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1.
生态环境遥感分类数据矢量化方法与应用 总被引：4，自引：2，他引：2
遥感分类数据矢量化建库是生态环境遥感制图及其应用分析过程中主要的处理内容和基础工作。以福建省海岸带生态环境遥感分类数据为例 ,在分析遥感图像处理系统对遥感分类和专题信息提取后处理中矢量化能力不足和结果存在严重缺陷的基础上 ,综合应用遥感和地理信息基础软件平台 ,提供的系列数据管理、分析和数据转换功能模块 ,开展基于生态环境遥感影像分类数据的矢量化建库技术探讨 ,提出一个生态环境遥感分类数据矢量化建库的通用技术方法和流程 ,并对矢量化结果做了一个简要的评价和分析 ,以满足大面积生态环境遥感调查、分析和制图的实际需要。 相似文献
2.
遥感影像理解智能化系统与模型集成方法 总被引：11，自引：0，他引：11
智能化遥感影像分析理解是当前遥感地学分析中的研究热点。本文通过分析当前智能化方法在应用中存在的两个主要问题,指出了智能化遥感影像分析向基于多特征单元为分析对象转变的必要性以及如何在分析过程中更好的融合知识。在此基础上,介绍了多特征单元遥感影像分析和基于神经网络的知识处理的基本思想。并对如何建立基于知识智能计算的多特征单元遥感影像分析理解方法体系进行了探讨,给出了概念框架图。 相似文献
3.
苏红波 《地球信息科学学报》2002,4(3):91-91
本文从全球变化研究的需求分析入手 ,分析了地表通量遥感估算的重要科学意义 ,讨论了地表通量遥感过程中面临的几个关键问题 ,构建了地表通量遥感估算系统。对二层蒸发模型中的植被和土壤表面温度分解提出了可视化解算的思路。对遥感真实温度中的等效比辐射率 ,尝试利用蒙特卡罗方法进行计算 ,并对几种特定空间分布 ,特定类型树冠森林的四分量的方向性特性进行了详尽的分析。遥感反演地表真实温度 ,土壤和植被表面温度的分解是地表通量遥感中的关键步骤。 相似文献
4.
文章分析了辐谢源、大气层、地球表面、遥感器等对遥感信息的影响,并介绍遥感数据的特征,指出了遥感数据的局限性。 相似文献
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无人机遥感众创时代 总被引：2，自引：0，他引：2
当代科技发展降低了无人机和遥感器的准入门槛。大众参与为无人机遥感领域注入了巨大的创造力,触发了无人机遥感创新发展的爆发式增长。当前,无人机已成为普适化和平民化的科学手段,无人机遥感数据在众多领域和部门呈现出取代通航遥感和卫星遥感数据的趋势。本文首先对无人机遥感所处的时代特征及其展现的科技特色进行了分析与归纳,然后列举了无人机遥感在抗震救灾、岛礁测绘、极地科考、精准农田管理等领域开展的典型应用,最后从无人机发展所致遥感数据供应结构性调整、无人机遥感地理学研究推动、遥感无人机试验场地布局等方面进行了展望。特别地,针对无人机遥感应用量大面广、数据分布多源异构等特点,本文提出了无人机遥感数据航母的概念。 相似文献
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作为一代科学宗师,陈述彭先生是我国遥感地学分析的先驱、是遥感应用研究的开创者,陈述彭先生的逝世,不仅是我国遥感界甚至整个科学界的一大损失。值此逝世一年之际,回顾陈先生开创和繁荣遥感事业的历程,深刻缅怀陈述彭院士在推动我国地理学、地图学、遥感应用、地理信息系统等学科发展中的卓越贡献,以表达我们对他的敬意。 相似文献
9.
以图像处理和分析理论为依据,建立了云团、云影图像模型和区域恢复模型,并采用阈值法对图像分割。用1988年TM遥感影像对2002年ETM遥感影像中云团及云影进行去除试验,再现云团和云影区地物特征,提高遥感影像数据的可用性。结果表明,使用阈值法并利用直方图形态分析选取阈值、检测云团和云影的计算方法简单且效果好;选取合适的两遥感影像灰度平均值之比,可以得到理想的恢复效果,再现云团和云影区地物特征,达到提高遥感影像的可用性。 相似文献
10.
卫星遥感图像空间分辨率适用性分析 总被引：13，自引：0，他引：13
从卫星遥感图像空间分辨率的定义出发,简述了影响卫星遥感图像空间分辨率的几种因素。根据各研究领域和研究层次对卫星遥感空间分辨率的不同需求,给出其相应的空间分辨率。从测绘制图的角度确定了不同比例尺地图所需要的卫星遥感图像空间分辨率大小。讨论了当前主要遥感信息源的应用范围,并结合案例对其适用性进行了分析,最后指出了卫星遥感技术目前存在的一些问题,提出了几点看法。 相似文献
11.
