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单调区间列的极限(英文)
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作者 周剑蓉 《西华大学学报(自然科学版)》 CAS 2011年第1期83-85,共3页
将单调集合列极限的形式运用于单调区间列,并结合单调数列极限的性质得出了单调区间列的极限表达式。
关键词 单调 区间列 极限
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基于Henstock积分在区间子列上的可和性研究
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作者 李伟 《菏泽学院学报》 2020年第5期1-4,共4页
在δ(x)精细分法的基础上,对非绝对型Henstock积分理论进行了研究.引进区间[a,b]上的非绝对型Henstock积分的有限可和性等性质定理,进而在Henstock引理等有关理论基础上,给出Henstock积分在区间子列上的可和性的定理,并给予详细证明.
关键词 δ(x)精细分法 HENSTOCK积分 区间 有限可和 Henstock引理
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关于闭区间套定理
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作者 朱俊恭 《遵义师范学院学报》 2002年第1期72-73,共2页
对闭区间套定理的条件作一些变动或增加,可以得到相同的结论。
关键词 区间列 区间列 半开闭区间列
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区间值序列与区间值函数列的收敛性
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作者 李改利 高丽 《延安大学学报(自然科学版)》 2021年第4期24-28,共5页
借助区间值空间上的Hausdorff度量(距离),引入了区间值序列及其收敛性概念、区间值函数列及其收敛性概念,并给出一些相关性质。
关键词 区间 区间值序 区间值函数 区间值函数 收敛性
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基于区间套理论的克隆选择算法的收敛性研究 被引量:2
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作者 刘战东 付涛 +1 位作者 戴玉刚 赵庆华 《计算机工程与科学》 CSCD 北大核心 2010年第5期57-59,共3页
克隆选择算法是基于免疫学中的克隆选择学说而产生的一种免疫优化算法。它通过克隆算子进行操作。本文首先介绍了标准的克隆选择算法;其次引入了克隆算子并对标准的克隆选择算法进行改进;然后以数列知识为基础,以抗体群的克隆选择过程... 克隆选择算法是基于免疫学中的克隆选择学说而产生的一种免疫优化算法。它通过克隆算子进行操作。本文首先介绍了标准的克隆选择算法;其次引入了克隆算子并对标准的克隆选择算法进行改进;然后以数列知识为基础,以抗体群的克隆选择过程为对象,对克隆选择算法的收敛性进行分析;最后应用区间套定理证明了算法的全局收敛性。 展开更多
关键词 克隆选择算法 克隆算子 区间套定理 区间列
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用区间套定理研究Abel收敛域的存在性与唯一性
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作者 刘北辰 《零陵学院学报》 1994年第S1期55-56,共2页
关于幂级数sum from n=0 to ∞(a_nx^n)收敛域的存在性与唯一性问题一般教科书都未给出详细的证明,给出证明的版本利用了确界定理使初学者感到困难,本文构造出一个闭区间列,利用闭区间套定理证明了收敛域的唯一性。形如sum from n=0 to ... 关于幂级数sum from n=0 to ∞(a_nx^n)收敛域的存在性与唯一性问题一般教科书都未给出详细的证明,给出证明的版本利用了确界定理使初学者感到困难,本文构造出一个闭区间列,利用闭区间套定理证明了收敛域的唯一性。形如sum from n=0 to ∞(a_nx^n)=a_0+a_1x_1+a2x^2+a_3x^3+…a_nx^n+……的函数项级数称为幂级数,为了研究其收敛域问题,我们重述一面的重要定理。 展开更多
关键词 幂级数 收敛域 存在性 区间 定理研究 绝对收敛 发散点 收敛半径 收敛区间 区间列
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三角函数多项式的实根分离 被引量:6
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作者 陈世平 刘忠 《汕头大学学报(自然科学版)》 2016年第3期25-39,共15页
本文探索非多项式型实函数的实根分离问题,实现了分离三角函数多项式实根的"完备算法",即可以找出一个互不相交的区间列,每一个区间包含函数一个实根,整个列表包含函数的全部实根,且每个区间长度可以小于任意指定精度.
