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Search Results: 1 - 10 of 112144 matches for " 吴绍飞 "
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基于DWT-FastICA和IMPSCO的时变结构损伤识别研究
思瑶,
福州大学学报(自然科学版) , 2013,
Abstract: 提出了一种基于DWT-FastICA和IMPSCO的两阶段时变结构损伤识别方法. 第I阶段:首先,通过离散小波变换(discrete wavelet transform, DWT)对各传感器采集到的结构动力响应信号进行预处理;然后,利用快速独立分量分析(fast independent component analysis, FastICA)提取出包含损伤信息的特征分量,从而确定损伤发生的时刻并初步定位损伤.第II阶段:采用改进的多粒子群协同优化算法(improved multi-particle swarms cooperative optimization, IMPSCO)分时段进行物理参数优化,实现损伤的精确定位和定量.通过一个数值算例和试验验证了所提方法的有效性,同时从噪声水平和损伤大小两个方面对该方法进行了探讨.研究表明,所提的方法能够较好地应用于线性时变结构损伤发生时间、位置与损伤程度的识别,根据不同的需求,不仅能够实现快速的损伤初步定位,而且可以进一步对损伤进行精确定位和定量,具有良好的容噪性、鲁棒性和工程实用性.
考虑ssi的钢管混凝土框架结构易损性分析
,陈强,兆旗
武汉理工大学学报 , 2010,
Abstract: ?为了深入研究土?结构相互作用(ssi)对钢管混凝土框架抗震易损性能的影响,采用弹簧?阻尼单元模拟地基土,建立了考虑ssi与刚接情况下4层钢管混凝土框架结构体系有限元分析模型,进行了模态分析、地震响应与地震易损性分析。建立了不同结构体系在不同场地、不同强度等级地震作用下的结构损伤变形与损伤超越概率的关系曲线。
利用信号延展度度量的形态滤波算法
徐腊梅,,
武汉大学学报(信息科学版) , 2013,
Abstract: ?分析了传统形态滤波器的局限性,提出了一种建立在图像连通分量的延展度度量上、基于轮廓结构元素的新型cs形态滤波器。定义了一个基于轮廓结构元素的形态学击中运算,cs形态滤波器使用这一运算来提取噪声区域,一次性地将噪声区域内的噪声全部去除。实验结果表明,该滤波算法不仅具有很好的抗噪性,而且在保护图像细节方面的能力尤为突出。
基于多目标模糊决策的水量水质联合调度方案选择
Plans Selection of Water Quantity and Quality Joint Operation Based on Multi Objective Fuzzy Decision Making Method
 [PDF]

, 张翔, 邓志民, 李良, 阮燕云
Journal of Water Resources Research (JWRR) , 2012, DOI: 10.12677/JWRR.2012.14033
Abstract: 针对淮河流域水量水质联合调度风险分析问题中的多方案的选择问题,综合考虑两个主要污染物指标高锰酸盐指数指标和氨氮指数指标,分别建立水量水质联合调度BP神经网络高锰酸盐指数模拟模型和氨氮模拟模型,求得上诉两个指标的超标风险率;然后采用多目标模糊决策方法,分别以上述两个指标作为模糊决策的决策目标,以模拟的6个调度方案为模糊决策的决策方案,得到了由6个方案,2个目标组成的目标特征值矩阵,在此基础上建立模糊决策模型,得到了综合考虑高锰酸盐指数指标和氨氮指数指标两个水质指标的决策方案结果,计算得到了方案集相对优等决策的相对隶属度矩阵。结果表明,各决策方案的优劣次序为(324516),认为调度方案3风险率最小,为最优方案。
In plans selection of risk analysis of water quantity and quality joint operation in Huaihe River Basin, the BP neutral network simulation models of water quantity and quality joint operation of CODMn and NH3-N, the two main pollutants in Huaihe River Basin, are established to make out the risk rates of both of the two water indexes above. By the method of multi objective fuzzy decision making, The eigenvalues matrix is worked out, which consists of 6 simulated plans as the scheme, and those 2 indexes as the objects, Then the fuzzy decision making model is
