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241.
Single Pilot Operations(SPO), as a NextGen concept of operation, can save both crew costs and human resources for airlines, and has attracted the attention of aviation researchers. To explore in advance the problems that the introduction of SPO into the aviation system would bring,the Human-Centered Design(HCD) approach has been widely used in the development of SPO. A systematic review of the progress of HCD approach in SPO research can promote further development of SPO. In this paper, the lit...  相似文献   
242.
Volume visualization can not only illustrate overall distribution but also inner structure and it is an important approach for space environment research. Space environment simulation can produce several correlated variables at the same time. However, existing compressed volume rendering methods only consider reducing the redundant information in a single volume of a specific variable, not dealing with the redundant information among these variables. For space environment volume data with multi-...  相似文献   
243.
As a data-driven approach, Deep Learning(DL)-based fault diagnosis methods need to collect the relatively comprehensive data on machine fault types to achieve satisfactory performance. A mechanical system may include multiple submachines in the real-world. During condition monitoring of a mechanical system, fault data are distributed in a continuous flow of constantly generated information and new faults will inevitably occur in unconsidered submachines, which are also called machine increments....  相似文献   
244.
A 2% scale, cruising version of a 450-seat class Blended-Wing-Body(BWB) transport was tested in the China Aerodynamic Research and Development Center’s FL-26 2.4-by-2.4-meter subsonic wind tunnel. The focus of the wind tunnel test was to investigate the aerodynamic performance of the latest BWB transport design, which would also aid in choosing a final engine arrangement in the three most potential engine integration layouts. The wind tunnel model can be tested with and without the nacelle and h...  相似文献   
245.
The stable range of operation for the centrifugal compressor significantly influences the dynamic, economic, and environment-friendly characteristics of power systems. A deep understanding of the characteristics of instability evolution is necessary to improve the compressor stability. A centrifugal compressor equipped with a vaneless diffuser is experimentally investigated using highresponse static-pressure measurements. The results obtained indicate that three typical rotationalspeed ranges ex...  相似文献   
246.
Ultrasonic surface rolling process(USRP) is one of the effective mechanical surface enhancement techniques. During the USRP, unstable static force will easily do harm to the surface quality. In order to achieve a higher surface quality on the part with a curved surface, an active and passive compliant USRP system has been developed. The compliant USRP tool can produce the natural obedience deformation along the part surface. Force control based on the fuzzy Proportional-integral-derivative(PID) ...  相似文献   
247.
Traditionally, numerical trajectory integration for shooting equation calculation and iterations for shooting with randomly guessed initial solutions deteriorate the real-time performance of indirect methods for on-board applications. In this study, the indirect method is improved to achieve real-time trajectory optimization of fuel-optimal powered planetary landings with the help of analytical shooting equation derivations and a practical homotopy technique. Specifically, the contributions of t...  相似文献   
248.
The spontaneous growth and evolution mechanism of metal whiskers have long been scientific problems. With the development of the integration of electronic and electrical productions,short circuits and system failures are raised by metal whiskers continuously. In the meantime, the related theories and mechanisms of whiskering problem are still vague, leading to a deficiency in the studies of environmental factors influencing the whisker phenomenon. Besides, the extreme environments such as aerosp...  相似文献   
249.
There is a lack of quantitative flying qualities assessment requirements for unmanned combat aerial vehicles. The mission-oriented flying qualities evaluation approach can make up for the deficiencies of existing flying qualities specifications. Considering the control characteristics and mission requirements of autonomous control unmanned combat aerial vehicles, flying qualities assessment tasks are designed and performance standards are developed on the basis of manned aircraft flying qualitie...  相似文献   
250.
Ultrasonic vibration-assisted technology is widely utilized in the performance research and manufacturing process of metallic materials owing to its advantages of introducing highfrequency acoustic systems. However, the acoustic plasticity constitutive model and potential mechanism, involving Ti3Al intermetallic compounds, have not yet been clarified. Therefore, the Ultrasonic-K-M hybrid acoustic constitutive model of Ti3Al was established by considering the stress superpos...  相似文献   
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