基于磁场强度的锅炉管内氧化皮测量精度实验

因高温高压蒸汽作用,超临界电站锅炉受热管内易形成氧化皮,氧化皮的剥落会堵塞管道,发生超温爆管。提前探测氧化皮的状况并采取相应措施对预防爆管十分必要.文中在比较几种氧化皮探测方法的基础上,应用磁场检测法,通过实验研究了探头与管道的间隙、探头与管径的偏角、永磁体相对氧化皮的位置等因素对磁场探测结果的影响,发现间隙小于1.07mm、角度偏离中法线25.9°内、相对位置在26.4°内时,测量误差可控制在5%的工程误差以下,且探头与管道的间隙是影响磁场测量结果的主要因素;随着偏角与相对位置的增大,测得的磁场强度呈指数增长.     

云计算环境下大数据视频图像的尺度空间融合算法研究

针对传统算法融合图像质量差、清晰度低、损失图像包含信息的弊端,提出一种新的云计算环境下大数据视频图像的尺度空间融合算法,介绍了尺度空间理论。通过具有平移不变性特征的提升静态小波变换算法对云计算环境下大数据视频图像进行尺度空间融合,对待融合图像进行提升小波变换分解处理,获取不同尺度空间下的低频子带系数与高频子带系数。针对低频子带系数与高频子带系数给出各自的融合方案,获取融合图像的提升静态小波变换系数。通过提升静态小波逆变换获取最终的融合图像。从主观和客观两个方面对所提算法的融合效果进行测试。结果表明,所提算法主观融合效果好,通过客观评价指标对融合图像进行评价,发现所提算法得到的融合图像清晰度、质量佳,不会损失图像包含信息。     

基于DEA模型的中国石油企业科技效率研究

运用DEA投入导向模型,根据2000—2011年公开数据,选取科研与开发投入占总销售收入的比例、总资产、总资产周转率和资产负债率作为投入指标,选取油气探明储量、净资产收益率、净利润和总收入作为产出指标,以中石油、中石化以及中海油三大巨头为例,对我国石油企业的科技效率水平进行综合评价,并提出了提高我国石油企业科技效率的建议.     

利用二次分解——集结法研究离散大系统的稳定性

本文分别用标量李雅普诺夫函数和向量李雅普诺夫函数利用二次分解——集结法,给出了由差分方程所描述的离散大系统的全局一致渐近稳定的三个充分条件,还用标量李雅普诺夫函数给出了大系统全局指数稳定的一个充分条件。     

基于优化氧化铁皮和焦粉配比的铁矿烧结过程NOx减排研究

Reducing NO_x emission of iron ore sintering process in a cost effective manner is a challenge for the iron and steel industry at present. Effects of the proportion of mill scale and coke breeze on the NO_x emission, strength of sinter, and sinter indexes were studied by combustion and sinter pot tests. Results showed that the peak value of NO concentration, total of NO emission, and fuel-N conversion rate gradually decreased as the proportions of the mill scale increased because NO was reduced to N₂ by Fe₃O₄, FeO, and Fe in the mill scale. The strength of sinter reached the highest value at 8.0wt% mill scale due to the formation of minerals with low melting point. The fuel-N conversion rate slightly fluctuated and total NO_x emission significantly decreased with the decreased proportions of coke breeze because CO formation and content of N element in the sintered mixture decreased. However, the sinter strength also decreased due to the decrease in the amount of the melting minerals. Furthermore, results of the sinter pot tests indicated that NO_x emission decreased. The sinter indexes performed well when the proportions of mill scale and coke breeze were 8.0wt% and 3.70wt% respectively in the sintered mixture.     

粗粒土大型单剪颗粒破碎试验研究

使用新研制的大型单剪仪,对粗粒土的颗粒破碎及粗粒土一结构接触面进行了系统的试验研究,分析了试验中影响颗粒破碎的主要因素及颗粒破碎对粗粒土一结构接触面应力应变特性的影响.试验结果表明,颗粒破碎率随着法向应力的增大而增大,颗粒破碎受剪应力大小的影响程度随着法向应力的增大而减小.     

粗粒料缩尺效应研究现状与趋势

总结了粗粒料室内试验不同缩尺方法的优缺点、目前粗粒料强度和变形试验常用仪器的优缺点以及这些仪器用于研究粗粒料强度和变形的代表性成果;概括了缩尺效应对粗粒料强度和变形特性影响方面的研究成果;分析了缩尺效应的评价依据;讨论了缩尺效应研究中应考虑和注意的一些问题,如试样密度的控制、缩尺效应的定量化表述等,并指出缩尺效应研究应注意替代级配料和原级配料的密度控制方法.     

中国风电产业的规模和效率探析——以内蒙古自治区为例

对中国数百家风力发电场2008~2010年的发电装机容量和发电效率进行了分析,发现中国的风电场的规模和效率都在递增,但风电场的规模和效率之间的相关性逐年递减,甚至出现了负的相关性。进一步分析了风电第一大省内蒙古的情况,显示装机容量的规模存在着反常的现象,而且装机容量和发电效率之间的相关系数也不稳定。据此分析,对现行的风电发展政策提出了疑问,并给出了相应的政策建议。     

New species of Hygiella Mesnil (Diptera: Tachinidae), parasitoids of leaf insects (Phasmatodea: Phylliidae)

The Oriental genus Hygiella Mesnil is revised: three species are described as new, Hygiella angustifrons sp. nov., Hygiella luteipes sp. nov. and Hygiella proclinata sp. nov., and two known species are re-described, Hygiella nigripes Mesnil and Hygiella pygidialis Mesnil. A key to these five species is provided. The host of H. proclinata, Phyllium siccifolium (Linnaeus) (Phasmatodea: Phylliidae), is recorded for the first time as a host of the Tachinidae. The systematic position of Hygiella is discussed and the genus is placed in the tribe Acemyini (Exoristinae) based on the structure of the male terminalia.     

Observations on the spectral reflectances of certain high Andean Penaincisalia and Thecloxurina,with the description of a new species (Lepidoptera: Lycaenidae: Eumaeini)

The eumaeine hairstreak species Thecloxurina tegulina Bálint and Boyer, sp. n. from SW Peru, department Apurímac (type locality: Karkatera, NW of Ampay, 3,200 m, 13°34′286″S; 72°58′501″W) is described on the basis of qualitative and quantitative wing pattern, male genital and spectral characters. The spectral reflectance of the closely related genera Penaincisalia and Thecloxurina are investigated and compared. It is demonstrated that the spectral characteristics of the two genera are qualitatively differing, and the taxa investigated representing the two genera (Penaincisalia:Thecloxurina = 3:5) also have characteristic species dependent reflectance peaks measured at normal incidence.