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A two-stage optimization method for unmanned aerial vehicle inspection of an oil and gas pipeline network

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Petroleum Science 2019年第2期16卷 458-468页

作者： Yamin Yan Yongtu Liang Haoran Zhang Wan Zhang Huixia Feng Bohong Wang qi liao Beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum-Beijing

Oil and gas pipeline networks are a key link in the coordinated development of oil and gas both upstream and *** improve the reliability and safety of the oil and gas pipeline network, inspections are implemented to minimize the risk of leakage, spill and theft, as well as documenting actual incidents. In recent years, unmanned aerial vehicles have been recognized as a promising option for inspection due to their high efficiency. However, the integrated optimization of unmanned aerial vehicle inspection for oil and gas pipeline networks, including physical feasibility, the performance of mission, cooperation, real-time implementation and three-dimensional(3-D) space, is a strategic problem due to its large-scale,complexity as well as the need for efficiency. In this work, a novel mixed-integer nonlinear programming model is proposed that takes into account the constraints of the mission scenario and the safety performance of unmanned aerial vehicles. To minimize the total length of the inspection path, the model is solved by a two-stage solution method. Finally, a virtual pipeline network and a practical pipeline network are set as two examples to demonstrate the performance of the optimization schemes. Moreover, compared with the traditional genetic algorithm and simulated annealing algorithm, the self-adaptive genetic simulated annealing algorithm proposed in this paper provides strong stability.

关键词： Pipeline network Unmanned aerial vehicle inspection Mixed-integer nonlinear programming Two-stage solution

Ginkgolide C Stimulates CFTR-mediate Anion Conductance in Distal Colon:Implication for Therapy of Gastrointestinal Diseases

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Chemical Research in Chinese Universities 2009年第6期25卷 909-913页

作者： liao qi MA Xiao-yan WU Fu-ju YANG Li-xiao WANG Shuai Second Teaching Hospital of Jilin University Changchun 130041 P. R. China The Daqing Longnan Hospital Daqing 163453 P. R. China

The effects and the mechanisms of natural compounds ginkgolides on CFTR-mediate anion transport were investigated. The CFTR-mediate iodide influx rates were studied via a cell-based fluorescence assay done for FRT cells stably transfected by CFTR; transepithelial short-circuit current recordings of FRT cells and rat distal colon mucosa were respectively obtained. Cellular cAMP concentrations were measured via a radioimmunoassay analysis kit. Ginkgolide C dose-dependently increases CFTR-mediate anion transport, whereas ginkgolide A and B show no effect. The activation is sensitive to CFTR specific activator CFTRinh-172. Ginkgolide C stimulated amiloride and indomethacin pre-treated Cl currents in rat distal colon mucosa. Studies on FRT cells also manifest that ginkgolide C had additive effect with FSK/IBMX mixture and didn＇t elevate intracellular cAMP concentration, which implies it works through a direct binding mechanism. In conclusion, Ginkgolide C directly stimulates CFTR-mediate anion transport. Ginkgolide C may be a promising drug for the prevention and treatment of CFTR-related diseases such as idiopathic chronic pancreatitis（ICP）, habitual constipation, and kcratoconjunctivitis sicca（KCS）.

关键词： Ginkgolide Cystic fibrosis transmembrane conductance regulator Fluorescence Mucosa

汨罗市白塘镇-桃林寺镇土壤镉元素分布特征及成因分析

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四川地质学报 2024年第2期44卷 294-298,305页

作者：廖琦肖粤新杨鹏至卢欣毛雄中国地质调查局长沙自然资源综合调查中心长沙410000

针对汨罗市白塘镇-桃林寺镇土壤镉污染情况,基于网格布点法系统采集1:5万表层土壤和垂向剖面土壤样品,对土壤的As、Cd、Pb、Cu、Zn、Ni、Cr、Hg元素含量及pH进行测定,采取统计学与GIS相结合的方法重点研究镉元素空间分布特征及其变化规... 详细信息

