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The research of Digital Holographic Object Wave Field Reconstruction in Image and Object Space

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Chinese Physics Letters 2011年第6期28卷 114-117页

作者： li jun-chang PENG Zu-Jie FU Yun-chang Faculty of Science Kunming University of Science and TechnologyKunming 650093

For conveniently detecting objects of different sizes using digital holography,usual measurements employ the object wave transformed by an optical system with different magnifications to fit charge coupled devices(CCDs),then the object field reconstruction involves the diffraction calculation of the optic wave passing through the optical *** propose two methods to reconstruct the object *** one is that,when the object is imaging in an image space in which we reconstruct the image of the object field,the object field can be expressed according to the object-image *** other is that,when the object field reaching CCD is imaged in an object space in which we reconstruct the object field,the optical system is described by introducing matrix optics in this *** reconstruction formulae which easily use classic diffraction integral are ***,experimental verifications are also accomplished.

关键词： image optics passing

Data-driven parity-time-symmetric vector rogue wave solutions of multi-component nonlinear Schrödinger equation

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Chinese Physics B 2022年第6期31卷 137-144页

作者： li-jun chang Yi-Fan Mo li-Ming ling De-Lu Zeng School of Mathematics South China University of TechnologyGuangzhou 510640China

Rogue waves are a class of nonlinear waves with extreme amplitudes,which usually appear suddenly and disappear without any ***,the parity-time(PT)-symmetric vector rogue waves(RWs)of multi-component nonlinear Schrödinger equation(n-NLSE)are usually derived by the methods of integrable *** this paper,we utilize the multi-stage physics-informed neural networks(MS-PINNs)algorithm to derive the data-driven symmetric vector RWs solution of coupled NLS system in elliptic and X-shapes domains with nonzero boundary *** results of the experiment show that the multi-stage physics-informed neural networks are quite feasible and effective for multi-component nonlinear physical systems in the above domains and boundary conditions.

关键词： nonlinear Schrödinger equation vector rogue waves deep learning numerical simulations

Construction of Prokaryotic Expression Vector of Mouse Nanog Gene and Its Expression

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Agricultural Sciences in China 2007年第4期6卷 487-492页

作者： li jun Lü chang-rong DOU lin DOU Zhong-ying Shaanxi Center of National Stem Cell Engineering ＆ Technology Center Northwest A＆F University Yangling 712100 P.R.China

The aim of this study is to construct a prokaryotic expression vector of mouse Nanog gene and to express it in E. coli. A pair of primers was designed according to digestion sites in plasmid pGEX-KG and the Nanog gene sequence published by GenBank. The DNA fragment of 918 bp was amplified by polymerase chain reaction （PCR） from the pNA992 recombinant plasmid with Nanog gene, then cloned into pGEX-KG and transformed into the host E. coli strain TG Ⅰ. The sequence of the fragment was matched with the original sequence of pNA992. It indicated that fusion expression vector, pGEX-KG- Nanog, was constructed successfully. The pGEX-KG-Nanog plasmid was extracted from E. coli strain TG Ⅰ and was transformed into BL21（DE3） for expression. After induction by isopropyl-β-D-thiogalactoside （IPTG） at 37℃, the expression product of Nanog gene was identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE）, and the expression condition was optimized. Nanog fusion protein was successfully expressed in the form of inclusion bodies. The molecular weight of the inclusion body was 63 kDa. Meanwhile, the optimum condition for the expression of Nanog fusion protein was induced with 0.8 mmol L^-1 IPTG for 5 h. The mouse Nanog gene was successfully expressed in E. coli, which laid a foundation for the purification of Nanog protein and for the preparation of polyclonal antibody.

