无源微波遥感海上石油污染的研究

本文应用空气、油膜和海水组合体模型计算和分析了有效发射率随油膜厚度、工作频率和入射角变化的关系,提出了无源微波遥感海上石油污染的优选方案并成功地进行了航空微波遥感试验。     

STUDY ON PASSIVE MICROWAVE REMOTE SENSING OF OIL POLLUTION ON SEA SURFACE

By using the model of air-oil slick-sea water system, the influence of the oil slick thickness, operating frequency of the radiometer and incidence angle on the effective emissivity are calculated and analysed. The optimum scheme for passive microwave remote sensing of oil pollution on sea surface is also proposed and used successfully for airborne microwave remote sensing experiments.     

Microwave Radiometry for Oil Pollution Monitoring, Measurements, and Systems

Work is presently carried out in Europe to change the Status of the microwave radiometer, namely, to develop it from a research instrument to an operational instrument-especially for measuring oil pollution on the sea surface. The Technical University of Denmark (TUD), with its long experience in airborne microwave radiometry, is heavily involved in this process. The TUD multichannel imaging radiometer system has been flown in several large-scale oil-pollution experiments, the collected data have been analyzed, and they have revealed that care must be exercised to obtain accurate oil volume estimations. Computer simulations of the total measurement situation have shown how the observed difficulties come about and have indicated the countermeasures to apply. Based on the above-mentioned exercises, optimum (and practical) systems are being developed.     

小型高光谱图谱仪与激光雷达及其海洋应用

海洋是地球生态环境的重要一环,但人类对海洋资源的勘探和开采容易对其造成严重破坏,如油气开采过程造成的大面积溢油、污染和赤潮爆发等。高光谱成像技术可以同时获取图像信息与高分辨光谱信息,在海洋原位探测上具有重大应用。文中综述了小型高光谱图谱仪与激光雷达及其在海洋应用上的部分近期工作。小型高光谱图谱仪结合荧光技术,实现了溢油种类的分类和油膜厚度的估计。多模式高光谱海洋原位探测系统可以工作于普通反射或透射成像、望远成像、显微成像三种模式,实现了海洋不同藻类及鱼类传染病载体孢囊的高光谱探测。高光谱技术结合激光雷达技术在溢油、赤潮等海洋污染物监测方面具有很大潜力。非弹性高光谱沙姆激光雷达系统通过油品的荧光光谱实现了海洋溢油油品的遥测鉴别。形貌沙姆激光雷达系统基于二维沙姆成像原理,通过空气-水界面折射矫正,成功的对人体、贝壳、珊瑚等进行了三维形貌重构,近处恢复精度可达毫米级,表面纹路清晰可见,为海洋监测应用提供了新的技术支持。     

L波段微波辐射计周期脉冲式干扰时域检测方法研究

L波段微波辐射计是探测土壤湿度和海水盐度的有效遥感器。但是,全球定位系统(GPS)信号、雷达信号以及一些商用电子产品的电磁辐射造成的频谱污染都可以对微波辐射计的探测造成干扰,使得被动微波遥感对地观测结果具有一定的偏差,降低了地表参数的反演精度。该文通过实验模拟脉冲式噪声干扰,观测其在L波段(全功率接收型式)微波辐射计系统中的传输特性,分析输出信号特性与辐射计参数(积分时间、灵敏度)的相关性,获取其数字特征参数,结合脉冲检测法(APB),提出一种新的自相关检测(ACD)算法,能够有效用于周期性的脉冲式辐射干扰的检测,在微波辐射计系统积分时间1 ms的情况下,能够检测1.5 K的噪声干扰,满足卫星遥感探测反演地表参数精度的需求。     

差分偏振FTIR光谱法探测水面溢油污染的模型分析

海上溢油污染严重危害着海洋生态环境,为了能够及时了解某一水域的溢油污染程度以及溢油的种类,提出了差分偏振傅里叶变换红外(FTIR)光谱法遥感水面溢油.通过获取分析目标在水平和垂直两个偏振方向的偏振强度差谱,对水面油膜实现了直接探测,并且通过分析差分偏振FTIR光谱中的光谱特征,可以识别水面溢油的种类,弥补了传统热红外遥...     

