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    Development status, challenges and trends of strength technology for hypersonic vehicles
    SUN Cong
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2022, 43 (6): 527590-527590.   DOI: 10.7527/S1000-6893.2022.27590
    Abstract3122)   HTML512)    PDF(pc) (26942KB)(2303)       Save
    As a type of hi-tech weapon, hypersonic vehicle plays an important strategic role in national security and benefits. It has now become a research hotspot in the field of aerospace, and the competition is becoming increasingly fierce all over the world. Advanced material and structure design is a basic key technology to support the development of hypersonic vehicle. The strength of materials and structures in extremely severe service environments is still a key issue restricting the development of this type of aircraft. This paper reviews the structure strength problems and evolution characteristics in the field of hypersonic vehicles in the past few decades. Combined with the current vehicle model development demand and technology development trend, this paper analyzes the current situation and shortcomings of structure strength technology in supporting the development of hypersonic vehicles and discusses the new requirements, new characteristics and new methods of strength problems in this field in the future. Finally, the future development direction in the field of hypersonic vehicle structure strength is proposed after summarization.
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    Development and applications of airport avian radar: Review
    CHEN Weishi, HUANG Yifeng, CHEN Xiaolong, LU Xianfeng, ZHANG Jie
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2022, 43 (1): 24758-024758.   DOI: 10.7527/S1000-6893.2020.24758
    Abstract2666)   HTML94)    PDF(pc) (36464KB)(795)       Save
    Avian radar has become an important bird situation observation tool in airport bird strike avoidance. The origin of avian radar technology is first introduced, followed by analysis of the target characteristics of flying birds in terms of the target echo amplitude, flight speed, flight height, trajectory characteristics and micro-Doppler characteristics. Four typical airport avian radar systems, including Merlin radar, Accipiter radar, Robin radar and Aveillant radar, and the research status of the domestic avian radar technology are then introduced. Key radar technologies such as antenna, radar waveform, target detection and tracking, target recognition and classification are analyzed, and the performance of typical avian radar systems compared. In addition, the applications of avian radar are discussed with respect to the fusion of radar and photoelectric technologies, the linkage of bird detection and repellent, and the bird information analysis. Conclusions are finally drawn and prospects are made.
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    SST turbulence model improvements: Review
    Yu ZENG, Hongbo WANG, Mingbo SUN, Chao WANG, Xu LIU
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2023, 44 (9): 27411-027411.   DOI: 10.7527/S1000-6893.2022.27411
    Abstract2362)   HTML114)    PDF(pc) (3131KB)(1168)       Save

    The k-ω Shear Stress Transport (SST) turbulence model, one of the best eddy viscosity models with comprehensive performance, has been widely used in recent years. However, with the increase of problem complexity and simulation accuracy requirements, the standard SST turbulence model shows clear limitations in certain aspects, eliciting extensive improvement research. This paper reviews the improvement research of the SST model from six aspects: rotation/curvature effect, compressibility effect, shock wave unsteadiness effect, effect of anisotropy Reynolds stress, effect of stress-strain deviation, and laminar/turbulent transition effect. Meanwhile, it also briefly introduces the model improvement based on the data-driven technology in recent years, sorts out the ideas and development trends of various improvement research, expounds their applicability and limitations, and analyzes the reasons and problems affecting the improvement effect. Finally, some suggestions for future work are given.

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    Research status and prospect of fault diagnosis for gas turbine aeroengine
    LIN Jing, ZHANG Boyao, ZHANG Dayi, CHEN Min
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2022, 43 (8): 626565-626565.   DOI: 10.7527/S1000-6893.2021.26565
    Abstract2330)   HTML285)    PDF(pc) (5160KB)(1358)       Save
    Gas turbine engine is a comprehensive embodiment of the level of national science, technology and industry. Fault diagnosis is an important guarantee for its safe and reliable operation and an essential indicator of engine advancement. However, due to the complicated structure, highly integrated system, harsh service environment, variable mission profiles, the constraints of limited online testing conditions, and the poor supportability of diagnostic information acquisition, the fault diagnosis for aeroengine faces multiple challenges. In this paper, the research status in China and abroad is firstly reviewed and analyzed from three aspects: gas path analysis and performance evaluation, mechanical fault diagnosis and information fusion. Then, the exciting key problems and challenges in the current research are pointed out. Finally, the future development trends are discussed.
