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PPP-RTK修正产品矢量化完好性监测方法

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测绘学报 2024年第9期53卷 1777-1789页

作者：李亮王柳淇王宁波李敏李子申杜丰泽庞帅那志博哈尔滨工程大学智能科学与工程学院黑龙江哈尔滨150001 中国科学院空天信息创新研究院北京100094 齐鲁空天信息创新研究院山东济南250132

PPP-RTK修正产品是实现卫星导航高精度、快收敛精密定位的基础信息,完好性监测是保障PPP-RTK导航定位可靠性的核心关键。传统PPP-RTK修正产品完好性监测方法存在风险概率分配体系不完善及多重风险源监测灵敏度不足的问题,导致PPP-RTK修... 详细信息

PPP-RTK修正产品是实现卫星导航高精度、快收敛精密定位的基础信息,完好性监测是保障PPP-RTK导航定位可靠性的核心关键。传统PPP-RTK修正产品完好性监测方法存在风险概率分配体系不完善及多重风险源监测灵敏度不足的问题,导致PPP-RTK修正产品的可用性较低。针对此,本文提出了PPP-RTK修正产品矢量化完好性监测方法,基于最优保护水平准则分配PPP-RTK修正产品完好性与连续性指标,设计PPP-RTK修正产品“播发前-播发后”测距域与定位域协同的序贯监测架构,形成面向载波相位层级的矢量分类监测与多站综合监测,实现PPP-RTK修正产品高灵敏、高可用的矢量化完好性监测。仿真与实测数据的分析结果表明,PPP-RTK修正产品矢量化完好性监测方法监测灵敏度与可用性均优于传统方法,可用性可达到99%以上。

关键词： PPP-RTK 修正产品完好性监测矢量化可用性

Intelligent fault diagnosis methods toward gas turbine: A review

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Chinese Journal of Aeronautics 2024年第4期37卷 93-120页

作者： Xiaofeng LIU Yingjie CHEN liuqi XIONG Jianhua wang Chenshuang LUO Liming ZHANG Kehuan wang School of Transportation Science and Engineering Beihang UniversityBeijing 100191China Systems Engineering Research Institute China State Shipbuilding CorporationBeijing 100094China

Fault diagnosis plays a significant role in conducting condition-based maintenance and health management for gas turbines(GTs) to improve reliability and reduce costs. Various diagnosis methods developed by modeling engine systems or certain components implement faults detection and diagnosis based on the measurement of systemic parameters deviations. However, these conventional model-based methods are hindered by limitations of inability to handle the nonlinear nature, measurement uncertainty, fault coupling and other implementing problems. Recently, the development of artificial intelligence algorithms has provided an effective solution to the above problems, triggering broad researches for data-driven fault diagnosis methods with better accuracy,dynamic performance, and universality. This paper presents a systematic review of recently proposed intelligent fault diagnosis methods for GT engines, according to the classification of shallow learning methods, deep learning methods and hybrid intelligent methods. Moreover, the principle of typical algorithms, the evolution of enhanced methods, and the assessment of pros and cons are summarized to conclude the present status and look forward to the future in the field of GT fault diagnosis. Possible directions for development in method validation, information fusion, and interpretability of intelligent diagnosis methods are concluded in the end to provide insightful concepts for scholars in related fields.

关键词： Fault diagnosis Health management Gas turbine Artificial intelligence Intelligent diagnosis method

3D-bioprinted anisotropic bicellular living hydrogels boost osteochondral regeneration via reconstruction of cartilage–bone interface

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The Innovation 2024年第2期5卷 88-97页

作者： Yijian Zhang Duo Li Yang Liu liuqi Peng Dongdong Lu Pinpin wang Dongxu Ke Huilin Yang Xuesong Zhu Changshun Ruan Department of Orthopaedics The First Affiliated Hospital of Soochow UniversitySoochow UniversitySuzhou 215006China Research Center for Human Tissue and Organ Degeneration Institute of Biomedicine and BiotechnologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China University of Chinese Academy of Sciences Beijing 100049China Novaprint Therapeutics Suzhou Co. Ltd.Room 605B1 BuildingBioBayNo.218 Xinghu StreetSuzhou Industrial ParkSuzhou 215000China

Reconstruction of osteochondral(OC)defects represents an immense challenge due to the need for synchronous regeneration of special stratified *** revolutionary innovation of bioprinting provides a robust method for precise fabrication of tissue-engineered OCs with hierarchical structure;however,their spatial living cues for simultaneous fulfilment of osteogenesis and chondrogenesis to reconstruct the cartilage-bone interface of OC are ***,inspired by natural OC bilayer features,anisotropic bicellular living hydrogels(ABLHs)simultaneously embedding articular cartilage progenitor cells(ACPCs)and bone mesenchymal stem cells(BMSCs)in stratified layers were precisely fabricated via two-channel extrusion *** optimum formulation of the 7%GelMA/3%AlgMA hydrogel bioink was demonstrated,with excellent printability at room temperature and maintained high cell ***,the chondrogenic ability of ACPCs and the osteogenic ability of BMSCs were demonstrated in vitro,confirming the inherent differential spatial regulation of ABLHs.