关键词 三角函数多项式 实根分离 区间列 终止性
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指数函数多项式的实根分离算法 被引量:1
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作者 葛昕钰 陈世平 刘忠 《计算机应用》 CSCD 北大核心 2022年第5期1531-1537,共7页
针对超越函数多项式的实根分离问题,提出了一种指数函数多项式的区间分离算法exRoot,将非多项式型实函数的实根分离问题转化为多项式正负性判定问题进而对其求解。首先,利用泰勒替换法构造目标函数的多项式区间套;然后,将指数函数的求... 针对超越函数多项式的实根分离问题,提出了一种指数函数多项式的区间分离算法exRoot,将非多项式型实函数的实根分离问题转化为多项式正负性判定问题进而对其求解。首先,利用泰勒替换法构造目标函数的多项式区间套;然后,将指数函数的求根问题转化为多项式在区间内正负性的判定问题;最后,给出综合算法,并且试探性地应用于实特征值线性系统的可达性判定问题。所提算法在Maple中实现,输出的结果可读,且高效易行。区别于HSOLVER和数值计算方法fsolve,exRoot回避了直接讨论根的存在性问题,理论上具有终止性和完备性,且可达到任意精度,应用于最优化问题时可避免数值解带来的系统误差。 展开更多
关键词 指数函数多项式 实根分离 泰勒替换法 区间列 终止性
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Identification of Stellaria media by PCR 被引量:6
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作者 黄文哲 董婷霞 +2 位作者 戚欢阳 卢振强 詹华强 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第3期144-148,共5页
Aim To provide a rapid and reliable method for identifying the fork medicine Stellaria media (Linn. ) Cyr. (Herba Stellariae mediae) (Caryophyllaceae) from its adulterant Myosoton aquaticure (L.) Fries (Herba... Aim To provide a rapid and reliable method for identifying the fork medicine Stellaria media (Linn. ) Cyr. (Herba Stellariae mediae) (Caryophyllaceae) from its adulterant Myosoton aquaticure (L.) Fries (Herba Myosoti aquatici) (Caryophyllaceae) by polymerase chain reaction (PCR) technology. Methods A molecular genetic approach has been developed to identify S. media for the first time. 5S-rRNA spacer domain was amplified by PCR from the isolated genomic DNA, and the PCR products were then sequenced. Results The nucleotide sequences of S. media and M. aquaticum were measured to determine their identity. Furthermore, the nucleotide sequences of three Stellaria species, S. vestita, S. longifolia and S. radians, were also measured for the sake of providing the evidence of the biological phylogeny of SteUaria. Diversity between DNA sequence and restriction enzyme mapping among a variety of the species was found in their 5S-rRNA spacer domains. Conclusion The 5S-rRNA spacer domains can be used as a molecular marker for differentiating S. media from M. aquaticum and in phylogenetie studies of Stellaria. 展开更多
关键词 Stellaria media Myosoton aquaticum 5S-rRNA spacer domain DNA sequence Stellaria
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ITS1 SEQUENCES OF NUCLEAR RIBOSOMAL DNA IN WILD RICES AND CULTIVATED RICES OF CHINA AND THEIR PHYLOGENETIC IMPLICATIONS 被引量:22
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作者 周毅 邹喻苹 +2 位作者 洪德元 周骏马 陈受宜 《Acta Botanica Sinica》 CSCD 1996年第10期785-791,共7页
The first internal transcribed spacer(ITS1) of nuclear ribosomal DNA of three wild rice species and two subspecies of cultivated rice, which are distributed in China, was amplified using PCR technique and sequenced wi... The first internal transcribed spacer(ITS1) of nuclear ribosomal DNA of three wild rice species and two subspecies of cultivated rice, which are distributed in China, was amplified using PCR technique and sequenced with automated fluorescent sequencing. The sequences of ITS1 ranged from 193 bp to 218 bp in size and G/C content varied from 69.3% to 72.7%. In pairwise comparisons among the five taxa, sequence site divergence ranged from 1.5% to 10.6%. Phylogenetic analysis of ITS1 sequences using Wagner parsimony generated a single well resolved tree, which revealed that Oryza rufipogon was much more closely related to cultivated rice species than to the other two wild species. Oryza granulata was less closely related to either cultivated rice species or the other two wild species, and might be a unique and isolated taxon in the genus Oryza. The phylogenetic relationships of the three wild rice species and two cultivated rice subspecies inferred from ITS1 sequences is highly concordant with those based on the molecular evidence from isozyme, chloroplast DNA (cpDNA), mitochondrial DNA(mtDNA) and nuclear DNA (nDNA) of the genus Oryza . 展开更多
