基于自适应控制的大型客机编队飞行一致性控制

研究解决基于多变量自适应控制的大型客机编队飞行一致性控制问题.考虑到长机和僚机都存在参数不确定和外界扰动不确定性,同时考虑大型客机之间的分布式通信拓扑结构,基于代数图论思想,提出一种状态反馈状态跟踪多变量自适应控制方法,解决了大型客机编队飞行分布式一致性控制问题.该一致性问题中的稳定性和渐近跟踪特性通过Lyapunov函数法进行了证明,保证了僚机能够跟踪长机的飞行状态.对大型客机编队飞行一致性控制问题进行数值仿真的结果表明,基于多变量自适应控制的大型客机分布式一致性策略比固定增益控制策略具有更好的跟踪性和鲁棒性.     

基于CAEPIPE的空气导管应力分析与补偿

在考察大型客机空气导管结构尺寸、材料物性参数、工作条件及补偿方式的基础上，基于CAEPIPE软件建立了空气导管引气系统计算模型；选用米塞斯（VONMIESE）应力准则，进行了应力计算分析；并系统研究了补偿方式、补偿位置等因素对导管应力性能的影响。研究工作对于我国大型客机空气导管系统的设计优化具有参考价值。     

民机客舱热载荷的数值计算

以桌型客机为例，将客舱复杂围护结构划分为三部分。据此建立各区域单元结构的三维数值计算模型，并对不同外界环境下客舱的热流密度及传热量进行了数值仿真。结果与传统计算方法吻合良好，研究工作对于我国大型飞机热载荷的计算具有参考价值。     

基于FLOWMASTER软件的引气系统仿真分析

为准确模拟飞机导管引气系统在各工况下的运行状态，在研究飞机引气系统结构及流体网络算法原理的基础上，基于一维流体仿真技术建立了引气系统计算模型，根据实际工况对系统进行了稳态和瞬态分析。重点考察了系统中各主要元件的运行情况及节点的压力、温度等关键参数的变化规律。仿真结果表明，系统及各主要元件均满足设计与控制要求，可为我国民用客机导管系统的优化设计提供一定的理论参考。     

车辆转弯制动ABS模糊控制及稳定性仿真分析

在Matlab／Simlink下建立了八自由度车辆系统的仿真模型。采用模糊控制方法，设计了基于滑移率的ABS控制算法。针对车辆转弯制动工况，对15m／s、20m／s、25m／s三种车速进行了仿真分析。仿真结果表明所建立的ABS控制器能有效提高车辆的制动性能以及中低车速下的稳定性，但定性分析表明车辆在高速工况下出现不稳定现象。为此利用稳定性判定式，对车辆转弯制动ABS控制下的稳定性做了定量判定。判定结果表明，高速时车辆仅有ABS控制并不能达到稳定性控制的要求。     

空间智能桁架的传感器作动器位置优化和分散化自适应模糊振动控制

提出了作动器和传感器配置优化和分散化自适应控制方法以解决桁架系统的振动控制问题.建立了主动杆的机电耦合方程,提出了不依赖于控制方法的优化准则,采用遗传算法得到了作动器和传感器在大型空间智能桁架系统中的最优位置.而且设计了一种分散化自适应模糊振动控制器来控制大型空间智能桁架系统.推导了大型空间智能桁架系统考虑剩余模态影响的动力学方程,利用滑模控制方法改进了自适应模糊控制方案,并以T字型桁架结构为例进行了验证性实验.实验结果表明,遗传算法对于作动器和传感器的配置优化是可靠的、有效的,自适应模糊控制器能有效地抑制大型空间智能桁架系统的振动,且没有控制溢出和观测溢出问题.     

基于4D航迹的飞机连续下降运行飞行引导技术

连续下降运行(continuous descent operation,CDO)是减少大型飞机燃油消耗、降低噪声污染和二氧化碳排放的进近方式.但由于连续下降进近增加了飞机进场航迹的不确定性,降低了跑道容量,限制了CDO的实施.为了在高密度空域环境下实施CDO,需要借助于四维航迹运行技术,利用4D航迹预测和飞行引导系统实现可定时到达的精准飞行引导,降低CDO航迹的不确定性.本文给出了一种基于4D航迹的大型飞机飞行引导系统架构,介绍了4D航迹的描述方法和多约束情况下4D航迹规划过程;为提高估计到达时间的预测精度,提出了一种基于伪航路点的地速计算方法;最后给出了基于要求到达时间(required time of arrival,RTA)和纵向位置误差的速度调整策略.本文以某型运输机为例,进行了基于4D航迹的连续下降进近仿真,仿真结果验证本文所提引导架构和算法能够为大型客机提供面向定时到达的精确4D飞行引导能力.     