关键词： printing stratified boost

LEO Spaceborne Receiver Autonomous Integrity Monitoring Algorithm Based On Dynamic Model Assistance

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LEO Spaceborne Receiver Autonomous Integrity Monitoring Algo...

Lake Sequence Stratigraphy of the Shahejie Formation in the Zhanhua Hollow, Shandong Province

第十三届中国卫星导航年会

作者： Chuanpeng Guo Ruijie Li liuqi wang Yi Liu Qiwei Ye Harbin Engineering University

Spaceborne terminal receiver autonomous integrity monitoring can trigger alarm information to users in time when the orbit determination error of a Low Earth Orbit（LEO） satellite exceeds the allowable limit. It is indispensable for the application of LEO satellites in navigation services that involve life safety. The traditional Receiver Autonomous Integrity Monitoring（RAIM） based on the least square residual snapshot is implemented in the measurement domain. It fails to make full use of good dynamic characteristics of LEO satellites, resulting in relatively low availability. This paper proposes an RAIM for LEO satellite receivers based on dynamic model assistance. This method is based on the extended kalman filter and integrates the observation model and dynamic model of LEO satellites, then respectively construct test statistic and protection level. In this paper, RAIM based on least square residuals is used as a contrast, and simulation is designed to verify the performance of the proposed algorithm. Simulation results show that the fault detection ability is improved by introducing the dynamic model of the LEO satellite. At the same time, the availability of the proposed method is tested at 10, 20 and 50 meters, and the results show that the availability of the proposed method is improved by 98.84%, 93.28% and 37.84%.

关键词： Integrity Monitoring Low Earth Orbit Satellite Dynamic Model Extended Kalman Filter

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Acta Geologica Sinica(English Edition) 1997年第1期71卷 104-114页

作者： wang liuqi Jiang Zaixing Cao Yingchang Han Wentao and Wu Jing University of Petroleum, Dongying Shandong Shengli Oil Field, Dongying Shandong Fei Zhenbi and Shi Xiaoying University of Petroleum Dongying Shandong Shengli Oil Field Dongying Shandong [?]wang liuqi Born in 1965 received his master degree from University of Petroleum in 1990 now Lecturer at the Department of Exploration University of Petroleum especially interested in the study of sedimentology and sequence stratigraphy.

Two sequences can be identified in the sedimentary strata of the lower Tertiary ShahejieFormation in the Zhanhua hollow. The lowstand, lake-transgressive and highstand systemstracts were formed under the control of ancient structure, palaeotopography, palaeoclimate, sed-iment supply, marine-transgression, and so on. In the paper the authors present a composite se-quence stratigraphical section of the Shahejie Formation in this area, and expound the bounda-ries of parasequences, parasequences set and systems tracts and evolutions of lake sequencestratigraphy and sedimentology and discuss various factors controlling the lake level *** differences between lake and marine sequence stratigraphy are also indicated in the *** lake sequence stratigraphical study should be based on a synthetic analysis of structural evo-lution, palaeomagnetism, palaeoclimatic changes, geological Well logs, seismic and logging data,palaeontological data, global sea level changes, and so on. The sequence stratigraphical evolutionis closely related to the formation, development and elimination of the whole basin and thesedimentary process.

关键词： lake sequence stratigraphy sedimentology lake level fluctuation whole basin Shahejie Formation Zhanhua hollow, Shandong province

含内热源多孔介质-自由流通道内非达西强制对流

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工程热物理学报 2023年第6期44卷 1631-1641页

作者：李琪郭蕊王柳淇胡鹏飞东北电力大学能源与动力工程学院吉林132012

基于多孔介质局部非热平衡模型,对考虑内热源条件下的多孔介质-自由流耦合通道内非达西对流换热特性进行研究。多孔介质区内流体运动方程采用Darcy-Brinkman-Forchheimer模型,利用有限差分法获得通道内各区域流体运动速度、流固相温度... 详细信息

基于多孔介质局部非热平衡模型,对考虑内热源条件下的多孔介质-自由流耦合通道内非达西对流换热特性进行研究。多孔介质区内流体运动方程采用Darcy-Brinkman-Forchheimer模型,利用有限差分法获得通道内各区域流体运动速度、流固相温度分布及努塞尔数,并进一步分析了相关参数对流体流动传热的影响。结果表明:在文中研究参数下,惯性参数F_(f)对通道内各区域流体速度及温度分布的影响仅在达西数Da大于10^(-3)时需要考虑;增加F_(f)或降低固相内热源W_(s)绝对值会使流固两相温差减小,且改变固相内热源换热方向会使多孔介质区内流固相发生温度分岔现象;固相内热源对通道换热效果影响较大且更为复杂,不同惯性参数F_(f)下,考虑W_(s)时可能会使Nu出现奇异点。

