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基于置信规则库和弹道仿真的加速度计健康状态评估

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控制与决策 2024年第9期39卷 3143-3150页

作者：廉正胡来红周志杰胡昌华陈雷雨明志超火箭军工程大学导弹工程学院西安710025

结合加速度计运行机理复杂,测试样本少的特点,提出一种基于置信规则库(BRB)和弹道仿真的健康状态评估模型.首先,基于BRB建立初始的健康状态评估模型,由于定性知识的主观性,初始的评估模型难以提供准确的评估结果而需要被优化,然而,在以... 详细信息

结合加速度计运行机理复杂,测试样本少的特点,提出一种基于置信规则库(BRB)和弹道仿真的健康状态评估模型.首先,基于BRB建立初始的健康状态评估模型,由于定性知识的主观性,初始的评估模型难以提供准确的评估结果而需要被优化,然而,在以往的研究中优化所需的健康状态真实值一般通过专家给定,存在模糊性和不精确的问题,因此,根据加速度计在导航过程中的物理模型,基于弹道仿真方法准确地计算其健康状态的真实值;然后,基于协方差自适应进化算法(P-CMA-ES),健康状态真实值被用于初始评估模型的优化,从而准确、快速地进行健康状态评估;最后,以某型加速度计的健康状态评估为例,验证所提出方法的有效性.

关键词：加速度计健康状态评估置信规则库弹道仿真

Effect of Reclamation on the Groundwater-Lake Water Interaction in chen Lake

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Journal of Earth Science 2024年第3期35卷 1083-1086页

作者： Kun lei Teng Ma Liuzhu chen Zhenxing Li yu chen School of Environmental Studies State Key Laboratory of Biogeology and Environmental GeologyChina University of GeosciencesWuhan 430078China

0 INTRODUCTION To relieve the short supply of suitable land for residing,cultivating,and commerce,it is accepted to reclaim land from lakes,river estuaries,and coastal regions in many countries(Mancini et al.,2020).The large-scale reclamation activities have an irreversible effect on the mico-geomorphology and hydrodynamic system of seasonally flooded areas(Zhang et al.,2019;yu et al.,2018).For example,coastal regions reclaimed extended the groundwater flow paths,as well as created groundwater level rise,resulting in water-logging in the reclaimed area(Hu et al.,2008).Similar changes in groundwater flow systems may alter groundwater-lake water interactions,and it can ultimately affect the water cycle in the lake ***,such detailed studies are presently *** addition,natural exchanges between the lake and groundwater systems can be strongly affected by physical hydrological processes(Javadzadeh et al.,2020),chemical properties(Kamtchueng et al.,2015),and bioto behavior(Hancock et al.,2005).

关键词： groundwater coastal logging

Structural Characterization and Luminescence Properties of Two 4d-4fLn-Ag Coordination Compounds Based on Dinuclear Lanthanide Clusters

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Chemical Research in Chinese Universities 2014年第2期30卷 194-199页

作者： ZHANG yu chen lei JU Weiwei XU Yan State Key Laboratory of Materials-oriented Chemical Engineering College of Chemistry and Chemical EngineeringNanjing Tech University Nanjing 210009 P.R.China

Two new compounds,[ErAg（INA）2（C2O4）]·2H2O（1）（HINA=nicotinic acid） and [Tb0.8Y0.2Ag2（IN）4·（H2O）5]·NO3·2H2O（2）（HIN=isonicotinic acid）,based on the {Ln2} building units,have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction,infrared spectroscopy,thermal analysis and powder X-ray diffraction（PXRD）.Single-crystal X-ray diffraction data reveal that both compounds crystallized in the low-symmetry triclinic space group P1-.Compound 1 is a 3D heterometallic coordination framework based on {Er2}clusters,oxalate ligands and bridging [Ag（INA）] linkers,while compound 2 consists of 0D [Tb0.8·Y0.2Ag2（IN）4（H2O）5]2 subunits that give a 3D supramolecular structure through hydrogen bond *** photoluminescent properties of both compounds（1 and 2） were studied.

