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1.
ADEOS-II satellite will be launched in the near future. It collocates many remote sensing instruments in the same platform. Among them, Global Image (GLI) is considered to be a main sensor which will play a key role. In order to understand the characteristics of future GLI ocean color images, a simulation and evaluation of the quality and availability of GLI typical ocean image has been done. In the paper, we first introduce the simulation models briefly, and simulate typical cases of radiance images at visible channels, in which the radiance distribution is based on geographic location, the satellite orbital parameters and sensor properties. A method, complex signal noise ratio (CSNR) to evaluate the image quality and availability, is developed according to the characteristics of image. Meanwhile, a series of CSNR images are generated from the simulated radiance components for different cases, which can be used to evaluate the quality and availability of GLI images before the ADEOS-II is placed in orbit. Finally, the quality and availability of GLI images are quantitatively analyzed by the simulated CSNR data. The results will be beneficial to the people who are in charge of GLI mission or plan to use the data from GLI.  相似文献   
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Intertidal seaweeds experience periodical desiccation and rehydration to different extents due to the tidal cycles and their vertical distributions. Their photosynthetic recovery process during the rehydration may show different patterns among the seaweeds from different zonations or depths at intertidal zone. In this study 12 species of seaweeds collected from the upper, middle, lower and sublittoral zones were examined. The relationship of the photosynthetic recovery to vertical distribution was assessed by comparing their patterns of photosynthetic and respiratory performances after rehydration following desiccation. Both the photosynthesis and dark respiration declined during emersion, showing certain degrees of recovery after re-immersion into seawater for most species, but the extents were markedly different from one species to the other. The species from upper intertidal zone after being rehydrated for 1 hour, following 2 hours of desiccation, achieved 100% recovery of their initial physiological activity, while most of the lower or sublittoral species did not achieve full recovery. It is the ability to withstand desiccation stress (fast recovery during rehydration), but not that to avoid desiccation (water retaining ability) that determines the distribution of intertidal seaweeds. Such physiological behavior during rehydration after desiccation reflects the adaptive strategy of intertidal seaweeds against desiccation and their capability of primary production in the process of rehydration.  相似文献   
4.
再生混凝土耐久性的试验研究系列探讨了再生混凝土抵抗冻融循环能力以及抵抗中性化能力方面做了基础性试验研究,表明了再生混凝土在水灰比相对较小的情况下,抵抗冻融循环能力较好,而抗碳化能力较差。这反映了再生混凝土在耐久性能方面还存在着很多疑难点,着眼于再生混凝土耐久性能的另一方面,即对再生混凝土抵抗干燥收缩能力方面做了基础性试验研究。试验以100%再生骨料替代天然碎石和砂粒制备再生混凝土试件,在恒温(20±2)℃,恒湿相对湿度(60±5)%的试验室内使混凝土试件自由干燥收缩180d。试验结果,再生混凝土试件与普通混凝土试件相比,干燥收缩率大,特别是早期干燥,几乎达到了普通混凝土试件的2倍以上。  相似文献   
5.
有效监测患病株方法的缺失是导致对松萎蔫病难以成功控制的主要原因之一。利用航空手段调查该病导致的针叶颜色变化已被证明是一种可靠的方法。为了克服该方法固有的缺点,笔者引用了近红外彩色胶片航拍方法。该项技术在获得正摄航拍图像时,通过图像处理可以增强松针颜色变化,获得较直接拍摄图像更明显的色差。因为图像可以在室内仔细处理,因此能解决飞行时间缺乏等问题。但是,该方法也存在对被压木无法获得其影像而漏检的缺陷。笔者研发的计算机软件可以将目标树标记在计算机图像文件上,并且标记树的地理位置数据和背景航拍图像并传输到装有内置GPS接收器的掌上电脑中,借助软件产生的图像导航定位系统,有利于地面接近标记树,从而可以现场检查和校正标记树的数据,并将修正数据传回至主机。此方法利用最新航拍图像技术建立对每株树处理和管理的连续资料,大大改善了防控松萎蔫病的措施。  相似文献   
6.
