集装箱起重机液压减摇系统的主要影响因素

为分析影响减摇效果的主要因素和关键参数,根据液压减摇系统的结构、小车吊重系统的运动特点和工程需要,建立了简化的系统动力学模型.仿真研究表明,起升绳长不变时,液压减摇系统结构参数和起升载荷是影响减摇效果的关键参数和主要因素;当起升质量（或结构参数）一定时,减摇系统的减摇效果取决于结构参数（或起升质量）;系统的最佳结构参数与载荷的比值的范围为1.6-2.0 s^-1.     

Stability Study of Cable-Suspended Stewart Platform

The control stability of the end manipulator of a cable-suspended Stewart platform in disturbance was studied by combination of the multi-body system dynamics and control theory and the eigensystem realization algorithm (ERA). The corresponding closed-loop vibration control strategies were suggested based on position prediction with PD (proportional plus derivative) control.Numerical simulation was made on a scale model to study the vibration control effects of the stewart platform with flexible suspension, including system response to step load, system response to cyclic load, and instability. Then, experiments for Stewart platform with cable suspension were designed to study the actual control effects and validate the validity of numerical simulation. The results show that the experimental results agree with the simulation results well, and the the system has a fairly good control effect to the end manipulator. Therefore, a preliminary conclusion can be made that it is feasible using the Stewart platform as the vibration control platform of the flexible support system, by position prediction of the base platform and PD feedback control law.     

不同出行距离的客货运量分布研究

根据客货出行的随机性以及组成理论中的最复杂原理,可推导出客货出行距离的概率分布,得出客货出行的规律,从而为交通规划以及运输规划提供依据,同时也为客货出行特性的研究提供新的思路。     

数据挖掘与数字图书馆个性化服务

文章介绍了数字图书馆个性化服务及其相关服务方式,阐述了数据挖掘相关原理,给出了数字图书馆利用数据挖掘技术构建个性化服务模型的过程.     

列流线偏移描绘自动化

基于图论理论分析了列流图的组成特性,以解决列流线折点自动搜索问题.提出列流线折点搜索算法和列流线偏移描绘算法.采用基于节点信息表绘制列流图.开发了列流图自动生成数据库系统.用实例表明了算法及软件有效性和可行性.     

谷氨酰胺对严重烧伤后肠黏膜和机体免疫功能保护作用的临床观察

目的 探讨谷氨酰胺对严重烧伤患者肠黏膜屏障作用的影响.方法 将入选的严重烧伤病例分为对照组和治疗组,治疗组伤后应用谷氨酰胺颗粒10 g口服,3次/d,对照组接受安慰剂.于烧伤后第1、3、7、14天检测各组患者外周血二胺氧化酶(DAO)、D-乳酸、血清IgG、IgM、CD4+/CD8+及转铁蛋白.结果 与对照组相比,治疗组烧伤后外周血DAO和D-乳酸水平无明显增高,在第7、14天均显著低于对照组;烧伤后第14天血清IgG、IgM、CD4+和CD4+/CD8+均显著高于对照组;烧伤后第7、14天转铁蛋白水平亦高于对照组.结论 应用谷氨酰胺能够对严重烧伤后肠黏膜屏障起到保护作用,同时也能在一定程度上促进患者免疫功能和营养状态的改善.     

Effects of systemic domestic recombinant human erythropoietin on HIF-1α expression in the retina in a rabbit model of acute high intraocular pressure

Objective To observe the expression of hypoxia inducible faetor-1α (HIF-1α) in the retina of rabbits with acute high intraocular pressure and to investigate the mechanism of systemic domestic recombinant human erythropoietin (rhEPO) protecting the retina from ischemia-reperfusion injury. Methods First, control group and model group were established in rabbit eyes. The acute high intraocular pressure model was established by saline perfusion into anterior chamber, and then hypodermic injection of domestic rhEPO was made. HIF-1α protein in the retina was observed by immunohistochemical staining method on days 1, 3, 7 and 14 after retinal ischemla-reperfusion, respectively. Results No cells with HIF-la positive expression were observed in the retina of the control group. Ceils with HIF-1α positive expression in the model group outnumbered those in the control group (P < 0. 01). The resemblance pattern occurred in EPO group but its degree was slightly greater than that in the model group from day 3 after ischemia-reperfusion (P<0.05). Conclusion Domestic rhEPO can down-regulate the expression of HIF-1α in the retina with acute high intraocular pressure, which may be one of the mechanisms that rhEPO protects the retina from ischemia-reperfusion injury.     

区域间相互作用大小的时空可视化方法

为解决现有区域间相互作用大小可视化结果缺乏可比性和受时间点限制的问题,提出了一种不受时间点限制的区域间相互作用的时空可视化方法.该方法以空间相互作用模型为基础,将区域中心点作为可视化结果的中心点,分别按区域受到的相互作用总量和与相邻区域间的相互作用计算可视化结果的半径和角度,实现了区域间相互作用的时空可视化.以四川省的7个地区为例,证实了该方法具有较强的可比性和易读性.     

高速公路桥梁伸缩装置的维修与更换

就桥梁伸缩装置破坏的原因进行分析,阐述了模数式桥梁伸缩装置维修更换的施工工艺及注意事项。     

边坡冲刷量的神经网络计算模型

在分析坡面冲刷过程与神经网络模型特点具有某些相似的基础上,选取降雨强度、径流量、坡度、土的粘性为输入量,以MATLAB为工具,通过试算法确定最佳的隐层节点数,建立网络模型。并通过验证试验,显示此模型具有较好的模拟预测效果。