关键词： 4d-4fLn-Ag coordination compound Doping Hydrothermal synthesis Crystal structure

Effect of DH treatment on microstructure and mechanical properties of an LM28-0.3wt.%Nd hypereutectic aluminum silicon alloy

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Rare Metals 2007年第6期26卷 578-583页

作者： GAO Bo chen lei yu Fuxiao SUN Shuchen TU Ganfeng School of Materials and Metallurgy Northeastern University Shenyang 110004 China

In this article, a novel heat treatment method, deformation heat （DH） treatment （extrusion ＋ aging）, was employed on a hypereutectic aluminum silicon alloy （LM28-0.3wt.%Nd）, and its effect on microstructure and mechanical properties of this alloy was investigated. It can be concluded that the eutectic microstructure disappears after the DH treatment, in the meantime the morphology of α（Al） solid solution was transformed from fir-troe and cellular to equiaxed, Si was refined with grain sizes of about 1-10 μn and distributed dispersedly, even some of them became globular shape, which can reduce stress accumulation effectively. Mechanical properties test indicated that the DH treatment could significantly improve the room-ternperature strength and have little effect on the high-temperature strength of LM28-0.3wt.%Nd alloy. The fracture mechanism is ductile fracture by fracture morphology analysis.

关键词： Al-Si alloys Nd deformation heat treatment mechanical properties

普通专升本学生的身份认同研究:基于教师访谈的质性分析

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深圳职业技术大学学报 2024年第2期23卷 45-53页

作者：陈兆军陈玉蕾郭建鹏厦门大学教育研究院福建厦门361005 烟台南山学院山东省社会科学普及教育基地山东龙口265706

专升本学生是“专科起点本科学习”的群体,他们兼有的专科和本科双重身份招致其自我认知偏颇和社会有色眼光。然而,学生在教师眼中的样子是一种较为客观的“镜中我”。为厘清专升本学生身份认同状况,以齐克瑞大学生自我同一性发展的七... 详细信息

专升本学生是“专科起点本科学习”的群体,他们兼有的专科和本科双重身份招致其自我认知偏颇和社会有色眼光。然而,学生在教师眼中的样子是一种较为客观的“镜中我”。为厘清专升本学生身份认同状况,以齐克瑞大学生自我同一性发展的七向量作为考察要素,对来自8所高校的18位专升本的任课教师进行深度访谈。质性分析结果发现,专升本学生在教师眼中是上进稳重、品格正直的群体;相比普通本科生,他们在动手实践能力、情绪管理、独立自主性、社会性发展等方面具有优势。然而,他们的专业理论基础薄弱、学习自卑心理制约其学业发展和进步;虽然他们就业目标感较强,但缺乏负责任的职业决策,表现出不恰当的职业价值观。建议高校着重加强他们专业理论基础和学习自信心,提升其职业决策能力和社会情感能力,进而增强其自我同一性发展。

关键词：专升本学生身份认同七向量深度访谈

Reduction of unactivated alkyl chlorides enabled by light-induced single electron transfer

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Science China Chemistry 2024年第2期67卷 471-481页

作者： lei Dai Zhao-Fei Zhang Xiang-yu chen School of Chemical Sciences University of the Chinese Academy of SciencesBeijing100049China Institute of Chemistry Chinese Academy of SciencesBeijing100190China Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhou256606China

Alkyl chlorides are abundant and easily accessible starting ***,due to the high reduction potentials associated with unactivated alkyl chlorides,achieving their single electron reduction remains a persistent *** challenge has spurred the exploration of efficient activation methods to overcome this *** recent years,photocatalysis has emerged as a mild and potent tool for the single electron reduction of unactivated alkyl chlorides,opening up new possibilities in this *** the rapid advancements in this area,a comprehensive review that provides a conceptual understanding of this emerging field,with a specific focus on reaction design and catalytic mechanisms,would be timely and highly ***,we present an overview of various synthetic techniques for photoinduced single electron reduction of unactivated alkyl ***,we also discuss the limitations of the present methods and future directions that lie ahead in this field.

关键词： photocatalysis unactivated alkyl chlorides single electron transfer radical reactions

A novel domain decomposition-based model for efficient dynamic predictions of large composite machine tools

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Science China(Technological Sciences) 2024年第6期67卷 1765-1782页

作者： yu YangBo JI yu lei chen YanRen XU Kun BI QingZhen State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240China

We propose a large combined moving component composed of carbon fiber reinforced polymer(CFRP)laminates for making lightweight machine tools with high dynamic *** accurate dynamic prediction of composite machine tools is essential for the new generation machine *** paper aims to address two challenges in numerical dynamic modeling and the design of composite machine tools to enhance development efficiency.(1)Anisotropic composite laminates,which form the composite machine tool,exhibit coupling in various *** propose the generalized continuity condition of the boundary to tackle this dynamic modeling challenge.(2)Composite machine tools feature numerous composite-metal coupled *** mechanical model correction of isotropic metals is performed to address their *** take the example of a five-axis gantry machine tool with composite moving parts,establish a dynamic model for efficient prediction,and verify it through simulation and *** proposed method yields remarkable results,with an average relative error of only 3.85%in modal frequency prediction and a staggering 99.7%reduction in solution time compared to finite element *** further discuss the dynamic performance of the machine tool under varied stacking angles and layer numbers of the composite machine *** propose general design criteria for composite machine tools to consider the modal frequency and manufacturing cost of machine tools.

