期刊文献+
共找到6篇文章
< 1 >
每页显示 20 50 100
MAXIMUM TREES OF FINITE SEQUENCES
1
作者 WU SHIQUAN 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1995年第2期223-228,共6页
Let n, s1, s2,..., sn be non-negative integers and M(s1, s2,...,sn) ={(a1, a2,..., a.)| ai is an integer and 0≤ai ≤si for each i}. In this paper, the cardinality of maximum trees of finite sequences in M(s1, s2,...,... Let n, s1, s2,..., sn be non-negative integers and M(s1, s2,...,sn) ={(a1, a2,..., a.)| ai is an integer and 0≤ai ≤si for each i}. In this paper, the cardinality of maximum trees of finite sequences in M(s1, s2,..., sn) sn) is obtained, which generalizes some of Frankl's results on families of finite sets with prescribed cardinalities for pairwise intersections. 展开更多
关键词 tree of subsets finite sequences tree of finite sequences.
下载PDF
Determination and Analysis of Mitochondrial ND2 Gene Sequence of Anas platyrhynchos 被引量:4
2
作者 涂剑锋 司方方 +1 位作者 邢秀梅 杨福合 《Agricultural Science & Technology》 CAS 2009年第3期46-49,共4页
[Objective] The study was to analyze the phylogenesis of Anas platyrhynchos. [Method] Complete sequence of mitochondrial ND2 gene of 4 Anas platyrhynchos was determined by direct DNA sequencing based on PCR products. ... [Objective] The study was to analyze the phylogenesis of Anas platyrhynchos. [Method] Complete sequence of mitochondrial ND2 gene of 4 Anas platyrhynchos was determined by direct DNA sequencing based on PCR products. Combined with ND2 gene sequences of the Anas Linnaeus accessed in GenBank, phylogenetic tree was constructed by Neighbor-joining and maximum parsimony methods. [Result] The ND2 gene sequences of 4 Anas platyrhynchos were identical(1 041 bp in length; the nucleotide contents of A, G, T, and C were 28.91%, 13.35%, 20.75% and 36.98% respectively; A+T content approximated to that of C+G). Sequences of ND2 gene of mallard were same as spotbill duck, and had high homology with others. The phylogenetic trees indicated mallard and spotbilled duck were close in genetic relationship, both shared a haplotype; then Philippine duck, green-winged teal and northern pintail fell into branch ''A". [Conclusion] The domestic duck may be domesticated from mallard and spotbilled duck. 展开更多
关键词 Anas platyrhynchos ND2 gene sequence analysis Phylogenetic tree
下载PDF
A formulation methodology for multicomponent distillation sequences based on stochastic optimization 被引量:5
3
作者 Fei Wang Yiqing Luo Xigang Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第9期1229-1235,共7页
Based on stochastic optimization strategy, a formulation methodology is proposed for synthesizing distillation column sequences, allowing more than one middle component as the distributing components between a pair of... Based on stochastic optimization strategy, a formulation methodology is proposed for synthesizing distillation column sequences, allowing more than one middle component as the distributing components between a pair of key components in the non-sharp split. In order to represent and manipulate the distillation configuration structures, a new coding procedure is proposed in the form of one-dimensional array. Theoretically, an array can represent any kind of split(non-sharp and sharp). With the application of a binary sort tree approach, a robust flow sheet encoding and decoding procedure is developed so that the problem formulation and solution becomes tractable. In this paper,the synthesis problem is formulated as a mixed-integer nonlinear programming(MINLP) problem and an improved simulated annealing approach is adopted to solve the optimization problem. Besides, a shortcut method is applied to the evaluation of all required design parameters as well as the total function. 展开更多
关键词 Distillation sequences synthesis Non-sharp separation Simulated annealing MINLP Binary sort tree
下载PDF
The homology analysis of internal transcribed spacer sequence of ribosomal DNA in common dermatophytes
4
作者 QIANG WANG ZHAO HUI JI +6 位作者 HOU MIN LI LI JUAN ZHANG WEI LIU ZHE WAN XIAO HONG WANG DUAN LI WANG RUO YU LI 《Journal of Microbiology and Immunology》 2006年第2期110-116,共7页
