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Bearing capacity and load transfer mechanism of a static drill rooted nodular pile in soft soil areas 被引量:18
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作者 Jia-jin ZHOU Kui-hua WANG +1 位作者 Xiao-nan GONG Ri-hong ZHANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2013年第10期705-719,共15页
The static drill rooted nodular pile is a new type of pile foundation consisting of precast nodular pile and the surrounding cemented soil.This composite pile has a relatively high bearing capacity and the mud polluti... The static drill rooted nodular pile is a new type of pile foundation consisting of precast nodular pile and the surrounding cemented soil.This composite pile has a relatively high bearing capacity and the mud pollution will be largely reduced during the construction process by using this type of pile.In order to investigate the bearing capacity and load transfer mechanism of this pile,a group of experiments were conducted to provide a comparison between this new pile and the bored pile.The axial force of a precast nodular pile was also measured by the strain gauges installed on the pile to analyze the distribution of the axial force of the nodular pile and the skin friction supported by the surrounding soil,then 3D models were built by using the ABAQUS finite element program to investigate the load transfer mechanism of this composite pile in detail.By combining the results of field tests and the finite element method,the outcome showed that the bearing capacity of a static drill rooted nodular pile is higher than the bored pile,and that this composite pile will form a double stress dispersion system which will not only confirm the strength of the pile,but also make the skin friction to be fully mobilized.The settlement of this composite pile is mainly controlled by the precast nodular pile;meanwhile,the nodular pile and the surrounding cemented soil can be considered as deformation compatibility during the loading process.The nodes on the nodular pile play an important role during the load transfer process,the shear strength of the interface between the cemented soil and the soil of the static drill rooted pile is larger than that of the bored pile. 展开更多
关键词 Static drill rooted nodular pile Load transfer Bearing capacity ABAQUS Double stress dispersion system Three-dimensional modeling
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建立有根、有魂、有效的中国大学通识教育 被引量:19
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作者 孙向晨 刘丽华 《复旦教育论坛》 CSSCI 北大核心 2018年第2期49-53,共5页
中国大学通识教育的发展有其必然性。通识教育的提出是新时代人才培养的内在要求,是中国大学迈向世界一流的必然要求,是国家教育战略的根本要求。中国大学通识教育应"有根",即遵循现代大学发展规律、扎根中国深厚的文化传统... 中国大学通识教育的发展有其必然性。通识教育的提出是新时代人才培养的内在要求,是中国大学迈向世界一流的必然要求,是国家教育战略的根本要求。中国大学通识教育应"有根",即遵循现代大学发展规律、扎根中国深厚的文化传统、体现中国大学优秀的育人传统;"有魂",即培养健全人格、培养具有中国魂的社会公民;"有效",即建立通识教育与专业教育相结合的有效机制、优化通识课程体系、促进通识课程与时俱进、开展"以学为中心"的教学改革。 展开更多
关键词 有根 有魂 有效 通识教育 中国大学
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Soil Urease Activity of Sundarban Mangrove Ecosystem, India 被引量:7
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作者 Subhajit Das Dipnarayan Ganguly +2 位作者 Abhishek Mukherjee Sabyasachi Chakraborty Tarun Kumar De 《Advances in Microbiology》 2017年第8期617-632,共16页
Vertical occurrence of soil urease activity along with ammonia content from three distinct regions viz. Deep forest region (No tidal action and wave attack occurs as it is furthest from river shore and it contains max... Vertical occurrence of soil urease activity along with ammonia content from three distinct regions viz. Deep forest region (No tidal action and wave attack occurs as it is furthest from river shore and it contains maximum content of organic carbon and minimum soil salinity and silicate concentration. In this zone plenty of pneumatophores, below ground root and dense vegetation are found), Rooted region (It is situated in between Deep forest region and Un-rooted region. This region contains only pneumatophores but it is devoid of long roots and