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Robust N−k Security-constrained Optimal Power Flow Incorporating Preventive and Corrective Generation Dispatch to Improve Power System Reliability

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CSEE Journal of Power and Energy Systems 2023年第1期9卷 351-364页

作者： Liping huang Chun Sing Lai zhuoli Zhao Guangya Yang Bang Zhong Loi Lei Lai School of Automation Guangdong University of TechnologyGuangzhou 510006China School of Automation Guangdong University of TechnologyGuangzhou 510006Chinaand also with the Department of Electronic and Electrical EngineeringBrunel University LondonLondonUB83PHUK Center for Electric Power System and Energy Department of Electrical EngineeringTechnical University of DenmarkKongens Lyngby 2800Demark Zhaoqing Power Supply Bureau Guangdong Power Grid CompanyChina Southern Power GridZhaoqing 526020China

As extreme weather events have become more frequent in recent years,improving the resilience and reliability of power systems has become an important area of concern.In this paper,a robust preventive-corrective security-constrained optimal power flow(RO-PCSCOPF)model is proposed to improve power system reliability under N−k outages.Both the short-term emergency limit(STL)and the long-term operating limit(LTL)of the post-contingency power flow on the branch are considered.Compared with the existing robust corrective SCOPF model that only considers STL or LTL,the proposed ROPCSCOPF model can achieve a more reliable generation dispatch solution.In addition,this paper also summarizes and compares the solution methods for solving the N−k SCOPF problem.The computational efficiency of the classical Benders decomposition(BD)method,robust optimization(RO)method,and line outage distribution factor(LODF)method are investigated on the IEEE 24-bus Reliability Test System and 118-bus system.Simulation results show that the BD method has the worst computation performance.The RO method and the LODF method have comparable performance.However,the LODF method can only be used for the preventive SCOPF and not for the corrective SCOPF.The RO method can be used for both.

关键词： Benders cut bender decomposition line outage distribution factor N−k security criterion optimal power flow power system reliability resilience robust optimization

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计及时空分布特性的光-荷典型场景提取方法

广东电力 2024年第2期37卷 25-32页

作者：钟富城王星华黎子律张岚麒杨炜康黄祥源赵卓立广东工业大学自动化学院广东广州510006

针对含光伏配电网中典型场景生成对光伏、负荷的时空相关性考虑不充足的问题,提出基于拉普拉斯矩阵降维及高斯混合模型的光伏、负荷典型场景提取法。首先利用光伏、负荷的历史运行数据构建光伏、负荷的日场景描述矩阵;再通过拉普拉斯特... 详细信息

针对含光伏配电网中典型场景生成对光伏、负荷的时空相关性考虑不充足的问题,提出基于拉普拉斯矩阵降维及高斯混合模型的光伏、负荷典型场景提取法。首先利用光伏、负荷的历史运行数据构建光伏、负荷的日场景描述矩阵;再通过拉普拉斯特征映射的降维,以及高斯混合模型得到描述矩阵的概率密度函数;最后经过Wasserstein距离筛选,完成光伏、负荷典型日场景提取。基于广东某地含光伏配电网的运行数据进行实验,对基于k-means聚类的场景生成法、拉丁超立方采样法以及所提场景联合方法进行对比,结果显示所提方法生成的典型场景与配电网实际运行场景的误差更小,速度更快,数量更少。

关键词：典型场景拉普拉斯映射 Wasserstein距离高斯混合模型场景描述矩阵

Ni镀层对Cu/Al钎焊接头界面组织与力学性能的影响

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河南科技大学学报（自然科学版） 2024年第4期45卷 23-29,M0003,M0004页

作者：张学智黄玲玲李云鹏于卓立曹新娜宋路阳安鹏涛魏世忠河南科技大学金属材料磨损控制与成型技术国家地方联合工程研究中心河南洛阳471023 河南科技大学材料科学与工程学院河南洛阳471023 郑州机械研究所有限公司新型钎焊材料与技术国家重点实验室河南郑州450001

为探究Ni-P镀层对Cu/Al异种金属钎焊界面反应的影响,采用化学镀方法对T2紫铜进行化学镀镍处理,使用BAl88Si药芯钎料通过感应钎焊方法钎焊Cu/Al接头。采用扫描电子显微镜和电子背散射衍射技术对接头进行微观组织观察与物相分析,并对接头... 详细信息

