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时滞微生物连续培养动力系统稳定性收敛速度的研究
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作者 张春普 翟延慧 《生物数学学报》 2019年第1期40-46,共7页
讨论了具有时滞微生物连续培养动力系统的稳定性和α-稳定性.应用时滞系统稳定性切换几何判据法研究了系统的线性稳定性和α-稳定性,并比较这两个稳定性的区别与联系.最后应用数值模拟验证结论的准确性和有效性.
关键词 微生物连续培养模 时滞 稳定性 α-稳定性 时滞系统稳定性切换几何判据法
自锚式钢箱梁悬索桥静力稳定性分析 预览
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作者 王春江 戴建国 +1 位作者 臧瑜 肖华裕 《桥梁建设》 EI CSCD 北大核心 2019年第2期47-51,共5页
为了解自锚式钢箱梁悬索桥的整体失稳模态和钢箱加劲梁的局部稳定性,以重庆鹅公岩轨道专用桥(主跨600 m自锚式钢箱梁悬索桥)为背景,采用Abaqus软件建立全桥多尺度有限元模型(跨中段钢箱梁建立局部精细模型),采用弧长法进行非线性静力稳... 为了解自锚式钢箱梁悬索桥的整体失稳模态和钢箱加劲梁的局部稳定性,以重庆鹅公岩轨道专用桥(主跨600 m自锚式钢箱梁悬索桥)为背景,采用Abaqus软件建立全桥多尺度有限元模型(跨中段钢箱梁建立局部精细模型),采用弧长法进行非线性静力稳定承载力分析,研究该桥的整体稳定和局部稳定问题及其相互影响规律。结果表明:达到整体稳定极限荷载时,该桥跨中段钢箱梁发生明显的竖向和横向变形,全桥静力稳定极限状态由钢箱梁的整体稳定控制;整体稳定极限状态下,跨中段钢箱梁主要板件不会发生局部屈曲,中腹板局部发生屈服,其余板件仍处在弹性阶段,中腹板是钢箱梁局部稳定的控制部件。 展开更多
关键词 自锚式悬索桥 钢箱梁 稳定性 整体稳定 局部稳定 多尺度模型 有限元法
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统计数据中的"稳中有变、变中有忧"--2019年上半年经济运行情况分析
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作者 许宪春 许亚婷 《经济学动态》 CSSCI 北大核心 2019年第9期18-25,共8页
2018年底召开的中央经济工作会议和2019年政府工作报告都充分肯定了过去一年经济工作取得的重大成绩,都对中国经济运行做出了“稳中有变、变中有忧”的重要判断。本文运用统计数据从经济增长、就业、物价、居民收入、居民消费等方面阐... 2018年底召开的中央经济工作会议和2019年政府工作报告都充分肯定了过去一年经济工作取得的重大成绩,都对中国经济运行做出了“稳中有变、变中有忧”的重要判断。本文运用统计数据从经济增长、就业、物价、居民收入、居民消费等方面阐述了经济运行总体平稳;从新经济新动能快速增长、经济结构继续改善、供给侧结构性改革重点任务成果巩固等方面阐述了经济运行稳中有进;从新动能仍然不足,美欧经济增速回落和中美贸易摩擦持续将会对外需产生向下压力,基础设施投资、民间投资和房地产开发投资增速存在下行压力,工业企业利润总额和一般公共预算收入增速存在回落压力等方面揭示经济运行“稳中有变、变中有忧”。初步判断,2019年下半年中国经济增速存在下行压力,但总体上仍将保持平稳运行的态势。 展开更多
关键词 统计数据 总体平稳 稳中有进 稳中有变 变中有忧
南京长江五桥主桥结构非线性稳定性研究 预览
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作者 吕梁 崔冰 +2 位作者 钟汉清 辜友平 郭志明 《桥梁建设》 EI CSCD 北大核心 2019年第4期40-45,共6页
南京长江五桥主桥为主跨600m的三塔组合梁斜拉桥,半飘浮体系。为研究该桥在施工和运营阶段的极限承载能力,采用ANSYS软件建立全桥有限元模型,考虑几何与材料非线性,计算施工全过程及主要运营阶段各工况下结构的非线性稳定系数,评估主要... 南京长江五桥主桥为主跨600m的三塔组合梁斜拉桥,半飘浮体系。为研究该桥在施工和运营阶段的极限承载能力,采用ANSYS软件建立全桥有限元模型,考虑几何与材料非线性,计算施工全过程及主要运营阶段各工况下结构的非线性稳定系数,评估主要构件的承载能力,并探讨桥塔钢壳与斜拉索破断对结构非线性稳定性的影响。结果表明:施工阶段及运营阶段,该桥的整体非线性稳定系数均大于临界值2.0,结构的稳定性能满足要求;三大受力构件中,主梁的承载能力最强,桥塔次之,斜拉索的承载能力相对最弱;桥塔钢壳对提升结构整体稳定性能具有不可忽略的作用;与考虑斜拉索破断时相比,不考虑斜拉索破断时结构的非线性稳定系数显著提高。 展开更多
关键词 斜拉桥 稳定性 施工阶段 运营阶段 非线性稳定系数 承载能力 有限元法
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氯化钯实验评价化学镀镍溶液稳定性的方法与优化 预览
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作者 赵涛 张德忠 毛祖国 《电镀与精饰》 CAS 北大核心 2019年第10期43-46,共4页
采用氯化钯实验方法评价化学镀镍溶液稳定性,研究了氯化钯在三种含Cl^-体系中溶解情况,优化氯化钯溶液配制方法。对比了时间法、体积法和升温法三种方法的优缺点,优选出时间法并对其工艺参数进行优化。通过实验验证了新方法的精密度和... 采用氯化钯实验方法评价化学镀镍溶液稳定性,研究了氯化钯在三种含Cl^-体系中溶解情况,优化氯化钯溶液配制方法。对比了时间法、体积法和升温法三种方法的优缺点,优选出时间法并对其工艺参数进行优化。通过实验验证了新方法的精密度和准确性。结果表明,采用氯化铵体系溶解氯化钯,以时间法作为实验方法,并将实验温度升高为“镀液最佳工作温度”更能准确体现镀液稳定性,提高实验效率。实验证明改进后的氯化钯实验方法具有较高的精密度和准确度。 展开更多
关键词 化学镀 稳定性 氯化钯 稳定系数
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舰船稳性与破损稳性要求
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作者 夏齐强 朱韬 朱军 《船舶工程》 CSCD 北大核心 2019年第6期30-35,共6页
