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Resilient multi-objective mission planning for UAV formation:A unified framework integrating task pre-and re-assignment
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作者 Xinwei Wang Xiaohua Gao +4 位作者 Lei Wang Xichao Su Junhong Jin Xuanbo Liu Zhilong Deng 《Defence Technology(防务技术)》 2025年第3期203-226,共24页
Combat effectiveness of unmanned aerial vehicle(UAV)formations can be severely affected by the mission execution reliability.During the practical execution phase,there are inevitable risks where UAVs being destroyed o... Combat effectiveness of unmanned aerial vehicle(UAV)formations can be severely affected by the mission execution reliability.During the practical execution phase,there are inevitable risks where UAVs being destroyed or targets failed to be executed.To improve the mission reliability,a resilient mission planning framework integrates task pre-and re-assignment modules is developed in this paper.In the task pre-assignment phase,to guarantee the mission reliability,probability constraints regarding the minimum mission success rate are imposed to establish a multi-objective optimization model.And an improved genetic algorithm with the multi-population mechanism and specifically designed evolutionary operators is used for efficient solution.As in the task-reassignment phase,possible trigger events are first analyzed.A real-time contract net protocol-based algorithm is then proposed to address the corresponding emergency scenario.And the dual objective used in the former phase is adapted into a single objective to keep a consistent combat intention.Three cases of different scales demonstrate that the two modules cooperate well with each other.On the one hand,the pre-assignment module can generate high-reliability mission schedules as an elaborate mathematical model is introduced.On the other hand,the re-assignment module can efficiently respond to various emergencies and adjust the original schedule within a millisecond.The corresponding animation is accessible at bilibili.com/video/BV12t421w7EE for better illustration. 展开更多
关键词 Cooperative mission planning UAV formation mission reliability Evolutionary algorithm Contract net protocol
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A Plastic Surgery Mission: Personal Experience in Improving Outcomes
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作者 Mohamed Elsayed Mohamed Mohamed 《Modern Plastic Surgery》 2025年第1期32-43,共12页
Background: Missions organized by international societies and humanitarian organizations play a significant role in saving many patients’ lives and improving their quality of life, despite the surrounding frustrating... Background: Missions organized by international societies and humanitarian organizations play a significant role in saving many patients’ lives and improving their quality of life, despite the surrounding frustrating conditions. Methods: A team of plastic surgery volunteers was sent to Yemen by the KSHARC. Results: A successful mission was performed on 62 patients who underwent surgery, with more than 900 patients examined and receiving appropriate medications. Conclusion: Missions in disaster-affected areas are of great importance. The role of missions and humanitarian organizations should be empowered. 展开更多
关键词 missionS Humanitarian Organizations Plastic Surgery Natural Disasters Wars
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Experimental investigation and life prediction for the load spectrum with flight mission characteristics on a P/M superalloy
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作者 Renjie JIANG Xiaoguang YANG +2 位作者 Muwei CHENG Jia HUANG Duoqi SHI 《Chinese Journal of Aeronautics》 2025年第3期403-412,共10页
The service load on high temperature rotating components of aero-engines generally exhibits flight mission characteristics. The general shape of the load spectrum is that Type Ⅲ/Ⅳ cyclic loading and creep loading ar... The service load on high temperature rotating components of aero-engines generally exhibits flight mission characteristics. The general shape of the load spectrum is that Type Ⅲ/Ⅳ cyclic loading and creep loading are superimposed on Type Ⅰ cyclic loading. Meanwhile, the sequence of the Type Ⅲ/Ⅳ cyclic and creep loading varies with mission. This work performed load spectrum test with this characteristic on the Ni-based alloy FGH96. Then a life prediction method was developed based on the Chaboche fatigue damage accumulation model and a modified time fraction model. Creep followed by Fatigue (C-F) test was carried out to reveal the creep-fatigue interaction and calibrate parameters. The results show that most test results fall within the 2-fold deviation band. The sequence of creep-fatigue loading within the load spectrum exhibited a limited effect on life. Finally, simplified methods were developed to improve analysis efficiency, and cases where simplified methods could replace the proposed method were discussed. 展开更多