梁柱端板连接节点初始转动刚度计算模型
兆旗,张素梅,
工程力学 , 2009,
Abstract: 应用组件法建立了端板连接节点初始转动刚度计算模型,考虑了端板受弯、柱翼缘受弯、螺栓受拉、柱子腹板受剪、柱子腹板受压和柱子腹板受拉变形对连接节点转动刚度的影响。基于板壳理论计算端板和柱子翼缘的弯曲变形,给出了不同加劲肋设置情况下的刚度计算公式;根据有限元分析结果,把柱子腹板受压刚度计算采用的有效宽度和EC3建议的承载力计算有效宽度统一;在计算螺栓刚度时,考虑了因螺栓预拉所挤紧的周围板件对螺栓变形的影响。该文模型和试验结果及已有模型进行对比,表明该计算模型不仅能精确计算节点的转动刚度,且相对于现有的分析模型更为简便、准确,便于实际工程中应用。
基于易损性分析的桁架桥传感器布设方法
,杨博,兆旗
工程力学 , 2010,
Abstract: 灾害或材料性能的退化其结构使用功能下降,为了有效地管理大型复杂结构并减少灾害的损失,结构健康监测系统的研发成为目前国际社会研究的热点。传感器的布设不仅决定着监测系统性能的好坏而且还影响着系统的造价与维护成本。该文从传感器布设的常用方法入手,提出了一种基于结构易损性分析的传感器布设方法。它基于构件刚度的重要性系数,通过其与冗余度的关系来搜索、确定结构的失效模式,并提出采用结构应变能来评价失效模式的损伤需求,进而确定最易损结构失效路径,据此布置传感器。最后通过一个桁架桥算例验证了该方法的可行性和有效性。研究发现,所提出的方法是可行的、有效的。
基于性能的RC框架结构现浇板式楼梯抗震性能评估
Component-performance-based seismic assessment of reinforced concrete plate stairs in existing frameworks

兆旗,李晨亮,
福州大学学报(自然科学版) , 2018, DOI: 10.7631/issn.1000-2243.16475
Abstract: 根据已有楼梯抗震试验结果,给出梯段板抗震性能水平及其量化指标;建立框架结构层间位移角与梯段板抗震性能指标之间的关系,并进行楼梯抗震性能宏观评价;基于梯段板、梯柱、与休息平台直接相连的框架柱等楼梯构件,给出既有RC框架结构板式楼梯抗震性能评估的具体方法和步骤.
Based upon the seismic performance test results of the staircases,this paper managed to determine the seismic performance levels and quantitative indicators of plate stairs,set up the relationship between the interlayer displacement angle of frame structures and seismic performance indicators of plate stairs,and conduct the macroscopic evaluation of seismic behavior of stairs in according with the framework performance level specified by the code. A method and process of evaluating the seismic the seismic performance of the existing stairs of the RC frame structure were also proposed on account of the performance of components,i.e. stair plates,staircase columns,the structural columns connected with rest platform,and etc
独塔部分斜拉桥顺桥向地面运动作用下的易损性分析
Seismic fragility analysis on extra-dosed PC bridge with single-tower under the motion of longitudinal bridge direction

少峰,上官萍,
福州大学学报(自然科学版) , 2017, DOI: 10.7631/issn.1000-2243.2017.02.159
Abstract: 以墩塔梁固结的独塔预应力混凝土部分斜拉桥为对象,采用动力增量法和数据统计分析研究该类桥梁的地震易损性,确定顺桥向地面运动作用下结构构件的易损部位及损伤破坏概率. 采用理论易损性分析方法,选取地面峰值加速度作为地震输入强度指标,并以放大系数为基础选取地震输入;以位移延性比、强度与变形、相对位移、索力为指标分别定义了各构件的损伤状态;根据各构件的损伤概率,拟合建立了各构件及全桥的易损性曲线. 结果表明,在顺桥向地面运动作用下,中墩和支座为最易损构件;边墩、主梁均会发生不同程度的损伤;斜拉索、桥塔、桩基安全储备较高.
