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21.
In the context of space missions, where science is the most important goal, careful planning and detailed commanding are fundamental. The planning and commanding phases are activities whose complexity depends on the instrument characteristics, environmental constraints and scientific goals. The purpose of this work is to describe in detail these activities for the Jovian Infrared Auroral Mapper (JIRAM) on board the Juno spacecraft, a NASA mission to Jupiter.To maximize the scientific return, we fully employ the flexibility offered by the JIRAM operational modes to efficiently plan observations of various Jovian targets, in spite of the harsh Jovian radiation environment and the spinning state of the Juno spacecraft. Moreover, the JIRAM observations are limited by the challenging pointing and timing scheme of the mission, which impose constraints on both the observation planning and instrumental commanding.  相似文献   
22.
针对资源环境与城乡规划管理专业的特点,通过对G IS课程特点的分析,对该专业的G IS课程的教学方法和教学手段进行了探讨,对面向资源环境与城乡规划管理专业如何进行地理信息系统课程教学改革提出了几点建议。  相似文献   
23.
概要介绍了中国移动卫星通信市场的基本需求;提出了建立中国移动通信卫星系统的一些基本设计考虑,包括系统的设计目标及任务、通信体制的选择、轨道的选择、频段的选择等;并摘要介绍了中国及亚太地区区域性移动通信卫星方案的基本性能参数,如卫星EIRP,SFD,G/T值等,并证明了利用静止轨道通信卫星进行手持机通信的可行性。  相似文献   
24.
基于智能Agent的卫星计划系统协作中间件研究   总被引:1,自引:0,他引:1  
Agent技术是分布式系统领域未来发展的重要方向之一,计划协同系统是航天项目在现有基础条件下提高运作效率的关键所在。本文通过研究国内外的计划系统,提出了基于智能Agent技术的计划协同架构中间件CPSOM方案,并且给出一种实现途径。  相似文献   
25.
This paper is one of the components of a larger framework of activities whose purpose is to improve the performance and productivity of space mission systems, i.e. to increase both what can be achieved and the cost effectiveness of this achievement. Some of these activities introduced the concept of Functional Architecture Module (FAM); FAMs are basic blocks used to build the functional architecture of Plan Management Systems (PMS). They also highlighted the need to involve Science Operations Planning Expertise (SOPE) during the Mission Design Phase (MDP) in order to design and implement efficiently operation planning systems. We define SOPE as the expertise held by people who have both theoretical and practical experience in operations planning, in general, and in space science operations planning in particular. Using ESA’s methodology for studying and selecting science missions we also define the MDP as the combination of the Mission Assessment and Mission Definition Phases. However, there is no generic procedure on how to use FAMs efficiently and systematically, for each new mission, in order to analyse the cost and feasibility of new missions as well as to optimise the functional design of new PMS; the purpose of such a procedure is to build more rapidly and cheaply such PMS as well as to make the latter more reliable and cheaper to run. This is why the purpose of this paper is to provide an embryo of such a generic procedure and to show that the latter needs to be applied by people with SOPE during the MDP. The procedure described here proposes some initial guidelines to identify both the various possible high level functional scenarii, for a given set of possible requirements, and the information that needs to be associated with each scenario. It also introduces the concept of catalogue of generic functional scenarii of PMS for space science missions. The information associated with each catalogued scenarii will have been identified by the above procedure and will be relevant only for some specific mission requirements. In other words, each mission that shares the same type of requirements that lead to a list of specific catalogued scenarii can use this latter list of scenarii (regardless of whether the mission is a plasma, planetary, astronomy, etc. mission). The main advantages of such a catalogue are that it speeds-up the execution of the procedure and makes the latter more reliable. Ultimately, the information associated to each relevant scenario (from the catalogue or freshly generated by the procedure) will then be used by mission designers to make informed decisions, including the modification of the mission requirements, for any missions. In addition, to illustrate the use of such a procedure, the latter is applied to a case study, i.e. the Cross-Scale mission. One of the outcomes of this study is an initial set of generic functional scenarii. Finally, although border line with the above purpose of this paper, we also discuss multi-spacecraft specific issues and issues related to the on-board execution of the plan update system (PUS). In particular, we show that the operation planning cost of N spacecraft is not equal to N times the cost of 1 spacecraft and that on-board non-synchronised operation will not require inter-spacecraft communication. We also believe that on-board PUS should be made possible for all missions as a standard.  相似文献   
26.
航空兵任务规划系统中飞机空对地攻击航线解算的准确性、航线生成质量和航线解算速度是衡量任务规划系统能力的重要指标。飞机空对地攻击航线设计是飞机航线规划中典型的多约束复杂机动,其在设计与使用过程中受到来自时间、空间及飞机本体的多维约束,对飞行动力学建模与航迹优化提出了较高的要求。本文利用面向对象的思想对飞机无侧滑动力学模型...  相似文献   
27.
民用飞机飞行试验任务优化技术研究与实现   总被引:1,自引:1,他引:0       下载免费PDF全文
针对具有复杂耦合关系的试飞任务难以进行全局优化的问题,提出了一种计算机辅助任务优化方法,该方法将复杂的试飞任务优化问题分解为多项串联问题,然后采用启发式算法(A*算法)和遗传算法相结合的混合遗传算法获得试飞任务单的较优组合,并以此为基础实现对试飞任务进行全局优化。工程应用表明,通过使用该方法获得的试飞任务优化结果置信度高,可有效缩短飞行试验任务周期和降低试验成本。  相似文献   
28.
民用飞机试飞规划与管理技术研究   总被引:1,自引:1,他引:0       下载免费PDF全文
梳理了通用的民机试飞需求类型,讨论了民机试飞任务分工和试飞计划制订原则,分析了民机试飞科目特点和逻辑关系,研究并提出了一种民机试飞任务优化方法,系统地阐述了试飞规划与管理体系,实现了民机试飞的闭环控制,解决了国内试飞规划中未能系统研究的问题,并创建了一套具有国际先进水平的民机试飞规划与管理系统(Flight Test Control System,简称"FTCS")。FTCS已在实际型号试飞工作中得到了验证和应用,起到了减少试飞架次和提高试飞效率的作用,具有实际的工程应用意义。  相似文献   
29.
企业投入产出方法与制造资源计划方法的结合研究   总被引:4,自引:0,他引:4  
提出以企业基础信息平台为基础数据,在企业工序产品生产计划、外购品采购计划、成本计划、物料清单、成本核算等方面,实现企业投入产出方法与制造资源计划方法的结合。  相似文献   
30.
ERP的发展现状及未来趋势   总被引:1,自引:0,他引:1  
ERP(Enterprlse Resources Planning企业资源计划)是指建立在信息技术的基础上,以系统化的管理思想,为企业决策层及员工提供决策运行手段的管理平台。ERP系统集信息技术与先进的管理思想于一身,成为现代企业的运行模式,反映时代对企业合理调配资源、最大化地创造社会财富的要求,成为企业在信息时代生存、发展的基石。对ERP发展现状及其未来可能的发展趋势的研究,可为企业顺利实施ERP提供依据。  相似文献   
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