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坐标变换系数张量观与杂交张量概念分析 被引量:3
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作者 殷雅俊 《力学与实践》 北大核心 2019年第1期1-9,共9页
本文致力于澄清一个十分基本的问题:坐标变换系数是否为张量?传统观念认为,坐标变换系数不是张量。为了揭示坐标变换系数的本质,本文采用"从一般到特殊"的研究策略,重塑了张量的内涵和外延,引入了杂交张量概念,进而颠覆了坐... 本文致力于澄清一个十分基本的问题:坐标变换系数是否为张量?传统观念认为,坐标变换系数不是张量。为了揭示坐标变换系数的本质,本文采用"从一般到特殊"的研究策略,重塑了张量的内涵和外延,引入了杂交张量概念,进而颠覆了坐标变换系数不是张量的传统观念,确切地讲,它就是度量张量的杂交分量。这一结果扩张了张量概念的集合,提升了张量分析学内在的统一性、对称性和不变性,减少了连续介质力学的运算量。 展开更多
关键词 坐标变换系数 杂交张量 杂交分量 度量张量的杂交分量
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Nutrient element contents of cutting seedlings of hybrid species (Liriodendron chinense x tulipifera) 被引量:2
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作者 张晓平 方炎明 丁雨龙 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期307-310,共4页
The cutting seedlings of Liriodendron chinense x tulipifera were treated with the different concentrations of auxin (treatment1: IBA of 50 gkg-1 + NAA of 300 gkg-1; treatment2: IBA of 100 gkg-1 + NAA of 300 gkg-1). Th... The cutting seedlings of Liriodendron chinense x tulipifera were treated with the different concentrations of auxin (treatment1: IBA of 50 gkg-1 + NAA of 300 gkg-1; treatment2: IBA of 100 gkg-1 + NAA of 300 gkg-1). The biomass and the nutrient element contents for different organs (root, stem, leaf) of cutting seedling of Liriodendron chinense x tulipifera were measured by the dry method, Kjeldahl method and Atomic Absorption Spectroscopy method. The result showed that the biomass of root, stem, and leaf of the cutting seedling treated with auxin was all remarkably increased. The contents of element C in root, stem and leaf had no significant difference between the control and auxin treatments, while the contents of N, P, K and Ca in stem were much lower than that in leaf and root. Variance analysis showed that for the same organ with different concentration treatment of auxin, the four nutrient elements (N, P, K, and Ca) had no significant difference in contents, while there existed significant or very significant difference in contents of the four nutrient elements in different organs with the same concentration auxin treatment. The N, P, K and Ca contents were very low in cutting seedlings; as a result, additional fertilizer should be applied to the seedlings when they were planted in the field. 展开更多
关键词 Hybrid species (Liriodendron chinense x tulipifera) Cutting Seedlings Nutrient contents
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Simulation of Flux Distribution in Central Metabolism of Saccharo-myces cerevisiae by Hybridized Genetic Algorithm
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作者 张慧敏 姚善泾 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第2期150-156,共7页
A scheme of investigating the intracellular metabolic fluxes in central metabolism of Saccharomyces cerevisiae based on isotope model and tracer experiment was developed. The metabolic model applied in this study incl... A scheme of investigating the intracellular metabolic fluxes in central metabolism of Saccharomyces cerevisiae based on isotope model and tracer experiment was developed. The metabolic model applied in this study includes the Embden-Meyerhof-Parnas pathway,the pentose phosphate pathway,the tricarboxylic acid cycle,CO2 anaplerotic reactions,ethanol and acetate formation,and pathways involved in amino acid synthesis. The approach of hybridized genetic algorithm combined with the sequential simplex technique was used to optimize a quadratic error function without the requirement of the information on the partial derivatives. The impact of some key pa-rameters on the algorithm was studied. This approach was proved to be rapid and numerically stable in the analysis of the central metabolism of S.cerevisiae. 展开更多
关键词 Saccharomyces cerevisiae metabolic flux hybridized genetic algorithm 2D NMR central metabolism
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Grey correlational and SSR analyses of cotton hybrids 被引量:1
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作者 Ma Xiongfeng Yang Daigang +7 位作者 Zhou Xiaojian Zhang Xianliang Guo Ruilin Wang Haifeng Meng Qingqin Pei Xiaoyu Zhou Kehai Zhang Wensheng 《Engineering Sciences》 EI 2013年第5期22-29,共8页
Ten upland cotton strains exhibiting 3 fiber quality traits and 8 yield traits, were grown for two years in an investigation of the correlation between grey relational analysis (GRA) and genetic identity in heterosi... Ten upland cotton strains exhibiting 3 fiber quality traits and 8 yield traits, were grown for two years in an investigation of the correlation between grey relational analysis (GRA) and genetic identity in heterosis of cot- ton hybrid. The aim was to establish the optimal approach for heterosis prediction and parent selection. Plant traits data were collected and analyzed for GRA. In addition, 72 simple sequence repeat (SSR) markers were examined and 148 polymorphisms were detected. Correlation analysis of GRA, genetic identity, Ft fiber quality and yield heterosis was conducted. Significant differences were observed between the two analytic methods, whereas compa- rable predictions were given for yield heterosis. GRA for yield exhibited slightly higher correlation than genetic identity analysis, with a correlation coefficient of 0.49. GRA and genetic analysis exhibited overlapping yet dis- tinct advantages in heterosis prediction. Therefore, these analytical methods should be integrated to achieve the op- timal heterosis prediction and parent selection. 展开更多
关键词 COTTON HETEROSIS simple sequence repeat (SSR) grey relational analysis (GRA) genetic identity CORRELATION
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Hybrid analytical resolution approach based on ambiguity function for attitude determination 被引量:8
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作者 Wen-rui JIN Chuan-run ZHAI +2 位作者 Li-duan WANG Yan-hua ZHANG Xing-qun ZHAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第7期1038-1048,共11页
When satellite navigation receivers are equipped with multiple antennas, they can deliver attitude information. In previous researches, carrier phase differencing measurement equations were built in the earth-centered... When satellite navigation receivers are equipped with multiple antennas, they can deliver attitude information. In previous researches, carrier phase differencing measurement equations were built in the earth-centered, earth-fixed (ECEF) co- ordinate, and attitude angles could be obtained through the rotation matrix between the body frame (BF) and the local level frame (LLF). Different from the conventional methods, a hybrid algorithm is presented to resolve attitude parameters utilizing the single differencing (SD) carrier phase equations established in LLF. Assuming that the cycle integer ambiguity is known, the measure- ment equations have attitude analytical resolutions by using simultaneous single difference equations for two in-view satellites. In addition, the algorithm is capable of reducing the search integer space into countable 2D discrete points and the ambiguity function method (AFM) resolves the ambiguity function within the analytical solutions space. In the case of frequency division multiple access (FDMA) for the Russian Global Orbiting Navigation Satellite System (GLONASS), a receiver clock bias estimation is employed to evaluate its carrier phase. An evaluating variable and a weighted factor are introduced to assess the integer ambiguity initialization. By static and dynamic ground experiments, the results show that the proposed approach is effective, with enough accuracy and low computation. It can satisfy attitude determination in cases of GPS alone and combined with GLONASS. 展开更多
关键词 Global positioning system (GPS) Russian Global Orbiting Navigation Satellite System (GLONASS) Analytical resolution Attitude determination Ambiguity function method (AFM)
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