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Spatiotemporal Variation of Plant Diversity Under a Unique Estuarine Wetland Gradient System in the Yellow River Delta, china

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chinese Geographical Science 2020年第2期30卷 217-232页

作者： SUN Jingkuan chi yuan FU Zhanyong LI Tian DONG Kaikai Shandong Key Laboratory of Eco-Environmental Science for Yellow River Delta Binzhou UniversityBinzhou 256603ShandongChina First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China

Multiple natural and human factors in estuarine wetlands result in complicated land surface characteristics with distinct spatial and temporal heterogeneities,thereby contributing to the difficulty in identifying spatiotemporal variations and influencing factors of plant diversity.A unique estuarine wetland gradient system(UEWGS)consisting of soil,vegetation,heat,distance,landscape,and anthropogenic gradients was established based on the ecological features of estuarine wetland through remote sensing and field investigation *** resolved the complicated land surface characteristics,covered all aspects of factors influencing plant diversity,and possessed distinct spatiotemporal *** Yellow River Delta,the largest estuarine wetland in the northern china,was selected as the study area to demonstrate UEWGS in four seasons in 2017.A total of 123 species were recorded with considerable seasonal *** australis,Suaeda salsa,and Tamarix chinensis were the dominant species,and crop species also played important *** single effect,all aspects of gradients exerted significant influences,yet only vegetation gradient possessed significant influences in all *** comprehensive effect,soil,vegetation,heat,and distance gradients showed significant gross *** content in soil gradient and net primary productivity in vegetation gradient possessed significant net influences in all seasons and can be considered as the main driving factor and indicator,respectively,of plant *** results validated the significance of UEWGS in revealing the plant diversity spatiotemporal characteristics and influencing factors,and UEWGS possessed universal applicability in the spatiotemporal analysis of plant diversity in estuarine areas.

关键词： plant diversity spatiotemporal variation single effect comprehensive effect Yellow River Delta

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Multi-objective Day-ahead Polarity Switching Optimization for Voltage Unbalance in Bipolar DC Distribution Networks

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Journal of Modern Power Systems and Clean Energy 2023年第4期11卷 1212-1223页

作者： Zhongchi Huang Qianggang Wang yuan chi Jianquan Liao Yu Zhang Niancheng Zhou Chongqing University ChongqingChina Sichuan University ChengduChina State Grid Chongqing Shibei Electric Power Supply Branch ChongqingChina

Bipolar direct current(DC)distribution networks can effectively improve the connection flexibility for renewable generations and *** practice,concerns regarding the potential voltage unbalance issue of the distribution networks and the frequency of switching still *** paper proposes a day-ahead polarity switching strategy to reduce voltage unbalance by optimally switching the polarity of renewable generations and loads while minimizing the switching times simultaneously in the range of a full ***,a multi-objective optimization model is constructed to minimize the weighted sum of voltage unbalance factors and the sum of number of switching actions in the day based on the power flow ***,a two-step solution strategy is proposed to solve the optimization ***,the proposed strategy is validated using 11-node and 34-node distribution networks as case studies,and a switching and stabilizing device is designed to enable unified switching of renewable generations and *** results demonstrate that the proposed strategy can effectively reduce the switching times without affecting the improvement of voltage balance.

关键词： Bipolar direct current(DC)distribution network multi-objective optimization renewable generation voltage unbalance

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基于阻抗灵敏度的MMC稳定性主导影响因素分析

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电力系统及其自动化学报 2024年第4期36卷 102-112页

作者：吴晓鸣沈玉明王绪利张辉段修超池源国网安徽省电力有限公司经济技术研究院合肥230000 重庆大学电气工程学院重庆400044

针对模块化多电平换流器的宽频谐振日益突出且涉及影响因素众多,通过参与因子分析难以宽频段定量寻找主导谐振因素的问题,提出模块化多电平换流器阻抗绝对灵敏度及标幺灵敏度的分析方法,来实现宽频谐振主导因素的定量研究,并降低模块化... 详细信息

针对模块化多电平换流器的宽频谐振日益突出且涉及影响因素众多,通过参与因子分析难以宽频段定量寻找主导谐振因素的问题,提出模块化多电平换流器阻抗绝对灵敏度及标幺灵敏度的分析方法,来实现宽频谐振主导因素的定量研究,并降低模块化多电平换流器的谐振风险。首先,建立模块化多电平换流器宽频阻抗模型,对延时环节和电流控制参数开展绝对灵敏度分析,来反映参数变化对系统稳定性的影响趋势;然后,对灵敏度比重标幺化消除各因素间量纲的影响,得到模块化多电平换流器互联系统在各频段稳定性的主导因素;最后,通过Matlab/Simulink模型验证了理论分析的正确性。