综合分析国内外有关舰船稳性与破损稳性的标准和规范,详细分析国际海事组织《海上人命安全公约》(SOLAS 2004)、美国海军水面舰船稳性与浮性标准(DDS 079-1)和舰船通用规范(GJB4000—2000)对稳性的要求。采用数值计算方法计算某船的完... 综合分析国内外有关舰船稳性与破损稳性的标准和规范,详细分析国际海事组织《海上人命安全公约》(SOLAS 2004)、美国海军水面舰船稳性与浮性标准(DDS 079-1)和舰船通用规范(GJB4000—2000)对稳性的要求。采用数值计算方法计算某船的完整稳性和破损稳性,系统分析舰船稳性与破损稳性指标要素。结果表明:美国海军水面舰船稳性衡准、国际海事组织的破损稳性标准和舰船通用规范对稳性与破损稳性有其相对独立的指标体系及要求;美国海军水面舰船稳性与浮性标准对舰船稳性与破损稳性的个别指标的要求更为严格;我国规范的要求总体上较为合理,但缺乏对复原力臂特征值的衡量要求、对船舶破损之后抵抗风浪能力的要求和对可浸水线计算的要求。 展开更多
关键词 舰船 稳性 破损稳性 衡准
Drag Optimization of A Planing Vessel Based on the Stability Criteria Limits 预览
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作者 Yasin MASUMI Amir H. NIKSERESHT 《中国海洋工程:英文版》 SCIE EI CSCD 2019年第3期365-372,共8页
One of the important phases of designing a craft is stability analysis and optimization of the drag force in cruise speed. In this research the longitudinal and lateral stability of a planing hull craft (DTMB 62 model... One of the important phases of designing a craft is stability analysis and optimization of the drag force in cruise speed. In this research the longitudinal and lateral stability of a planing hull craft (DTMB 62 model 4667-1) is investigated with some semi-empirical formulae and the effects of some important design parameters are investigated on the limit of stability region. Also on the basis of these empirical formulations and by using a genetic algorithm the drag force is optimized in each constant cruise speed with the stability criteria limits at a constant beam or projected area. Aspect ratio, the longitudinal position of the gravity center and deadrise angle are the optimization parameters. The results show that the aspect ratio and the longitudinal position of the gravity center are two important parameters in optimizing the drag force and for this planing vessel the drag force can be reduced by 22%. 展开更多
关键词 longitudinal STABILITY TRANSVERSE STABILITY drag-optimization Savitsky FORMULA
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浅谈步枪射击运动的稳定性训练 预览
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作者 程超 《科教文汇》 2019年第12期129-130,共2页
步枪射击是一项准确性极高的运动项目,其特点是以自我为中心,在动中求静、静中求稳、稳中求准。因此,运动员稳定性在步枪射击比赛中起着决定性的作用。本文以阐述步枪运动员稳定性训练为核心,详细描述射击正确姿势、姿势应掌握的要点、... 步枪射击是一项准确性极高的运动项目,其特点是以自我为中心,在动中求静、静中求稳、稳中求准。因此,运动员稳定性在步枪射击比赛中起着决定性的作用。本文以阐述步枪运动员稳定性训练为核心,详细描述射击正确姿势、姿势应掌握的要点、运动员稳定性训练的基本项目以及心理稳定性训练等。笔者通过多年训练指导经验,浅谈步枪射击运动的稳定性训练,旨在为步枪运动培养提供参考。 展开更多
关键词 步枪射击 稳定性 姿势 训练的基本项目 心理稳定性
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Analysis of coal pillar stability(ACPS): A new generation of pillar design software 预览
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作者 Christopher Mark Zach Agioutantis 《矿业科学技术学报:英文版》 CSCD 2019年第1期87-91,共5页
Thirty years ago, the analysis of longwall pillar stability(ALPS) inaugurated a new era in coal pillar design.ALPS was the first empirical pillar design technique to consider the abutment loads that arise from full ex... Thirty years ago, the analysis of longwall pillar stability(ALPS) inaugurated a new era in coal pillar design.ALPS was the first empirical pillar design technique to consider the abutment loads that arise from full extraction, and the first to be calibrated using an extensive database of longwall mining case histories.ALPS was followed by