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TVP3 3rd Generation of Heat-setting Solutions
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《China Textile》 2008年第7期58-59,共2页
The heat-setting of carpet yarns is a necessary process if you want to obtain a high quality woven or tufted carpet. Different setting processes exist, each with its respective advantages and drawbacks (hot air, overh... The heat-setting of carpet yarns is a necessary process if you want to obtain a high quality woven or tufted carpet. Different setting processes exist, each with its respective advantages and drawbacks (hot air, overheated steam, saturated steam under pressure). 展开更多
关键词 TVP3 3rd Generation of Heat-setting solutions HEAT high LINE
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Third-Order Adjoint Sensitivity Analysis of an OECD/NEA Reactor Physics Benchmark: I. Mathematical Framework 被引量:2
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作者 Dan Gabriel Cacuci Ruixian Fang 《American Journal of Computational Mathematics》 2020年第4期503-528,共26页
This work extends to third-order previously published work on developing the adjoint sensitivity and uncertainty analysis of the numerical model of a <u>p</u>oly<u>e</u>thylene-<u>r</u... This work extends to third-order previously published work on developing the adjoint sensitivity and uncertainty analysis of the numerical model of a <u>p</u>oly<u>e</u>thylene-<u>r</u>eflected <u>p</u>lutonium (acronym: PERP) OECD/NEA reactor physics benchmark. The PERP benchmark comprises 21,976 imprecisely known (uncertain) model parameters. Previous works have used the adjoint sensitivity analysis methodology to compute exactly and efficiently all of the 21,976 first-order and (21,976)<sup>2</sup> second-order sensitivities of the PERP benchmark’s leakage response to all of the benchmark’s uncertain parameters, showing that the largest and most consequential 1<sup>st</sup>- and 2<sup>nd</sup>-order response sensitivities are with respect to the total microscopic cross sections. These results have motivated extending the previous adjoint-based derivations to third-order, leading to the derivation, in this work, of the exact mathematical expressions of the (180)<sup>3</sup> third-order sensitivities of the PERP leakage response with respect to these total microscopic cross sections. The formulas derived in this work are valid not only for the PERP benchmark but can also be used for computing the 3<sup>rd</sup>-order sensitivities of the leakage response of any nuclear system involving fissionable material and internal or external neutron sources. Subsequent works will use the adjoint-based mathematical expressions obtained in this work to compute exactly and efficiently the numerical values of these (180)<sup>3</sup> third-order sensitivities (which turned out to be very large and consequential) and use them for a third-order uncertainty analysis of the PERP benchmark’s leakage response. 展开更多
