.
令K_4(i,j,k,l,m,n)表示两两三度点间的路长分别为i,j,k,l,m,n的K_4-同胚图.对6条路的长均大于1且有4条路的长相等其余两条路互不相等的K_4-同胚图的着色进行了研究,得到了一类色唯一的K_4-同胚图.  相似文献   

10.
如果两个v阶拉丁方L和M的重叠产生恰好r个不同的有序对,则称L和M是r-正交的.如果L还是M的(i,j,k)-共轭,则称L是(i,j,k)-共轭r-正交的,简记为(i,j,k)-r-COLS(v)((i,j,k)-r-conjugate orthogonal Latin square of order v),其中{i,j,k}={1,2,3}.本文研究(3,2,1)-r-COLS(v)的存在性问题.对于v 23,除去少数几个可能的例外值,本文给出关于(3,2,1)-r-COLS(v)的几乎完整的解.对于v23,如果r∈[v,v2]\{v+1,v+2,v+3,v+5,v+7,v2 1},除去可能的例外r=v2 3,都存在(3,2,1)-r-COLS(v).由于(3,2,1)-r-COLS(v)的存在性与(1,3,2)-r-COLS(v)的存在性是等价的,本文得到关于(1,3,2)-r-COLS(v)的同样结论.  相似文献   

11.
An L(d0,d2,...,dt)-labeling of a graph G is a function f from its vertex set V(G) to the set {0,1,..., k} for some positive integer k such that If(x) - f(y)l ≥di, if the distance between vertices x and y in G is equal to i for i = 1,2,...,t. The L(d1,d2,...,dt)-number λ(G;d1,d2,... ,dt) of G is the smallest integer number k such that G has an L(d1,d2,...,dr)- labeling with max{f (x)|x ∈ V(G)} = k. In this paper, we obtain the exact values for λ(Cn; 2, 2, 1) and λ(Cn; 3, 2, 1), and present lower and upper bounds for λ(Cn; 2,..., 2, 1,..., 1)  相似文献   

12.
Book reviews     
《Optimization》2012,61(6):859-868
Devroye, L.; L. Györfi: Nonparametric Density Estimation: the L1 View. John Wiley & Sons New York, Chichester, Brisbane, Toronto, Singapore 1985, XI, 356 p., £ 45.90, ISBN 0-471816469

Gericke, H.: Mathematik in Antike und Orient. Springer-Verlag Berlin, Heidelberg, New York, Tokyo 1984, 140.Abb., 4 Kartenskizzen, XII, 292 S., DNI 98,-, ISBN 3-540-11647-8

K. ITö (ed.) StochasticAnalysis. Proceedings of the Traniguchi Internationaloal Symposium on Stochastic Analysis, Katata and Kyoto, 1982. North-Holland Mathematical Library, Vol. 32, North-Holland Publishing Company, Amsterdam 1984, 488 pages, Dfl. 250.- ISBN 0-444-87588-3

Weizenbaum, J.: Die Macht der Computer und dic Ohnmaeht der Vernuutt, Suhrkamp Taschenbuch Wissenschaf't 274. Suhrkamp Verlag Frankfurt/M. 1978, 368 S., DM 16,-, ISBN 3-518-27874-6

Krylov, N.V.; R. Sh. Lipiser; A.A Novikov (eds.): Statistics and Control of Stochastic Processes. Steklov Seminar, 1984. Springer-Verlag Berlin, Heidelberg, New York, Tokyo 1985, XIII, 507 S., DM 198, -, ISBN 3.540-96101-1

Sachs, H. (ed.): Graphs, Hypergraphs and Applications. Proceedings of the Conference on Graph Theory held in Eyba, Oct. 1984.. 'I'eubner-Texte zur Mathematik 73 Teubner Verlagsgesellschaft Leipzig 1985, 224 S., 23,-M, ISBN 666275-5

Bhat, U. Narayan; Elements of Applied Stochastic Processes. 2. Ed. Jonoh Wilet & Sons New York, Chichester, Brisbane, Toronto, Singapore 1984, IX, 685 p., £ 52.00, ISBN 0-471-87826-X

Methods of Operations Research. Bd, 66. Verlag Anton Hain Meisenheim, Königstein 1985, 410 S., DM 120,-, ISBN 3..445..02400..6

Maier, T.: Intervall-Input-Ontput-Rechnung. Mathernat.ical Systems in Economics. 101. Verlag Anton Rain, Meisenheim GmbH InigiteinTs. 1985, X, 338 S., DM 72,-, ISBN 3-445-02399-9.

Sawaragi, Y.; H. Nakayama; T. Tanino: Theory of Multi-objective Optimization. Mathematics in Science and Engineering. 176. Academic Press Orlando, San Diego, New York, London, Toronto 1985, 320 pp., $ 48.00, ISBN 0-12-620370-9.

Krämer, W.: Trend in ökonometrischen Modellen. Mathematical Systems in Economics. 93. Athenaum/Hain Konigstein 1985, 172 S., DM 48,-, ISBN 3-445-02386-7.  相似文献   

13.
In this paper, we present a discrete model to illustrate how two pieces of information interact with online social networks and investigate the dynamics of discrete-time information diffusion model in three types: reverse type, intervention type and mutualistic type. It is found that the model has orbits with period 2, 4, 6, 8, 12, 16, 20, 30, quasiperiodic orbit, and undergoes heteroclinic bifurcation near 1:2 point, a homoclinic structure near 1:3 resonance point and an invariant cycle bifurcated by period 4 orbit near 1:4 resonance point. Moreover, in order to regulate information diffusion process and information security, we give two control strategies, the hybrid control method and the feedback controller of polynomial functions, to control chaos, flip bifurcation, 1:2, 1:3 and 1:4 resonances, respectively, in the two-dimensional discrete system.  相似文献   