vegetations. It faces wave attack and tidal action less than that of Un-rooted region) and Un-rooted region (It is closest to river shore and faces maximum wave attack and tidal action;it contains minimum organic carbon but maximum soil salinity and silicate concentration. This zone is totally devoid of any roots, pneumatophores and vegetations) of Sundarban mangrove forest ecosystem, India revealed an interesting explanation. Soil urease activity showed a decreasing pattern with increase in depth from the deep forest region of the Sundarban forest ecosystem. Soil urease activity was found to be more sensitive to soil temperature and pH rather than soil salinity. This ensured that soil urease along with the microbes present in the Sundarban forest ecosystem are more tolerant to fluctuation in salinity than that of temperature. Soil ammonia concentration was found to be directly governed by the soil urease activity [The regression equation is Ammonia in soil = -1.64 + 0.0402 Urease Activity (R-Sq = 62.9%, P < 0.001, n = 41)]. 展开更多
关键词 SOIL UREASE Activity SOIL Ammonia Deep FOREST REGION rooted REGION Un-rooted REGION and SUNDARBAN FOREST ECOSYSTEM
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Influence of the roots of mixed-planting species on the shear strength of saline loess soil 被引量:11
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作者 LIU Ya-bin HU Xia-song +2 位作者 YU Dong-mei ZHU Hai-li LI Guo-rong 《Journal of Mountain Science》 SCIE CSCD 2021年第3期806-818,共13页
In order to improve our knowledge of the mechanical effect of the roots of mixed-plantings on soil reinforcement and slope protection,the influence of roots of a mixed-planting with four herb species(Medicago sativa L... In order to improve our knowledge of the mechanical effect of the roots of mixed-plantings on soil reinforcement and slope protection,the influence of roots of a mixed-planting with four herb species(Medicago sativa L.,Elymus nutans Griseb.,Puccinellia distanx(L.),and Poa pratensis L.)and one shrub species(Caragana korshinskii Kom.)were investigated on the shear strength characteristics of saline loess soil.The root distribution characteristics were assessed via a survey when the plants grew for one year.The effects of the root biomass density,the root mass ratio(RMR)of the fine roots to the coarse roots,the moisture content,and the salt content on the shear strength index of the rooted soil were analyzed via a triaxial compression test,and the mechanism of these effects was discussed.The results indicate that the biomass density decreased linearly with increasing depth.The RMR initially decreased with depth and then increased,exhibiting in a quadratic relationship.The cohesion of the rooted soil increased linearly as the biomass density increased.The cohesion of the rooted soil initially increased with increasing RMR and salt content,and then it decreased.The turning point of the cohesion occurred when the RMR was 0.6 and the salt content was 1.18%.The internal friction angle of the rooted soil initially increased with biomass density and then decreased,and the turning point of the internal friction angle occurred when the biomass density was 0.015 g/cm3.The relationships between the internal friction angle of the rooted soil and the RMR and salt content were exponential incremental and linear subtractive relationship,respectively.Both the cohesion and the internal friction angle of the rooted soil linearly decreased with increasing moisture content. 展开更多
关键词 Xining Basin Herb species Shrub species rooted soil Saline loess soil Soil reinforcement Shear strength index
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双预应力混凝土梁桥的研究 被引量:5
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作者 符冠华 杨毅文 +1 位作者 耿小平 朱晓宁 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2001年第3期128-134,共7页