为探究Ni-P镀层对Cu/Al异种金属钎焊界面反应的影响,采用化学镀方法对T2紫铜进行化学镀镍处理,使用BAl88Si药芯钎料通过感应钎焊方法钎焊Cu/Al接头。采用扫描电子显微镜和电子背散射衍射技术对接头进行微观组织观察与物相分析,并对接头进行力学性能测试,分析镀层对Cu/Al接头微观组织结构及力学性能的影响,探讨钎焊过程中不同钎焊接头的界面形成机理。结果表明:无镀层接头在界面处形成了Cu_(9)Al_(4)和CuAl_(2)两层金属间化合物,有镀层接头界面处形成了Al_(2)Ni和Al_(3)Ni金属间化合物。无镀层接头的抗拉强度可达56.4 MPa,优于有镀层接头。接头均发生脆性断裂,断裂位置从无镀层接头的CuAl2和α-Al固溶体的界面处转变为有镀层接头的Al3Ni金属间化合物处。

关键词： Cu/Al异种金属 Ni-P镀层金属间化合物微观组织力学性能

Flare and change in disease activity among patients with stable rheumatoid arthritis following coronavirus disease 2019 vaccination: A prospective Chinese cohort study

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中华医学杂志（英文版） 2023年第19期136卷 2324-2329页

作者： Yan Geng Yong Fan Yu Wang Xuerong Deng Lanlan Ji Xiaohui Zhang Zhibo Song Hong huang Yanni Gui Haoze Zhang Xiaoying Sun Guangtao Li Juan Zhao zhuoli Zhang China 100034

Background: Vaccination has been shown effective in controlling the global coronavirus disease 2019 (COVID-19) pandemic and reducing severe cases. This study was to assess the flare and change in disease activity after COVID-19 vaccination in patients with stable rheumatoid arthritis (RA). Methods: A prospective cohort of RA patients in remission or with low disease activity was divided into a vaccination group and a non-vaccination group based on their COVID-19 vaccination status. Each of them was examined every 3 to 6 months. In the vaccination group, disease activity was compared before and after vaccination. The rates of flare defined as disease activity scores based on 28-joint count (DAS28) >3.2 with ΔDAS28 ≥0.6 were compared between vaccination and non-vaccination groups. Results: A total of 202 eligible RA patients were enrolled. Of these, 98 patients received no vaccine shot (non-vaccination group), and 104 patients received two doses of vaccine (vaccination group). The median time interval from pre-vaccination visit to the first immunization and from the second dose of vaccine to post-vaccination visit was 67 days and 83 days, respectively. The disease activity scores at pre-vaccination and post-vaccination visits in the vaccination group patients were similar. At enrollment, gender, RA disease course, seropositivity, and disease activity were comparable across the two groups. Flare was observed in five (4.8%) of the vaccination group patients and nine (9.2%) of the non-vaccination group patients at post-vaccination assessment ( P = 0.221). In terms of safety, 29 (27.9%) patients experienced adverse events (AEs) after vaccination. No serious AEs occurred. Conclusions: COVID-19 vaccinations had no significant effect on disease activity or risk of flare in RA patients in remission or with low disease activity. Patients with stable RA should be encouraged to receive the COVID-19 vaccination.

关键词： COVID-19 vaccination Rheumatoid arthritis Disease activity Flare Adverse events

Autonomous driving: cognitive construction and situation understanding

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Science China(Information Sciences) 2019年第8期62卷 75-101页

作者： Shitao CHEN Zhiqiang JIAN Yuhao huang Yu CHEN zhuoli ZHOU Nanning ZHENG Institute of Artificial Intelligence and Robotics Xi'an Jiaotong University National Engineering Laboratory for Visual Information Processing and Applications