the analysis of retreat mining stability(ARMPS) and the analysis of multiple seam stability(AMSS). These methods incorporated other innovations, including the coal mine roof rating(CMRR), the Mark-Bieniawski pillar strength formula, and the pressure arch loading model. They also built upon ever larger case history databases and employed more sophisticated statistical methods.Today, these empirical methods are used in nearly every underground coal mine in the US. However,the piecemeal manner in which these methods have evolved resulted in some weaknesses. For example,in certain situations, it may not be obvious which program is the best to use. Other times the results from the different programs are not entirely consistent with each other. The programs have also not been updated for several years, and some changes were necessary to keep pace with new developments in mining practice. The analysis of coal pillar stability(ACPS) now integrates all three of the older software packages into a single pillar design framework. ACPS also incorporates the latest research findings in the field of pillar design, including an expanded multiple seam case history data base and a new method to evaluate room and pillar panels containing multiple rows of pillars left in place during pillar recovery.ACPS also includes updated guidance and warnings for users and features upgraded help files and graphics. 展开更多
关键词 PILLAR design GROUND control STABILITY Empirical METHODS
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多端柔性直流输电系统的阻抗建模及稳定性分析
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作者 陈秀秀 杨兴武 +2 位作者 王楠楠 李豪 符杨 《水电能源科学》 北大核心 2019年第7期162-166,共5页
与两端柔性直流输电(VSC-HVDC)系统相比,多端柔性直流输电(VSC-MTDC)系统更具灵活性和经济性,且有助于电力系统接纳新能源,在VSC-MTDC系统中,换流器需兼备整流器和逆变器的功能,其控制器参数会对系统的稳定性造成较大的影响,阻抗分析法... 与两端柔性直流输电(VSC-HVDC)系统相比,多端柔性直流输电(VSC-MTDC)系统更具灵活性和经济性,且有助于电力系统接纳新能源,在VSC-MTDC系统中,换流器需兼备整流器和逆变器的功能,其控制器参数会对系统的稳定性造成较大的影响,阻抗分析法可直接用于指导控制器的参数整定。为此,以一个三端系统为例,提出了适用于VSC-MTDC系统的阻抗稳定性分析方法,建立了系统的等效小信号阻抗模型,根据Nyquist判据判稳,并结合时域仿真,对直流电压控制器参数进行了分析和整定。仿真分析结果验证了所提阻抗模型和判稳方法有效、精确。 展开更多
关键词 阻抗分析法 柔性直流输电 稳定性 Nyquist判据 PI控制参数
均质软土地基上土堤稳定性的极限分析方法
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作者 张惠敏 雷国辉 +1 位作者 刘芳雪 张飞 《岩土工程学报》 EI CAS CSCD 北大核心 2019年第A02期21-24,共4页
为评估均质软土地基上土堤的稳定性,假设地基土体沿圆弧形滑动面破坏,不排水抗剪强度随深度线性增加,并假设土堤材料沿对数螺旋线形滑动面破坏,采用黏聚力和内摩擦角描述其抗剪强度,基于上限定理,建立了一种稳定性分析方法,用于计算得... 为评估均质软土地基上土堤的稳定性,假设地基土体沿圆弧形滑动面破坏,不排水抗剪强度随深度线性增加,并假设土堤材料沿对数螺旋线形滑动面破坏,采用黏聚力和内摩擦角描述其抗剪强度,基于上限定理,建立了一种稳定性分析方法,用于计算得到土堤的无量纲化的稳定数和稳定图,并确定土堤的最小安全系数和临界滑动面。采用本文方法对土堤失稳现场试验工程案例开展了计算分析,结果表明,所得到的最小安全系数与土堤的实测失稳条件吻合,最小安全系数与临界滑动面的计算结果也与变分极限平衡法和条分极限平衡法所得到的计算结果吻合良好。 展开更多
关键词 均质软土地基 土堤 稳定性 极限分析 稳定数
Active splitting strategy searching approach based on MISOCP with consideration of power island stability 预览
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作者 Yifan ZHOU Wei HU +1 位作者 Yong MIN Le ZHENG 《现代电力系统与清洁能源学报(英文)》 CSCD 2019年第3期475-490,共16页