双预应力梁桥的研究就是试图通过双预应力体系降低梁高 ,从而达到节省造价 ,美化景观等目的 .本文通过大量的试验及研究分析 ,提出了双预应力梁跨中上缘获得预拉应力的新的传力锚固体系 ;通过对室内双预应力混凝土小梁的研究 ,检测了预... 双预应力梁桥的研究就是试图通过双预应力体系降低梁高 ,从而达到节省造价 ,美化景观等目的 .本文通过大量的试验及研究分析 ,提出了双预应力梁跨中上缘获得预拉应力的新的传力锚固体系 ;通过对室内双预应力混凝土小梁的研究 ,检测了预压钢筋的受力性能和预压过程中的某些影响参数 ;提出了足尺梁计算方法和截面、跨径选择方法 ;研制了新型哑铃型波纹管 ,很好地解决了预压钢筋变形、摩阻损失和管道压浆之间的矛盾 ;通过对 30m足尺梁的设计、施工、试验及观测 ,进一步完善了对施工工艺的研究 。 展开更多
关键词 双预应力 混凝土 梁桥 锚固 波纹管
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On structure of cluster algebras of geometric type Ⅰ:In view of sub-seeds and seed homomorphisms 被引量:2
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作者 Min Huang Fang Li Yichao Yang 《Science China Mathematics》 SCIE CSCD 2018年第5期831-854,共24页
Our motivation is to build a systematic method in order to investigate the structure of cluster algebras of geometric type. The method is given through the notion of mixing-type sub-seeds, the theory of seed homomorph... Our motivation is to build a systematic method in order to investigate the structure of cluster algebras of geometric type. The method is given through the notion of mixing-type sub-seeds, the theory of seed homomorphisms and the view-point of gluing of seeds. As an application, for(rooted) cluster algebras, we completely classify rooted cluster subalgebras and characterize rooted cluster quotient algebras in detail. Also,we build the relationship between the categorification of a rooted cluster algebra and that of its rooted cluster subalgebras. Note that cluster algebras of geometric type studied here are of the sign-skew-symmetric case. 展开更多
关键词 seed homomorphism mixing-type sub-seed rooted cluster morphism sub-rooted cluster algebra rooted cluster quotient algebra
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Rota-Baxter TD Algebra and Quinquedendriform Algebra 被引量:3
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作者 Shuyun Zhou Li Guo 《Algebra Colloquium》 SCIE CSCD 2017年第1期53-74,共22页
A dendriform algebra defined by Loday has two binary operations that give a two-part splitting of the associativity in the sense that their sum is associative. Sim- ilar dendriform type algebras with three-part and fo... A dendriform algebra defined by Loday has two binary operations that give a two-part splitting of the associativity in the sense that their sum is associative. Sim- ilar dendriform type algebras with three-part and four-part splitting of the associativity were later obtained. These structures can also be derived from actions of suitable linear operators, such as a Rota-Baxter operator or TD operator, on an associative algebra. Mo- tivated by finding a five-part splitting of the associativity, we consider the Rota-Baxter TD (RBTD) operator, an operator combining the Rota-Baxter operator and TD oper- ator, and coming from a recent study of Rota's problem concerning linear operators on associative algebras. Free RBTD algebras on rooted forests are constructed. We then introduce the concept of a quinquedendriform algebra and show that its defining relations are characterized by the action of an RBTD operator, similar to the cases of dendriform and tridendriform algebras. 展开更多
关键词 dendriform algebra Rota-Baxter algebra RBTD algebra free objects oper-ads rooted trees quinquedendriform algebra
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ASYMPTOTIC ENUMERATIONS FOR ROOTED PLANAR MAPS AND ROOTED OUTERPLANAR MAPS
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作者 颜基义 刘彦佩 《Chinese Science Bulletin》 SCIE EI CAS 1991年第3期188-192,共5页
All maps we deal with in this note are rooted planar ones, which, in brief, are called maps. Most of terminologies here come from Refs. [1—3]. The purpose of this note is to determine the asymptotic enumerations base... All maps we deal with in this note are rooted planar ones, which, in brief, are called maps. Most of terminologies here come from Refs. [1—3]. The purpose of this note is to determine the asymptotic enumerations based on the enumerations in [1, 2]. Bender and Richmond gave a survey of the asymptotic enumeration. New asymptotic enumerations here can be considered as a complement and improvement of the survey. 展开更多
关键词 rooted PLANAR MAP rooted outerplanar map.