Autonomous vehicle is a kind of typical complex artificial intelligence system. In current research of autonomous driving, the most widely adopted technique is to use a basic framework of serial information processing and computations, which consists of four modules: perception, planning, decision-making, and control. However, this framework based on data-driven computing performs low computational efficiency,poor environmental understanding and self-learning ability. A neglected problem has long been how to understand and process environmental perception data from the sensors referring to the cognitive psychology level of the human driving process. The key to solving this problem is to construct a computing model with selective attention and self-learning ability for autonomous driving, which is supposed to possess the mechanism of memorizing, inferring and experiential updating, enabling it to cope with traffic scenarios with high noise, dynamic, and randomness. In addition, for the process of understanding traffic scenes,the efficiency of event-related mechanism is more significant than single-attribute scenario perception data.Therefore, an effective self-driving method should not be confined to the traditional computing framework of‘perception, planning, decision-making, and control’. It is necessary to explore a basic computing framework that conforms to human driver’s attention, reasoning, learning, and decision-making mechanism with regard to traffic scenarios and build an autonomous system inspired by biological intelligence. In this article, we review the basic methods and main progress in current data-driven autonomous driving technologies, deeply analyze the limitations and major problems faced by related algorithms. Then, combined with authors’ research, this study discusses how to implement a basic cognitive computing framework of self-driving with selective attention and an event-driven mechanism from the basic viewpoint of cognitive science. It further describes how to use multi-sensor and graph d

关键词： autonomous driving event-driven mechanism cognitive construction situation understanding intuitive reasoning

Current health resources required for the management of ankylosing spondylitis in developing areas of China

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Chinese Medical Journal 2023年第6期136卷 737-739页

作者： Yi Zhao Qian Wang Lihua Duan Xinxiang huang Pei Wang Ping Fan Qinghua Zou Zhiming Lin Jiuliang Zhao Xin Wu Li Wang Yan Gen Xiaoxia Zhu zhuoli Zhang Wen Zhang Yan Zhao Department of Rheumatology and Immunology West China HospitalSichuan UniversityChengduSichuan 610041China Clinical Institute of Inflammation and Immunology(CIII) Frontiers Science Center for Disease-related Molecular NetworkWest China HospitalSichuan UniversityChengduSichuan 610041China Department of Rheumatology Peking Union Medical College HospitalPeking Union Medical College&Chinese Academy of Medical SciencesNational Clinical Research Center for Dermatologic and Immunologic Diseases(NCRC-DID)Key Laboratory of Rheumatology and Clinical ImmunologyMinistry of EducationBeijing 100730China Department of Rheumatology and Clinical Immunology Jiangxi Provincial People’s HospitalNanchangJiangxi 330006China Department of Rheumatology The People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous Region 530021China Department of Rheumatology and Immunology Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityZhengzhouHenan 450003China Department of Rheumatism and Immunology The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’anShaanxi 710061China Department of Rheumatology and Immunology The First Hospital Affiliated to Army Medical UniversityChongqing 400038China Department of Rheumatology The Third Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou 510630China Department of Rheumatology and Immunology Shanghai Changzheng HospitalThe Second Military Medical UniversityShanghai 200003China Department of Rheumatology and Clinical Immunology Peking University First HospitalBeijing 100034China Department of Rheumatology Huashan Hospital and Fudan UniversityShanghai 200040China

To the Editor:Ankylosing spondylitis(AS)is a chronic inflammatory disease that causes bony fusion of spine and sacroiliac joints,resulting in restricted spinal movement and deformity.In China,the prevalence of AS is about 0.29%with a male to female ratio of approximately 3:1,and most cases occur in the adolescent period.[1]The misdiagnosis rate of AS patients in China is>50%.

关键词： spondylitis prevalence restricted

柴达木盆地尕斯库勒盐湖区邻近水体对湖泊微生物群落的贡献

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微生物学报 2023年第6期63卷 2094-2108页

作者：赵卓丽黄建蓉韩积斌蒋宏忱中国地质大学(北京)海洋学院北京100083 中国科学院青海盐湖研究所青海省盐湖地质与环境重点实验室青海西宁810008 中国地质大学(武汉)生物地质与环境地质国家重点实验室湖北武汉430074

【目的】探究尕斯库勒盐湖生态系统中邻近水体对湖泊微生物的贡献。【方法】采集尕斯库勒盐湖区湖水、沉积物以及邻近的泉水、河水和盐田的水样,对其进行地球化学分析;通过16S rRNA基因的Illumina MiSeq高通量测序分析样品的微生物群落... 详细信息

