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Provenance of the Lower Jurassic pyroclastic sediments in the Zigui Basin:Implication for crustal thickening in the eastern Qinling orogenic belt

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Science China Earth Sciences 2024年第1期67卷 196-207页

作者： Rong CHAI Jianghai YANG Yuansheng DU chengshan wang School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100023China School of Earth Sciences China University of Geosciences(Wuhan)Wuhan 430074China Chinese Academy of Geological Sciences Beijing 100037China

The Late Triassic witnessed significant collisional orogenic events in the Qinling orogenic belt,accompanied by magma underplating and tectonic deformation.These processes potentially resulted in substantial crustal thickening and uplift of the Qinling orogen.However,due to the absence of igneous rock records from this period in the eastern section of the Qinling orogen,the changes in crustal thickness during this orogenic process have not been thoroughly investigated.A series of foreland basins emerged during the Early Mesozoic to the south of the East Qinling orogenic belt.These basins have preserved clastic sedimentary rocks derived from the uplift and erosion of the orogenic belt.These sedimentary records serve as crucial records to reconstruct the evolutionary history of the Qinling orogen.To further clarify the collisional orogenic process of the Qinling orogenic belt,this study conducted in situ volcanic lithic fragment geochemistry,detrital zircon U-Pb chronology and trace element composition analysis on the sandstones of the Lower Jurassic Tongzhuyuan Formation in the Zigui Basin.The results suggest that the sandstones,which exhibit a significant abundance of volcanic lithic fragments,has a characteristic detrital zircon age group of 250–200 Ma,indicating a major provenance from the Triassic volcanic rocks.Combined with regional correlation and paleocurrent analysis,the detrital zircon U-Pb age data show that the source area of volcanic rocks should be in the Qinling orogenic belt to the north of the basin.This interpretation is further supported by the Triassic granitic rocks exposed in the western part of the orogenic belt,representing the magmatism during the Triassic collisional orogenesis in the Qinling orogen.Based on the co-varying relationships between present-day crust thickness with the chemical compositions of granite rocks and zircons,the La/Yb ratio of volcanic lithic fragments in the Tongzhuyuan Formation and the Eu/Eu*ratio of detrital zircons with Triassic ages indicate that the Qinling o

关键词： Qinling orogenic belt Zigui Basin Late Triassic Detrital zircons Crustal thickening

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Online identification and extraction method of regional large-scale adjustable load-aggregation characteristics

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Global Energy Interconnection 2024年第3期7卷 313-323页

作者： Siwei Li Liang Yue Xiangyu Kong chengshan wang Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjin 300072P.R.China Beijing Fibrlink Communications Co. Ltd.Beijing 100071P.R.China

This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online identification method is a computer-involved approach for data collection,processing,and system identification,commonly used for adaptive control and prediction.This paper proposes a method for dynamically aggregating large-scale adjustable loads to support high proportions of new energy integration,aiming to study the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction methods.The experiment selected 300 central air conditioners as the research subject and analyzed their regulation characteristics,economic efficiency,and comfort.The experimental results show that as the adjustment time of the air conditioner increases from 5 minutes to 35 minutes,the stable adjustment quantity during the adjustment period decreases from 28.46 to 3.57,indicating that air conditioning loads can be controlled over a long period and have better adjustment effects in the short term.Overall,the experimental results of this paper demonstrate that analyzing the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction algorithms is effective.

