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961.
利用GAMIT/GLOBK软件处理2011年特种监测网的观测数据,将IGS站的选取分10种方案进行试验,计算结果从基线长度变化、测站坐标、NRMS、基线重复率等方面进行了比较。得出利用GAMIT/GLOBK软件处理该特种监测网时的几点建议:建议选取IGS站为GPS网提供参考框架;IGS站选取的数量不一定最多,但空间上应尽量均匀分布;选取7个IGS站时得到较高精度的结果。在日后处理此类型的特种监测网时对IGS站选取具有一定的参考价值。  相似文献   
962.
以云的方式提供语音识别服务是1种新的趋势。当前市场上的语音云都是面向通用领域的,针对这一现状,提出了1种面向特定领域,可定制的,可满足用户个性化需求的云计算方案。首先介绍了语音识别的MapReduce过程,接着描述了基于Sector/Sphere的语音识别系统组成及语音识别的Sphere处理流程,并给出了语音识别系统的云计算架构,然后探讨了语音识别的可定制实现,最后进行实验评估,证明云计算架构的语音识别系统与传统C/S架构的语音识别系统相比更具优势,且具有一定的可扩展性。  相似文献   
963.
Changes in sea surface temperature(SST), seawater oxygen isotope(δ 18 O sw), and local salinity proxy(δ 18 O sw-ss) in the past 155 ka were studied using a sediment core(MD06-3052) from the northern edge of the western Pacifi c Warm Pool(WPWP), within the fl ow path of the bifurcation of the North Equatorial Current. Our records reveal a lead-lag relationship between paired Mg/Ca-SST and δ 18 O during Termination II and the last interglacial period. Similarity in SST between our site and the Antarctic temperature proxy and in CO 2 profi le showed a close connection between the WPWP and the Antarctic. Values of δ 18 O sw exhibited very similar variations to those of mean ocean δ 18 O sw, owing to the past sea-level changes on glacial-interglacial timescale. Calculated values of δ 18 O sw-ss refl ect a more saline condition during high local summer insolation(SI) periods. Such correspondence between δ 18 O sw-ss and local SI in the WPWP may refl ect complex interaction between ENSO and monsoon, which was stimulated by changes in solar irradiance and their infl uence on the local hydrologic cycle. This then caused a striking reorganization of atmospheric circulation over the WPWP.  相似文献   
964.
The diet of Pomatoschistus microps has been studied using both gut content and stable isotope analyses. In the Roscoff Aber Bay (Brittany, France), this fish is commonly found on sandy muddy intertidal flats. Gut content analyses were also interpreted using trophic indices. Owing to the large diversity of prey consumed, these indices emphasised the opportunistic feeding behaviour of P. microps. Here, this species fed mainly on endofauna with meiofauna being of high relative importance. The main biotic components of its trophic habitat, characterized by δ13C and δ15N, provided evidence of a major trophic pathway based on drift Enteromorpha sp. Trophic positions estimated by both diet analyses and isotopic analyses led to similar results. In this bay, P. microps is a first‐order predator with a low degree of omnivory. Despite a preferential consumption of the amphipod Corophium arenarium, we assumed that this goby behaves as a generalist feeding on a uniform variety of endofauna taxa.  相似文献   
965.
全球有效波高和风速的时空变化及相关关系研究   总被引:2,自引:1,他引:1  
The climatology of significant wave height(SWH) and sea surface wind speed are matters of concern in the fields of both meteorology and oceanography because they are very important parameters for planning offshore structures and ship routings. The TOPEX/Poseidon altimeter, which collected data for about 13 years from September 1992 to October 2005, has measured SWHs and surface wind speeds over most of the world's oceans. In this paper, a study of the global spatiotemporal distributions and variations of SWH and sea surface wind speed was conducted using the TOPEX/Poseidon altimeter data set. The range and characteristics of the variations were analyzed quantitatively for the Pacific, Atlantic, and Indian oceans. Areas of rough waves and strong sea surface winds were localized precisely, and the correlation between SWH and sea surface wind speed analyzed.  相似文献   
966.