关键词 Load spectrum Life prediction Flight mission Loading sequence Niclel alloys
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“Becoming a family”—the effects of the hidden curriculum in transferring institutional mission:An experience from a century-old nursing school
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作者 Aimei Mao Hon-Lon Tam +1 位作者 Pak-Leng Cheong Iat-Kio Van 《International Journal of Nursing Sciences》 2025年第3期293-300,I0006,I0007,共10页
Objectives This study aimed to examine the role of the hidden curriculum in transmitting the educational mission and its impacts on nursing students’professional socialization.Methods This constructivist grounded the... Objectives This study aimed to examine the role of the hidden curriculum in transmitting the educational mission and its impacts on nursing students’professional socialization.Methods This constructivist grounded theory study involved twenty-six students and five faculty members from a century-old nursing school in Macao.Semi-structured interviews examined the factors influencing nursing students’choice of a specific nursing school and their general learning experiences in nursing studies.Open and focused coding was employed to develop categories and concepts that capture the nuances of how the hidden curriculum influences students’personal experiences,perceptions,and values related to developing their professional identities.The data analysis was guided by the“Community of Practice”model.Results The educational mission fostered a hidden curriculum that emphasized nurturing qualities and social responsibilities,creating a family-like learning environment that positively influenced the professional socialization of nursing students.Under the core theme of“becoming a family,”two sub-themes emerged:“student-peer interactions-fostering sisterly/brotherly learning partnerships”and“student-faculty interactions–faculty’s acting as parenting instructors.”While the hidden curriculum promoted a democratic and egalitarian learning atmosphere among student-peers,it simultaneously reinforced hierarchical power dynamics among senior-junior students and student-faculty relationships,mirroring the power-based interpersonal dynamics often found in traditional Chinese families.Conclusions Explicating the educational mission can help shape a hidden curriculum that benefits nursing students’professional socialization.Faculty members should reflect on the power inequalities reproduced by the hidden curriculum and establish appropriate boundaries in student-faculty relationships. 展开更多
关键词 Community of practice Educational mission Hidden curriculum Nurse students Professional socialization Qualitative study
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The Solar Close Observations and Proximity Experiments(SCOPE)mission
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作者 Jun Lin Jing Feng +31 位作者 Zhenhua Ge Jiang Tian Yuhao Chen Xin Cheng Hui Tian Jiansen He Alexei Pevtsov Haisheng Ji Shangbin Yang ParidaHashim Bin Zhou Yiteng Zhang Shenyi Zhang Xi Lu Yuan Yuan Liu Liu Haoyu Wang Hu Jiang Lei Deng Xingjian Shi Lin Ma Jingxing Wang Shanjie Huang Xiaoshi Zhang Hao Yang Zhonghua Yao He Zhang Yuanming Miao Lei Ni Zhixing Mei Jing Ye Yan Li 《Astronomical Techniques and Instruments》 2025年第3期148-174,共27页
The Solar Close Observations and Proximity Experiments(SCOPE)mission will send a spacecraft into the solar atmosphere at a low altitude of just 5 R☉from the solar center.It aims to elucidate the mechanisms behind sol... The Solar Close Observations and Proximity Experiments(SCOPE)mission will send a spacecraft into the solar atmosphere at a low altitude of just 5 R☉from the solar center.It aims to elucidate the mechanisms behind solar eruptions and coronal heating,and to directly measure the coronal magnetic field.The mission will perform in situ measurements of the current sheet between coronal mass ejections and their associated solar flares,and energetic particles produced by either reconnection or fast-mode shocks driven by coronal mass ejections.This will help to resolve the nature of reconnections in current sheets,and energetic particle acceleration regions.To investigate coronal heating,the mission will observe nano-flares on scales smaller than 70 km in the solar corona and regions smaller than 40 km in the photosphere,where magnetohydrodynamic waves originate.To study solar wind acceleration mechanisms,the mission will also track the process of ion charge-state freezing in the solar wind.A key achievement will be the observation of the coronal magnetic field at unprecedented proximity to the solar photosphere.The polar regions will also be observed at close range,and the inner edge of the solar system dust disk may be identified for the first time.This work presents the detailed background,science,and mission concept of SCOPE and discusses how we aim to address the questions mentioned above. 展开更多
关键词 Solar activities Coronal magnetic field In situ measurements Deep space mission Thermal protection system Thermal-electric conversion
