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41.
The Clementine spacecraft orbited the Moon and acquired science data for 10 weeks in the Spring of 1994. During this time it collected global 11-band multispectral images and near global altimetry. Select areas of the Moon were imaged at 25 m/pixel in visible light and 60 m/pixel in thermal wavelengths. From these datasets a new paradigm for the evolution of the lunar crust emerged. The Moon is no longer viewed as a two-terrane planet, the Apollo samples were found not to represent the lunar crust as a whole, and the complexity of lunar crustal stratigraphy was further revealed. More than ten years later the Clementine datasets continue to significantly advance lunar science and will continue to do so as new measurements are returned from planned missions such as Chandrayaan, SELENE, and Lunar Reconnaissance Orbiter. This paper highlights the scientific research conducted over the last decade using Clementine data and summarizes the influence of Clementine on our understanding of the Moon.  相似文献   
42.
差分层析SAR是在层析SAR基础上发展起来的一种四维信息反演技术。它不仅实现了对雷达目标的三维分辨能力,同时可以获取目标的形变速率信息,可实现对目标方位-距离-高度-时间四维成像,这对实现城市基础设施动态形变监测、古建筑风险评估、重要工程安全监测等应用具有重要实际意义和价值。本文基于差分层析SAR成像原理,分析了成像处理过程中存在的问题,总结了差分层析SAR成像算法研究现状和特点;最后列举了差分层析SAR技术的主要应用领域,并对其技术发展趋势进行了展望。  相似文献   
43.
该文回顾了环境气象卫星可见光红外光学成像遥感仪器50多年的发展历程,从不同时期在轨运行的近百台 (套) 仪器中选择了12种作为代表,结合仪器功能性能技术指标和应用需求梳理分析了其历史发展脉络和主流业务发展趋势,并初步探讨了创新发展方向。50多年的发展可以分为3个阶段:早期探索20年, 美国第1代探索性仪器,开创了气象卫星对地观测的先河;初步应用20年, 基本形成初步应用格局,欧洲、中国等开始发展自己的环境气象卫星光学成像遥感仪器;稳定应用和进步发展10多年。新一代极轨卫星可见光红外光学成像遥感仪器,其典型特征是光谱波段20个以上,谱段带宽窄,光谱范围全面覆盖0.4~15 μm,辐射测量精度高,空间分辨率为200~1000 m,其改进型仪器代表了未来极轨气象卫星主流业务发展趋势。静止气象卫星可见光红外光学成像遥感仪器未来主流业务发展方向的典型特点是光谱波段15个以上,谱段带宽较窄,光谱范围全面覆盖0.4 ~15 μm,辐射测量精度高,空间分辨率为500~2000 m,圆盘图成像速度可达到分钟级,区域扫描速度更快。  相似文献   
44.
龚珍  董恒  胡友健 《测绘科学》2016,41(4):93-96
针对传统的地面观测方式很难全面掌握城市地面热岛的空间分布情况的问题,该文将HJ-1B卫星热红外图像代表的亮温图和采用HJ-1B卫星反演的温度图像正规化,利用量化等级体系对同一地区的亮温分布图和温度分布图进行划分,提出并采用间隙度指数对不同影像的高温区进行空间分布进行评价。实验结果表明:基于热红外影像的城市热岛空间分布比基于热红外影像反演的温度图的热岛空间分布更为集中,为研究不同影像之间的城市热岛空间分布提供了一种评价方法。  相似文献   
45.
Seeing the ocean through the eyes of seabirds could help meet the challenges of managing common-pool marine resources both in protected and unprotected areas. First, seabirds are top-predators, exposed to all threats affecting the oceans, and this makes them ideal sentinel organisms for monitoring changes within marine ecosystems. Second, seabirds cross both ecological and political boundaries, and following their movements should help making interdependencies within and between marine ecosystems more visible. Third, seabirds are conspicuous and often charismatic animals, which interact differently with different groups of stakeholders and provide the opportunity to acknowledge and discuss each other's values and interests. In this paper, we present these research avenues using a seabirds’ view, for tackling marine conservation and management issues, and we give operational examples of implementation based on our work in the English Channel.  相似文献   
46.