关键词： Load aggregation Regional large-scale Online recognition Feature extraction method

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A Mode-switching Strategy of Droop Control for VSC-MTDC Systems Considering Maximum DC Voltage Regulation Capability

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 903-912页

作者： Yizhen wang Fengliang Qiu Zhongguan wang Yirun Ji Zhengguang Chen chengshan wang Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjin 300072China Electric Power Research Institute of State Grid JiBei Electric Power Co.Ltd. Beijing 100045China State Grid Corporation of China Beijing 100031China IEEE

To achieve the goal of carbon neutrality,renewable energy integration through a voltage source converter based multi-terminal direct current(VSC-MTDC)system has been identified as a promising solution.To tackle the significant DC voltage over-limit problem in a VSC-MTDC system during disturbances,this paper proposes a mode-switching strategy of droop control considering maximum DC voltage regulation capability.The close relationship between node injection powers and node DC voltages in the MTDC system is elaborated,and the most effective regulation approach of local injection power for limiting DC voltage deviation is presented.The operating point trajectories of different droop control explains that the DC voltage deviation can be minimized by fully utilizing the capacity of converters.Therefore,the mode-switching strategy with the maximum DC voltage regulation capability is realized by the switching between the voltage droop control and the constant maximum power control.In addition,a mode recovery process and a smooth switching method are developed to make converters regain the capability of maintaining DC voltage and reduce power fluctuation during mode switching,respectively.Furthermore,three cases are investigated to verify the effectiveness of the proposed mode-switching strategy.Compared with simulation results of the conventional droop control and the DC voltage deviation-dependent droop control,better performance of transient and steady-state DC voltage deviation is achieved through the proposed strategy.

关键词： Droop control maximum DC voltage regulation capability mode-switching VSC-MTDC

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An Analytical Method for Delineating Feasible Region for PV Integration Capacities in Net-zero Distribution Systems Considering Battery Energy Storage System Flexibility

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 475-487页

作者： Shida Zhang Shaoyun Ge Hong Liu Guocheng Hou chengshan wang School of Electrical and Information Engineering Tianjin UniversityTianjin 300072China

To provide guidance for photovoltaic(PV)system integration in net-zero distribution systems(DSs),this paper proposes an analytical method for delineating the feasible region for PV integration capacities(PVICs),where the impact of battery energy storage system(BESS)flexibility is considered.First,we introduce distributionally robust chance constraints on network security and energy/carbon net-zero requirements,which form the upper and lower bounds of the feasible region.Then,the formulation and solution of the feasible region is proposed.The resulting analytical expression is a set of linear inequalities,illustrating that the feasible region is a polyhedron in a high-dimensional space.A procedure is designed to verify and adjust the feasible region,ensuring that it satisfies network loss constraints under alternating current(AC)power flow.Case studies on the 4-bus system,the IEEE 33-bus system,and the IEEE 123-bus system verify the effectiveness of the proposed method.It is demonstrated that the proposed method fully captures the spatio-temporal coupling relationship among PVs,loads,and BESSs,while also quantifying the impact of this relationship on the boundaries of the feasible region.

关键词： Net-zero distribution system photovoltaic(PV)integration capacity feasible region battery energy storage system(BESS).

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Pore Connectivity of Deep Lacustrine Shale and its Effect on Gas-bearing Characteristics in the Songliao Basin:Implications from Continental Scientific Drilling

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Acta Geologica Sinica(English Edition) 2023年第5期97卷 1503-1522页

作者： HAN Shuangbiao HUANG Jie wang chengshan CUI Jiayi College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing 100083China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China

The lacustrine shale of deep Shahezi Formation in the Songliao basin has great gas potential,but its pore evolution,heterogeneity,and connectivity characteristics remain unclear.In this work,total organic carbon analysis,rock pyrolysis,X-ray diffraction field emission scanning electron microscopy,the particle and crack analysis system software,low-temperature nitrogen adsorption experiment,fractal theory,high-pressure mercury injection experiment and nuclear magnetic resonance experiment were used to study the Shahezi shale from Well SK-2.The result indicated that the organic pores in Shahezi shale are not developed,and the intergranular and intragranular pores are mainly formed by illitedominated clay.As the burial depth increases,the pore size and slit-shaped pores formed by clay decrease,and dissolved pores in the feldspar and carbonate minerals and dissolved fractures in the quartz increase.The pore evolution is affected by clay,compaction,and high-temperature corrosion.Based on the pore structure characteristics reflected by the pore size distribution and pore structure parameters obtained by multiple experimental methods,the pore development and evolution are divided into three stages.During stageⅠandⅡ,the pore heterogeneity of the shale reservoirs increases with the depth,the physical properties and pore connectivity deteriorate,but the gas-bearing property is good.In stageⅢ,the pore heterogeneity is the highest,its gas generation and storage capacity are low,but the increase of micro-fractures makes pore connectivity and gas-bearing better.

