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飞行器多因素突发性灾难事故的预防及其算法

航空学报 2007年第1期28卷 146-150页

作者：冯蕴雯宣建林国志刚冯元生西北工业大学飞行器设计研究所陕西西安710072

首先指出多因素引起的突发性灾难事故现仍偶有发生,虽然其发生次数不多,但性质是严重的。阐明多因素失效灾难性事故的预防方法,提出有工程实际意义的截断事故链中关键链的概念与方法,提出与建立针对多因素失效的可靠性分析方法,并提出... 详细信息

首先指出多因素引起的突发性灾难事故现仍偶有发生,虽然其发生次数不多,但性质是严重的。阐明多因素失效灾难性事故的预防方法,提出有工程实际意义的截断事故链中关键链的概念与方法,提出与建立针对多因素失效的可靠性分析方法,并提出如何在飞机上建立相应的健康监控设施及其算法。

关键词：突发性灾难事故多因素失效截断事故链健康监控可靠性分析

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强流脉冲离子束辐照效应的数值模拟研究进展

材料导报 2009年第S1期23卷 241-245页

作者：丰新宇张罡沈阳理工大学中俄联合高能束流实验室

强流脉冲离子束(HIPIB)作为一种新型的表面改性技术在表面工程领域具有广阔的应用前景。综述了计算机模拟HIPIB辐照效应的国内外研究进展,对不同类型辐照效应的模拟结果进行了系统分析,为进一步探索HIPIB的辐照机理提供了参考依据。

关键词：强流脉冲离子束 HIPIB辐照效应数值模拟

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复配催化体系制备双峰分布的聚乙烯

石油化工 2000年第5期29卷 341-344页

作者：田锋陈伟郑刚景振华石油化工科学研究院北京100083

利用茂金属加合物和一种Ziegler-Natta钛系催化剂复配而成的催化体系 ,制备相对分子质量呈双峰分布的聚乙烯。考查了复配催化体系中茂金属加合物和钛系催化剂的配比对聚合物相对分子质量、相对分子质量分布及结构性能的影响。

关键词：相对分子质量双峰分布乙烯聚合聚乙烯催化

Distribution patterns of landslides triggered by the 2022 Ms 6.8 Luding earthquake,Sichuan,China

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山地科学学报（英文） 2023年第3期20卷 607-623页

作者： ZHANG Jian-qiang YANG Zong-ji MENG Qing-kai WANG Jiao HU Kai-heng GE Yong-gang SU feng-huan ZHAO Bo ZHANG Bo JIANG Ning HUANG Yu MING Zai-yang ZHANG Yi-fan LIU Zhen-xing WU Chun-hao ZHOU Wen-tao LIANG Xin-yue SUN Yu-qing YANG Lian-bing YAO Hong-kun feng Pei-hua LIU Jia-li Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Bejing 100049China East China University of Technology Nanchang 330013China Institute of Geographic Sciences and Natural Resources Research Beijing 100101China Chongqing Jiaotong University Chongqing 400074China

At 12:52 pm on September 5,2022,an Ms 6.8 earthquake occurred in Luding County,Sichuan Province,*** on high-resolution aerial photographs and satellite imageries obtained after the earthquake,as well as field investigation,a total of 8685 earthquake-triggered landslides(EQTLs)were *** landslides covered an area of 30.7km^(2),with a source area of 9.4 km^(2).These EQTLs were mainly distributed in areas with a seismic intensity of VIII and *** of the landslides were small and medium in size,and their types included landslide,rockfall,and rock *** landslide distributions were found,EQTLs were distributed along the Xianshuihe fault,landslide area decreased gradually with an increased distance to the fault;EQTLs were distributed along the Daduhe River and roads;besides,landslide distribution was associated with ground deformation caused by the ***’characteristics indicated that,a large number of EQTLs were located near the foot of the slope;the full area of EQTLs and their source area followed a power *** study concluded that Luding EQTLs were greater in number and area but relatively smaller in terms of affected *** on geo-hazards post-earthquake and risk assessment were proposed in the earthquake-stricken area to support the rehabilitation and reconstruction.

