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一种考虑风力机实际大转动惯量的改进最优转矩法

第37届中国控制会议

作者： ankang cao Lihui Cen Jia Chen School of Information Science and Engineering Central south university

The paper deals with the maximum power point tracking（MPPT） problem in large-scale wind turbine systems. The inertia of the large-scale wind turbine is very big and the optimal torque control（OTC） only considers the steady-state operating point of the system, leading to a long tracking time. For the existing sliding mode control（SMC） based on OTC, the MPPT efficiency is improved at the cost of the fluctuation of generator torque. In this paper, a sliding mode controller with variable parameter is proposed for improving MPPT efficiency. Compared with the existing control strategies, the performance of the proposed method is validated by using a FAST（Fatigue, Aerodynamic, Structure, and Turbulence） model based on the 5 MW wind turbine. Simulation results clearly show that a more rapid speed response could be obtained through the proposed method,while the power capture efficiency is increased and the fluctuation of generation torque is decreased.

关键词： large-scale wind turbine maximum power point tracking optimal torque control sliding mode control

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太阳能学报 2021年第6期42卷 297-303页

作者：陈佳岑丽辉曹安康刘芳中南大学自动化学院长沙410083

考虑实际大型风力机的大转动惯量,在传统最优转矩控制方法的基础上,提出一种增大加速转矩(IAT)的改进方法,缩短系统的调节时间,以此提高风力机的性能。通过建立小信号分析方法,与最优转矩法相比,证明该方法具有更好的动态特性。最后,在... 详细信息

考虑实际大型风力机的大转动惯量,在传统最优转矩控制方法的基础上,提出一种增大加速转矩(IAT)的改进方法,缩短系统的调节时间,以此提高风力机的性能。通过建立小信号分析方法,与最优转矩法相比,证明该方法具有更好的动态特性。最后,在风力机专业仿真软件FAST中进行对比仿真,在不同风况下验证所提出的改进方法具有更好的风能捕获效率。

关键词：风力机最大功率点惯量最优转矩法

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几种根际微生物的时空分布的初步探究

微生物前沿 2017年第3期6卷 57-64页

作者：严畅曹安康邢辉南京师范大学附属中学江苏南京

根际微生物的活动在植物的根际营养中起着分解有机物、释放与贮蓄养分的积极作用。根际促生微生物可以通过影响植物根系形态及生理特征而影响植物对养分的吸收,根际生防微生物通过产生一些抗菌物质抑制病原菌在植物根际的生殖和发展。然... 详细信息

根际微生物的活动在植物的根际营养中起着分解有机物、释放与贮蓄养分的积极作用。根际促生微生物可以通过影响植物根系形态及生理特征而影响植物对养分的吸收,根际生防微生物通过产生一些抗菌物质抑制病原菌在植物根际的生殖和发展。然而,由于土壤中微生物个体微小,数量多,分离和鉴定困难,土壤环境条件复杂等原因,限制了人们对根际微生物与植被相互关系的认知。因此,本研究选择五种具有代表性的植物,在不同季节取其根际土中的微生物置于酵母膏,琼脂,PDA,高氏一号四种培养基培养,运用菌落计数研究了同种植物微生物量随季节变化的规律及不同植物微生物类群结构的异同,试图解释根际微生物数量和结构与植被和季节的相互关系。

关键词：根际微生物时空分布

“高中生幽门螺杆菌感染情况调查”研究性学习案例

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生物学通报 2021年第8期56卷 25-27页

作者：李旭曹安康邢辉南京师范大学附属中学江苏南京210003

从生活中常见胃病与饮食之间的关系入手,通过学习文献,了解到常见胃病多与幽门螺杆菌有关联,制定了“高中生幽门螺杆菌感染情况调查”研究计划,对一定数量的高中生开展了幽门螺杆菌感染情况的调查,旨在分析高中生群体幽门螺杆菌感染与... 详细信息

从生活中常见胃病与饮食之间的关系入手,通过学习文献,了解到常见胃病多与幽门螺杆菌有关联,制定了“高中生幽门螺杆菌感染情况调查”研究计划,对一定数量的高中生开展了幽门螺杆菌感染情况的调查,旨在分析高中生群体幽门螺杆菌感染与日常饮食之间的关系。学生通过此项研究,提高了科学探究能力,养成科学思维的习惯,形成积极的科学态度,发展终身学习的能力。

