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Dissection of the genetic architecture for tassel branch number by QTL analysis in two related populations in maize 被引量:7
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作者 CHEN Zheng-jie YANG Cong +4 位作者 TANG Deng-guo ZHANG Lei ZHANG Ling QU Jing-tao LIU Jian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第7期1432-1442,共11页
Tassel branch number (TBN) is the principal component of maize tassel inflorescence architecture and is a typical quan- titative trait controlled by multiple genes. The main objective of this research was to detect ... Tassel branch number (TBN) is the principal component of maize tassel inflorescence architecture and is a typical quan- titative trait controlled by multiple genes. The main objective of this research was to detect quantitative trait loci (QTLs) for TBN. The maize inbred line SICAU1212 was used as the common parent to develop BC1S1 and recombinant inbred line (RIL) populations with inbred lines 3237 and B73, respectively. The two related populations consisted of 123 and 238 lines, respectively. Each population was grown and phenotyped for TBN in two environments. Eleven QTLs were detected in the BC1S1 population, located on chromosomes 2, 3, 5, and 7, accounted for 4.45-26.58% of the phenotypic variation. Two QTLs (qB11Jtbn2-1, qB12Ctbn2-1, qBJtbn2-1; q11JBtbn5-1, qB12Ctbn5-1, qBJtbn5-1) that accounted for more than 10% of the phenotypic variation were identified. Three QTLs located on chromosomes 2, 3 and 5, exhibited stable expres- sion in the two environments. Ten QTLs were detected in the RIL population, located on chromosomes 2, 3, 5, 8, and 10, accounted for 2.69-13.58% of the TBN variation. One QTL (qR14Dtbn2-2) explained 〉10% of the phenotypic variation. One common QTL (qB12Ctbn2-2, qR14Dtbn2-2, qRJtbn2-2) was detected between the two related populations. Three pairs of epistatic effects were identified between two loci with or without additive effects and accounted for 1.19-4.26% of the phenotypic variance. These results demonstrated that TBN variation was mainly caused by major effects, minor effects and slightly modified by epistatic effects. Thus, identification of QTL for TBN may help elucidate the genetic basis of TBN and also facilitate map-based cloning and marker-assisted selection (MAS) in maize breeding programs. 展开更多
关键词 QTL tassel branch number related populations epistatic effects
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Synthesis of Branched Chains with Actuation Redundancy for Eliminating Interior Singularities of 3T1R Parallel Mechanisms 被引量:12
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作者 LI Shihua LIU Yanmin +2 位作者 CUI Hongliu NIU Yunzhan ZHAO Yanzhi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第2期250-259,共10页
Although it is common to eliminate the singularity of parallel mechanism by adding the branched chain with actuation redundancy, there is no theory and method for the configuration synthesis of the branched chain with... Although it is common to eliminate the singularity of parallel mechanism by adding the branched chain with actuation redundancy, there is no theory and method for the configuration synthesis of the branched chain with actuation redundancy in parallel mechanism. Branched chains with actuation redundancy are synthesized for eliminating interior singularity of 3-translational and 1-rotational(3T1R) parallel mechanisms. Guided by the discriminance method of hybrid screw group according to Grassmann line geometry, all the possibilities are listed for the occurrence of interior singularities in 3T1R parallel mechanism. Based on the linear relevance of screw system and the principles of eliminating parallel mechanism singularity with actuation redundancy, different types of branched chains with actuation redundancy are synthesized systematically to indicate the layout and the number of the branched chainsinterior with actuation redundancy. A general method is proposed for the configuration synthesis of the branched chains with actuation redundancy of the redundant parallel mechanism, and it builds a solid foundation for the subsequent performance optimization of the redundant actuation parallel mechanism. 展开更多
关键词 parallel mechanism interior singularity hybrid screw group branched chain with actuation redundancy
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PpTCP18 is upregulated by lncRNA5 and controls branch number in peach (Prunus persica) through positive feedback regulation of strigolactone biosynthesis 被引量:2
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作者 Xiaobei Wang Qiuping Wang +11 位作者 Lixia Yan Yuhang Hao Xiaodong Lian Haipeng Zhang Xianbo Zheng Jun Cheng Wei Wang Langlang Zhang Xia Ye Jidong Li Bin Tan Jiancan Feng 《Horticulture Research》 SCIE CSCD 2023年第1期21-30,共10页
