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含参量Minty型向量似变分不等式解的上半连续性
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作者 张征 郑伯川 《成都信息工程学院学报》 2008年第1期98-100,共3页
考虑了一类Banach空间中含参量Minty型向量似变分不等式,研究了在两个参数的扰动下其解映像的上半连续的一个充分条件。
关键词 参量Minty型向量似不等式 解映像 上半连续性
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下承式钢桁结合梁桥的畸变分析
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作者 陈玉骥 罗旗帜 《中北大学学报(自然科学版)》 CAS 北大核心 2010年第4期404-408,共5页
采用对下承式钢桁结合梁桥进行连续化处理的力学模型,考虑结构在畸变荷载作用下的变形特征,给出了结构的变形能.基于能量变分原理推导了下承式钢桁结合梁在畸变荷载作用下的近似解析解.通过一个下承式钢桁结合梁桥算例分析了结构在畸变... 采用对下承式钢桁结合梁桥进行连续化处理的力学模型,考虑结构在畸变荷载作用下的变形特征,给出了结构的变形能.基于能量变分原理推导了下承式钢桁结合梁在畸变荷载作用下的近似解析解.通过一个下承式钢桁结合梁桥算例分析了结构在畸变荷载作用下的受力特性.结果表明:该桥的最大畸变位移约为双线对称活载作用下主桁最大挠度的1/3;主桁的应力水平较低,变化趋势与畸变位移相吻合;混凝土板顺桥向正应力,沿横桥向板端最大,正中为零,应力水平与双线对称活载作用下的相当. 展开更多
关键词 下承式钢桁结合梁 参量原理
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Parameter Estimations of Rayleigh Distribution 被引量:20
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作者 林金官 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第4期49-54,共6页
设随机变量X服从Rayleigh分布,其密度函数为p(x;β)=2x/βe-x^2/β,x>0,β>0为参数,对变换群G={gc;gc(x)=c^2x,c>0},本文分别在平方损失和熵损失下研究了β在G上的最优同变估计;当β有先验信息时,给出了β的Bayes估计。
关键词 Rayleigh distribution transformation group minimum risk equivariant estimations Bayesian estimations
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弹性连续系统的Noether理论
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作者 方刚 栾锡武 栾一功 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2017年第5期1278-1284,共7页
考虑弹性连续系统的Noether对称性与守恒量理论.先基于等参量变分和非等参量变分导出弹性连续系统Hamilton作用量变分的基本公式;再给出弹性连续系统Noether对称性的定义,得出其Noether对称性的判定条件——Noether等式,以及系统Noethe... 考虑弹性连续系统的Noether对称性与守恒量理论.先基于等参量变分和非等参量变分导出弹性连续系统Hamilton作用量变分的基本公式;再给出弹性连续系统Noether对称性的定义,得出其Noether对称性的判定条件——Noether等式,以及系统Noether对称性导致的Noether守恒量,并给出弹性连续系统的Noether定理;最后以弹性介质中传播的平面波为例给出应用. 展开更多
关键词 弹性连续系统 NOETHER对称性 守恒量 非等参量
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Amenability to dry processing of high ash thermal coal using a pneumatic table 被引量:2
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作者 Dey Shobhana Gangadhar B. Gopalkrishna S.J. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第6期955-961,共7页
High ash thermal coal from India was used to conduct the dry processing of fine coal using a pneumatic table to evolve a techno-economically novel technique. The fine as-received sample having 55.2g ash was subjected ... High ash thermal coal from India was used to conduct the dry processing of fine coal using a pneumatic table to evolve a techno-economically novel technique. The fine as-received sample having 55.2g ash was subjected to washability studies at variant densities from 1.4 to 2.2 to assess the amenability to separa- tion. The experiments were conducted using a central composite design for assessing the interactive effects of the variable parameters of a pneumatic table on the product yield and ash content. The performance of the pneumatic table was analyzed in terms of clean coal yield, recovery of combustibles, separation efficiency (Esp) and useful heat value of clean coal. The combustibles of clean coal obtained through a single stage operation at 35% and 38.7% ash were 40% and 63% respectively. However, the two stage processing was more effective in reducing the ash content in the clean coal. The rougher concentrate generated at higher ash level was subsequently processed in different conditions at 35% ash level, and 58g combustibles could be recovered. Hence, two stage processing increases the combustibles by 18 units and the useful heat value of clean coal increases from 1190 kcal/kg to 3750 kcal/kg. 展开更多
关键词 Dry processingAir flow rateMinimum fluidizing velocityOrganic efficiency
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Theoretical study on separation density of gravity beneficiation
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作者 JIAO Hong-guang ZHAO Xiao-nan ZHAO Yue-min 《Journal of Coal Science & Engineering(China)》 2010年第2期193-197,共5页
Separation density is one of the most concerned operating parameters in gravity beneficiation.Although equal-errors cut point or distribution density is usually used as practical separation density in gravity benefici... Separation density is one of the most concerned operating parameters in gravity beneficiation.Although equal-errors cut point or distribution density is usually used as practical separation density in gravity beneficiation, the gravity separating process complexly affected by many kinds of factors is actually carried out at a fluctuant density; namely, the practical separation density is essentially a random variable.The studied results show that the equal-errors cut point is the mathematical expectation of this random variable, and the distribution density corresponds to the highest separation efficiency in the gravity separation process.This shows that the distribution density is the best working point of the gravity separation equipment under a particular operating condition.Therefore,in order to fully develop the function of the gravity separation equipment, the distribution density should be close to the theoretical separation density unlimitedly in the range of minimum fluctuation. 展开更多
关键词 separation density gravity beneficiation equal-errors cut point distribution density random variable
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Chemical Variation in Essential Oils of Salvia Officmalis L, Ecotypes Cultivated in Albania
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作者 Elvira Bazina 《Journal of Life Sciences》 2015年第3期95-102,共8页