关键词： machine tool dynamics carbon fiber reinforced polymer composite laminates

Clinical significance of chromosomal abnormalities detected by interphase fluorescence in situ hybridization in newly diagnosed multiple myeloma patients

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Chinese Medical Journal 2011年第19期124卷 2981-2985页

作者： HU yu chen lei SUN Chun-yan SHE Xiao-mei AI Li-sha QIN You Institute of Hematology Union Hospital Tongji Medical CollegeHuazhong University of Science and Technology Wuhan Hubei 430022 China

Background Chromosome 13q14 deletion （del13q14）, chromosome 1q21 gain （amp1q21） and chromosome 17p13 deletion （del17p13） are the most frequent chromosomal aberrations in multiple myeloma （MM）. They play an important role in prognosis. The aim of this study was to investigate the clinical significance of the chromosomal changes in Chinese MM *** Interphase fluorescence in situ hybridization （FISH） on bone marrow （BM） cells was performed in 72 enrolled MM patients. Relationships between chromosomal abnormalities and clinical features, response to therapies and prognosis were *** As a result of interphase FISH, 77.8% （56/72） patients had chromosome changes. The incidences of each probe were RB1 51.4% （37/72）, D13S319 47.2% （34/72）, 1q21 45.8% （33/72） and p53 22.2% （12/72）. Osteolytic lesion,BM plasma cells index, serum calcium and serum M component were significantly correlated to del13q14. BM plasma cells and hemoglobin were correlated to amp1q21. Serum lactate dehydrogenase （LDH） was correlated with *** with del13q14 treated with bortezomib had a notably higher overall response rate than the patients treated with traditional chemotherapies （93% vs. 65%, P=0.048）. Patients carrying amp1q21 or/and del17p13 did not achieve satisfactory response to bortezomib. The median progression-free survival （PFS） for patients with amp1q21 was 5 months and patients without amp1q21 got 9-month PFS （P=0.001）. The median PFS for patients with del13q14 was 5 months （vs. 8 months, P=0.026）. The median PFS for patients with del17p13 was 3 months （vs. 8 months, P=0.002）.Patients with β2-microglobulin 〉5.5 mg/L also had a worse outcome, whose median PFS was 5 months （vs. 8 months,P=0.016）.Conclusions The prevalence of chromosomal abnormalities of MM patients was similar in Chinese and Caucasian people. Genetic changes were associated with patients＇ responses to therapies and prognosis.

关键词： multiply myeloma fluorescence in situ hybridization cytogenetics prognosis progression free survival

Trace Element Mobility in Subducted Marble and Associated Eclogite:Constraints from UHP Rocks in the Shuanghe Area,Central-East China

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Journal of Earth Science 2024年第1期35卷 1-15页

作者： Xingao Hou Zhiqiang yu Shefa chen lei Liu Yilin Xiao Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

In order to decipher element mobility in UHP meta-sedimentary rocks in the continental subduction zone,major and trace element compositions are investigated for a continuous profile from a representative UHP region in the Dabie *** the lithologic contact zone,contents of K,Ca,LREE,and LILE exhibit varying degrees of downward trends in both marble and eclogite toward the contact zone,indicating that marble and their associated eclogite can release a large amount of K,Ca,and a small number of LILEs and *** is the main Ti phase in both marble and *** rims around rutile can occasionally be seen in *** of Ti and HFSE exhibit a well-coupled relation among marble and eclogite,indicating that substantial Ti and HFSEs were migrated from eclogite to marble,in accord with the capacity of a melt *** and titanites in marble exhibit a relatively limited variation in Nb/Ta ratios(12.9-16.2),similar to those of titanites in eclogite(14.2-16.7),which demonstrates that rutiles and titanites in marble were sourced from eclogite because of short-distance migrations of Ti and *** to the P-T path and the temperature and pressure conditions of the peak metamorphism reported by previous studies,the eclogite associated with marble may not form supercritical fluids in the subduction zone because of the addition of carbonate minerals.

关键词： UHP metamorphism eclogite marble element migration fluid actions geochemistry