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Chinese Journal of Aeronautics 2021年第1期34卷 1-9页

作者： jing CUI Tao SHEN Tao WEI Zhongyi CHU School of Mechanical Engineering and Applied Electronics Beijing University of TechnologyBeijing 100124China School of Instrumental Science ami Opto-electronics Engineering Beihang UniversityBeijing 100191China Shenzhen Polytechnic Shenzhen 518055China

The space debris occupies the orbit resources greatly,which seriously threats the safety of spacecraft for its high risks of *** theories about space debris removal have been put forward in recent *** Electro Dynamic Tether(EDT),which can be deployed under gravity gradient,is considered to be an effective method to remove debris in low orbit for its low power ***,in order to generate sufficient Lorentz force,the EDT needs to be deployed to several kilometers,which increases the risks of tangling and the instability of the EDT *** the deployment process,different initial in-plane/out-of-plane angles,caused by direction error at initial release or the initial selection of ejection,affect the motion of EDT system *** order to solve these problems,firstly,this paper establishes the dynamic model of the EDT ***,based on the model,safety metrics of avoiding tangling and assessing system stability during EDT deployment stage are designed to quantitatively evaluate the EDT system ***,several numerical simulations are established to determine the safety ranges of the initial in-plane/out-of-plane angles on the EDT deployment.

关键词： Assembly the electrodynamics tether system Electrodynamics tether deployment In-plane/out-of-plane angles Tangling risks

Pseudo-break imaging of carbon nanotubes for determining elastic bending energies

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Nano Research 2023年第5期16卷 7443-7451页

作者： Changfei jing Yongji qin Wengen Ouyang Jun Luo Institute for New Energy Materials and Low-Carbon Technologies and Tianjin Key Lab of Photoelectric Materials and Devices School of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China ShenSi Lab Shenzhen Institute for Advanced StudyUniversity of Electronic Science and Technology of ChinaShenzhen 518110China Department of Engineering Mechanics School of Civil EngineeringWuhan UniversityWuhan 430072China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China

One-dimensional(1D)nanomaterials easily bend due to perturbations from their surroundings or their own *** phenomenon not only impacts the performances of various devices but has also been employed to develop a variety of new functional devices,in which the bending energies of the nanomaterials determine the device ***,measuring the energies of such nanomaterials is extremely ***,pseudo-break imaging of 1D nanomaterials has been proposed and realized on individual carbon nanotubes(CNTs),in which a CNT appears to break and has a fracture but is actually *** imaging approach provides the values of the bending energies of the CNTs with an accuracy of 1–50 ***,this imaging approach can manipulate the bending shapes and energies of *** work presents a protocol for bending analysis and manipulation,which are vital to fundamental and applied studies of 1D nanomaterials.

关键词： pseudo-break imaging carbon nanotube electron microscopy elastic bending energy

An innovative inertial parameters identification method for non-cooperative space targets based on electrostatic interaction

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Chinese Journal of Aeronautics 2024年第9期37卷 417-432页

作者： Heng jing Zixuan ZHENG Dejia CHE Jianping YUAN National Key Laboratory of Aerospace Flight Dynamics Northwestern Polytechnical UniversityXi'an 710072China School of Astronautics Northwestern Polytechnical UniversityXi'an 710072China

Inertial characteristics of non-cooperative targets are crucial for space capture and sub-sequent on-orbit *** methods for identifying inertial parameters involve proximity operations,which are associated with the risk of collision with non-cooperative *** paper introduces a long-range,contactless method for identifying the inertial parameters of a non-cooperative target during the pre-capture ***,electrostatic interaction is used as an external excitation to alter the target's motion.A force estimation algorithm that uses measure-ments from visual and potential sensors is proposed to estimate the electrostatic interaction and eliminate the need for force ***,a recursive estimation-identification framework is presented to concurrently estimate the coupled motion state,weak electrostatic interaction,and inertial parameters of the *** simulation results show that the proposed method extends the identification distance to 170 times that of the previous method while maintaining high identifica-tion precision forall parameters.

关键词： Non-cooperative target Inertial parameters identification Electrostatic interaction Force estimation Dynamical coupling

Influence of cerium treatment on inclusion modification and as-cast microstructure of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2022年第10期29卷 1659-1668页

作者： Ru-ming Geng jing Li Cheng-bin Shi State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China

The influence of cerium treatment on the inclusion evolution and as-cast microstructure of high-strength low-alloy steel was *** including the inclusions characteristics,element distribution,and the in situ solidification were analyzed by scanning electron microscopy,energy-dispersive spectroscopy,and high-temperature confocal laser scanning microscopy,*** results indicated that,after the addition of Ce,the Al_(2)O_(3) inclusions evolved to form Ce_(2)O_(2)S and CeAlO_(3) inclusions,which exhibited a decrease in size alongside corresponding increase in their number *** equiaxed grain ratio exhibited by the as-cast microstructure increased significantly upon the addition of Ce,while a reduction in the segregation and a corresponding increase in the homogeneity of the carbon distribution within the as-cast microstructure were also *** results of the in situ observation of the solidification suggested that the addition of Ce significantly reduced the solidification temperature range,thus reducing the carbon *** nucleation effect imparted by Al_(2)O_(3),Ce_(2)O_(2)S,and CeAlO_(3) on theδ-Fe formation was discussed in the context of the disregistry theory,which revealed that the formation of a large number of fine Ce_(2)O_(2)S inclusions promotedδ-Fe formation via heterogeneous nucleation.