Active splitting control utilizes real-time decision and system-level splitting to prevent cascading blackouts and to maintain power supply under severe disturbances. Splitting strategy searching(SSS) is one of the mo... Active splitting control utilizes real-time decision and system-level splitting to prevent cascading blackouts and to maintain power supply under severe disturbances. Splitting strategy searching(SSS) is one of the most crucial issues in active splitting control for deciding‘‘where to split’’. SSS determines the splitting surface in real time to properly divide the asynchronous generators into isolated islands with an optimal control effect. In this paper, an SSS approach that focuses on island stability is presented. The proposed SSS approach is designed to ensure a rational stability margin and regulation ability on each island during and after the transient process of system splitting. This method includes the active/reactive power flow feasibility constraints and voltage/angle stability constraints in the steady state as well as the frequencyresponse capability constraints in the transient process. By considering the island stability constraints in the SSS, the proposed approach can avoid the splitting strategies with poor stability performance. Therefore, the major advantage of the proposed approach is that it can ensure better island static and transient stability during and after the splitting control. In addition, the entire model is formulated as a mixed-integer second-order cone programming(MISOCP)model. Thus, it can be rapidly solved by using commercial optimization solvers. Numerical simulations of a realistic provincial power system in central China demonstrate thevalidity of the proposed approach and the necessity of considering the island stability issues. 展开更多
关键词 SPLITTING STRATEGY searching(SSS) MIXED-INTEGER second-order cone programming(MISOCP) Controlled ISLANDING Static STABILITY margin Transient STABILITY POWER system
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Capsizing Probability of Dead Ship Stability in Beam Wind and Wave for Damaged Ship 预览
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作者 HU Li-fen ZHANG Ke-zheng +1 位作者 LI Xiao-ying CHANG Run-xin 《中国海洋工程:英文版》 SCIE EI CSCD 2019年第2期245-251,共7页
The International Maritime Organization has developed the second-generation intact stability criteria. Thus, damage stability criteria can be established in the future. In order to identity the capsizing probability o... The International Maritime Organization has developed the second-generation intact stability criteria. Thus, damage stability criteria can be established in the future. In order to identity the capsizing probability of damaged ship under dead ship condition, this paper investigates two methods that can be used to research the capsizing probability in time domain, which mainly focus on the nonlinear righting lever GZ curve solution. One method subjects the influence of damaged tanks on the hull shape down to the wind and wave, and the other method is consistent with the real-time calculation of the GZ curve. On the basis of one degree of freedom rolling equation, the