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基于超球近似子空间的协同优化方法及应用研究 被引量:14
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作者 李响 李为吉 《西北工业大学学报》 EI CAS CSCD 北大核心 2003年第4期461-464,共4页
针对协同优化的计算结构及计算困难 ,提出了学科间不一致信息概念 ,并据此形成系统级优化的超球设计空间。有效地解决了原始系统级优化问题不满足 Kuhn- Tucker条件造成的计算困难 ,并克服了已有梯度方法计算易发散、响应面方法计算量... 针对协同优化的计算结构及计算困难 ,提出了学科间不一致信息概念 ,并据此形成系统级优化的超球设计空间。有效地解决了原始系统级优化问题不满足 Kuhn- Tucker条件造成的计算困难 ,并克服了已有梯度方法计算易发散、响应面方法计算量大的缺点。利用文中提出的方法对一齿轮减速箱进行了设计 ,实现了并行设计的目的 。 展开更多
关键词 协同优化 学科间不一致信息 空间
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改进的超球支持向量机算法 被引量:6
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作者 刘爽 陈鹏 《计算机工程与应用》 CSCD 北大核心 2009年第16期149-151,共3页
超球支持向量机算法用于解决多类别数据的分类问题。对超球重叠区域的数据正确分类对球结构支持向量机的分类性能至关重要。在分析这些样本点特点的基础上,提出了一种新的分类规则,使超球支持向量机算法的泛化性能高于现有的算法。实验... 超球支持向量机算法用于解决多类别数据的分类问题。对超球重叠区域的数据正确分类对球结构支持向量机的分类性能至关重要。在分析这些样本点特点的基础上,提出了一种新的分类规则,使超球支持向量机算法的泛化性能高于现有的算法。实验结果表明该算法有效可行,提高了最小包围球分类器的分类精度。 展开更多
关键词 支持向量机 多分类问题 重叠区域数据 子超球
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基于超球支持向量机的水环境质量评价 被引量:1
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作者 陈昱奇 潘俊 +1 位作者 董健 张宗禹 《供水技术》 2015年第2期5-9,共5页
将超球向量机方法引用到水环境质量评价中,并应用该方法与标准指数法分别对细河水体进行了评价。结果表明,超球向量机评价方法对监测值处于分类重叠区域的水质分类要优于标准指数法,评价结果更客观,具有较好的泛化能力,说明超球向量机... 将超球向量机方法引用到水环境质量评价中,并应用该方法与标准指数法分别对细河水体进行了评价。结果表明,超球向量机评价方法对监测值处于分类重叠区域的水质分类要优于标准指数法,评价结果更客观,具有较好的泛化能力,说明超球向量机法可以用于水环境质量评价,具有很好的研究前景。 展开更多
关键词 水环境质量评价 支持向量机 向量机 子超球 分类重叠区
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MODELING OF SCG ROTOR DRIFT AND MEASURING SCHEME 被引量:1
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作者 汤继强 房建成 张延顺 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第1期17-24,共8页
Based on micro-displacement measurement principles of the spherical differential capacitance sensor, the relationship between the capacitance variation and the micro-displacement of each pair of detecting electrodes f... Based on micro-displacement measurement principles of the spherical differential capacitance sensor, the relationship between the capacitance variation and the micro-displacement of each pair of detecting electrodes for the superconducting gyroscope (SCG) with eight detecting electrodes is analyzed. The model of the SCG rotor drift is established through dimensionless processing, linearization within micro-displacement and the least-square approach. Both the measurement scheme of the SCG rotor drift based on the model and its parameter relationship are presented. To guarantee the potential of the suspension rotor to be zero, the distributing scheme of four pairs of detecting electrodes is presented. The scheme can measure the magnitude and the direction of the rotor drift. The negative factors for affecting the measurement precision of .the SCG rotor drift and simulation results of the total effects are given. Simulation results show that the distributing capacitance of these differential capacitance sensors, the zero potential of the rotor and the model error are the major negative factors. The methods for eliminating those negative factors and the application range of the model are given. The model ensures the relationship between the output voltage and the rotor drift be linear. 展开更多
关键词 superconducting gyroscope suspension rotor DRIFT spherical differential capacitance MICRO-DISPLACEMENT
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Synthesis and Properties of Micron-size Magnetic Polymer Spheres with Epoxy Groups 被引量:8
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作者 刘先桥 官月平 +2 位作者 邢建民 马志亚 刘会洲 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第6期731-735,共5页
Micron-size superparamagnetic poly(styrene-divinylbenzene-glycidyl methacrylate) (PSt-DVB-GMA) spheres were prepared via a modified suspension copolymerization method. Oleic acid coated magnetite (Fe3O4 nanoparticles ... Micron-size superparamagnetic poly(styrene-divinylbenzene-glycidyl methacrylate) (PSt-DVB-GMA) spheres were prepared via a modified suspension copolymerization method. Oleic acid coated magnetite (Fe3O4 nanoparticles made by co-precipitation were first mixed with monomers of St, DVB, GMA, and benzoyl peroxide (BPO) to form oil in water suspension with the presence of poly(viny) pyrrolidone) (PVP-K30) as a stabilizer. Then the temperature of mixture was increased at a controlled rate to obtain small and relatively uniform droplets. Finally, the copolymerization reaction was initiated by the decomposition of BPO. The morphology and properties of magnetic PSt-DVB-GMA microspheres were examined by SEM, TEM, VSM, XRD and FT-IR. The magnetic microspheres obtained have very small size (about 4-7μm) in diameter with narrow size distribution and super-paramagnetic characteristics. Powder X-ray diffraction measurements show the inverse cubic spinel structure for the magnetite dispersed in polymer microspheres. FT-IR spectroscopy indicates extensive oxirane groups existed on the surface of magnetic PSt-DVB-GMA microspheres. 展开更多
关键词 magnetic microsphere SYNTHESIS suspension polymerization BIOSEPARATION
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Monodisperse Ultra-Large-Pore Silica Coated Polystyrene Core-Shell Microbeads via Layer-by-Layer Assembly for Nano-Micro Composite
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作者 谢闯 刘逸卿 +4 位作者 李泓达 郝红勋 王永莉 尹秋响 王静康 《Transactions of Tianjin University》 EI CAS 2015年第5期420-426,共7页
