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241.
我国某些球粒陨石及中铁陨石稀有气体的同位素丰度 总被引:2,自引:0,他引:2
本文测定了剑阁球粒陨石、岩庄球粒陨石、亳县球粒陨石及渭源中铁陨石和新近降落的东乌珠穆沁中铁陨石的稀有气体同位素丰度,根据He、Ne及Ar的测定结果计算宇宙射线暴露年龄,剑阁、岩庄及亳县球粒陨石的宇宙射线暴露年龄分别为5.8Ma、2.5Ma及38.0Ma,东乌珠穆沁及渭源中铁陨石分别为172Ma及17Ma. 相似文献
242.
微波复合调制信号校准系统是导弹制导专测设备的校准设备,主要用于确认导弹制导系统技术性能,使其能够满足规定的技术指标,保证其处于良好的技术状态。过去多采用人工手动操作、分散拆卸的校准方法,不仅耗时费力,校准的准确度也难以保证。目前模拟信号的解调普遍采用硬件实现,尝试将模拟信号采用一定的算法解调并根据解调的原基带信号测量相关参数,实现解调测量软件化。 相似文献
243.
针对卫星载荷间基于控制器局域网(CAN)总线的IP通信,提出了一种CAN接口虚拟化机制,称为IPoverCAN。通过IP地址和CAN地址映射、IP报文分片/重组和多路缓冲队列管理等机制,将CAN接口抽象为虚拟的标准以太网接口。试验结果表明,IPoverCAN机制实现了CAN数据帧和IP报文之间的实时高效转换,可用于卫星载荷间通信等对设备质量和体积敏感的领域。 相似文献
244.
Sebastián Sánchez Manuel PrietoÓscar R. Polo Pablo ParraAntonio da Silva Óscar GutiérrezRonald Castillo Javier FernándezJavier Rodríguez-Pacheco 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
ESA’s medium-class Solar Orbiter mission is conceived to perform a close-up study of our Sun and its inner heliosphere to better understand the behaviour of our star. The mission will provide the clues to discover how the Sun creates and controls the solar wind and thereby affects the environments of all the planets. The spacecraft is equipped with a comprehensive suite of instruments. The Energetic Particle Detector (EPD) is one of the in-situ instruments on-board Solar Orbiter. EPD is composed of five different sensors, all of them sharing the Instrument Control Unit or ICU that is the sole interface with the spacecraft. This paper emphasises on how the hardware/software co-design approach can lead to a decrease in software complexity and highlights the versatility of the toolset that supports the development process. Following a model-driven engineering approach, these tools are capable of generating the high-level code of the software application, as well as of facilitating its configuration control and its deployment on the hardware platforms used in the different stages of the development process. Moreover, the use of the Leon2ViP virtual platform, with fault injection capabilities, allows an early software-before-hardware verification and validation and also a hardware–software co-simulation. The adopted solutions reduce development time without compromising the whole process reliability that is essential to the EPD success. 相似文献
245.
本文介绍了基于虚拟仪器技术开发的阳极化电压控制器校准装置,对系统软件和硬件进行了分析,利用该校准装置能够实现对阳极化电压控制器的校准,满足飞机铝合金零部件阳极化表面处理的工艺规范要求。 相似文献
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In order to provide accurate launching pitching angular velocity(LPAV) for the exterior trajectory optimization design, multi-flexible body dynamics(MFBD) technology is presented to study the changing law of LPAV of the rotating missile based on spiral guideway. An MFBD virtual prototype model of the rotating missile launching system is built using multi-body dynamics modeling technology based on the built flexible body models of key components and the special force model.The built model is verified with the frequency spectrum analysis. With the flexible body contact theory and nonlinear theory of MFBD technology, the research is conducted on the influence of a series of factors on LPAV, such as launching angle change, clearance between launching canister and missile,thrust change, thrust eccentricity and mass eccentricity, etc. Through this research, some useful values of the key design parameters which are difficult to be measured in physical tests are obtained. Finally,a simplified mathematical model of the changing law of LPAV is presented through fitting virtual test results using the linear regression method and verified by physical flight tests. The research results have important significance for the exterior trajectory optimization design. 相似文献
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针对卫星拍摄的以深空为背景的视频图像中空间运动目标的检测问题进行了研究,提出了一种基于运动信息的目标检测算法。首先,通过均值滤波对图像进行降噪处理;然后,采用基于局部统计的可变阈值来分割单帧图像,使用灰度重心法计算像点坐标。当卫星凝视目标区域时,恒星可以认为是静止的,而目标依旧在运动,基于此,可检测出空间运动目标。基于某型卫星在轨拍摄的视频图像验证了算法的有效性。 相似文献