关键词： pore evolution pore connectivity gas-bearing deep shale Songliao basin

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一种以科研团队为服务对象的科研人员推荐模型

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数据分析与知识发现 2024年第3期8卷 132-142页

作者：刘成山李普国汪圳西安电子科技大学经济与管理学院西安710126 长安大学图书馆西安710064

【目的】本研究提出一种针对科研团队的深度学习组推荐模型,旨在满足科研团队招聘科研人员的需求,提高推荐效率。【方法】首先应用自注意力机制学习团队的语义表示,接着采用神经协同过滤模型学习团队与科研人员间的非线性关系,最终得到... 详细信息

【目的】本研究提出一种针对科研团队的深度学习组推荐模型,旨在满足科研团队招聘科研人员的需求,提高推荐效率。【方法】首先应用自注意力机制学习团队的语义表示,接着采用神经协同过滤模型学习团队与科研人员间的非线性关系,最终得到团队与人员的契合程度作为推荐的依据。【结果】实验结果显示,在公共数据集上,与基线模型相比,本文模型在推荐正确率和F1值上分别提高10.22和10.25个百分点,在实际推荐场景中表现优异。【局限】深度学习模型的参数量较小,仍有优化空间。【结论】本文模型可以有效提高科研人员招聘的效率,有助于科研服务机构提升服务水平,满足科研团队招聘人员的需求。

关键词：组推荐科研团队科研人员推荐自注意力机制

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CTDAE & CTODE models and their applications to power system stability analysis with time delays

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Science China(Technological Sciences) 2013年第5期56卷 1213-1223页

作者： YU XiaoDan JIA HongJie wang chengshan Key Laboratory of Smart Grid of Ministry of Education Tianjin University

In this paper,two new models suitable for power system stability analysis with considering time delays are derived.They are constraint time-delayed ordinary differential equation model(CTODE model) and constraint time-delayed differential algebraic equation model(CTDAE model).In these two models,dimension of the time-delayed equation is significantly reduced so as to speed up the calculation efficiency.Detail derivations to their nonlinear and incremental linear forms are given.And,some of their good features are discussed.Finally,a typical time-delayed system and single-machine-infinite-bus system are selected to validate the new models through Lyapunov-Krasovskii criterion and eigenvalue locus tracing procedure.It reveals that some unnecessary calculations in the algorithm can be avoided to achieve higher efficiency based on new models.The new models and new criterion given in this paper are helpful to design wide area protectors for bulk power systems.

关键词：时间延迟系统电力系统方程模型计算效率 E模型稳定分析微分代数 CTOD

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基于边缘计算的配电网数字化转型关键问题分析与展望

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电力系统自动化 2024年第6期48卷 29-41页

作者：李鹏习伟李鹏于浩王成山南方电网新型电力系统(北京)研究院有限公司北京市102209 智能电网教育部重点实验室(天津大学) 天津市300072

配电网是新型电力系统建设中最为关键和最具活力的环节之一。面向日益复杂的配电网运行与控制问题,数字化转型已成为广受认可的发展思路。边缘计算为数字配电网中海量数据资源和物理资源的利用提供了有效手段,同时也将作为配电网多种业... 详细信息