针对汨罗市白塘镇-桃林寺镇土壤镉污染情况,基于网格布点法系统采集1:5万表层土壤和垂向剖面土壤样品,对土壤的As、Cd、Pb、Cu、Zn、Ni、Cr、Hg元素含量及pH进行测定,采取统计学与GIS相结合的方法重点研究镉元素空间分布特征及其变化规律与异常成因。结果表明:区内表层土壤镉元素平均浓度为0.25 mg/kg,变化幅度为0.03~2.55 mg/kg,高于全国背景值,但低于洞庭-江汉平原土壤背景值;研究区表层土壤镉分布特点受土壤p H值、土地利用类型、成土母质影响,且在表层土壤明显富集;垂向剖面指示了研究区西北一带深层土壤还受到湘江重金属污染影响。通过PCA主成分分析表明,区内土壤镉元素主要来源于湘江搬运而来的物质经农田灌溉进入土壤,其次是大气干湿沉降物和成土母质。研究结果可以为研究区农田土壤重金属污染防控对策制定提供科学依据。

关键词：土壤镉地球化学特征

广东省县级国土空间总体规划成果质检软件设计与实现

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地理空间信息 2024年第1期22卷 109-113页

作者：周艺霖韩赓廖琪曹凤丽向强广东省土地调查规划院广东广州510075 自然资源部陆表系统与人地关系重点实验室广东广州510075 吉奥时空信息技术股份有限公司湖北武汉430223

基于C/S架构,运用空间数据分布式质检技术、质检规则耗时等级评估技术、质检规则检查容错重试机制、海量异构数据版本化管理技术、业务流程自动化技术等完成了定制化县级国土空间总体规划数据库质检软件的开发,实现了县级国土空间总体... 详细信息

基于C/S架构,运用空间数据分布式质检技术、质检规则耗时等级评估技术、质检规则检查容错重试机制、海量异构数据版本化管理技术、业务流程自动化技术等完成了定制化县级国土空间总体规划数据库质检软件的开发,实现了县级国土空间总体规划数据库的检查、入库、汇交和分析全流程管理。分布式质检方法大大提高了质检工作效率,确保了广东省124个县级国土空间总体规划数据库的完整性、规范性和业务符合性,保障了县级国土空间总体规划数据库成果审查工作高效率、高质量运行。

关键词：国土空间总体规划分布式数据库质检软件广东省县级

Synergistic Effects of Chuanxiong-Chishao Herb-Pair on Promoting Angiogenesis at Network Pharmacological and Pharmacodynamic Levels

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Chinese Journal of Integrative Medicine 2017年第9期23卷 654-662页

作者： WANG Yan GUO Gang YANG Bin-rui XIN qi-qi liao qi-wen LEE Simon Ming-Yuen HU Yuan-jia CHEN Ke-ji CONG Wei-hong Clinical Medical College Beijing University of Chinese Medicine Laboratory of Cardiovascular Diseases Xiyuan Hospital China Academy of Chinese Medical Sciences State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical Sciences University of Macao Department of Acupuncture and Moxibustion Qilu Hospital Affiliated to Shandong University

Objective： To investigate the synergistic effects of Chuanxiong-Chishao herb-pair （CCHP） on promoting angiogenesis in silico and in vivo. Methods： The mechanisms of action of an herb-pair, Chuanxiong- Chishao, were investigated using the network pharmacological and pharmacodynamic strategies involving computational drug target prediction and network analysis, and experimental validation. A set of network pharmacology methods were created to study the herbs in the context of targets and diseases networks, including prediction of target profiles and pharmacological actions of main active compounds in Chuanxiong and Chishao. Furthermore, the therapeutic effects and putative molecular mechanisms of Chuanxiong-Chishao actions were experimentally validated in a chemical-induced vascular insufficiency model of transgenic zebrafish in vivo. The mRNA expression of the predicted targets were further analyzed by real-time polymerase chain reaction （RT-PCR）. Results： The computational prediction results found that the compounds in Chuanxiong have antithrombotic, antihypertensive, antiarrhythmic, and antiatherosclerotic activities, which were closely related to protecting against hypoxic-ischemic encephalopathy, ischemic stroke, myocardial infarction and heart failure. In addition, compounds in Chishao were found to participate in anti-inflammatory effect and analgesics. Particularly, estrogen receptor α （ESR α） and hypoxia-inducible factor 1-α （HIF-1 α） were the most important potential protein targets in the predicted results. In vivo experimental validation showed that post-treatment of tetramethylpyrazine hydrochloride （TMpoHCI） and paeoniflorin （PF） promoted the regeneration of new blood vessels in zebrafish involving up-regulating ESR α mRNA expression. Co-treatment of TMP·HCI and PF could enhance the vessel sprouting in chemical-induced vascular insufficiency zebrafish at the optimal compatibility proportion of PF 10 μ mol/L with TMP·HCI 1 μ mol/L. Conclusions： The networ

