Deformation of Rodlike Elements of Composite Materials Subjected to Uniform Compression

On the basis of generalization of the results of investigation of the operation of rodlike elements of composite materials, we make a conclusion that the influence of various factors on the deformability of these elements is studied incompletely. The comparison of the stress-strain states for different models of concrete and reinforced-concrete elements makes it possible to describe the effect of longitudinal reinforcement (coefficient of reinforcement, strength and deformation characteristics) on the critical level of strains in the cross section. According to the results of our investigations, we give recommendations concerning the evaluation of the critical value of the coefficient of reinforcement above which one may observe the effect of reinforcement on the deformability of the analyzed sections. It is shown that the compression strength of the brittle base of the composite with inhomogeneous structure decreases as a result of the fracture processes. It is also demonstrated that the existing procedure used for the evaluation of the indicated decrease in strength requires significant improvement. The problem of evaluation of the ultimate value of the coefficient of reinforcement is also analyzed.     

大港白水头地区低阻油气层测井评价

在对白水头地区低阻油层的地质特征、物性特征及成因环境进行了分析研究后 ,应用测井曲线特征集法 ,把白水头油田常规油气层、低阻油气层、油水同层、水层等看成是独立的地质事件 ,建立了它们与测井曲线特征之间的对应关系 ,利用这种关系对未知地质事件进行了预测划分。最后根据所建模型定量计算储层各种参数 ,收到了良好的地质效果 ,表明测井曲线特征集法对于识别多成因的低阻油层是一种有效方法     

可持续发展战略指导下的轨道交通规划与评价

提出了轨道交通规划与评价在实施可持续发展战略过程中需要研究的问题，研究重点是轨道交通规划与评价方法体系和环境对策，研究了轨道交通规划目标的变化、轨道交通规划优化决策理论与方法、轨道交通规划中的环境影响评价、城市轨道交通网络的合理规划、城际轨道交通——客运专线/高速铁路线路基本走向的规划、轨道交通规划可持续发展的评价指标体系概念框架、轨道交通系统可持续发展的能力建设问题等，并通过实例验证了所建立的理论方法体系和模型体系；不仅进行了有关理论和方法的探讨，而且以面向实际应用为目标，开发了相应的软件系统，为轨道交     

Precision equipment for symmetrical bending— Part 1. The loading system

The design and performance of precision bending equipment for testing straight beams with constant rectangular section under a pure bending moment is described. Part 1 deals with the loading arrangements and Part 2 with the rig for measuring beam deflection. The methods for recording deflection of strain gauges applied on the beam have been described elsewhere.^1–4
The reactions to the deadweight gravity loads are taken via ball bearings. The total bending moment inaccuracy, i.e. the sum of estimated systematic errors and random errors, the latter expressed as the 2Ga confidence interval about the mean (2G_cim), is about ± 25 x. 10^-4%, for 23 tests with a steel beam with 15 mm × 75 mm cross sectional dimensions, loaded to 1-1.5 mm/m strain.
The measuring rig stands on the beam via hardened and polished spherical segment feet and uses a capacitive transducer system with less than 5nm resolution. Various application tasks are described. The total inaccuracy of the measured deflection, i.e. apart from bending moment inaccuracy, is about ± 35 times 10^4% for about 10 reproduced, not repeated, tests with the same steel beam. The deflection for such a beam is of the order of 2 to 4 mm.     

Visual evaluation at scale of threshold to suprathreshold color difference

Visual evaluation experiments of color discrimination threshold and suprathreshold color‐difference comparison were carried out using CRT colors based on the psychophysical methods of interleaved staircase and constant stimuli, respectively. A large set of experimental data was generated ranged from threshold to large suprathreshold color difference at the five CIE color centers. The visual data were analyzed in detail for every observer at each visual scale to show the effect of color‐difference magnitude on the observer precision. The chromaticity ellipses from this study were compared with four previous published data, of CRT colors by Cui and Luo, and of surface colors by RIT‐DuPont, Cheung and Rigg, and Guan and Luo, to report the reproducibility of this kind of experiment using CRT colors and the variations between CRT and surface data, respectively. The present threshold data were also compared against the different suprathreshold data to show the effect of color‐difference scales. The visual results were further used to test the three advance color‐difference formulae, CMC, CIE94, and CIEDE2000, together with the basic CIELAB equation. In their original forms or with optimized K_L values, the CIEDE2000 outperformed others, followed by CMC, and with the CIELAB and CIE94 the poorest for predicting the combined dataset of all color centers in the present study. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 198–208, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20106     

动态汽车衡测量结果的不确定度评定

本文主要介绍了在动态汽车衡的试验过程中不确定度来源,并以动态试验为例重点介绍了计算各分量的标准不确定度、合成标准不确定度以及扩展不确定度的方法.     

管内装元件强化传热的技术经济评价

提出了一种管内装元件强化传热的技术经济评价方法，此方法综合考虑了强化换热器管内传热膜系数的提高和管内流体阻力的增大，与普通的管壳式换热器相比，所带来的投资费用和使用费用变化，这个变化量可用净现值增量△NPV来表示。根据△NPV值来评价强化传热技术，从而为强化传热技术的开发和推广及进行决策提供指导。     

棉织物手感值的模糊综合评判研究

利用模糊综合评判数学模型对棉织物的手感值进行了计算与分析，这种方法简单、可靠，与主观评估结果有很好的一致性，为纺织生产的质量判断提供了便利。     

快速色谱分析技术在油气勘探中的应用

文章通过对五口井的现场应用介绍，阐述了快速色谱分析技术在油气层识别和解释方面的准确性，探讨了该技术在薄油气层的发现和评价、快速钻进条件下油气层的发现、对油气层全烃组份变化的统一、水平井的地质导向以及排除钻井液添加荆对油气显示的影响五个方面的优势，从而论证了快速色谱分析技术在油气勘探中的应用价值。     

基于DSP+CPLD的高精度信号发生器

介绍了基于直接数字式频率合成(DDS)原理的全数字信号发生器(DSP),利用DSP芯片快速、高精度的运算优势以及CPLD芯片灵活的编程逻辑、大容量存储功能的特点,采用通用可编程芯片以及数字波形合成技术,形成高稳定、高精度、高动态的数字合成信号.该信号发生器可产生0～25 kHz的正弦波、三角波和方波,输出电压峰峰值为0～5 V,频率步进1 Hz,幅度步进0.001 V.