《中国海洋大学学报(英文版)》2015,(4)
Hydroxyethyl chitosan(HE-chitosan) is a water-soluble derivative of chitosan with many apparent biological properties. For example, it is non-toxic and rapidly biodegradable. Moreover, HE-chitosan has advantages in water-solubility, moisture retention and gelling property due to its hydroxyethyl group. However, the biocompatibility and biodegradability of this multifunctional derivative have rarely been documented although they are critical for its application in biomedical and clinical treatments. The purpose of this work was to evaluate the biosafety of HE-chitosan, and draw important clues for its diverse applications. HE-chitosan was synthesized and characterized its chemical structure with FTIR. Its molecular weight(MW) was determined by gel permeation chromatography(GPC), and its deacetylation degree(DD) was investigated through potentiometric analysis. The cytotoxicity of HE-chitosan on mouse fibroblast cell L929 was tested. The biocompatibility and biodegradability of HE-chitosan in rat and rabbit were evaluated. The FTIR results indicated that the hydroxyethyl groups were linked to C6 of chitosan. The GPC analysis confirmed that its Mw was about 90.01 k Da. It was also demonstrated that HE-chitosan had excellent biocompatibility and biodegradability in vivo and had no cytotoxicity on L929. These findings indicated that HE-chitosan can potentially be applied as a biomaterial in tissue engineering, drug delivery, and other biomedical fields. 相似文献
12.
NEDHAM Mohammed Darsi 《世界地质(英文版)》2001,4(2)
AbstractYemen located on the southwest corner of the Arabian Peninsula. It is known that Yemen is important to world energy markets because of its oil and natural gas resources as well as its strategic location at the Bab el - Mandab strait linking the Red Sea and the Gulf of Aden. Due to the Ministry of Oil and Mineral Resources (MOMR, 1998E) the Yemeni Oil Production was estimated to be 385 000 barrels per day (bbl/d), Oil Consumption was 69 000 bbl/d and Net Oil Exports was 316 000 barrels per day (bbl/d). On 1999 the Yemeni Proven Oil Reserves was estimated to be 4 billion barrels and the Natural Gas Reserves was estimated to be 16.9 trillion cubic feet (Tcf) (Ministry of Oil and Mineral Resources, 1999). At this time, many researchers, scientific expeditions and foreign companies are interested in Yemen. This paper discussed the petroleum overview of the Republic of Yemen. In my opinion, Yemen is not just going to attract all with its oil and gas discoveries in the near future, but also with its new geological data and information. 相似文献
13.
为了鉴定杂交种子与父母本的亲缘关系,用20条随机引物和21条ISSR引物在供试的一组三系杂交水稻F1、父母本及对照进行扩增。20条RAPD引物共扩增出78个条带,其中28条为多态性条带;21条ISSR引物共扩增出72个条带,其中多态性条带为20条。将这些多态性条带进行聚类分析,F1与父、母亲缘关系较近归为一类,随后它们才与对照归为一类。结果表明RAPD和ISSR引物的PCR扩增均能有效地鉴定三系杂交水稻的杂种F1与组合中父、母本的遗传关系。与RAPD相比ISSR引物在三系杂交水稻及其父母本的鉴定中具有稳定性更好的优点。 相似文献
14.
