直升机航空电子综合仿真系统研究

综合仿真系统是直升机航空电子系统研制过程中必不可少的支持设施，本文简要介绍了其基本原理、系统结构和主要软件模块。     

综合火力/飞行控制系统火飞耦合器设计技术研究

为提高武器的攻击精度、延长可攻击时间，本文建议了IFFC系统中的空-空射击作战模态，研究了火飞耦合器的基本结构及其参数优化设计方法，提出了一种以随机射线优化方法和IFFC系统数字仿真相结合的离线寻优的参数设计策略。在寻找过程中采用了以减小脱靶量为优化准则的目标函数。数字仿真表明，优化后的IF-FC系统的可攻击时间延长了30％，攻击精度提高了约50％。本文所提出的设计准则与方法对其它非空-空射击模态的IFFC系统仍有普遍意义。     

The water cycle in closed ecological systems: Perspectives from the Biosphere 2 and Laboratory Biosphere systems

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.     

Plant mineral nutrition,gas exchange and photosynthesis in space: A review

Successful growth and development of higher plants in space rely on adequate availability and uptake of water and nutrients, and efficient energy distribution through photosynthesis and gas exchange. In the present review, literature has been reviewed to assemble the relevant knowledge within space plant research for future planetary missions. Focus has been on fractional gravity, space radiation, magnetic fields and ultimately a combined effect of these factors on gas exchange, photosynthesis and transport of water and solutes.     

基于支持向量机回归和RBF神经网络的PID整定

针对工业控制领域中非线性系统控制,在基于梯度下降法的RBF网络PID整定的基础上,对整定算法作出改进,控制目标不再是使当前跟踪误差最小,而是使当前跟踪误差和下一时刻跟踪误差的平方和最小。实现过程为:先由RBF神经网络在线辨识被控对象离散模型,得到被控对象的Jacobian信息,采用梯度下降法对PID控制器参数进行初步整定;然后,将系统跟踪误差和PID参数输入支持向量机模型,通过回归预测系统下一时刻的误差,改进的整定算法利用预测误差信息对参数进行再整定。仿真结果表明,引入支持向量机回归优化的RBF神经网络PID整定收敛速度更快,精度更高,跟踪性能优于RBF神经网络PID整定。     

Comparison of three soil-like substrate production techniques for a bioregenerative life support system

It is very important to recycle the inedible biomass of higher plants to improve the closure of bioregenerative life support system (BLSS). Processing candidate higher plant residues into the soil-like substrate (SLS) as the plant growth medium is a promising way to achieve. In this study, three different processing techniques of SLSs, using residues of wheat and rice as feedstock, were compared. As for the first traditional technique, SLS1 was obtained by successive conversion of wheat straw by oyster mushrooms and worms. In the other two methods, SLSs were produced with aerobic fermentation (SLS2) or anaerobic fermentation (SLS3) followed by worm conversion. The changes in SLS cellulose, lignin, available elements and pH were measured during the production processes. The maturity was evaluated by the value of C/N. The fertilities were compared in terms of available elements contents and lettuce productivities. The results indicated that the second technique was optimal, whose process cycle was 30 days less than that of SLS1. The total cellulose and lignin degradation of SLS2, achieved 98.6% and 93.1% during the 93-days-processing, and the lettuce productivity reached 12.0 g m⁻² day⁻¹.     

基于CSDB的装甲装备IETM技术研究

引入S1000D国际规范制作IETM,体现了装备全寿命信息管理(CALS)的思想。CSDB是S1000D规范的核心概念,所存储的技术信息能实现"一次生成、多次使用"的目标,存储有DM、PM等信息对象,负责信息对象的存储和管理工作。研究了基于CSDB的装备IETM技术,对加快装甲装备保障信息化建设的作用和意义重大。     

Technology challenges for space interferometry: The option of mid-infrared integrated optics

Nulling interferometry is a technique providing high angular resolution which is the core of the space missions Darwin and TPF. The first objective is to reach a deep degree of starlight cancelation in the range 6–20 μm, in order to observe and to characterize the signal from an earth-like planet. Among the numerous technological challenges involved in these missions, the question of the beam combination and wavefront filtering has an important place. A single-mode integrated optics (IO) beam combiner could support both the functions of filtering and the interferometric combination, simplifying the instrumental design. Such a perspective has been explored in this work within the project Integrated Optics for Darwin (IODA), which aims at developing a first IO combiner in the mid-infrared. The solutions reviewed here to manufacture the combiner here are based on infrared dielectric materials on one side, and on metallic conductive waveguides on the other side. With this work, additional inputs are offered to pursue the investigation on mid-infrared photonics devices.     

Effects of lighting and air movement on temperatures in reproductive organs of plants in a closed plant growth facility

Temperature increases in plant reproductive organs such as anthers and stigmas could cause fertility impediments and thus produce sterile seeds under artificial lighting conditions without adequately controlled environments in closed plant growth facilities. There is a possibility such a situation could occur in Bioregenerative Life Support Systems under microgravity conditions in space because there will be little natural convective or thermal mixing. This study was conducted to determine the temperature of the plant reproductive organs as affected by illumination and air movement under normal gravitational forces on the earth and to make an estimation of the temperature increase in reproductive organs in closed plant growth facilities under microgravity in space. Thermal images of reproductive organs of rice and strawberry were captured using infrared thermography at air temperatures of 10–11 °C. Compared to the air temperature, temperatures of petals, stigmas and anthers of strawberry increased by 24, 22 and 14 °C, respectively, after 5 min of lighting at an irradiance of 160 W m⁻² from incandescent lamps. Temperatures of reproductive organs and leaves of strawberry were significantly higher than those of rice. The temperatures of petals, stigmas, anthers and leaves of strawberry decreased by 13, 12, 13 and 14 °C, respectively, when the air velocity was increased from 0.1 to 1.0 ms⁻¹. These results show that air movement is necessary to reduce the temperatures of plant reproductive organs in plant growth facilities.     

基于数理统计的航材备件预测方法研究

备件预测是航空公司备件订货和供货方零部件生产计划的基础,本文提出以数理统计方法来判断附件寿命分布形式,对附件寿命和故障率进行估算,并据此给出航材备件需求量及其保障率预测模型,并运用实例进行了验证。