关键词：幽门螺杆菌感染饮食研究性学习

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固定化酵母菌实验条件的探究和改进

生物学通报 2019年第7期54卷 48-50页

作者：殷亚妮许东升吉祖筠曹安康南京师范大学附属中学

探究了海藻酸钠浓度(4%、7%和10%)、固定化时间(10 min、20 min、30 min、40 min和50 min),以及CaCl2浓度对酵母菌固定化效果和时间的影响。结果表明,在考虑时间成本的情况下,使用7%浓度的海藻酸钠,在0.05 mol/L的CaCl2溶液中固定20~30 ... 详细信息

探究了海藻酸钠浓度(4%、7%和10%)、固定化时间(10 min、20 min、30 min、40 min和50 min),以及CaCl2浓度对酵母菌固定化效果和时间的影响。结果表明,在考虑时间成本的情况下,使用7%浓度的海藻酸钠,在0.05 mol/L的CaCl2溶液中固定20~30 min形成的凝胶珠形态最佳,固定酵母菌效果最佳。如果增加CaCl2溶液的浓度,则固定化时间可等比缩短,例如在2 mol/L的CaCl2溶液中只需固定7.5 min。

关键词：酵母菌固定化海藻酸钠 CaCl2浓度固定化时间简易成形装置

Spatial distribution characteristics and influence factor analysis of landslides——case study of the Hanwang area in Qinba Mountains

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Earthquake Research Advances 2024年第3期4卷 55-65页

作者： Jikai Zhang Yanbo cao Wen Fan Wenbo Zheng Zequan Wang Chengcheng He Hongquan Teng School of Geological Engineering and Geomatics Chang’an UniversityXi'an710054China Mine Geological Disasters Mechanism and Prevention Key Laboratory Xi'an710054China China DK Comprehensive Investigate and Design Research Institute Co. Ltd.Xi'an710054China Shaanxi Engineering Technology Research Center for Urban Geology and Underground Space Xi'an710068China Shaanxi Hydrogeology Engineering Geology and Environment Geology Survey CenterXi'an710068China Chang'an University Xi'anShaanxiChina

The geological hazards of landslides in Hanwang Town, Ziyang County, ankang City, Shaanxi Province, have emerged. Yet, the current understanding of the spatial distribution characteristics and influencing factors of landslides in this area remains unclear. Combining the results of remote sensing interpretation and field investigation, seven influencing factors, namely, elevation, slope direction, slope gradient, distance from rivers, distance from faults, engineering geologic lithology, and distance from roads, are selected for the study. The distribution characteristics of landslides in each influencing factor and the influence of the resolution of the Digital Elevation Model(DEM) on the results are statistically and analytically analyzed. Furthermore, two highrisk landslides within the study area were subjected to comprehensive analysis, integrating the findings from drilling and other field investigations in order to examine their deformation mechanisms. Based on this analysis,the following conclusions were derived:(1) 34 landslides in the study area, mainly small earth landslides, with a distribution density of 0.42/km~2, threatening 414 people and property of about 55.87 million Yuan.(2)The landslides in the study area easily occur in the <400 m elevation range;the landslides are developed in all slope directions, the gradient is mainly concentrated in the range of 10°–40°, the distribution density of the landslides is higher in the closer distance from the river and the faults(0–200 m), the landslide-prone strata are mainly the softer and weaker metamorphic rocks, and the landslides are mainly around roads.(3) The resolution of the DEM should be selected based on the specific conditions of the study area, the requirements of the investigation, and the scale of the landslide. Opting for an appropriate DEM resolution is advantageous for understanding the patterns of landslides and conducting risk assessments in the region.(4) The Zhengjiabian landslide is a trac

关键词： Landslide Spatial distribution Influence factor Landslide density Deformation mechanism DEM

Discovering a formula for the high temperature oxidation behavior of FeCrAlCoNi based high entropy alloys by domain knowledge-guided machine learning

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Journal of Materials Science & Technology 2023年第18期149卷 237-246页

作者： Qinghua Wei Bin cao Lucheng Deng ankang Sun Ziqiang Dong Tong-Yi Zhang Materials Genome Institute Shanghai UniversityShanghai 200444China Hong Kong University of Science and Technology(Guangzhou) Guangzhou 511458China