关键词： tetramethylpyrazine paeoniflorin,angiogenesis network pharmacology

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成品油管网批次在线跟踪技术

油气与新能源 2024年第4期36卷 67-75页

作者：杜渐郑坚钦赵伟廖绮李苗梁永图中国石油大学(北京)油气管道输送安全国家工程实验室/石油工程教育部重点实验室/城市油气输配技术北京市重点实验室北京102249 中国石油天然气股份有限公司规划总院北京100083 国家管网集团工程技术创新有限公司天津120118 国家石油天然气管网集团有限公司华南分公司广州510623

成品油管网批次界面跟踪系统可基于实时运行数据实现管内批次位置实时跟踪、到站时间预测等,进而辅助站场精确掌握批次分输及混油下载时间,对于防止油品质量事故、提高站场管理效率具有重要意义。但现有批次跟踪方法基于体积推移算法,... 详细信息

成品油管网批次界面跟踪系统可基于实时运行数据实现管内批次位置实时跟踪、到站时间预测等,进而辅助站场精确掌握批次分输及混油下载时间,对于防止油品质量事故、提高站场管理效率具有重要意义。但现有批次跟踪方法基于体积推移算法,易受管内水力热力变化干扰,模型误差较大。提取管网实时流量密度数据,根据密度、阀门状态变化动态识别到站批次,并启动下游管道批次计算;基于油品体积流入、流出守恒定律构建批次界面推移计算模型,并考虑了由于混油、温度压力影响导致的油品体积动态变化,修正批次跟踪模型以补偿体积动态变化造成的批次位置偏差,最终开发了成品油管网批次界面实时跟踪系统。利用某成品油管网历史运行数据进行测试,结果表明,不考虑偏差修正的批次跟踪结果与实际到站时间的平均误差为10.87 min,而考虑温度压力修正模型的平均误差仅为3.8 min,误差降低了65%。该系统可满足管道运行管理的生产需求,有助于提高批次界面跟踪的工作效率,防止油品质量事故。

关键词：成品油管网批次界面跟踪体积推移修正模型

耦合混油发展机理与数据修正的成品油管道混油浓度预测

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油气储运 2024年第7期43卷 796-808页

作者：杜渐郑坚钦夏玉恒张秀玲徐宁廖绮涂仁福梁永图中国石油大学(北京)油气管道输送安全国家工程研究中心·石油工程教育部重点实验室·城市油气输配技术北京市重点实验室中国石油规划总院中国石油大学(北京)克拉玛依校区工学院

【目的】顺序输送成品油管道不可避免会在相邻油品交界处产生混油段,影响站场调度计划与分输方案制定,准确预测混油段浓度分布是提高站场混油控制水平、降低混油处理能耗、防止油品质量事故的重要依据。然而,多维混油数值模型计算时间... 详细信息

【目的】顺序输送成品油管道不可避免会在相邻油品交界处产生混油段,影响站场调度计划与分输方案制定,准确预测混油段浓度分布是提高站场混油控制水平、降低混油处理能耗、防止油品质量事故的重要依据。然而,多维混油数值模型计算时间过长、难以应用于长输管道,传统数据驱动方法忽略混油发展机理过程,结果可能违背物理原理,准确度及可解释性差。【方法】通过分析混油发展机理,深入挖掘混油发展遵循的基本控制方程与初始边界条件,通过自动微分方式与深度学习模型耦合以构造物理指导的耦合损失函数,将模型预测结果约束至混油发展所对应的物理解空间内;再利用短管道初始数值解,基于管道递推滚动预测与数据修正方法,预测长输管道混油浓度分布。【结果】数值案例表明,所建模型相较传统数据驱动方法准确度更高,MAPE降低了91%,对数据依赖程度更低,RMSE波动程度随数据量变化降低了60%;相较Fluent数值仿真方法,计算成本降低至原先的12%;现场工程化应用实例表明,相较Taylor模型与改进Taylor模型,所提出的工程化应用框架的MAE分别降低了71%、58%,可实现长输管道混油浓度分布高效求解。【结论】耦合混油发展机理与数据修正的成品油管道混油浓度预测方法可准确快速预测长输管道混油浓度分布,指导站场混油接收方案制定,有效提高混油控制智能化水平。

