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Research in Astronomy and Astrophysics 2022年第12期22卷 322-334页

作者： shun-Yi Lan Kai-Fan ji Xiang-Cun Meng Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China

Accreting neutron star binary(ANSB)systems can provide some important information about neutron stars(NSs),especially on the structure and the equation of state of ***,only a few ANSBs are known so *** upcoming Chinese Space Station Telescope(CSST)provides an opportunity to search for a large number of ANSB *** aim to investigate whether or not a machine learning method may efficiently search for ANSBs based on CSST photometric *** this paper,we generate some ANSBs and normal binaries under CSST photometric system by binary evolution and binary population synthesis method and use a machine learning method to train a classification *** consider the classical multi-color disk and the irradiated accretion disk,then compare their effects on the classification *** find that no matter whether the X-ray reprocessing effect is included or not,the machine learning classification accuracy is always very high,i.e.,higher than 96%.If a significant magnitude difference exists between the accretion disk and the companion of an ANSB,machine learning may not distinguish it from some normal stars such as massive main sequence stars,white dwarf binaries,*** classifications of the ANSBs and the normal stars highly overlap in a color–color *** results indicate that machine learning would be a powerful way to search for potential ANSB candidates from the CSST survey.

关键词： stars:neutron X-rays:binaries methods:analytical

Approximate Symmetry Reduction for Initial-value Problems of the Extended KdV-Burgers Equations with Perturbation

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Chinese Physics Letters 2011年第3期28卷 1-4页

作者： LI ji-Na ZHANG shun-Li Center for Nonlinear Studies Department of MathematicsNorthwest UniversityXi’an 710069 Center of Nonlinear Science Ningbo UniversityNingbo 315211

Approximate generalized conditional symmetry is developed to study the approximate symmetry reduction for initial-value problems of the extended KdV-Burgers equations with *** equations can be reduced to initial-value problems for some systems of first-order perturbed ordinary differential equations in terms of a new *** classification theorems are obtained and an example is taken to show the main reduction procedure.

关键词： perturbation. value symmetry

A method to Estimate Dynamic Responses of VLFS Based on Multi-Floating-Module Model Connected by Elastic Hinges

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China Ocean Engineering 2021年第5期35卷 687-699页

作者： HUANG Heng CHEN Xu-jun LIU jun-yi MIAO Yu-ji ji Song College of Field Engineering Army Engineering University of PLANanjing 210007China China Ship Scientific Research Center Wuxi 214082China

Based on the elastic foundation beam theory and the multi-floating-module hydrodynamic theory,a novel method is proposed to estimate the dynamic responses of VLFS(Very Large Floating Structure).In still water,a VLFS can be simplified as an elastic foundation beam model or a multi-floating-module model connected by elastic *** to equivalent displacement of the two models in static analysis,the problem of rotation stiffness of elastic hinges can be ***,based on the potential flow theory,the dynamic responding analysis of multi-floatingmodule model under wave loads can be computed in ANSYS-AQWA *** assembling the time domain analysis results of each module,the dynamic responses of the VLFS can be *** of the method is conducted through a series of comparison calculations,which mainly includes a continuous structure and a three-part structure connected by hinges in regular *** results of this paper method show a satisfactory agreement with the experiment and calculation data given in relative references.

关键词： Very Large Floating Structure(VLFS) dynamic responses elastic foundation beam multi-floatingmodule model elastic hinge

Synthesis and Structural Characterization of [(h^5-C_5Me_5)_2Mo_2Fe_2S_4Br_2]

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Chinese Journal of Structural Chemistry 2002年第1期21卷 34-37页

作者： YU Hong ji shun-jun Lang jian-Ping② (Department of Chemistry and Chemical Engineering, Suzhou University, Suzhou 215006, China) Department of Chemistry and Chemical Engineering Suzhou University Suzhou 215006

The reactions of [(h5-C5Me5)Mo(StBu)3] with equimolar FeBr3 in THF afforded a neutral tetranuclear cluster [(h5-C5Me5)2Mo2Fe2S4Br2] 1. The structure of 1 was determined by single-crystal X-ray diffraction analysis. 1 crystallizes in the monoclinic space group P21/n (No. 14) with a = 9.691(2), b = 15.204(2), c = 18.850(2) ? b = 96.44(1), V = 2759.8(7) ?, Z = 4, Mr = 862.08, Dc = 2.075 g/cm3, F(000) = 1680, m (MoKa) = 51.31 cm-1 and T = 296.2 K. With the use of 3667 observed reflections (I > 3.0s(I)), the structure was refined to R = 0.041 and Rw = 0.051. 1 is composed of a distorted Mo2Fe2S4 cubane core with two Br atoms and two h5-C5Me5 groups coordinating at the Fe and Mo sites, respectively. The lengths of MoMo and FeFe bonds are 2.826 and 2.773 ? respectively the mean length of MoFe bond is 2.751 ?

