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B-Spline with Symplectic Algorithm Method for Solution of Time-Dependent Schrodinger Equations 被引量:2
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作者 卞学滨 乔豪学 史庭云 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第9期2403-2406,共4页
A B-spline with the symplectic algorithm method for the solution of time-dependent Schrodinger equations (TDSEs) is introduced. The spatial part of the wavefunction is expanded by B-spline and the time evolution is ... A B-spline with the symplectic algorithm method for the solution of time-dependent Schrodinger equations (TDSEs) is introduced. The spatial part of the wavefunction is expanded by B-spline and the time evolution is given in a symplectic scheme. This method allows us to obtain a highly accurate and stable solution of TDSEs. The effectiveness and efficiency of this method is demonstrated by the high-order harmonic spectra of one-dimensional atoms in comparison with other references. 展开更多
关键词 ORDER HARMONIC-GENERATION MULTIPHOTON IONIZATION QUANTUM SYSTEM LASERFIELDS SCHEME ATOM
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P波初动包络线增长率区域特征的初步讨论
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作者 廉超 孔宇阳 陈新强 《大地测量与地球动力学》 CSCD 北大核心 2018年第2期157-160,共4页
使用B-Δ方法对日本东北地区265个地震事件进行分析,得到该地区P波初动包络线增长率,研究其区域差异特性。利用P波初动2~3s的数据,通过经验公式预测地震震中距;通过对P波初动波形拟合公式Bt·exp(-At)得到拟合参数A和B;在确定公式... 使用B-Δ方法对日本东北地区265个地震事件进行分析,得到该地区P波初动包络线增长率,研究其区域差异特性。利用P波初动2~3s的数据,通过经验公式预测地震震中距;通过对P波初动波形拟合公式Bt·exp(-At)得到拟合参数A和B;在确定公式斜率值后,得到经验系数c值。结果显示,该地区记录到的地震波P波包络线增长率存在一定的深度依赖性,深度较小的地震得到较小的c值,即表现出较为平缓的P波包络线增长率;深度较大的地震得到较大的c值,即表现出较为陡峭的P波包络线增长率。 展开更多
关键词 地震预警系统 b-△方法 区域差异特征
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Calculation and Analysis of Near Field of Airborne Short Wave Antenna
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作者 薛正辉 高本庆 +2 位作者 刘瑞祥 吕昕 杨力 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期286-292,共7页
Aim To calculate and analyze the near field distribution of ariborne short wave antenna. Methods B-spline method was used to get the mathermatital model of a Boeing 707320Baircraft and simulate its short wave antenna ... Aim To calculate and analyze the near field distribution of ariborne short wave antenna. Methods B-spline method was used to get the mathermatital model of a Boeing 707320Baircraft and simulate its short wave antenna . FDTD (finite-difference time-domain) method are ed tO complete the calculation and analysis. Results The near field distributions on aircraft's surface were obtained, the curve and gray figures of the normalized near field value were shown. Conclusion These modeling and calculating methods can provide data foraircraft's EMC analysis and design. 展开更多
关键词 airborne short antenna near field distribution FDTD method b-SPLINE
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Candidal liver abscesses and cholecystitis in a 37-year-old patient without underlying malignancy 被引量:2
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作者 Chung-HsuLai Hsin-PaiChen +3 位作者 Te-LiChen Chang-PhoneFung Cheng-YiLiu Shou-DongLee 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第11期1725-1727,共3页
We report a case of candidal liver abscesses and concomitant candidal cholecystitis in a diabetic patient, in whom differences were noted relative to those found in patients with hematologic malignancies. In our case,... We report a case of candidal liver abscesses and concomitant candidal cholecystitis in a diabetic patient, in whom differences were noted relative to those found in patients with hematologic malignancies. In our case, the proposed entry route of infection is ascending retrograde from the biliary tract. Bile and aspirated pus culture repeatedly tested positive, and blood negative, for Candida albicans and Candida glabrata. Cholecystitis was cured by percutaneous gallbladder drainage and amphotericin B therapy. The liver abscesses were successfully treated by a cumulative dosage of 750 mg amphotericin B. We conclude that in cases involving less immunocompromised patients and those without candidemia, a lower dosage of amphotericin B may be adequate in treating candidal liver abscesses. 展开更多
关键词 CANDIDA Liver abscess CHOLECYSTITIS Amphotericin B Endoscopic papillotomy Biliary prosthesis
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Nonfactorizable B→xcoK Decay and QCD Factorization
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作者 MENG Ce GAO Ying-Jia CHAO Kuang-Ta 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5X期885-890,共6页