关键词 Wild rice Cultivated rice ITS1 of rDNA Sequence analysis PHYLOGENY
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有界性定理的新证法
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作者 张志国 《数学学习与研究》 2012年第15期101-101,共1页
本文利用区间套和连续函数的局部有界性给出了闭区间上连续函数的有界性定理的一种全新的证明方法.
关键词 区间列 区间 局部有界性
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sum from i=1 to n(|a_ix-b_i|)的最小值问题及其应用
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作者 陈自言 《中学数学教学》 1997年第5期29-30,共2页
定理 设函数f(x)=sum from i=1 to n(|x-c_i|)(C_i∈R,且C_i【C_i+1) (Ⅰ)当n为奇数时,不妨设c_k为这n个数中居中间的一个,则当且仅当x=c_k时,
关键词 最小值问题 绝对值 解不等式 当且仅当 区间列 不等式的解 单调增函数 方程的解 “一” 自然数
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关于基本连续及基本一致收敛性
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作者 古定桂 《嘉应大学学报》 1995年第1期36-38,共3页
本文给出函数基本连续及函数列基本一致收敛的概念,并给出一些性质。
关键词 基本连续 基本一致收敛性 区间列 数学分析 连续函数
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A Comparative Study of Methods for Delineating Sphere of Urban Influence: A Case Study on Central China 被引量:6
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作者 WANG Hao DENG Yu +1 位作者 TIAN Enze WANG Kaiyong 《Chinese Geographical Science》 SCIE CSCD 2014年第6期751-762,共12页
A number of urban and regional plans have been developed with the advancement of urbanization and regional integration, among which the delineation of sphere of urban influence and improvement of integration between t... A number of urban and regional plans have been developed with the advancement of urbanization and regional integration, among which the delineation of sphere of urban influence and improvement of integration between the city and its hinterland have be- come vital important for guiding practices. In terms of delineating sphere of urban influence, existing studies have been focused on static study by using single year data or single method, resulting in a lack of time-series longitudinal analysis or comprehensive analysis based on multiple methods This study emphasizes on comparing two methods from both the theoretical and empirical perspective. Both gravity model and improwd field model are applied to the selected study area for measurements and comparison, to explore their strengths and weaknesses. A research framework for comprehensive analysis on delineating sphere of urban influence is proposed. In the end, the differences of deli:aeating methods are illustrated and the feasibility of comprehensive analysis is discussed. Recommendations are provided for selecting appropriate methods for delineating sphere of urban influence or developing regional hierarchy system plans and urban spatial structure schemes. 展开更多
关键词 gravity model improved field model sphere of urban influence regional planning central China
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Chemical and molecular characterization of Hong Dangshen,a unique medicinal material for diarrhea in Hong Kong
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作者 张艳波 江仁望 +6 位作者 李松林 乔春峰 韩全斌 徐宏喜 黄家乐 毕培曦 邵鹏柱 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第3期202-207,共6页