A mathematical formula of high physical interpretation,and accurate prediction and large generaliza-tion power is highly desirable for science,technology and *** this study,we performed a domain knowledge-guided machine learning to discover high interpretive formula describing the high-temperature oxidation behavior of FeCrAlCoNi-based high entropy alloys(HEAs).The domain knowledge suggests that the exposure time dependent and thermally activated oxidation behavior can be described by the synergy formula of power law multiplying Arrhenius *** pre-factor,time exponent(m),and activation energy(Q)are dependent on the chemical compositions of eight elements in the FeCrAlCoNi-based *** Tree-Classifier for Linear Regression(TCLR)algorithm utilizes the two exper-imental features of exposure time(t)and temperature(T)to extract the spectrums of activation energy(Q)and time exponent(m)from the complex and high dimensional feature space,which automatically gives the spectrum of *** three spectrums are assembled by using the element features,which leads to a general and interpretive formula with high prediction accuracy of the determination coefficient R^(2)=*** role of each chemical element in the high-temperature oxidation behavior is analytically illustrated in the three spectrums,thereby the discovered interpretative formula provides a guidance to the inverse design of HEAs against high-temperature *** present work demonstrates the sig-nificance of domain knowledge in the development of materials informatics.

关键词： Domain knowledge Interpretive formula High entropy alloys Oxidation

Characteristics of rural domestic sewage discharge and their driving mechanisms: evidence from the Northern Region, China

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 47-58页

作者： Jianguo Liu Ziyu Zhou Pengyu Li Zixuan Wang Ying Yan Xuezheng Yu Wenkai Li Tianlong Zheng Yingnan cao Wenjun Wu Wenqian Cai Zhining Shi Junxin Liu Key Laboratory of Environmental Pollution Control and Remediation at Universities of Inner Mongolia Autonomous Region College of Resources and Environmental EngineeringInner Mongolia University of TechnologyHohhot 010051China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China SCEGC No.12 Construction Engineering Group Co. Ltd.Ankang 725000China State Environmental Protection Key Laboratory of Environmental Planning and Policy Simulation Chinese Academy of Environmental PlanningBeijing 100041China Technical Centre for Soil Agriculture and Rural Ecology and EnvironmentMinistry of Ecology and EnvironmentBeijing 100012China Sustainable Infrastructure and Resource Management(SIRM) UniSA STEMUniversity of South AustraliaSouth AustraliaMawson LakesSA 5095Australia

The traits of rural domestic sewage emission are unclear,negatively affecting rural domestic sewage treatment and sewage *** study used data from the Second National Pollution Source Census Bulletin to establish a data *** spatial distribution characteristics and main factors influencing rural sewage discharge in the Northern Region were studied using spatial autocorrelation analysis and structural *** findings demonstrated that(l)a significant Spearman correlation between drainage water volume(DwV),chemical oxygen demand(COD),ammonia nitrogen(NH_(3)-N),total nitrogen(TN),and total phosphorus(TP)and that the correlation coefficients between DWV and COD,NH,-N,TNand TP were 0.87**,1.0**,0.99**,0.99**,respectively;(2)rural sewage discharge showed spatial autocorrelation,and rural domestic sewage discharge in the districts and counties with an administration was significantly higher than in the surrounding areas;and(3)social development was the main driver rural domestic sewage changes(path coefficient was 0.407**),and the main factors influencing rural domestic sewage discharge were the urbanization rate,years of education,and population age *** study obtained the spatial variation law and clarified the main influencing factors of rural domestic sewage to provide data support and a theoretical basis for subsequent rural sewage collection and *** of the Inner Mongolia Autonomous Region in northern China as a typical case,provides a theoretical foundation for scientific decision-making on rural domestic sewage treatment at the national and regional levels and offers new perspectives for managing pollutants.

关键词： Rural domestic sewage Emission characteristics Spatial autocorrelation analysis Influencing factors

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真空绝热板使用寿命数值分析及预测

真空科学与技术学报 2014年第7期34卷 665-671页

作者：阚安康康利云曹丹上海海事大学商船学院上海201306

真空绝热板(VIPs)的长期稳定性已经成为诸多研究单位、生产企业和使用者最为关心的问题之一。文章建立了相应的使用寿命预测数学模型,并对不同多孔介质芯材的VIPs使用寿命进行了数值分析及预测。采用实验结果与预测数学模型进行了对比分... 详细信息

真空绝热板(VIPs)的长期稳定性已经成为诸多研究单位、生产企业和使用者最为关心的问题之一。文章建立了相应的使用寿命预测数学模型,并对不同多孔介质芯材的VIPs使用寿命进行了数值分析及预测。采用实验结果与预测数学模型进行了对比分析,两者吻合较好。提出了延长使用寿命的措施,设计了可降阶反气体渗透的方法用以延长VIPs的使用寿命。文章所建立的数学模型及分析方法对VIPs的生产和推广应用具有指导意义。

关键词：真空绝热板使用寿命导热系数影响因素数值分析及预测