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91.
Single Epoch GPS Deformation Signals Extraction and Gross Error Detection Technique Based on Wavelet Transform 总被引:1,自引:0,他引:1
WANG Jian GAO Jingxiang XU Changhui 《地球空间信息科学学报》2006,9(3):187-190
IntroductionGPS technique is widely used for deformationmonitoring thanks for the high precision. Usual-ly , there are three working modes associatedwith GPS deformation observation: periodicalGPS deformation monitoring net , GPS monito-ring array and rea… 相似文献
92.
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94.
刘耘 《矿物岩石地球化学通报》2007,26(1):49-51
用基于Urey模型的量子化学从头计算,揭示Fe在FeCN63-和FeCN46-中的不同“自旋态”对同位素分馏行为的巨大影响,说明了只考虑“价态”的做法是不正确的,修正了关于“重同位素倾向于富集在高价化合物中”的这个广泛被接受的基本原理。并首次指出在压力导致自旋态变化的地质过程中,必定存在同位素分馏反常的复杂状况,是值得进一步研究的方向。 相似文献
95.
南海的油气资源极为丰富,享有“第二个波斯湾”的美誉.南海地貌类型多样,地形复杂,其战略位置极为重要,是东亚及相邻各国必经之路.资源之争,使得周边各国使出浑身解数,发展海洋经济与技术,1981年至2002年,越南就从南沙海域的油田中开采了1亿吨石油、15亿多立方米的天然气,获利250亿美元,南海石油已成为越南国民经济的第一大支柱产业.近半世纪中国南海油气勘探工作取得巨大的成就,发现了26个新生代盆地,取得了南海海域的基本石油地质成果,为南海的勘探开发奠定了基础.南海具有巨大的勘探空间及技术发展空间,每一次的技术进步,都会带来南海油气勘探的质的飞跃. 相似文献
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97.
B.F. Iyun 《GeoJournal》1998,44(2):129-139
The viewpoint that most health problems are environmentally related has always been promoted by medical geography. In recent
times, concern about environmental degradation has been of high priority for many national and international organizations
as ‘we human beings become a threat to our planet’. There is also a need to specifically focus attention on the impact of
so-called development efforts on the health of women and children, in particular those living in highly marginalized regions
which often contribute substantially to the overall development of their countries.
This paper uses the concept of vulnerability as a departure point from which to map the health risks to children in Igbekun
area of Ondo State, the ‘transgressive muddy’ oil-rich coastal area of Nigeria. The paper attempts to highlight the poor quality
of life and health of children in particular, and how it is becoming much more difficult to practice health intervention programmes,
especially oral rehydration therapy (ORT) in the area.
The Igbekun area is an unhealthy and harsh environment, complicated by the devastating effects of oil drilling in recent years.
The siltation and sedimentation of the creeks and lagoons have serious health dimensions as human faeces float in and around
villages because the ‘bush toilets’ can no longer be reached. The on-going environmental crisis has also deprived women of
their traditional means of livelihood; fishing.
There is a relatively high level of ignorance (compared with other women living in the same local government area (LGA) of
causes of the commonest diseases such as diarrhoea, acute respiratory infection (ARI) and measles. A majority of the women
have never heard of family planning, immunization against diseases and interventions such as ORT. Promotive health care services,
especially those that strive to reduce the high mortality of children have passed the mothers by. It is also becoming impracticable
to promote ORT because of the widespread ‘salty and oily’ water supply in the area.
The greatest concern of the women now is that oil drilling activities have further amplified their stressful conditions especially
their health and that of their children. Unfortunately, their plight is not acknowledged by the Nigerian authorities and the
oil companies are least concerned about alleviating the poor health status of the community, in particular the most vulnerable
groups, children under the age of five.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
98.
Three provenances ofPappophorum caespitosum, a forage native grass from the temperate arid region of Argentina, were studied to gain a physiological knowledge of the seasonal organic N status in response to adequate water supply and water stress conditions; and to assess the extent to which variations in the N status between these provenances arise under different water regimes. Plant part samples were analysed for free and bound organic N fractions. Water shortage resulted in a significant depression of plant growth in all provenances. Total N concentration declined along the annual cycle in both water treatments, but it was higher under water stress. The size of the free N pool was very large, suggesting that it may act like an osmoticum. Nitrogen use efficiency increases along the growing period, while the rate of N intake and the specific leaf N content decrease. Variability was found between provenances in most of the physiological and biochemical traits examined under both water regimes. 相似文献
99.
九华山铜矿床中伴生金已具综合利用价值。金以矿物态为主,金矿物主要为银金矿、含银自然金。金矿物粒度较细,大于200目者占24.34%,金矿物主要嵌布于黄铜矿粒间或裂隙中。金的理想回收率为66.30%,空间分布上,沿矿体走向金西低东高,倾向金北高南低,深度金随深度增加而增加。 相似文献
100.
本项研究是PMIP(PalaeoclimateModelingIntercomparisonProject)国际合作项目中有关模型模拟与观测资料对比的一部分。模型试验对象是6000yr.BP的全球湿润状况。模拟试验以检测太阳辐射变化对全球大尺度气候系统的影响为主要目的。观测资料是利用地质证据恢复的古湖泊水位变化,实际上是某一地区的有效降水(降水减蒸发)的变化。通过两者的比较发现,所有模拟试验均能重现6000yr.BP在亚洲南部与非洲北部的湿润环境,从而证实了因太阳辐射变化导致的亚洲与非洲季风的增强。但模拟的季风增强无论是强度还是范围均小于地质记录。原因很可能是模拟试验中下垫面特征用“现代”的来处理。模拟试验对北半球夏季辐射增加造成的西风带北移及由此引起的中纬度地区的气候变化不够成功。绝大多数模拟对受洋流与海温影响较大的地区是失败的。主要原因可能是所有PMIP中的模拟试验都未考虑海洋的作用。 相似文献