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An Interview-Based Study of the Factors Influencing the Quality of Professional Training of Science Education Graduates
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作者 Xuejiao Song 《Journal of Contemporary Educational Research》 2024年第1期147-153,共7页
The proposal of the strategy of developing the country through science education has clarified China’s demand for the development of the science and education industry and the cultivation of science and education tal... The proposal of the strategy of developing the country through science education has clarified China’s demand for the development of the science and education industry and the cultivation of science and education talents,and the birth of Science Education majors is an important link in the cultivation of scientific literacy.Based on the grounded theory,we interviewed three Science Education graduates from a university and coded the interview data by using NVivo 12.0 to find eight important factors affecting their professional training and employment choices.The factors are“social factors,”“individual career choice factors,”“campus resources,”“employment advantages,”“professional self-development,”“teacher factors,”“planning for further education and employment,”and“student motivation.”This study analyzes the interaction between the influencing factors,constructs a theoretical model of the influencing factors of the quality of Science Education professional training,explores the problems of the training process of Science Education majors and employment dilemmas,and puts forward corresponding suggestions. 展开更多
关键词 Science Education Teacher training Professional development Influencing factors rooted research
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Shear resistance characteristics and influencing factors of root-soil composite on an alpine metal mine dump slope with different recovery periods
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作者 PANG Jinghao LIANG Shen +5 位作者 LIU Yabin LI Shengwei WANG Shu ZHU Haili LI Guorong HU Xiasong 《Journal of Mountain Science》 SCIE CSCD 2024年第3期835-849,共15页
Artificial vegetation restoration is the main measure for vegetation restoration and soil and water conservation in alpine mine dumps on the Qinghai-Tibet Plateau,China.However,there are few reports on the dynamic cha... Artificial vegetation restoration is the main measure for vegetation restoration and soil and water conservation in alpine mine dumps on the Qinghai-Tibet Plateau,China.However,there are few reports on the dynamic changes and the influencing factors of the soil reinforcement effect of plant species after artificial vegetation restoration under different recovery periods.We selected dump areas of the Delni Copper Mine in Qinghai Province,China to study the relationship between the shear strength and the peak displacement of the root-soil composite on the slope during the recovery period,and the influence of the root traits and soil physical properties on the shear resistance characteristics of the root-soil composite via in situ direct shear tests.The results indicate that the shear strength and peak displacement of the rooted soil initially decreased and then increased with the increase of the recovery period.The shear strength of the rooted soil and the recovery period exhibited a quadratic function relationship.There is no significant function relationship between the peak displacement and the recovery period.Significant positive correlations(P<0.05)exists between the shear strength of the root-soil composite and the root biomass density,root volume density,and root area ratio,and they show significant linear correlations(P<0.05).There are no significant correlations(P>0.05)between the shear strength of the root-soil composite and the root length density,and the root volume ratio of the coarse roots to the fine roots.A significant negative linear correlation(P<0.05)exists between the peak displacement of the rooted soil and the coarse-grain content,but no significant correlations(P>0.05)with the root traits,other soil physical property indices(the moisture content and dry density of the soil),and slope gradient.The coarse-grain content is the main factor controlling the peak displacement of the rooted soil. 展开更多
关键词 Alpine mine dump Artificial vegetation restoration period rooted soil Shear resistance characteristics root traits Soil physical properties
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Completeness of Induced Cotorsion Pairs in Representation Categories of Rooted Quivers
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作者 Zhen Xing DI Li Ping LI +1 位作者 Li LIANG Fei XU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第10期2436-2452,共17页
