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251.
HY-1A is China's first ocean color satellite, and was launched on 15 May 2002as a piggyback satellite on the FY-1D satellite using the Long March rocket.There are two sensors on the satellite: China's Ocean Color and Temperature Scanner (COCTS), and the CCD Coastal Zone Imager (CZI). In the report,first, the properties and characteristics of HY-1A are briefly introduced; Second, the quality and availability of the data are evaluated by the mean of the Complex Signal Noise Ratio (CSNR) which is simulated theoretically; Third,the received HY-1A data are compared with SeaSTAR data to understand the accuracy of radiance measurement by the HY-1A; Finally, the remote sensing products of ocean color and temperature are mapped by HY-1A to study its application potentiality. The results show that the HY-1A has a latent capability for the application of marine environment detection, the management and protection of marine resources, and the furthering of national rights and interests.Meanwhile, some modifications are proposed for the next ocean satellite, suchas adding the case of tilt scanning, modification of the CCD element uniformity,and adding more ocean satellite receiving stations. 相似文献
252.
针对蜂群无人机快速充电排队问题,首次提出以平均队列长度和平均等待时间作为蜂群无人机充电排队优劣的评价指标。并通过理论分析和数值计算,在多充电平台的条件下,对蜂群无人机的分布式充电和集中式充电2种充电排队方式进行了比较和分析。得出蜂群无人机在泊松到达的条件下,随着服务强度的增加,评价指标对应的曲线出现了一个交叉点。在这个交叉点前,即服务强度较弱时,集中式充电排队方式优于分布式充电排队方式。在交叉点之后,即随着服务强度的增强,分布式充电排队方式将逐渐优于集中式充电排队方式。本文为蜂群无人机高效地完成任务提供了快速充电排队解决方案。 相似文献
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255.
嫦娥一号干涉成像光谱仪(IIM)获取的多波段图像数据对于月表矿物成分反演具有重要意义. 从目视质量、客观参数、几何配准精度、图像质量随时间的变化情况等方面对IIM 2C级的多波段图像数据质量进行了评价. 结果显示, 其两端波段范围的图像质量较差, 不能有效识别月表单元, 中间波段图像质量较好; 自然色图像显示IIM数据存在明显的横向色调不均一性. 利用图像的客观评价指标(辐射精度、清晰度、信息量)将干涉成像光谱仪图像数据与美国Clementine UV-VIS多光谱图像数据进行对比分析, 结果表明, IIM数据清晰度好于Clementine UV-VIS, 而在方差和信息量上弱于Clementine UV-VIS. 将IIM图像数据与Clementine多光谱数据统一到相同的空间分辨率, 进行配准精度评价, 其最大控制点配准误差为0.63pixel. 此外, 还对时间跨度两个月覆盖月表同一区域的IIM图像数据从辐射精度、信息量和清晰度方面进行了评价. 相似文献
256.
黄炜 《长沙航空职业技术学院学报》2013,13(2):37-41
针对教育信息基于互联网络的快速增长以及检索日趋复杂等问题,构建了基于领域本体的四层查询体系结构,采用5W1H分析法归纳了领域本体中的概念和关系,建立了基于5W1H的领域本体概念模型,重点研究了基于Jena的领域本体持久化技术和领域本体规则推理技术,设计了基于SPARQL查询规则和基于Jena推理规则的领域信息查询算法。以教师信息为例,采用Jena开发平台和MySQL数据库,实现了教师信息领域本体查询系统的精确查询、模糊查询和语义查询等功能。 相似文献
257.
Kozo Aoki 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The geometries, dipole moments, and rotational constants for the linear and/or bent cations, Cn+1H+ and CnN+(n = 1–6), were studied by the B3LYP method with the modest basis sets. For CnH+(n = odd; 3, 5, 7) and CnN+(n = even; 2, 4, 6), the theoretical rotational constants (Bes) of closed-shell singlet C3H+, C5H+, C7H+, CCN+, C4N+, and C6N+ were calculated to be about 11,244, 2420, 885.2, 11,970, 2439, and 880.8 MHz, respectively. By contrast, the triplets are stable than the corresponding singlets for CnH+(n = odd; 2, 4, 6) and CnN+(n = even; 3, 5) except CN+. 相似文献
258.
Yanjun An Suqin Wang Zongjie Hao Yiyong Zhou Yongding Liu 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
Based on the purpose of better exploring the function of green producers in the closed aquatic biological life support system, the condition of dynamic O2 evolution and performance of cyclic electron flow around photosystem I (CEF-PSI) in long-term ground batch culture of Euglena gracilis were studied, the relationship between linear electron flow (LEF) and CEF-PSI was revealed, the function of CEF-PSI was investigated. Excellent consistency in O2 evolution pattern was observed in cultures grown in both closed and open containers, O2 evolution was strictly suppressed in phase 1, but the rate of it increased significantly in phase 2. CEF-PSI was proposed to be active during the whole course of cultivation, even in the declining phase 3, it still operated at the extent of 47–55%. It is suggested that the relationship between LEF and CEF-PSI is not only competition but also reciprocity. CEF-PSI was proposed to contribute to the considerable growth in phase 1; it was also suggested to play an important protective role against photosystem II (PSII) photoinhibition at the greatly enhanced level (approximately 80–95%) on the 2nd day. Our results in this research suggest that E. gracilis had very particular photosynthetic characteristics, the strict O2 evolution suppression in the initial culture phase might be a special light acclimation behavior, and CEF-PSI could be an important mechanism involved in this kind of adaptation to the changeable light environment. 相似文献
259.
为了提升储备池的动态适应性能,克服回声状态网络(ESN)输出权值求解的病态不适定问题,平衡其拟合与泛化能力,提出了一种基于L1/2范数正则化的塑性回声状态网络故障诊断模型。在储备池构建中引入BCM规则对连接权矩阵进行预训练,并在目标函数中添加L1/2范数惩罚项以提高稀疏化效率,利用一个光滑化的L1/2正则子克服迭代数值振荡问题,并采用半阈值迭代法对模型进行求解。将模型应用于机载电台的故障诊断问题中,仿真结果证明了模型的有效性和优越性。 相似文献
260.
S.N. Kuznetsov L.L. Lazutin M.I. Panasyuk L.I. Starostin Yu.V. Gotseliuk N. Hasebe K. Sukurai M. Hareyama 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
It is a case study of a chain of three magnetic storms with a special attention to the particle dynamics based on CORONAS-F and SERVIS-1 low altitude satellite measurements. Solar proton penetration inside the polar cap and inner magnetosphere and dynamics at different phases of the magnetic storms was studied. We found, that solar protons were captured to the inner radiation belt at the recovery phase of the first and the second magnetic storms and additionally accelerated during the last one. No evidence of sudden commencement (SC) particle injection was found. Enhanced solar proton belt intensity with small pitch angles decreased slowly during satellite orbits for 30 days until the next magnetic storm. Then in 20–30 h we registered strong precipitation of these protons followed by the trapped proton flux dropout. Intensity decrease was more pronounced at lower altitudes and higher particle energies. 相似文献