为了验证位场偏移快速成像方法的有效性以及对比基于重力和重力梯度数据的偏移成像的效果,笔者利用MATLAB编写了重力及重力梯度数据位场偏移成像的算法,并进行了模型正演计算,发现基于梯度数据的偏移成像的横向分辨率、抗噪性和抗背景场能力好于重力数据的偏移成像,并且能够较好的确定模型的中心埋深。将此方法应用于葫芦岛市黑鱼沟的某铅锌矿洞的深度计算中,验证了该方法的有效性。  相似文献   
47.
如何从脑活动数据中发现具有生物学意义的知识及规律,正成为当今神经信息学理论与实践研究的热点与难点.基于脑电的情绪识别和情绪及其脑机制的关联研究已经成为神经工程和生物医学工程领域的热门课题.本研究基于脑电信号评价情绪状态,尝试借助脑电耳机来监测"毫无头绪"的脑电波,重点开展了听觉激励对改善焦虑情绪状态的实验研究.借助特定中国古风纯音乐产生听觉信号激励,激发出被试者平静放松的情绪状态,从而改善焦虑,发现音乐和情绪之间可能存在的关系.将来在BCI技术研究的基础之上,情绪识别可以进一步满足患有特定疾病(ALS症、脑瘫、脑干中风、脊髓损伤等)的患者人群的某些更高级的需求,即通过脑电分析出其对事物的喜好度,比如音乐的选择,从而设计出更加友善和智能的BCI系统,在医疗康复领域具有很好的应用前景.  相似文献   
48.
A three-dimensional thermo-mechanical coupled finite element model is built up to simulate the phenomena of dynamical contact and frictional heating of crack faces when the plate containing the crack is excited by high-intensity ultrasonic pulses. In the finite element model, the high-power ultrasonic transducer is modeled by using a piezoelectric thermal-analogy method, and the dynamical interaction between both crack faces is modeled using a contact-impact theory. In the simulations, the frictional heating taking place at the crack faces is quantitatively calculated by using finite element thermal-structural coupling analysis, especially, the influences of acoustic chaos to plate vibration and crack heating are calculated and analysed in detail. Meanwhile, the related ultrasonic infrared images are also obtained experimentally, and the theoretical simulation results are in agreement with that of the experiments. The results show that, by using the theoretical method, a good simulation of dynamic interaction and friction heating process of the crack faces under non-chaotic or chaotic sound excitation can be obtained.  相似文献   
49.
Microseismic systems at five mines in the Sudbury Basin provide the basic data for Falconbridge Limited's rockburst research. Daily and long-term analysis of this data as well as underground observations have confirmed the fault-slip mechanism at three mines. A detailed analysis of the complete history of Falconbridge Mine is being conducted and Distinct Element numerical models are being used to simulate both the stick-slip behaviour of faults and the dynamic effects of the induced vibrations on rock and backfill. University research includes acoustic tomographic imaging of the rock mass based on seismic wave propagation and collection of full microseismic waveforms to allow application of advanced seismic and statistical analysis techniques.Formerly with Mines Technical Services, Falconbridge Limited, Sudbury Operations, Falconbridge , Ont., P0M 1S0.Presented at the Fred Leighton Memorial Workshop on Mining Induced Seismicity, Montreal, Canada, August 30, 1987.  相似文献   
50.
The progress made on three phases of a research project, started in 1986 to investigate mining induced seismicity/rockburst phenomena using concurrent geotomographic imaging and microseismic monitoring techniques, is described. Phase I is the geotomographic software development and laboratory calibration trials. Phase II is the enhancement of traditional microseismic monitoring instrumentation with a waveform acquisition system, so that source mechanism studies can be carried out on mining induced seismic events. Phase III is the field trials of the hybrid technique which will be used to monitor changing rock mass physical properties, in response to mining. Preliminary results from all three phases are given, together with an outline of current and future research planned.Presented at the Fred Leighton Memorial Workshop on Mining Induced Seismicity, Montreal 1987.  相似文献   
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