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复系数多项式的根分类
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作者 张景中 梁松新 《广州师院学报(自然科学版)》 1998年第11期1-13,共13页
通过建立多项式的完全判别系统,彻底解决了复系数多项式根的完全分类问题;而且,把所得算法用Maple编成一个通用程序,使多项式的完全判别系统及其完全根分类由计算机自动生成,绝不需要人工的干预。
关键词 判别式序列 符号修订表 根分类 完全判别系统 复系数多项式
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樱桃萝卜劣质根分类及形成原因分析
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作者 解晓康 《现代农村科技》 2012年第9期15-15,共1页
樱桃萝卜的肉质根小巧玲珑,色彩鲜艳,肉质细嫩,营养丰富,深受消费者的喜爱;而且,其生长速度快,生长周期短,采用设施栽培,每年可种植10茬左右,经济效益十分可观,是蔬菜种植户种植较多的蔬菜品种之一。
关键词 樱桃萝卜 根分类 原因 劣质 蔬菜品种 种植户 色彩鲜艳 营养丰富
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下颌前牙牙根及根管变异的研究现况 被引量:7
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作者 黄超 陈克南 +3 位作者 宋倩 李思逸 张蓉 余擎 《牙体牙髓牙周病学杂志》 CAS 北大核心 2014年第11期673-676,共4页
根管治疗是目前治疗牙髓炎和根尖周病的常用方法,但是复杂的变异根管系统常常会影响根管治疗的效果,甚至导致失败。因此,强调根管形态的多样性,熟悉根管的解剖形态,具有重要的临床指导意义。本文通过回顾1984~2013年国内外对下颌前牙... 根管治疗是目前治疗牙髓炎和根尖周病的常用方法,但是复杂的变异根管系统常常会影响根管治疗的效果,甚至导致失败。因此,强调根管形态的多样性,熟悉根管的解剖形态,具有重要的临床指导意义。本文通过回顾1984~2013年国内外对下颌前牙的牙根及根管的相关报道研究,就下颌前牙,尤其是下颌尖牙的牙根及根管变异作一综述,以期为临床工作提供参考。 展开更多
关键词 恒牙 下颌前牙 管解剖形态 分类
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西甜瓜根际镰孢霉的研究
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作者 蒋萍 赵震宇 +1 位作者 王叶筠 袁自清 《新疆农业大学学报》 CAS 1995年第1期64-67,共4页
对西甜瓜整个生长发育期及采后根际镰孢霉的研究表明,西瓜根际镰孢霉种类有5种2变种:尖孢镰孢霉、尖孢镰孢霉芬芳变种、茄病镰孢霉、串珠镰孢霉、串珠镰孢霉胶孢变种、半裸镰孢霉、硫色镰孢霉;甜瓜根际镰孢霉、种类有4种1变种:... 对西甜瓜整个生长发育期及采后根际镰孢霉的研究表明,西瓜根际镰孢霉种类有5种2变种:尖孢镰孢霉、尖孢镰孢霉芬芳变种、茄病镰孢霉、串珠镰孢霉、串珠镰孢霉胶孢变种、半裸镰孢霉、硫色镰孢霉;甜瓜根际镰孢霉、种类有4种1变种:尖孢镰孢霉、尖孢镰孢霉芬芳变种、茄病镰孢霉、潮湿镰孢霉、半裸镰孢霉.其中,茄病镰孢霉分离出现频率最高,发生于西甜瓜生长各个时期及采后,尤其生长前期及后期所占比例较大,而在5叶至开花前,开花一座瓜期比例最小.尖抱镰孢霉的发生仅次于茄病镰孢霉,开花一座瓜期分离比例最大.镰孢霉的其它种分离频率都较低,只出现在西甜瓜生长发育的某个或某几个时期. 展开更多
关键词 西甜瓜 镰孢霉中图分类号S436.42西甜瓜病引起的幼苗摔倒 腐及植株枯萎发生于世界范围内
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Resistance Evaluation of Capsicum spp. Germplasm to Meloidogyne incognita 被引量:3
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作者 刘子记 杜公福 +2 位作者 朱婕 申龙斌 曹振木 《Agricultural Science & Technology》 CAS 2016年第7期1723-1728,共6页
[Objective] This study aimed to screen out hot pepper germplasms highly resistant to Meloidogyne incognita, thereby providing resistant resources for hot pep- per breeding. [Method] Comprehensive analysis combining cl... [Objective] This study aimed to screen out hot pepper germplasms highly resistant to Meloidogyne incognita, thereby providing resistant resources for hot pep- per breeding. [Method] Comprehensive analysis combining cluster analysis and sub- ordinate function was conducted through determining related resistance indexes of 67 hot pepper germplasms 50 days after inoculated with M. incognita. [Result] The effects of M. incognita on related resistance indexes were significantly different am- ong the hot pepper germplasms. Egg index and gall index had abundant genetic variation with variation coefficients of 143.16% and 118.95%, respectively. Based on the gall indexes, cluster analysis of hot pepper germplasms was performed. The 67 hot pepper germplasms were divided into 4 groups (resistant, moderately resistant, susceptible and high susceptible). The resistance intensity of the hot pepper germplasms were ranked according to the sum of subordinate function values of various resistance indexes. The total function values of Rela 2 and L506M were the largest (2.00), indicating that these two germplasms were immune to M. incognita. The total function values of L287-2, L522-1M, L504M, L515-2, 13SM100-1, L512M, L292-1, L319, L316, L317, 13SM87-1 and Rela 5 were larger than 1.95, indicating that these germplasms were highly resistant to M. incognita. [Conclusion] This study could provide certain resistant resources for resistance breeding of hot pepper to M. incognita. 展开更多
关键词 Capsicum spp. Gerrnplasm Meloidogyne incognita Resistance index Cluster analysis Subordinate function analysis
