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951.
GIS是国土资源信息系统及办公自动化系统的基石 ,亦将是国土资源工作的各个领域中最具影响力、应用最广泛的一种技术。本文在分析已有矿产资源含量数据库特点和GIS应用现状的基础上 ,提出了在GIS平台上建立浙江省矿产资源储量管理信息系统的初步设想 ,概要论述了系统的功能、软件流程和系统结构  相似文献   
952.
Phytoplankton pigment patterns and community composition were investigated in the northern South China Sea using high-performance liquid chromatography and the CHEMTAX software from February 11 to 23, 2009. We recognized four different vertical distribution patterns of pigments: chlorophyll a (Chl a)-like type, divinyl chlorophyll a (DV Chl a) type, even distribution type, and surface type. The average value of ratios of accessory photo-protective pigments (APP) to accessory photo-synthetic pigments was 0.89±0.63 in the upper 50 m and 0.16±0.06 below 50 m depth. With increasing depth, APP decreased and photo-synthetically active radiation was attenuated. There was an obvious succession in the phytoplankton community from inshore to the open sea. Diatoms were dominant in the inshore region, while pelagophytes, Prochlorococcus, cyanobacteria and prymnesiophytes were dominant in the open sea. The vertical distribution of phytoplankton also differed greatly from inshore to the open sea. In the coastal and shelf region, diatoms were important components in the whole water column. Cyanobacteria also had a high abundance at the Subsurface Chlorophyll a Maxima (SCM) in the shelf region. In the slope and open sea, Prochlorococcus and cyanobacteria were important groups above the SCM, while pelagophytes dominated below the SCM.  相似文献   
953.
介绍了一种新颖的静态传感器网络实现方法,它利用可移动的中继节点来收集静态传感器网络的数据,有效的节约各传感器节点的能源,延长整个传感器网络的有效工作时间。也可以对该方法进行适当的改进,应用到某些实时性要求较高的场合中去。然后介绍了应用该原理实现的一个通讯协议。  相似文献   
954.
Most evaluation of the consistency of multisensor images have focused on Normalized Difference Vegetation Index (NDVI) products for natural landscapes, often neglecting less vegetated urban landscapes. This gap has been filled through quantifying and evaluating spatial heterogeneity of urban and natural landscapes from QuickBird, Satellite pour l'observation de la Terre (SPOT), Ad- vanced Spacebome Thermal Emission and Reflection Radiometer (ASTER) and Landsat Thematic Mapper (TM) images with variogram analysis. Instead of a logarithmic relationship with pixel size observed in the corresponding aggregated images, the spatial variability decayed and the spatial structures decomposed more slowly and complexly with spatial resolution for real multisensor im- ages. As the spatial resolution increased, the proportion of spatial variability of the smaller spatial structure decreased quickly and only a larger spatial structure was observed at very coarse scales. Compared with visible band, greater spatial variability was observed in near infrared band for both densely and less densely vegetated landscapes. The influence of image size on spatial heterogeneity was highly dependent on whether the empirical sernivariogram reached its sill within the original image size. When the empirical semivariogram did not reach its sill at the original observation scale, spatial variability and mean characteristic length scale would increase with image size; otherwise they might decrease. This study could provide new insights into the knowledge of spatial heterogeneity in real multisen- sor images with consideration of their nominal spatial resolution, image size and spectral bands.  相似文献   
955.
利用2009-01—2013-05月发生在赣西北地区的233次M L≥1.0地震数字波形资料,采用尾波归一化方法计算了阳新台、九江台、修水台、高安台、宜春台的P波S波的衰减,结果显示,除修水台最佳流逝时间约为60 s外,其他四个台站的最佳流逝时间为30 s左右;九江-瑞昌震区内平均P波和S波的Q值分别为:Q P(f)=(15.97±1.87)f(1.66±0.06)和Q S(f)=(25.27±1.90)f(1.15±0.04)。  相似文献   
956.
A pyrethroid insecticide-degrading bacterium, strain HS-24, was isolated from an offshore seawater environment. The strain, which can degrade cypermethrin(CYP) and deltamethrin(DEL), was identified as Methylophaga sp. The optimal culture and degradation conditions for CYP and DEL by strain HS-24 is pH 7 at 28°C. Under optimum culture conditions, strain HS-24 exhibited a broad degradation concentration range of 100, 200, 400, 600, and 800 mg/L for CYP and DEL. The metabolic intermediates were analyzed by NMR, which provided strong evidence that CYP and DEL removal occurred mainly because of a biological process. The toxicity of the degradation products of strain HS-24 was studied simultaneously by measuring the light output of the luminescence bacterium. This demonstrated that the biodegradation ability of strain HS-24 significantly decreased the toxicity of CYP- and DEL-contaminated aquaculture seawater. Finally, the findings of this paper indicate that strain HS-24 is thus revealed as a biological agent for the remediation of marine aquatic environments.  相似文献   
957.
??LAMBDA????????GNSS????????????????????????????????????????????????????????????????????????Ratio??????????????????Ratio?????????????????????L1??L2?????λ????????????????????÷?????????????????????????????????????????????????????????  相似文献   
958.
?????????????????????????1997??11??8?????????????o????Ч?????????????????????????λ?????????Ч????????仯??????????????????????Ч?????????仯????????λ?????????????????????????Ч????????仯??????????λ????????????????????  相似文献   
959.
????IGS???????GIM???????????????TEC??Total Electron Content?????????2007-2011???????й??????????17???M??≥6.0????????????????????PCA??Principal Component Analysis?? ???????????TEC??????????????????????????б???????????PCA??????????????????????????????????????????£???????????????TEC????????????????????????????0~5??  相似文献   
960.
陈刘组为新建立的岩石地层单位,代表广西早三叠世盆地滨岸相带沉积类型。层型剖面位于贵港市陈刘村附近。层型定义指位于龙潭组与板纳组之间的沉积序列,岩性为灰绿、紫红色泥岩、粉砂细砂岩夹少量火山岩及碳酸盐岩,含菊石、双壳类、牙形石等化石,厚359m。  相似文献   
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