The brookite-phase TiO2 was prepared by a hydrothermal synthesis of titanium chloride solution.The thermolysis time and the pH value of the solution were controlled during the synthesis.X-ray diffraction experiments showed that TiO2 powders partially containing the brookite-phase were successfully obtained.A great amount of OH -in the reaction solution was found to be important to obtain the brookite phase because the intermediate complex leading to the brookite phase consumes more OH-than other phases like...  相似文献   
7.
基于深层特征抽取的日文词义消歧系统   总被引:1,自引:0,他引:1  
词义消歧的特征来源于上下文.日文兼有中英文的语言特性,特征抽取更为复杂.针对日文特点,在词义消歧逻辑模型基础上,利用最大熵模型优良的信息融合性能,采用深层特征抽取方法,引入语义、句法类特征用于消解歧义.同时,为避免偏斜指派,采用BeamSearch算法进行词义序列标注.实验结果表明,与仅使用表层词法类特征方法相比,本文构造的日文词义消歧系统的消歧精度提高2%~3%,动词消歧精度获得5%的改善.  相似文献   
8.
探讨再生骨料循环利用的可能性,对再生骨料制备的混凝土的各种性能,包括再生混凝土的力学以及耐久性能等方面做进一步的了解和深化。对再生混凝土的耐久性能之一,即再生混凝土抵抗中性化(碳化)能力,做了基础性试验研究。试验以100%再生骨料替代天然碎石和砂子制备再生混凝土试件,在二氧化碳浓度为(5±0.2)%的试验箱里促进中性化26周。试验结果,100%全再生混凝土与普通混凝土试件相比,抵抗中性化能力差,中性化几乎以3倍的速度增长。  相似文献   
9.
Rheumatoid arthritis is a common autoimmune disease characterized by chronic inflammation. We report a meta-analysis of genome-wide association studies (GWAS) in a Japanese population including 4,074 individuals with rheumatoid arthritis (cases) and 16,891 controls, followed by a replication in 5,277 rheumatoid arthritis cases and 21,684 controls. Our study identified nine loci newly associated with rheumatoid arthritis at a threshold of P < 5.0 × 10(-8), including B3GNT2, ANXA3, CSF2, CD83, NFKBIE, ARID5B, PDE2A-ARAP1, PLD4 and PTPN2. ANXA3 was also associated with susceptibility to systemic lupus erythematosus (P = 0.0040), and B3GNT2 and ARID5B were associated with Graves' disease (P = 3.5 × 10(-4) and 2.9 × 10(-4), respectively). We conducted a multi-ancestry comparative analysis with a previous meta-analysis in individuals of European descent (5,539 rheumatoid arthritis cases and 20,169 controls). This provided evidence of shared genetic risks of rheumatoid arthritis between the populations.  相似文献   
10.
有效监测患病株方法的缺失是导致对松萎蔫病难以成功控制的主要原因之一.利用航空手段调查该病导致的针叶颜色变化已被证明是一种可靠的方法.为了克服该方法固有的缺点,笔者引用了近红外彩色胶片航拍方法.该项技术在获得正摄航拍图像时,通过图像处理可以增强松针颜色变化,获得较直接拍摄图像更明显的色差.因为图像可以在室内仔细处理,因此能解决飞行时间缺乏等问题.但是,该方法也存在对被压木无法获得其影像而漏检的缺陷.笔者研发的计算机软件可以将目标树标记在计算机图像文件上,并且标记树的地理位置数据和背景航拍图像并传输到装有内置GPS接收器的掌上电脑中,借助软件产生的图像导航定位系统,有利于地面接近标记树,从而可以现场检查和校正标记树的数据,并将修正数据传回至主机.此方法利用最新航拍图像技术建立对每株树处理和管理的连续资料,大大改善了防控松萎蔫病的措施.  相似文献   
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