solution is Monte Carlo method, and a damaged fishery bureau vessel is taken as a sample ship. In addition, the results of the time-domain capsizing probability under different loading conditions are compared and analyzed. The relation of GM and heeling angle with the capsizing probability is investigated, and its possible reason is analyzed. On the basis of combining the time-domain flooding process with the capsizing probability calculation, this research aims to lay the foundation for the study of capsizing probability in time domain under dead ship condition, as well as provide technical support for capsizing mechanism of dead ship stability and damage stability criteria establishment in waves. 展开更多
关键词 damage STABILITY criteria DEAD SHIP STABILITY capsizing PROBABILITY FLOODING process time domain
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Hybrid Laser Ablation and Chemical Modification for Fast Fabrication of Bio-inspired Super-hydrophobic Surface with Excellent Self-cleaning,Stability and Corrosion Resistance
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作者 Zhen Yang Xianping Liu Yanling Tian 《仿生工程学报:英文版》 SCIE EI CSCD 2019年第1期13-26,共14页
Although laser ablation is considered as a facile technique to fabricate bio-inspired super-hydrophobic surfaces,the issue is that the initial laser treated metallic surfaces show super-hydrophilic property.It will ta... Although laser ablation is considered as a facile technique to fabricate bio-inspired super-hydrophobic surfaces,the issue is that the initial laser treated metallic surfaces show super-hydrophilic property.It will take a long period to reach super-hydrophobic state under ambient air.It is reported that these super-hydrophobic surfaces could be easily damaged by thermal heating effect or interaction with other liquids,causing uncontrolled loss of super-hydrophobicity.In this study,a stable super-hydrophobic aluminum surface was rapidly fab-ricated via the hybrid laser ablation and surface chemical modification of(heptadecafluoro-1,1,2,2-tetradecyl)triethoxysilane(AC-FAS).Surface morphology and chemistry were systematically investigated to explore the generation mechanism of super-hydrophobicity.The water contact angle of the treated surfaces can reach up to 160.6°±1.5°with rolling angle of 3.0°±1.0°,exhibiting perfect self-cleaning capability,long-term stability,and excellent chemical stability in acidic as well as alkaline solutions.The potentiodynamic polarization tests implied that the super-hydrophobic surfaces showed better anti-corrosion performance.This hybrid laser ablation and surface chemical modification are very time-saving and low-cost,which offers a rapid way for quantity production of super-hydrophobic surface on aluminum material. 展开更多
关键词 bioinspiration nanosecond laser SUPER-HYDROPHOBIC chemical STABILITY corrosion resistance SELF-CLEANING long-term STABILITY
适型分数阶非线性系统的输入到状态稳定分析 预览
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作者 唐莉 高扬 《大庆师范学院学报》 2019年第3期69-72,共4页
