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去花对菊芋数量学性状的影响 被引量:1
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作者 单丽燕 刘辉 +2 位作者 回飞 马金星 高凯 《北方园艺》 CAS 北大核心 2016年第11期68-70,共3页
以白皮菊芋为试材,通过对现蕾期菊芋去除1/4花、1/3花、1/2花、全部去除和不去花等5个处理,测定叶片、小花、分枝和块茎数量等相关指标,探讨了去花对菊芋数量学性状的影响规律,为提高菊芋块茎生物产量提供理论依据。结果表明:去花1/3、... 以白皮菊芋为试材,通过对现蕾期菊芋去除1/4花、1/3花、1/2花、全部去除和不去花等5个处理,测定叶片、小花、分枝和块茎数量等相关指标,探讨了去花对菊芋数量学性状的影响规律,为提高菊芋块茎生物产量提供理论依据。结果表明:去花1/3、1/2和全株去花提高了单株菊芋块茎数量,降低单株块茎质量,1/4去花对菊芋单株块茎数量和单个块茎质量影响不显著;去花处理降低了二级分枝和一级分枝的数量;去花处理增加了单株叶片的数量和单片叶片的质量;随着去花数量的增加,单株小花数量呈现"降-升-降"的变化规律,单个小花质量呈现"降-升"的变化趋势。 展开更多
关键词 菊芋 块茎 去花 数量学性状
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90年代中国学校体育研究现状的数量学分析——以科技期刊的文献信息学评价为依据 被引量:2
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作者 程志理 刘雪冰 +1 位作者 曾红卒 颜军 《南京体育学院学报(社会科学版)》 2002年第6期52-55,共4页
从科技期刊的文献信息学的角度,用数量学分析的方法,对最能代表未来发展走向的20世纪90年代近10年体育教育类研究论文做统计学分析。分析结果表明中国学校体育学科研究已具规模,具备了纵深发展的可能性。为使这种可能性转变为现实,结合... 从科技期刊的文献信息学的角度,用数量学分析的方法,对最能代表未来发展走向的20世纪90年代近10年体育教育类研究论文做统计学分析。分析结果表明中国学校体育学科研究已具规模,具备了纵深发展的可能性。为使这种可能性转变为现实,结合统计分析中暴露出的问题,我们提出3点对策:①进一步拓展学校体育研究论文的刊发源;②进一步扩大学校体育研究队伍,特别是高产作者群队伍的建立;③改善目前学校体育研究中选题不均衡现象,特别是要加强中、小学体育的基础理论建设。 展开更多
关键词 数量学分析 科技期刊 20世纪90年代 中国 校体育 研究状况 文献信息 体育教育
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甘肃小檗属植物的数量化学分类初试
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作者 淮虎银 马志刚 聂芳 《兰州医学院学报》 1997年第2期29-31,共3页
本文对甘肃产12种小檗属植物进行了数量化学分类探讨,分类结果与形态分类基本吻合。建议该属植物所含生物碱可以作为该属植物分类及药材鉴定的参考。
关键词 甘肃 小檗属 数量分类 中药材
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浙江紫堇属药源开发的数量化学分类研究
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作者 张渝华 徐克学 《浙江省医学科学院学报》 1990年第1期40-45,共6页
本文用数量化学分类法分析了浙江紫堇属植物的杂缘关系,提珠芽尖距紫堇Corydalis shereri var.bulbilifera的白花生元胡C.humosa值得进一步研究,并将两者与延胡素C.yanhusou作了薄层层析比较。
关键词 数量分类 种质资源 紫堇属 球芽尖距紫堇 CorydalisShereriVar
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论通货膨胀──兼评各家货币数量学说
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作者 赵志平 《北京经济瞭望》 1996年第2期17-22,共6页
论通货膨胀──兼评各家货币数量学说赵志平本文论通货膨胀将以著名经济学家的货币数量学说之嬗变为主要脉络。钱币在当今世界各国,不过是在纸上印了一个符号,小自一分一角,大至一元拾元百元,甚至百万英镑(银行本票)。是谁赋予这... 论通货膨胀──兼评各家货币数量学说赵志平本文论通货膨胀将以著名经济学家的货币数量学说之嬗变为主要脉络。钱币在当今世界各国,不过是在纸上印了一个符号,小自一分一角,大至一元拾元百元,甚至百万英镑(银行本票)。是谁赋予这个符号这样大的魔力?金属铸币已经当... 展开更多
关键词 通货膨胀 货币数量学 货币理论
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论构建有中国特色的数量税收学
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作者 李保民 《财经问题研究》 CSSCI 北大核心 1994年第4期44-48,共5页
论构建有中国特色的数量税收学李保民社会主义市场经济的建立和发展,要求税制改革不断深入发展,税收理论研究也进入了一个新时期,并取得了可喜成绩,这已被客观实践所证明。但是,由于研究力量薄弱,税务研究的内容和范围,尤其是运... 论构建有中国特色的数量税收学李保民社会主义市场经济的建立和发展,要求税制改革不断深入发展,税收理论研究也进入了一个新时期,并取得了可喜成绩,这已被客观实践所证明。但是,由于研究力量薄弱,税务研究的内容和范围,尤其是运用数学方法的探索和研究还是非常有限... 展开更多
关键词 中国 数量税收 税收
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论事理数理学的发展
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作者 谢力同 《经济数学》 2003年第1期1-7,共7页
我们谈论事理数理学的发展 ,是对数学和运筹学发展简况的回顾后作出的 ,是以人们多年来逐步发现若干事理与数理有重要联系的经验为基础来谈论的。从这种观点来看 ,事理数理学的发展 ,尚处于初始阶段。从事理与数理的联系来研究问题 ,特... 我们谈论事理数理学的发展 ,是对数学和运筹学发展简况的回顾后作出的 ,是以人们多年来逐步发现若干事理与数理有重要联系的经验为基础来谈论的。从这种观点来看 ,事理数理学的发展 ,尚处于初始阶段。从事理与数理的联系来研究问题 ,特别是研究经济发展中的理论问题 ,是大有可为的。这种研究 ,既要以经济中有关的经验、理论、统计资料为基础 ,又要有相应的计算手段 ,还要研究出一些新的数学理论和方法 ,特别是能用来处理有相互影响的数量关系的方法 ,以及用来研究包含有矛盾的事理的数学方法。本文在谈论事理数理学的一些初步研究经验之后 ,以山东大学运筹组的两项研究工作为例 ,谈谈一些实际的应用研究的经验。其中一项是在一定的简化了的情况下 。 展开更多
关键词 事理数量学 运筹 自然辩证法 系统科 经济体制改革
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Research on Yield and Quality of Hybrid Rice under Efficient Application Amount of Phosphorus and Potassium 被引量:3
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作者 熊洪 徐富贤 +4 位作者 朱永川 张林 郭晓艺 刘茂 周兴兵 《Agricultural Science & Technology》 CAS 2012年第2期343-350,共8页