关键词： 2022 Luding earthquake Earthquaketriggered landslide Landslide inventory Distribution patterns

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泰国旅华市场时空结构与拓展策略研究

世界地理研究 2015年第4期24卷 142-151页

作者：周成冯学钢华东师范大学经济与管理学部上海200241

泰国旅华客源市场在我国入境旅游市场中一直占有重要比重。基于大量统计数据,运用时间变化强度指数、季节性强度指数和地理集中指数等定量方法,从时间和空间两个维度对泰国旅华市场的时空结构特征及演化规律进行系统性研究。结果表明:... 详细信息

泰国旅华客源市场在我国入境旅游市场中一直占有重要比重。基于大量统计数据,运用时间变化强度指数、季节性强度指数和地理集中指数等定量方法,从时间和空间两个维度对泰国旅华市场的时空结构特征及演化规律进行系统性研究。结果表明:时间上,泰国旅华市场从1985年~2012年经历了初始发展、曲折发展、恢复发展和波动回温四个历史发展时期,旅华客流年际变化呈现明显波动—强力波动—趋于和缓的变化特征,年内月季分布集中性较强,主要集中于一年中的3月~5月和9月~11月;空间上,泰国旅华游客在我国地域分布较为集中且相对稳定,旅游客流主要流向云南、广东、浙江、江苏、四川等省区和北京、上海、广州、昆明、成都等热点旅游城市。在此基础上,提出进一步拓展泰国旅华客源市场的相关策略。

关键词：旅华市场时空结构拓展策略泰国

Phenolic Compounds from Roots of Imperata cylindrica ***

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Chinese Herbal Medicines 2013年第3期5卷 240-243页

作者： LIU Rong-hua CHEN Shi-sheng REN gang SHAO feng HUANG Hui-lian Key Laboratory of Modern Preparation of Traditional Chinese Medicine Ministry of EducationJiangxi University of Traditional Chinese Medicine College of Pharmacy Jiangxi University of Traditional Chinese Medicine Zhejiang Research Institute of Traditional Chinese Medicine Co. Ltd.

Objective To study the chemical constituents from the roots of Imperata cylindrica *** The chemical constituents were isolated and purified by combination of silica gel,Sephadex LH-20,polyamide,and ODS column *** structures of the isolated compounds were identified by means of spectral data and physicochemical *** Twelve phenolic compounds were isolated from *** *** and identified as 4,7-dimethoxy-5-methylcoumarin(1),7-hydroxy-4-methoxy-5-methylcoumarin(2),7-O-β-D-glucopyranosyl-4-methoxy-5-methylcoumarin(3),6-hydroxy-5-methoxyflavone(4),5-methoxyflavone(5),5,7-dihydroxy-8-methoxyflavone(6),4-hydroxybenzaldehyde(7),4-hydroxy-cinnamic acid(8),4-hydroxy-3-methoxybenzoic acid(9),3,4-dimethoxyphenyl-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside(10),impecyloside(11),and graminone A(12).Conclusion Compounds 2—4,6,and 10 are obtained from this plant for the first time.

关键词： flavonoids Gramineae Imperata cylindrica var.major phenylpropanoids phenols

Correlations between low thyroid function and incidence of atrial fibrillation in hypertrophic obstructive cardiomyopathy

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Chronic Diseases and Translational Medicine 2020年第1期6卷 35-45页

作者： Liu Li-Min Shen Li-Shui Liu Shang-Yu Tu Bin Li Guo-Liang Hu feng Hu Zhi-Cheng Wu Ling-Min Fan Xiao-Han Zheng Li-Hui Ding Li-gang Yao Yan Department of Cardiovascular Medicine Clinical EP Lab&Arrhythmia CenterFuwai HospitalState Key Laboratory of Cardiovascular DiseaseNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China Department of Cardiovascular Medicine First Affiliated Hospital of Xi'an Jiaotong UniversityXi'anShaanxi 710061China