We study the unexpectedly large rate for the factorization-forbidden decay B →xcoK within the QCD factorization approach. We use a non-zero gluon mass to regularize the infrared divergences in vertex corrections. The... We study the unexpectedly large rate for the factorization-forbidden decay B →xcoK within the QCD factorization approach. We use a non-zero gluon mass to regularize the infrared divergences in vertex corrections. The end-point singularities arising from spectator corrections are regularized and carefully estimated by the off-shellness of quarks. We find that the contributions arising from the vertex and leading-twist spectator corrections are numerically small, and the twist-3 spectator contribution with chiral enhancement and linear end-point singularity becomes dominant. With reasonable choices for the parameters, the branching ratio for B → XcoK decay is estimated to be in the range (2 ~ 4)× 10^-4, which is compatible with the Belle and BaBar data. 展开更多
关键词 B meson decay QCD factorization CHARMONIUM
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Generalized solutions to the Benjamin-Ono equations in sense of Colombeau
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作者 金小刚 杨建刚 蔺杰 《Journal of Zhejiang University Science》 CSCD 2004年第11期1466-1470,共5页
This paper discusses the existence and uniqueness of the generalized solution in the sense of Colombeau to the Benjamin-Ono (B-O) equation and the relationship between the new generalized solution and the classical so... This paper discusses the existence and uniqueness of the generalized solution in the sense of Colombeau to the Benjamin-Ono (B-O) equation and the relationship between the new generalized solution and the classical solution. 展开更多
关键词 b-O equation Algebra of generalized solution Hilbert transform
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Estimates of Soil Organic Carbon Stocks in Zhejiang Province of China Based on 1:50000 Soil Database Using the PKB Method 被引量:2
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作者 ZHI Jun-Jun JING Chang-Wei +2 位作者 LIN Sheng-Pan ZHANG Cao WU Jia-Ping 《Pedosphere》 SCIE CAS CSCD 2015年第1期12-24,共13页
Soil organic carbon(SOC) is an important component of farming systems and global carbon cycle. Accurately estimating SOC stock is of great importance for assessing soil productivity and modeling global climate change.... Soil organic carbon(SOC) is an important component of farming systems and global carbon cycle. Accurately estimating SOC stock is of great importance for assessing soil productivity and modeling global climate change. A newly built 1:50 000 soil database of Zhejiang Province containing 2 154 geo-referenced soil profiles and a pedological professional knowledge-based(PKB) method were used to estimate SOC stock up to a depth of 100 cm for the Province. The spatial patterns of SOC stocks stratified by soil types,watershed(buffer analysis), topographical factors, and land use types were identified. Results showed that the soils in Zhejiang covered an area of 100 740 km2 with a total SOC stock of 831.49 × 106 t and a mean SOC density of 8.25 kg m-2, excluding water and urban areas. In terms of soil types, red soils had the highest SOC stock(259.10 × 106t), whereas mountain meadow soils contained the lowest(0.15 × 106t). In terms of SOC densities, the lowest value(5.11 kg m-2) was found in skel soils, whereas the highest value(45.30 kg m-2) was observed in mountain meadow soils. Yellow soils, as a dominant soil group, determined the SOC densities of different buffer zones in Qiantang River watershed because of their large area percentage and wide variation of SOC density values.The area percentages of various soil groups significantly varied with increasing elevation or slope when overlaid with digital elevation model data, thus influencing the SOC densities. The highest SOC density was observed under grassland, whereas the lowest SOC density was identified under unutilized land. The map of SOC density(0–100 cm depth) and the spatial patterns of SOC stocks in the Province would be helpful for relevant agencies and communities in Zhejiang Province, China. 展开更多
关键词 ELEVATION pedological professional knowledge-based method sampling depth SLOPE SOC density soil groups
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A strain smoothing formulation for NURBS-based isogeometric finite element analysis 被引量:2
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作者 WANG DongDong ZHANG HanJie XUAN JunChang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第1期132-140,共9页