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The KREEP-rich circum-Lalande region:A candidate landing area for future lunar crewed missions
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作者 Sheng Gou ZongYu Yue +9 位作者 YangTing Lin KaiChang Di YuYang He HengCi Tian Patrick CPinet ZhanChuan Cai Roberto Bugiolacchi HongLei Lin Sen Hu Wei Yang 《Earth and Planetary Physics》 2025年第6期1135-1146,共12页
The lunar magma ocean hypothesis suggests that the primordial KREEP(an acronym of potassium(K),rare earth element(REE),and phosphorus(P))was the final product of fractional crystallization.However,the primordial KREEP... The lunar magma ocean hypothesis suggests that the primordial KREEP(an acronym of potassium(K),rare earth element(REE),and phosphorus(P))was the final product of fractional crystallization.However,the primordial KREEP(a.k.a.urKREEP)has never been identified in previous lunar samples or meteorites.The Moon is the focus of many countries’and agencies’space exploration plans,and with the advancement of technology,crewed missions have been proposed.We propose two candidate landing sites,located respectively in the northwest(9.5°W,0.9°S)and southeast(11.1°W,6.2°S)of Lalande crater(8.6°W,4.5°S),for future crewed missions,with the primary goal of sampling the speculated urKREEP.Both sites are situated on the Th-(a critical marker of KREEP)and silica-rich Lalande ejecta in the Mare Insularum and Mare Nubium,respectively.Their geolocations at the low latitude on the lunar nearside,the flat surface,and the low rock abundance suggest the sites are safe for landing and meet the needs of real-time Earth-Moon communication.The astronauts could perform many extravehicular activities,such as collecting KREEP-rich samples,screening clast samples,and drilling regolith cores,to gather a variety of samples,such as Lalande ejecta,basalts,Copernicus ejecta,and regolith.The returned samples are valuable to explore the speculated urKREEP,to reveal the relationship between heat-producing elements and volcanism,to refine the lunar cratering chronology function,and to investigate volatiles in the regolith. 展开更多
关键词 primordial KREEP Th-rich Lalande ejecta landing sites lunar crewed missions extravehicular activities
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A Planning Method for Operational Test of UAV Swarm Based on Mission Reliability 被引量:2
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作者 Jingyu Wang Ping Jiang Jianjun Qi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1889-1918,共30页
The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV swarm.Due to the... The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV swarm.Due to the high cost and long duration of operational tests,it is essential to plan the test in advance.To solve the problem of planning UAV swarm operational test,this study considers the multi-stage feature of a UAV swarm mission,composed of launch,flight and combat stages,and proposes a method to find test plans that can maximize mission reliability.Therefore,a multi-stage mission reliability model for a UAV swarm is proposed to ensure successful implementation of the mission.A multi-objective integer optimization method that considers both mission reliability and cost is then formulated to obtain the optimal test plans.This study first constructs a mission reliability model for the UAV swarm in the combat stage.Then,the launch stage and flight stage are integrated to develop a complete PMS(Phased Mission Systems)reliability model.Finally,the Binary Decision Diagrams(BDD)and Multi Objective Quantum Particle Swarm Optimization(MOQPSO)methods are proposed to solve the model.The optimal plans considering both reliability and cost are obtained.The proposed model supports the planning of UAV swarm operational tests and represents a meaningful exploration of UAV swarm test planning. 展开更多
关键词 UAV swarm PMS MOQPSO BDD mission reliability operational test planning
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Strategic Study on the Development of Space Science in China and Proposals for Future Missions 被引量:2
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作者 WANG Chi SONG Tingting +1 位作者 LI Ming CAO Song 《空间科学学报》 CAS CSCD 北大核心 2024年第4期699-703,共5页
Since 2011,the Chinese Academy of Sciences(CAS)has implemented the Strategic Priority Program on Space Science(SPP).A series of scientific satellites have been developed and launched,such as Dark Matter Particle Explo... Since 2011,the Chinese Academy of Sciences(CAS)has implemented the Strategic Priority Program on Space Science(SPP).A series of scientific satellites have been developed and launched,such as Dark Matter Particle Explorer(DAMPE),Quantum Experiments at Space Scale(QUESS),Advanced Space-based Solar Observatory(ASO-S),Einstein Probe(EP),and significant scientific outcomes have been achieved.In order to plan the future space science missions in China,CAS has organized the Chinese space science community to conduct medium and long-term development strategy studies,and summarized the major scientific frontiers of space science as“One Black,Two Dark,Three Origins and Five Characterizations”.Five main scientific themes have been identified for China’s future breakthroughs,including the Extreme Universe,Space-Time Ripples,the Panoramic View of the Sun and Earth,the Habitable Planets,and Biological&Physical Science in Space.Space science satellite missions to be implemented before 2030 are proposed accordingly. 展开更多