[Objective] Application of P and K was not reasonable in southwest rice producing area, with no effective method for guiding application of P and K. This study aimed to conduct experiments with the same N application ... [Objective] Application of P and K was not reasonable in southwest rice producing area, with no effective method for guiding application of P and K. This study aimed to conduct experiments with the same N application and different P and K application in different ecological points, to explore a scientific and efficient management method of P and K nutrients and provide guidance for application of P and K in rice production. [Method] Hybrid rice Chuanxiang9838 was used as experimental material to study the relationship among application amount of P and K, utilization rates of P and K, rice yield and rice quality in seven ecological points of four provinces (municipalities) including Sichuan, Chongqing, Yunnan and Guizhou. The application amount per hectare of P was 37.5, 75, 112.5 and 150 kg, respectively; the application amount per hectare of K was 45, 135 and 180 kg, respectively. A total of 10 treatments were set for split-plot design with three replications. [Result] Yield of Chuanxiang9838 significantly varied in different experimental locations and under different levels of P and K, interaction of ecological point and different P and K treatments varied significantly. Yield had reached the maximum in ecological point of Yunnan Binchuan and in treatment with application of N 150 kg P 75 kg K 90 kg. Efficient utilization rates of P and K varied in each ecological point, efficient application amount of P and K in Sichuan Dongpo, Sichuan Luxian, Guizhou Xiaohe and Chongqing Yongchuan was the same, while that in Sichuan Guanghan, Sichuan Zhongjiang and Yunnan Binchuan was different. The main objective of high-yield rice production was to increase the number of effective panicles per hectare and seed setting rate. Rice quality was clustered into 2 categories by locations and 6 categories by treatments. [Conclusion] Prediction models of efficient application of P and K in rice production were established, which provided guidance for high-yield rice production and rational and efficient utilization of P and K in southwest rice area. 展开更多
关键词 Phosphorus and potassium nutrients Efficient application amount Mathematic model Mid-season hybrid rice
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FTIR Spectroscopic Study of Broad Bean Diseased Leaves 被引量:2
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作者 李志永 刘刚 +5 位作者 李伦 欧全宏 赵兴祥 张黎 周湘萍 汪禄祥 《Agricultural Science & Technology》 CAS 2012年第11期2363-2366,2408,共5页
[Objective] The aim was to indentify diseased leaves of broad bean by vibra- tional spectroscopy. [Method] In this paper, broad bean rust, fusarium rhizome rot, broad bean zonate spot, yellow leaf curl virus and norma... [Objective] The aim was to indentify diseased leaves of broad bean by vibra- tional spectroscopy. [Method] In this paper, broad bean rust, fusarium rhizome rot, broad bean zonate spot, yellow leaf curl virus and normal leaves were studied using Fourier transform infrared spectroscopy combined with chemometrics. [Result] The spectra of the samples were similar, only with minor differences in absorption inten- sity of several peaks. Second derivative analyses show that the significant difference of all samples was in the range of 1 200-700 cm2. The data in the range of 1 200- 700 cm' were selected to evaluate correlation coefficients, hierarchical cluster analy- sis (HCA) and principal component analysis (PCA). Results showed that the correla- tion coefficients are larger than 0.928 not only between the healthy leaves, but also between the same diseased leaves. The values between healthy and diseased leaves, and among diseased leaves, are all declined. HCA and PCA yielded about 73.3% and 82.2% accuracy, respectively. [Conclusion] This study demonstrated that FTIR techniques might be used to detect crop diseases. 展开更多
关键词 FTIR spectroscopy Broad bean diseases Principal component analysis Cluster analysis
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Model Recognition of Astronauts Blood Flow Change Under Sustained +Gz Acceleration
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作者 钟秋海 张高明 +1 位作者 王庆林 李宪玉 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期225-231,共7页
