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Search Results: 1 - 10 of 54158 matches for " 潘立登 "
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噁草酮和丙炔噁草酮对5种稻田杂草室内活性的比较
Bioactivity of Oxadiazon and Oxadiargyl to 5 Weeds of Rice Paddy
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钱忠海, ,, 张军民
Botanical Research (BR) , 2014, DOI: 10.12677/BR.2014.31004
Abstract: 采用土壤浇灌法和茎叶喷雾法在室内测定了噁草酮和丙炔噁草酮对稗草、千金子、鸭舌草、鳢肠和碎米莎草的生物活性。结果表明,用土壤浇灌法,噁草酮对千金子、鸭舌草、碎米莎草、稗草和鳢肠IC90分别为13.9823.4335.48247.58 561.78 g a.i./hm2;丙炔噁草酮对鸭舌草、碎米莎草、千金子、稗草和鳢肠IC90分别为15.5324.4228.0854.38 98.35 g a.i./hm2。用茎叶喷雾法,噁草酮对碎米莎草、鸭舌草、千金子、稗草和鳢肠IC90分别53.01111.57187.11342.75 and 425.34 g a.i./hm2;丙炔噁草酮对碎米莎草、千金子、鸭舌草、稗草和鳢肠IC90分别为14.8722.2122.6386.23 and 300.63 g a.i./hm2。测定结果表明丙炔噁草酮对供试
多变量多时滞非方系统的解耦内模控制
要艳静,王晶,
化工学报 , 2008,
Abstract: 多变量复杂控制系统不仅具有多耦合和多时滞性,还具有结构上的复杂性,即输入输出不等,传递函数为奇异矩阵。传统的多变量内模控制是基于对非奇异对象求逆来进行的,因此很难解决这类问题。针对该情况引入矩阵论中的广义逆概念,通过求对象的广义逆矩阵来设计解耦内模控制器,打破了内模控制只能对方系统进行控制的局限性,并利用泰勒近似很好地解决了多滞后的问题,最后通过设计特殊形式的滤波器,不仅能够消除由纯滞后近似引入的不稳定极点,保证系统的稳定性,且能够保证系统的正则性。仿真结果表明,该方法不仅跟踪迅速,且继承了内模控制的无余差和强鲁棒性,动态解耦效果良好,仅对时滞变化较为敏感。由于系统基于内模控制设计,故模型匹配度越高,系统响应越好。
丙烯水合反应器数学模型
,马俊英,谢成祥
化工学报 , 1995,
Abstract: 1引言异丙醇是一种重要的有机化工原料,目前工业生产多用丙烯气相直接水合法。对该类异丙醇生产装置的建模与操作条件的优化国内外未见文献报道。本文针对某化工厂的工业丙烯气相直接水合反应器装置,从反应动力学机理出发,结合生产数据,建立了该反应器的简化数学模型,为该反应器的操作条件在线优化提供了依据。2数学模型的建立
基于rbf神经网络的网格数据聚类方法
,郑应平,鸿,陈俊
计算机应用 , 2007,
Abstract: ?把径向基函数(rbf)神经网络和网格结合起来,提出了一种能够并行处理数据和便于增量计算的智能聚类方法。介绍了网格聚类原理、rbf神经网络神经元的数量和基函数的选择,并针对数据聚集区域的位置辨识、提高分辨率和计算速度等问题,深入讨论了聚类策略与聚类算法。仿真表明了该方法的有效性。
超长混凝土结构温度后浇带合理宽度的研究
Research on Rational Width of Post-Casting Temperature Band in Construction of Super-Long Reinforced Concrete Structures
 [PDF]


Hans Journal of Civil Engineering (HJCE) , 2013, DOI: 10.12677/HJCE.2013.23030
Abstract:
在超长混凝土结构施工中,结构配筋通常连续横穿预留温度后浇带,使其宽度变化受阻并导致设计效能减弱或消失,此时如增加后浇带宽度可对其受损效能进行补偿。针对横穿后浇带钢筋不截断情况,基于截面平衡与变形协调原理,提出了确定温度后浇带合理宽度范围的新方法,推导了技术分析过程,给出了计算例题,可供超长混凝土结构设计与施工参考。
In construction of super-long concrete structures, the width change of reserved post-casting temperature band is limited generally by the steel bars across through the band, thus its design efficacy is weakened or disappeared. In this case, the lost efficacy can be compensated by increasing width of the post-casting band moderately. For the case of steel bars are not truncated or not overlapped at the band, based on the known principle of cross-section balance and coordination deformation, the new method to determine the rational width of post-casting band is proposed, then the analysis process and the calculation sample are shown as reference for structure design and construction.