关键词 Polyethylene-Reflected Plutonium Sphere 1st-order 2nd-order and 3rd-order Sensitivities 3rd-order Adjoint Sensitivity Analysis Microscopic Total Cross Sections Expected Value Variance and Skewness of Response Distribution
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Third Order Adjoint Sensitivity and Uncertainty Analysis of an OECD/NEA Reactor Physics Benchmark: II. Computed Sensitivities 被引量:3
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作者 Ruixian Fang Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2020年第4期529-558,共30页
This work presents the results of the exact computation of (180)<sup>3</sup> = 5,832,000 third-order mixed sensitivities of the leakage response of a polyethylene-reflected plutonium (PERP) experimental be... This work presents the results of the exact computation of (180)<sup>3</sup> = 5,832,000 third-order mixed sensitivities of the leakage response of a polyethylene-reflected plutonium (PERP) experimental benchmark with respect to the benchmark’s 180 microscopic total cross sections. This computation was made possible by applying the Third-Order Adjoint Sensitivity Analysis Methodology developed by Cacuci. The numerical results obtained in this work revealed that many of the 3<sup>rd</sup>-order sensitivities are significantly larger than their corresponding 1<sup>st</sup>- and 2<sup>nd</sup>-order ones, which is contrary to the widely held belief that higher-order sensitivities are all much smaller and hence less important than the first-order ones, for reactor physics systems. In particular, the largest 3<sup>rd</sup>-order relative sensitivity is the mixed sensitivity <img src="Edit_754b8437-dfdf-487d-af68-c78c637e6d4e.png" width="180" height="24" alt="" />of the PERP leakage response with respect to the lowest energy-group (30) total cross sections of <sup>1</sup>H (“isotope 6”) and <sup>239</sup>Pu (“isotope 1”). These two isotopes are shown in this work to be the two most important parameters affecting the PERP benchmark’s leakage response. By comparison, the largest 1<sup>st</sup>-order sensitivity is that of the PERP leakage response with respect to the lowest energy-group total cross section of isotope <sup>1</sup>H, having the value <img src="Edit_a5cfcc11-6a99-41ee-b844-a5ee84b454b3.png" width="100" height="24" alt="" />, while the largest 2<sup>nd</sup>-order sensitivity is <img src="Edit_05166a2b-97f7-43f1-98ff-b21368c00228.png" width="120" height="22" alt="" />. The 3<sup>rd</sup>-order sensitivity analysis presented in this work is the first ever such analysis in the field of reactor physics. The consequences of the results presented in this work on the uncertainty analysis of the PERP benchmark’s leakage response will be presented in a subsequent work. 展开更多
关键词 Polyethylene-Reflected Plutonium Sphere 1st-order Sensitivities 2nd-order Sensitivities 3rd-order Sensitivities Third order Adjoint Sensitivity Analysis Microscopic Total Cross Sections
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九宫腹部经络推拿法用于胸腰椎压缩性骨折便秘患者的效果 被引量:23