Branch number is an important agronomic trait in peach(Prunus persica)trees because plant architecture affects fruit yield and quality.Although breeders can select varieties with different tree architecture,the biolog... Branch number is an important agronomic trait in peach(Prunus persica)trees because plant architecture affects fruit yield and quality.Although breeders can select varieties with different tree architecture,the biological mechanisms underlying architecture remain largely unclear.In this study,a pillar peach(‘Zhaoshouhong’)and a standard peach(‘Okubo’)were compared.‘Zhaoshouhong’was found to have significantly fewer secondary branches than‘Okubo’.Treatment with the synthetic strigolactone(SL)GR24 decreased branch number.Transcriptome analysis indicated that PpTCP18(a homologous gene of Arabidopsis thaliana BRC1)expression was negatively correlated with strigolactone synthesis gene expression,indicating that PpTCP18 may play an important role in peach branching.Yeast one-hybrid,electrophoretic mobility shift,dual-luciferase assays and PpTCP18-knockdown in peach leaf buds indicated that PpTCP18 could increase expression of PpLBO1,PpMAX1,and PpMAX4.Furthermore,transgenic Arabidopsis plants overexpressing PpTCP18 clearly exhibited reduced primary rosette-leaf branches.Moreover,lncRNA sequencing and transient expression analysis revealed that lncRNA5 targeted PpTCP18,significantly increasing PpTCP18 expression.These results provide insights into the mRNA and lncRNA network in the peach SL signaling pathway and indicate that PpTCP18,a transcription factor downstream of SL signaling,is involved in positive feedback regulation of SL biosynthesis.This role of PpTCP18 may represent a novel mechanism in peach branching regulation.Our study improves current understanding of the mechanisms underlying peach branching and provides theoretical support for genetic improvement of peach tree architecture. 展开更多
关键词 branch branching number
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QTL effects and epistatic interaction for flowering time and branch number in a soybean mapping population of Japanese×Chinese cultivars 被引量:4
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作者 YANG Guang ZHAI Hong +12 位作者 WU Hong-yan ZHANG Xing-zheng LüShi-xiang WANG Ya-ying LI Yu-qiu HU Bo WANG Lu WEN Zi-xiang WANG De-chun WANG Shao-dong Kyuya Harada XIA Zheng-jun XIE Fu-ti 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第9期1900-1912,共13页
Flowering time and branching type are important agronomic traits related to the adaptability and yield of soybean. Molecular bases for major flowering time or maturity loci, E1 to E4, have been identified. However, mo... Flowering time and branching type are important agronomic traits related to the adaptability and yield of soybean. Molecular bases for major flowering time or maturity loci, E1 to E4, have been identified. However, more flowering time genes in cultivars with different genetic backgrounds are needed to be mapped and cloned for a better understanding of flowering time regulation in soybean. In this study, we developed a population of Japanese cultivar(Toyomusume)×Chinese cultivar(Suinong 10) to map novel quantitative trait locus(QTL) for flowering time and branch number. A genetic linkage map of a F_2 population was constructed using 1 306 polymorphic single nucleotide polymorphism(SNP) markers using Illumina Soy SNP8 ki Select Bead Chip containing 7 189(SNPs). Two major QTLs at E1 and E9, and two minor QTLs at a novel locus, qFT2_1 and at E3 region were mapped. Using other sets of F_2 populations and their derived progenies, the existence of a novel QTL of qFT2_1 was verified. qBR6_1, the major QTL for branch number was mapped to the proximate to the E1 gene, inferring that E1 gene or neighboring genetic factor is significantly contributing to the branch number. 展开更多
关键词 soybean quantitative trait loci SNP flowering time branch number
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ON THE BASIC REPRODUCTION NUMBER OF GENERAL BRANCHING PROCESSES 被引量:1
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作者 蓝国烈 马志明 孙苏勇 《Acta Mathematica Scientia》 SCIE CSCD 2009年第4期1081-1094,共14页
Under a very general condition (TNC condition) we show that the spectral radius of the kernel of a general branching process is a threshold parameter and hence plays a role as the basic reproduction number in usual ... Under a very general condition (TNC condition) we show that the spectral radius of the kernel of a general branching process is a threshold parameter and hence plays a role as the basic reproduction number in usual CMJ processes. We discuss also some properties of the extinction probability and the generating operator of general branching processes. As an application in epidemics, in the final section we suggest a generalization of SIR model which can describe infectious diseases transmission in an inhomogeneous population. 展开更多