Aim Using animals as object of experiment to acquire various patterns of low cerebral blood pressure and reduced blood capacity in cerebral tissues of astronauts due to the load of acceleration. Methods The isotope ... Aim Using animals as object of experiment to acquire various patterns of low cerebral blood pressure and reduced blood capacity in cerebral tissues of astronauts due to the load of acceleration. Methods The isotope tracking technique was applied to mark the blood and record the dynamic curves of cerebral blood flow changes under various accelerations, and the relevant mathematical model was set up using the method of system recognition. Also the method of factor analyzing was used to select two out of the data collected by eight sensors as two factors. Results One of the two factors reflects the various patterns in the astronaut's upper body, the other for the lower body. Parameters of rise time, delay time and steady value reflect the results under different acceleration. Conclusion Whether for the upper body or the lower body, blood flow changes can be considered as a second order system model. This method provides a new technique and method of doing research on astronaut's endurance of acceleration and selecting astronauts. 展开更多
关键词 ASTRONAUTS system recognition blood volume mathematical model ACCELERATION
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MATHEMATICAL MODEL OF ~4He QUANTUM INTERFEROMETER GYROSCOPE 被引量:5
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作者 郑睿 赵伟 +2 位作者 刘建业 谢征 冯铭瑜 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第4期360-366,共7页
The mathematical model of 4He quantum interferometer gyroscope is presented. The model includes the driven equation, the current equation and the position equation. Therefore, it can sufficiently describe the gyro- sc... The mathematical model of 4He quantum interferometer gyroscope is presented. The model includes the driven equation, the current equation and the position equation. Therefore, it can sufficiently describe the gyro- scope system. The driven equation shows the thermally driven gyroscope can work for a long time but the pres- sure driven one cannot. From the current equation, the superfluid currents passing through the weak link contain the AC currents which show the rotation flux, and other currents caused by drive. As shown in the position equa- tion, the displacement of diaphragm is the only detectable parameter in the gyroscope system. The model is tested by the simulations based on experimental parameters, and can be used to research performance of the gyroscope and analyse the gyroscope error. 展开更多
关键词 4He quantum interferometer gyroscope mathematical model pressure drive thermal drive
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Transport Properties of Two Coupled Quantum Dots Under Optical Pumping
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作者 葛传楠 温俊 +1 位作者 彭菊 王伯根 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第4期598-603,共6页
Using the Keldysh-Green function,we present a theoretical study on the electron transport properties of two coupled quantum dots under optical pumping. Plateaus in the I-V curve and resonant peaks in the transmission ... Using the Keldysh-Green function,we present a theoretical study on the electron transport properties of two coupled quantum dots under optical pumping. Plateaus in the I-V curve and resonant peaks in the transmission coefficient occur and can be explained by the local electron density of states in the quantum dots. The effects of the optical pumping frequency and intensity on the transport properties of the system are also discussed. The electron dynamical localization phenomenon occurs when the optical pumping frequency is equal to the discrete hole energy level. This result can be used to realize optical control switches. 展开更多
关键词 Keldysh-Green function optical pumping quantum dot electron transport dynamical localization
