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991.
We review some recent progress in our understanding of the lowest-lying spin-1/2 and spin-3/2 baryon magnetic moments (MMs) in terms of Chiral Perturbation Theory (ChPT).In particular,we show that at next-to-leading-order ChPT can describe the MMs of the octet baryons quite well.We also make predictions for the decuplet MMs at the same chiral order.Among them,the MMs of the Δ++ and Δ + are found to agree well with data within the experimental uncertainties. 相似文献
992.
贾卢魁 毛泽普 李卫东 曹国富 曹学香 邓子艳 何康林 刘春燕 刘怀民 刘秋光 马秋梅 马想 邱进发 田浩来 王纪科 伍灵慧 袁野 臧石磊 张长春 张雷 张瑶 朱凯 邹佳恒 《中国物理 C》2010,34(12):1866-1873
In order to overcome the difficulty brought by the circling charged tracks with transverse momentum less than 120 MeV in the BESⅢ Main Drift Chamber (MDC), a specialized method called TCurlFinder was developed. This tracking method focuses on the charged track reconstruction under 120 MeV and possesses a special mechanism to reject background noise hits. The performance of the package has been carefully checked and tuned by both Monte Carlo data and real data. The study shows that this tracking method could obviously enhance the reconstruction efficiency in the low transverse momentum region, providing physics analysis with more and reliable data. 相似文献
993.
By using a suitable set of the surface energy coefficient, nuclear radius, and universal function, the original proximity potential 1977 is modified. The overestimate of the data by 4% reported in the literature is significantly reduced. Our modified proximity potential reproduces the experimental data nicely compared to its older versions. 相似文献
994.
Equation of State in the σ-ω-ρ Model Supported by the Observational Data of 4U 1608-52 Neutron Star 下载免费PDF全文
The properties of the neutron star rotating at 619Hz (which is the spin frequency of 4U 1608-52 neutron star) are investigated by using an equation of state (EOS) of the nuclear matter in the relativistic σ-ω-ρ model. It is shown that the EOS in the relativistic σ-ω-ρ model is supported by the observational mass and radius of the 4U 1608-52 neutron star. Moreover, a
strict constraint on the polar redshift of 4U 1608-52 neutron star is obtained. 相似文献
strict constraint on the polar redshift of 4U 1608-52 neutron star is obtained. 相似文献
995.
基于MATLAB及数据库技术的实验数据检验及存取研究 总被引:1,自引:0,他引:1
对无纸化实验进行探讨,大量的实验数据的科学、高效、实用化管理是问题的关键,利用数据库技术解决这一问题。实现了利用MATLAB的图形用户界面(GUI)功能录入并检验实验数据。MATLAB与数据库的连接方法以实现数据通信,给出了通过MATLAB的GUI界面输入的数据存人数据库以及事后再从数据库中把数据取出到MATLAB以备处理的方法,方便实现MATLAB的GUI下实验数据的拟合及结果可视化。实现了MATLAB下实验数据的交互式处理。 相似文献
996.
<正>The dispersion of Yb-doped fiber is measured by a spectral interferometric technique.The experimental verification is achieved by comparing the measured data with published data of the Nufern 1060xp fiber and the measurement relative error is 1.36%.The parameters of the experimental system,such as minimum required source bandwidth and minimum fiber length,are introduced and analyzed in the measurement. The minimum required source bandwidth predicted through theoretical calculation at the center wavelength of 1070 nm is 19.3 nm,which perfectly agrees with the experimental value. 相似文献
997.
Hyperspectral feature recognition based on kernel PCA and relational perspective map 总被引:1,自引:0,他引:1
A novel joint kernel principal component analysis (PCA) and relational perspective map (RPM) method called KPmapper is proposed for hyperspectral dimensionality reduction and spectral feature recognition. Kernel PCA is used to analyze hyperspectral data so that the major information corresponding to features can be better extracted. RPM is used to visualize hyperspectral data through two-dimensional (2D) maps, and it is an efficient approach to discover regularities and extract information by partitioning the data into pieces and mapping them onto a 2D space. The experimental results prove that the KPmapper algorithm can effectively obtain the intrinsic features in nonlinear high dimensional data. It is useful and impressing for dimensionality reduction and spectral feature recognition. 相似文献
998.
<正>A simulation method for visible and near infrared(VNIR) image is mentioned.The VNIR image obtained by low-level flight is adopted as data resource.After atmospheric correction,the ground reflectivity can be deducted.The simulation method consists of four steps:radiative transfer,spatial resolution,modulation transfer function,and noise simulation.The image of satellite-borne or high-level air-borne sensor could be generated by the simulation method from VNIR image.Experiment is carried out to test the method using an airship as platform.The resulting simulated image is compared to the image with quickbird panchromatic band.The result shows that simulation images enables one to effectively reproduce the entire process of remote sensing of the Earth.The method can be used to simulate VNIR image at satellite level at the same area and the same wavelength. 相似文献
999.
为了有效地提高面向逆向工程的工业CT图像轮廓处理的精准性和计算效率,开发了工业CT图像轮廓提取与优化系统。该系统主要包括图像处理模块、轮廓识别与提取模块、轮廓拟合与优化模块、图像处理经典算法库和数据接口等功能模块,实现了从工业CT图像到轮廓数据的三维点云与轮廓线的标准格式输出,并与逆向工程软件对接。同时,在轮廓拟合与优化模块中,提出了基于全局约束模型的轮廓拟合策略,并采用有向图分解和数值代数相结合的计算方法,提高了轮廓拟合的计算精度和效率。最后通过实例验证了系统的有效性和正确性。 相似文献
1000.