Seasonal variations of several main water masses in the southern Yellow Sea and East China Sea in 2011 总被引：2，自引：1，他引：2
Qi Quan Xinyan Mao Xiaodan Yang Yingying Hu Haiyan Zhang Wensheng Jiang 《中国海洋大学学报(英文版)》2013,12(4):524-536
The seasonal variations of several main water masses in the southern Yellow Sea (SYS) and East China Sea (ECS) in 2011 were analyzed using the in-situ data collected on four cruises. There was something special in the observations for the Yellow Sea Warm Current (YSWC), the Yellow Sea Cold Water Mass (YSCWM) and the Changjiang Diluted Water (CDW) during that year. The YSWC was confirmed to be a seasonal current and its source was closely associated with the Kuroshio onshore intrusion and the northerly wind. It was also found that the YSCWM in the summer of 2011 occupied a more extensive area in comparison with the climatologically-mean case due to the abnormally powerful wind prevailing in the winter of 2010 and decaying gradually thereafter. Resulting from the reduced Changjiang River discharge, the CDW spreading toward the Cheju Island in the summer of 2011 was weaker than the long-term mean and was confined to flow southward in the other seasons. The other water masses seemed normal without noticeable anomalies in 2011. The Yellow Sea Coastal Current (YSCC) water, driven by the northerly wind, flowed southeastward as a whole except for its northeastward surface layer in summer. The Taiwan Warm Current (TWC) was the strongest in summer and the weakest in winter in its northward movement. The Kuroshio water with an enhanced onshore intrusion in autumn was stable in hydrographic features apart from the seasonal variation of its surface layer. 相似文献
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The huge comendite ignimbrite- forming eruption of Tianchi Volcano maintained a stable plinian column during its earlier stage of eruption, and succeeded a collapsing of the column producing pumiceous ignimbrite deposits. It is estimated that the column height (Hb) varied from 20km to 10km in its eruption period, with a maximum height of 25km in the eruption peak. Its umbrella cloud spread into the stratosphere with a top height of 35km (Ht). The dense lithics whose diameter exceeded 8cm followed a ballistics trajectory in a 3km - high gas thrust region, while the smaller lithics and pumices entered the convection region in the column. The initial magma temperature was 780℃. The comendite magma had an exit velocity of 300m/s, volatile content of about 1wt% and lithics of 8.5wt%. From a 400m - wide vent the magma was expelled out with a mass eruption rate of 108.36kg/s, corresponding to a volume rate of 104.95m3/s. Over 1. 3436 × 1019J of energy had been released from Tianchi Volcano, of which the kinetic proportion was about 8 %. The plume had a temperature of -50℃ at the base focus of the cloud and a upward speed of 215m/s. The cloud spread out at a gradually downspeed with the increasement of distance from its center. For example, at a distance of 25km from its center the spreading velocity is about 250m/s, and is about 60m/s at distance of 100km. The main part of the plinian column, that is the convection region, once occurred in the height between 3 to 25km, and its maximum width was about 13km in radius. 相似文献
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一前言在国际上,透辉石虽尚未列入工业矿物范畴,但1975年西德首次报导了合成透辉石在釉面砖、卫生瓷、日用瓷方面应用的试验研究文章。继后,1984年苏联在《玻璃与陶瓷》的杂志中报导了“天然透辉石产物—一种有前途的陶瓷原料”。随着研究工作的不断深入,透辉石的应用领域不断扩大,除主要应用于陶瓷工业外,在硅微晶玻璃、铸石、各种油漆、颜料、涂料领域里也得以广泛应用。 相似文献
17.
On May 12, 2008, an earthquake of 8.0 magnitude on the Richter scale and its numerous aftershocks devastatingly hit Wenchuan
County and its nearby region along the Longman Mountains in Sichuan Province, China. The heavy ruined area was up to 30,000
km2 and 13% of its land surface was denuded by the extremely terrible quakes. The mountain collapses, landslides and debris
flows induced by the earthquake not only scared the landscape at the immense scale, but also poured 1.66-billion-m3 sediment
combined with offscourings and rubble into the Yangtze River and its breaches. This amount of sediments is 3 times more than
the normal amount discharged into the Yangtze River, and will significantly increase sediment transportation of rivers and
decrease storage capacities of reservoirs downstream. The dramatic increase in sediment load will imperil the engineering
safety and impact the operation of the giant Three-Gorge Hydro-power Station if no proper prevention measures are taken. 相似文献
18.
黎志敏 《广东海洋大学学报》2008,28(2):89-94
中国新诗创立具有一定的诗学因素,诗人们难以在传统诗歌领域推陈出新。在其理论并不成熟,而且没有生产出优秀作品的前提下,新诗主要是作为新文化运动和白话文运动的一分子被人们所接受,并且迅速确立其社会地位。新诗在几十年的发展过程中也一直具有强烈的社会与政治关怀。在20世纪90年代之后,新诗逐渐放弃社会责任,企图回归艺术。可是新诗的艺术成就本来不高,放弃社会责任对于新诗来说其实是放弃了存在的主要理由。摆在新诗面前的是一条漫长的艺术探索之路,成功与否直接关系到新诗最终的成败。 相似文献
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The. rates of glucose uptake by some species of plankton were determined by 3H-glucose tracer method. Experimental results indicated that the observed glucose uptake at natural sea water concentrations by Platymonas subcordiformis and Brachionus plicatilis was principally a metabolic process fitted with the Michaelis-Menten equation in the range of adaptive temperatures. Heterotrophic uptake by Platymonas subcordiformis was mainly dependent on diffusion at high glucose levels. The uptake by Brachionus plicatilis showed active transport even at high glucose levels, indicating its high heterotrophic activity. The uptake rate by Anemia salina was lower, and its Vm/K ratio was lower than those of the other two species of plankton. 相似文献
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本文根据小浪底水库地区的地震地质和水文地质条件，浅析了水库诱发地震的可能性，并对其最大震级进行了多种方法的估算预测。 相似文献