关键词： Nanog gene prokaryotic expression glutathione-S-transferase (GST) fusion protein mouse

Heredity and gene mapping of a novel white stripe leaf mutant in wheat

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Journal of Integrative Agriculture 2021年第7期20卷 1743-1752页

作者： li Hui-juan JIAO Zhi-xin Nl Yong-jing JIANG Yu-mei li jun-chang PAN Chao ZHANG Jing SUN Yu-long AN jun-hang liU Hong-jie li Qiao-yun NIU Ji-shan National Centre of Engineering and Technological Research for Wheat/National Key Laboratory of Wheat and Maize Crop Science/Henart Agricultural University Zhengzhou 450046P.R.China Shangqiu Academy of Agricultural and Forestry Sciences Shangqiu 476000P.R.China

Spotted leaf(spl)mutant is a type of leaf lesion mimic mutants in *** obtained some lesion mimic mutants from ethyl methane sulfonate(EMS)-mutagenized wheat(Triticum aestivum L.)cultivar Guomai 301(wild type,WT),and one of them was named as white stripe leaf(wsl)mutant because of the white stripes on its *** we report the heredity and gene mapping of this novel wheat mutant *** are many small scattered white stripes on the leaves of wsl throughout its whole growth *** the plants grew,the white stripes became more severe and the necrotic area *** mutant wsl grew only weakly before the jointing stage and gradually recovered after *** length and width of the flag leaf,spike number per plant and thousand-grain weight of wsl were significantly lower than those of the *** analysis indicated that the trait of white stripe leaf was controlled by a recessive gene locus,named as wsl,which was mapped on the short arm of chromosome 6 B by SSR marker *** SSR markers in the F2 population of wsl×CS were linked to wsl in the order of Xgpw1079–Xwmc104–Xgwm508-wsl–Xgpw7651 at 7.1,5.2,8.7,and 4.4 c M,respectively and three SSR markers in the F2 population of wsl×Jimai 22 were linked to wsl in the order of Xgwm508–Xwmc494–Xgwm518-wsl at 3.5,1.6 and 8.2 c M,*** comparison to the reference genome sequence of Chinese Spring(CS),wsl is located in a 91-Mb region from 88 Mb(Xgwm518)to 179 Mb(Xgpw7651)on chromosome 6 *** wsl is a novel germplasm for studying the molecular mechanism of wheat leaf development.

关键词： wheat(Triticum aestivum L.) mutant white stripe leaf(wsl) heredity gene mapping

基于相机rawRGB通过加权多项式和维纳估计方法重建光谱反射率

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光谱学与光谱分析 2021年第10期41卷 3281-3285页

作者：李富豪李长军辽宁科技大学计算机与软件工程学院辽宁鞍山114051

基于相机RGB预测物体光谱反射率的研究一直备受研究者们的关注。传统方法都是通过单一光源下的信息进行光谱反射率恢复。最近,Zhang等在Color Research&Application报道了一种基于单光源相机RGB信息预测物体光谱反射率的两步方法。首先... 详细信息

基于相机RGB预测物体光谱反射率的研究一直备受研究者们的关注。传统方法都是通过单一光源下的信息进行光谱反射率恢复。最近,Zhang等在Color Research&Application报道了一种基于单光源相机RGB信息预测物体光谱反射率的两步方法。首先基于单个光源下的相机响应RGB值,挑选出一定量的训练数据,采用多项式模型和伪逆的方法预测出不同光源下的CIE XYZ值;然后根据预测的多光源下的CIE XYZ值及整体训练数据预估光谱反射率,再通过预估的光谱反射率挑选一定量训练样本,通过伪逆方法预测出物体光谱反射率。尽管仍然基于一个光源下的相机响应RGB,但通过映射到多光源下的色度值XYZ,提高输入信息的维度来优化光谱反射率的重建精度。受Zhang等工作的启发,提出新的基于单一光源下相机的raw RGB响应信息,通过三阶多项式模型扩展的加权最小二乘方法对多光源下的CIE XYZ值进行预测,然后根据预测出的多光源下的CIE XYZ值再通过维纳估计的方法进行光谱反射率重建,通过这样的两步方法实现从相机响应RGB到光谱反射率的重构。该新方法,采用全体训练数据,应用十分方便,避免了Zhang等的方法需要挑选一定量的局部训练样本的问题。同时Zhang等的方法挑选出的局部训练样本同等重要,而该方法在第1步中,根据训练样本与给定的测试样本的接近程度,赋予训练样本不同的权重,以提高预测精度。通过采用140色色卡作为训练样本,24色色卡和自制的44色印刷品样本进行测试,以判断预测和实测反射率接近程度的均方根误差(RMSE)和人感知色差为评价标准进行比较,结果表明,该方法明显优于Zhang等的方法,而且预测精度随着光源数量的增加而提高,当光源个数达到6时,表现最佳。

