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211.
Robustness of transportation networks is one of the major challenges of the 21st century. This paper investigates the resilience of global air transportation from a complex network point of view, with focus on attacking strategies in the airport network, i.e., to remove airports from the sys-tem and see what could affect the air traffic system from a passenger's perspective. Specifically, we identify commonalities and differences between several robustness measures and attacking strate-gies, proposing a novel notion of functional robustness: unaffected passengers with rerouting. We apply twelve attacking strategies to the worldwide airport network with three weights, and eval-uate three robustness measures. We find that degree and Bonacich based attacks harm passenger weighted network most. Our evaluation is geared toward a unified view on air transportation net-work attack and serves as a foundation on how to develop effective mitigation strategies. 相似文献
212.
O.V. Postylyakov I.B. Belikov N.F. Elansky A.S. Elokhov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,37(12):2231-II
To investigate the vast area of Russia, a mobile scientific facility based in a railway carriage was developed. It is capable to perform continues measurements being coupled in a passenger train traveling along railroads. It was first equipped with a spectrometer for remote sensing of ozone and nitrogen dioxide in the atmosphere for the transcontinental observations into the chemistry of the atmosphere-4 expedition performed from February 18 to March 5, 1998. A twilight DOAS method, which was applied for retrieval of the nitrogen dioxide profiles basing on spectral measurements at the visible wavelengths (434–451 nm), is described in the paper. Main features of a new algorithm for retrieval of the ozone profile and total content using the differential structure of the UV spectrum (310–335 nm) are presented. The ozone and nitrogen dioxide contents are obtained and shortly validated against available alternative data. 相似文献
213.
Due to rapid development in the past decade, air transportation system has attracted considerable research attention from diverse communities. While most of the previous studies focused on airline networks, here we systematically explore the robustness of the Chinese air route network, and identify the vital edges which form the backbone of Chinese air transportation system. Specifically, we employ a memetic algorithm to minimize the network robustness after removing certain edges, and hence the solution of this model is the set of vital edges. Counterintuitively, our results show that the most vital edges are not necessarily the edges of the highest topological importance, for which we provide an extensive explanation from the microscope view. Our findings also offer new insights to understanding and optimizing other real-world network systems. 相似文献
214.
飞机敏捷性与空空导弹攻击区综合研究 总被引:4,自引:0,他引:4
基于飞行力学与控制,导弹制导与攻击区,计算机仿真等理论和技术,针对飞机的三轴方向提出了一种敏捷性矢量的估算方法,建立了求解攻击区的弹道方程组,并利用二分法求解导弹攻击区,通过数值计算求得两种情况,(即无敏捷性载机地敏捷性目标,敏捷性载机对无敏捷性目标)下空空导弹攻击区,并对计算结果进行了分析,得出飞机敏捷性对导弹攻击区和影响规律和最优攻防策略,为空战决策和新型飞机的预研设计提供了参考。 相似文献
215.
Nagaraja Kamsali B.S.N. Prasad Jayati Datta 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009,44(9):1067-1078
The experimentally measured ground level atmospheric electrical conductivity is validated from a simplified ion–aerosol model for which the inputs are ionization rate from surface radioactivity, aerosol density and meteorological parameters. Also estimated from the model is the reduction in conductivity for assumed aerosol levels. It is seen that for an increase of ambient aerosols by threefold the percent reduction in conductivity is 7% and it is 10% for an increase by sixfold. Thus, the variations in the measured ground level conductivity can be used to examine the atmospheric pollution, if any. 相似文献
216.
万晓云 《中国民航飞行学院学报》2013,(5):34-37
大气数据系统是飞机重要的机载系统。本文结合系统原理、工程技术资料和自身维护经验,对A320系列飞机大气数据系统日常维护中的一些常见故障和特殊故障进行分析,给出维护建议,并对系统维护中的注意事项进行提示与强调。 相似文献
217.
纳米光催化技术在客机座舱空气质量控制中的应用 总被引:1,自引:0,他引:1
纳米光催化技术是一种新型的空气净化技术,近年来已成为空气净化领域的研究热点之一。本文简要介绍了纳米光催化技术的发展历史、净化机理以及国内外的研究进展;分析了实际应用中存在的问题;并指出了纳米光催化技术在客机座舱空气质量控制中的应用前景。 相似文献
218.
介绍了“大工程观”教育理念的实质及特点,结合中国民航大学与华北空管局实施管制学员雷达管制实践能力联合培养的教学试点改革案例,指出应积极推进雷达管制实践教学模式改革,以应对行业快速发展对空管人才综合素质的更高要求. 相似文献
219.
Intelligent checking model of Chinese radiotelephony read-backs in civil aviation air traffic control 总被引:1,自引:0,他引:1
Federal Aviation Administration (FAA) and NASA technical reports indicate that the misunderstanding in radiotelephony communications is a primary causal factor associated with operation errors, and a sizable proportion of operation errors lead to read-back errors. We introduce deep learning method to solve this problem and propose a new semantic checking model based on Long Short-Time Memory network (LSTM) for intelligent read-back error checking. A mean-pooling layer is added to the traditional LSTM, so as to utilize the information obtained by all the hidden activation vectors, and also to improve the robustness of the semantic vector extracted by LSTM. A MultiLayer Perceptron (MLP) layer, which can maintain the information of different regions in the concatenated vectors obtained by the mean-pooling layer, is applied instead of traditional similarity function in the new model to express the semantic similarity of the read-back pairs quantitatively. The K-Nearest Neighbor (KNN) classifier is used to verify whether the read-back pairs are consistent in semantics according to the output of MLP layer. Extensive experiments are conducted and the results show that the proposed model is more effective and more robust than the traditional checking model to verify the semantic consistency of read-backs automatically. 相似文献
220.
《中国航空学报》2023,36(4):366-386
In this work, the primary focus is to identify potential technical risks of Artificial Intelligence (AI)-driven operations for the safety monitoring of the air traffic from the perspective of speech communication by studying the representative case and evaluating user experience. The case study is performed to evaluate the AI-driven techniques and applications using objective metrics, in which several risks and technical facts are obtained to direct future research. Considering the safety–critical specificities of the air traffic control system, a comprehensive subjective evaluation is conducted to collect user experience by a well-designed anonymous questionnaire and a face-to-face interview. In this procedure, the potential risks obtained from the case study are confirmed, and the impacts on human working are considered. Both the case study and the evaluation of user experience provide compatible results and conclusions: (A) the proposed solution is promising to improve the traffic safety and reduce the workload by detecting potential risks in advance; (B) the AI-driven techniques and whole diagram are suggested to be enhanced to eliminate the possible distraction to the attention of air traffic controllers. Finally, a variety of strategies and approaches are discussed to explore their capability to advance the proposed solution to industrial practices. 相似文献