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基于波粒二相机实现大数因子分解
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作者 王婉莹 商斌 +1 位作者 王川 龙桂鲁 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2007年第S1期163-165,共3页
利用波粒二相机,根据原始的分解算法、量子Shor算法以及经典计算机中的费马算法和莱曼算法,提出了能够进行大数因子分解的几种算法.通过对原始分解算法的改进,使得用原始大数因子分解的问题由N次变为1次完成.通过对费马算法和莱曼算法改... 利用波粒二相机,根据原始的分解算法、量子Shor算法以及经典计算机中的费马算法和莱曼算法,提出了能够进行大数因子分解的几种算法.通过对原始分解算法的改进,使得用原始大数因子分解的问题由N次变为1次完成.通过对费马算法和莱曼算法改进,减少了大数质因子分解过程的计算复杂度.与量子计算机相比,波粒二相机使得在经典上需要指数步完成的算法,在多项式时间内就可以解决,减少了计算复杂度. 展开更多
关键词 波粒二相机 质数分解 计算复杂度
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三维锥束代数重建算法的投影排序方案 被引量:1
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作者 吴琨 潘晋孝 《CT理论与应用研究(中英文)》 2010年第4期61-70,共10页
代数重建算法中的投影访问顺序对重建图像的收敛速度和精度有很大的影响。针对三维锥束代数重建算法,比较了几种投影序列排序方案的重建图像收敛速度:顺序访问方案,多水平级排序方案,素数分解排序方案,加权距离排序方案。通过仿真实验... 代数重建算法中的投影访问顺序对重建图像的收敛速度和精度有很大的影响。针对三维锥束代数重建算法,比较了几种投影序列排序方案的重建图像收敛速度:顺序访问方案,多水平级排序方案,素数分解排序方案,加权距离排序方案。通过仿真实验得到的实验结果表明:在三维锥束ART算法中按照后三种投影序列排序方案排序后的图像重建比顺序访问方案的收敛速度快,并且WDS排序方案的收敛速度最好。 展开更多
关键词 代数重建算法 投影序列排序 图像重建 加权距离 质数分解 多水平级排序
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Effect of Reduction Associated with Organic Matter Decomposition on Magnetic Properties of Red Soils 被引量:5
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作者 DONGRUIBIN ZHANGWEIGUO +2 位作者 LUSHENGGAO YULIZHONG YUJINYAN 《Pedosphere》 SCIE CAS CSCD 2003年第2期103-110,共8页
Five soils derived from different parent materials were sampled from red soilregion of southern China and studied by magnetic methodology to understand to what extent ironreduction would affect soil magnetic propertie... Five soils derived from different parent materials were sampled from red soilregion of southern China and studied by magnetic methodology to understand to what extent ironreduction would affect soil magnetic properties and how iron reduction would affect the magneticminerals in soils. Reduction associated with organic matter decomposition strongly affected soilmagnetic parameters at low pH. The losses of original soil magnetic signals in terms of magneticsusceptibility (X), 'Soft' isothermal remanent magnetization ('Soft' IRM), anhysteretic remanentmagnetization (ARM) and saturation isothermal remanent magnetization (SIRM) at pH 4~6 during thetwo-month saturation treatment, were 66%~94%, 54%~90%, 64%~95% and 33%~83%, respectively. Thesechanges were interpreted as a consequence of substantial dissolution of maghaemite and haematite inthe soils. At pH 10, however, there was no significant magnetic change observed. Moreover, stablesingle domain soil maghaemite grains were also sensitive to reduction, which suggested that bothpedogenic and detrital maghaemite were not stable in acid and reducing environments. Goethite,instead, was the most stable iron form under reducing conditions. 展开更多
关键词 GOETHITE HAEMATITE maghaemite magnetic susceptibility REDUCTION
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Several Properties of p-w-hyponormal Operators 被引量:1
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作者 LI Hai-ying YANG Chang-sen 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第2期195-201,共7页
In this paper, let T be a bounded linear operator on a complex Hilbert H. We give and prove that every p-w-hyponormal operator has Bishop's property(β) and spectral properties; Quasi-similar p-w-hyponormal operat... In this paper, let T be a bounded linear operator on a complex Hilbert H. We give and prove that every p-w-hyponormal operator has Bishop's property(β) and spectral properties; Quasi-similar p-w-hyponormal operators have equal spectra and equal essential spectra. Finally, for p-w-hyponormal operators, we give a kind of proof of its normality by use of properties of partial isometry. 展开更多
关键词 Aluthge transformation Bishop's property(β) quasi-similar w-hyponormal operators p-w-hyponormal operators
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Modeling for mean ion activity coefficient of strong electrolyte system with new boundary conditions and ion-size parameters
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作者 李弥异 方涛 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第7期1169-1177,共9页
A rigorous approach is proposed to model the mean ion activity coefficient for strong electrolyte systems using the Poisson-Boltzmann equation. An effective screening radius similar to the Debye decay length is introd... A rigorous approach is proposed to model the mean ion activity coefficient for strong electrolyte systems using the Poisson-Boltzmann equation. An effective screening radius similar to the Debye decay length is introduced to define the local composition and new boundary conditions for the central ion. The crystallographic ion size is also considered in the activity coefficient expressions derived and non-electrostatic contributions are neglected. The model is presented for aqueous strong electrolytes and compared with the classical Debye-Hfickel (DH) limiting law for dilute solutions. The radial distribution function is compared with the DH and Monte Carlo studies. The mean ion activity coefficients are calculated for 1:1 aqueous solutions containing strong electrolytes composed of alkali halides. The individual ion activity coefficients and mean ion activity coefficients in mixed sol- vents are predicted with the new equations. 展开更多