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作者 周静 孟登科 +3 位作者 吴蔚 李艳苑 毛金平 郑敏霞 《护理学杂志》 CSCD 北大核心 2019年第14期33-35,共3页
目的观察九宫腹部经络推拿法联合苁蓉通便口服液治疗胸腰椎压缩性骨折便秘的效果。方法将60例胸腰椎压缩性骨折便秘患者随机分为治疗组和对照组各30例。对照组30例采用苁蓉通便口服液治疗,治疗组30例采用九宫腹部经络推拿联合苁蓉通便... 目的观察九宫腹部经络推拿法联合苁蓉通便口服液治疗胸腰椎压缩性骨折便秘的效果。方法将60例胸腰椎压缩性骨折便秘患者随机分为治疗组和对照组各30例。对照组30例采用苁蓉通便口服液治疗,治疗组30例采用九宫腹部经络推拿联合苁蓉通便口服液治疗,观察两组患者的治疗效果及首次排便时间、间隔排便时间、72h排便次数。结果治疗组疗效显著优于对照组,且首次排便时间、间隔排便时间显著短于对照组,72h排便次数显著多于对照组(P<0.05,P<0.01)。结论九宫腹部经络推拿法联合苁蓉通便口服液治疗胸腰椎压缩性骨折便秘疗效显著。 展开更多
关键词 胸腰椎压缩性骨折 便秘 苁蓉通便口服液 九宫 经络 推拿 排便时间
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非高斯信号的非因果非最小相位ARMA模型辨识 被引量:2
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作者 李会方 郝重阳 俞卡章 《西北工业大学学报》 EI CAS CSCD 北大核心 1995年第3期418-422,共5页
提出了一种新的ARMA模型参数辨识方法,该方法以受噪声污染的系统输出信号的三阶矩和双谱作为工具,通过求解一系列线性方程组,分别估计出ARMA模型的MA部分和AR部分的参数。其主要特点在于应用了基本域内的所有双谱采样,... 提出了一种新的ARMA模型参数辨识方法,该方法以受噪声污染的系统输出信号的三阶矩和双谱作为工具,通过求解一系列线性方程组,分别估计出ARMA模型的MA部分和AR部分的参数。其主要特点在于应用了基本域内的所有双谱采样,从而有效的利用了信息量。计算机模拟结果表明,它具有很好的数值特性和较好的参数估计。 展开更多
关键词 双谱 参数估计 信息处理 ARMA模型
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Ba(Zn_((1-x)/3)Ni_(x/3)Nb_(2/3))O_3微波介质陶瓷的微观结构 被引量:1
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作者 石锋 《人工晶体学报》 EI CAS CSCD 北大核心 2009年第2期445-449,共5页
本文采用传统的固相陶瓷烧结工艺,利用Ni2+取代Ba(Zn1/3Nb2/3)O3的B位Zn2+形成固溶体来研究其微观结构。XRD表明,系统的主晶相为立方钙钛矿的BZNN,并有少量第二相如Ba5Nb4O15、BaNb2O6等存在。随Ni2+含量增加,系统晶格常数a减小;而随烧... 本文采用传统的固相陶瓷烧结工艺,利用Ni2+取代Ba(Zn1/3Nb2/3)O3的B位Zn2+形成固溶体来研究其微观结构。XRD表明,系统的主晶相为立方钙钛矿的BZNN,并有少量第二相如Ba5Nb4O15、BaNb2O6等存在。随Ni2+含量增加,系统晶格常数a减小;而随烧结温度升高,a逐渐增大。系统在1500℃下烧结时为固相烧结;当烧结温度为1550℃时,系统由固相烧结转变为液相烧结。较低温度下烧结时,在低角度区有很微弱的1∶2有序相产生;烧结温度升高,无序相增加,有序相消失。 展开更多
关键词 BA(ZN1/3NB2/3)O3 固溶体 微观结构 有序相
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三次多项式温度分布液相模型在液滴蒸发中的应用 被引量:1
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作者 李玮玉 周致富 +2 位作者 陈斌 王国祥 应朝霞 《工程热物理学报》 EI CAS CSCD 北大核心 2017年第5期1012-1016,共5页
三次多项式温度分布模型反映了液滴内部基于希尔球涡的实际流动,可以较为准确地预测单个液滴蒸发。鉴于三次多项式温度分布模型在预测单个液滴蒸发的准确高效性,本文以n-Decane油滴蒸发为例,采用三次多项式模型研究了通过改变初温和初... 三次多项式温度分布模型反映了液滴内部基于希尔球涡的实际流动,可以较为准确地预测单个液滴蒸发。鉴于三次多项式温度分布模型在预测单个液滴蒸发的准确高效性,本文以n-Decane油滴蒸发为例,采用三次多项式模型研究了通过改变初温和初始气流速度来改变初始雷诺数对液滴蒸发的影响,结果表明通过改变气流速度来改变雷诺数的情况,不同雷诺数下液滴蒸发率与内部温度分布存在较大差异;以n-Decane,n-Heptane和n-Dodecane三种不同黏度的油滴蒸发为例,对比了液滴黏度对蒸发的影响,发现不同黏度液滴的蒸发率与内部温度分布差异较大,黏度越小,蒸发率越快;在液滴蒸发的初始阶段,内部温度梯度较大。 展开更多
关键词 液滴蒸发 希尔球涡 三次多项式模型 液滴黏度
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以海泛面进行垂向流动单元划分的方法--以琼东南盆地崖13-1气田陵三段为例 被引量:7
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作者 姜平 李胜利 +3 位作者 李茂文 李茂 黄国政 黄月银 《地学前缘》 EI CAS CSCD 北大核心 2008年第1期154-159,共6页
以层序地层划分为基础,把崖13-1气田主力产层陵三段划分为8个四级层序,并以四级层序的海泛面为控制边界,在气田南区与北II区划分出8个垂向流动单元,而在北I区划分为7个垂向流动单元。崖13-1气田东南部广海海泛对南部地区影响更大,使南... 以层序地层划分为基础,把崖13-1气田主力产层陵三段划分为8个四级层序,并以四级层序的海泛面为控制边界,在气田南区与北II区划分出8个垂向流动单元,而在北I区划分为7个垂向流动单元。崖13-1气田东南部广海海泛对南部地区影响更大,使南区与北II区多沉积了一套海泛面泥岩隔层,导致这两个区块垂向流动单元比北I区多出一个。这一流动单元划分方案得到了气田压力测试的验证,对今后气田开发有指导作用。 展开更多
关键词 崖13—1气田 陵三段 流动单元 海泛面 四级层序
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基于IHF-PLL^(3)rd的混合式步进电机主动式阻尼控制 被引量:1