配电网是新型电力系统建设中最为关键和最具活力的环节之一。面向日益复杂的配电网运行与控制问题,数字化转型已成为广受认可的发展思路。边缘计算为数字配电网中海量数据资源和物理资源的利用提供了有效手段,同时也将作为配电网多种业务功能在边缘侧的融合承载平台,推动配电网运行架构的发展变革。文中围绕边缘计算技术驱动下的配电网数字化转型问题,梳理了配电网边缘计算装置的关键技术需求;分析了配电网边缘计算的技术定位及由其所支撑构建的数字配电网技术架构,特别针对数字配电网运行问题,从集群化、分布式、灵活定义3个典型特征入手,围绕边缘侧集群自治、边-边协调控制、云-边协同运行等典型模式下的关键问题和技术研究方向进行了分析与探讨。

关键词：配电网数字化边缘计算云-边协同

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资本下乡与新世纪乡土小说的发展

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山西大学学报(哲学社会科学版) 2024年第1期47卷 23-33页

作者：刘文祥王成珊河北大学文学院

资本下乡在新世纪乡村已成为一种常见现象。从目前来看，绝大部分乡土书写者都有意无意地忽视、排斥、批判资本下乡的现实，甚至认为资本下乡是乡村的终结，这使得乡村新经验并没有被及时处理和吸纳，不利于乡土小说的发展。不能仅仅将... 详细信息

资本下乡在新世纪乡村已成为一种常见现象。从目前来看，绝大部分乡土书写者都有意无意地忽视、排斥、批判资本下乡的现实，甚至认为资本下乡是乡村的终结，这使得乡村新经验并没有被及时处理和吸纳，不利于乡土小说的发展。不能仅仅将资本下乡当作一个事件，如果放置到乡土小说现代性进程中来看待，它也为我们理解新世纪乡土小说的症候及发展提供了一种新路径。资本下乡使得乡土书写和乡土社会结构之间形成了较难处理的紧张关系，也很容易将作为思想传统的乡村问题脱域化、现实化，带来乡村书写边界、知识分子与农民关系等的调整，并弱化乡土小说的地方色彩。资本下乡是乡土社会发展的必经阶段，对于我们重新检视乡土小说的发展、转换新世纪乡土小说的写作视点和方向、营造个性化的乡土写作等都具有一定的意义。

关键词：资本下乡新世纪乡土文学乡土小说

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Response of Reactive Phosphorus Burial to the Sedimentary Transition from Cretaceous Black Shales to Oceanic Red Beds in Southern Tibet

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Acta Geologica Sinica(English Edition) 2007年第6期81卷 1012-1018页

作者： HUANG Yongjian wang chengshan CHEN Xi State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Research Center for Tibetan Plateau Geology China University of Geosciences Beijing 100083 China

The mechanism of sedimentary transition from the Cretaceous black shales to the oceanic red beds is a new and important direction of Cretaceous research. Chemical sequential extraction is applied to study the burial records of reactive phosphorus in the black shale of the Gyabula Formation and oceanic red beds of the Chuangde Formation, Southern Tibet. Results indicate that the principal reactive phosphorus species is the authigenic and carbonate-associated phosphorus （CAP） in the Gyabula Formation and iron oxides-associated phosphorus （FeP） in the Chuangde Formation which accounts for more than half of their own total phosphorus content. While the authigenic and carbonate-associated phosphorus （CAP） is almost equal in the two Formations; the iron oxidesassociated phosphorus is about 1.6 times higher in the Chuangde Formation than that in the Gyabula Formation resulting in a higher content of the total phosphorus in the Chuangde Formation. According to the observations on the marine phosphorus cyde in Modern Ocean, it is found that preferential burial and regeneration of reactive phosphorus corresponds to highly oxic and reducing conditions, respectively, leading to the different distribution of phosphorus in these two distinct type of marine sediments. It is the redox-sensitive behavior of phosphorus cycle to the different redox conditions in the ocean and the controlling effects of phosphorus to the marine production that stimulate the local sedimentary transition from the Cretaceous black shale to the oceanic red beds.

关键词： Reactive phosphorus black shale oceanic red beds Cretaceous Southern Tibet China

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