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Study on Rhizome Crops by Fourier Transform Infrared Spectroscopy Combined with Wavelet Analysis
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作者 任静 刘刚 +4 位作者 赵兴祥 赵帅群 欧全宏 徐娟 胡见飞 《Agricultural Science & Technology》 CAS 2015年第7期1522-1526,共5页
In order to distinguish 8 kinds of rhizome crops, the 40 samples were studied by Fourier transform infrared spectroscopy (FTIR) combined with wavelet transform (WT), principal component analysis (PCA) and hieram... In order to distinguish 8 kinds of rhizome crops, the 40 samples were studied by Fourier transform infrared spectroscopy (FTIR) combined with wavelet transform (WT), principal component analysis (PCA) and hieramhical cluster analysis (HCA). The results showed that the infrared spectra were similar on the whole, but there were differences in peak position, peak shape and peak absorption intensity in the range of 1 800-700 cm-1. The infrared spectra in the range of 1 800-700 cm-1 were selected to perform continuous wavelet transform (CWT) and discrete wavelet transform (DWT). The 15th-Ievel decomposition coefficients of CWT and the 5=-level detail coefficients of DWT were classified by PCA and HCA. The cumulative contri- bution rates of the first three principal components of CWT and DWT were 93.12% and 89.78%, respectively. The accurate recognition rates of PCA and HCA were all 100%. It is proved that FTIR combined with WT can be used to distinguish different kinds of rhizome crops. 展开更多
关键词 FTIR Rhizome crop Wavelet transform Principal component analysis Hierarchical cluster analysis
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Phytochemical Constituents and Allelopathic Effects of Some Medicinal Plants Extract on the Soil Algal Diversity
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作者 Mustafa Ahmed Fawzy AwatiefFahmey Hifney Ahmed Abdel-Salam Issa Gamal Gareib 《Journal of Agricultural Science and Technology(A)》 2013年第12期1000-1009,共10页
Phytochemical constituents of the shoots and roots extract of chosen eight medicinal plants (Plantago major, Verbesina encelioides, Glinus lotoides, Helotropium supinum, Mentha microphylla, Euphorbia hirta, Juncus su... Phytochemical constituents of the shoots and roots extract of chosen eight medicinal plants (Plantago major, Verbesina encelioides, Glinus lotoides, Helotropium supinum, Mentha microphylla, Euphorbia hirta, Juncus subulatus and Convolvulus arvensis) were estimated using standard qualitative analysis. The extract contained alkaloids, glycosides, saponins, phenols, tannins, f[avonoids and terpenoids in some medicinal plants while others contain some only of these phytochemical components. Allelopathic effect of the various concentrations of the extracts on the soil algal diversity was also investigated. Wollea saccata was the only algal species disappeared from all applied investigated plant extracts. Phormidium richardsii, Monoraphidium braunii, Eunotia verneris and Nitzschia bilobata were the highly sensitive algal species to all applied shoot and root extract from all tested plants, they disappeared from most of the studied plants. On the other hand, Phormidium animale and Chlorella neustonice were highly tolerant algal species to all applied extracts. Counts of Cyanophyceae, Chlorophyceae and Bacillariophyceae were decreased by addition of some investigated medicinal plants extracts such as Juncus subulatus, Convolvulus arvensis and Euphorbia hirta. So the authors can use these plants extracts in biocontrol of the nuisance of algal bloom or any other microorganisms. Also, these plants may be useful to recover eutrophic water which needs further investigation. 展开更多
关键词 ALLELOPATHY ALLELOCHEMICALS Plantago major Verbesina encelioides Glinus lotoides Phormidium richardsii Monoraphidium braunii.