关键词： Ce treatment Non-metallic inclusion As-cast microstructure In situ observation Disregistry theory

Self-assembled aggregations in Coptidis Rhizoma decoction dynamically regulate intestinal tissue permeability through Peyer's patch-associated immunity

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Chinese Herbal Medicines 2021年第3期13卷 370-380页

作者： qing-qing Zhang Ye Yang Rong-rong Ren qing-qing Chen jing-jing Wu Yu-yu Zheng Xiao-hui Hou Yu-feng Zhang Ming-song Xue Deng-ke Yin School of Pharmacy Anhui University of Chinese MedicineHefei 230012China Institute of Pharmaceutics Anhui Academy of Chinese MedicineHefei 230012China Engineering Technology Research Center of Modernized Pharmaceutics Education Office of Anhui ProvinceHefei 230012China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China

Objective:To investigate the dynamic regulation of self-assembled aggregations(SAA)in Coptidis Rhizoma decoction on the permeability of intestinal tissue and the mechanism ***:The effects of SAA on berberine(Ber)absorption were respectively analyzed in an in situ intestinal perfusion model and in an Ussing Chamber jejunum model with or without Peyer’s patches(PPs).The expression levels of ZO-1,Occludin and Claudin-1 were detected by immunofluorescence to evaluate the tight junction(TJ)between intestinal epithelium *** expression levels of T-box-containing protein expressed in T cells,signal transducers and activators of tranion-6,retinoic acid receptor-related orphan receptor ct and forkhead box P3 in PPs were detected by the reverse transcription-polymerase chain reaction and the secretions of interferon-c(IFN-c),interleukin-4(IL-4),interleukin-17(IL-17)and transforming growth factor-b(TGF-b)in PPs were evaluated by immunohistochemistry,to reflect the differentiation of T lymphocyte in PPs to helper T(Th)cell 1,Th2,Th17 and regulatory T(Treg)*** confirm the correlation between SAA in Coptidis Rhizoma decoction,PPs-associated immunity and intestinal epithelium permeability,SAA were administrated on an Ussing Chamber jejunum model with immunosuppressed PPs and evaluated its influences on intestinal tissue permeability and TJ proteins ***:SAA in Coptidis Rhizoma decoction could dose-dependently promote Ber absorption in jejunum segment,with the participation of *** dose-dependent and dynamical regulations of SAA on permeability of intestinal tissue and TJ proteins expression level between intestinal epithelium cells occurred along with the dynamically changed T lymphocyte differentiation and immune effectors secretion in *** administration of SAA on immunosuppressed PPs exhibited dose-dependent PPs activation,inducing dynamic promotion on intestinal tissue permeability and inhibition on TJ proteins ***:

关键词： Coptidis Rhizoma decoction intestinal absorption intestinal mucosal immunity Peyer’s patches self-assembled aggregations

Learning dynamics of gradient descent optimization in deep neural networks

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Science China(Information Sciences) 2021年第5期64卷 17-31页

作者： Wei WU Xiaoyuan jing Wencai DU Guoliang CHEN School of Computer Science Wuhan University Institute of Data Science City University of Macau College of Computer Science and Software Engineering Shenzhen University

Stochastic gradient descent(SGD)-based optimizers play a key role in most deep learning models,yet the learning dynamics of the complex model remain obscure. SGD is the basic tool to optimize model parameters, and is improved in many derived forms including SGD momentum and Nesterov accelerated gradient(NAG). However, the learning dynamics of optimizer parameters have seldom been studied. We propose to understand the model dynamics from the perspective of control theory. We use the status transfer function to approximate parameter dynamics for different optimizers as the first-or second-order control system, thus explaining how the parameters theoretically affect the stability and convergence time of deep learning models, and verify our findings by numerical experiments.