关键词：模块化多电平换流器宽频谐振主导因素阻抗模型灵敏度分析

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Study on Oxygen Potential of Ferromanganese Melt during Desiliconization

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Journal of Iron and Steel Research International 2001年第2期8卷 12-15页

作者： CHEN Er-bao DONG yuan-chi GUO Shang-xing East china University of Metallurgy

The first micro segregation under conditions of twin roll strip casting was simulated. The relationship between the temperature and solid fraction in the mushy zone was given. The temperatures such as ZDT, LIT were got from this simulation. Then using the turbulent model, the flow field and thermal field in the pool of twin roll strip caster was simulated. The speed and temperature at different casting speed was given, and the results were also explained. By these two simulations, the appropriate casting speed can be found. These simulations can provide effective data for controlling the twin roll strip casting process.

关键词： strip casting micro segregation solid fraction turbulence

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Comparative study of HFACS and the 24Model accident causation models

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Petroleum Science 2017年第3期14卷 570-578页

作者： Gui Fu Jia-Lin Cao Lin Zhou yuan-chi Xiang School of Resources and Safety Engineering China University of Mining and Technology (Beijing) Beijing 100083 China

A comparative study is conducted to compare the theory and application effect of two accident causation models, the human factors analysis and classification system（HFACS） and the accident causation ＂2-4＂ model（24 Model）, as well as to provide a reference for safety researchers and accident investigators to select an appropriate accident analysis method. The two models are compared in terms of their theoretical foundations, cause classifications, accident analysis processes, application ranges, and accident prevention strategies. A coal and gas outburst accident is then analyzed using both models, and the application results are compared. This study shows that both the 24 Model and HFACS have strong theoretical foundations, and they can each be applied in various domains. In addition, the cause classification in HFACS is more practical, and its accident analysis process is more convenient. On the other hand, the 24 Model includes external factors, which makes the cause analysis more systematic and comprehensive. Moreover, the 24 Model puts forward more corresponding measures to prevent accidents.

关键词： HFACS Accident causation "2-4" model Comparative study Unsafe acts External causes Coaland gas outburst accident

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Leaching process of phosphorus and iron from steelmaking slag into malic acid solution

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Journal of Iron and Steel Research International 2022年第6期29卷 951-960页

作者： Ning-ning Lv Chang Su Hui Kong Hai-chuan Wang yuan-chi Dong Key Laboratory of Metallurgical Emission Reduction and Resources Recycling Ministry of EducationAnhui University of TechnologyMa’anshan 243002AnhuiChina School of Metallurgical Engineering Anhui University of TechnologyMa’anshan 243002AnhuiChina

In order to remove phosphorus element from steelmaking slag and decrease iron loss,malic acid was selected as the leaching agent to dissolve steelmaking ***,the influences of different factors,such as malic acid concentration,slag particle size,temperature,liquid/solid ratio and stirring speed,on the leaching ratios of phosphorus and iron were ***,the kinetics for the leaching process of phosphorus was *** results showed that the leaching ratios of phosphorus and iron increase significantly with increasing the malic acid solution concentration and liquid/solid *** the concentration of malic acid solution increases up to 0.01492 mol/L,about 80%phosphorus can be dissolved,and iron leaching ratio is less than 17%.In addition,decreasing slag particle size can obviously increase the leaching ratio of ***,temperature and stirring speed have no significant effect on the dissolution of phosphorus and *** leaching kinetics of phosphorus follows the unreacted shrinking core *** through product layer is the rate-limiting step of the leaching process,and the corresponding apparent activation energy is determined to be 3.32 kJ/***,a semi-empirical kinetic equation was established.

关键词： Leaching process Steelmaking slag Phosphorus Iron Malic acid solution

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Risk factors for post-traumatic stress disorder among young and middle-aged cancer patients in the intensive care unit:A casecontrol study

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世界临床病例杂志 2023年第25期11卷 5870-5877页

作者： Lei Chen Guo-Zhou Wang yuan-yuan chi Jing Zhao Intensive Care Unit Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin’s Clinical Research Center for CancerTianjin 300060China Department of Intensive Care Unit Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin’s Clinical Research Center for CancerTianjin 300060China Nursing Department Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin’s Clinical Research Center for CancerTianjin 300060China