关键词 general branching process extinction probability reproduction kernel spectral radius TNC condition basic reproduction number SIR model
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GENERATOR VIBRATION FAULT DIAGNOSIS METHOD BASED ON ROTOR VIBRATION AND STATOR WINDING PARALLEL BRANCHES CIRCULATING CURRENT CHARACTERISTICS 被引量:2
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作者 Wan Shuting Li Heming +1 位作者 Li Yonggang Tang Guiji 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期592-596,共5页
Rotor vibration characteristics are first analyzed, which are that the rotor vibration of fundamental frequency will increase due to rotor winding inter-turn short circuit fault, air-gap dynamic eccentricity fault, or... Rotor vibration characteristics are first analyzed, which are that the rotor vibration of fundamental frequency will increase due to rotor winding inter-turn short circuit fault, air-gap dynamic eccentricity fault, or imbalance fault, and the vibration of the second frequency will increase when the air-gap static eccentricity fault occurs. Next, the characteristics of the stator winding parallel branches circulating current are analyzed, which are that the second harmonics circulating current will increase when the rotor winding inter-turn short circuit fault occurs, and the fundamental circulating current will increase when the air-gap eccentricity fault occurs, neither being strongly affected by the imbalance fault. Considering the differences of the rotor vibration and circulating current characteristics caused by different rotor faults, a method of generator vibration fault diagnosis, based on rotor vibration and circulating current characteristics, is developed. Finally, the rotor vibration and circulating current of a type SDF-9 generator is measured in the laboratory to verify the theoretical analysis presented above. 展开更多
关键词 Generator Fault diagnosis Rotor vibration characteristic Stator winding parallel branches circulating current
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Parallelization of a Branch and Bound Algorithm on Multicore Systems 被引量:1
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作者 Chia-Shin Chung James Flynn Janche Sang 《Journal of Software Engineering and Applications》 2012年第8期621-629,共9页
The general m-machine permutation flowshop problem with the total flow-time objective is known to be NP-hard for m ≥ 2. The only practical method for finding optimal solutions has been branch-and-bound algorithms. In... The general m-machine permutation flowshop problem with the total flow-time objective is known to be NP-hard for m ≥ 2. The only practical method for finding optimal solutions has been branch-and-bound algorithms. In this paper, we present an improved sequential algorithm which is based on a strict alternation of Generation and Exploration execution modes as well as Depth-First/Best-First hybrid strategies. The experimental results show that the proposed scheme exhibits improved performance compared with the algorithm in [1]. More importantly, our method can be easily extended and implemented with lightweight threads to speed up the execution times. Good speedups can be obtained on shared-memory multicore systems. 展开更多
关键词 parallel branch and BOUND Multithreaded Programming MULTICORE System PERMUTATION FLOWSHOP Software REUSE
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QTL mapping for plant height and fruit branch number based on RIL population of upland cotton 被引量:1
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作者 LIU Ruixian XIAO Xianghui +11 位作者 GONG Juwu LI Junwen ZHANG Zhen LIU Aiying LU Quanwei SHANG Haihong SHI Yuzhen GE Qun IQBAL Muhammad Sajid CHEN Quanjia YUAN Youlu GONG Wankui 《Journal of Cotton Research》 2020年第1期54-62,共9页