Stable carbon and nitrogen isotopic composition of particulate organic matter(POM) were measured for samples collected from the Bering Sea in 2010 summer. Particulate organic carbon(POC) and particulate nitrogen(PN) showed high concentrations in the shelf and slope regions and decreased with depth in the slope and basin, indicating that biological processes play an important role on POM distribution. The low C/N ratio and heavy isotopic composition of POM, compared to those from the Alaska River, suggested a predominant contribution of marine biogenic organic matter in the Bering Sea. The fact that δ13C and δ15N generally increased with depth in the Bering Sea basin demonstrated that organic components with light carbon or nitrogen were decomposed preferentially during their transport to deep water. However, the high δ13C and δ15N observed in shelf bottom water were mostly resulted from sediment resuspension.  相似文献   
967.
传统的海冰检测手段都存在着受天气影响或实时检测成本太高的缺点,为了更实时有效的检测海冰,减轻海冰灾害对于我国的影响,并达到防灾减灾的目的,本文研究了GPS反射信号(GPS-R)技术检测海冰的可能性。通过对2013年2月下旬在中国天津渤海湾的岸基架设GPS信号接收机所接收的观测数据进行分析,使用不同特性的反射海域(几乎全为海水或是海冰)的数据进行比对分析,其结果显示极化比值(反射左旋信号与直射右旋信号的比值)能够明显反演海冰密集度。本文首次将GPS-R技术应用于国内自主设计的渤海海冰检测实验中。  相似文献   
968.
We studied diatom assemblages and CaCO3 contents of methane-derived authigenic carbonates from the eastern margin of the Sea of Japan and assessed the formation time of these samples. Radioactive 14C date was determined in selected samples to obtain the maximum age of the time. The results of our study suggest mass formation of carbonate nodules in a glacial period within ∼40 ky, consistent with a published U/Th dating result of carbonate nodules in the study area. Diatom assemblages and contents in the carbonate nodules (abundance of ∼106/g, dominance of neritic-littoral species, warm/cold water species ratio lower than ∼25) differ from the near-seafloor sediments in the study area, which have characteristics of Holocene sediments in the Sea of Japan, and suggest cementation of glacial sediments. Laminated sediments in some nodule samples are glacial sediments because laminations are records of a low sea level period in the semi-enclosed ocean. Similarity of diatom assemblages and contents in all carbonate samples is another evidence of glacial sediments in nodules. Glacial sediments with oceanic cold water species as low as Holocene sediments restricts the sediment age to before 20 cal. ky BP. Carbonate contents higher than 78 wt% suggest the cementation of poorly compacted sediments near the seafloor, and the date of carbonate cementation is, therefore, close to that of the cemented sediments. Most carbonate nodule samples in this study were formed in a glacial period and detection of 14C restricts this period to within ∼40 ky.  相似文献   
969.
970.
利用阿勒泰地区7个地面气象站1961—2011年51a的降水观测资料,运用线性趋势、变差分析、EOF、Molet小波变换、M—K突变检测、R/S分析法,分析了该地区近50a来冬季降水的时空变化特征。结果表明:近50a来,该地区冬季降水量存在自山区向河谷逐渐减少的分布特征,年际变化幅度由东北向西南逐渐减小;在空间分布上以全地区一致型为主,部分年份还呈现东北一西南差异分布。冬季降水量在196l一1968年处于偏多阶段,1968--1982年为偏少阶段,此后呈增多趋势。该地区降水以18a周期变化为主,20世纪70年代中后期出现8a的短周期,在90年代中期出现5a的短周期振荡。冬季降水量的突变特征并不显著。R/S分析表明该地区冬季降水量的增加趋势在未来仍将持续。  相似文献   
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