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Journal of Modern Power Systems and Clean Energy 2022年第3期10卷 577-587页

作者： Jingwei Hu Xiaoyuan Xu hongyan ma Zheng Yan Key Laboratory of Control of Power Transmission and Conversion of Ministry of Education Shanghai Jiao Tong UniversityShanghaiChina Donghua University Shanghai 201620China

Transmission network expansion can significantly improve the penetration level of renewable generation.However,existing studies have not explicitly revealed and quantified the trade-off between the investment cost and penetration level of renewable generation.This paper proposes a distributionally robust optimization model to minimize the cost of transmission network expansion under uncertainty and maximize the penetration level of renewable generation.The proposed model includes distributionally robust joint chance constraints,which maximize the minimum expectation of the renewable utilization probability among a set of certain probability distributions within an ambiguity set.The proposed formulation yields a twostage robust optimization model with variable bounds of the uncertain sets,which is hard to solve.By applying the affine decision rule,second-order conic reformulation,and duality,we reformulate it into a single-stage standard robust optimization model and solve it efficiently via commercial solvers.Case studies are carried on the Garver 6-bus and IEEE 118-bus systems to illustrate the validity of the proposed method.

关键词： Affine decision rule distributionally robust optimization joint chance constraint renewable generation transmission network expansion planning

Research on Electricity Consumption Model of Library Building Based on Data Mining

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Energy Engineering 2022年第6期119卷 2407-2429页

作者： Jiaming Dou hongyan ma Rong Guo School of Electrical and Information Engineering Beijing University of Civil Engineering and ArchitectureBeijing102616China Institute of Distributed Energy Storage Safety Big Data Beijing University of Civil Engineering and ArchitectureBeijing102616China Beijing Key Laboratory of Intelligent Processing for Building Big Data Beijing102616China

With the exponential development of Chinese population,the massive energy consumption of buildings has recently become an interest subject.Although much research has been conducted on residential buildings,heating ventilation and air conditioning(HVAC),little research has been conducted on the relationship between student’s behavior,campus buildings,and their subsystems.Using classical seasonal decomposition,hierarchical clustering,and apriori algorithm,this paper aims to provide an empirical model for consumption data in campus library.Smart meter data from a library in Beijing,China,is adopted in this paper.Building electricity consumption patterns are investigated on an hourly/daily/monthly basis.According to the monthly analysis,electricity consumption peaks each year around June and December due to teaching programs,social exams,and outdoor temperatures.Hourly data analysis revealed a relatively stable consumption pattern.It shows three different types of daily load profiles.Daily data analysis demonstrated a high relationship between HVAC consumption and building total consumption,with a lift value of 5.9.Furthermore,links between temperature and subsystems were also discovered.Through a case study of library,this study provides a unique insight into campus electricity use.The results could help to develop operational strategies for campus facilities.

关键词： Electricity consumption data mining load profile campus building

Effects of transient temperature gradient on frost heave of saturated silty clay in an open system

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Research in Cold and Arid Regions 2023年第6期15卷 268-277页

作者： hongyan ma YuanFang Cui JianQiao Zhang Song Li Song Xu College of Civil Engineering Fuzhou UniversityFuzhouFujian 350108China Yunnan Construction and Investment Holding Co. LtdKunmingYunnan 650501China Ningbo Communications Planning Institute Co. LtdNingboZhejiang 315192China

Frost heave in seasonally frozen regions is a one-dimensional process that could severely damage infrastructure subgrades.Stress state,temperature and water migration are important factors for frost heave.This work investigated the effects of soil temperature and volumetric water content on the transient frost heave ratio during the freezing of saturated silty clay in an open system and analyzed the relationships between the transient frost heave ratio and freezing rate and between temperature gradient and frost heave rate.The results show that the frost heave ratio,frost heave rate,and freezing rate are positively correlated with the temperature gradient since the temperature gradient drives the water migration during freezing,indicating the transient temperature gradient could be used to evaluate the frost heave of saturated silty clay.The transient freezing rate and transient frost heave ratio are logarithmically related to the transient frost heave ratio and transient temperature gradient,respectively.The effects of transient temperature gradient on frost heave are the principal mechanism responsible for different frost heave characteristics and uneven frost heave along a subgrade of the same soil type.