Background:Plant height(PH)and fruit branch number(FBN)are important traits for improving yield and mechanical harvesting of cotton.In order to identify genes of PH and FBN in cotton germplasms to develop superior cul... Background:Plant height(PH)and fruit branch number(FBN)are important traits for improving yield and mechanical harvesting of cotton.In order to identify genes of PH and FBN in cotton germplasms to develop superior cultivars,quantitative trait loci(QTLs)for these traits were detected based on the phenotypic evaluation data in nine environments across four locations and 4 years and a previously reported genetic linkage map of an recombinant inbred line(RIL)population of upland cotton.Results:In total,53 QTLs of PH and FBN,were identified on 21 chromosomes of the cotton genome except chromosomes c02,c09-c11,and c22.For PH,27 QTLs explaining 3.81%–8.54%proportions of phenotypic variance were identified on 18 chromosomes except c02,c08-c12,c15,and c22.For FBN,26 QTLs explaining 3.23%–11.00%proportions of phenotypic variance were identified on 16 chromosomes except c02-c03,c06,c09-c11,c17,c22-c23,and c25.Eight QTLs were simultaneously identified in at least two environments.Three QTL clusters containing seven QTLs were identified on three chromosomes(c01,c18 and c21).Eleven QTLs were the same as previously reported ones,while the rest were newly identified.Conclusions:The QTLs and QTL clusters identified in the current study will be helpful to further understand the genetic mechanism of PH and FBN development of cotton and will enhance the development of excellent cultivars for mechanical managements in cotton production. 展开更多
关键词 UPLAND cotton RIL population Agronomic traits QTL Plant height FRUITING branch number
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Lower Bounds and a Nearly Fastest General Parallel Branch-and-Bound Algorithm 被引量:2
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作者 Wu, Jigang Xie, Xing +1 位作者 Wan, Yingyu Chen, Guoliang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第3期65-73,共9页
In this paper, it is supposed that the B&B algorithm finds the first optimal solution after h nodes have been expanded and m active nodes have been created in the state-space tree. Then the lower bound Ω(m+h log ... In this paper, it is supposed that the B&B algorithm finds the first optimal solution after h nodes have been expanded and m active nodes have been created in the state-space tree. Then the lower bound Ω(m+h log h) of the running time for the general sequential B&B algorithm and the lower bound Ω(m/p+h log p) for the general parallel best-first B&B algorithm in PRAM-CREW are proposed, where p is the number of processors available. Moreover, the lower bound Ω(M/p+H+(H/p) log (H/p)) is presented for the parallel algorithms on distributed memory system, where M and H represent total number of the active nodes and that of the expanded nodes processed by p processors, respectively. In addition, a nearly fastest general parallel best-first B&B algorithm is put forward. The parallel algorithm is the fastest one as p = max{hε, r}, where ε = 1/ rootlogh, and r is the largest branch number of the nodes in the state-space tree. 展开更多
关键词 branch-AND-BOUND State-space tree Active list parallel algorithm Combinatorial search.
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THE ASYMPTOTIC SOLUTION OF THE UNSTEADY PLANAR PARALLEL GAS FLOW FOR THE CASE TEAT THE ADIABATIC INDEX NUMBER γ IS BIG
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作者 Yuan Yi-wu 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第7期649-655,共7页
In ref I,under the condition that the components of velocity are only the functions of time and polar angleθ,Drornikov solved eqss.(1.1)(1.3)of the ideal gas unsteady planar parallel potential flow.It was pointed out... In ref I,under the condition that the components of velocity are only the functions of time and polar angleθ,Drornikov solved eqss.(1.1)(1.3)of the ideal gas unsteady planar parallel potential flow.It was pointed out in ref.[1]that in general cases,the evident solutions could not he obtained.Only for two especial cases,the evident solutions were obtained.In this paper,the author studies the same prohlein as that in ref.[1].In the first section we obtain the evident solution of equations(1.1)-(1.3)under the condition that the sonic velocity is restricted by some complemental conditions.In the second section,we obtain the first-order approximate solutions of the fundamental equation for the case thatγ>>1. 展开更多
关键词 adiabalie index number gas.unsteady planar parallel flow
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Influence of the Number of Reserved Fruit on Fruit-bearing Branch of Early-maturing Citrus unshiu Marc. on Fruit Growth and Development
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作者 周光萍 金方伦 +5 位作者 万敏 黎明 杨李娟 敖学熙 韩成敏 徐琼 《Agricultural Science & Technology》 CAS 2014年第2期238-242,共5页