Aim To investigate the plant origin and the identity of the red substance on the surface of Hong Dangshen, a unique medicinal material for diarrhea in Hong Kong. Methods The HPLC fingerprints and 5S rRNA gene spacer s... Aim To investigate the plant origin and the identity of the red substance on the surface of Hong Dangshen, a unique medicinal material for diarrhea in Hong Kong. Methods The HPLC fingerprints and 5S rRNA gene spacer sequences of Hong Dangshen were obtained and compared with those of genuine species of Radix Codonopsis. The X-ray diffraction spectrum of the red substance was analyzed and compared with that of Halloysitum fingerprints to the Codonopsis species and the highest similarity to Rubrum. Results Hong Dangshen showed very similar HPLC Codonopsis pilosula var. modesta in terms of 5S rRNA gene spacer sequences. The X-ray diffraction spectrum of the red substance was consistent with that of Halloysitum Rubrum. Conclusion The source plant of Hong Dangshen was suggested to be Codonopsis pilosula var. modesta, one of the genuine original plants of Radix Codonopsis (Dangshen) in the China Pharmacopoeia (2005 edition). The red substance on the surface of Hong Dangshen was indicated to be Halloysitum Rubrum, a traditional medicinal mineral for chronic diarrhea. Our data suggest that Hong Dangshen is derived from the roots of Codonopsis pilosula var. modesta which has been processed with Halloysitum Rubrum, and the name is suggested to be Radix Codonopsis Praeparata Halloysita Rubra. 展开更多
关键词 Radix Codonopsis Praeparata Halloysita Rubra Codonopsis pilosula var. modesta HPLC 5S rRNA gene spacer X- ray Halloysitum Rubrum LOBETYOLIN
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Molecular identification based on ITS sequences for Kappaphycus and Eucheuma cultivated in China 被引量:2
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作者 赵素芬 何培民 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第6期1287-1296,共10页
The systematic classification of the Eucheumatoideae is difficult because of their variable morphology and interpretation of reproductive structures. Kappaphycus and Eucheuma specimens cultivated on the Hainan and Fuj... The systematic classification of the Eucheumatoideae is difficult because of their variable morphology and interpretation of reproductive structures. Kappaphycus and Eucheuma specimens cultivated on the Hainan and Fujian coast of China were introduced from Vietnam, the Philippines and Indonesia. Combined with morphological characteristics, all Kappaphycus and Eucheuma cultivated strains were identified by internal transcribed spacer (ITS) sequences. The phylogenetic tree was constructed using neighbor-joining and maximum likelihood methods. The results indicate that different ITS sequence lengths occurred in the different genera and species. An obvious difference in morphology could be found in the protuberance shape between Kappaphycus and Eucheuma. The protuberance in Eucheuma was thorn-like and in Kappaphycus was wartlike or papillate. Their ITS sequence lengths differed significantly in nucleotide variation rates up to 58.55%-63.90%. All nucleotide variations occurred in the ITS1 and ITS2 regions except for five nucleotide transversions in the 5.8S rDNA region. In addition, the difference was at the branches among congeneric species. Kappaphycus sp. had branches with small buds, while K. alvarezii did not have such a feature. The nucleotide variation rates varied from 7.02% to 7.48% among species; within the same species of the clades it was <1.20%. Eucheumatoideae algae cultivated in China consisted of three clades, K. alvarezii, Kappaphycus sp., and E. denticulatum. The results indicate that ITS sequence analysis was an effective way for identification of interspecies and intraspecies phylogenetic relationships and might provide a clue for molecular identification of algal Eucheumatoideae. 展开更多
关键词 EUCHEUMA identification KAPPAPHYCUS ITS RHODOPHYTA
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Construction of Porphyra yezoensis Pure Line from Protoplasts and Its 18S rDNA Sequence Determination 被引量:3