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    Development of aircraft structural fatigue and structural integrity: Review
    CUI Degang, BAO Rui, ZHANG Rui, LIU Binchao, OUYANG Tian
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2021, 42 (5): 524394-524394.   DOI: 10.7527/S1000-6893.2020.24394
    Abstract2237)   HTML88)    PDF(pc) (9154KB)(852)       Save
    As the main factor affecting the safety of structures, the structural design and strength analysis of aircraft has developed from static strength design to safety-life design and damage-tolerance design, and further to the durability concept and aircraft structural integrity, during which the design and technique philosophies keep improving and undergo qualitative changes. However, the present understanding towards structural integrity in engineering practice is limited to the level of product development and testing, hindering its significance at a further level. This paper first introduces the development of aircraft structural design from static strength design to structural integrity design, the basic concept of aircraft structural integrity, and the main contents and key points of Aircraft Structural Integrity Program (ASIP). Moreover, the promotional transition from the traditional specification for analysis and testing within the design phase to the present one for process control and management within the whole product lifecycle is addressed by elucidating the "Five Tasks". Finally, two typical successful ASIP applications involving the design, verification and maintenance of aircraft structural integrity are presented as examples. Through the basic concepts and development of the main design philosophies, this paper shows the qualitative change of aircraft structural safety strategies from limited application within the design and development phase to thorough application for process control within the full lifecycle, and points out the trend that structural integrity philosophies are developing from experiment-based systematic approaches to digital ones.
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    Material⁃structure integrated design for high⁃performance aerospace thin⁃walled component
    Weihong ZHANG, Han ZHOU, Shaoying LI, Jihong ZHU, Lu ZHOU
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2023, 44 (9): 627428-627428.   DOI: 10.7527/S1000-6893.2022.27428
    Abstract2186)   HTML154)    PDF(pc) (4778KB)(1411)       Save

    The rapid development of the next generation of aerospace technology has imposed more and more stringent requirements for such structural performance as the ultra-strong load-bearing, extreme heat-proof, ultra-precision and ultra-lightweight. Therefore, how to design and fabricate high-performance, lightweight, and ultra-precise aerospace thin-walled structures has become a common concern in the field of advanced material and structural design and manufacturing. This paper reviews the main achievements of high-performance design and manufacture of thin-walled components and their aerospace applications in recent years, focusing on the scientific issues including the mapping law between multi-scale structures and structural performance, the composed manufacturing principle of multi-material and multi-scale structures, and the interaction mechanism between material organization evolution and structural deformation. Moreover, the manufacturing process constraints in structural optimization, the influence of additive manufacturing process parameters on the structural optimization, the material-structure integrated design method of high-performance structures and its application in aerospace structures are discussed. The development prospects and applications of the material-structure integrated design and manufacturing methods of typical aerospace thin-walled structures in the future are also prospected, which can provide references for future related research and aerospace applications.

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    A TDOA/FDOA cooperative localization method for multiple disjoint sources based on weighted multidimensional scaling analysis
    Ding WANG, Jiexin YIN, Xinguang ZHANG, Na’e ZHENG
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2023, 44 (7): 327105-327105.   DOI: 10.7527/S1000-6893.2022.27105
    Abstract2107)   HTML17)    PDF(pc) (4502KB)(523)       Save

    TDOA/FDOA localization is an important wireless positioning mechanism for moving emitters, and its location accuracy is greatly affected by measurement errors of TDOA/FDOA and prior measurement errors of sensor models (including sensor position and velocity). To improve the localization performance under the condition of high-level measurement errors, a TDOA/FDOA cooperative localization method for multiple disjoint sources is proposed based on weighted multidimensional scaling analysis in this paper. The proposed method consists of two calculation stages: Stage-a and Stage-b. Specifically, in Stage-a, two groups of scalar product matrices in multidimensional scaling analysis are employed to form the positioning relationship, which is further used to yield the solutions for the locations of multiple disjoint sources and sensors by constructing a weighting matrix. In Stage-b, a constrained minimization model is established based on the intermediate variables introduced in multidimensional scaling analysis to determine the estimation errors in Stage-a. By solving this optimization problem, the expression for the localization errors in Stage-a are obtained, so as to refine the position and velocity estimates of the multiple disjoint sources as well as the sensors. In addition, the first-order error analysis is employed to prove that the proposed method can asymptotically reach the Cramér-Rao Bound (CRB) accuracy. Simulation results show that the new method outperforms the existing TDOA/FDOA positioning methods.