In order to provide theoretical references for early-maturing Citrus unshiu Marc. in terms of fruit thinning, timely fertilization and harvesting, as wel as for for-mulation of of Early-maturing Citrus unshiu Marc. Cu... In order to provide theoretical references for early-maturing Citrus unshiu Marc. in terms of fruit thinning, timely fertilization and harvesting, as wel as for for-mulation of of Early-maturing Citrus unshiu Marc. Cultivation Technique Standards in Guizhou Province, the dynamic changes of fruit longitudinal diameter and trans-verse diameter of 11-year-old and 12-year-old early maturing Citrus unshiu Marc. were tested in two consecutive years and the effects of single-fruit bearing branch on fruit growth and development were compared. The results showed annual varia-tion of longitudinal and transverse diameter of the fruit in Guizhou grew faster at the beginning and then slowed down gradual y, maintaining a slow-growth period after October; the growth curve final y was flat in mature stage. General y, the growth and development stage of fruit showed four growth peaks, showing an in-creasing S-shape curve and fruit net increase also had four growth peaks with a double S-shape curve. Specifical y, longitudinal diameters growth alternated with transverse diameter growth and the former proved much stronger. In terms of ef-fects of single-fruit bearing branch on longitudinal and transverse diameter growth, the number of reserved fruits had direct effects on the growth, net increase of weight, time of growth peak, fluctuation and the number of growth peak. The growth and development, and quality of fruits in the treatments with two or three fruits re-served on single fruit-bearing branch proved better compared with the control with four left fruits. It suggested that early June and early July are the best time for fer-tilization of early-maturing Citrus unshiu Marc. in Guizhou Pprovince and would have better effect if combined with foliage spraying. The suitable harvest time is in the end of October. The preferred number of reserved fruit on single fruit-bearing branch is 2-3. In actual production, the implementation of flower and fruit thinning should also takes tree age, balance of tree vigor, strength of fruit bearing branch, alternate bearing phenomenon and other factors into consideration. 展开更多
关键词 Citrus unshiu Marc. Early-maturing cultivar FRUIT Growth and develop-ment Fruit-bearing branch The number of reserved fruit
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Optimization for Hydroforming Loading Paths of Parallel Multi-branch Tubes Based on Grey System Theory
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作者 Kai Zhang Xiao-Ting Xiao +2 位作者 Zhen Chen Hua-Dian Wen Ying Chen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第4期116-120,共5页
According to characteristic of hydroforming of parallel multi-branch tubes,multi-objective problems were transformed to single objective problem of relational grade comparison by grey system theory.Two different objec... According to characteristic of hydroforming of parallel multi-branch tubes,multi-objective problems were transformed to single objective problem of relational grade comparison by grey system theory.Two different objectives were selected,according to the principle that process parameters were optimal which of grey relational grade were maximum,the optimal loading parameters under different objective condition were obtained,and loading paths were optimized.The results indicated that parallel multi-branch tubes hydroformed under loading paths optimized by grey system theory could meet with the requirement that objective was optimal.And the optimal loading paths under different objectives were different,and the appropriate objective should be selected according to forming characteristic. 展开更多
关键词 relational grade parallel multi-branch tubes HYDROFORMING OPTIMIZATION
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THE NONLINEAR STABILITY OF PLANE PARALLEL SHEAR FLOWS WITH RESPECT TO TILTED PERTURBATIONS
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作者 许兰喜 关芳芳 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期1036-1045,共10页
The nonlinear stability of plane parallel shear flows with respect to tilted perturbations is studied by energy methods.Tilted perturbation refers to the fact that perturbations form an angleθ∈(0,π/2)with the direc... The nonlinear stability of plane parallel shear flows with respect to tilted perturbations is studied by energy methods.Tilted perturbation refers to the fact that perturbations form an angleθ∈(0,π/2)with the direction of the basic flows.By defining an energy functional,it is proven that plane parallel shear flows are unconditionally nonlinearly exponentially stable for tilted streamwise perturbation when the Reynolds number is below a certain critical value and the boundary conditions are either rigid or stress-free.In the case of stress-free boundaries,by taking advantage of the poloidal-toroidal decomposition of a solenoidal field to define energy functionals,it can be even shown that plane parallel shear flows are unconditionally nonlinearly exponentially stable for all Reynolds numbers,where the tilted perturbation can be either spanwise or streamwise. 展开更多
