小波分析及其在时变滤波和信号分离中的应用

利用小波变换具有的多时频分辨率特性，对地震勘探和测井信号这类非平衡信号进行分析，可以充分利用信号的时间－频率特性。文中介绍了小波变换的基本概念及其在地震勘探信号的时变滤波和声波全波列测井信号的信号分离中的应用，实例表明，小波变换在地球物理信号中具有广阔的应用前景。图５参７     

Study on combustion characteristics of blended coals

Power plants in China have to burn blended coal instead of one specific coal for a variety of reasons. So it is of great necessity to investigate the combustion of blended coals. Using a test rig with a capacity of 640 MJ/h with an absolute milling system and flue gas online analysis system, characteristics such as burnout, slag, and pollution of some blended coals were investigated. The ratio of coke and slag as a method of distinguishing coal slagging characteristic was introduced. The results show that the blending of coal has some effect on NO _x but there is no obvious rule. SO _x emission can be reduced by blending low sulfur coal. Translated from Proceedings of the CSEE, 2005, 25(18): 97–103 [译自: 中国电机工程学报]     

世界汽车及其润滑油的发展与排放的相关性分析

介绍了美国，欧洲，日本，中国汽油机油与柴油机油的发展过程，现状，趋势及其与排放的相关性，指出：90年代美国环保要求与节能变得更加严格，美国内燃机油规格进展充分反映了这一变化；欧洲，日本进入21世纪总的方向也是如此；中国的轿车工业主要是世界知名汽车厂商合资生产，其内燃机油规格遵守世界汽车厂商的要求，基本上跟随欧洲规格。     

A fictitious domain decomposition method for the solution of partially axisymmetric acoustic scattering problems. Part I: Dirichlet boundary conditions

We present a fictitious domain decomposition method for the fast solution of high‐frequency acoustic scattering problems characterized by a partially axisymmetric sound‐soft scatterer. We apply this method to the solution of various mockup submarine problems, and highlight its computational advantages and intrinsic parallelism. Copyright © 2002 John Wiley & Sons, Ltd.     

伪波阻抗反演在准噶尔盆地永进油田储层描述中的应用

永进油田目的层产状平缓,断层不发育,储层厚度小、埋深大、描述困难。运用伪波阻抗技术对该区的储层进行了研究,取得了较好的效果。     

燃气红外线辐射器的节能与环保特性分析

论述了燃气红外线辐射器的基本原理 ,对其节能与环保特性的分析表明 :与大气式燃烧器相比 ,红外线辐射器的燃料节约率为 15 %～ 45 % ,CO2 排放量减少率为 15 %～ 48% ,CO排放量减少率为 96.2 %～ 97.7% ,NOx 减少率为 94.9%～ 96.9% ,具有显著的节能与环保效果     

Tensile fracture and failure behavior of technical flax fibers

The apparent tensile strength of technical flax fibers was determined in single‐fiber tests at various clamping lengths (20, 40, and 80 mm) and the outcome was compared with literature data. It was demonstrated that the strength of flax at each clamping length obeyed the two‐parameter Weibull model. The failure mode and sequence were studied in situ (i.e., during loading) by SEM and acoustic emission (AE). The failure sequence (axial splitting of the technical fiber along its elementary constituents, radial cracking of the elementary fibers, multiple fracture of the elementary fibers) concluded reflected the hierarchical build‐up of the flax bast fibers. To the above failure events AE amplitude ranges were assigned. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3638–3645, 2003     

多层频率选择表面的分析

本文利用矩量法和广义散射矩阵理论分析了多层频率选择表面的散射特性。通过引入广义波导概念,可以统一分析单元形状为任意的多层频率选择表面。作为示例,计算了几种不同结构频率选择表面的散射特性,结果与文献中给出的数据相符。     

一种新型声波降粘防蜡装置

新型声波降粘防措装置由上、下接头、振动簧片和收缩喷嘴构成。装置安装在抽油泵泵简之下，尾管之上，在压差作用下井下流体以较大速度从装置的喷嘴射出，冲击振动簧片，产生机械振动声波，油水混合液在声波中产生相应的声波力学效应和分散乳化作用等，使混合液在油管内的粘度降低，蜡晶不易聚集长大，从而达到降粘防蜡延长油井热洗周期的目的。室内试验及现场近20口井的应用情况表明，这种装置具有结构简单、成本低廉、应用方便等特点，具有明显的降粘防蜡效果。     

FED制作工艺研究

本文介绍了我们开发的ＦＥＤ工艺，包括；硅锥场致发射阵列的制作，栅极制作，阳极支柱的制作和平板透明真空封装，对工艺中的难点及对策作了详细描述。利用上述工艺，已经制成了平板数码管，其栅阴特性理想，阳阴之间也能测得明显的场致发射特性产伴有荧光激发。