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    Current status and prospect of overseas research on aeronautical fatigue
    SUN Xiasheng, SU Shaopu, SUN Hanbin, DONG Dengke
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2021, 42 (5): 524791-524791.   DOI: 10.7527/S1000-6893.2020.24791
    Abstract1990)   HTML102)    PDF(pc) (17003KB)(1509)       Save
    Fatigue is one of the key factors affecting the performance of aircraft in research or service. In this article, firstly, the aeronautical accidents caused by fatigue were quoted as clues to state the evolution of structural strength design concept and research situation at each specific period. Meanwhile, international aeronautical fatigue research and their significant development as well as the future developing directions in areas since 21 century has been reviewed and evaluated in the aspects of structural long-life design, fatigue analysis approaches and tools, full-scale structural fatigue testing technology, structural health monitoring and life extension of aging aircraft. Conclusively, considering the current problems and potential development directions, the challenges resisting the realization of high requirement on the long life, lightweight and high reliability of future aircraft design were pointed out on four topics:aeronautical fatigue on evaluation basic research, design and application research, testing evaluation and digital technology, which provides technical materials for the development of aeronautical fatigue.
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    Technical development of variable camber wing: Review
    WANG Binwen, YANG Yu, QIAN Zhansen, WANG Zhigang, LYU Shuaishuai, SUN Xiasheng
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2022, 43 (1): 24943-024943.   DOI: 10.7527/S1000-6893.2020.24943
    Abstract1958)   HTML119)    PDF(pc) (36682KB)(1497)       Save
    The Variable Camber Wing(VCW) remains a research hot-spot as it aims to ensure that aircraft acquire optimal aerodynamic efficiency in various flight conditions. The benefits brought by VCWs are firstly presented, and the demands of VCWs from different types of aircraft are classified and thoroughly described. The developing process of VCWs in the past decades are then reviewed in terms of the leading edge and the trailing edge, respectively, and the current major obstacles in application are listed. Further research directions are finally suggested.
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    Fundamental mechanical problems in high-performance aerospace composite structures: State-of-art review
    ZHAO Tian, LI Ying, ZHANG Chao, YAO Liaojun, HUANG Yixing, HUANG Zhixin, CHEN cheng, WANG Wandong, ZU Lei, ZHOU Huamin, QIU Jinhao, QIU Zhiping, FANG Daining
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2022, 43 (6): 526851-526851.   DOI: 10.7527/S1000-6893.2022.26851
    Abstract1836)   HTML105)    PDF(pc) (74835KB)(946)       Save
    Benefitting from the superiorities brought by the organic fusion of different materials, high-performance composites are considered as an effective approach to achieving light-weight design, multi-functionality and intelligentization of aviation aircraft. However, the high anisotropy and multi-scale structural properties of the composites also produce significant problems and challenges for structural design, fabrication and characterization. The application and development of high-performance composite materials in aircraft is a multi-disciplinary problem involving, material science, mechanical engineering and control technology. Focusing on several related fundamental mechanical problems, this paper mainly presents a critical review on the recent research progress in mechanical design and property evaluation, functional design and manufacturing mechanics of aircraft composite structures. An outlook for the research directions in aircraft composite structures is provided in the final part.
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    Parallel HVDC electric power system for more-electric-aircraft: State of the art and key technologies
    ZHANG Zhuoran, XU Yanwu, YU Li, LI Jincai, XIA Yiwen
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2021, 42 (6): 624069-624069.   DOI: 10.7527/S1000-6893.2020.24069
    Abstract1775)   HTML47)    PDF(pc) (17725KB)(940)       Save
    The integration of onboard secondary energy is gradually realized by the More Electric Aircraft (MEA), improving the efficiency, reliability, and safety of energy utilization. The High-Voltage DC (HVDC) power supply system with outstanding advantages such as lightweight, low loss, and high reliability can, in principle, realize easier parallel operation of the Electric Power System (EPS), enabling the expansion of the power supply capacity in a multi-engine/multi-generator layout, and hence uninterrupted power supply. In addition, both the electric power quality and reliability of the EPS are improved. The characteristics and advantages of the HVDC EPS are analyzed in this paper, followed by a summary of the research status and the key technical issues of the HVDC parallel EPS. A dual-channel HVDC parallel EPS based on novel doubly salient brushless DC generators is proposed and implemented to achieve current sharing control of the system, and the dynamic responses during sudden load changes, paralleling in, and splitting out are examined. The research has proved that the HVDC parallel EPS provides good steady-state accuracy and dynamic performance, exhibiting important value in the MEA or All Electric Aircraft (AEA) applications. The dynamic behaviors, the modeling method, and the protection logic of the HVDC parallel EPS still require further research.
