Integrated multiple-model adaptive fault identification and reconfigurable fault-tolerant control for Lead-Wing close formation systems

This paper investigates the attitude and position tracking control problem for Lead-Wing close formation systems in the presence of loss of effectiveness and lock-in-place or hardover failure. In close formation flight, Wing unmanned aerial vehicle movements are influenced by vortex effects of the neighbouring Lead unmanned aerial vehicle. This situation allows modelling of aerodynamic coupling vortex-effects and linearisation based on optimal close formation geometry. Linearised Lead-Wing close formation model is transformed into nominal robust H-infinity models with respect to Mach hold, Heading hold, and Altitude hold autopilots; static feedback H-infinity controller is designed to guarantee effective tracking of attitude and position while manoeuvring Lead unmanned aerial vehicle. Based on H-infinity control design, an integrated multiple-model adaptive fault identification and reconfigurable fault-tolerant control scheme is developed to guarantee asymptotic stability of close-loop systems, error signal boundedness, and attitude and position tracking properties. Simulation results for Lead-Wing close formation systems validate the efficiency of the proposed integrated multiple-model adaptive control algorithm.     

Effects of the aluminum concentration on twin boundary motion in pre-strained magnesium alloys

We investigated the effects of Al concentration on the reciprocated motion of twin boundaries in pre-strained Mg-Al-Zn alloys through a combination of applied compression and tension,in-situ electron-backscattering diffraction observations,and high-angle annular dark-field scanning transmission electron microscopy observations.The twin growth was restricted by increased Al concentration,which resulted in the occurrence of smaller-sized twins.The reverse motion of twin boundaries was also restricted,resulting in the formation of higher fractions of secondary twins and 2-5° boundaries during reverse tension.The secondary twins and 2-5° boundaries mainly contributed to the increased ultimate tensile strength of the pre-strained Mg alloys.This effect is more significant in Mg alloys with larger pre-compression.Moreover,the increased amount of the Al solute atoms,rather than the precipitates,mainly contributed to the increased strengthening effect on the twin boundary motion.Our research contributes to development of high-strength Mg alloys by stabilizing twin boundaries.     

中低应变率下闭孔泡沫铝动态力学性能研究

为探索闭孔泡沫铝的动态力学性能与吸能特性,基于万能材料试验机和高速液压伺服材料试验机在常温下分别对闭孔泡沫铝在准静态和中应变率下(0.001~100s^-1)的动态力学性能进行了测试,分析了不同应变率、不同相对密度和不同泡沫铝基体特性下闭孔泡沫铝的应力应变曲线特征和吸能特性变化。研究结果表明:中低应变率下的纯铝基体泡沫铝并不具备应变率效应,高脆性、相对密度较小的泡沫铝具备更好的吸能特性,塑性和脆性基体泡沫铝变形带分别呈现“V”形和“X”形,脆性基体泡沫铝同样不具备应变率效应。     

Relationship among Facebook jealousy,aggression, and personal and relationship variables

In the last decade, jealousy research has focused on the Facebook jealousy; however, few studies have identified its relationship to aggression. The purpose of this study is to investigate the relationship between Facebook jealousy and aggression, and some personal and relational variables. A sample of 846 participants (516 females, 330 males) aged 18–66 years from Turkey completed the Facebook Jealousy Questionnaire, Rosenberg Self-Esteem Scale, and Buss–Perry Aggression Questionnaire. From an evolutionary perspective, gender differences in jealousy could be explained through evolution-based differences in parental investment, and that males exhibit increased jealousy in response to sexual infidelity, whereas females become jealous in response to emotional infidelity. A forced-choice question (with a choice of sexual infidelity or emotional infidelity as the more jealousy evoking) was asked to the participants in order to determine gender differences on sexual and emotional jealousy. Results indicated no significant gender differences in Facebook Jealousy scores. Self-esteem and age negatively predicted Facebook jealousy. All aggression sub-types significantly predicted Facebook jealousy. Consistent with the evolutionary perspective and previous evidence, chi-square analysis showed that males’ and females’ responses to the forced-choice question differ significantly.     

基于熵和相关接近度的混合高斯目标检测算法

针对固定模型个数的混合高斯模型的背景建模速度慢和运动目标的拖影问题,提出了一种基于Tsallis熵和相关接近度的改进混合高斯算法。该算法利用Tsallis熵对高斯模型自适应地选择模型个数,加速背景建模;对于模型匹配判断条件,不能很好地体现相邻像素点的空间相关性的情况,提出了相关接近度作为模型更新的限定条件,以去除拖影。实验结果表明,改进的算法在实时性、检测正确率方面都有较好的改进。     

跆拳道比赛中近身下劈运动运用及方法

通过2004年全国跆拳道冠军赛男子20场录像资料观察,统计实战中下劈腿技术和其他各种技术的运用情况,并对相应技术做综合分析与研究;提出了跆拳道下劈腿技术在男子跆拳道比赛中应该注意的问题,并从训练和比赛的角度对男子运动员和教练员如何提高技术与得分提出了一些参考性的建议.     

工程车辆散热调温控制系统

分析介绍工程车辆上的独立风扇结构的散热调温系统,为该系统设计了转速、温度双闭环控制结构的调温控制器,为了对发动机水温、液压油温、变矩器油温控制,引入温度优先法则.该控制系统使得发动机、液力、液压系统工作在正常的温度.     

压密灌浆在素填土地基中的应用与研究

结合工程概况及其工程地质条件,提出采用压密灌浆加固、控制灌浆量和灌浆压力、采用二次灌浆和补充灌浆法等施工措施,通过现场检测,收到了良好的灌浆效果,以推广压密灌浆在素填土地基处理中的广泛应用。     

近距离双线盾构隧道施工相互影响的监测与分析

上海外高桥电厂是我国目前单机容量最大的火力发电厂 ,两条取水隧道是二期工程的一个重要项目 ,但由于其所处地理位置的影响 ,使得设计上取水隧道之间距离较小 ,施工过程中必须进行同步监测。文中详细介绍了监测方案的实施过程 ,分析了隧道内力、隧道断面收敛变形、接触压力等随工程施工的变化规律 ,保证了取水隧道工程施工的顺利进行。