水库淤积测量点云剖面分析系统研发与应用

针对水库淤积测量范围广、点云数据密度大,淤积分析中剖面提取耗时长,研发水库淤积测量点云剖面分析系统。首先在三维可视化中读取水库不同时期的水下三维点云数据;然后通过交互式操作拾取点云对应的区域两点坐标,生成竖直向的剖面;再计算所有点云数据到剖面的距离,筛选出该距离满足小于某个阈值条件下的所有点,投影到剖面上,拟合出不同时期剖面线进行对比分析。工程实例表明,该系统为水库不同时期淤积程度分析提供一种简单、快速的技术手段,具有较好的应用推广价值。     

输气钢管内壁椭圆形坑失效原因分析

为分析某输气用X52QS钢级无缝钢管内壁椭圆形凹坑失效原因,通过力学性能测试、金相检测、化学成分分析、扫描电镜（SEM）、物相（XRD）分析等手段,对该凹坑产生原因进行综合分析。结果发现,凹坑区的C、Cr、Mo、Ti、B等元素含量高于正常区,且偏聚在凹坑区;C、B元素含量超标,化学成分不均导致凹坑区金相组织不均匀,使凹坑区发生微观原电池反应,凹坑区成为阳极被腐蚀而减薄;此外,凹坑内表面的CaCO3和SiO2含量较高,造成凹坑区垢下腐蚀;凹坑区表面膜疏松造成浓差电池,在介质冲刷等共同作用下会加速腐蚀,凹坑区壁厚持续减薄,最终形成更大的椭圆形凹坑。最后对样管最薄凹坑剩余厚度进行计算,发现已无法满足设计压力要求,建议换钢管或者降低设计压力后二次利用。     

静电火灾产生机理与防护路径

由于静电在工业生产的过程中会不断集聚,最后造成放电.文章将从静电火灾爆炸出发,分析工业生产过程中的静电火灾危险,并为预防这一火灾危险提供建设性的意见.     

Lightweight design of automotive front side rails with TWB concept

Due to the continuous tightening of various regulations for conserving energy and protecting the environment, the weight reduction of and automobile body becomes an increasingly important issue. In order to reduce the weight of an automobile, we have brought forward a method of replacing the simple structure with the tailor-welded blank (TWB), in which a design process is appropriately defined for a front side rail. Focusing on the thickness determination of TWB, we have deduced the constraint inequalities of strength, bending stiffness, and torsion stiffness to prevent the thickness from decreasing unboundedly due to the lightweight requirement, thus reducing the weight of the front side rail satisfying the design demands of these three factors. The full-width frontal impact simulation of the whole car after redesign in the front side rails has been performed to verify vital performances such as deformation mode, energy absorption, and acceleration.     

Adaptive Dynamic Surface Control of Nonlinear Switched Systems with Prescribed Performance

This paper studies the adaptive control problem for a class of switched nonlinear systems with guaranteed prescribed performance bounds under arbitrary switchings. The unknown system functions are approximated by radial basis function neural networks. We employ dynamic surface control technique to solve the explosion of the complexity problem. We control the transformed system such that it is stabilizable, by this way, the original system is stabilizable as well as the prescribed performance is guaranteed. The proposed controller and update laws guarantee the stability of the closed-loop system and the boundedness of all signals. Furthermore, the prescribed performance is ensured. Finally, a simulation example is employed to illustrate the effectiveness of the proposed method.     

垃圾在流化床中燃烧特性的实验研究

在一台特别设计的小型流化床燃烧实验台上对垃圾可燃物代表组分进行实验研究。实验结果表明,干燥的垃圾一般在床温仅为500℃就能在很短的时间内迅速燃烧,产生明亮的火焰,并使炉膛温度急剧上升．对于个别物料,例如橡胶在短时间内可能出现炉膛中部温度高于床温的情况、物料的形状变化对于它们在流化床内的燃烧影响较大。一般来说,当物料剪碎后,燃烧产生CO量将有所降低,同时炉膛中部温度升高很多。     

高陡岩质边坡块体稳定性研究方法及应用

针对高陡边坡稳定性问题,以乌东德水电站为例,借助Adam三维数码照相技术在地质编录的独特优势,结合三维块体稳定性分析技术,建立了一套高陡岩质边坡块体稳定性研究的系统方法,并与传统方法进行了比较.结果表明,该方法可确定块体发育位置、特征、规模及稳定性,且高效、准确、安全,为工程设计与施工提供了重要依据.     

金属栅条掩埋型纳米光栅的设计与制备

An embedded wire-grid nanograting was designed and fabricated for using as a broadband polarizing beam splitter to reflect s-polarized light and transmit p-polarized light. A protected cladding layer of the same material as the grating＇s was deposited on the ridge, whereas the wire-grid is deposited in the grating trenches, which makes it more firm during application. High polarization extinction ratios of above 40 and 20 dB for transmission and reflection, respectively, with a broad wavelength range for the whole optical communication bandwidth （850 -1700 nm） and a wide angular tolerance （〉 ±20 °） are obtained by optimization of the designed structures, and the grating period is 200 nm.     

关于节能降耗与电力市场联合实施方案的探讨

为促进电力工业节能降耗有效开展和电力市场的实质推进,文中从技术上探讨了节能降耗和电力市场联合实施的方案.首先探讨了电力行业进行节能降耗的措施;然后重点探讨了发电侧节能降耗的调度方法和市场化方法.节能调度方法主要根据发电煤耗、厂用电、网损、排污水平等多种因素确定发电的优先级,市场方法主要根据市场主体报价和造成的网损变化确定机组发电优先级.探讨了节能调度与市场化联合实施的可能性,并提出了一套技术方案;最后定性、定量分析了煤耗、网损、排污水平、报价等因素对机组排序的影响.     

锚杆拉剪大变形应变分析

采用基于Ｓ－Ｒ定理的大变形理论,运用拖带坐标描述法,研究了锚杆在节理岩石中的拉剪局部大变形行为,推求了锚杆大变形应变的计算公式,得出了锚杆拉剪应变分量的理论规律,指出可以通过位移量测确定锚杆变形与内力,由多种岩石加锚剪切实验结果证实了理论方法的正确可靠。