This paper focuses on a question raised by Holm and Jorgensen,who asked if the induced cotorsion pairs(Φ(X),Φ(X)^(⊥))and(^(⊥)Ψ(Y),Ψ(Y))in Rep(Q,A)—the category of all A-valued representations of a quiver Q—are... This paper focuses on a question raised by Holm and Jorgensen,who asked if the induced cotorsion pairs(Φ(X),Φ(X)^(⊥))and(^(⊥)Ψ(Y),Ψ(Y))in Rep(Q,A)—the category of all A-valued representations of a quiver Q—are complete whenever(X,Y)is a complete cotorsion pair in an abelian category A satisfying some mild conditions.We give an affirmative answer if the quiver Q is rooted.As an application,we show under certain mild conditions that if a subcategory L,which is not necessarily closed under direct summands,of A is special precovering(resp.,preenveloping),thenΦ(L)(resp.,Ψ(L))is special precovering(resp.,preenveloping)in Rep(Q,A). 展开更多
关键词 rooted quiver complete cotorsion pair special precovering(preenveloping)subcategory
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New Expected Value Expansions of Rooted Graphs 被引量:1
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作者 Xiao-qing TANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2015年第1期81-88,共8页
We propose a new expected value of rooted graph in this article,that is, when G is a rooted graph that each vertex may independently succeed with probability p when catastrophic thing happened, we consider the expecte... We propose a new expected value of rooted graph in this article,that is, when G is a rooted graph that each vertex may independently succeed with probability p when catastrophic thing happened, we consider the expected number of edges in the operational component of G which containing the root. And we get a very important and useful compute formula which is called deletion-contraction edge formula. By using this formula, we get the computational formulas of expected value for some special graphs. We also discuss the mean of expected value when parameter p has certain prior distribution. Finally, we propose mean-variance optimality when rooted graph has the equilibrium point which has larger mean and smaller variance. 展开更多
关键词 rooted graph expected value deletion-contraction edge formula mean-variance optimality
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Table Operation Method for Optimal Spanning Tree Problem 被引量:1
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作者 Feng Junwen(School of Economics and Management, Nanjing University of Science and Technology,210094, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第4期31-40,共10页
As far as the weight digraph is considered, based on the table instead of the weightdigraph, an optimal spanning tree method called the Table Operations Method (TOM) is proposed.And the optimality is proved and a nume... As far as the weight digraph is considered, based on the table instead of the weightdigraph, an optimal spanning tree method called the Table Operations Method (TOM) is proposed.And the optimality is proved and a numerical example is demonstrated. 展开更多
关键词 Optimal spanning tree problem DIGRAPH rooted tree Table representation
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Relative locations of operated semigroups subwords in free and Motzkin words
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作者 Shanghua ZHENG LI GUO 《Frontiers of Mathematics in China》 SCIE CSCD 2015年第5期1243-1261,共19页
Bracketed words are basic structures both in mathematics (such as Rota-Baxter algebras) and mathematical physics (such as rooted trees) where the locations of the substructures are important. In this paper, we giv... Bracketed words are basic structures both in mathematics (such as Rota-Baxter algebras) and mathematical physics (such as rooted trees) where the locations of the substructures are important. In this paper, we give the classification of the relative locations of two bracketed subwords of a bracketed word in an operated semigroup into the separated, nested, and intersecting cases. We achieve this by establishing a correspondence between relative locations of bracketed words and those of words by applying the concept of Motzkin words which are the algebraic forms of Motzkin paths. 展开更多
关键词 Bracketed word relative location operated semigroup Motzkinword Motzkin path rooted tree
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Design and Analysis of Some Third Order Explicit Almost Runge-Kutta Methods
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作者 Abdulrahman Ndanusa Khadeejah James Audu 《Applied Mathematics》 2016年第1期13-21,共9页