关键词： Saturated silty clay Frost heave Transient temperature gradient Frost heave ratio Frost heave rate

Frequent detection of genetic aberrations reveals novel pathogenesis and treatment modalities in systemic juvenile xanthogranuloma

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Pediatric Investigation 2023年第3期7卷 212-215页

作者： Jiaosheng Xu hongyan ma Xingfeng Yao Xiaofeng Han Yang Wen Siwei Wang Zigang Xu Lin ma Department of Dermatology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Department of Dermatology Children’s Hospital of Xinjiang Uygur Autonomous RegionXinjiang Hospital of Beijing Children’s HospitalXinjiangChina Department of Pathology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Department of Radiology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Department of Ultrasound Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina

Juvenile xanthogranuloma(JXG),the most common form of non-Langerhans cell histiocytosis(non-LCH),is generally confined to the skin during infancy and early childhood.^(1)JXG rarely involves extracutaneous tissues or systemic organs,resulting in high morbidity and mortality rates.Clonality in JXG has been verified by histopathological and genetic analyses,which have shown it to be tumorous rather than a reactive disorder of JXG.^(2)However,the exact etiopathogenesis of JXG remains unclear.

关键词： treatment organs exact

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新喀里多尼亚的非殖民化:原因、进程与困境

世界民族 2024年第2期 102-112页

作者：赵少峰马红艳聊城大学太平洋岛国研究中心聊城252059

18世纪末新喀里多尼亚开始进入西方殖民统治视野,此后揭开了其与“文明”世界相互交织的碰撞史。自1853年法国吞并新喀里多尼亚后的170年时间里,双方之间的矛盾不断积聚,并发生了激烈冲突事件。按照《努美阿协定》,新喀里多尼亚在2018年... 详细信息

18世纪末新喀里多尼亚开始进入西方殖民统治视野,此后揭开了其与“文明”世界相互交织的碰撞史。自1853年法国吞并新喀里多尼亚后的170年时间里,双方之间的矛盾不断积聚,并发生了激烈冲突事件。按照《努美阿协定》,新喀里多尼亚在2018年、2020年和2021年举行了三次独立性公投,然而寻求独立的努力均以失败告终。从表面上看,新喀里多尼亚独立运动是独立派(原住民)与法国政府权力博奔的产物,但其实质是利益之争、族际冲突及认同混乱的结构性矛盾的体现。2021年,新喀里多尼亚举行的独立公投是最后一次公投行动,但是新喀里多尼亚独立派不认同公投结果并停止独立行动。就目前观察,在没有其他外部力量介入的情况下,新喀里多尼亚短期内很难实现完全独立。

关键词：新喀里多尼亚法国卡纳克人非殖民化

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耐低温菌固定化涂层电极处理印染废水的研究

水处理技术 2024年第3期50卷 103-107页

作者：郭洪丹马红艳天津科技大学化工与材料学院天津滨海新区300457

通过制备固定化涂层电极,将固定化技术和电化学技术结合,双重强化了耐低温菌处理印染废水的能力。对固定化涂层电极的性能进行了研究,对比了不同处理方式处理模拟印染废水的能力。结果表明:固定化涂层材料具有较好的机械强度,压缩应变达... 详细信息

通过制备固定化涂层电极,将固定化技术和电化学技术结合,双重强化了耐低温菌处理印染废水的能力。对固定化涂层电极的性能进行了研究,对比了不同处理方式处理模拟印染废水的能力。结果表明:固定化涂层材料具有较好的机械强度,压缩应变达95%以上,孔隙率为81.86%,溶胀率为302.76%;固定化涂层电极具有较好的电催化活性和较低的能耗,电极寿命是无涂层电极的2.17倍;固定化涂层电极电化学技术处理印染废水降解能力高于其他处理方式,脱色率为95.76%,化学需氧量(COD)去除率为84.16%,增强了菌株的降解能力,是一种有效的处理模拟印染废水的技术。

关键词：涂层电极电化学印染废水

Adsorption of cyclohexene and its dehydrogenation intermediates on nAu/Pt(100)(n = 0, 1, 2) surfaces: A DFT study

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Journal of Natural Gas Chemistry 2011年第1期20卷 34-40页

作者： hongyan ma Wenge Xu Zhenfeng Shang Guichang Wang Department of Chemistry and the Center of Theoretical and Computational Chemistry Nankai University Tianfin 300071 China College of Chemistry and Environmental Science Shanxi Datong University Datong 037009 Shanxi China

Adsorption of cyclohexene and its dehydrogenation intermediates on the nAu/Pt（100）（n = 0, 1, 2 means clean Pt, one monolayer and two layers of Au covered Pt surfaces, respectively.） has been investigated by self-consistent （GGA-PW91） density functional theory combined with periodic slab model. It is found that on the clean platinum, there are two kinds of favorable adsorption sites, i.e., hollow sites and bridge sites, and the adsorption energy at the hollow site is larger than that at the bridge site. However, on the Au/Pt and 2Au/Pt surfaces, there are three kinds of adsorption sites, and the adsorption energies are alike at both the bridge site and the top site. The magnitude order of the adsorption energies is as follows： clean Pt Au/Pt 2Au/Pt. The configurations of cyclohexene molecule have been distorted a little during the geometry optimizations. The lengths of C–M （M = Pt or Au, on the top layer of the slab） bonds are closely related to the corresponding adsorption energies.

