2012–2014 China's Earth Observation and Earth Science Development

Human beings are now facing global and regional sustainable development challenges.In China, Earth observation data play a fundamental role in Earth system science research. The support given by Earth observation data is required by many studies, including those on Earth's limited natural resources, the rapid development of economic and social needs, global change, extreme events, food security, water resources, sustainable economic and urban development, and emergency response. Application operation systems in many ministries and departments in China have entered a stage of sustainable development, and the State Key Project of High-Resolution Earth Observation Systems has been progressing since 2006. Earth observation technology in China has entered a period of rapid development.     

基于BDI模型的Agent在航班时隙分配问题研究

随着民航运输的快速发展,时隙资源日益紧缺,为了保证航班的正常飞机,提出了基于BDI(Beliefs-Desires-Intentions)Agent分布式时隙优化模型,并对厦门机场某一时间段内的时隙分配进行验证,结果表明,模型可以大大减少航班的延误损失,具有较强的实际应用性。     

基于加权全变差最小化的中子外部CT重建算法

针对中子外部CT检测需求，提出了基于加权方向全变差（WDTV）最小化的中子外部CT重建算法。首先，利用平行束数据对称性原理将正弦图中旋转中心另一侧缺失的投影数据进行补充；其次，采用传统FBP算法进行了外部CT扫描模式下的CT重建。为了抑制传统FBP、SART算法重建图像中径向边缘伪影，采用WDTV算法计算沿径向和周向方向的局部方向差分并作加权和。另外，在重建模型的WDTV项中引入2个权重参数以控制径向边缘和切向边缘的不同响应强度。最后，采用所提算法研究了重建图像质量与投影数据量的关系。计算机仿真和真实冷中子实验表明:基于WDTV最小化的中子外部CT重建算法能够有效抑制径向边缘伪影，获得高质量重建图像。      

Fringe fitting and group delay determination for geodetic VLBI observations of DOR tones

Extracting the group and phase delays of interferometric observations produced in the Very Long Baseline Interferometry (VLBI) measurement concept requires a special fringe fitting and delay search algorithm for the recorded bandwidth. While fringe fitting is in use routinely for several megahertz wide channels in geodetic and astrometric VLBI with quasar observations, fringe fitting for artificial tones of very small bandwidth of artificial signals for Differential One-way Ranging (DOR) requires a different way of handling. In a project called Observing the Chang’E-3 Lander with VLBI (OCEL), the DOR tones emitted by the Chang’E-3 lander were observed in a standard geodetic VLBI mode with 8 or 4?MHz wide channels to maintain compatibility with the corresponding quasar observations. For these observations, we modified the existing fringe fitting program of the Haystack Observatory Processing Software (HOPS), fourfit, to properly handle narrow band DOR tones. The main motivations are that through this modification, the data of quasars and artificial radio sources can be processed in the existing geodetic analysis pipeline, and that the algorithm can be used for similar projects as well. In this paper, we describe the algorithm and show that the new algorithm produces much more reliable group delay results than using the standard fourfit algorithm. This is done by a simulation test and in particular by processing of real observations. It is shown that in many cases, systematic deviations of several nanoseconds, which are seen with the standard fourfit algorithm, can be avoided. The ultimate benefit of the new procedure is demonstrated by reducing the errors in delay triangle closures by at least a factor of 3, which, in the OCEL case, is from ～300 to ～100?ps.     

基于乙炔基封端酰亚胺和氰酸酯树脂的互穿网络聚合物

以2，3，3'，4'-联苯四甲酸二酐和2，2'-双三氟甲基-4，4'-联苯二胺为单体、4-乙炔基邻苯二甲酸酐为封端剂合成了不同聚合度的聚酰亚胺低聚物（BETI），将其溶于双氛A型氰酸酯单体制备了改性氰酸酯树脂，对改性氰酸酯树脂的固化行为进行了详细探究，并对其固化物的热学性能、力学性能和介电性能等进行了表征与分析。结果表明:BETI对氰酸酯树脂的聚合有明显的催化作用，可以降低固化温度，缩短凝胶时间。基于BETI和氰酸酯树脂的互穿网络聚合物（IPN）的热性能和力学性能与纯氰酸酯树脂相比都有一定的提高。当加入质量分数30%、聚合度为19的BETI树脂时，固化物的玻璃化转变温度从297 ℃提高到309 ℃，热失重5%时温度从425 ℃提高到了431 ℃；拉伸强度从76 MPa提高到了94 MPa，冲击强度从24 kJ/m2℃提高到了31 kJ/m2。加入BETI后，聚合物的介电常数稍稍高于纯氰酸酯树脂。由于具有良好工艺性和材料性能，BETI改性氰酸酯树脂可作为基体树脂应用于航空航天等领域。      

热解气体燃烧对炭化复合材料烧蚀热响应影响规律

在近空间高超声速飞行器飞行时间长、马赫数不断增加的发展趋势下，热防护与轻量化的矛盾越来越突出。基于此，开展了热解气体燃烧对炭化复合材料表面烧蚀影响的相关数值模拟研究，并与风洞试验结果进行了对比。结果表明：热解气体的燃烧可降低炭化复合材料表面的烧蚀厚度，并且随着气动热的增加，热解气体燃烧对材料表面碳的保护作用越来越明显。研究成果可为下一代近空间高超声速飞行器热防护系统的优化设计提供技术支撑。     

含天然与人工内部缺陷轮盘裂纹扩展特性对比分析

为达到应用人工内部缺陷获得轮盘裂纹扩展特性，开展了含天然与人工内部缺陷轮盘高速旋转低周疲劳裂纹扩展对比试验，并通过无损检测分析、断口分析研究了裂纹扩展特性的差异，提出了含人工缺陷轮盘损伤容限分析思路。无损检测更易识别人工内部缺陷的特征及其变化；人工缺陷区呈碎裂状，有大量的晶间断裂，与天然缺陷区有明显差异；非缺陷区两者无明显差异。天然与人工缺陷区的裂纹扩展速率分别为0.2-0.4μm/次、0.6-1.2μm/次，均远大于基体材料理论值；1#盘加载突变区外断口反推寿命与第二加载阶段循环数的最大误差是12%；2#盘缺陷区外断口反推寿命占总循环数的44.9%-51.9%。基于人工缺陷区定义初始裂纹，排除人工与天然缺陷差异的影响，可获得轮盘裂纹扩展特性。