14.
NANU Mathematical Institute, Kiev, Ukraine and MCS University, Lublin, Poland; NANU Mathematical Institute, Kiev, Ukraine and Bielefeld University, Germany. Translated from Funktsional'nyi Analiz i Ego Prilozheniya, Vol. 29, No. 3, pp. 51–55, July–September, 1995.  相似文献   

15.
胡迪鹤 《数学学报》1979,22(4):420-437
<正> 马氏过程的分析理论(这是主要指马氏过程的转移函数及其对应的半群的分析理论),是马氏过程基本理论的一个重要组成部分,对时齐的马氏过程的分析理论,不论其状态空间是可数的或一般的,国内外作者都进行过大量研究,得到过一系列结果.然而,对  相似文献   

16.
BOOK REVIEW     
Life Cycles: Reflections of an Evolutionary Biologist, John Tyler Bonner, Princeton University Press, 41 William Street, Princeton, New Jersey, 08540, 1993, 209 pp., or UK: Princeton University Press, Chichester, West Sussex, ISBN 0-691-03319-6  相似文献   

17.
We study the existence, uniqueness and asymptotic behavior, as well as the stability of a special kind of traveling wave solutions for competitive PDE systems involving intrinsic growth, competition, crowding effects and diffusion. The traveling waves are exclusive in the sense that as the variable goes to positive or negative infinity, different species are close to extinction or carrying capacity. We perform an appropriate affine transformation of the traveling wave equations into monotone form and construct appropriate upper and lower solutions. By this means, we reduce the existence proof to application of well-known theory about monotone traveling wave systems (cf. [A. Leung, Systems of Nonlinear Partial Differential Equations: Applications to Biology and Engineering, MIA, Kluwer, Boston, 1989; J. Wu, X. Zou, Traveling wave fronts of reaction-diffusion systems with delay, J. Dynam. Differential Equations 13 (2001) 651-687] and [I. Volpert, V. Volpert, V. Volpert, Traveling Wave Solutions of Parabolic Systems, Transl. Math. Monogr., vol. 140, Amer. Math. Soc., Providence, RI, 1994]). Then, by using spectral analysis of the linearization over the profile, we prove the orbital stability of the traveling wave in some Banach spaces with exponentially weighted norm. Furthermore, we show that the introduction of some weight is necessary in the sense that, in general, traveling wave solutions with initial perturbations in the (unweighted) space C0 are unstable (cf. [I. Volpert, V. Volpert, V. Volpert, Traveling Wave Solutions of Parabolic Systems, Transl. Math. Monogr., vol. 140, Amer. Math. Soc., Providence, RI, 1994] and [D. Henry, Geometric Theory of Semilinear Parabolic Equations, Lecture Notes in Math., vol. 840, Springer-Verlag, New York, 1981]).  相似文献   

18.
Book reviews     
《Optimization》2012,61(3-4):297-305
d'Alessandro, P., A Conical Approach to Linear Programming Scalar and Vector Optimization Problems, Gordon and Breach Science Publishers, Australia Canada China France Germany India Japan Luxembourg Malaysia The Netherlands Russia Singapore Switzerland Thailand United Kingdom 1997, 312 pp., ISBN 90- 5699-031-4.

Fang, S.-C., Rajasekera, J. R. and Tsao, H. S. J., Entropy Optimization and Mathematical Programming, Kluwer's International Series. Kluwer Academic Publishers, Boston London Dordrecht, 1997, pp. 343, US $120.00; ISBN 0-7923-9939-0.

Golshtein, E. G. and Tretyakov, N. V., Modified Lagrangians Monotone Maps in Optimization, John Wiley & Sons, New York Chicester Brisbane Toronto Singapore 1996,438 pp., £55.00, ISBN 0-471-54821-9.

Hoffmann, K.-H., Leugering, G. and Troltzsch, F. (Eds.), Optimal Control of Partial Differential Equations, International Confa-ence in Chemnitz, Germany, April 20-25, 1998; International Series of Numerical Mathematics ISNM, Vol. 133, Birkhauser Verlag AG, Basel*Boston-Berlin 1999, viii+323 pp., DM 188.00, ISBN 3-7643- 6151-4.  相似文献   

19.
Book Vignettes     
Freeman, Ira M., Light and Radiation. Calder, Nigel, Violent Universe: An Eyewitness Account of the New Astronomy. Glasstone, Samuel, The Book of Mars. Randall, Charles A. Jr., Extra-Terrestrial Matter. Willerding, Margaret F. and Hoffman, Stephen, Modern Intermediate Algebra. Cohen, David, O'Neill, Brian J., and Bailey, John E., Geology: Rocks and Mincrals. Are You Unique? Careers In—Accounting, Banking, Business, Economics, Engineering, Finance Law, Mathematics, Other Professions. 0–319–339, U. S. Government Printing Office, Washington, D. C. 1969.  相似文献   

20.
倪仁兴  余丽云 《数学学报》2010,53(3):477-488
对一致广义Lipschitz连续的逐次渐近Φ-强半压缩型有限算子簇,研究了一致光滑Banach空间中具误差的修正多步Noor迭代序列强收敛于该算子簇的公共不动点问题.作为所得结果的应用,得到了2007年Huang在相同空间框架中所建立的逼近具有有界值域的逐次Φ-强伪压缩算子的不动点具误差的修正Mann迭代和具误差的修正Ishikawa迭代两者的收敛是等价的这一结果,而且所用的方法不同于Huang.同时还改进和推广了Rhoades和Soltuz,Huang,Bu和Noor,Huang和Bu,Su,Yao,Chen和Zhou,Liu,Kim,Kim,Liu,Ni和Xu等人的近期相应结果.  相似文献   

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