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作者 施雨 武志涛 佟文明 《中国电机工程学报》 EI CSCD 北大核心 2023年第18期7298-7307,共10页
混合式步进电机本身阻尼极小,在实际运行过程中经常会发生振荡过大、甚至失步的问题。为提高步进电机的控制品质,提出一种基于三阶锁相环(third-orderphaselocked loop,PLL^(3)rd)-积分谐波滤波器(integral harmonic filter,IHF)的步进... 混合式步进电机本身阻尼极小,在实际运行过程中经常会发生振荡过大、甚至失步的问题。为提高步进电机的控制品质,提出一种基于三阶锁相环(third-orderphaselocked loop,PLL^(3)rd)-积分谐波滤波器(integral harmonic filter,IHF)的步进电机主动式阻尼控制方法。首先,主动式阻尼控制是利用同步d-q坐标系调节定子电流,其中控制id恒定为额定电流,调节iq生成瞬时转矩以抑制振荡。其次,为实现转速闭环达到增加电机阻尼的目的,提出一种PLL^(3)rd与IHF相结合的转速观测方法。其中,PLL^(3)rd可消除电机加减速过程中的稳态误差,而IHF可以有效滤除电机反电势中的高次谐波分量,该方法解决了传统微步控制中只减小了振荡幅度但是没有改变控制系统阻尼大小的问题。最后,通过实验验证所提方案的有效性。 展开更多
关键词 混合式步进电机 主动式阻尼控制 三阶锁相环 积分谐波滤波器
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基于HPLC多指标成分定量测定联合化学计量学、熵权优劣解距离法的降糖通脉片质量评价研究 被引量:3
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作者 李平 李新锋 +4 位作者 蔡晓旭 杨红 韩晓静 冀小君 孙立艳 《中草药》 CAS CSCD 北大核心 2023年第8期2417-2426,共10页
目的 采用HPLC法多指标成分定量测定联合正交偏最小二乘-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)及熵权优劣解距离法(entropy weight technique for order preference by similarity to ideal solut... 目的 采用HPLC法多指标成分定量测定联合正交偏最小二乘-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)及熵权优劣解距离法(entropy weight technique for order preference by similarity to ideal solution,EWTOPSIS)对不同厂家降糖通脉片(Jiangtang Tongmai Tablets,JTT)质量进行综合评价,为科学评价JTT质量提供参考。方法 收集3个厂家15批JTT样品,采用HPLC法同时测定JTT中3’-羟基葛根素、葛根素、3’-甲氧基葛根素、太子参环肽B、哈巴苷、哈巴俄苷、二氢丹参酮Ⅰ、隐丹参酮、丹参酮Ⅰ和丹参酮Ⅱ_(A)的含量,运用SPSS26.0和SIMCA14.1统计软件进行层次聚类分析(hierarchical cluster analysis,HCA)、主成分分析(principal component analysis,PCA)和OPLS-DA,建立JTT HCA、PCA和OPLS-DA模型,获取得分图和载荷图及变量重要性投影(variable importance in projection,VIP)值,筛选并分析影响JTT质量差异的主要物质基础,并运用EW-TOPSIS法对不同厂家JTT进行质量优劣性评价。结果 3’-羟基葛根素、葛根素、3’-甲氧基葛根素、太子参环肽B、哈巴苷、哈巴俄苷、二氢丹参酮Ⅰ、隐丹参酮、丹参酮Ⅰ和丹参酮Ⅱ_(A)分别在5.97~298.50、14.45~722.50、4.89~244.50、0.58~29.00、6.55~327.50、2.46~123.00、1.39~69.50、3.56~178.00、4.25~212.50和7.97~398.50μg/mL(r≥0.999 1)线性关系良好,平均加样回收率(n=9)分别为99.53%、100.10%、98.95%、96.97%、100.03%、98.84%、97.06%、98.37%、99.31%、99.18%,RSD分别为0.71%、0.63%、0.98%、1.47%、0.79%、1.30%、1.26%、1.18%、1.39%、1.55%。化学计量学分析结果显示15批JTT样品聚为3类,同一厂家JTT样品聚为一类,不同生产厂家样品质量存在一定差异;葛根素、丹参酮Ⅰ、哈巴苷和丹参酮Ⅱ_(A)是影响JTT样品质量的主要潜在标志物;EW-TOPSIS法可用于不同厂家JTT质量优劣的评价。结论 建立的HPLC多指标成分定量测定方法操作便捷、结果准确,结合HCA、PCA、OPLS-DA及EW-TOPSIS法可用于JTT质量的综合评价。 展开更多
关键词 降糖通脉片 HPLC 化学计量学 正交偏最小二乘-判别分析 熵权优劣解距离法 质量评价 3’-羟基葛根素 葛根素 3’-甲氧基葛根素 太子参环肽B 哈巴苷 哈巴俄苷 二氢丹参酮Ⅰ 隐丹参酮 丹参酮Ⅰ 丹参酮Ⅱ_(A) 主成分分析
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Hierarchical models for failure analysis of plates bent by distributed and localized transverse loadings 被引量:1
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作者 Erasmo CARRERA Gaetano GIUNTA 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第5期600-613,共14页