A strain smoothing formulation for NURBS (non-uniform rational B-splines) based isogeometric finite element analysis is presented. This approach is formulated within the framework of assumed strain methods and strain ... A strain smoothing formulation for NURBS (non-uniform rational B-splines) based isogeometric finite element analysis is presented. This approach is formulated within the framework of assumed strain methods and strain smoothing operations. The strain smoothing is defined through strain averaging in the element sub-domains which are subsequently used for numerical integration of the Galerkin weak form. This formulation satisfies the orthogonality condition of the assumed strain methods. Meanwhile the present formulation totally avoids the gradient computation of the rational NURBS basis functions in the formulation of stiffness matrix. A transformation method is employed to accurately enforce the displacement boundary conditions. Numerical results demonstrate that the present formation gives very satisfactory solution accuracy simultaneously with improved computational efficiency. 展开更多
关键词 NURBS basis functions isogeometric finite element analysis meshfree method strain smoothing sub-domain integration
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Multi-neighboring grids schemes for solving PDE eigen-problems 被引量:5
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作者 SUN JiaChang 《Science China Mathematics》 SCIE 2013年第12期2677-2700,共24页
Instead of most existing postprocessing schemes, a new preprocessing approach, called multi- neighboring grids (MNG), is proposed for solving PDE eigen-problems on an existing grid G(A). The linear or multi-linear... Instead of most existing postprocessing schemes, a new preprocessing approach, called multi- neighboring grids (MNG), is proposed for solving PDE eigen-problems on an existing grid G(A). The linear or multi-linear element, based on box-splines, are taken as the first stage Khuh -λh/1Mh/1Uh. In this paper, the j-th stage neighboring-grid scheme is defined as Khuh λh/j Mh/j Uh = λh/j Mh/j Uh , where gh :- Mh/j-1 Kh/1 and Mhuh is to be found as a better mass distribution over the j-th stage neighboring-grid G(/k), and Kh/1 can be seen as an expansion of Kh on the j-th neighboring-grid with respect to the (j - 1)-th mass distribution Mh_l. It is shown that for an ODE model eigen-problem, the j-th stage scheme with 2j-th order B-spline basis can reach 2j-th order accuracy and even (2j + 2)-th order accuracy by perturbing the mass matrix. The argument can be extended to high dimensions with separable variable cases. For Laplace eigen-problems with some 2-D and 3-D structured uniform grids, some 2j-th order schemes are presented for j ≤ 3. 展开更多
关键词 PDE eigen-problem discrete Rayleigh quotient multi-neighboring grids schemes b-SPLINES
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Quality-control method for the determination of biological activity of engineered calcineurin subunit B
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作者 Xinchang Shi Huan Yang +5 位作者 Li Xu Xiang Li Zongwen Huang Yudong Han Qun Wei Chunming Rao 《Science China(Life Sciences)》 SCIE CAS CSCD 2016年第6期584-588,共5页
The aim of this study was to establish a quality-control method for calcineurin subunit B(CNB) biological activity determinations. CNB enhances the p-nitrophenylphosphate(p NPP) dephosphorylating activity of calcineur... The aim of this study was to establish a quality-control method for calcineurin subunit B(CNB) biological activity determinations. CNB enhances the p-nitrophenylphosphate(p NPP) dephosphorylating activity of calcineurin subunit A Δ316 mutant(CNAΔ316). A series of CNB concentrations were fitted to a four-parameter equation to calculate the corresponding p NPP maximum dephosphorylation rates. Values were calculated based on biological activity references using a parallel line method. The method was then validated for accuracy, precision, linearity, linear range, sensitivity, specificity, and robustness. The recovery results were greater than 98%. Intra-plate precision was 6.7%, with inter-plate precision of 10.8%. The coefficient of determination was greater than 0.98. The linear range was 0.05–50 μg m L?1, with sensitivity of 50 μg m L?1. Tested cytokines did not induce CNAΔ316 dephosphorylation of p NPP. The chosen CNAΔ316 concentration range did not affect activity determinations. 展开更多
关键词 calcineurin subunit B biological activity method establishment method validation quality control
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