Microwave radiometry: its importance to the detection of cancer

The author discusses developments in the medical uses of microwave radiometry, particularly in relation to the early detection of cancer, as well as the significance of and progress in related antenna technology. In the treatment of cancer, microwave hyperthermia is accepted as an adjunct to radiation therapy in the treatment of superficial lesions. Although not as widely reported, the use of microwave radiometry as a noninvasive, passive technique for the early detection of cancer appears promising. Wider acceptance of these methods, however, awaits fundamental improvements in the ability to focus energy at depth in human tissue, an important and nontrivial antenna problem. Antenna development is described, and the improvements required if microwave technology is to provide a practical solution to the detection and treatment of cancer are indicated     

合成孔径雷达海面溢油探测研究进展

海洋溢油污染不仅严重威胁海洋生态安全、破坏海岸带环境,而且直接和间接地影响着广大人民群众的生活和健康以及区域社会经济的发展。合成孔径雷达因其具有全天候和高灵敏度的观测能力而成为海面油膜探测的主要手段之一。该文从SAR海面油膜探测的基本原理出发,介绍了单极化、全极化和紧缩极化SAR海面油膜探测技术的国内外最新研究进展,对该技术手段在实际应用中遇到的主要困难和挑战做了深入分析,最后总结展望了该技术未来发展的广阔前景。     

油砂沥青含油污水微波作用效果实验研究

本文主要实验研究加拿大油砂沥青含油污水微波破乳除油效果。在其他外界条件相同的情况下,采用单因素变量法研究了微波功率、作用温度和不同的工艺组合等对微波破乳除油特性的影响,探索微波结合其他处理工艺对污水的除油效果。实验研究表明,功率越大,除油率越高。微波作用温度则存在最佳温度范围。微波结合离心和过滤将有效增加除油速率,除油率达70%左右,污水中添加絮凝剂再经微波作用后的除油率超过了90%,处理后的污水含油量可达到污水排放标准。     

Ocean Experiments And Remotely Sensed Images of Chemically Dispersed Oil Spills

A series of experiments was performed at sea where the effectiveness of dispersants applied from a helicopter was tested on fresh and weathered crude oils released from a surface research vessel. In conjunction with these experiments, remote sensing measurements using an array of airborne optical and microwave sensors were performed in order to aid in the interpretation of the dispersant effectiveness and to obtain quantitative images of oil on the sea under controlled conditions. Surface oil thickness and volume are inferred from airborne measurements using a dual-channel microwave imaging radiometer, aerial color photography, and an airborne oceanographic lidar. The remotely sensed measurements are compared with point sampled data obtained using a research vessel. The mass balance computations of surface versus subsurface oil volume using remotely sensed and point sampled data are consistent with each other and with the volumes of oil released. Data collected by the several techniques concur in indicating that, for the oils used and under the sea conditions encountered, the dispersant and application method are primarily useful when applied to fresh oil.     

复杂天气及海风对天基被动干涉微波辐射无源探测系统性能的影响

基于微波辐射无源探测系统的目标探测方程,该文探讨了云、雾和雨等复杂天气以及海风对天基被动干涉微波辐射无源探测系统的影响,定量化仿真分析了这些因素对系统探测能力的影响,实验验证了被动干涉微波辐射无源探测系统对云层的穿透能力。研究结果表明:云、雾和雨等复杂天气对被动干涉微波辐射无源探测系统对海面目标的探测有一定的影响,但在低频段云雾影响较小,可忽略不计;而降雨会对系统的目标探测能力影响较大;海风对海面金属目标的探测是有利的,而海风对隐身目标探测是不利的,会降低系统的探测能力。     

油气管道缺陷检测技术综述

油气管道泄漏将会造成巨大的经济损失和环境污染,因此,需要采用管道缺陷检测相关技术来定期对管道进行缺陷检测,最终达到对油气管道的保修和维护目的.本文首先归纳了油气管道缺陷检测技术演进过程,然后从申请人和申请量的角度进行了专利分析.     

微波辐射对稠油粘度的影响

利用微波的特殊加热机理对苏丹、委内瑞拉等劣质原油进行微波辐射作用,考察微波作用前后原油粘度变化情况。通过改变微波作用时间、作用功率,考察微波作用对原油粘度影响规律。同时考察微波作用对原油物性及组成的影响。在微波作用过程中考察原油含水对微波辐射降粘效果的影响。结果表明：微波对不同原油作用效果不同,原油含水对微波场的吸收有重要影响。     

基于统计窄谱带模型的油料火焰辐射光谱模拟

近年来油料火灾污染事故频发危害性极大,通过分析光谱特性来提取火灾信息已成为研究油料火灾事故的重要途径.目前国内外学者已建立了多种气体辐射和炭黑辐射的模型对燃料燃烧进行研究,但少有对火焰光谱进行建模深入分析燃烧污染产物光谱特征信息.本文搭建了油料火焰光谱测试平台,测量了单一尺度下酒精、92号汽油、95号汽油和0号柴油的火...     