关键词：成品油管道混油浓度预测物理信息神经网络基本控制方程滚动预测

Spatial Variability of Soil Organic Carbon and Related Factors in Jiangsu Province,China

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Pedosphere 2012年第3期22卷 404-414页

作者： CHUAI Xiao-Wei HUANG Xian-Jin WANG Wan-Jing ZHANG Mei LAI Li liao qi-Lin School of Geographic&Oceanographic Sciences Nanjing UniversityNanjing 210093(China) Land Development and Consolidation Technology Engineering Center of Jiangsu Province Nanjing 210093(China) Department of Urban and Resource Sciences Jinling CollegeNanjing UniversityNanjing 210093(China) jiangsu information Center Nanjing 210013(China) Geological Survey of Jiangsu Province Nanjing 210018(China)

Soil organic carbon (SOC) plays a key role in the global carbon *** this study,we used statistical and geostatistical methods to characterize and compare the spatial heterogeneity of SOC in soils of Jiangsu Province,China,and investigate the factors that influence it,such as topography,soil type,and land *** study was based on 24 186 soil samples obtained from the surface soil layer (0-0.2 m) and covering the entire area of the *** values of SOC density in the surface layer,obtained by kriging based on a spherical model,ranged between 3.25 and 32.43 kg m *** highest SOC densities tended to occur in the Taihu Plain,Lixia River Plain,along the Yangtze River,and in high-elevation hilly areas such as those in northern and southwest Jiangsu,while the lowest values were found in the coastal ***,slope,soil type,and land use type significantly affected SOC *** slope tended to result in SOC *** between elevation and SOC densities was positive in the hill areas but negative in the low plain areas,probably due to the effect of different land cover types,temperature,and soil *** SOC densities were usually found in limestone and paddy soils and low densities in coastal saline soils and alluvial soils,indicating that high clay and silt contents in the soils could lead to an increase,and high sand content to a decrease in the accumulation of *** densities were sensitive to land use and usually increased in towns,woodland,paddy land,and shallow water areas,which were strongly affected by industrial and human activities,covered with highly productive vegetation,or subject to long-term use of organic fertilizers or flooding conditions.

关键词： industrial and human activities land cover land use soil type topography

OnionGraph:Hierarchical topology+attribute multivariate network visualization

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Visual Informatics 2020年第1期4卷 43-57页

作者： Lei Shi qi liao Hanghang Tong Yifan Hu Chaoli Wang Chuang Lin Weihong qian ACT&BDBC Department of Computer Science&EngineeringBeihang UniversityBeijing 100191China Department of Computer Science Central Michigan UniversityMount PleasantMI 48859United States Department of Computer Science University of Illinois at Urbana-ChampaignChampaignIL 61820United States Yahoo Labs New YorkNY 10036United States Department of Computer Science&Engineering University of Notre DameNotre DameIN 46556United States Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China Alibaba Cloud Beijing 100102China

Hierarchical abstraction is a scalable strategy to deal with large *** visualization methods have allowed to aggregate the network nodes into hierarchies based on the node attributes or network topology,each of which has its own *** few previous system has the capability to enjoy the best of both *** paper presents OnionGraph,an integrated framework for the exploratory visual analysis of heterogeneous multivariate *** allows nodes to be aggregated based on either node attributes,topology,or a hierarchical combination of *** aggregations can be split,merged and filtered under the focus+context interaction model,or automatically traversed by the information-theoretic navigation *** aggregations that contain subsets of nodes are displayed by the onion metaphor,indicating the level and details of the *** have evaluated the OnionGraph tool in three real-world *** experiments demonstrate that on a commodity desktop,our method can scale to million-node networks while preserving the interactivity for analysis.

关键词： Multivariate network visualization Hierarchical abstraction Focus+context Entropy