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浅谈导数在解决函数问题中对参数的几种分类讨论 被引量:1
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作者 张跃龙 《高考》 2021年第1期163-164,共2页
纵观历年高考对导数的应用,都会以"一大一小"的格局出现,"一小"即以选择题或以填空题的形式考查导数的几何意义和导数在研究函数问题中的直接应用。"一大"即以压轴题的形式考查导数、不等式、方程等方面... 纵观历年高考对导数的应用,都会以"一大一小"的格局出现,"一小"即以选择题或以填空题的形式考查导数的几何意义和导数在研究函数问题中的直接应用。"一大"即以压轴题的形式考查导数、不等式、方程等方面的综合应用,难度较大。作为高考必考热点内容,有一定程度的综合性,方法能力要求较高,承载着高考对数学学科考查的数学素养包括数学方法、数学思想、数学能力、思维逻辑以及解决实际问题的能力,是整个高中数学的核心板块、学习线索、其它知识的载体——函数的集中,全面考查,份量很高,是每年高考复习的重点难点。特别是在解决问题的过程中往往要涉及到对参数进行分类讨论这一难点,综合师生在实际解决试题过程中缺乏对参量进行分类讨论的思维意识,笔者就这一难点问题以高考试题为素材对参数进行分类讨论的理由,分类的依据,进行探讨,进而得出对参数进行分类讨论的几种模式。 展开更多
关键词 含参数函数的单调性 基础前提 的数量分类 的大小分类 极点和定义域区间相对位置的分类
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复系数多项式完全判别系统及其自动生成 被引量:1
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作者 张景中 梁松新 《中国科学(E辑)》 CSCD 1999年第1期61-75,共15页
通过建立多项式的完全判别系统 ,彻底解决了复系数多项式根的完全分类问题 ;而且 ,把所得算法用Maple编成一个通用程序 ,使多项式的完全判别系统及其完全根分类由计算机自动生成 ,绝不需要人工的干预 ;另外 ,还利用自动生成多项式根分... 通过建立多项式的完全判别系统 ,彻底解决了复系数多项式根的完全分类问题 ;而且 ,把所得算法用Maple编成一个通用程序 ,使多项式的完全判别系统及其完全根分类由计算机自动生成 ,绝不需要人工的干预 ;另外 ,还利用自动生成多项式根分类的结果 ,给出判定一元、二元多项式正定 (正半定 )性的具体方法及其自动实现 . 展开更多
关键词 根分类 完全判别系统 正定 复系数多项式 多项式
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基于无线传感器网络定位技术的图书馆智能管理创新 被引量:3
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作者 罗桦 陈勇 +2 位作者 张清 赵滟 黄猛 《大学图书情报学刊》 2016年第2期50-52,57,共4页
"互联网+"时代,信息技术的发展对图书馆的智能化管理工作提出了更高的要求。文章概述了无线传感器网络与定位技术,重点讨论了如何将WSN定位技术运用到图书智能管理,通过定位技术与大数据、云计算等信息技术的结合,推动图书馆... "互联网+"时代,信息技术的发展对图书馆的智能化管理工作提出了更高的要求。文章概述了无线传感器网络与定位技术,重点讨论了如何将WSN定位技术运用到图书智能管理,通过定位技术与大数据、云计算等信息技术的结合,推动图书馆智能系统建设和智能化发展。 展开更多
关键词 图书馆 智能管理 无线传感器网络 定位技术 互联网+
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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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