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    Current status, challenges and opportunities of civil aero-engine diagnostics & health management Ⅰ: Diagnosis and prognosis of engine gas path, mechanical and FADEC
    CAO Ming, HUANG Jinquan, ZHOU Jian, CHEN Xuefeng, LU Feng, WEI Fang
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2022, 43 (9): 625573-625573.   DOI: 10.7527/S1000-6893.2021.25573
    Abstract1746)   HTML107)    PDF(pc) (7660KB)(1063)       Save
    The engineering advancements during the last two decades have presented opportunities as well as challenges for the Engine Health Management (EHM) system development of civil aero-engines. This R&D review provides an in-depth discussion on EHM needs, gaps and potential solutions/future R&D development directions, focusing on the "up-stream" EHM development modules: Engine gas path diagnostics and prognostics, mechanical diagnostics and prognostics, FADEC diagnostics and prognostics. Results shows the Unscented Kalman Filter (UKF) method and deep-learning neural networks have shown promises on improving the engine gas path diagnostics accuracy; composite fans have found widespread applications in turbo-fan engines; powder metallurgy has seen more and more applications on fabricating aero-engine parts with complex shapes; the accuracies of metal particle sensing technologies have witnessed significant improvements, with technology readiness level matching the aero-engine needs, and paved the way for fusion diagnostics with vibration signal. The result also show that electrification and intelligentization trends of FADEC system presents new challenges for the diagnostics of the traditionally centralized control architecture.
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    Review of distributed hybrid electric propulsion aircraft technology
    ZHU Bingjie, YANG Xixiang, ZONG Jian'an, DENG Xiaolong
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2022, 43 (7): 25556-025556.   DOI: 10.7527/S1000-6893.2021.25556
    Abstract1727)   HTML93)    PDF(pc) (14513KB)(1069)       Save
    Distributed hybrid electric propulsion system has great potential and advantage in development of general electric aviation. By the optimization of secondary power system, hybrid electric technology can not only heighten the utilization efficiency of energy, but also satisfied the distributed arrangement of power system for higher propulsive efficiency. The paper firstly summarized the current major types of electric aircraft, reviewed the history background of distributed electric propulsion aircraft. Then, the research status of distributed hybrid electric propulsion aircraft technology is summarized, this part mainly discussed the distributed layout technology of propulsion system, type-selection design of hybrid electric propulsion system, modeling and energy management of hybrid electric propulsion system, and so on. The key technologies of distributed hybrid electric propulsion at home and abroad are discussed fully. Eventually, combined with the research of the team, the difficult point problems and solutions of distributed hybrid electric propulsion aircraft are discussed in detail, including dynamic management strategy of energy based on complex system optimization control, optimal energy distribution prediction model driven by historical big data, and principle prototype designing of distributed hybrid electric propulsion system. The main content of this paper clarify the design thoughts and analysis method for distributed hybrid electric propulsion system and energy arrangement, which can provide references for the research of electric propulsion aircraft technology.
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    Intelligent air combat decision making and simulation based on deep reinforcement learning
    Pan ZHOU, Jiangtao HUANG, Sheng ZHANG, Gang LIU, Bowen SHU, Jigang TANG
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2023, 44 (4): 126731-126731.   DOI: 10.7527/S1000-6893.2022.26731
    Abstract1678)   HTML123)    PDF(pc) (4846KB)(1075)       Save

    Intelligent decision-making for aircraft air combat is a research hotspot of military powers in the world today. To solve the problem of Unmanned Aerial Vehicle (UAV) maneuvering decision-making in the close-range air combat game, an autonomous decision-making model based on deep reinforcement learning is proposed, where a reward function comprehensively considering the attack angle advantage, speed advantage, altitude advantage and distance advantage is adopted and improved. The improved reward function avoids the problem that the agent is induced to fall to the ground by the enemy aircraft, and can effectively guide the agent to converge to the optimal solution. Aiming at the problem of slow convergence caused by random sampling in reinforcement learning, we design a value-based prioritization method for experience pool samples. Under the premise of ensuring the algorithm convergence, the convergence speed of the algorithm is significantly accelerated. The decision-making model is verified based on the human-machine confrontation simulation platform, and the results show that the model can suppress the expert system and the driver in the process of close air combat.