关键词 Activity coefficient ElectrolyteIon size Poisson-Boltzmann equation
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Theoretical study of n-budding opening-up vesicle based on the spontaneous curvature model 被引量:1
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作者 KANG WenBin ZHANG ShaoGuang +2 位作者 WANG Ying MU YaRong HUANG Cong 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第12期2243-2247,共5页
N-budding lipid vesicles with single holes were analyzed theoretically by taking into account the line tension of membrane with a hole and the bending energy of membranes based on the Spontaneous-Curvature (SC) model.... N-budding lipid vesicles with single holes were analyzed theoretically by taking into account the line tension of membrane with a hole and the bending energy of membranes based on the Spontaneous-Curvature (SC) model. We solved numerically the Euler-Lagrange equation and the boundary conditions holding on the membrane edge to obtain axisymmetric vesicle shapes, which minimize the total energy. The numerical results show that the size of the opening-up vesicle is larger when the line tension is lower. In other words, additive protein molecules reduce the line tension of lipid membranes, such as talin dose. 展开更多
关键词 opening-up vesicle n-budding numerical computation spontaneous curvature model
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A chemometric method to identify selective ion for resolution of overlapping gas chromatography-mass spectrometry signal
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作者 MEI Zhen DU GuoRong +1 位作者 CAI WenSheng SHAO XueGuang 《Science China Chemistry》 SCIE EI CAS 2013年第5期656-663,共8页
A chemometric method to determine selective ion by using non-negative immune algorithm (NNIA) was proposed. In the method, the mutual projections of the chromatographic profiles at different m/z channel are calculat... A chemometric method to determine selective ion by using non-negative immune algorithm (NNIA) was proposed. In the method, the mutual projections of the chromatographic profiles at different m/z channel are calculated using NNIA. Suppose a GC-MS data with m retention time points and n mass channels, the projections of the GC-MS data onto a chromatographic profile at a mass channel will form a mass spectrum of ln vector. If the chromatographic profile at a selective mass channel is used, the extracted mass spectrum will be a correct one. Therefore, by comparing the extracted mass spectrum with a reference spectrum, the selective ion can be identified, and the corresponding chromatographic profile can be obtained at the same time. GC-MS data of 40-pesticide mixture was investigated by the method. The results show that both the mass spectral and the chromatographic information of the interested components can be extracted from the overlapping signals, except for the special cases of isomeric components with very similar mass spectra. 展开更多
关键词 gas chromatography-mass spectrometry selective ion detection immune algorithm CHEMOMETRICS resolution of overlapping peak
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Analytic solution to the magnetotelluric response over anisotropic medium and its discussion 被引量:3
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作者 QIN LinJiang YANG ChangFu CHEN Kun 《Science China Earth Sciences》 SCIE EI CAS 2013年第9期1607-1615,共9页
In the present paper,from the second order partial differential equations for solving the magnetotelluric(MT) fields of general anisotropic medium,we first obtained the second order partial differential equations for ... In the present paper,from the second order partial differential equations for solving the magnetotelluric(MT) fields of general anisotropic medium,we first obtained the second order partial differential equations for some anisotropic media with special conductivity(e.g.diagonal anisotropy,transverse anisotropy,azimuthal anisotropy,etc.) by simplifying the electrical conductivity tensor of anisotropic medium.And then we obtained the analytic solutions to MT fields for the case of transverse and azimuthal anisotropy through converting the conductivity parameter based on that of diagonal anisotropy.We further discussed the influence of the selection of integral limit and step length on precision in solving the analytic solutions for MT fields of isotropic medium.Finally,we presented the MT responses of two transverse and azimuthal anisotropic media as well as some applications of the analytic solutions to MT fields of anisotropic medium. 展开更多
关键词 Analytic solution to the magnetotelluric response over anisotropic medium and its discussion
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