关键词 plane parallel shear flows energy method energy functional nonlinear stability Reynolds number
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Application of Evolution Sequential Number Theoretic Optimization in Global Optimization
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作者 刘洪谦 袁希钢 方开泰 《Transactions of Tianjin University》 EI CAS 2002年第4期221-225,共5页
Synthesis of chemical processes is of non-convex and multi-modal. Deterministic strategies often fail to find global optimum within reasonable time scales. Stochastic methodologies generally approach global solution i... Synthesis of chemical processes is of non-convex and multi-modal. Deterministic strategies often fail to find global optimum within reasonable time scales. Stochastic methodologies generally approach global solution in probability. In recogniting the state of art status in the discipline, a new approach for global optimization of processes, based on sequential number theoretic optimization (SNTO), is proposed. In this approach, subspaces and feasible points are derived from uniformly scattered points, and iterations over passing the corner of local optimum are enhanced via parallel strategy. The efficiency of the approach proposed is verified by results obtained from various case studies. 展开更多
关键词 global optimization sequential number theoretic optimization parallel optimization
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Halin图和Series-Parallel图的动态色数 被引量:1
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作者 董桂香 许振宇 《山东科技大学学报(自然科学版)》 CAS 2005年第1期101-103,共3页
图的动态着色是BruceMontgomery于2001年引入的一个新概念。本文分别证明了Halin图和非5圈的Series Parallel图的动态色数都不超过4。
关键词 HALIN图 Series—parallel 动态着色 动态色数
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Geometric Condition of 3UPS-S Parallel Mechanism in Singular Configuration 被引量:3
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作者 HAN Xianguo LIU Yanlong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第1期130-137,共8页
The existing researches on singularity of parallel mechanism are mostly limited to the property and regularity of singularity locus and there is no further research into the geometric relationship between uncontrolled... The existing researches on singularity of parallel mechanism are mostly limited to the property and regularity of singularity locus and there is no further research into the geometric relationship between uncontrolled kinematic screw and parallel mechanism in singularity. A 3UPS-S parallel mechanism is presented which fulfils 3-DOF in rotation. The regularity of nutation angle singularity is analyzed based on the Jacobian matrix, and the singularity surface of 3UPS-S parallel mechanisms is obtained. By applying the concept of reciprocal product in screw theory, the singular kinematic screw is derived when 3UPS-S parallel mechanism is in singularity. The geometric relationship between singular kinematic screw and singular configuration of 3UPS-S parallel mechanism is investigated by using programs in MATLAB. It is revealed that there are two kinds of situation. Firstly, the three limbs of 3UPS-S parallel mechanism intersect the singular kinematic screw in space simultaneously; Secondly, two limbs cross the singular kinematic screw while the third limb parallels with that screw. It is concluded that the nutation angle singularity of 3UPS-S parallel mechanism belongs to the singular linear complexes. This paper sheds light into and clarifies the geometric relationship between singular kinematic screw and singular configuration of 3UPS-S parallel mechanism. 展开更多
关键词 parallel mechanism condition number of Jacobian matrix screw theory singular linear complexes
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Detecting a Regularity in the Generation and Utilization of Primes in the Multiplicative Number Theory 被引量:2
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作者 Silviu Guiasu 《Natural Science》 2019年第6期187-196,共10页
If Goldbach’s conjecture is true, then for each prime number p there is at least one pair of primes symmetric with respect to p and whose sum is 2p. In the multiplicative number theory, covering the positive integers... If Goldbach’s conjecture is true, then for each prime number p there is at least one pair of primes symmetric with respect to p and whose sum is 2p. In the multiplicative number theory, covering the positive integers with primes, during the prime factorization, may be viewed as being the outcome of a parallel system which functions properly if and only if Euler’s formula of the product of the reciprocals of the primes is true. An exact formula for the number of primes less than or equal to an arbitrary bound is given. This formula may be implemented using Wolfram’s computer package Mathematica. 展开更多