关键词： learning dynamics deep neural networks gradient descent control model transfer function

Cross-modality PET/CT and contrast-enhanced CT imaging for pancreatic cancer

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World Journal of Gastroenterology 2015年第10期21卷 2988-2996页

作者： Jian Zhang Chang-jing Zuo Ning-Yang Jia Jian-Hua Wang Sheng-Ping Hu Zhong-Fei Yu Yuan Zheng An-Yu Zhang Xiao-Yuan feng Department of Nuclear Medicine Changhai Hospital Second Military Medical University Department of Radiology Eastern Hepatobiliary Surgery HospitalSecond Military Medical University Department of Radiology the Affiliated Hospital of Medical School of Ningbo University Department of PET/CT Center No.411 Hospital of PLA Department of Radiology No.85 Hospital of PLA Department of Radiology Huashan HospitalFudan University

AIM:To explore the diagnostic value of the crossmodality fusion images provided by positron emission tomography/computed tomography(PET/CT) and contrast-enhanced CT(CECT) for pancreatic cancer(PC).METHODS:Data from 70 patients with pancreatic lesions who underwent CECT and PET/CT examinations at our hospital from August 2010 to October 2012were ***/CECT for the cross-modality image fusion was obtained using Ture D *** diagnostic efficiencies of PET/CT,CECT and PET/CECT were calculated and compared with each other using aχ2 test.P0.05for each).In 17 of the 50 patients with PC confirmed by histology or clinical follow-up,distant metastasis was *** differences in the sensitivity and NPV between CECT and PET/CECT in detecting distant metastasis were statistically significant(P<0.05 for each).CONCLUSION:Cross-modality image fusion of PET/CT and CECT is a convenient and effective method that can be used to diagnose and stage PC,compensating for the defects of PET/CT and CECT when they are conducted individually.

关键词： Pancreatic neoplasms Positron-emission tomography

护理领域混合方法研究的设计要点及典型问题分析

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中华护理杂志 2024年第3期59卷 261-266页

作者：胡雁荆凤复旦大学护理学院上海市200032

混合方法研究范式在护理学研究领域的应用增加,丰富了护理研究方法学的多样性,但在应用中存在混合的逻辑性模糊、研究设计不严谨、结果整合薄弱等问题。该文主要分析了护理领域混合方法研究的设计类型、资料整合及常见问题,以促进该研... 详细信息

混合方法研究范式在护理学研究领域的应用增加,丰富了护理研究方法学的多样性,但在应用中存在混合的逻辑性模糊、研究设计不严谨、结果整合薄弱等问题。该文主要分析了护理领域混合方法研究的设计类型、资料整合及常见问题,以促进该研究范式在护理领域中的规范应用和发展。

关键词：护理研究混合方法研究设计类型资料整合

“啃老”:事实还是偏见——基于中国4城市青年调查数据的实证分析

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人口与发展 2011年第5期17卷 57-64页

作者：宋健戚晶晶中国人民大学人口与发展研究中心北京100872

青年的"啃老"现象引起了广泛的社会关注。基于家庭代际交换理论,从日常生活及住房两个维度,量化界定"啃老"概念,对中国已婚青年的"啃老"现状进行实证研究,探索影响因素及其强度,特别关注独生子女与流动人口群体的"啃老"特征。中国已婚... 详细信息

青年的"啃老"现象引起了广泛的社会关注。基于家庭代际交换理论,从日常生活及住房两个维度,量化界定"啃老"概念,对中国已婚青年的"啃老"现状进行实证研究,探索影响因素及其强度,特别关注独生子女与流动人口群体的"啃老"特征。中国已婚青年确实存在较为普遍的"啃老"行为,但主要表现在住房资源维度;独生子女在住房及日常的家庭代际交换中更倾向于"啃老"和"强啃老";流动减少了青年的"啃老"风险,但未显著提高其对父代的赡养可能性。已婚青年的年龄、受教育程度、户口性质、经济收入与父代特征等也是显著的影响因素。

关键词： “啃老” 家庭代际交换已婚青年独生子女流动人口

Mathematical model and simulated annealing algorithm for Chinese high school timetabling problems under the new curriculum innovation

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Frontiers of Computer Science 2021年第1期15卷 167-177页

作者： Xingxing HAO jing LIU Yutong ZHANG Gustaph SANGA Key Laboratory of Intelligent Perception and Image Understanding of Ministry of Education Xidian UniversityXi’an 710071China

As the first attempt,this paper proposes a model for the Chinese high school timetabling problems(CHSTPs)under the new curriculum innovation which was launched in 2011 by the Chine6e *** 10 the new our riculum innovation,students in high school can choose subjects that they are interested in instead of being forced to select one of the two study directions,namely,Science and Liberal ***,they also need to attend compulsory subjects as *** are student-oriented and involve more student constraints that make them more complex than the typi-cal"Class-Teacher model",in which the element"Teacher"is the primary *** this paper,we first describe in detail the mathematical model of CHSTPs and then design a new two-part representation for the candidate *** on the new representation,we adopt a two-phase simulated annealing(SA)algorithm to solve CHSTPs.A total number of 45 synthetic instances with different amounts of classes,teachers,and levels of student constraints are generated and used to ilustrate the characteristics of the CHSTP model and the effectiveness of the designed representation and ***,we apply the proposed model,the designed two-part representation and the two-phase SA on10 real high schools.

关键词： timetabling Chinese high school timetabling problem simulated annealing two-part representation