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    Binary convolutional neural network: Review
    DING Wenrui, LIU Chunlei, LI Yue, ZHANG Baochang
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2021, 42 (6): 24504-024504.   DOI: 10.7527/S1000-6893.2020.24504
    Abstract1600)   HTML32)    PDF(pc) (6618KB)(409)       Save
    In recent years, Binary Convolutional Neural Networks (BNNs) have attracted much attention owing to their low storage and high computational efficiency. However, the mismatch between forward and backward quantization results in a huge performance gap between the BNN and the full-precision convolutional neural network, affecting the deployment of the BNN on resource-constrained platforms. Researchers have proposed a series of algorithms and training methods to reduce the performance gap during the binarization process, thereby promoting the application of BNNs to embedded portable devices. This paper makes a comprehensive review of BNNs, mainly from the perspectives of improving network representative capabilities and fully exploring the network training potential. Specifically, improving network representative capabilities includes the design of the binary quantization method and structure design, while fully exploring the network training potential involves loss function design and the training strategy. Finally, we discuss the performance of BNNs in different tasks and hardware platforms, and summarize the challenges in future research.
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    Knowledge graph construction technology and its application in aircraft power system fault diagnosis
    NIE Tongpan, ZENG Jiyan, CHENG Yujie, MA Liang
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2022, 43 (8): 625499-625499.   DOI: 10.7527/S1000-6893.2021.25499
    Abstract1493)   HTML65)    PDF(pc) (9686KB)(690)       Save
    The electrification degree of airborne equipment continues to increase with the development of science and technology. Owning to this, failure in aircraft power system is posing an increasing threat to flight safety, which granted necessity to fast and accurate health state assessment. The commonly used data-driven fault diagnosis method cannot make use of expert knowledge. Meanwhile, the result of data-driven method is lack of interpretability, and therefore, limits its application in real practice. Knowledge graph has the ability to normalize the storage of such unstructured data as expert knowledge and use it for diagnosis. Moreover, knowledge graph can utilize the unstructured knowledge and supply a reasonable explanation for the cause of the failure. However, in the field of fault diagnosis, there are still few studies on the application of knowledge graph technology. In this article, a knowledge graph construction and application technology for aircraft power system fault diagnosis is proposed. First, ontology of the knowledge graph, which specifies the entity and relation types in the knowledge graph, is constructed based on the priori expert knowledge. Then, Bi-Directional Long Short-Term Memory (Bi-LSTM) method is trained with BMEO-tagged corpus and utilized to extract entities from the unstructured texts. After that, an attention-based Bi-LSTM algorithm is trained with relation-tagged corpus and then utilized to realize relation extraction. Finally, the knowledge graph for aircraft power system fault diagnosis is constructed based on the extracted entities and relations. A fault isolation manual of aircraft power system is used as raw corpus data in the case study to verify the effectiveness of the proposed method by the indicators of precision and recall. Based on the knowledge graph, intelligent searching, recommending and Q & A are realized, which strongly support the application prospect of knowledge graph in the field of fault diagnosis.
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    Research progress and prospect of fatigue and structural integrity for aeronautical industry in China
    WANG Binwen, CHEN Xianmin, SU Yunlai, SUN Hanbin, YANG Yu, FAN Junling
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2021, 42 (5): 524651-524651.   DOI: 10.7527/S1000-6893.2020.24651
    Abstract1485)   HTML91)    PDF(pc) (27012KB)(1338)       Save
    In China, as the improvement of aeronautical industry, fatigue and structural integrity become one of the key problems that affect the life, safety and reliability of aircraft structures. After years of hard-working, aircraft design philosophy evolved gradually from static strength to safe-life, and now to fatigue and structural integrity as a guide. Aircraft structural integrity program has been implemented successfully into structural development for several new types. The service life, reliability and economy of the new generation aircraft structure have been improved significantly. However, with the improvement of aeronautical technology and the development requirements for new aircrafts, many new problems emerged in this area. From the perspective of aeronautical industry, this paper combs the progress and main achievements of aeronautical fatigue research in China, and focuses on the research status and engineering applications in the aspects of material/structure/process, analysis and evaluation method, fatigue test technology and service life management since 2000. Finally, some aeronautical fatigue research directions need to be focused on were proposed in order to provide reference for the further development of domestic aeronautical structures.