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作者 LIUHongquan YUWengong +3 位作者 DAIJixun GONGQianhong SHIXiaochong YANGKunfeng 《Journal of Ocean University of China》 SCIE CAS 2004年第1期60-64,共5页
The wild Porphyra yezoensis collected from the Qingdao coast was used to prepare protoplasts by enzyme digestion. The pure line was constructed by cultivating the protoplasts. The 18S rDNA of the P. yezoensis pure lin... The wild Porphyra yezoensis collected from the Qingdao coast was used to prepare protoplasts by enzyme digestion. The pure line was constructed by cultivating the protoplasts. The 18S rDNA of the P. yezoensis pure line was cloned and sequenced. Sequence analysis was executed for this sequence and other 22 sequences retrieved from GenBank. A phylogenetic tree was constructed using the neighbor joining method. The results revealed a high diversity of 18S rDNA sequences in genus Porphyra and the considerable variation of 18S rDNA sequences in different strains of the same species P. yezoensis and P. tenera. Significant difference of 18S rDNA sequence was observed between P. yezoensis from Qingdao, China, and the two strains of P. yezoensis from Japan, but the three strains of P. yezoensis formed a stable clade in the phylogenetic tree. These results indicate the possibility of interspecies and intraspecies discrimination of Porphyra using the 18S rDNA sequences. 展开更多
关键词 Porphyra yezoensis 18S rDNA sequence analysis phylogenetic tree
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Analysis of Abnormal Characteristics of Regional Crustal Deformation before the Menyuan MS6.4 Earthquake by GPS Continuous Data 被引量:2
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作者 Ma Haiping Feng Jiangang +1 位作者 Guo Peng Shi Xuelu 《Earthquake Research in China》 CSCD 2017年第2期234-238,共5页
In order to study the characteristics of crustal deformation around the epicenter before the 2016 M_S6. 4 Menyuan earthquake,the GPS continuous stations of the period from 2010 to 2016 were selected according to the o... In order to study the characteristics of crustal deformation around the epicenter before the 2016 M_S6. 4 Menyuan earthquake,the GPS continuous stations of the period from 2010 to 2016 were selected according to the observation data of the tectonic environment monitoring network in Chinese Mainland. The deformation characteristics of the crust before the earthquake were discussed through inter-station baseline time series analysis and the strain time series analysis in the epicentral region. The results show that a trend turn of the baseline movement state around the epicenter region occurred after 2014,and the movement after 2014 reflects an obvious decreasing trend of compressional deformation.During this period,the stress field energy was in a certain accumulation state. Since the beginning of 2014,the EW-component linear strain and surface strain rate weakened gradually before the earthquake. It shows that there was an obvious deformation deficit at the epicentral area in the past two years,which indicates that the region accumulated a high degree of strain energy before the earthquake. Therefore,there was a significant background change in the area before the earthquake. The results of the study can provide basic research data for understanding the seismogenic process and mechanism of this earthquake. 展开更多
关键词 Menyuan Ms6. 4 earthquake GPS reference station Baseline time series Strain time series
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Sequence analysis of rDNA intergenic spacer region (IGS) as a tool for phylogenetic studies in Trichoderma spp.