滑模施工混凝土筒仓结构的缺陷原因分析
Defect Causes Analysis for the Reinforced Concrete Silo Formed on Slipforming Construction
 [PDF]


Hans Journal of Civil Engineering (HJCE) , 2013, DOI: 10.12677/HJCE.2013.25044
Abstract:
混凝土筒仓采用滑模施工相对简便快捷,模板投资较低,可连续作业,该施工方法普遍用于混凝土烟囱、冷却塔、广播电视发射塔等高耸体形且截面规则壳体结构的浇注成型,多年来,作为专项成套技术在国内外得到了广泛应用。近年的国内工程调查表明,滑模施工混凝土筒仓的筒壳易出现以下缺陷:表层强度不同程度低于内部及设计强度,混凝土粘结握裹配筋状况较差,不规则与环向水平裂缝,对结构各项性能有明显不利影响。为此,对混凝土筒仓因滑模施工可能导致质量劣化的问题进行了分析研究,提出了相关技术建议,可供结构设计与施工人员参考。
For the slipforming construction to built reinforced concrete silos, it is not only faster and easier relatively than that in usual, but also less template investment and it brings about continuous operation. The method is still widely used to built this kind of tall and regular cross-section concrete shells, such as chimneys, cooling towers, radio and TV towers etc. and it is token as special sets of construction technology at home and abroad for many years. In recent years, a number of engineering surveys in the domestic showed that the following shell defects appeared easily in slipforming construction and affected them badly, such as surface concrete strength which was less generally than that of the internal and the design requirement, poor concrete adhesive around reinforcements, more irregular and annular cracks on silo walls. To resolve these problems, careful analysis and research are done for the quality deterioration of reinforced concrete silos due to slipforming techniques, and then some improved suggestions are proposed to the reference for relative structural designers and workers.
磨筋法与钻孔法推算混凝土构件配筋实际应力的比较研究
Comparative Study on Abrasion Method & Drilling Method to Estimate Actual Stress of Steel Bars Embedded in Reinforced Concrete Building Members
 [PDF]


Hans Journal of Civil Engineering (HJCE) , 2014, DOI: 10.12677/HJCE.2014.32004
Abstract:
既有建筑结构的安全评估、质量鉴定、加固改造,事故分析常需准确推算混凝土构件中纵筋的实际应力,依此估算构件实际内力,但目前混凝土结构检测鉴定极少能涉及或提供这些数据。磨筋法与钻孔法是作者近年首次提出的推算混凝土构件配筋实际应力的两种实用方法,均基于弹性分析结合常规检测计算求解(补充实测变量的解析计算),多项模拟试验表明其精度满足工程需要。介绍了两种方法并进行了比较与分析,证明了两者的内在联系及其一致性,结果可供混凝土结构检测鉴定与同类研究参考。分析表明,基于相同原理,经进一步改进测试工艺与精度,钻孔法还可拓展用于推算超长混凝土结构实际组合应力(含温度应力),及混凝土结构中实际预应力效应。
In security assessment, quality assurance, retrofitting and accident analysis for reinforced concrete structures, it is often needed to estimate the actual stress of longitudinal steel bars embedded in members, then as the basis, to estimate the actual internal forces of those members, but detection and identification now about existent concrete structures can hardly provide these dates. Abrasion Method and Drilling Method are the two practical ways proposed in recent years by author, which are based on elastic analysis and routine testing (analytical calculation of supplementary measured variable), and the accuracy meets engineering needs by application test verifications in past. In this paper, the two methods are introduced and comparatively analyzed, the intrinsic link and consistency between these two are proved as the reference for detection, identification and similar studies of reinforced concrete structures. Based on the same principle and further improvement of the test process and the accuracy, Drilling Method can also be used to estimate the combined stress (including temperature stress) in super-long concrete structures and the prestress efficiency in prestressed concrete structures.