关键词 Space science Space missions Space exploration
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Fast solution to the free return orbit's reachable domain of the manned lunar mission by deep neural network 被引量:2
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作者 YANG Luyi LI Haiyang +1 位作者 ZHANG Jin ZHU Yuehe 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期495-508,共14页
It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly eval... It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model. 展开更多
关键词 manned lunar mission free return orbit reachable domain(RD) deep neural network computation efficiency
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Life Origin in the Milky Way Galaxy: II. Scanning for Habitable Stellar Systems on Behalf of Future Space Missions
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作者 Alexander N. Safronov 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期681-692,共12页
The possibility of the life origin in the stellar systems, located at a distance of ~200 pc from the solar system, was investigated. The stars, in the spectrums of which C (carbon), O (oxygen), N (nitrogen), and P (ph... The possibility of the life origin in the stellar systems, located at a distance of ~200 pc from the solar system, was investigated. The stars, in the spectrums of which C (carbon), O (oxygen), N (nitrogen), and P (phosphorus) are found, are called DNA-stars. Based on stellar abundances a new method for searching for habitable exoplanets has been developed and a list of 48 DNA-stars in the solar neighborhood, on which life is possible, has been defined. The quota of DNA-stars is equal 1.3% of the total amount of Hypatia Stellar Catalog. Only three DNA-stars out of selected 48 stars belong to the spectral class as our Sun (G2V). The closest to the solar system is the DNA-star with the number HIP 15510, which belongs to the G8V class and is 6 pc away from the solar system. Nine DNA-stars, which have the highest chemical similarity with solar spectrum, were identified. It is identified that one of these nine stars, HIP 24681, has six planets. 展开更多
关键词 Interstellar mission Stellar Abundance HABITABILITY Hypatia Stellar Catalog DNA-Star
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“Einstein Probe”Mission Holds New Promise in Time-domain Astronomy
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作者 SONG Jianlan 《Bulletin of the Chinese Academy of Sciences》 2024年第1期8-10,共3页
Einstein Probe,an astronomical satellite designed for X-ray observation on astronomical events drastically evolving over time,was successfully sent into preset orbit by a Long March 2C rocket from China’s Xichang Sat... Einstein Probe,an astronomical satellite designed for X-ray observation on astronomical events drastically evolving over time,was successfully sent into preset orbit by a Long March 2C rocket from China’s Xichang Satellite Launch Center located in Sichuan Province at 15:03 GMT+8 on January 9,2024. 展开更多
关键词 PROBE PROMISE mission
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Key networks to create disaster resilient Smart Cities Mission: A case for remodeling India’s Smart Cities Mission to include disaster resilience
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作者 Yamini Meduri R.Singh Geetha Manoharan 《Resilient Cities and Structures》 2024年第4期52-62,共11页
Amidst a concerning surge in urban losses attributed to disasters,this research paper explores the intricate relationship between urban development,disaster mitigation,and resilience emphasizing the significance of ad... Amidst a concerning surge in urban losses attributed to disasters,this research paper explores the intricate relationship between urban development,disaster mitigation,and resilience emphasizing the significance of addressing disaster vulnerability in urban settings,where a substantial portion of the population faces risks stemming from high population density,limited resilience,and inadequate coping capabilities.The study advocates for the integration of disaster resilience principles into the Smart Cities Mission of India,placing particular emphasis on the necessity of developing infrastructure,establishing early warning systems,and fostering community engagement to bolster urban resilience.Furthermore,the paper draws comparisons and parallels between the components of smart cities,mitigation strategies,and disaster resilience,illuminating their interconnectedness and potential synergies.In conclusion,the study recommends the incorporation of essential network elements to establish a Smart Cities Mission that is resilient to disasters,ultimately aiming to safeguard urban communities from the adverse impacts of future calamities. 展开更多