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    Real⁃time dense small object detection algorithm for UAV based on improved YOLOv5
    Zhiqiang FENG, Zhijun XIE, Zhengwei BAO, Kewei CHEN
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2023, 44 (7): 327106-327106.   DOI: 10.7527/S1000-6893.2022.27106
    Abstract1448)   HTML52)    PDF(pc) (5498KB)(414)       Save

    UAV aerial images have more complex backgrounds and a large number of dense small targets compared with natural scene images, which impose higher requirements on the detection network. On the premise of ensuring real-time object detection, a YOLOv5-based UAV real-time dense small object detection algorithm is proposed for the problem of low accuracy of dense small object detection in UAV view. First, combining Spatial Attention Module (SAM) with Channel Attention Module (CAM), the fully connected layer after feature compression in CAM is improved to reduce the computational effort. In addition, the connection structure of CAM and SAM is changed to improve the spatial dimensional feature capture capability. In summary, a Spatial-Channel Attention Module (SCAM) is proposed to improve the model's attention to the aggregated regions of small targets in the feature map; secondly, an SCAM- based Attentional Feature Fusion module (SC-AFF) is proposed to enhance the feature fusion efficiency of small targets by adaptively assigning attentional weights according to feature maps of different scales; finally, a backbone network is introduced in the Transformer in the backbone network, and use the SC-AFF to improve the feature fusion at the original residual connections to better capture global information and rich contextual information, and improve the feature extraction capability of dense small targets in complex backgrounds. Experiments are conducted on the VisDrone2021 dataset. The effects of different network scale parameters and different input resolutions on the detection accuracy and speed of YOLOv5 are first investigated. The analysis concludes that YOLOv5s is more suitable to be used as a benchmark model for UAV real-time object detection. Under the benchmark of YOLOv5s, the improved model improves mAP50 by 6.4% and mAP75 by 5.8%, and the FPS for high-resolution images can reach 46. The mAP50 of the model trained at an input resolution of 1504×1504 can reach 54.5%, which is 11.5% better than that of YOLOv4. The accuracy is improved while the detection speed FPS remains at 46, which is more suitable for real-time UAV object detection in dense small target scenarios.

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    Technical innovations of the Tianwen-1 Mission
    ZHANG Rongqiao, GENG Yan, SUN Zezhou, LI Dong, ZHONG Wenan, LI Haitao, CUI Xiaofeng, LIU Jianjun
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2022, 43 (3): 626689-626689.   DOI: 10.7527/S1000-6893.2021.26689
    Abstract1425)   HTML99)    PDF(pc) (2192KB)(930)       Save
    Tianwen-1 is the first mission in the world to achieve the three goals of Mars orbiting, landing and roving in one mission, and has made some key-technology breakthroughs. The mission objectives and flight progress are introduced, and eight kinds of innovation achievements and the main technical breakthroughs are comprehensively summarized in this paper. Specifically, the key technologies include the overall design of Mars orbiting, landing and roving objectives strongly coupled, multi-trajectory launch of Earth escape orbit, interplanetary flight and Mars capture, Mars enter, descent and landing, solutions adaptive to Martian harsh environment, 400-million-kilometer communication, advanced payloads of remote sensing and patrol detection, and Mars environmental modeling and ground validation. The complete success of the mission has made China become one of the advanced countries in the field of deep space exploration.
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    Current status, challenges and opportunities of civil aero-engine diagnostics & health management Ⅱ: Comprehensive off-board diagnosis, life management and intelligent condition based MRO
    CAO Ming, WANG Peng, ZUO Hongfu, ZENG Haijun, SUN Jianzhong, YANG Weidong, WEI Fang, CHEN Xuefeng
    ACTA AERONAUTICAET ASTRONAUTICA SINICA    2022, 43 (9): 625574-625574.   DOI: 10.7527/S1000-6893.2021.25574
    Abstract1339)   HTML135)    PDF(pc) (21809KB)(842)       Save
    Based on a comprehensive coverage of the civil aero-Engine Health Management (EHM) needs and goals, this research and development review first analyzes the current status quo & industry trends from the perspectives of the full blown Condition Based Maintenance Plus (CBM+) process, then addresses the challenges and gaps, and points out the critical paths for the future EHM research and development. Furthermore, this research and development review provides in-depth discussions on needs, gaps, and potential EHM solutions/future developments of the three "down-stream" EHM development modules: off-board comprehensive diagnostics, engine life management, intelligent condition based mro (maintenance, repair, overhaul).
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