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作者 Mercatelli Elisabetta Pecchia Susanna +1 位作者 Ciliegi Sandro Vannacci Giovanni 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2004年第4期460-461,共2页
Different from ribosomal genes, which contain highly conserved sequences that are detected in all organisms, the intergenic spacer of rDNA (IGS) appears to be the most rapidly-evolving spacer region. For this reason w... Different from ribosomal genes, which contain highly conserved sequences that are detected in all organisms, the intergenic spacer of rDNA (IGS) appears to be the most rapidly-evolving spacer region. For this reason we tested this region for phylogenetic studies. This report focuses on the study of IGS sequences of isolates belonging to Trichoderma section (T. viride, T. koningii, T. hamatum, T. erinaceus, T. asperellum) and Pachybasium section (T. harzianum, T. crassum, T. fasciculatum, T. oblongisporum, T. virens). Using the primer pair 28STD and CNS1, the Fast Start Taq DNA Polymerase (Roche), and a three temperature PCR protocol, products ranging from ca 1900 to 2400 bp were obtained from all tested isolates. The PCR product of 16 Trichoderma spp. isolates was cloned into a pGEM-TEeasy Vector (Promega) and sequenced. Based on a BLAST search we can conclude that the PCR product represents the whole IGS region. Multiple alignments of IGS sequences revealed two portions with different homology level. Portion A (ca 1660 bp) is the portion that contains 3’ end of 28S gene and is the more variable, while portion B (ca 830 bp), that contains the 3’ end of IGS region and the 5’ end of 18S gene, is the less variable. Comparing all sequences in region A 705 identical pairs occur out of 1704 total nucleotides (41.4%), while in region B identical pairs were 723 out of 832 total nucleotides (86.9%) . Sequence comparison of the two regions at intraspecific level (where it was possible) showed higher variability in region A (0.17%-6.8%) than in region B (0.0%-1.0%) . At interspecific level, performing all possible comparisons, the variability of region A (19.5%-52.7%) and B (0.8%- 16.9%). were significantly higher. Comparing sequences of species belonging to Trichoderma section variability of the two regions appears reduced if compared with that obtained from comparisons of species belonging to Pachybasium section. On the basis of sequence alignment, phylogenetic trees were obtained either with entire IGS, with region A, and with region B. Results of this analysis revealed that all isolates belonging to Trichoderma section grouped separately from isolates belonging to Pachybasium section. IGS region allowed us to group species according to their taxonomic position. The topology of the tree did not change substantially, varying in genetic distance only. Performing a GenBank search sequences representing the final portion of the IGS region of other fungal species were found, and we carried out a multiple alignment using also our sequences of Trichoderma spp. and Diaporthe helianthi. The phylogeny inferred from sequence alignment matched the generally accepted morphology-based classification and was identical to other molecular schemes at high taxonomic level. Data analysis was useful in establishing a broad-scale phylogeny of Ascomycota and was also useful in sorting them into statistically-supported clades. The tree showed that Trichoderma occurred in a well-supported terminal subclade of a larger clade that also contained other genera belonging to Hypocreales order. Sequence analysis of the Trichoderma spp. IGS region allowed us to design a specific PCR primer that was successfully used to amplify region A. The new reverse primer LCR2, that recognize all Trichoderma isolates, was identified in region B and confirmed for its specificity on the DNA of fungi belonging to other Ascomycota genera. Results obtained showed that IGS region seems to be an interesting and versatile tool for phylogenetic analysis, for resolving some taxonomic problems and for constructing specific primer useful for different purposes. 展开更多
关键词 IGS RDNA sequences Trichoderma spp. PHYLOGENY
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A test sequence generation method of zone controller based on timed automata 被引量:4
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作者 SONG Shuang CHEN Yue-dong 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2019年第3期266-276,共11页
In order to solve the problem of artificial generation and low efficiency of test sequences for zone controller (ZC), a model-based automatic generation method of test sequence is proposed. Firstly, the timed automata... In order to solve the problem of artificial generation and low efficiency of test sequences for zone controller (ZC), a model-based automatic generation method of test sequence is proposed. Firstly, the timed automata model is established based on function analysis of the zone controller, and the correctness of the model is verified by UPPAAL. Then by parsing the timed automata model files, state information and transition conditions can be extracted to generate test case sets. Finally, according to the serialization conditions of test cases, the test cases are serialized into test sequences by using the improved depth first search algorithm. A case, the ZC controls the train running within its jurisdiction, shows that the method is correct and can effectively improve the efficiency of test sequence generation. 展开更多
关键词 test sequence zone controller (ZC) timed automata model file parsing case serialization
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