关键词：多光源光谱反射率重建加权维纳估计

Adaptive Modulation with Channel Estimation in High-Speed Packet-Based OFDM Communication Systems

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The Journal of China Universities of Posts and Telecommunications 2004年第z1期11卷 76-82页

作者： HOU Xiao-lin WU jun-li YIN chang-chuan YUE Guang-xin School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China

In this paper, adaptive modulation with channel estimation in high-speed packet-based Orthogonal Frequency Division Multiplexing (OFDM) communication systems for beyond 3G are discussed. Different adaptive modulation and channel estimation methods are presented and compared, then those methods suitable for our intended application are chosen. Conclusions can be drawn from computer simulations that with proper selection of packet length and subband width, wide subband adaptive modulation with Least Square plus Discrete-time Fourier Transform (LS-DFT) channel estimation can give an acceptable performance with low complexity for channel with low Doppler shift and small path delay. Otherwise, narrow subband or subcarrier adaptive modulation together with LS-DFT plus Decision Directed (LS-DFT-DD) must be used.

关键词： OFDM adaptive modulation channel estimation beyond 3G

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散射光数字全息检测过程的统计光学讨论

光子学报 2008年第4期37卷 734-739页

作者：李俊昌昆明理工大学昆明650093

从统计光学及标量衍射的基本理论出发,研究散射光数字全息重构波面与原散射波的关系,提出非平滑物体双曝光全息过程中散射光传播及干涉的简化模型.基于简化模型及计算机数值计算,对一个双曝光全息干涉系统转动形变的检测过程进行了理论... 详细信息

从统计光学及标量衍射的基本理论出发,研究散射光数字全息重构波面与原散射波的关系,提出非平滑物体双曝光全息过程中散射光传播及干涉的简化模型.基于简化模型及计算机数值计算,对一个双曝光全息干涉系统转动形变的检测过程进行了理论模拟,并通过与该系统实验测量的比较,证实了简化模型的可行性.

关键词：信息光学统计光学数字全息散射光数字全息

Thermal Effect of the Cable-Stayed Bridge Tower

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Wuhan University Journal of Natural Sciences 2003年第04A期8卷 1121-1125页

作者： Zhang Hai-long, li jun, liu chang-guo, Jiang Tian-hua, Wei jun School of Civil Engineering and Mechanics, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China Huazhong University of Science and Technology School of Civil Engineering and Mechanics Wuhan Hubei China (GRID:grid.33199.31) (ISNI:***)

This paper studies the thermal effect of the cable-stayed bridge tower based on full time accurate measurement and finite element analysis on Xiantao Hanjiang River Highway Bridge. The measured results and the displacement variation of top tower show that the tower rotates periodically when it is exposed in sunshine. But the tower column will not decline when there is no sunshine. In spite of in winter or in summer, the period when the tower column changed smallest is from 0∶00 am to 5∶00 am. The time period when the tower column has maximum deviation lags behind the time when the tower column has maximum temperature difference, and this phenomenon is obvious in winter. The conclusions also have directive value in predicting the tower deformations and their directions in construction control of cable-stayed bridge, and in verifying the finite element program.

关键词： bridge tower thermal effect deformation full time measurement

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一类改进的鞍点矩阵最大特征值的区间估计

东北大学学报（自然科学版） 2009年第9期30卷 1362-1364,1368页

作者：李铮张铁李长军东北大学理学院辽宁沈阳110004

对鞍点矩阵的特征值估计理论进行了研究.基于对鞍点矩阵的对称性以及鞍点矩阵的最大特征值与子矩阵特征值之间关系的分析,改进了关于鞍点矩阵最大特征值的下界估计,从而得到一类改进的关于鞍点矩阵最大特征值的区间估计.数值实验中考察... 详细信息

对鞍点矩阵的特征值估计理论进行了研究.基于对鞍点矩阵的对称性以及鞍点矩阵的最大特征值与子矩阵特征值之间关系的分析,改进了关于鞍点矩阵最大特征值的下界估计,从而得到一类改进的关于鞍点矩阵最大特征值的区间估计.数值实验中考察了由P1-P0混合有限元方法离散化Stokes方程所导出鞍点矩阵的最大特征值.数值结果表明所给出的关于鞍点矩阵最大特征值的区间估计是有效的.

关键词：鞍点矩阵特征值区间估计混合有限元法 Stokes方程