The PC cable-stayed bridge with a single tower rigidly connected with the girder was selected as the object of the research. The dynamic increment method and data statistical analysis method were used to study the seismic vulnerability for bridge of this kind. The vulnerable elements and the corresponding damage probability were ensured under the ground motion in longitudinal bridge direction. The peak acceleration of ground motion was chosen as the intensity index input of the earthquake records with the use of vulnerability analysis theory and earthquake input was selected by the amplification coefficient. Damage status for each component was defined with the index of displacement ductility ratio,strength and deformation,relative displacement and the cable force. The vulnerability curve for the component and the whole bridge were established based on the damage probability. Results shows that the middle pier and the bearing were the most vulnerable part under the ground motion in longitudinal bridge direction,the side pier and the girder showed a damage at different degree and the cables,bridge tower and the piles showed a high safety storage
不同硒肥类型对毛葡萄果实硒含量及品质的影响初探
Effects of Different Selenium Fertilizer on Selenium Content and Quality of Vitis quinquangularis Rehd.
 [PDF]

代东, 艳艳, 黄永才, 黄伟华, 刘洁云, 牟海,, 黄雁, 李乃流, 刘永贤, 姚宁
Hans Journal of Agricultural Sciences (HJAS) , 2016, DOI: 10.12677/HJAS.2016.66023
Abstract:
为开展广西地区毛葡萄富硒研究,本试验通过采用“聚福硒”、“泰山葡萄专用补硒叶面肥”、“中农6号”、“康熙宝有机水溶肥料”四种常见硒叶面肥,研究其对毛葡萄富硒效果及品质影响。结果表明:四种硒肥富硒效果表现为“聚福” > “中农” > “康熙” > “泰山”,与对照(CK)相比分别提高了96.08%,85.56%,71.12%,54.11%;不同类型硒肥对毛葡萄果实总酸、维生素C、总糖影响不尽相同;总糖含量仅“康熙”处理比对照增加0.89%,其余三种处理却比对照低;维生素C含量除“中农”比对照低其余均显著增高;总酸含量“聚福”和“中农”分别比对照显著增加13.21%和18.22%,而“泰山”和“康熙”与对照相当但差异不显著。综合各种因素考虑,我们认为“康熙宝”牌硒肥为本次试验最佳肥类。
In order to carry out the research on the Se-rich of Vitis quinquangularis Rehd. in Guangxi, this test used four selenium fertilizers of “Jufuxi”, “Taishan special selenium supplement foliar fertilizer for grape”, “Zhongnong No. 6”, “Kangxibao organic water soluble fertilizer” to study the effects on grape quality and selenium content. The results showed that: the selenium enriched effect of the four selenium fertilizers was “Jufu” > “Zhongnong” > “Kangxi” > “Taishan”, increased by 96.08%, 85.56%, 71.12% and 54.11% respectively compared to the control (CK); the effects of different selenium fertilizers on total acid, vitamin C and total sugar were different; the total sugar content of the “Kangxi” treatment was higher than the control by 0.89%, while the remaining three treatments were all lower; all treatments except “Zhongnong” had significantly increase than the control on the vitamin C content; the total acid content of “Jufu” and “Zhongnong” was higher than the control by 18.22% and 13.21%, but “Taishan” and “Kangxi” showed little differences to the control. We think that the selenium fertilizer of “Kangxi Bao” brand was the best fertilizer in this test.
FRP-PVC管约束圆形截面钢筋混凝土组合柱滞回性能试验研究
,智林,兆旗,俞波
建筑结构学报 , 2014,
Abstract: 6个FRP-PVC管约束圆形截面钢筋混凝土组合柱试件进行滞回性能试验,研究轴压比n、FRP横向包裹层数m和FRP类型对组合柱在低周往复荷载作用下的破坏模式、滞回特性、位移延性、能量耗散能力、承载力退化、刚度退化等性能的影响。试验结果表明,当外包FRP-PVC管开裂并退出工作时,试件承载力呈跳跃式下降,试件退化为钢筋混凝土柱,可将外包FRP-PVC管的开裂作为该类构件即将破坏的首次预警;所有试件的滞回曲线均较为饱满,捏缩现象不明显,滞回性能良好;试件的承载力退化不显著;轴压比的增大提高了试件的峰值荷载,同时延缓了刚度退化趋势,降低了试件的耗能能力;与BFRP包裹的试件相比,CFRP包裹试件的峰值荷载、耗能能力有所提高,刚度退化延缓;BFRP包裹层数的增加可以延缓试件刚度退化并提高其延性。
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