航天器用内螺纹的气体湍流激光多普勒式检测

为了解决航天器操纵旋转套筒内螺纹的自动检测问题，特别是在内螺纹件表面有油污与锈蚀时，单纯地利用光学图像检测的方法很难更好地解决问题，利用平流气体吹向内螺纹，从而形成了映射着内螺纹形貌的湍流输出，然后利用多普勒激光测量内螺纹的湍流特性。研究了内螺纹气体湍流的拉伸与压缩过程的数据特性，利用箱线图的方法处理内螺纹湍流数据，建立了内螺纹湍流箱线图的标准样板库，将检测数据与标准样板对比检测，结果表明:当异常值阈值设为7%时，检测准确率为99.3%。气体湍流激光多普勒式检测内螺纹方法可行，克服了表面油污等难点，完全满足检测的要求。     

高凝油微波降凝非热效应实验研究

对高凝油进行微波作用降凝效果研究。析蜡点、凝点和含蜡量是表征原油析蜡过程的重要参数。研究发现经过微波加热处理后,各高凝油的析蜡点、析蜡高峰、常温含蜡量和凝点均有不同程度的降低,高凝油的蜡晶颗粒聚结变大,凝点降低。实验进行了微波加热和水浴作用的对比,当微波和水浴作用原油到相同温度时,微波的作用效果更佳,实验研究结果表明微波降凝存在非热效应。     

A Microwave Method for Measuring Changes in Lung Water Content: Numerical Simulation

A numerical procedure to simulate several physiological and geometrical changes occurring during development of edema and to study their effects on the sensitivity of the microwave detection method is presented. The method of solution utilizes a model which consists of a two-dimensional cross section of a thorax. The model is based on an X-ray CAT scan taken with the microwave applicators in place. The electromagnetic boundary value problem is then solved numerically using the method of moments. Numerical results are presented to show the effects of several parameters, such as the uneven water distribution in the lung, the field distribution in the aperture of the microwave transmitter, and the location of the receiver on the sensitivity of the microwave detection method. Based on these results, several suggestions are made to help optimize the sensitivity of the microwave method of measuring changes in lung water content.     

电波环境及微波超视距传播

电波环境是信息化系统和武器装备的重要组成部分,微波超视距传播基于对流层电波环境中的大气超折射(大气波导)和散射机制,可实现数百千米的地基/岸基/船载雷达微波超视距远距离目标探测或无中继微波超视距远距离通信,具有较大的实际应用价值。文章介绍了电波环境的概念和数据要素、对流层大气波导和散射传播的特点以及微波超视距效应评估技术,在此基础上分析了微波超视距雷达探测技术的典型应用场景。     

Oil spill detection: imaging system modeling and advanced image processing using optimized SDC algorithm

Oil spill on the sea surface might happen without any previous caution and is seen relatively often. Efficient and effective oil spill monitoring and detection can reduce response time, minimize remediation costs and limit dangerous impacts to the environment. An innovative satellite-based oil pollution detection framework is demonstrated in this paper, including satellite imaging system modeling—communication link configuration, noise model for image transmission and preprocessing. Finally, an optimized sequential detection of change-based image object detection algorithm is proposed to detect oil spill on the ocean surface from the enhanced remote sensing data. Moderate resolution imaging spectroradiometer images of the Gulf of Mexico accident from NASA between May and June 2010 are adopted for testing in our framework. The results of this research show that the proposed algorithms can effectively distinguish the spill covering vast areas of the marine environment even with severe additive noise and have good separation properties against complex signatures, such as the vicinity to the irregular coast or foggy and cloudy weather conditions.     

微波辐射峰值吸收频率对原油组分的影响

利用微波辐射降低原油粘度是一种新的高效处理方法,微波降粘效果取决于油样吸收微波的能量,油样对微波的吸收率取决于微波频率,因此油样最大能量吸收率所对应的微波频率定义为峰值吸收频率。基于微波二端口网络模型,利用自行设计的微波辐射实验设备进行研究,精确测量了待测油样的峰值吸收频率,并详细分析了频率对原油组分的影响。结果表明:在3.9 ~6.5 GHz 的扫描频率下,油样在频率为5.8 GHz 时出现第1个吸收频率且能量仅剩69.9%,在6.2 GHz 时出现第2 个吸收频率且能量仅剩36.4%,该频率为峰值吸收频率;运用GCMS分析经过5.8 GHz 和6.2 GHz 微波辐射后,轻组分(C7-C14)分别增加了7.6%、8.7%,重组分(C16 及以上碳数)分别减少12.4%、13.5%,原油组分发生明显的改变。研究结论为微波辐射技术在石油行业运用提供了重要的参考,证明了该技术具有良好的应用前景。