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41.
地震数据通用压缩文件格式设计 总被引:1,自引:0,他引:1
本文从生产实际需要提出了进行地震数据压缩和制定规范的压缩数据文件格式的要求,按照通用性,兼容性,可扩充性,操作简便,高缩效率几方面的要求设计了通用压缩数据文件格式及一种具体形式,讨论了数据压缩的具体策略和方法,试验表明,采用压缩数据文件格式,不但可以大比例地减小数据存贮空间(压缩比达4:1-10:1),而且可以大大加快数据的I/O速度(提高1倍以上)。 相似文献
42.
柳襄怀 《有色金属材料与工程》1994,15(2):65-72
作者在多年实验工作的基础上,论述了离子束增强沉积薄膜合成及其在材料表面优化中的应用、所用设备、膜的合成、表面优化技术与机理,并展望了前景。 相似文献
43.
44.
因场地淤泥等软土层深厚,在填方荷载作用下,软弱土层产生固结沉降,引起局部构筑物的不均匀沉降,发生结构破坏。采用微型灌注桩加固满足现场各个限制条件的要求,达到了加固目的。 相似文献
45.
Thermochemical analyses of interfacial reactions in titanium, zirconium, and hafnium diboride reinforced oxidematrix composites have been carried out to evaluate the chemical compatibility. The chemical reactivity of these diborides with oxygen and the high volatility of B2 O3 ( l ) at reduced oxygen pressures are concerns during processing and operating conditions. The thermochemical stability and the vaporization behavior of B2 O3 ( l ) are discussed in terms of partial pressures of dominant gaseous species of the boron-oxygen system at 1700 and 2300 K. The TiB2 /ZrO2 and TiB2 /HfO2 systems are thermodynamically stable in a limited oxygen pressure range. The TiB2 /Al2 O3 system is stable, but the reactions in this system may apparently be accompanied by formation of gaseous products (B2 O3 , AlO, Al2 O, and lower boron oxides) in the presence of elemental oxygen. These thermochemical considerations are very useful in evaluating the effectiveness of oxides as diffusion barrier coatings on diboride reinforcements. 相似文献
46.
V Živica 《Bulletin of Materials Science》1995,18(2):115-124
The paper describes a method for the mathematical modelling of steel reinforcement corrosion rate. This method is based exclusively
on experimental results and expression of the influence of significant corrosion factors in the form of functional relations.
The method takes into account the reality of the effects of corrosion factors, their contigency and complexity, and various
circumstances occurring in practice. It represents one way towards the development of methods for the prediction of service
life of reinforced concrete and structures. 相似文献
47.
用有限元确定起重机裂纹补强板的参数 总被引:1,自引:0,他引:1
采用ANSYS有限元分析软件,对因出现裂纹的起重机主梁而添加的补强板进行系列计算,得出修补后主梁裂纹的应力及应力强度因子的变化规律。结果表明,采用参数适当的补强板,可降低起重机主梁裂纹尖端的应力,从而保证起重机的安全。 相似文献
48.
Evaluating Liquefaction Strength of Partially Saturated Sand 总被引:1,自引:0,他引:1
A method is presented for evaluating the liquefaction strength of partially saturated sand using the compression wave velocity (P-wave velocity), a new indicator of saturation. Based on laboratory test results, an empirical correlation that relates the liquefaction strength with the pore pressure coefficient B is firstly proposed. The strength is defined as the cyclic stress ratio required to cause liquefaction at a specified number of cycles. With the aid of a theoretical relation between B and the P-wave velocity, an explicit correlation of more interest is then established between the liquefaction strength of sand and its P-wave velocity. A comparison of the predictions using this explicit correlation with laboratory measurements shows a satisfactory agreement. The significance of this method lies in that it makes it possible to evaluate the liquefaction strength of sand as affected by saturation through the measurement of P-wave velocity, which can be made not only in the laboratory but particularly in the field. 相似文献
49.
50.
Hemanshu Bhatt Kimberly Y. Donaldson D. P. H. Hasselman Kenneth Chyung Mark P. Taylor 《Journal of the American Ceramic Society》1991,74(6):1463-1465
A study concerning the effect of fiber orientation on the thermal conductivity of a uniaxial carbon-fiber-reinforced borosilicate glass was conducted. For thin specimens, and thick specimens with specimen sides cut parallel to the fiber direction, the dependence of thermal conductivity on fiber orientation showed excellent agreement with theoretical behavior predicted for a composite infinite in extent. In contrast, the thermal conductivity data for rectangular thick specimens fell well below the data for the thin and angled specimens. For fiber orientation of 45° and higher, at which the heat was directed toward the side of the specimen rather than across, the thermal conductivity values showed excellent agreement with theoretical behavior predicted for a finite composite strip with insulated sides. 相似文献