Background::Atrial fibrillation (AF) is the most common arrhythmia in patients with hypertrophic obstructive cardiomyopathy (HOCM). Data regarding the correlations of thyroid dysfunction and the incidence of AF in HOCM are quite limited. This study aimed to reveal the correlations between different thyroid status and the corresponding incidence of AF in a large HOCM ***::A total of 806 HOCM patients with complete information on thyroid function tests and comprehensive cardiac evaluations were recruited. The participants were divided into the AF group (n = 159) and non-AF group (n = 647) according to established medical history and results of Holter monitoring. The thyroid status of the study population and the corresponding incidence of AF were assessed and ***::Hypothyroidism accounted for the greatest proportion of thyroid dysfunction in HOCM patients. The incidence of AF significantly increased in individuals with both overt ( P = 0.022) and subclinical ( P = 0.007) hypothyroidism. Compared with participants in the non-AF group, those with positive AF episodes presented with lower free triiodothyronine (FT3) (2.86 ± 0.52 pg/mL vs. 3.01 ± 0.42 pg/mL, P = 0.001), higher free thyroxine (FT4) (1.24 ± 0.25 ng/dL vs. 1.15 ± 0.16 ng/dL, P < 0.001), and remarkably increased levels of thyrotropin (TSH) (12.6% vs. 5.3%, P = 0.001). Multivariable analyses demonstrated that the concentrations of FT3 (odds ratio [OR] = 0.470, 95% confidence interval [CI]: 0.272-0.813, P = 0.007) and FT4 (OR = 17.992, 95% CI: 5.750-56.296, P < 0.001), as well as TSH levels above normal ranges (OR = 2.276, 95% CI: 1.113-4.652, P = 0.024) were independently associated with the occurrence of AF in the large HOCM cohort. Conclusions::This study indicated a strong link between low thyroid function and the presence of AF in HOCM. Hypothyroidism (both overt and subclinical states) seems to be valuable for assessing the incidence of AF in patients with HOCM.

关键词： Atrial fibrillation Hypertrophic obstructive cardiomyopathy Hypothyroidism Thyroid hormone

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基于热平衡模型的镍铁电炉功率在线优化控制

中国有色冶金 2022年第3期51卷 60-65页

作者：李刚徐小锋中国恩菲工程技术有限公司北京100083

目前,电炉功率设定大都由操作人员根据经验和现场运行情况人为确定,受人为的经验和操作等影响较大,难以保证功率给定的实时最优性,从而影响生产指标。本文针对回转窑-电炉镍铁冶炼工艺(RKEF工艺)熔炼电炉,提出一种在线控制电炉功率的优... 详细信息

目前,电炉功率设定大都由操作人员根据经验和现场运行情况人为确定,受人为的经验和操作等影响较大,难以保证功率给定的实时最优性,从而影响生产指标。本文针对回转窑-电炉镍铁冶炼工艺(RKEF工艺)熔炼电炉,提出一种在线控制电炉功率的优化方法。该方法通过建立电炉热平衡模型,对电炉进料、烟气和炉体冷却系统相关过程变量进行在线检测,实现电极功率最优设定值的在线计算;通过构建BP神经网络误差模型,利用出渣周期实测数据生成数据样本对网络模型进行训练和更新,实现对热平衡计算误差的预测和在线修正,提高热量计算的准确性和适应性。本文还基于工程数据采用仿真试验验证了该方法的有效性,指出该控制系统可以解决镍铁电炉智能冶炼的核心问题,下一步还需与其他子系统结合,形成完整智能冶炼厂解决方案。

关键词：镍铁冶炼电炉熔炼功率控制热平衡在线优化控制在线修正仿真验证智能冶炼

基于仿真的空地导弹武器体系作战效能评估决策方法

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控制与决策 2009年第10期24卷 1576-1579页

作者：郭继峰殷志宏崔乃刚哈尔滨工业大学航天工程系哈尔滨150001 北京机电工程研究所北京100074

首先,采用任务完成量度、工作时间度量和代价度量方法,设计了空地导弹武器体系的4个层次的作战效能评价指标;然后,建立射前阶段、突防阶段和毁伤阶段的数学模型,完成了对体系对抗过程的数学描述;同时,提出了效能品质的概念,采用风险场... 详细信息

首先,采用任务完成量度、工作时间度量和代价度量方法,设计了空地导弹武器体系的4个层次的作战效能评价指标;然后,建立射前阶段、突防阶段和毁伤阶段的数学模型,完成了对体系对抗过程的数学描述;同时,提出了效能品质的概念,采用风险场描述了空地导弹突防阶段的攻防对抗过程;最后,提供了效能指标的数学表达,形成了完整的空地导弹武器体系作战效能评估方法,并应用均匀设计方法设计了仿真方案,仿真结果表明了该方法的有效性.

关键词：风险场均匀设计攻防对抗作战效能导弹武器体系