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Research on Thermodynamic Properties of Polybrominated Diphenylamine by Neural Network 被引量:18
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作者 堵锡华 庄文昌 +1 位作者 史小琴 冯长君 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第1期59-64,I0001,I0002,共8页
Based on the location of bromine substituents and conjugation matrix, a new substituent po- sition index ~X not only was defined, but also molecular shape indexes Km and electronega- tivity distance vectors Mm of diph... Based on the location of bromine substituents and conjugation matrix, a new substituent po- sition index ~X not only was defined, but also molecular shape indexes Km and electronega- tivity distance vectors Mm of diphenylamine and 209 kinds of polybrominated diphenylamine (PBDPA) molecules were calculated. Then the quantitative structure-property relationships (QSPR) among the thermodynamic properties of 210 organic pollutants and 0X, K3, M29, M36 were founded by Leaps-and-Bounds regression. Using the four structural parameters as input neurons of the artificial neural network, three satisfactory QSPR models with network structures of 4:21:1, 4:24:1, and 4:24:1 respectively, were achieved by the back-propagation algorithm. The total correlation coefficients R were 0.9999, 0.9997, and 0.9995 respectively and the standard errors S were 1.036, 1.469, and 1.510 respectively. The relative mean deviation between the predicted value and the experimental value of Sθ, AfHe and △fGθ- were 0.11%, 0.34% and 0.24% respectively, which indicated that the QSPR models had good stability and superior predictive ability. The results showed that there were good nonlinear correlations between the thermodynamic properties of PBDPAs and the four structural pa- rameters. Thus, it was concluded that the ANN models established by the new substituent position index were fully applicable to predict properties of PBDPAs. 展开更多
关键词 Polybrominated diphenylamine Neural networks Molecular shape index Elec-tronegativity distance vector Substituent position index Thermodynamic properties
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Seed Shadow of Quercus liaotungensis in a Broad-leaved Forest in Dongling Mountain 被引量:20
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作者 王巍 马克平 刘灿然 《Acta Botanica Sinica》 CSCD 2000年第2期195-202,共8页
The seed shadow of oak ( Quercus liaotungensis Koidz.) was investigated in a broad_leaved deciduous forest in Dongling Mountain in 1997. The seed rain patterns under oak tree crown for three out of four oak trees fit... The seed shadow of oak ( Quercus liaotungensis Koidz.) was investigated in a broad_leaved deciduous forest in Dongling Mountain in 1997. The seed rain patterns under oak tree crown for three out of four oak trees fit quadratic distribution, with high coefficients of determination. For each of the four trees selected in this study the seed rain size estimated from the viable acorns collected from the traps deployed under the crown was low, ranging from 26 to 259. For each of the four oak trees, the average density of the seed rain under oak tree crown ranged from 0.76 to 7.26 seeds/m 2. The average seed rain density estimated from the acorns in the traps deployed randomly in the field was 1.57 seeds/m 2. After all viable acorns fell, the acorn ground density estimated from the acorns in the quadrats was 0.13 seeds/m 2, but no viable acorns were found on the ground under the tree crown of the four oak trees, although the area under the crown was over 5 folds than the area of the combined quadrats. These results indicated that a large number of acorns was removed or predated by vertebrates once the acorns fell on the ground and acorns predation was more intensive in the sites directly under the parent trees than the sites away from the parent trees; this supports the distance_dependent hypothesis. Of the total acorns of all four oak trees, the viable acorns only accounted for 18.1%, and 17.8% for acorns infected