基于非线性系统输入到状态稳定理论,在适型分数阶导数意义下,针对导数阶数在0到1开区间的分数阶非线性系统,给出输入到状态稳定定义,进而建立非线性系统实现输入到状态稳定的Lyapunov定理。
关键词 非线性系统 分数阶 Lyapunov定理 指数稳定
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考虑心理因素和饱和治疗的H7N9禽流感动力学模型分析 预览
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作者 郭树敏 Mini GHOSH 《上海师范大学学报:自然科学版》 2019年第3期327-337,共11页
研究了一种带治疗的病媒传播疾病的流行模型.得到了模型的基本再生数R0,模型的平衡点和阈值由R0确定.利用Bendixson-Dulac定理,证明了当R0>1时,该模型的唯一正平衡点是全局稳定的.该结果可以帮助探索控制媒介传染病传播的方法.最后... 研究了一种带治疗的病媒传播疾病的流行模型.得到了模型的基本再生数R0,模型的平衡点和阈值由R0确定.利用Bendixson-Dulac定理,证明了当R0>1时,该模型的唯一正平衡点是全局稳定的.该结果可以帮助探索控制媒介传染病传播的方法.最后对模型进行了数值模拟,验证了该结论. 展开更多
关键词 媒介传染病 数学模型 稳定性 控制措施
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Slope Stability Analyses of Outang Landslide Based on the Peak and Residual Shear Strength Behavior 预览
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作者 YANG Xiuhan VANAPALLI Sai 《工程科学与技术》 EI CAS CSCD 北大核心 2019年第4期55-68,共14页
Most of the natural and compacted fine-grained soil slopes that are in saturated or unsaturated condition undergo a large deformation prior to reaching failure conditions.Such slopes should be designed taking account ... Most of the natural and compacted fine-grained soil slopes that are in saturated or unsaturated condition undergo a large deformation prior to reaching failure conditions.Such slopes should be designed taking account of their strain-softening behavior using the residual shear strength (RSS) parameters.In this paper,the slope stability of a recently reactivated Outang landslide near the Three Gorges Dam in China is analyzed based on the RSS parameters of unsaturated soils.In addition,comparisons are provided in the FOS values of slope using both the peak shear strength (PSS) and RSS parameters.Firstly,a series of site investigations of the hydrologic and geologic conditions,ground surface displacements and cracks were described.The PSS and RSS behaviors of the sliding soils derived from a series of direct shear test results performed on saturated and unsaturated soil specimens are summarized.Secondly,a series of slope stability analysis were conducted considering the precipitation and Yangtze River water level variation within a representative period of 7 months,based on the PSS and the RSS properties.In this study,three different scenarios were considered,which include: i) considering only the precipitation with a constant water level;ii) considering only the decrease in water level without rainfall;iii) considering the combination of precipitation and decrease in water level.In each scenario,four steps were included to calculate the values of factor of safety (FOS) at different times.1) A steady-state seepage analysis was conducted with a constant total head at 525 m on the left boundary and 175 m on the slope surface below the Yangtze River water level.The initial pore water pressures were simulated in the slope under no precipitation and variation of water level.2) A specific boundary condition was applied on the slope surface to model the precipitation and Yangtze River water level variation.A transient seepage analysis was conducted to calculate pore water pressures at different times based on the initial po 展开更多
