DLG产品质量的模糊综合评判

根据DLG产品的质量特性及相应的权值，采用模糊数学的方法进行评价。通过选用不同的隶属函数和不同的评判模型对同一数字线划图进行了评价，得出了一些有益的结论。     

人工神经网络在桩基工程中的应用综述

对人工神经网络在桩基工程中的应用研究工作进行了回顾与评述。总结了神经网络在单桩承载力、荷载－位移关系预测以及基桩动测完整性判释等方面的技术成果与水平，并分析和探讨了进一步的研究方向和应用前景。     

形变反演模型的非线性平差

阐述了反演问题参数估计的质量要求，将反演理论中的分辨率和精度与平差中的良好统计性质作了对比分析，为使反演参数得到良好估计，提出平差处理对策。针对反演问题经常是非线性模型，提出了非线性平差的几种方法，最后给出参数筛选的原则和相应的统计检验方法。     

An experimental investigation of water level effects on the dynamic behaviour of a large arch dam

The need for full‐scale dynamic tests, which are recognized as the most reliable method to evaluate a structure's vibration properties, is increasing as new analysis techniques are developed that take into account the complex interaction phenomenons that occur in dam–reservoir–foundation systems. They are extremely useful to obtain reliable data for the calibration of newly developed numerical methods. The Earthquake Engineering and Structural Dynamics Research Center (CRGP) at the University of Sherbrooke has been developing and applying dynamic testing methods for large structures in the past 10 years. This paper presents the experimental evaluation of the effects of the varying water level on the dynamic response of the 180 m Emosson arch dam in Switzerland. Repeated forced‐vibration tests were carried out on the dam during four different periods of the reservoir's filling cycle during a one‐year span. Acceleration and hydrodynamic pressure frequency responses were obtained at several locations while the dam was subjected to horizontal harmonic loading. The variation of the resonant frequencies as a function of the reservoir level is investigated. A summary of the ongoing numerical correlation phase with a three‐dimensional finite element model for the dam–reservoir–foundation system is also presented. Copyright © 2001 John Wiley & Sons, Ltd.     

Correlation of hydraulic conductivity with stratigraphy in a fractured-dolomite aquifer, northeastern Wisconsin, USA

This study integrated surface and subsurface stratigraphic data with geophysical logs and hydrogeologic data in order to characterize the hydraulic properties of the Silurian dolomite in northeastern Wisconsin. Silurian stratigraphy consists of predictable alternations of characteristic facies associations. A vertical profile of hydraulic conductivity, obtained from short-interval packer tests in a core hole that penetrates a majority of the Silurian section, indicates that hydraulic conductivity ranges over five orders of magnitude (10^–1 to 10^–6 cm/s). Matrix conductivity is generally low and varies with texture; the finer-grained restricted-marine and transitional facies being less permeable than the coarser-grained open-marine facies. High-conductivity values are generally associated with bedding-plane fractures, and fracture frequency is greater in the restricted-marine facies. High-flow features in 16 wells were identified using fluid-temperature/resistivity and heat-pulse flowmeter logs. Natural-gamma logs were used to identify the stratigraphic position of flow features in each well and to correlate flow features to specific stratigraphic horizons. By combining stratigraphic, geophysical, and hydrogeologic data, 14 high-permeability zones within the Silurian aquifer have been identified and correlated in wells more than 16 km apart. These zones parallel bedding, appear most pronounced at contacts between contrasting lithologies, and are most abundant in restricted-marine lithologies. Electronic Publication     

水文水井抽水试验参数自动监测系统的研制与应用

将现代计算机检测技术与水文水井抽水试验相结合，开发研制了多参数自动监测系统，可对抽水试验中孔内水位、水温和出水量进行实时同步检测，该系统在实际工程中得到了应用与验证。介绍了该系统的组成、检测原理、主要性能参数及生产试验情况。     

Seeing Conditions at Sutherland. Results of the 1992/93 seeing campaign

In order to decide whether the seeing conditions at SAAO/Sutherland justify the erection of a 3.5 m telescope and also to compare Sutherland with the Gamsberg/Namibia site, a seeing campaign covering 15 months has been carried out. For direct comparison with the results of the seeing campaign at Gamsberg twenty years before the same QUESTAR telescope was employed. The seeing is determined by the scattering of the star-trail exposed on a film in the focal plane of the telescope. The campaign commenced in February 1992. Up to May 1993, data for 204 nights, that is 47.3% of the total number of nights, were collected. Due to wind speeds above 30 km h^-1, 25 out of the 204 nights were not considered in the final reduction. The useful 179 nights are evenly distributed over the campaign period. The median seeing value for the whole period is = 0.52. There are differences during the year: the best season gives = 0.42, the worst = 0.67. Each night was divided into three intervals, although data for each of the three intervals were not always available. Generally, there is an improvement in the seeing during the course of a night. The results are compared to the seeing values of Gamsberg/Namibia and ESO/La Silla.     

工业CT技术在卫星产品检测中的应用

卫星产品许多都采用了焊接结构。为了保证其使用的安全可靠性,必须对焊缝进行l00％的无损检测。然而对于一些形状复杂的精密电子束焊件,由于产品尺寸小,加之焊缝周围结构的遮挡,使常规方法的应用受到了限制。工业CT技术具有不受试件材料种类、形状结构及表面状况限制的特点,能给出与试件材料密度及尺寸特性相对应的断层扫描图象,分辨率高,在检测复杂构件方面显示出了优势。本文介绍了卫星产品精密复杂焊接件对无损检测技术的具体要求,研究了卫星产品电子束焊缝的工业CT检测方法,包括设备、对比试样、检测工艺、评定方法等,并通过电磁阀、喷注器、自锁阀、减压器、加注/排放阀、单向阀、气滤、过滤器等具体产品检测实例,描述了工业CT技术在卫星产品检测中的应用。实际应用表明：工业CT是检测航天卫星产品精密复杂结构件焊缝缺陷的理想手段,其成象直观,缺陷的定位、定性和定量结果可靠,完全能满足产品的质量控制要求。目前,累计用工业CT检测卫星产品数批若干件,检测焊缝上千条。剔出有超标缺陷的产品40件,避免了隐患。经过工业CT检测的产品,己在"返回式卫星"、"风云二号"、"东方红三号"、"资源一号"、"中星-22号"等型号卫星中取得了成功应用。     

相位激发极化法应用研究

相位激发极化法是一种频率域激发极化方法,可直接测量电场电压与供电电流之间的绝对相位差。由于该方法对仪器精度要求较高,因而国内有关实际应用方面的资料相对较少。在金属矿产勘查中,目前国内大多采用时间域激发极化方法,测量岩矿石的极化率或充电率。虽然频率域激发极化法也有应用,但主要采用双频或多频测量,利用视频散率参数进行解释,野外测量工作量较大,测量精度相对较低。近几年,利用相位激发极化法在科研、生产中做了一些工作,这里介绍相位激发极化法模型试验及数据反演结果,岩矿石标本时间域(充电率)和频率域(相位)测试对比结果,以及实际应用实例及数据反演结果。应用结果表明,用相位激发极化法在矿产勘查中可以取得较好的勘察效果,并能在今后的工作中发挥更大的作用。     

大直径灌注桩的桩身完整性检测

桩身完整性检测的目的是查明桩的完整性,查清缺陷及其位置,以保证工程质量,不遗留事故隐患。常用的高、低应变,声波透射法三种动力测试方法在大直径灌注桩中所具有的特性及三种测试方法互为验证、多角度的分析研究可综合评价桩身完整性。