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《Air & Space Europe》1999,1(1):42-44
Alternative Flight Management System (FMS) human interface concepts are becoming increasingly important to investigate as the complexities of understanding and operating this equipment continue to burden and confuse an already inundated pilot. Rockwell Collins, Inc. has designed an advanced FMS display/interface that will significantly reduce and/or eliminate human interface problems between users and the FMS. Results from human factors investigations for a limited set of FMS functions reveal statistically significant findings at the 95th level of confidence favoring the Advanced FMS Interface display format. The Advanced FMS Interface display format produced quicker reaction times and lower levels of mental workload than the a conventional Control Display Unit (CDU) type FMS.Furthermore, statistically significant findings at the 98th level of confidence for three subjective measures, Usability, Learnability, and Overall Attitude lean in favor of this type of FMS display format. These statistically significant findings lead us to believe that this Advanced FMS Interface display format has great potential for significantly reducing and/or eliminating human interface problems between users and the FMS while at the same time reducing pilot mental workload. 相似文献
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《Air & Space Europe》1999,1(1):24-25
Space - or, more precisely, space technologies which enable us to enter and make use of space for a wide range of purposes - concerns us all for many reasons. 相似文献
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《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1999,23(5-6):925-936
This review describes dynamical evidence for massive black holes (BHs) at the centers of galaxies. BHs appear to be a common if not ubiquitous feature of local galactic spheroids, with a mean mass that is roughly 0.5% of the parent stellar spheroid mass. This mass is large enough that the formation and evolution of central BHs has had a significant influence on the inner stellar density profile. For example, low-density, core-type profiles may have been created by the scouring action of binary BH pairs, whose orbital decay ejects stars from the center of the galaxy. Or, BHs may have grown substantially by gas accretion, pulling in surrounding stars and creating the cuspy cores and power laws that are seen in spheroids. If BHs are ubiquitous in galactic spheroids at the above mass ratio, their total local mass density is comparable to that implied by the energy density of QSO photons, suggesting that these local BHs are the long-sought fossil BHs of QSO central engines. However, QSOs are much rarer per unit co-moving volume than local BHs, unless one equates them to just the massive BHs found in rare and massive local spheroids. The resultant BH masses exceed typical QSO BH mass estimates by nearly a factor of 10, suggesting that BHs have grown in mass by roughly that factor since the QSO era. At least some of that growth might have occurred as protogalaxies grew in mass by mergers, and their BHs also merged and grew apace. 相似文献
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航天器太阳帆板展开过程的最优控制 总被引:10,自引:0,他引:10
本文讨论航天器太阳帆板展开过程中主体姿态的最优控制问题. 利用多体动力学与最优控制理论建立数学模型, 考虑系统的非完整约束特性, 提出太阳帆板展开过程的最优控制算法. 通过数值仿真, 表明该方法对太阳帆板展开姿态控制的有效性. 相似文献
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针对多光谱红外探测器,对复杂背景条件下红外弱小目标检测算法进行了研究。根据弱小目标缺乏纹理等相关信息的特点,给出了一种用于多光谱图像的弱小目标检测算法。对多光谱图像,构建数据立方体,对多光谱信息建立稳定的目标特征向量,用多光谱背景抑制滤波器以提升图像信噪比,将一种基于统计判别的低信噪比条件下红外序列图像弱小目标检测算法与传统多级假设检验跟踪(MHT)算法综合,形成了改进的连续帧目标检测跟踪算法,对波门内疑似目标点用引入多光谱信息建立的特征向量进行目标的非监督检测判决。实验结果证明:在低信噪比下该算法能有效检测跟踪弱小目标,在保证检测概率前提下可有效抑制虚警,极大地降低了后续跟踪算法的计算爆炸风险。 相似文献
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