The failure analysis of simply supported, isotropic, square plates is addressed. Attention focuses on minimum failure load amplitudes and failure locations, von Mises' equivalent stress along the plate thickness is a... The failure analysis of simply supported, isotropic, square plates is addressed. Attention focuses on minimum failure load amplitudes and failure locations, von Mises' equivalent stress along the plate thickness is also addressed. Several distributed and localized loading conditions are considered. Loads act on the top of the plate. Bi-sinusoidal and uniform loads are taken into account for distributed loadings, while stepwise constant centric and off-centric loadings are addressed in the case of localized loadings. Analysis is performed considering plates whose length-to-thickness ratio a/h can be as high as 100 (thin plates) and as low as 2 (very thick plates). Results are obtained via several 2D plate models. Classical theories (CTs) and higher order models are applied. Those theories are based on polynomial approximation of the displacement field. Among the higher order theories (HOTs) HOTsa models account for the transverse shear deformations, while HOTs models account for both transverse shear and transverse normal deformations. LHOTs represent a local application of the higher order theories. A layerwise approach is thus assumed: by means of mathematical interfaces, the plate is considered to be made of several fictitious layers. The exact 3D solution is presented in order to determine the accuracy of the results obtained via the 2D models. In this way a hierarchy among the 2D theories is established. CTs provide highly accurate results for a/h greater than 10 in the case of distributed loadings and greater than 20 for localized loadings. Results obtained via HOTs are highly accurate in the case of very thick plates for bi-sinusoidal and centric loadings. In the case of uniform and off-centric loadings a high gradient is present in the neighborhood of the plate top. In those cases, LHOTs yield results that match the exact solution. 展开更多
关键词 Failure load von Mises' equivalent stress lsotropic plates Higher order theories (HOTs) Exact 3D solution
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接收机三阶截点原理分析及测试方法探讨 被引量:1
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作者 郭锋 《上海计量测试》 2008年第3期20-23,共4页
介绍接收机存在的两种互调失真及其测试方法,针对最新数字超短波接收机的技术特点,提出一种实用的三阶截点测试方法,并分析该方法的测试原理。
关键词 三阶截点 互调失真 中频带宽 数字接收机 中频滤波器
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Fourth-Order Adjoint Sensitivity Analysis of an OECD/NEA Reactor Physics Benchmark: I. Mathematical Expressions and CPU-Time Comparisons for Computing 1<sup>st</sup>-, 2<sup>nd</sup>- and 3<sup>rd</sup>-Order Sensitivities 被引量:2
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作者 Dan Gabriel Cacuci Ruixian Fang 《American Journal of Computational Mathematics》 2021年第2期94-132,共39页
This work extends to fourth-order previously published work on developing the adjoint sensitivity and uncertainty analysis of the numerical model of a <u>p</u>oly<u>e</u>thylene-<u>r</... This work extends to fourth-order previously published work on developing the adjoint sensitivity and uncertainty analysis of the numerical model of a <u>p</u>oly<u>e</u>thylene-<u>r</u>eflected <u>p</u>lutonium (acronym: PERP) OECD/NEA reactor physics benchmark. The