关键词：多孔介质自由流内热源非达西强制对流

^(18)F-prostate specific membrane antigen positron emission tomography/computerized tomography for lymph node staging in medium/high risk prostate cancer:A systematic review and meta-analysis

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Chinese Medical Journal 2024年第8期137卷 949-958页

作者： Zhengtong Lv liuqi Song Miao wang Huimin Hou Haodong Li Xuan wang Jianye wang Jianlong wang Ming Liu Department of Urology Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China Graduate School of Peking Union Medical College and Chinese Academy of Medical Sciences Beijing 100730China Peking University Fifth School of Clinical Medicine Beijing 100730China Peking University China-Japan Friendship School of Clinical Medicine Beijing 100029China

Background:Lymph node staging of prostate cancer(PCa)is important for planning and monitoring of treatment.^(18)F-prostate specific membrane antigen positron emission tomography/computerized tomography(^(18)F-PSMA PET/CT)has several advantages over^(68)Ga-PSMA PET/CT,but its diagnostic value requires further *** meta-analysis focused on establishing the diagnostic utility of^(18)F-PSMA PET/CT for lymph node staging in medium/high-risk ***:We searched the EMBASE,PubMed,Cochrane library,and Web of Science databases from inception to October 1,*** cancer,^(18)F,lymph node,PSMA,and PET/CT were used as search terms and the language was limited to *** additionally performed a manual search using the reference lists of key *** and study characteristics were extracted and the QUADAS-2 tool was employed to evaluate the quality of included ***,specificity,the positive and negative likelihood ratio(PLR and NLR),diagnostic odds ratio(DOR),area under the curve(AUC),and 95%confidence interval(CI)were used to evaluate the diagnostic value of^(18)F-PSMA PET/*** 17 software was employed for calculation and statistical ***:A total of eight diagnostic tests including 734 individual samples and 6346 lymph nodes were included in this *** the patient level,the results of each consolidated summary were as follows:sensitivity of 0.57(95%CI 0.39-0.73),specificity of 0.95(95%CI 0.92-0.97),PLR of 11.2(95%CI 6.6-19.0),NLR of 0.46(95%CI 0.31-0.68),DOR of 25(95%CI 11-54),and AUC of 0.94(95%CI 0.92-0.96).At the lesion level,the results of each consolidated summary were as follows:sensitivity of 0.40(95%CI 0.21-0.62),specificity of 0.99(95%CI 0.95-1.00),PLR of 40.0(95%CI 9.1-176.3),NLR of 0.61(95%CI 0.42-0.87),DOR of 66(95%CI 14-311),and AUC of 0.86(95%CI 0.83-0.89).Conclusions:^(18)F-PSMA PET/CT showed moderate sensitivity but high specificity in lymph node staging of medium/high-risk *** diag

关键词： ^(18)F-PSMA PET/CT Diagnostic test Lymph node Meta-analysis Prostate cancer

SEQUENCE　STRATIGRAPHIC　MODELS　FOR　A　RIFT　LACUSTRINE　BASIN－AN　EXAMPLE　FROM　THE　JIYANG　DEPRESSION　IN　THE　BOHAI　BAY　BASIN

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Scientia Geologica Sinica 1995年第4期 467-474页

作者： Cao Yingchang Jiang Zaixing wang liuqi Qian Zheng Zhang Wanchun and Ma Yuxin (University of Petroleum, Dongying, Shandong 257062)

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关键词：

汉语特色块状语英译认知研究——时政文本视域下的翻译能力调查

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外语教学理论与实践 2021年第4期 137-145,F0004页

作者：刘绍龙王惠王柳琪浙江越秀外国语学院西交利物浦大学人文社科学院

在语言加工双通道论观照下,研究者通过纵向实证方法探究时政文本视域下三种水平译者之块状语表征心理现实性、认知加工范式、转换策略等差异对多字格块状语英译的影响。结果发现:1.就低、中水平学生译者而言,六字格块状语翻译质量最低,... 详细信息

在语言加工双通道论观照下,研究者通过纵向实证方法探究时政文本视域下三种水平译者之块状语表征心理现实性、认知加工范式、转换策略等差异对多字格块状语英译的影响。结果发现:1.就低、中水平学生译者而言,六字格块状语翻译质量最低,其次是三字格块状语;2.四字格块状语的翻译质量相对较高,且组间差异也更大;3.从译者水平由低至高的路径来看,不同字格数块状语英译的加工范式呈现出分析性加工范式至整体性加工范式的连续体发展模式;4.学生译者策略多以异化和直译/硬译为主,专家译者归化、意译策略凸显且稳定。据此,本文得到两点重要启示:学生译者的双语关联块状语表征亟待完善,翻译加工范式及策略的使用偏好有待调控和改进。

关键词：汉语特色块状语关联块构表征加工范式/策略