液体火箭增压输送系统多学科动力学研究

通过多学科动力学建模方法研究,首先建立了平台供气系统机械、气动与控制动力学特征模型,并对不同工况下系统动态性能进行数值仿真,着重研究调压压力、系统阻尼、充压方式、管路特性等对系统动态稳定性的影响,为系统动态稳定性分析及稳定性改进提高提供指导;最后结合某型号飞行过程中增压系统故障问题,建立了冷氦增压系统机械、气动、电磁、热与控制多学科动力学仿真分析模型,通过系统流量及压降分析进行故障定位,进一步探讨多学科动力学仿真在增压输送系统中的应用.     

基于AVR单片机的车载DVD/VCD面板组件自动检测系统

本文提供了一种基于AVR单片机的车载DVD／VCD面板组件自动检测系统设计方案，介绍了目前国内相关检测技术方法，分析了其不足之处和未来的发展方向，给出新设计系统的构成和工作原理。该检测系统已经用于深圳某大型港资电子公司的生产线，与传统检测方法相比较极大地提高了工作效率和可靠性。     

零质量射流技术及其应用研究进展

零质量射流自20世纪90年代作为一项主动流动控制技术应用以来，由于其具有结构紧凑，无需气源管道等独特的优势，短时间就引起了众多研究者的广泛关注，成为目前流体力学研究的一个热点．主要从零质量射流在静止环境中的发展、零质量射流和横流的相互作用及其在控制分离流动方面的应用等三个方面进行了回顾，介绍了零质量射流在静止和有横流条件下的涡环／对发展规律、空间流场结构以及几个主要无量纲参数的影响规律，最后介绍了零质量射流在控制圆柱尾迹、翼面流动分离以及在MAV／UAV上的应用情况．     

3MW海上风力发电机机舱热平衡设计

以3MW海上风力发电机为研究对象，在考察其机舱布置结构、主要部件散热情况及环境要求的基础上，对机舱进行了热平衡设计，建立了机舱热平衡方程；提出了舱内部件载荷、机舱内外对流换热系数、舱内正压维持新风量的计算方法；获得了射流冷却方式下的舱内热载荷变化特性；并研究了舱内外空气温度、速度、舱体表面灰度等因素对机舱热平衡的影响。研究工作对于大容量风力发电冷却系统的设计优化具有参考价值。     

新型水环热泵低温新风处理系统的炯分析

应用能量和炯分析方法，对一种用于独立新风空调系统的新型水环热泵低温新风处理系统进行能量评价。通过实例对新风系统的能量和炯的传递与转换进行分析计算，并与采用冰蓄冷系统和冷水机组作为新风处理设备冷源的两种低温新风系统进行比较，结果表明采用水环热泵新风机组的独立新风处理系统，其能效比和炯效率较其它两种系统高，该系统良好的节能特性将有助于独立新风系统在我国的应用和推广。     

The atmospheric environment—an introduction

The atmosphere is part of the environment with which the human organism is permanently confronted. Epidemiological research investigates the occurrence of effects on morbidity and mortality due to heat, cold, air pollution and changes in the weather. Concentrating on aspects of the environment relevant for medical questions, three major complexes of effects can be discriminated: the complex conditions of heat exchange, the direct biological effects of solar radiation, and air pollution. Biometeorological knowledge can serve to assess the atmospheric environment, and can also be of help in the field of preventive planning, to conserve and develop the climate as a natural resource with regard to man's health, well-being and performance.     

电信空调冷却塔供冷系统节能应用

根据电信机楼的空调负荷特点，在冬季和部分过渡季节，选择使用冷却塔加板式换热器的间接式免费供冷空调系统为电信机楼提供冷量。介绍了冬季机房空调送风温度和冷却塔供冷温度的确定，分析了冷却塔供冷温度对冷却塔运行消耗的影响。通过预测计算确定冷却塔免费制冷的的运行时间及节能效果。并引入了冷负荷供需指数的概念，经过现场测试计算得出江苏电信第二枢纽工程中影响该指数的三个因素，最后总结了江苏电信免费制冷技术的节能情况和应用潜力。     

The impact of climate change on human health: Some international implications

The objective of this study is to discuss the potential impact of a global warming on various aspects of human health. Changes in heat-related mortality are estimated for four countries: the United States, Canada, the People's Republic of China and Egypt. In addition, the potential confounding impact of increased air pollution is considered. Finally, a framework to analyze two vector-borne diseases, onchocerciasis and malaria, which may spread if temperatures increase, is discussed. Our findings suggest that heat-related mortality is estimated to rise significantly in all four countries if the earth warms, with the greatest impacts in China and Egypt. The most sensitive areas are those with intense but irregular heat waves. In the United States, air pollution does not appear to impact daily mortality significantly when severe weather is present, although it seems to have a slight influence when weather conditions are not stressful.     

