High accuracy path tracking for vehicles in presence of sliding: Application to farm vehicle automatic guidance for agricultural tasks

When designing an accurate automated guidance system for vehicles, a major problem is sliding and pseudo-sliding effects. This is especially the case in agricultural applications, where five-centimetre accuracy with respect to the desired trajectory is required, although the vehicles are moving on slippery ground. It has been established that RTK GPS was a very suitable sensor to achieve automated guidance with such high precision: several control laws have been designed for vehicles equipped with this sensor, and provide the expected guidance accuracy as long as the vehicles do not slide. In previous work, further control developments have been proposed to take sliding into account: guidance accuracy in slippery environments has been shown to be preserved, except transiently at the beginning/end of curves. In this paper, the design of this control law is first recalled and discussed. A Model Predictive Control method is then applied in order to preserve accuracy of guidance even during these curvature transitions. Finally, the overall control scheme is implemented, and improvements with respect to previous guidance laws are demonstrated through full-scale experiments.     

新型埽工--笼埽在黄河控导工程中的应用

介绍了新型埽工——笼埽的结构形式、施工方法，其优点为：(1)克服传统埽工施工工序复杂、速度慢、效率低的缺点；(2)笼埽可工厂化生产，减少现场作业工序和作业面后移；(3)充分利用大型施工机械进行大体积单个笼埽结合机械化施工，作埽速度快、强度高；(4)减少柳料用量，利于环境保护．结合在兰考蔡集控导工程水中进占工程中的应用，从施工准备、机械配合与人员安排及施工流程等方面对笼埽施工技术作进一步说明，并总结了施工注意事项．最后，进行了效益评价并提出了扩大技术应用范围和进行水槽实验的完善思路．     

间接原子吸收分光光度法测定聚丙烯、聚乙烯中的微量(?)

介绍用原子吸收分光光度法测定PE、PP氯含量。该方法采用氧气燃烧法处理样品,用Ag~+沉淀Cl~-,经分离后用原子吸收光谱测溶液中剩余Ag~+浓度,从而得到样品中氯含量。讨论了仪器参数、操作条件对测定结果的影响,结果表明,在分离前存放4～30分钟对测试结果无影响。火焰法的测定条件为波长328.1nm、灯电流7.5mA、狭缝宽度0.4nm、C_2H_2压力0.025MPa、空气压0.16MPa、燃烧器高度7.5mm。实验采用的离心转速2000r/min、时间5分钟、HNO_3浓度1%。该法灵敏度可达0.1μg/ml、相对标准误差<2%。     

重油催化裂化装置高温烟气冷却器的改造

对重油催化裂化装置原有的高温烟气冷却器进行改造的情况和改造后的烟冷器的优点进行了详细论述，并对烟冷器改造后带来的经济效益作了简要介绍。     

漫谈汽车产品的包装

从汽车外形设计、车身色彩及内装饰三个方面讨论汽车内外包装的发展现状和有关走向，并指出这方面正有迅猛的发展势头，以上起包装界和汽车设计界的高度重视。     

底部框剪砌体房屋空间弹塑性地震反应分析

本文提出了底部框剪砌体房屋这类上下混合承重结构体系的空间弹塑性地震反应时程分析方法。针对砌体结构和框架抗震墙结构截然不同的抗震性能，对上部砌体结构采用空间剪扭分析法，而对下部框架抗震墙结构采用空间协同分析法，建立了组合型串联刚片系振动模型。对单向和双向地震波输入结构层位移反应进行了比较。     

轴测投影非轴向伸缩系数及与轴测轴的夹角

导出了正轴测图中投影面平行线的伸缩系数及其与轴测投影轴的夹角计算公式,使得各种形状形体的轴测投影画法更简单、尺寸量取更精确.     

泥炭土地基钻孔漏浆的处理

以云南鸡石一级公路青鱼湾大桥为例，介绍了在软弱地层中施工桥梁钻孔灌注桩遇孔壁开裂漏浆时的处理方法，经试验证明，取得了较好的技术经济效果。     

Granular Reasoning Using Zooming In & Out: Part 2. Aristotle's Categorical Syllogism

The concept of granular computing is applied to Aristotle's categorical syllogism. Such kind of reasoning is called granular reasoning in this paper. For the purpose, two operations called zooming in & out are introduced to reconstruct granules of possible worlds.