by insect larvae, 12.1% for immature acorns, 3.6% for decayed acorns, and the acorns predated by rodent directly in the crown was the highest, accounting for 48.4%. The proportion of acorns predated by animals including vertebrates and invertebrates amounts up to 78.3%, indicating that acorn predation by animals is a limiting factor affecting acorn survival before seed dispersal. The sustained time of viable acorn fall ranged from September 8 to October 3 for the four oak trees, with the peak between 16th and 26th September. The number of acorns was not significantly different among the four directions around the trunk base. 展开更多
关键词 seed shadow Quercus liaotungensis seed fate
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Living characteristics of rare and endangered species Davidia involucrata 被引量:5
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作者 吴钢 韩单恒 +3 位作者 王宏昌 罗跃初 邓红兵 赵景柱 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期39-44,J002,共7页
Dovetree (Davidia involucrate), one of the first-class protective plants in China, is a relic species of paleotropical kingdom in Tertiary period, belonging toDavidiaceae with a single genus. In recent years, the incr... Dovetree (Davidia involucrate), one of the first-class protective plants in China, is a relic species of paleotropical kingdom in Tertiary period, belonging toDavidiaceae with a single genus. In recent years, the increase of regional developing projects has led to a sharp decrease of this ancient and rare plant in naturally distributed habitats and natural population. In this paper, the biological and ecological characteristics of Dovetree were described, and the geographically distributed condition of this species in different geologic periods as well as the major reasons for dynamic changes of its population were systematically analyzed in accordance with field researches and references. The investigations conducted in different years by setting up standard sample plots showed that the population number of Dovetree increased yearly in the areas without human interference but decreased yearly in the areas with human interference. With the increase of population density and human activities decreased as the logarithmic curve:Y=?100.7ln(x)+178.09, and it has turned from a dominant population into an endangered population. Based on the former and present studies on Dovetree, some protection strategies were put foreword for protecting this ancient and rare species. Keywords Davidia involucrate - Dovetree - Geographical Distribution - Biological Characteristics - Protection Policy CLC number S718.4 Document code A Article ID 1007-662X(2004)01-0039-06 Foundation Item: This research was coordinated by the National Natural Science Foundation of China (No. 39970591)Biography: Wu Gang (1965-), Male, Professor in Key Laboratory of Systems Ecology, Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.Responsible editor: Chai Ruihai 展开更多
关键词 Davidia involucrate Dovetree Geographical Distribution Biological Characteristics Protection Policy
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浙江紫堇属植物药源开发的初步研究——Ⅱ.数量化学分类和药用种质资源探索 被引量:2
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作者 张渝华 李军 徐克学 《现代应用药学》 CSCD 1990年第5期4-8,共5页
应用数量化学分类法分析了浙江紫堇属植物的亲缘关系,提出白花土元胡和珠芽尖距紫堇值得进一步研究开发。将两者与延胡索作了薄层层析比较,结果表明白花土元胡的成分与延胡索的相似。
关键词 数量分类 白花土元明 薄层层析
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Weighted approximation of functions with singularities by Bernstein operators 被引量:8
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作者 Bao-rong WEI Yi ZHAO 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1451-1456,共6页
As an important type of polynomial approximation, approximation of functions by Bernstein operators is an important topic in approximation theory and computational theory. This paper gives global and pointwise estimat... As an important type of polynomial approximation, approximation of functions by Bernstein operators is an important topic in approximation theory and computational theory. This paper gives global and pointwise estimates for weighted approximation of functions with singularities by Bernstein operators. The main results are the Jackson's estimates of functions f∈ (Wwλ)2 andre Cw, which extends the result of (Della Vecchia et al., 2004). 展开更多