In this paper, we propose two new explicit Almost Runge-Kutta (ARK) methods, ARK3 (a three stage third order method, i.e., s = p = 3) and ARK34 (a four-stage third-order method, i.e., s = 4, p = 3), for the numerical ... In this paper, we propose two new explicit Almost Runge-Kutta (ARK) methods, ARK3 (a three stage third order method, i.e., s = p = 3) and ARK34 (a four-stage third-order method, i.e., s = 4, p = 3), for the numerical solution of initial value problems (IVPs). The methods are derived through the application of order and stability conditions normally associated with Runge-Kutta methods;the derived methods are further tested for consistency and stability, a necessary requirement for convergence of any numerical scheme;they are shown to satisfy the criteria for both consistency and stability;hence their convergence is guaranteed. Numerical experiments carried out further justified the efficiency of the methods. 展开更多
关键词 Almost Runge-Kutta Stability CONSISTENCY Convergence Order Conditions rooted Trees
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ON FACE PARTITION OF ROOTED OUTERPLANAR MAPS
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作者 刘彦佩 《Chinese Science Bulletin》 SCIE EI CAS 1989年第5期365-369,共5页
A summation free formula for enumerating rooted nonseparable outerplanar maps with a face partition given is herein presented. As its corollaries, some summation free formulae for the bipartite and the simple cases ar... A summation free formula for enumerating rooted nonseparable outerplanar maps with a face partition given is herein presented. As its corollaries, some summation free formulae for the bipartite and the simple cases are also derived. Moreover, the formula for planted plane trees according to a given vertex partition is demonstrated in a new way. 展开更多
关键词 rooted MAP FACE PARTITION FUNCTIONAL EQUATION enumeration.
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A Census of Petal Bundles by Genus
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作者 Yan XU Yan Pei LIU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2008年第6期937-946,共10页
This paper provides the uniform enumerative functional equation of orientable (nonori-entable) rooted petal bundles with more parameters, and deduces two recursion formulas for calculation. Accordingly, an explicit ... This paper provides the uniform enumerative functional equation of orientable (nonori-entable) rooted petal bundles with more parameters, and deduces two recursion formulas for calculation. Accordingly, an explicit expression of rooted petal bundles with up to two parameters on nonorientable surface of genus 4 is also obtained. 展开更多
关键词 rooted map enumerating function ENUMERATION petal bundles
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The Number of Rooted Circuit Boundary Maps
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作者 Yan XU Yan Pei LIU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2010年第9期1653-1666,共14页
In this article, the authors discuss two kinds of new planar maps: pan-fan maps and circuit boundary maps, and provide explicit expressions about their enumerating functions with different parameters. Meanwhile, two ... In this article, the authors discuss two kinds of new planar maps: pan-fan maps and circuit boundary maps, and provide explicit expressions about their enumerating functions with different parameters. Meanwhile, two explicit counting formulas for circuit cubic boundary maps with two parameters; the size and the valency of the root-face, are also extracted. 展开更多
关键词 rooted map enumerating function ENUMERATION circuit boundary maps
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On Global General Solutions of Complex Normal Polynomial Systems
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作者 赵晓强 秦元勋 《Science China Mathematics》 SCIE 1993年第4期394-407,共14页
In this paper, using the Strong Rooted Theorem of complex polynomial systems we prove the existence of global general solutions of a class of complex polynomial systems, discuss the qualitative structure of global gen... In this paper, using the Strong Rooted Theorem of complex polynomial systems we prove the existence of global general solutions of a class of complex polynomial systems, discuss the qualitative structure of global general solutions of normal polynomial systems, and obtain their representation theorem. Finally, we give some applications of the theorem. 展开更多
关键词 eomplex POLYNOMIAL system SINGULAR point at INFINITY STRONG rooted THEOREM GLOBAL general solution.
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NEW PROGRESS IN THEORY OF SURFACES DEFINED BY ORDINARY DIFFERENTIAL EQUATIONS~*
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作者 秦元勋 《Chinese Science Bulletin》 SCIE EI CAS 1989年第10期800-803,共4页
Here singular points of the system (E_n~*) includes both finite and infinite singular points defined by H. Poincare, but extended to complex domain.
关键词 nonlinear ordinary differential EQUATIONS strong rooted THEOREM general INTEGRAL representation THEOREM HILBERT number N(n).
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