无人机指控平台信息接入系统的发展研究

介绍了无人机指控平台信息接入系统的概念和功能，从无人机指控平台架构的发展历程入手，总 结不同无人机指控平台架构时期信息接入系统的历史形态，然后结合前沿高新技术的发展以及其在无人机指控 平台的应用，对无人机指控系统信息接入系统各阶段的使用形态进行展望预测并分析，对未来无人机指控平台 的信息接入系统设计有一定的指导意义。     

Possible nutrient limiting factor in long term operation of closed aquatic ecosystem

To investigate nutrient limitation effect on the community metabolism of closed aquatic ecosystem and possible nutrient limiting factors in the experimental food chains, depletion of inorganic chemicals including carbon, nitrogen and phosphorous was tested. A closed aquatic ecosystem lab module consisting of Chlorella pyrenoidosa and Chlamydomonas reinhardtii, Daphnia magna and associated unidentified microbes was established. Closed ecological systems receive no carbon dioxide; therefore, we presumed carbon as a first limiting factor. The results showed that the algae population in the nutrient saturated group was statistically higher than that in the nutrient limited groups, and that the chlorophyll a content of algae in the phosphorus limited group was the highest among the limited groups. However, the nitrogen limited group supported the most Daphnia, followed by the carbon limited group, the nutrient saturated group and the phosphorus limited group. Redundancy analysis showed that the total phosphorus contents were correlated significantly with the population of algae, and that the amount of soluble carbohydrate as feedback of nutrient depletion was correlated with the number of Daphnia. Thus, these findings suggest that phosphorus is the limiting factor in the operation of closed aquatic ecosystem. The results presented herein have important indications for the future construction of long term closed ecological system.     

基于效能的先进战斗机航电系统动态重构方法

为满足未来先进战斗机全战斗过程的对敌压制能力需求，分析了作战任务与航电系统支持能力间的关系，建立了"作战任务-航电能力-资源需求"间的关系矩阵和航电系统效能模型；以最大化全飞行阶段航电功能整体效能和飞行安全为目标设计了针对不同作战场景的航电系统动态重构策略及重构流程；通过数值分析，对比了动态重构航电系统与静态配置航电系统在不同作战区边界的效能，表明动态重构特性能有效提高战斗机各阶段的作战效能，提高有限资源条件下的阶段优势。     

11.4μm外腔宽调谐量子级联激光器研究

光谱法是目前最主要的痕量气体检测手段之一。外腔量子级联激光器因其宽调谐、窄线宽、中红外波段输出等特点成为痕量检测系统中的重要激光光源。针对有毒有害大气污染物检测需求,采用新型Littrow外腔技术,实现中心波长11.4μm中红外波段827.7cm?1～928.7cm?1(波长10.7μm～12.08μm)宽调谐激光输出,线宽小于1cm?1。该波段的宽调谐激光输出是国内首次报道,解决了三氯乙烯、光气、萘等痕量有毒有害气体同时在线检测的难题。     

冗余飞轮姿控系统控制分配与重构研究

针对具有多冗余执行机构的航天器姿态控制系统,给出了处理冗余的控制分配方案,该方案考虑了幅值和速度约束条件并实现了二次最优．仿真验证了分配环节的有效性,并比较了不同求解算法下的动态分配效果．针对执行机构可能出现的故障,提出了结合故障诊断与隔离系统的执行环节控制重构方法,实现了机构故障下的容错控制,通过卫星姿态跟踪控制仿真,验证了分配和重构环节与控制回路的相容性．     

卫星编队队形重构中的模型选择

推导了卫星编队进行燃料最优队形重构时,两组Lawden方程（时间域和真近点角域）下所建立目标函数的数学关系,指出在不需要解析解的情况下,动力学模型应选择时间域下的Lawden方程,目标函数应建立在时间域。首先,分别针对脉冲推力和持续推力机动,研究了两组方程下目标函数的差异。然后,以持续推力式重构方法为例,构造了燃料最优目标函数,基于最大值原理,建立了队形重构的两点边值问题。然后,采用边界迭代法求解初始协态变量,确定最优的控制加速度。最后通过数学仿真验证了模型分析的正确性及算法的有效性。
     

航天器入轨段测轨数据误差特性及定轨结果分析

分析了航天器发射任务入轨段各类测轨数据的误差特性及入轨段各类测轨数据的常用定轨方法的定轨精度,提出了解决定轨结果一致性差、优选困难的方法,并用仿真计算结果和实战任务数据计算结果予以验证.     

Raman spectroscopic analysis of a desert cyanobacterium Nostoc sp. in response to UVB radiation

Cyanobacteria are capable of tolerating environmental extremes. To survive in extreme environments, cyanobacteria have developed the capability to adapt to a variety of stresses. For example, cyanobacteria have adopted a number of strategies with which to survive UV stress, including expression of UV-screening pigments and antioxidant systems. We have previously shown that several antioxidants are significantly expressed in Nostoc sp. by UVB irradiation. We report here that the content of UV-responsive biomarkers such as β-carotene and scytonemin can be easily detected by Fourier transform Raman spectroscopy with use of a small sample size and that the content of β-carotene is dependant on the UVB intensity and exposure time. Our results indicate that Raman spectroscopy may be a helpful tool to analyze UV-protective molecules of cyanobacterium in astrobiological studies without access to large sample sizes and complicated extractions, which are needed by other analytical techniques such as high-performance liquid chromatography and mass spectrometry.     

Chirp超宽带数字接收机设计与实现

文章针对超宽带通信技术快速发展的需要,设计了一个Chirp超宽带数字接收机。该接收机使用数字匹配滤波器避免了模拟滤波器带来的巨大插入损耗,并可以使用较为简单的方法实现时间同步。在硬件实现上,利用单比特量化匹配滤波器系数降低接收机的资源占用。实验表明该接收机结构简单、资源占用少、性能较好。     

连续短线段空间圆弧转接与插补

针对连续短线段高速加工控制需求,研究了利用空间圆弧转接实现高速插补的方法。建立了圆弧转接数学模型,研究了转接的几何约束和运动约束、转接参数计算、空间圆弧插补等相关理论与算法,并详细分析了算法的使用范围、效率制约因素和计算量等工程实现相关问题。仿真和加工实验表明:该转接算法能显著提高加工效率,减小振动,改善工件表面质量。作为空间圆弧转接算法基础的空间圆弧插补算法对空间任意平面内圆弧插补具有实用价值。本文所有算法已经在自主研发的数控平台上进行了验证,应用效果良好。