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Suppression of Plasma Bubbles over South America under Weak Geomagnetic Perturbations

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Journal of Geodesy and Geoinformation Science 2023年第4期6卷 48-69页

作者： Xunzhe YIN Dongjie YUE Changzhi ZHAI Yutian CHEN xiaoyun cheng School of Earth Sciences and Engineering Hohai UniversityNanjing 210098China

During a long-term Equatorial Plasma Bubbles(EPBs)occurrence between October 2020 and March 2021,a significant EPB suppression event was identified on November 22 and the observations from multi-instrument have been utilized to investigate this ***-scale Observations of the Limb and Disk(GOLD)satellite observed prominent EPBs between 23:40 UT and 23:55 UT during the long-term occurrence ***,no dark stripes representing EPBs were observed on November 22,and the Equatorial Ionization Anomaly(EIA)structure remained *** Total Electron Content(TEC)maps show that these EPBs appeared in the region between 35°W and 65°W longitudes and the magnitudes of the TEC loss in EPBs regions were about 20 *** for 22 November,the S4 index was consistently greater than 0.6 throughout November,indicating significant ionospheric *** Rate Of TEC Index(ROTI)maps revealed that the spatial extent and intensity of EPBs increased after their suppression,and the EPBs were locally *** swarm electron density measurements indicated that the variation amplitudes of EPBs at 510 km altitude were approximately 3 to 5 times larger than that at 460 km *** impact region of EPBs at 510 km was between 15°S and 20°N latitudes,while at 460 km,it was between 0°and 17°N *** the period of EPB suppression,the average h’f at three ionosonde stations decreased by about 50 km,and the vertical drift velocity(V z)approached~0 m/s while it was more than 20 m/s during the long-term occurrence.

关键词： plasma bubble ionospheric scintillation weak geomagnetic perturbations

Analysis of Anomalous Enhancement in TEC and Electron Density in the China Region Prior to the 17 March 2015 Geomagnetic Storm Based on Ground and Space Observations

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Journal of Geodesy and Geoinformation Science 2023年第2期6卷 40-50页

作者： xiaoyun cheng Dongjie YUE Changzhi ZHAI Yutian CHEN Xunzhe YIN School of Earth Sciences and Engineering Hohai UniversityNanjing 211100China

Total Electron Content(TEC)and electron density enhancement were observed on the day before 17 March 2015 great storm in the China *** from ground-and space-based instruments are used to investigate the temporal and spatial evolution of the pre-storm *** enhancement was observed from 24°N to 30°N after 10:00 UT at 105°E,110°E and 115°E longitudes on March *** maximum magnitude of TEC enhancement was more than 10 TECU and the maximal relative TEC enhancement exceeded 30%.Compared with geomagnetic quiet days,the electron density of Equatorial Ionization Anomaly(EIA)northern peak from Swarm A/C satellites on March 16 was larger and at higher ***2 enhanced during 11:30—21:00 UT at Shaoyang Station and increased by 200%at~16:00 ***,TEC and electron density enhancement were not accompanied by a significant change of *** research has excluded some potential mechanisms as the main driving factors for storm-time density enhancements by establishing observational *** this paper,we observed pre-storm enhancement in electron density at different altitudes and Equatorial Electrojet(EEJ)strength results derived from ground magnetometers observations suggest an enhanced eastward electric field from the E region probably played a significant role in this event.

关键词： Equatorial Ionization Anomaly(EIA) electron density geomagnetic storm Total Electron Content(TEC) zonal electric field

Deductive Systems in Hyper EQ-Algebras

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Journal of Mathematical Research with Applications 2017年第2期37卷 183-193页

作者： xiaoyun cheng Xiaolong XIN Yongwei YANG School of Mathematics Northwest University General Education Center Xi'an Peihua University School of Mathematics and Statistics Anyang Normal University

In this paper, we introduce and investigate some types of deductive systems in hyper EQ-algebras and discuss relationships among them. Especially, we focus on investigating two types of important deductive systems, namely,(positive) implicative strong deductive systems, respectively. Moreover we give equivalent characterizations of them.

关键词： hyper EQ-algebra (strong) deductive system (positive) implicative strong deductive system S→-reflexive subset S-semiclosed subset

Research and applications of artificial neural network in pavement engineering:A state-of-the-art review

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第6期8卷 1000-1021页

作者： Xu Yang Jinchao Guan Ling Ding Zhanping You Vincent C.S.Lee Mohd Rosli Mohd Hasan xiaoyun cheng School of Highway Chang'an UniversityXi'an 710064China School of Future Transportation Chang'an UniversityXi'an 710064China College of Transportation Engineering Chang'an UniversityXi'an 710064China Department of Civil and Environmental Engineering Michigan Technological UniversityHoughtonMI 49931USA Faculty of Information Technology Monash UniversityClaytonVIC 3800Australia School of Civil Engineering Universiti Sains MalaysiaNibong Tebal 14300Pulau PinangMalaysia

Given the great advancements in soft computing and data science,artificial neural network(ANN)has been explored and applied to handle complicated problems in the field of pavement *** study conducted a state-of-the-art review for surveying the recent progress of ANN application at different stages of pavement engineering,including pavement design,construction,inspection and monitoring,and *** study focused on the papers published over the last three decades,especially the studies conducted since *** literature retrieval,a total of 683 papers in this field were identified,among which 143 papers were selected for an in-depth *** ANN architectures used in these studies mainly included multi-layer perceptron neural network(MLPNN),convolutional neural network(CNN)and recurrent neural network(RNN)for processing one-dimensional data,two-dimensional data and time-series ***-based pavement health inspection and monitoring attracted the largest research interest due to its potential to replace human *** ANN has been proved to be an effective tool for pavement material design,cost analysis,defect detection and maintenance planning,it is facing huge challenges in terms of data collection,parameter optimization,model transferability and low-cost data *** attention should be paid to bring multidisciplinary techniques into pavement engineering to tackle existing challenges and widen future opportunities.

