检索结果-南通市图书馆

A lower bound on the total signed domination numbers of graphs

在线全文

学校读者我要写书评

暂无评论

Science china mathematics 2007年第8期50卷 1157-1162页

作者： Xin-zhong LU department of mathematics,zhejiang normal university,jinhua 32.004,china department of mathematics Zhejiang Normal University Jinhua 321004 China

Let G be a finite connected simple graph with a vertex set V (G) and an edge set E(G). A total signed domination function of G is a function f : V (G) ∪ E(G) → {?1, 1}. The weight of f is w(f) = Σ x∈V(G)∪E(G) f(x). For an element x ∈ V (G) ∪ E(G), we define $f[x] = \sum\nolimits_{y \in N_T [x]} {f(y)} $ . A total signed domination function of G is a function f : V (G) ∪ E(G) → {?1, 1} such that f[x] ? 1 for all x ∈ V (G) ∪ E(G). The total signed domination number γ s * (G) of G is the minimum weight of a total signed domination function on G.In this paper, we obtain some lower bounds for the total signed domination number of a graph G and compute the exact values of γ s * (G) when G is C n and P n .

关键词： total signed domination function total signed domination number 26A33

Codimension 3 nonresonant bifurcations of homoclinic orbits with two inclination flips

在线全文

学校读者我要写书评

暂无评论

Science china mathematics 2005年第2期48卷 248-260页

作者： SHUI Shuliang & ZHU Deming College of mathematics and Physics, zhejiang normal university, jinhua 32.004, china department of mathematics, East china normal university, Shanghai 200062, china 1. College of mathematics and Physics Zhejiang Normal University 321004 Jinhua China 2. department of mathematics East China Normal University 200062 Shanghai China

Homoclinic bifurcations in four-dimensional vector fields are investigated by setting up a local coordinate near a homoclinic orbit. This homoclinic orbit is principal but its stable and unstable foliations take inclination flip. The existence, nonexistence, and uniqueness of the 1-homoclinic orbit and 1-periodic orbit are studied. The existence of the two-fold 1-periodic orbit and three-fold 1 -periodic orbit are also obtained. It is indicated that the number of periodic orbits bifurcated from this kind of homoclinic orbits depends heavily on the strength of the inclination flip.

关键词： bifurcation, homoclinic orbit, non-resonance, inclination flip, 1-periodic orbit.

Synthesis and Crystal Structure of CoCl(ieaa)(C_(10)H_7-ieai)(C_(10)H_7NH_2)

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2002年第1期21卷 22-25页

作者： FENG Yun-Long (department of Chemistry, zhejiang normal university jinhua 231004,china) department of Chemistry Zhejiang Normal University Jinhua 231004

The title complex CoCl(ieaa)(C10H7-ieai)(C10H7NH2), C32H32ClCoN4O7, Mr= 679.00; (ieaa- and C10H7-ieai- are the anions of isonitrosoethylacetoacetate and its N-a- naphthylamine derivative of Schiff base, respectively, C10H7NH2 is a-naphthylamine), crystallizes in the monoclinic system, space group P21/n with a=11.846(2), b=23.912(5), c=12.783(3)? b=116.54(3), V=3239(1)?, Dc=1.392g/cm3, F(000)=1408, Mr=679.00, m(MoKa)=0.665mm-1, Z=4, final R=0.0584 and wR=0.1388 for 4177 observed reflections (I ≥ 2s(I)). A nitrogen atom of the ieaa- ligand and two nitrogen atoms of the C10H7-ieai- ligand define one of the triangular faces in the distorted octahedral geometry about the cobalt atom. The title complex contains isonitroso-b-ketoimine.

关键词： cobalt complex isonitroso-b-ketoimine Schiff base crystal structure

Lp integrability of trigonometric series with special varying coefficients

在线全文

学校读者我要写书评

暂无评论

Applied mathematics:A Journal of Chinese Universities 2009年第4期24卷 402-410页

作者： WEI Bao-rong department of mathematics,Hangzhou normal university,zhejiang 310036,china department of mathematics Hangzhou Normal University Zhejiang 310036 China

Very recently,Yu,Le and Zhou introduced the so called Δ*B1 and Δ*B2 conditions,which are generalizations of the monotone *** applying these two new conditions,the author essentially generalizes the classical results of Chen on the necessary and sufficient conditions of the Lp integrability of trigonometric *** fact,the present paper gives the first result on the necessary and sufficient conditions of the Lp integrability of trigonometric series,where coefficients may have diffierent signs.