高强材料置换低强灰缝提高砖砌墙体承载力的研究
Research on Low-Strength Joint Mortar Replaced by High-Strength Materials to Increase Carrying Capacities of Existing Brick Walls
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Hans Journal of Civil Engineering (HJCE) , 2015, DOI: 10.12677/HJCE.2015.42011
Abstract:
国内早年建造的大量砖混结构中,相对现行相关规范要求,墙体因灰缝砂浆抗压强度过低导致受压与抗剪承载力明显不足为主要缺陷,对其继续长期安全使用有不利影响。研究表明,用高强材料置换这些墙体各灰缝的部分低强砂浆,提高灰缝砂浆的折算平均强度,可显著增大墙砌体的受压与抗剪承载力,以此改善整体结构的抗震性能。基于《砌体结构设计规范》GB 50003-2011,对该砖墙加固方法进行了深入分析,提出了墙体截面低强灰缝置换深度的计算方法,说明了该方法的适用条件与构造要求,给出了加固设计算例。用高强材料置换低强灰缝加固墙体简便易行,能较好满足加固工程中一些特定需求,可作为现有砌体加固技术的补充供砖混结构加固设计与施工参考。
For most of early brick structures, due to strength insufficient of mortar joints in their walls, it is the major defect that compression capacity and shear capacity of the walls are clear lower than the requirement of current design code, so the long-term and safe use of them may not be determined. Research shows that the wall capacities can be added obviously and the seismic performance of brick structures including the detective walls can be improved jointly, in way of increasing average conversion strength of the mortar joints, from outer part of low strength joint mortar replaced by high strength materials. Based on Code for Design of Masonry Structures GB 50003-2011, the wall reinforcement method is analyzed deeply, the replace depth of low strength mortar joints is proposed, the suitable conditions and construction requirements are explained, the application example is given in this paper. As the complement of current similar techniques and the reference to reinforcement design and construction of masonry structures, the new method is easy to use, and also can meet some special needs of these brick structures to be reinforced.
一种新型模糊液位控制及其应用
甄新平,李全善,魏环,赵众,
化工学报 , 2008,
Abstract: 在连续生产过程中,工艺上通过设立缓冲容器来解决前后工序之间的物料量突变,以确保生产的平稳性,针对这类容器的液位控制,常规PID定值控制已满足不了上述要求。为解决这个问题,以长期现场实践为基础,根据操作人员的思维特性,提出了一种基于模糊控制和常规控制相结合的液位区域控制方法。该方法以液位的上下限和变化量作为输入模糊量化依据,改变了传统输入模糊量化方法,同时对于模糊输出量到控制输出采用新的转换方法,使模糊输出离散量转化为希望调节的液位量。为提高控制精确度,在实际控制输出与希望调节偏差较大时,增加了输出校正环节以减少输出误差。这种方法允许液位在给定的高低限范围内波动,以保证送出的物料缓慢平稳变化;只有液位超出高低限时,或液位在正常范围内,并且液位变化量超过给定阈值时才进行调节,以确保维持下游工序的负荷平稳。实际应用结果验证了这种方法的有效性。
基于RBF神经网络的流向变换催化燃烧反应器的温度预测
安娜,,陈标华,李成岳,牛学坤
化工学报 , 2004,
Abstract: 用RBF神经网络建立了用于清除低浓度挥发性有机物的流向变换催化燃烧反应器拟定态温度分布模型.从基于过程机理模型的数值计算结果出发,结合中试装置的实时操作数据建立了拟定态床层温度的人工神经元网络深层知识库,用于增强神经网络模型的“外推能力”和“可信度”.仿真结果表明所建立的模型简单、精度高,能满足特性预测的要求.
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