关键词： cyclohexene dehydrogenation intermediates nAu/Pt（100） adsorption density functional theory

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计及配网电压越限的光储协同优化运行策略

储能科学与技术 2024年第3期13卷 893-902页

作者：顾怡邢洁马洪艳高杉东华大学信息科学与技术学院上海201620

随着大量分布式光伏(distributed photovoltaic,DPV)并网,目前配电网中出现了日间过压和夜间低压并存的电压越限问题,并进一步影响了网络的经济运行。本工作基于此提出了两阶段光储系统协同运行的优化调度策略。该策略第一阶段通过计算... 详细信息

随着大量分布式光伏(distributed photovoltaic,DPV)并网,目前配电网中出现了日间过压和夜间低压并存的电压越限问题,并进一步影响了网络的经济运行。本工作基于此提出了两阶段光储系统协同运行的优化调度策略。该策略第一阶段通过计算节点的电压灵敏度来确定待调节的储能节点与充放功率,以及光伏可调节点;第二阶段建立了光储运行优化模型。该模型以储能的调度成本、购售电成本以及网损成本之和最小为目标,以网络潮流、节点电压、储能SOC(state of charge)、光伏的无功可调容量等作为约束,通过粒子群算法对该模型进行求解,可以得到光储系统日调度出力策略。最后,以某地区31节点的实际配电网作为算例,验证了本工作方法的有效性。算例结果表明,该策略可以通过光储的协同调度,有效治理电网中的电压越限问题,并且在保障配电网电压安全的同时,实现优化运行成本的目标。

关键词：分布式光伏电压越限储能装置光伏无功运行优化

LiFePO_(4)/C cathode materials synthesized by co-precipitation and microwave heating

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Frontiers of Chemical Science and Engineering 2008年第4期2卷 422-427页

作者： Yunlong XU Lili TAO hongyan ma Huaqing HUANG Key Laboratory for Ultrafine materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

LiFePO_(4)/C cathode materials were synthesized by a combination of co-precipitation and microwave heat-ing using polyethylene glycol(PEG)as a carbon resource and the influence of microwave heating time on the struc-ture and electrochemical performance of the materials was also discussed.The samples were characterized by X-ray diffraction(XRD),TEM,particle-size analysis and con-stant current charge-discharge experiment.The results show that the LiFePO_(4)/C heated for 9 min has a pure olive-type phase and excellent electrochemical perform-ance.The initial discharge capacities of this sample are 154.3,139.7,123.9 mah/g at the rates 0.1C,0.2C,1C at room temperature,respectively,and after 20 cycles remain 152.3,134.3,118.5 mah/g,respectively.

关键词： lithium-ion battery cathode materials LiFePO_(4)/C microwave heating

Determination of allowable subgrade frost heave with the pavement roughness index in numerical analysis

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Research in Cold and Arid Regions 2015年第5期7卷 587-593页

作者： hongyan ma Feng Zhang DeCheng Feng Bo Lin School of Transportation Science and Engineering Harbin Institute of Technology

Frost heave is an upward swelling of soil during cryogenic conditions in cold regions. It is caused by the accumulation of ice crystals in subgrade soil, which grow upwards when freezing temperatures penetrate into the subgrade. This study establishes the allowable soil subgrade frost heave based on the roughness standard of asphalt pavement in China, and aims to balance the pavement design and frost heave resistance of subgrades in cold regions. We formulated a mechanical model of pavement supported by the boundary conditions of differential frost heave, based on the elastie layered system theory. The differential soil subgrade frost heave was modeled as a sinusoidal function, and the allowable frost heave and the roughness index were modeled as the displacement boundaries for the top and bottom of the pavement structure. Then the allowable frost heave was back-calculated according to the roughness standard. Numerical results show that the allowable frost heave depends on the pavement structure, material properties, the highway grade, and other factors. In order to ensure that the actual soil subgrade frost heave is lower than the allowable frost heave, pavement structures and materials need to be selected and designed carefully. The numerical method proposed here can be applied to establish the frost heave re- sistance of subgrade when the pavement structure and materials are determined.

关键词： differential frost heave asphalt pavement elastic layered system theory roughness index allowable frost heave