Polystyrene (PS) @SiO2 core-shell microbeads with large pore and large particle size were prepared via layer-by-layer(LBL)assembly technique for potential applications in nano-micro composites. Negative silica nan... Polystyrene (PS) @SiO2 core-shell microbeads with large pore and large particle size were prepared via layer-by-layer(LBL)assembly technique for potential applications in nano-micro composites. Negative silica nanoparticles synthesized via modified St6ber method and cationic poly (diallyldimethylammonium chloride) were alternately adsorbed on the surface of microbeads. Zeta potential, size, and morphology of the microbeads were monitored during LBL assembly process to ensure the successful deposition of silica nanoparticles. The porous shell was characterized using nitrogen adsorption and desorption analyses, and the surface area, volume and diame- ter of the pores were derived. It is found that the porous shell thickness and the pore size can be tuned by changing the coating times of silica nanoparticles. Finally, PS@SiO2 core-shell microbeads with 5 grn PS solid core and 350 nm mesoporous shell (mean BJH pore diameter is ~27 nm) were used to load CdSe/ZnS quantum dots (QDs). The fluorescence microscopic image and the optical amplification of the QDs-embedded microbeads (QDBs) indicate that the as-prepared core-shell microbeads can provide adequate space for QDs and may be useful for further application of nano-micro composites. 展开更多
关键词 large pore mesoporous silica core-sheU structure MICROBEADS layer-by layer assembly nano-microcomposite amplified spontaneous emission
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Spherical Kadomtsev-Petviashvili Solitons in a Suprathermal Complex Plasma
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作者 Mehran Shahmansouri Jafar Borhanian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第8期227-232,共6页
The nonlinear aspects of nonplanar dust acoustic (DA) solitary waves are investigated in an unmagnetized complex plasma comprising of cold dust grains,kappa-distributed ions as well as electrons.The nonplanar DA solit... The nonlinear aspects of nonplanar dust acoustic (DA) solitary waves are investigated in an unmagnetized complex plasma comprising of cold dust grains,kappa-distributed ions as well as electrons.The nonplanar DA solitons are studied based on the reductive perturbation technique.It is shown that the evolution of DA solitons is governed by a spherical Kadomtsev-Petviashvili (sKP) equation and then the impact of suprathermality on the spatial structure as well as the nature of DA soliton is studied.It seems that the properties of DA solitons in nonplanar geometry are quite different from that of the planar solitons. 展开更多
关键词 dust-acoustic solitons superthermal ion/electron nonplanar waves
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Can all the recurrence relations for spherical functions be extended to spheroidal functions 被引量:1
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作者 TIAN GuiHua LI ZhaoYang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第10期1775-1782,共8页
There are two kinds of recurrence relations for the spherical functions Pml. The first are those with the same m but different l. Thesecond are those with the same l but different m. The spheroidal functions are exten... There are two kinds of recurrence relations for the spherical functions Pml. The first are those with the same m but different l. Thesecond are those with the same l but different m. The spheroidal functions are extensions of the spherical functions. Recurrencerelations of the first kind are obtained for the spheroidal functions in recent studies. Using the shape invariance method in super-symmetric quantum mechanics, we investigate the second type of recurrence relations for the spheroidal functions. The resultsshow that the second kind of recurrence relation can not be extended to the spheroidal functions. 展开更多
关键词 spheroidal wave functions supersymmetry quantum mechanics super-potential shape-invariance
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Detection of Supernova Neutrinos on the Earth for Large θ_(13)
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作者 徐晶 黄明阳 +2 位作者 胡立军 郭新恒 杨炳麟 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第2期226-234,共9页
Supernova (SN) neutrinos detected on the Earth are subject to the shock wave effects, the Mikheyev- Smirnov-Wolfenstein (MSW) effects, the neutrino collective effects and the Earth matter effects. Considering the ... Supernova (SN) neutrinos detected on the Earth are subject to the shock wave effects, the Mikheyev- Smirnov-Wolfenstein (MSW) effects, the neutrino collective effects and the Earth matter effects. Considering the recent experimental result about the large mixing angle 013 (-8.8°) provided by the Daya Bay Collaboration and applying the available knowledge for the neutrino conversion probability in the high resonance region of SN, PH , which is in the form of hypergeometric function in the case of large 813, we deduce the expression of PH taking into account the shock wave effects. It is found that PH is not zero in a certain range of time due to the shock wave effects. After considering all the four physical effects and scanning relevant parameters, we calculate the event numbers of SN neutrinos for the "Garehing" distribution of neutrino energy spectrum. From the numerical results, it is found that the behaviors of neutrino event numbers detected on the Earth depend on the neutrino mass hierarchy and neutrino spectrum parameters including the dimensionless pinching parameter βa (where a refers to neutrino flavor), the average energy 〈Ea〉, and the SN neutrino luminosities La. Finally, we give the ranges of SN neutrino event numbers that will be detected at the Daya Bay experiment. 展开更多
关键词 supernova neutrinos Daya Bay experiment 813 shock wave effects MSW effects PH
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