关键词： synthesis crystal structure molybdenum cluster iron cluster

Structure engineering of PtCu_(3)/C catalyst from disordered to ordered intermetallic compound with heat-treatment for the methanol electrooxidation reaction

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Nano Research 2022年第5期15卷 3866-3871页

作者： Zihao Xing jun Li shun Wang Chenliang Su Huile jin Institute of New Materials&Industry Technology Wenzhou UniversityWenzhou 325024China Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060China

Platinum based alloys are hereinto the mostly used methanol oxidation ***,there are limited ways to improve the methanol oxidation reaction(MOR)performance of catalysts in terms of both activity and *** we developed a simple heat-treatment method to synthesize PtCu_(3)/C intermetallic compound catalyst with lattice *** as-prepared PtCu_(3)/C-1000 exhibited high specific activity of 3.23 mA·cm^(-1) and mass activity of 1,200 mA·mgPt^(-1),which is much higher than the PtCu_(3)/C-untreated and commercial Pt/C catalysts,*** XAS and DFT results shows the high activity of the catalyst towards MOR comes from the tightening of the Pt-M bond,which leads to the decrease of Fermi energy level and the make it difficulty in adsorbing carbon intermediates,thus releasing more active sites to promote the improvement of MOR ***,the PtCu_(3)/C-1000 shows better stability which is due to the surface-rich Pt prevents Cu from dissolution.

关键词： methanol electrooxidation PtCu_(3)alloy catalyst lattice compression composition reconstruction heat-treatment

Integral precession calibration method of PIGA on linear vibration table

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Chinese Journal of Aeronautics 2024年第3期37卷 219-236页

作者： Chuang SUN shun-qing REN jun-wei CAO Ru HUO Department of Automation Tsinghua UniversityBeijing 100084China School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China Faculty of Information technology Beijing University of TechnologyBeijing 100124China

Linear vibration table can provide harmonic accelerations to excite the nonlinear error terms of Pendulous Integrating Gyro Accelerometer(PIGA).Integral precession calibration method is proposed to calibrate PIGA on a linear vibration table in this *** on the precise expressions of PIGA’s inputs,the error calibration model of PIGA is *** angular velocity errors of PIGA are suppressed by integer periodic precession and the errors caused by non-integer periods vibrating are *** complete calibration process,including planning,preparation,PIGA testing,and coefficient identification,is designed to optimize the test operations and evaluate the calibration *** effect of the main errors on calibration uncertainty is analyzed and the relative sensitivity function is proposed to further optimize the test *** and simulation results verify that the proposed 10-position calibration method can improve calibration uncertainties after compensating for the related *** order of calibration uncertainties of the second-and third-order coefficients are decreased to 10^(-8)(rad.s^(-1))/g^(2)and 10^(-8)(rad.s^(-1))/g3,*** with the other two classical calibration methods,the calibration uncertainties of PIGA’s nonlinear error coefficients can be effectively reduced and the proportional residual errors are decreased less than 3×10-6(rad.s^(-1))/g by using the proposed calibration method.

关键词： PIGA Linear vibration table Vibration measurement Calibration Error analysis Uncertainty analysis

Weighted Moore-Penrose inverses and fundamental theorem of even-order tensors with Einstein product

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Frontiers of Mathematics in China 2017年第6期12卷 1319-1337页

作者： jun ji Yimin WEI Department of Mathematics Kennesaw State University Marietta GA 30060 USA School of Mathematical Sciences and Shanghai Key Laboratory of Contemporary Applied Mathematics ~-hldan University Shanghai 200433 China

We treat even-order tensors with Einstein product as linear operators from tensor space to tensor space, define the mill spaces and the ranges of tensors, and study their relationship. We extend the fundamental theorem of linear algebra for matrix spaces to tensor spaces. Using the new relationship, we characterize the least-squares （M） solutions to a multilineax system and establish the relationship between the minimum-norm （N） leastsquares （M）solution of a multilinear system and the weighted Moore-Penrose inverse of its coefficient tensor. We also investigate a class of even-order tensors induced by matrices and obtain some interesting properties.