In order to analyze the sequences of the internal transcribed spacer (ITS) including the 5.8 S ribosomal DNA (rDNA) of common dermatophytes, so as to obtain a rapid and accurate method to identify the species of d... In order to analyze the sequences of the internal transcribed spacer (ITS) including the 5.8 S ribosomal DNA (rDNA) of common dermatophytes, so as to obtain a rapid and accurate method to identify the species of dermatophytes and to establish the phylogenetic tree of these species to understand their relationship, 16 strains of dermatophytes were collected and preliminarily identified by morphological characteristics. General primers for fungi ITS1 and ITS4 were used to amplify the ITS rDNA of each strains with PCR. The PCR products after purification were sequenced directly and were analyzed through internet. In the results, 11 strains were identified by means of morphological features, among which 5 strains were Trichophyton, 5 strains were Microsporum and 1 was Epidermophytoa, which was consistent with the results by molecular biology. In the 5 unidentifiable strains, 1 strain was proved to be Chrysosporium by molecular biology. These strains studied could be divided into 3 different classes as indicated in the analysis of the phylogenetic tree of the sequences in ITS, which were quite different from those of morphological classification. It is evident from the above observations that the molecular method of analysis on the ITS sequences is a rapid, highly sensitive and accurate approach for the detection of dematophyte species, however, it still exhibits some limitations needing the supplementation with morphological identification. 展开更多
关键词 Dermatophyte Internal transcribed spacer sequence identification Phylogenetic tree
下载PDF
The complete genome of hydrocarbon-degrading Pseudoalteromonas sp. NJ289 and its phylogenetic relationship 被引量:2
5
作者 LIU Fangming WANG Yibin +4 位作者 QU Changfeng ZHENG Zhou MIAO Jinlai XU Hua XIAO Tian 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第2期88-93,共6页
Genus Pseudoalteromonas belongs to Family Pseudoalteromonadaceae in Gammaproteobacteria. A cold-adapted gram-negative bacterium, hydrocarbon-degrading Pseudoalteromonas sp. NJ289, was isolated from sea-ice of the Anta... Genus Pseudoalteromonas belongs to Family Pseudoalteromonadaceae in Gammaproteobacteria. A cold-adapted gram-negative bacterium, hydrocarbon-degrading Pseudoalteromonas sp. NJ289, was isolated from sea-ice of the Antarctica region, and sequenced the whole genome through the next generation sequencing platform. The assembly yielded three contigs representing two chromosomes and one plasmid with the sizes of 3.2 Mb, 636 kb and 1.8 kb, respectively. The G+C contents of genome were 40.83% and included 3 589 ORFs. Functional annotation indicated some potential roles in enzymatic activity and environmental adaptability. This study may help for understanding the population diverse, evolutionary ecology and the microbial interaction. 展开更多
关键词 Pseudoalteromonas low temperature environmental adaptability sequencing phylogenetic tree
下载PDF
A tree-shaped motion strategy for robustly executing robotic assembly tasks
6
作者 Yusuke BOTA Hajime MIZUYAMA +2 位作者 Akio NODA Tatsuya NAGATANI Ken-ichi TANAKA 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2010年第12期986-991,共6页
An assembly robot needs to be capable of executing an assembly task robustly under various uncertainties.To attain this goal,we use a task sequence tree model originally proposed for manual assembly.This model regards... An assembly robot needs to be capable of executing an assembly task robustly under various uncertainties.To attain this goal,we use a task sequence tree model originally proposed for manual assembly.This model regards an assembly task under uncertainties as a transformation of the contact state concept.The concept may contain several contact states with probabilities but these are transformed through a series of task elements into the contact state concept having only the goal state at the end.The transformed contact state concept can be classified according to the terminal condition of each task element.Thus,the whole assembly task can be designed as a tree-shaped contingent strategy called a task sequence tree.This paper proposes a systematic approach for reconfiguring a task sequence tree model for application to a robotic assembly task.In addition,by taking a 2D peg-in-hole insertion task to be performed by a robot equipped with a force sensor as an example,we confirm that the proposed approach can provide a robust motion strategy for the task and that the robot can actually execute the task robustly under bounded uncertainty according to the strategy. 展开更多
关键词 Active compliant motion Contact states Motion strategy Robotic assembly Task sequence tree
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部