关键词 Goldbach’s CONJECTURE Symmetric Prime Cousins Systemic Approach in number Theory parallel System Covering INTEGERS with PRIMES Euler’s FORMULA for the Product of Reciprocals of PRIMES FORMULA for the Exact number of PRIMES Less than or Equal to an Arbitrary Bound
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Run-Up Flow of a Maxwell Fluid through a Parallel Plate Channel 被引量:1
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作者 Syed Yedulla Qadri M. Veera Krishna 《American Journal of Computational Mathematics》 2013年第4期297-303,共7页
We consider the flow of an incompressible viscous Maxwell fluid between two parallel plates, initially induced by a constant pressure gradient. The pressure gradient is withdrawn and the upper plate moves with a unifo... We consider the flow of an incompressible viscous Maxwell fluid between two parallel plates, initially induced by a constant pressure gradient. The pressure gradient is withdrawn and the upper plate moves with a uniform velocity while the lower plate continues to be at rest. The arising flow is referred to as run-up flow. The unsteady governing equations are solved as initial value problem using Laplace transform technique. The expression for velocity, shear stresses on both plates and discharge are obtained. The behavior of the velocity, shear stresses and mass flux has been discussed in detail with respect to variations in different governing flow parameters and is presented through graphs. 展开更多
关键词 RUN-UP FLOW Maxwell’s Fluid LAPLACE Transforms REYNOLDS number and parallel PLATE CHANNELS
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Investigation of the Parallel Flow in the Edge Plasma of EAST
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作者 欧靖 朱思铮 《Plasma Science and Technology》 SCIE EI CAS CSCD 2007年第4期417-421,共5页
The effects of the E × B drift and ballooning-like transport on the edge plasma in EAST tokamak are investigated with a simplified fluid model. The simulation results show that the E × B drift and ballooning... The effects of the E × B drift and ballooning-like transport on the edge plasma in EAST tokamak are investigated with a simplified fluid model. The simulation results show that the E × B drift and ballooning-like transport affect the plasma behavior. When the toroidal field is reversed, at the low field side the density is much larger and temperatures (both electron and ion) are lower, and the profiles of the density and temperatures become more symmetric. With the ballooning-like transport considered, the spatial ballooning-like distribution at the low field side is not very important, but the magnitude affects the ratios of the inner/outer particle flux and energy as well as the E × B drift. At the top of the scrape-off layer, the Mach number exceeding 0.3 for the normal toroidal field and approaching 0.2 for the reversed toroidal field in the simulation are obtained when the drift and ballooning-like transport are included in the model. 展开更多
关键词 parallel flow E × B drift ballooning-like transport divertor asymmetries Mach number
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Parallel Machine Scheduling Models with Fuzzy Parameters and Precedence Constraints: A Credibility Approach
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作者 侯福均 吴祈宗 《Journal of Beijing Institute of Technology》 EI CAS 2007年第2期231-236,共6页
A method for modeling the parallel machine scheduling problems with fuzzy parameters and precedence constraints based on credibility measure is provided. For the given n jobs to be processed on m machines, it is assum... A method for modeling the parallel machine scheduling problems with fuzzy parameters and precedence constraints based on credibility measure is provided. For the given n jobs to be processed on m machines, it is assumed that the processing times and the due dates are nonnegative fuzzy numbers and all the weights are positive, crisp numbers. Based on credibility measure, three parallel machine scheduling problems and a goal-programming model are formulated. Feasible schedules are evaluated not only by their objective values but also by the credibility degree of satisfaction with their precedence constraints. The genetic algorithm is utilized to find the best solutions in a short period of time. An illustrative numerical example is also given. Simulation results show that the proposed models are effective, which can deal with the parallel machine scheduling problems with fuzzy parameters and precedence constraints based on credibility measure. 展开更多
关键词 parallel machine scheduling programming model possibility measure credibility measure fuzzy number genetic algorithm
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