关键词 Disaster resilience Smart city mission Disaster mitigation Disaster management
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A Study on Advertisements in The Chinese Recorder and Missionary Journal
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作者 WANG Hai WU Zong-yang 《Journal of Literature and Art Studies》 2021年第5期360-367,共8页
The Chinese Recorder and Missionary Journal is one of the most valued English literature in China’s history of Christianity and the key publications of missionaries from the second half of the 19th Century to the fir... The Chinese Recorder and Missionary Journal is one of the most valued English literature in China’s history of Christianity and the key publications of missionaries from the second half of the 19th Century to the first half of the 20th Century.The advertisements in it have not been properly stressed by the academic world,most of which are even deleted in the bound volumes.This paper aims to give a preliminary study on the advertisements in Chinese Recorder and Missionary Journal,comparing and analyzing advertisers,slogans and text structures and appeal methods of advertisements of shipping,banking,schools and book introduction in Chinese Recorder and Missionary Journal,thus demonstrating its significance in China’s modern advertising industry and Sino-western commercial trade and cultural exchange. 展开更多
关键词 Chinese Recorder and missionary Journal protestant missionaries in China mission press SECULARIZATION study on Advertisements in The Chinese Recorder and missionary Journal
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Mission segment division of the whole aeroengine loading spectrum based on flight actions 被引量:1
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作者 Yu JIN Zhigang SUN +3 位作者 Yingdong SONG Xin LIN Xuming NIU Junjie DING 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第2期164-174,共11页
This paper studies on a division method of the whole aeroengine loading spectrum flight mission segment and rotor speed mission segment,which is based on the actual flight actions and related to the flight operations ... This paper studies on a division method of the whole aeroengine loading spectrum flight mission segment and rotor speed mission segment,which is based on the actual flight actions and related to the flight operations of aeroengine and is suitable for the variable-speed aeroengines such as turbojet and turbofan.Through the research,the aeroengine loading spectrum operation-related mission segments can be divided,which can provide important data basis for the life research on the structures which are sensitive to flight maneuver(such as the main shaft,large gearbox and installation section),lay a foundation for the simulation,compilation and prediction of the whole aeroengine loading spectrum.Firstly,based on the summary of basic flight actions in actual flight,the division of flight mission segment was realized by programming.Moreover,the aeroengine rotor speed mission segments,associated with flight actions and missions,were divided based on the flight mission segment division results.Besides,the efficiency and accuracy of the mission segment division results were verified by adopting measured loading spectrum data.Finally,the characteristics of speed mission segment division results were compared and analyzed in tables and figures.The comparison results show that the characteristics of similar speed mission segments are similar,while the characteristics of different speed mission segments are different.And the shapes of similar mission segments vary to the change of flight actions and operations,which can reflect the operation-related feature of the segments. 展开更多
关键词 Aircraft engine Flight mission segment mission segment division Rotor speed mission segment Spectrum analysis
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AC-PSO ALGORITHM FOR UAV MISSION PLANNING 被引量:2
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作者 谭皓 李玉峰 +2 位作者 王金岩 何亦征 沈春林 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第3期264-270,共7页
Choosing the best path during unmanned air vehicle (UAV) flying is the target of the UAV mission planning problem. Because of its nearly constant flight height, the UAV mission planning problem can be treated as a 2... Choosing the best path during unmanned air vehicle (UAV) flying is the target of the UAV mission planning problem. Because of its nearly constant flight height, the UAV mission planning problem can be treated as a 2-D (horizontal) path arrangement problem. By modeling the antiaircraft threat, the UAV mission planning can be mapped to the traveling seaman problem (TSP). A new algorithm is presented to solve the TSP. The algorithm combines the traditional ant colony system (ACS) with particle swarm optimization (PSO), thus being called the AC-PSO algorithm. It uses one by one tour building strategy like ACS to determine that the target point can be chosen like PSO. Experiments show that AC-PSO synthesizes both ACS and PSO and obtains excellent solution of the UAV mission planning with a higher accuracy. 展开更多