Salvia officinalis L. was cultivated in different geographic locations of Albania. Sage plants originated from imported seeds and wild Albanian plants. Around 30 chemical compounds were identified in the essential oil... Salvia officinalis L. was cultivated in different geographic locations of Albania. Sage plants originated from imported seeds and wild Albanian plants. Around 30 chemical compounds were identified in the essential oils of all cultivated sage plants; the latter were found to be very rich in camphen, fl-thujone, a-pinene, eucaliptol, rich to moderate in β-pinene and camphor, and less rich in a-thujone and limonene. Sharp differences in chemical composition patterns and content of individual chemical compounds were noticed between and within cultivation sites. Cultivated sage was poorer in α-thujone versus wild plants. Cultivated sage, of Albanian wild plants origin, was the richest in α-thujone (18.45%) versus imported seeds sage. β-thujone over-dominated α-thujone in all cultivated sage plants. Volatile characters of cultivated sage were indicative of the species but not of the geographic origin of plant material. Variation in essential oils composition and chemical compounds' content (biosynthetic pathways) in cultivated sage is related more to the genetic background than the environmental factors. If cultivating sage in Albania, then wild local ecotypes would be best to use as α-thujone is maintained at satisfactory levels, local natural base is preserved, unnecessary hybridization with imported seeds sage is prevented, and are more resistant and cost effective. 展开更多
关键词 SAGE Headspace-GC/MC chemical composition variation cultivation.
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F^+2心电子的能态
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作者 何铨 《上海水产学院论文集》 1983年第1期34-41,共8页
本文参照F心电子的Simpson势能函数提出F2^+心电子的势能函数可设为:U=-8Z*eo^2/[(μ+1)R]并根据这一势场的特征,设定1S、2S2、P及3d等各态含有变分参量α及β的椭园坐标试探波函数,求出各态的能量表达式,式中含有各态的Z*、R与变... 本文参照F心电子的Simpson势能函数提出F2^+心电子的势能函数可设为:U=-8Z*eo^2/[(μ+1)R]并根据这一势场的特征,设定1S、2S2、P及3d等各态含有变分参量α及β的椭园坐标试探波函数,求出各态的能量表达式,式中含有各态的Z*、R与变分参量。α及β。 展开更多
关键词 F心电子 能态 Simpson势能函数 F2^+心电子 变分参量 椭园坐标试探波函数
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Shrinkage estimation analysis of correlated binary data with a diverging number of parameters 被引量:2
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作者 XU PeiRong FU WenJiang ZHU LiXing 《Science China Mathematics》 SCIE 2013年第2期359-377,共19页
For analyzing correlated binary data with high-dimensional covariates,we,in this paper,propose a two-stage shrinkage approach.First,we construct a weighted least-squares(WLS) type function using a special weighting sc... For analyzing correlated binary data with high-dimensional covariates,we,in this paper,propose a two-stage shrinkage approach.First,we construct a weighted least-squares(WLS) type function using a special weighting scheme on the non-conservative vector field of the generalized estimating equations(GEE) model.Second,we define a penalized WLS in the spirit of the adaptive LASSO for simultaneous variable selection and parameter estimation.The proposed procedure enjoys the oracle properties in high-dimensional framework where the number of parameters grows to infinity with the number of clusters.Moreover,we prove the consistency of the sandwich formula of the covariance matrix even when the working correlation matrix is misspecified.For the selection of tuning parameter,we develop a consistent penalized quadratic form(PQF) function criterion.The performance of the proposed method is assessed through a comparison with the existing methods and through an application to a crossover trial in a pain relief study. 展开更多
关键词 correlated binary data variable selection diverging number of parameters adaptive LASSO GEE oracle properties sandwich covariance formula penalized quadratic form function
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Effects of binary interactions on the color evolution of M33
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作者 KANG XiaoYu ZHANG FengHui ZHANG Yu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第8期1505-1509,共5页
In this work, predictions of the spectral energy distribution from populations of single and binary stars are incorporated into a galactic chemical and color evolution model to explore the significance of the effects ... In this work, predictions of the spectral energy distribution from populations of single and binary stars are incorporated into a galactic chemical and color evolution model to explore the significance of the effects of the binary interactions on the color evolution of M33. We first constructed a model without binary interactions, and the model is able to reproduce most of the available observational constraints on the distribution of stellar parameters. We then run simulations with the same set of model parameters but with binary interactions considered. By comparing the results for the populations with and without binary interactions, we find that the inclusion of binary interactions makes the surface brightness greater (~0.1 mag arcsec 2) in FUV-band but smaller (~0.7 mag arcsec 2) in K-band, while it results in the FUV K color bluer (~0.8 mag). To reproduce the observations, a model that considers the binary interactions should make more gas fall onto the disk in the early time of the galaxy evolution, or increase the total stellar mass, or both. 展开更多
关键词 M33 EVOLUTION binary stars
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