PERP benchmark comprises 7477 imprecisely known (uncertain) model parameters which have nonzero values. These parameters are as follows: 180 microscopic total cross sections;7101 microscopic scattering sections;60 microscopic fission cross sections;60 parameters that characterize the average number of neutrons per fission;60 parameters that characterize the fission spectrum;10 parameters that characterize the fission source;and 6 parameters that characterize the isotope number densities. Previous works have used the adjoint sensitivity analysis methodology to compute exactly and efficiently all of the 7477 first-order and 27,956,503 second-order sensitivities of the PERP benchmark’s leakage response to all of the benchmark’s uncertain parameters. These works showed that largest response sensitivities involve the total microscopic cross sections, which motivated the recent computation of all of the (180)<sup>3</sup> third-order sensitivities of the PERP leakage response with respect to these total microscopic cross sections. It turned out that some of these 3<sup>rd</sup>-order cross sections were far larger than the corresponding 2<sup>nd</sup>-order ones, thereby having the largest impact on the uncertainties induced in the PERP benchmark’s response. This finding has motivated the development of the original 4<sup>th</sup>-order formulas presented in this work, which are valid not only for the PERP benchmark but can also be used for computing the 4<sup>th</sup>-order sensitivities of response of any nuclear system involving fissionable material and internal or external neutron sources. Subsequent works will use the adjoint-based mathematical expressions obtained in this work to compute exactly and efficiently the numerical values of the largest fourth-order sensitivities of the PERP benchmark’s response to the total microscopic cross section and use them for a pioneering fourth-order uncertainty analysis of the PERP benchmark’s response. 展开更多
关键词 Polyethylene-Reflected Plutonium Sphere Benchmark 1st-order 2nd-order 3rd-order Forward Sensitivity Analysis FINITE-DIFFERENCES 1st-order 2nd-order 3rd-order Adjoint Sensitivity Analysis Cross Sections
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Higher Order Willmore Hypersurfaces in Euclidean Space 被引量:3
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作者 Zhen GUO 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2009年第1期77-84,共8页
Let x : Mn^n→ R^n+1 be an n(≥2)-dimensional hypersurface immersed in Euclidean space Rn+1. Let σi(0≤ i≤ n) be the ith mean curvature and Qn = ∑i=0^n(-1)^i+1 (n^i)σ1^n-iσi. Recently, the author show... Let x : Mn^n→ R^n+1 be an n(≥2)-dimensional hypersurface immersed in Euclidean space Rn+1. Let σi(0≤ i≤ n) be the ith mean curvature and Qn = ∑i=0^n(-1)^i+1 (n^i)σ1^n-iσi. Recently, the author showed that Wn(x) = ∫M QndM is a conformal invariant under conformal group of R^n+1 and called it the nth Willmore functional of x. An extremal hypersurface of conformal invariant functional Wn is called an nth order Willmore hypersurface. The purpose of this paper is to construct concrete examples of the 3rd order Willmore hypersurfaces in Ra which have good geometric behaviors. The ordinary differential equation characterizing the revolutionary 3rd Willmore hypersurfaces is established and some interesting explicit examples are found in this paper. 展开更多