The importance of radioactivity in geoscience and mining

Almost simultaneously with Roentgen rays, natural radioactivity was discovered. Its investigation led to important fundamentals of the geosciences: petrophysics, terrestrial heat flow, isotope geology, and absolute geological chronology. In applied geophysics and geology, exploration of radioactive ores and of tectonic faults, and radiometric well loggings, are used. Production of radioactive water and mining for uranium ores are discussed, including their development (especially in the Saxon ore mountains) and the consequences on health (radon in underground air and houses). Disposal of radioactive waste is touched on briefly.     

Thermal conductivity of wax comb and its effect on heat balance in colonial honey bees (Apis mellifera L.)

Summary Wax comb was found to have a thermal conductivity of 0.36×10^–3 cal/cm sec °C. At low air temperatures, honey bees,Apis mellifera L., form clusters inbetween the combs in their nests. The combs provide insulation and the bee behavior actually increases the insulating effectiveness of the combs. When they form a compact living layer over the wax comb, the conductivity can be reduced to 0.065×10^–3 cal/cm see °C. Some aspects of the role of the wax comb in heat balance are examined in this paper.     

Indoor climate

In industrialized countries most of the time is spent indoors. The basic ambient parameters for a thermally comfortable indoor climate are air temperature, air velocity, humidity and radiation pattern. Besides the thermal component, the concentrations of air pollutants in the indoor air are also of importance for wellbeing and health. Their levels are influenced both by the outdoor concentrations and the indoor emissions. The increasing use of air conditioning systems in many cases has not resulted in improving the indoor climate but causes a wide range of irritations and health problems summarized as sick building syndrome.     

Structure and function of small heat shock/alpha-crystallin proteins: established concepts and emerging ideas

Small heat shock/alpha-crystallin proteins are defined by conserved sequence of approximately 90 amino acid residues, termed the alpha-crystallin domain, which is bounded by variable amino- and carboxy-terminal extensions. These proteins form oligomers, most of uncertain quaternary structure, and oligomerization is prerequisite to their function as molecular chaperones. Sequence modelling and physical analyses show that the secondary structure of small heat shock/alpha-crystallin proteins is predominately beta-pleated sheet. Crystallography, site-directed spin-labelling and yeast two-hybrid selection demonstrate regions of secondary structure within the alpha-crystallin domain that interact during oligomer assembly, a process also dependent on the amino terminus. Oligomers are dynamic, exhibiting subunit exchange and organizational plasticity, perhaps leading to functional diversity. Exposure of hydrophobic residues by structural modification facilitates chaperoning where denaturing proteins in the molten globule state associate with oligomers. The flexible carboxy-terminal extension contributes to chaperone activity by enhancing the solubility of small heat shock/alpha-crystallin proteins. Site-directed mutagenesis has yielded proteins where the effect of the change on structure and function depends upon the residue modified, the organism under study and the analytical techniques used. Most revealing, substitution of a conserved arginine residue within the alpha-crystallin domain has a major impact on quaternary structure and chaperone action probably through realignment of beta-sheets. These mutations are linked to inherited diseases. Oligomer size is regulated by a stress-responsive cascade including MAPKAP kinase 2/3 and p38. Phosphorylation of small heat shock/alpha-crystallin proteins has important consequences within stressed cells, especially for microfilaments.     

On the structure of Carnot's theory of heat

A simple connection is pointed out between the theory of heat formulated in Sadi Carnot's: Réflexions sur la puissance motrice du feu (1824) and the later Kelvin-Clausius thermodynamics. In both theories two well-defined quantities, a heat function and a work function, exist and can be calculated by integrating along a reversible path. In thermodynamics the work function (energy) is conserved, whereas the heat function (entropy) increases by irreversible processes. In Carnot's theory the heat function is conserved, whereas the work function decreases, so that in this theory the irreversible process is characterized by a loss of work.