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虚拟化技术在资源分配、应用移植和隔离等方面有着巨大优势,为了满足航空计算领域对综合化、智能化的需求,以及机载嵌入式系统对实时性、功耗和体积等方面的制约,开展虚拟化技术在航空计算领域的应用研究。首先介绍虚拟化技术的基本原理,对比虚拟机和容器的主要特点;其次分析虚拟化技术应用的三个例子,虚拟化操作系统在多核处理器上的应用、混合容器计算架构和DevOps软件持续交付过程;最后提出两种应用构想,机载软件DevOps综合开发环境和多核高性能计算单元,对虚拟化技术在航空计算领域的应用提出技术思路,并给出基础设计架构。结果表明:虚拟化技术应用于航空计算领域能够提高航空电子系统的模块化和综合化水平,基础设计架构能够充分利用机载计算资源、提高计算效率。 相似文献
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存储整合的目标是采用先进、成熟的技术和产品,针对企业当前已存在的不同类型的存储资源,解决异构存储系统在兼容性、扩展性、可靠性等方面的问题。本文对当前存储整合技术进行梳理并结合不同企业实际情况提出了企业存储系统整合规划意见。 相似文献
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Mark Nelson W.F. DempsterJ.P. Allen 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
To achieve sustainable, healthy closed ecological systems requires solutions to challenges of closing the water cycle – recycling wastewater/irrigation water/soil medium leachate and evaporated water and supplying water of required quality as needed for different needs within the facility. Engineering Biosphere 2, the first multi-biome closed ecological system within a total airtight footprint of 12,700 m2 with a combined volume of 200,000 m3 with a total water capacity of some 6 × 106 L of water was especially challenging because it included human inhabitants, their agricultural and technical systems, as well as five analogue ecosystems ranging from rainforest to desert, freshwater ecologies to saltwater systems like mangrove and mini-ocean coral reef ecosystems. By contrast, the Laboratory Biosphere – a small (40 m3 volume) soil-based plant growth facility with a footprint of 15 m2 – is a very simplified system, but with similar challenges re salinity management and provision of water quality suitable for plant growth. In Biosphere 2, water needs included supplying potable water for people and domestic animals, irrigation water for a wide variety of food crops, and recycling and recovering soil nutrients from wastewater. In the wilderness biomes, providing adequately low salinity freshwater terrestrial ecosystems and maintaining appropriate salinity and pH in aquatic/marine ecosystems were challenges. The largest reservoirs in Biosphere 2 were the ocean/marsh with some 4 × 106 L, soil with 1 to 2 × 106 l, primary storage tank with 0 to 8 × 105 L and storage tanks for condensate and soil leachate collection and mixing tanks with a capacity of 1.6 × 105 L to supply irrigation for farm and wilderness ecosystems. Other reservoirs were far smaller – humidity in the atmosphere (2 × 103 L), streams in the rainforest and savannah, and seasonal pools in the desert were orders of magnitude smaller (8 × 104 L). Key technologies included condensation from humidity in the air handlers and from the glass space frame to produce high quality freshwater, wastewater treatment with constructed wetlands and desalination through reverse osmosis and flash evaporation were key to recycling water with appropriate quality throughout the Biosphere 2 facility. Wastewater from all human uses and the domestic animals in Biosphere 2 was treated and recycled through a series of constructed wetlands, which had hydraulic loading of 0.9–1.1 m3 day−1 (240–290 gal d−1). Plant production in the wetland treatment system produced 1210 kg dry weight of emergent and floating aquatic plant wetland which was used as fodder for the domestic animals while remaining nutrients/water was reused as part of the agricultural irrigation supply. There were pools of water with recycling times of days to weeks and others with far longer cycling times within Biosphere 2. By contrast, the Laboratory Biosphere with a total water reservoir of less than 500 L has far quicker cycling rapidity: for example, atmospheric residence time for water vapor was 5–20 min in the Laboratory Biosphere vs. 1–4 h in Biosphere 2, as compared with 9 days in the Earth’s biosphere. Just as in Biosphere 2, humidity in the Laboratory Biosphere amounts to a very small reservoir of water. The amount of water passing through the air in the course of a 12-h operational day is two orders of magnitude greater than the amount stored in the air. Thus, evaporation and condensation collection are vital parts of the recycle system just as in Biosphere 2. The water cycle and sustainable water recycling in closed ecological systems presents problems requiring further research – such as how to control buildup of salinity in materially closed ecosystems and effective ways to retain nutrients in optimal quantity and useable form for plant growth. These issues are common to all closed ecological systems of whatever size, including planet Earth’s biosphere and are relevant to a global environment facing increasing water shortages while maintaining water quality for human and ecosystem health. Modular biospheres offer a test bed where technical methods of resolving these problems can be tested for feasibility. 相似文献
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V-22“鱼鹰”倾转旋翼机研制历程与关键技术 总被引:1,自引:0,他引:1
倾转旋翼机具有速度快、噪声小、航程远、载重大和耗油率低等优点,本文介绍了贝尔直升机公司V-22"鱼鹰"倾转旋翼机从原理验证阶段的XV-3机到方案验证阶段的XV-15机,再到实用工程研制阶段的V-22"鱼鹰"机循序渐进的研制历程,并叙述了倾转旋翼机研制中的几项关键技术。 相似文献
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在分析航天制造技术的重要作用及特征的基础上,总结了我国航天制造技术发展取得的成绩,剖析了现存在的主要问题,结合我国航天事业发展的需要,提出了发展航天制造技术需要重点采取的对策。 相似文献
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总结了国内外变循环涡扇冲压组合发动机的发展现状,对比分析了有/无能量传递构型的变循环涡扇冲压组合发动机的工作原理及优缺点。提炼了变循环涡扇冲压组合发动机的关键技术,包括总体性能仿真技术、高速宽工况风扇设计技术、加力/冲压燃烧室设计技术、热管理系统设计技术以及模态转换设计技术。基于国内需求和相关技术研究现状,给出了变循环涡扇冲压组合发动机后续重点研究方向的建议,包括发动机总体性能设计与仿真工具、发动机多设计点多学科耦合设计方法、发动机热管理系统设计与仿真建模以及关键部件的设计与试验。 相似文献