关键词 higher-order Willmore functional conformal invariant 3rd order Willmore hypersurface
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表面等离子体无掩膜干涉光刻系统的数值分析(英文) 被引量:5
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作者 董启明 郭小伟 《光子学报》 EI CAS CSCD 北大核心 2012年第5期558-564,共7页
表面等离子体激元具有近场增强效应,可以代替光子作为曝光源形成纳米级特征尺寸的图像.本文数值分析了棱镜辅助表面等离子体干涉系统的参量空间,并给出了计算原理和方法.结果表明,适当地选择高折射率棱镜、低银层厚度、入射波长和光刻... 表面等离子体激元具有近场增强效应,可以代替光子作为曝光源形成纳米级特征尺寸的图像.本文数值分析了棱镜辅助表面等离子体干涉系统的参量空间,并给出了计算原理和方法.结果表明,适当地选择高折射率棱镜、低银层厚度、入射波长和光刻胶折射率,可以获得高曝光度、高对比度的干涉图像.入射波长为431nm时,选择40nm厚的银层,曝光深度可达200nm,条纹周期为110nm.数值分析结果为实验的安排提供了理论支持. 展开更多
关键词 干涉光刻 表面等离子体激元 克莱舒曼结构
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用两单参数李群求3阶自治系统的首次积分 被引量:8
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作者 刘洪伟 管克英 《应用数学学报》 CSCD 北大核心 2006年第3期567-573,共7页
在较一般的条件下,对3阶自治系统给出利用系统所接受的两个单参数李群的生成元计算首次积分的方法.
关键词 3阶自治系统 首次积分 单参数李群
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用两个单参数Lie群求三阶自治系统的积分因子 被引量:2
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作者 李方方 胡彦霞 《应用数学学报》 CSCD 北大核心 2011年第1期33-39,共7页
给出并证明了利用三阶自治系统接受的两个单参数Lie群的生成元求系统积分因子的方法.
关键词 三阶自治系统 单参数Lie群 积分因子
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RF knock-out extraction in HITFiL 被引量:1
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作者 石健 杨建成 +5 位作者 夏佳文 原有进 李杰 柴伟平 宋明涛 张小虎 《Chinese Physics C》 SCIE CAS CSCD 2012年第10期1004-1008,共5页
A compact facility for cancer therapy has been designed and is presently under construction. A slow beam extraction system using the RF-Knock Out method and 3rd-order resonance is adopted in the synchrotron of this fa... A compact facility for cancer therapy has been designed and is presently under construction. A slow beam extraction system using the RF-Knock Out method and 3rd-order resonance is adopted in the synchrotron of this facility. Eight sextupoles are used, four of them are for correcting the chromaticity and the rest for driving the 3rd-order resonance. In order to save the aperture of vacuum chamber, a 3-magnet bump is adopted during the extraction process. The extraction phase space map and the last 3 turns’ particle trajectory before extraction are given. The matching betatron functions with HEBT (high energy beam transport) are also presented. 展开更多
关键词 RF-knock out slow extraction 3rd order resonance cancer therapy
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3阶齐次线性常微分方程的球面解曲线
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作者 李凤江 《数学的实践与认识》 CSCD 北大核心 2012年第1期205-208,共4页
首先给出3阶齐次线性常微分方程的球面解曲线的定义,然后讨论其球面解曲线与系数函数的关系,最后给出了球面解曲线的几何性质.
关键词 3阶齐次线性常微分方程 球面解曲线 几何性质
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