一种具有电压支撑功能的改进无功注入策略

电压跌落是输配电系统面临的最严重的问题之一。随着分布式光伏电源在电力系统中的渗透率越来越高,国内外最新标准要求光伏逆变器必须具备低电压穿越能力。为了消除有功功率振荡,在传统的正/负序控制基础上提出了一种改进的有功/无功注入策略;针对现有电压支撑方法缺乏电压抬升范围控制,将三相电压幅值作为控制目标,详细推导了适用于不同电压跌落情况下的数学模型,得出为保证各相电压均保持在安全运行范围之内所需注入无功功率参考值。仿真结果验证了所提策略的正确性和有效性。     

海上待战模式下的导弹保障辅助决策模型

在大规模、高强度、海上待战的作战模式下,海军导弹武器装备的高效及时补充,对于作战部队战斗力的恢复和持续具有越来越重要的意义。文章根据时效性和经济性原则,围绕保障关系的决策建立辅助决策模型,帮助指挥员快速地、科学地确定保障关系,为制定精确、快捷、高效的保障方案提供辅助决策,具有一定的参考和借鉴意义,并通过实例对模型进行了验证。     

基于灰色近似支持向量机的加速度计参数预测

温度、振动等环境载荷使得石英挠性加速度计参数产生漂移,直接影响了惯导系统的测量精度和性能,石英挠性加速度计参数变化趋势为非线性的,很难用常规的建模方法进行趋势预测。基于灰色理论适合进行小样本、贫信息不确定型系统建模以及近似支持向量机不需要求解二次规划就能求得非线性模型参数的优点,提出了基于灰色近似支持向量机进行石英挠性加速度计参数预测的方法。为了验证该方法的有效性,针对自然贮存的加速度计进行了固定周期的参数标定,结果表明灰色近似支持向量机具有很好的预测效果。     

基于有限元分析的综合支架结构设计与优选

本文在分析海洋平台防爆加热器橇块综合支架结构特点的基础上,通过有限元法对综合支架进行强度能力分析,找到该支架结构设计上存在的问题并作了相应的改进设计,使得综合支架的结构在满足强度和刚度的同时减轻了整体的重量,在材料的利用上趋于优化的设计;通过对综合支架的有限元模型施加不同的惯性力.得出不同载荷下综合支架应力变化规律,从而确定出综合支架所能承受的最大惯性力.     

老龄飞机的故障控制

介绍了老龄飞机的故障控制方式，阐述了预防性维修和及时处理故障在老龄飞机保障中的重要性。     

闭合薄壁剖面杆刚度计算的有限元素法

利用有限元法对飞机闭合薄壁剖面杆结构进行刚度计算，其结果与全尺寸试验值吻合较好。     

Integration of lessons from recent research for “Earth to Mars” life support systems

Development of reliable and robust strategies for long-term life support for planetary exploration must be built from real-time experimentation to verify and improve system components. Also critical is incorporating a range of viable options to handle potential short-term life system imbalances. This paper revisits some of the conceptual framework for a Mars base prototype which has been developed by the authors along with others previously advanced (“Mars on Earth^®”) in the light of three years of experimentation in the Laboratory Biosphere, further investigation of system alternatives and the advent of other innovative engineering and agri-ecosystem approaches. Several experiments with candidate space agriculture crops have demonstrated the higher productivity possible with elevated light levels and improved environmental controls. For example, crops of sweet potatoes exceeded original Mars base prototype projections by an average of 46% (53% for best crop) ultradwarf (Apogee) wheat by 9% (23% for best crop), pinto bean by 13% (31% for best crop). These production levels, although they may be increased with further optimization of lighting regimes, environmental parameters, crop density etc. offer evidence that a soil-based system can be as productive as the hydroponic systems which have dominated space life support scenarios and research. But soil also offers distinct advantages: the capability to be created on the Moon or Mars using in situ space resources, reduces long-term reliance on consumables and imported resources, and more readily recycling and incorporating crew and crop waste products. In addition, a living soil contains a complex microbial ecosystem which helps prevent the buildup of trace gases or compounds, and thus assist with air and water purification. The atmospheric dynamics of these crops were studied in the Laboratory Biosphere adding to the database necessary for managing the mixed stands of crops essential for supplying a nutritionally adequate diet in space. This paper explores some of the challenges of small bioregenerative life support: air-sealing and facility architecture/design, balance of short-term variations of carbon dioxide and oxygen through staggered plantings, options for additional atmospheric buffers and sinks, lighting/energy efficiency engineering, crop and waste product recycling approaches, and human factor considerations in the design and operation of a Mars base. An “Earth to Mars” project, forging the ability to live sustainably in space (as on Earth) requires continued research and testing of these components and integrated subsystems; and developing a step-by-step learning process.     

金融服务滞后产业发展的成因及对策——以航空业为例

分析了在战略产业发展过程中金融业服务滞后的各种表现，从战略产业经济结构调整本身、风险约束和金融宏观政策传导三个方面剖析了金融服务滞后的原因。以民用航空制造业的发展为例，用博弈论对金融在支持战略产业发展过程中的两难状况作了理论和实证分析，提出金融支持战略产业的发展是金融发展的最优选择的观点。最后从金融体系、资金投入和金融服务等方面提出相应的对策建议。     

Assessing the feasibility of involving gaseous products resulting from physicochemical oxidation of human liquid and solid wastes in the cycling of a bio-technical life support system

The study addresses the possible ways of involving gaseous products produced by “wet” incineration of human wastes mixed with H₂O₂ in an alternating electric field in the cycling of the physical model of a bio-technical life support system (BTLSS). The resulting gas mixture contains CO₂ and O₂, which are easily involved in the cycling in the closed ecosystem, and NH₃, which is unacceptable in the atmosphere of the BTLSS. NH₃ fixation has been proposed, which is followed by nitrification and involvement of the resulting products in the mass exchange of the closed system. Experiments have been performed to show that plants can be grown in the atmosphere resulting from the closing of the gas loop that includes a physicochemical installation and a growth chamber with plants representing the phototrophic compartment of the BTLSS. The results of the study suggest the conclusion that the proposed method of organic waste oxidation can be a useful tool in creating a physical model of a closed-loop integrated BTLSS.     

用于评定火炮火力支援效果的马尔科夫模型

根据炮兵作战理论和实际作战流程，建立了用于评定间瞄武器进行火力支援的作战效能模型。该模型不仅可以比较不同火炮系统的作战效能，还可通过修改模型参数使其能反映不同的作战强度，对炮兵的战术决策有一定的参考意义。