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101.
胶莱盆地是胜利油田的探区之一,而姜山洼陷又是胶莱坳陷中重点的烃源岩发育区。自从1979年就开始了地震勘探,由于山地地表地下双复杂的地质条件限制,所获得的地震资料品质一直较差,制约着地震勘探的进一步开展。2006年在该区开展了地震勘探攻关,应用了宽线地震采集技术,取得了良好的效果。本文就宽线技术的使用效果进行了对比分析,总结了宽线地震采集技术在该地区的应用前景。 相似文献
102.
Sub-surface radar has become increasingly popular for carrying out completely non-invasive integrity tests on concrete structures. Commercial systems are available with a range of antenna frequencies that may be selected for an investigation. The choice of a particular antenna frequency is often a compromise between the physical size of the antenna and the penetration and resolution capabilities provided by the antenna. However, there is an interaction between a surface contact antenna and the substrate under investigation that will alter the field pattern being transmitted that may have significant implications for interpretation of results. An experimental programme is described in which the characteristics of commercially available 900 MHz and 1 GHz antennas are compared in air and when in contact with concrete and water surfaces, together with an emulsion used in previous studies to simulate the radar properties of concrete. Results are presented showing the influence of the material being measured upon the signal divergence. These effects are considered in terms of the practical implications for field-testing using radar. 相似文献
103.
一种高分辨雷达目标识别方法 总被引:2,自引:0,他引:2
研究了宽带高分辨雷达目标识别问题,基于目标一维距离像,提取目标散射中心特征,并根据该特征设计了简单目标的目标分类器,利用暗室测量得到的缩比模型高分辨回波数据进行识别,结果表明该识别方法具有良好的识别性能。 相似文献
104.
Michael Reilly 《半导体技术》2004,29(12)
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system. 相似文献
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107.
D—T2二维核磁共振能够快速、直观地区分不同性质、不同赋存状态的孔隙流体,已成为储层评价的热门技术,但对于页岩油储层,常规储层的D—T2孔隙流体解释图版并不适用,考虑受限扩散、内部梯度等影响因素的修正图版也难以满足页岩油储层油、水识别的要求。为此,采用理论分析与实验分析相结合的方法,对D—T2孔喉尺度分辨率、流体含量分辨率、孔隙流体解释图版3个关键要素进行了深入研究。结果表明,D—T2孔喉尺度分辨率、流体含量分辨率均低于T2一维核磁共振,难以检测到T2短于2 ms、含量低于0.2%的流体信号;D—T2信号位置与流体含量有关,且随着流体含量的递增,具有随机游走特性。2口页岩油井的应用表明,基于流体含量信号响应轨迹的D—T2流体解释图版能够实现页岩油储层的准确解释。 相似文献
108.
本文介绍了30mm~2和80mm~2大面积Si(Li) X射线探测器的研制工艺及测量中的部分问题,并作了讨论。80mm~2探测器的系统能量分辨率为173eV(对~(55)Fe 5.89keV Mn Kα X射线),该指标已达到国外同类产品的水平。 相似文献
109.
Although High Resolution X-ray Micro Tomography (HRXMT) has been developed in the past years for the 3D analysis of multiphase mineral particles in packed particle beds, image analysis of fine and/or high-density/high atomic number particles has been limited by existing segmentation algorithms. In this regard, a feature-based segmentation algorithm has been developed and demonstrated to provide a more accurate image processing method for the analysis of such multiphase particle populations. Based on this improved segmentation algorithm, image analyses of packed particle bed samples were compared to segmentation by traditional 3D watershed segmentation. Also, calculation of particle number using optical microscopy, together with a digital camera, was accomplished to validate feature-based segmentation. Detailed procedures and results for sample preparation, image analysis and validation are presented and discussed. 相似文献
110.
Despite the popularity of the analogue measuring devices, there is no recognized reference provided comprehensive guidelines for determining their resolution and its associated uncertainty. For filling this gap, this article is introduced as an attempt to explore and investigate all the available works related to this issue. The new terminology “evident space”, “evident resolution”, and “conjunction” were proposed to set a common reference. Two different techniques for determining the analogue resolution were presented and discussed. Several numerical examples were also presented to show different analogue indications and their interpretations. Moreover, reasonable recommendations for determining the resolution uncertainty were suggested depending on the case. 相似文献