关键词 UNSATURATED soil LANDSLIDE REACTIVATION RESIDUAL shear strength SLOPE stability analysis
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地铁供电系统继电保护探究 预览
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作者 艾毅 《电力系统装备》 2019年第12期5-6,共2页
城市地铁的修建极大地缓解了交通拥堵状况,地铁成为城市交通未来主要的一个发展趋势。地铁当中的供电网结构相对来说比较复杂,对于继电保护装置的要求相对来说更加严格,需要不断地将地铁供电系统的继电保护装置进行优化。
关键词 地铁供电系统 继电保护配置 稳定性
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An Assessment of ENSO Stability in CAMS Climate System Model Simulations
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作者 Lijuan HUA Lin CHEN +3 位作者 Xinyao RONG Jian LI Guo ZHANG Lu WANG 《气象学报:英文版》 SCIE CSCD 2019年第1期80-88,共9页
We present an overview of the El Ni?o–Southern Oscillation(ENSO) stability simulation using the Chinese Academy of Meteorological Sciences climate system model(CAMS-CSM). The ENSO stability was quantified based on th... We present an overview of the El Ni?o–Southern Oscillation(ENSO) stability simulation using the Chinese Academy of Meteorological Sciences climate system model(CAMS-CSM). The ENSO stability was quantified based on the Bjerknes(BJ) stability index. Generally speaking, CAMS-CSM has the capacity of reasonably representing the BJ index and ENSO-related air–sea feedback processes. The major simulation biases exist in the underestimated thermodynamic damping and thermocline feedbacks. Further diagnostic analysis reveals that the underestimated thermodynamic feedback is due to the underestimation of the shortwave radiation feedback, which arises from the cold bias in mean sea surface temperature(SST) over central–eastern equatorial Pacific(CEEP). The underestimated thermocline feedback is attributed to the weakened mean upwelling and weakened wind–SST feedback(μ_a) in the model simulation compared to observation. We found that the weakened μ_a is also due to the cold mean SST over the CEEP.The study highlights the essential role of reasonably representing the climatological mean state in ENSO simulations. 展开更多
关键词 coupled general CIRCULATION model(CGCM) Bjerknes(BJ) STABILITY index air–sea FEEDBACK
60Co-γ辐照前后姜黄HPLC指纹图谱和姜黄素含量变化研究
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作者 黄萌萌 马振中 +3 位作者 刘聪燕 刘玉萍 瞿鼎 陈彦 《中草药》 CAS CSCD 北大核心 2019年第8期1972-1978,共7页
目的测定姜黄饮片中姜黄素的含量,并建立姜黄的HPLC指纹图谱,评价60Co-γ辐照对姜黄化学成分的影响。方法对60Co-γ辐照前后13批次姜黄饮片粉末中姜黄素含量进行测定;建立姜黄饮片HPLC指纹图谱并对其方法学进行考察。采用配对样本t检验... 目的测定姜黄饮片中姜黄素的含量,并建立姜黄的HPLC指纹图谱,评价60Co-γ辐照对姜黄化学成分的影响。方法对60Co-γ辐照前后13批次姜黄饮片粉末中姜黄素含量进行测定;建立姜黄饮片HPLC指纹图谱并对其方法学进行考察。采用配对样本t检验和中药色谱指纹图谱相似度评价软件对辐照前后姜黄化学成分变化进行分析,结合聚类分析(HCA)和主成分分析(PCA)对辐照前、后样品进行综合评价,并对3批次姜黄样品辐照后3、6个月的稳定性进行了考察。结果 13批次姜黄粉末辐照前后姜黄素含量无统计学差异(P>0.05);姜黄HPLC指纹图谱确定了16个共有峰,各批次姜黄辐照前后指纹图谱的相似度均大于0.998;同批次辐照前与辐照后样品聚类一致性较好,3批次辐照前后姜黄样品放置3、6个月后与0个月相比姜黄素含量变化RSD<5%,指纹图谱相似度均大于0.95。结论 60Co-γ辐照对姜黄中姜黄素含量和整体化学成分一致性基本无影响,且不影响其稳定性,通过指纹图谱结合指标成分含量分析可以更好地评价60Co-γ辐照对姜黄化学成分的影响,为姜黄辐照灭菌方式的选择提供了实验依据。 展开更多
关键词 姜黄 60Co-γ辐照 姜黄素 指纹图谱 稳定性
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