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31.
The second Advanced Technology Microwave Sounder(ATMS) was onboard the National Oceanic and Atmospheric Administration(NOAA)-20 satellite when launched on 18 November 2017. Using nearly six months of the earliest NOAA-20 observations, the biases of the ATMS instrument were compared between NOAA-20 and the Suomi National PolarOrbiting Partnership(S-NPP) satellite. The biases of ATMS channels 8 to 13 were estimated from the differences between antenna temperature observations and model simulations... 相似文献
32.
本文采用一种复经验正交函数分析方法和滤波技术,对1978—79年冬季全球冬季风实验资料系列FGGE-Ⅲb进行分析,尤其对东亚地区时间尺度10—20天的主要行星尺度环流分量进行分解,结果表明影响气压和厚度场的决定性因子是冷季风潮,受季风潮影响200百帕上无辐散风u_φ第一模态以1—2天滞后沿经向和纬向有类似于季风潮的传播;季风潮振动导致局地经向环流相应变化,以无旋风V_X第一模态表示的Hadley环流几乎无经向传播但有明显的纬向传播,并在传播过程中加强;热带对于副热带存在反馈并通过u_φ第二模态实现。在急流入口处u_X第二模态表示次级环流的存在,其水平尺度约20个纬距。 相似文献
33.
34.
We report here results from a study of X-ray bursts from 3 magnetar candidates (SGR 1806-20, SGR 1900+14 and AXP 1E 2259+586).
We have searched for a pulse phase dependence of the X-ray burst rate from these sources. X-ray light curves were obtained
with the Proportional Counter Array on-board the Rossi X-ray Timing Explorer during the periods of intense burst activity
in these sources. On detailed analysis of the three sources, we found a very significant burst rate for all pulsar phases.
However, some locations appear to produce bursts slightly more often, rendering the non-isotropic distribution. Only in the
case of SGR 1900+14, there is a clear pulse phase dependence of burst rate. 相似文献
35.
Equilibrium trading of climate and weather risk and numerical simulation in a Markovian framework 总被引:3,自引:3,他引:0
Sébastien Chaumont Peter Imkeller Matthias Müller 《Stochastic Environmental Research and Risk Assessment (SERRA)》2006,20(3):184-205
We consider financial markets with agents exposed to external sources of risk caused, for example, by short-term climate events
such as the South Pacific sea surface temperature anomalies widely known by the name El Nino. Since such risks cannot be hedged
through investments on the capital market alone, we face a typical example of an incomplete financial market. In order to
make this risk tradable, we use a financial market model in which an additional insurance asset provides another possibility
of investment besides the usual capital market. Given one of the many possible market prices of risk, each agent can maximize
his individual exponential utility from his income obtained from trading in the capital market, the additional security, and
his risk-exposure function. Under the equilibrium market-clearing condition for the insurance security the market price of
risk is uniquely determined by a backward stochastic differential equation. We translate these stochastic equations via the
Feynman–Kac formalism into semi-linear parabolic partial differential equations. Numerical schemes are available by which
these semilinear pde can be simulated. We choose two simple qualitatively interesting models to describe sea surface temperature,
and with an ENSO risk exposed fisher and farmer and a climate risk neutral bank three model agents with simple risk exposure
functions. By simulating the expected appreciation price of risk trading, the optimal utility of the agents as a function
of temperature, and their optimal investment into the risk trading security we obtain first insight into the dynamics of such
a market in simple situations.
相似文献
Peter ImkellerEmail: |
36.
甘肃马泉金矿二十号矿带地质特征 总被引:5,自引:0,他引:5
通过对二十号矿带与矿床主体三、四号矿带地质特征的对比和ZK4 0 1孔伴生元素特征的研究 ,认为二十号矿带是四号矿带东延部分 ,其露头位于矿体头部附近。预测在二十号矿带180 0m标高以下一定还有较大盲矿体存在。 相似文献
37.
利用长江流域107个气象站1951-2000年的20cm口径蒸发皿逐日蒸发资料,采用Mann-Kendall趋势检验法和IDW反距离权重空间插值法分析了近50年来,尤其是20世纪90年代长江流域的年和季节蒸发皿蒸发量的时空变化.50年来,长江流域以年平均、夏季和秋季蒸发皿蒸发量显著下降为主要特点,尤以20世纪90年代最为显著,是年平均和夏季蒸发皿蒸发量最小的时期,比前0年平均值分别低-25.9mm和-36.1mm,这种趋势中下游地区比上游地区明显得多,尤其是在鄱阳湖流域. 相似文献
38.
Hans Knippenberg 《GeoJournal》1998,45(3):209-220
The Netherlands is one of the most secularized countries in the western world. The aim of this paper is to put the secularization
process in both historical and geographical perspective. As a mass process secularization started in the last quarter of the
nineteenth century and accelerated from the sixties of this century onwards. The first concentrations of non-denominationalism
could be found in the (Protestant) countryside of Friesland and Groningen as a consequence of profound social cleavages. Then,
the big cities in the west took part in the process and more recently even the Catholic areas were affected due to the cultural
revolution of the sixties and early seventies. Two counterforces were analysed: a religious revival within the Protestant
community and the increasing proportion of Muslims and Hindus as a consequence of immigration and high fertility levels.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
39.
Tinney 《Monthly notices of the Royal Astronomical Society》1998,296(4):L42-L44
Observations are presented which show that Li I λ 6708 is detected with an equivalent width of 0.53 ± 0.05Å in the proper-motion object LP 944-20 (which is also known as BRI 0337-3535). Hα is detected in emission at an equivalent width of 1.2 ± 0.5Å. The detection of Li implies a mass less than 0.065 M⊙, making this object a brown dwarf. Moreover, the relative weakness of this Li detection (compared to the equivalent widths of 1–2Å seen in objects of similar spectral type in the Pleiades) implies that Li has been somewhat depleted. This, together with the precisely determined luminosity of LP 944-20, implies a mass between 0.056 and 0.064 M⊙, and age between 475 and 650 Myr. This makes it the first brown dwarf to have a well-constrained mass and age determined. 相似文献
40.
P. Lamboit 《The Photogrammetric Record》2002,17(100):601-614
The Photogrammetric Society was formed in 1952. The Council of the Society considered that the twentieth anniversary was a good point at which to record the events which led to its formation and the significant occasions and decisions which have taken place since 1952. Consequently, Paul Lamboit was invited to compile this History. He has placed the birth and development of the society within the national and international photogrammetric context and his record of the deliberations which took place between 1947 and 1952 will be of particular interest to historians of our subject.
This account was first published in a limited edition in 1971. Sufficient interest has since been expressed to prompt a wider circulation through publication in the Photogrammetric Record .
The author served the Society continuously in several official capacities from 1953 to 1969 and he was elected to Honorary Membership in 1969. 相似文献
This account was first published in a limited edition in 1971. Sufficient interest has since been expressed to prompt a wider circulation through publication in the Photogrammetric Record .
The author served the Society continuously in several official capacities from 1953 to 1969 and he was elected to Honorary Membership in 1969. 相似文献