关键词： Pavement engineering Pavement design Artificial neural network Deep learning Pavement life cycle Health inspection and monitoring

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职住分布与轨道交通网络的耦合效应分析

哈尔滨工业大学学报 2022年第9期54卷 35-43页

作者：程小云张学宇施澄刘钰倩丁玲长安大学运输工程学院西安710064 生态安全屏障区交通网设施管控及循环修复技术交通运输行业重点实验室(长安大学) 西安710064 同济大学建筑与城市规划学院上海200092

为促进城市轨道交通网络与城市空间结构在功能上的协同发展,基于多源数据利用空间联立方程解析职住空间结构形态与轨道交通网络的空间交互关系。采用职住自足性指数测度职住平衡,并提出基于实际路网改进的高斯两步移动搜索(2SFCA)法计... 详细信息

为促进城市轨道交通网络与城市空间结构在功能上的协同发展,基于多源数据利用空间联立方程解析职住空间结构形态与轨道交通网络的空间交互关系。采用职住自足性指数测度职住平衡,并提出基于实际路网改进的高斯两步移动搜索(2SFCA)法计算轨道交通可达性;利用空间联立方程揭示了职住平衡与轨道交通可达性的空间交互效应;引入局部空间自相关探讨了西安市职住空间和轨道交通网络的耦合关系。结果表明:基于实际路网距离的高斯2SFCA法能够更合理地评价轨道交通可达性;区域职住平衡和轨道交通可达性存在互馈作用;两者自身均存在正向空间溢出效应,且两者之间存在正向交互空间溢出效应;从局部耦合效应来看,强化西安市主城区北部和西南部的轨道交通规划与建设,通过城市轨道交通对城市发展的引导作用,优化城市空间结构。研究结果揭示了城市轨道交通网络与职住空间交互作用的规律,可发挥城市轨道交通对优化城市空间布局的合理引导。

关键词：城市交通职住平衡可达性高斯两步移动搜索法空间联立方程耦合效应

生物制剂和小分子药物在炎症性肠病中的应用现状

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中华内科杂志 2021年第4期60卷 376-379页

作者：程小韵李景南中国医学科学院北京协和医学院北京协和医院消化内科100730

炎症性肠病(IBD)发病机制复杂,生物制剂和小分子药物的出现开创了自身免疫相关疾病治疗的新纪元。了解不同药物的作用机制、临床疗效及安全性,有助于临床医师制定最佳的治疗方案,为未来IBD新型治疗模式的开展提供依据。

关键词：炎性肠疾病生物制剂小分子药物

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美国STEM研究生职业技能发展项目实践

学位与研究生教育 2021年第7期 86-93页

作者：肖新祥程小耘湖南师范大学校长办公室湖南师范大学教育科学学院长沙410081

缘于STEM研究生非学术职业领域就业的趋势明显上升,以及其能力素养与雇主所需能力之间的错位,美国研究生院理事会和高校积极探索STEM研究生职业技能培养改革。基于研究生院理事会发布的《为STEM研究生制定有效的职业发展项目》报告,梳... 详细信息

缘于STEM研究生非学术职业领域就业的趋势明显上升,以及其能力素养与雇主所需能力之间的错位,美国研究生院理事会和高校积极探索STEM研究生职业技能培养改革。基于研究生院理事会发布的《为STEM研究生制定有效的职业发展项目》报告,梳理了以职业技能发展项目为抓手的STEM研究生职业技能培养改革,分析职业技能发展项目的改革动向和具体实践,总结实施研究生职业技能发展项目的经验与启示。

关键词： STEM研究生职业技能职业发展研究生教育

IASB/FASB概念框架联合项目中的资产概念研究述评

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会计研究 2010年第5期 25-29页

作者：成小云任咏川西北工业大学会计学院 710072 中央财经大学会计学院 100081

IASB/FASB概念框架联合项目认为,双方现存的资产定义存在"可能的"、"预期的"和"控制"指代不明,以及过分强调"未来经济利益"与"过去交易或事项"等方面的缺陷,提出了新的资产定义。这个新定义强调资产是主体具有排他权利的现时经济资源,... 详细信息

IASB/FASB概念框架联合项目认为,双方现存的资产定义存在"可能的"、"预期的"和"控制"指代不明,以及过分强调"未来经济利益"与"过去交易或事项"等方面的缺陷,提出了新的资产定义。这个新定义强调资产是主体具有排他权利的现时经济资源,摒弃了传统的资产成本观、未来经济利益观和权利观,发展和完善了IASB的资产经济资源观,为建立逻辑一致的概念框架奠定了基础,是对资产本质的科学认识,并与经济学的资产概念保持了一致,是一个值得期待的定义。

关键词：资产概念框架联合项目概念变迁

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经颈静脉肝内门体分流术后肝性脑病研究进展

中国介入影像与治疗学 2019年第2期16卷 117-120页

作者：程小韵张春清山东大学附属省立医院消化内科山东济南250021

肝性脑病(HE)可引起不同程度的神经精神异常。经颈静脉肝内门体分流术(TIPS)术后高发HE,严重制约其在门静脉高压症治疗中的应用。本文主要对TIPS术后HE的发病机制、危险因素和治疗方面的研究进展进行综述。

关键词：肝性脑病门体分流术,经颈静脉肝内支架