关键词 Bemstein operators Functions with singularities Weighted approximation Pointwise estimates
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Functional Integrals and Variational-Cumulant Expansion in sine-Gordon-Thirring Model 被引量:4
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作者 YAN Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期893-896,共4页
The free energy in 1D sine-Gordon- Thirring model with impurity coupling is studied by means of functional integrals and variational-cumulant expansion methods. Two variational parameters are introduced to evaluate fr... The free energy in 1D sine-Gordon- Thirring model with impurity coupling is studied by means of functional integrals and variational-cumulant expansion methods. Two variational parameters are introduced to evaluate free energy and statistical averages. It is shown that the non-perturbation method of functional integrals can be applied to strongcoupling range of fcrmion systems. 展开更多
关键词 functional integrals variational-cumulant expansion sine-Gordon Thirring model
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Lie Symmetrical Perturbation and Adiabatic Invariants of Generalized Hojman Type for Relativistic Birkhoffian Systems 被引量:4
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作者 LUO Shao-Kai GUO Yong-Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期25-30,共6页
For a relativistic Birkhoffian system, the Lie symmetrical perturbation and adiabatic invariants of generalized Bojman type are studied under general infinitesimal transformations. On the basis of the invariance of re... For a relativistic Birkhoffian system, the Lie symmetrical perturbation and adiabatic invariants of generalized Bojman type are studied under general infinitesimal transformations. On the basis of the invariance of relativistic Birkhotfian equations under general infinitesimal transformations,Lie symmetrical transformations of the system are constructed, which only depend on the Birkhoffian variables. The exact invariants in the form of generalized Hojman conserved quantities led by the Lie symmetries of relativistic Birkhoffian system without perturbations are given. Based on the definition of higher-order adiabatic invariants of a mechanical system, the perturbation of Lie symmetries for relativistic Birkhoffian system with the action of small disturbance is investigated, and a new type of adiabatic invariants of the system is obtained. In the end of the paper, an example is given to illustrate the application of the results. 展开更多
关键词 relativity BirkhofIian system Lie symmetrical perturbation exact invariant adiabatic invariant of generalized Hojman type
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Model-based optical metrology and visualization of 3-D complex objects 被引量:2
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作者 LIU Xiao-li LI A-meng +3 位作者 ZHAO Xiao-bo GAO Peng-dong TIAN Jin-dong PENG Xiang 《Optoelectronics Letters》 EI 2007年第2期115-118,共4页
This letter addresses several key issues in the process of model-based optical metrology, including three dimensional (3D) sensing, calibration, registration and fusion of range images, geometric representation, and v... This letter addresses several key issues in the process of model-based optical metrology, including three dimensional (3D) sensing, calibration, registration and fusion of range images, geometric representation, and visualization of reconstructed 3D model by taking into account the shape measurement of 3D complex structures,and some experimental results are presented. 展开更多
关键词 三维复杂目标 可视化 计量 模型 距离象 图象融合
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