关键词： Lp integrability trigonometric series special varying coefficients

On Holomorphic Automorphisms of a Class of Non-homogeneous Rigid Hypersurfaces in C^(N+1)

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Annals of mathematics,Series B 2010年第2期31卷 201-210页

作者： Qingyan WU department of mathematics,Linyi normal university,Linyi 276005,Shandong,china department of mathematics,zhejiang university,Hangzhou 310027,china department of mathematics Linyi Normal University Linyi 276005 Shandong China department of mathematics Zhejiang University Hangzhou 310027 China

The author determines the real-analytic infinitesimal CR automorphisms of a class of non-homogeneous rigid hypersurfaces in CN+1 near the origin,and the connected component containing the identity transformation of al... 详细信息

关键词： Real-analytic infinitesimal CR automorphisms Rigid hypersurfaces Holomorphic automorphisms

A Review on the Application of Deep Learning Methods in Detection and Identification of Rice Diseases and Pests

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第1期78卷 197-225页

作者： Xiaozhong Yu jinhua Zheng College of Computer Science and Technology Hengyang Normal UniversityHengyang421002China Hunan Provincial Key Laboratory of Intelligent Information Processing and Application Hengyang Normal UniversityHengyang421002China

In rice production,the prevention and management of pests and diseases have always received special *** methods require human experts,which is costly and *** to the complexity of the structure of rice diseases and pests,quickly and reliably recognizing and locating them is ***,deep learning technology has been employed to detect and identify rice diseases and *** paper introduces common publicly available datasets;summarizes the applications on rice diseases and pests from the aspects of image recognition,object detection,image segmentation,attention mechanism,and few-shot learning methods according to the network structure differences;and compares the performances of existing ***,the current issues and challenges are explored fromthe perspective of data acquisition,data processing,and application,providing possible solutions and *** study aims to review various DL models and provide improved insight into DL techniques and their cutting-edge progress in the prevention and management of rice diseases and pests.

关键词： Deep learning rice diseases and pests image recognition object detection

CODIMENSION 3 BIFURCATIONS OFHOMOCLINIC ORBITS WITH ORBITFLIPS AND INCLINATION FLIPS

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Annals of mathematics,Series B 2004年第4期25卷 555-566页

作者： SHUISHULIANG ZHUDEMING CollegeofmathematicsandPhysics ZhejiangNormalUniversityJinhua321004ZhejiangChina. departmentofmathematics EastChinaNormalUniversityShanghai200062China.

The homoclinic bifurcations in four dimensional vector fields are investigated by setting up a local coordinates near the homoclinic orbit. This homoclinic orbit is nonprincipal in the meanings that its positive semi-orbit takes orbit flip and its unstable foliation takes inclination flip. The existence, nonexistence, uniqueness and coexistence of the 1-homoclinic orbit and the 1-periodic orbit are studied. The existence of the twofold periodic orbit and three-fold periodic orbit are also obtained.

关键词： Bifurcation Homoclinic orbit Orbit flip Inclination flip Periodic orbit

Dynamical understanding of loop soliton solution for several nonlinear wave equations

在线全文

学校读者我要写书评

暂无评论

Science china mathematics 2007年第6期50卷 773-785页

作者： Ji-bin LI department of mathematics, zhejiang normal university, jinhua 32.004, china Kunming university of Science and Technology, Kunming 650093, china department of mathematics Zhejiang Normal University Jinhua 321004 China Kunming university of Science Technology Kunming 650093 China

It has been found that some nonlinear wave equations have one-loop soliton solutions. What is the dynamical behavior of the so-called one-loop soliton solution? To answer this question, the travelling wave solutions for four nonlinear wave equations are discussed. Exact explicit parametric representations of some special travelling wave solutions are given. The results of this paper show that a loop solution consists of three different breaking travelling wave solutions. It is not one real loop soliton travelling wave solution.

关键词： planar dynamical system homoclinic orbit solitary wave solution one-loop soliton solution periodic wave solution bifurcation nonlinear wave equation 34C37 34C23 74J30 58Z05

Exact traveling wave solutions and dynamical behavior for the (n+1)-dimensional multiple sine-Gordon equation

在线全文

学校读者我要写书评

暂无评论

Science china mathematics 2007年第2期50卷 153-164页

Using the methods of dynamical systems for the (n + 1)-dimensional multiple sine-Gordon equation, the existences of uncountably infinite many periodic wave solutions and breaking bounded wave solutions are obtained. For the double sine-Gordon equation, the exact explicit parametric representations of the bounded traveling solutions are given. To guarantee the existence of the above solutions, all parameter conditions are determined.

关键词： nonlinear wave bifurcation exact explicit traveling wave solution double sine-Gordon equation multiple sine-Gordon equation 35B10 35L70 35Q51