【目的】探究尕斯库勒盐湖生态系统中邻近水体对湖泊微生物的贡献。【方法】采集尕斯库勒盐湖区湖水、沉积物以及邻近的泉水、河水和盐田的水样,对其进行地球化学分析;通过16S rRNA基因的Illumina MiSeq高通量测序分析样品的微生物群落组成。【结果】尕斯库勒盐湖区水体和沉积物中的优势门是变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、放线菌门(Actinobacteria)和广古菌门(Euryarchaeota)。盐度和pH是影响尕斯库勒盐湖区群落组成的最主要环境因素。邻近水体对湖泊水体和沉积物的贡献分别为12.94%和7.53%。【结论】邻近水体对尕斯库勒盐湖微生物群落的贡献有限。

关键词：尕斯库勒盐湖微生物群落邻近水体贡献

抗风湿药物胃肠道损伤管理中国专家共识(2024版)

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中华风湿病学杂志 2024年第5期28卷 293-302页

作者：黄红段利华姜林娣谈文峰薛静程永静李景南吕宾吴开春张卓莉赵岩中华医学会风湿病学分会中国初级卫生保健基金会风湿免疫学专委会北京大学第一医院风湿免疫科北京100034 江西省人民医院风湿免疫科南昌330006 复旦大学附属中山医院风湿免疫科上海200032 江苏省人民医院风湿免疫科南京210029 浙江大学医学院附属第二医院风湿免疫科杭州310003 北京医院风湿免疫科北京100005 北京协和医院消化科北京100730 浙江中医药大学附属第一医院消化科杭州310006 西京医院消化科西安710032 北京协和医院风湿免疫科北京100730 不详

风湿免疫病患者在接受抗风湿药物治疗过程中可能出现一系列不良反应,其中胃肠道损伤较为常见。由抗风湿药物引起的胃肠道损伤不仅危害患者健康,而且显著增加了医疗费用。为了使临床医生科学、规范地管理抗风湿药物相关的胃肠道损伤,本... 详细信息

风湿免疫病患者在接受抗风湿药物治疗过程中可能出现一系列不良反应,其中胃肠道损伤较为常见。由抗风湿药物引起的胃肠道损伤不仅危害患者健康,而且显著增加了医疗费用。为了使临床医生科学、规范地管理抗风湿药物相关的胃肠道损伤,本共识团队通过对常用抗风湿药物相关胃肠道不良事件及防治方法进行文献检索、文献质量评价,基于循证医学证据制定了《抗风湿药物胃肠道损伤管理中国专家共识》。该共识包括总则的3条陈述和细则的12条推荐意见,提出了风湿免疫病对胃肠道的影响及其表现,抗风湿药物引起胃肠道损伤的机制,风湿免疫病患者服用抗风湿药物相关胃肠道损伤的危险因素,以及抗风湿药物相关胃肠道损伤的防治方法,用于指导临床实践。

关键词：风湿免疫病抗风湿药物胃肠道损伤干预措施共识

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某总温总压受感器热电偶结构优化设计

中国测试 2023年第12期49卷 73-78页

作者：张卓利王佳伟董伟超黄开放中国飞行试验研究院陕西西安710089

该文针对某总温总压受感器在振动试验过程中K型铠装热电偶断裂的故障,进行原因分析和改进。将铠装热电偶更换为带编织绝缘层的K型热电偶,采用双孔瓷管作为热电偶丝和壳体之间的绝缘和固定元件,设计尾部电缆固线套。通过模拟仿真和数值... 详细信息

该文针对某总温总压受感器在振动试验过程中K型铠装热电偶断裂的故障,进行原因分析和改进。将铠装热电偶更换为带编织绝缘层的K型热电偶,采用双孔瓷管作为热电偶丝和壳体之间的绝缘和固定元件,设计尾部电缆固线套。通过模拟仿真和数值计算的方法对时间常数指标进行分析,采用增大总温总压受感器阻滞腔排气孔尺寸的方法,将阻滞腔内平均内流速度由22.047 m/s提高到41.835 m/s,计算理论时间常数由1.01 s降为0.688 s。通过温度特性校准,受感器测量精度满足Ⅰ级K型热电偶的精度要求;经时间常数试验校准,在来流马赫数Ma为0.3,高度H为0条件下,时间常数变化范围为0.860~0.930 s;通过强化振动循环试验验证,产品功能性能正常,提高了产品可靠性。

关键词：铠装热电偶时间常数阻滞腔内流速度