BACKGROUND Young and middle-aged cancer patients in intensive care unit(ICU)often suffer from stress and pressure,causing huge physical and mental ***,there is few research on post-traumatic stress disorder(PTSD)among young and middle-aged cancer patients in ICU in china,and the psychological status of patients who have experienced both cancer development and ICU stay is still *** To explore the risk factors for PTSD in young and middle-aged patients with cancer in *** Using convenient sampling method,we enrolled 150 young and middle-aged patients with cancer who were admitted to the ICU of our center during the period from July to December *** general data of the patients and PTSDrelated indicators were *** Impact of Event Scale-Revised(IES-R)was used for assessing PTSD one month after the discharge from the *** Logistic regression analysis was performed to assess the independent risk factors for PTSD in these *** Among these 150 patients,32(21.33%)were found to be with *** Logistic regression analysis revealed that factors significantly associated with PTSD among young and middle-aged patients with cancer in ICU included monthly income(OR=0.24,P=0.02),planned transfers(OR=0.208,P=0.019),and Acute Physiology and Chronic Health Evaluation(APACHE II)score(OR=1.171,P=0.003).CONCLUSION The low monthly income,unplanned transfers,and increased APACHE II score are the risk factors for PTSD in young and middle-aged patients with cancer in ICU.

关键词： Post-traumatic stress disorder Cancer Intensive care unit Risk factors

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Perturbation Solutions for Thermal Process of Honeycomb Regenerator

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Journal of Iron and Steel Research International 2007年第4期14卷 6-10,48页

作者： AI yuan-fang MEI chi HUANG Guo-dong JIANG Shao-iian School of Energy Science and Engineering Central South University Changsha 410083 Hunan China

A parameter perturbation for the unsteady-state heat-transfer characteristics of honeycomb regenerator is presented. It is limited to the cases where the storage matrix has a small wall thickness so that no temperature variation in the matrix perpendicular to the flow direction is considered. Starting from a two-phase transient thermal model for the gas and storage matrix, an approximate solution for regenerator heat transfer process is derived using the multiple-scale method for the limiting case where the longitudinal heat conduction of solid matrix is far less than the convective heat transfer between the gas and the solid. The regenerator temperature profiles are expressed as Taylor series of the coefficient of solid heat conduction item in the model. The analytical validity is shown by comparing the perturbation solution with the experiment and the numerical solution. The results show that it is possible for the perturbation to improve the effectiveness and economics of thermal research on regenerators.

关键词： honeycomb regenerator thermal process asymptotic analysis semi-analytic method

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基于预训练模型的药物不良事件抽取方法研究

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医学信息学杂志 2024年第2期45卷 38-43页

作者：袁驰李计巧王正瑶王怀玉河海大学计算机与软件学院南京211100 北京中医药大学国家中医体质与治未病研究院北京100029

目的/意义研究医学文本药物不良事件数据抽取方法,为临床用药风险管理和科学决策提供支持。方法/过程基于预训练模型,结合实体识别和关系抽取两个子任务的关联性,设计面向药物不良事件监测的实体关系联合抽取方法。结果/结论在公开药物... 详细信息

目的/意义研究医学文本药物不良事件数据抽取方法,为临床用药风险管理和科学决策提供支持。方法/过程基于预训练模型,结合实体识别和关系抽取两个子任务的关联性,设计面向药物不良事件监测的实体关系联合抽取方法。结果/结论在公开药物不良事件抽取数据集上的实验表明,该方法优于已有方法,能够有效地从医学文本中提取药物不良事件信息及其关系,为药物不良事件的发现与监测提供有力手段。

关键词：药物不良事件实体关系抽取预训练模型自然语言处理医学

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Cell-free biocatalysis coupled with photo-catalysis and electro-catalysis: Efficient CO2-to-chemical conversion

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Green Energy & Environment 2024年第9期9卷 1366-1383页

作者： Junzhu Yang chi-Kit Sou yuan Lu Key Laboratory of Industrial Biocatalysis Ministry of Education Tsinghua University Department of Chemical Engineering Tsinghua University

The increasing atmospheric carbon dioxide （CO2） concentration has exposed a series of crises in the earth's ecological *** to effectively fix and convert carbon dioxide into products with added value has attracted the attention of many ***-free enzyme catalytic system coupled with electrical and light have been a promising attempt in the field of biological carbon fixation in recent *** this review,the research progresses of photoenzyme catalysis,electroenzyme catalysis and photo-electroenzyme catalysis for converting carbon dioxide into chemical products in cell-free systems are systematically *** focus on reviewing and comparing various coupling methods and principles of photoenzyme catalysis and electroenzyme catalysis in cell-free systems,especially the materials used in the construction of the coupling system,and analyze and point out the characteristics and possible problems of different coupling ***,we discuss the major challenges and prospects of coupling physical signals and cell-free enzymatic catalytic systems in the field of CO2fixation,suggesting possible strategies to improve the carbon sequestration capacity of such systems.

关键词： CO 2 fixation Cell-free system Enzyme Photoenzyme catalysis Electroenzyme catalysis

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