关键词： Fundamental theorem weighted Moore-Penrose inverse multi- linear system null space and range tensor equation

Gut perforation after orthotopic liver transplantation in adults

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World Journal of Gastroenterology 2007年第14期13卷 2125-2128页

作者： jun Xiong Shen You Xiao-shun He Organ Transplantation Center 1^st Affiliated Hospital Sun Yat-Sen University Guangzhou 510080 Guangdong Province China

AIM： To describe cases of gut perforation after orthotopic liver transplantation.METHODS： Data were colleted from our center database and medical records. Six of 187 patients （3.2%）who underwent orthotopic liver transplantation from January to December 2005 developed gut *** patients were male with an average age of 46 *** piggyback liver transplantation was performed at the Organ Transplantation Center, First Affiliated Hospital, Sun Yat-Sen ***： Previous operation, steroid therapy, and prolonged portal venous cross clamp time, poor nutritional status and iatrogenic injury were found to be its ecological factors. The patients with gut perforation were found to have fever, increased leukocytes, mild abdominal pain and tenderness. The median portal venous clamp time was 63 min （range 45-72 min）,median cold ischaemia time was 11.3 h （range 7-15 h）.Median intraoperative blood loss was 500 mL （range 100-1200 mL） and median operation time was 8.8 h （range 6-12 h）. None of the six patients developed acute cellular rejection. White cell count was above 18 × 10^9/L in five patients （neutrophilic leukocytes were above 90%） and 1.5 × 10^9/L in one patient. Bacterial culture in drainage liquid revealed enterococci in five patients. Of the 6 patients undergoing orthotopic liver transplantation, 3 survived and 3 died after modified piggyback liver transplantation.CONCLUSION： Gut perforation occurs after orthotopic liver transplantation in adults. A careful and minimal dissection during OLT, longer retention of the stomach tube, and reducing the portal clamp time and steroid dose should be taken into consideration. If gut perforation is not prevented, then early diagnosis,preferably through detection of enterococci may ensure better survival.

关键词： Orthotopic liver transplantation Gut perforation Enterococcus faecalis

Design and optimization of diffraction-limited storage ring lattices based on many-objective evolutionary algorithms

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Nuclear Science and Techniques 2023年第10期34卷 20-35页

作者： He-Xing Yin jia-Bao Guan shun-Qiang Tian ji-Ke Wang The Institute for Advanced Studies Wuhan UniversityWuhan 430072China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

Multi-objective evolutionary algorithms(MOEAs) are typically used to optimize two or three objectives in the accelerator field and perform well. However, the performance of these algorithms may severely deteriorate when the optimization objectives for an accelerator are equal to or greater than four. Recently, many-objective evolutionary algorithms(MaOEAs)that can solve problems with four or more optimization objectives have received extensive attention. In this study, two diffraction-limited storage ring(DLSR) lattices of the Extremely Brilliant Source(ESRF-EBS) type with different energies were designed and optimized using three MaOEAs and a widely used MOEA. The initial population was found to have a significant impact on the performance of the algorithms and was carefully studied. The performances of the four algorithms were compared, and the results demonstrated that the grid-based evolutionary algorithm(GrEA) had the best *** OEAs were applied in many-objective optimization of DLSR lattices for the first time, and lattices with natural emittances of 116 and 23 pm·rad were obtained at energies of 2 and 6 GeV, respectively, both with reasonable dynamic aperture and local momentum aperture(LMA). This work provides a valuable reference for future many-objective optimization of DLSRs.

关键词： Storage ring lattices Many-objective evolutionary algorithms GrEA algorithm NSGA

Synchronization of networked multibody systems using fundamental equation of mechanics

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Applied Mathematics and Mechanics(English Edition) 2016年第5期37卷 555-572页

作者： jun LIU jinchen ji jin ZHOU Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai 200072China Department of Mathematics Jining UniversityQufu 273155Shandong ProvinceChina Faculty of Engineering and Information Technology University of Technology SydneyNSW 2007Australia Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai 200072China

From the analytical dynamics point of view, this paper develops an optimal control framework to synchronize networked multibody systems using the fundamental equation of mechanics. A novel robust control law derived from the framework is then used to achieve complete synchronization of networked identical or non-identical multibody systems formulated with Lagrangian dynamics. A distinctive feature of the developed control strategy is the introduction of network structures into the control requirement. The control law consists of two components, the first describing the architecture of the network and the second denoting an active feedback control strategy. A corresponding stability analysis is performed by the algebraic graph theory. A representative network composed of ten identical or non-identical gyroscopes is used as an illustrative example. Numerical simulation of the systems with three kinds of network structures, including global coupling, nearest-neighbour, and small-world networks, is given to demonstrate effectiveness of the proposed control methodology.

关键词： fundamental equation of mechanics analytical dynamics synchronization,networked multibody system gyrodynamics coordinate control