关键词 unmanned air vehicle mission planning particle swarm optimization evolutionary computation
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Modeling for UAV resource scheduling under mission synchronization 被引量:3
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作者 Jia Zeng Xiaoke Yang +1 位作者 Lingyu Yang Gongzhang Shen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第5期821-826,共6页
Unmanned aerial vehicle(UAV) resource scheduling means to allocate and aggregate the available UAV resources depending on the mission requirements and the battlefield situation assessment.In previous studies,the mod... Unmanned aerial vehicle(UAV) resource scheduling means to allocate and aggregate the available UAV resources depending on the mission requirements and the battlefield situation assessment.In previous studies,the models cannot reflect the mission synchronization;the targets are treated respectively,which results in the large scale of the problem and high computational complexity.To overcome these disadvantages,a model for UAV resource scheduling under mission synchronization is proposed,which is based on single-objective non-linear integer programming.And several cooperative teams are aggregated for the target clusters from the available resources.The evaluation indices of weapon allocation are referenced in establishing the objective function and the constraints for the issue.The scales of the target clusters are considered as the constraints for the scales of the cooperative teams to make them match in scale.The functions of the intersection between the "mission time-window" and the UAV "arrival time-window" are introduced into the objective function and the constraints in order to describe the mission synchronization effectively.The results demonstrate that the proposed expanded model can meet the requirement of mission synchronization,guide the aggregation of cooperative teams for the target clusters and control the scale of the problem effectively. 展开更多
关键词 unmanned aerial vehicle(UAV) mission planning resource scheduling mission synchronization time-window integer programming target cluster.
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Scheme design of the CHANG'E-5T1 extended mission 被引量:3
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作者 Lei LIU Chunyang HU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第7期1559-1567,共9页
Flight schemes for the CHANG'E-5T1 extended mission are investigated in this paper.In the flight scheme and trajectory design, the remaining propellant of the CHANG'E-5T1 mission is utilized. The CHANG'E-5T1 missio... Flight schemes for the CHANG'E-5T1 extended mission are investigated in this paper.In the flight scheme and trajectory design, the remaining propellant of the CHANG'E-5T1 mission is utilized. The CHANG'E-5T1 mission is firstly introduced with feasible flight goals derived based on the terminal trajectory and satellite status. The flight schemes are designed to include a lunar return and the libration points in the Sun-Earth/Moon and Earth-Moon systems, with an emphasis on the Earth-Moon triangle libration point thus far unexplored. Secondly, three schemes are proposed for the CHANG'E-5T1 extended mission with different flight goals. The direct libration point orbit transfer and injection method is adopted to solve the issue in the transfer trajectory design.Furthermore, an innovative concept is proposed to transfer from the Earth-Moon collinear libration point to the triangle point using the Sun-Earth/Moon libration point. Finally, the merits and drawbacks of the three schemes are discussed in terms of flight time, control energy and frequency, flight distance, and goal value. As a result, the scheme including a lunar return and the Earth-Moon L2 libration point is selected for the CHANG'E-5T1 extended mission. A flight to the Earth-Moon libration point is achieved, replicating the achievement of the ARTEMIS mission. 展开更多
关键词 CHANG'E-5T1 mission Extended mission Flight scheme Libration point Lunar exploration Trajectory design
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Entropy based inverse design of aircraft mission success space in system-of-systems confrontation 被引量:3
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作者 Yuan GAO Yongliang TIAN +1 位作者 Hu LIU Jianwen HU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第12期99-109,共11页
This paper presents a practical and efficient design method for aircraft Mission Success Space(MSS)based on the entropy measurement(EM).First,fundamentals regarding MSS,Inverse Design(ID)and entropy are discussed.Then... This paper presents a practical and efficient design method for aircraft Mission Success Space(MSS)based on the entropy measurement(EM).First,fundamentals regarding MSS,Inverse Design(ID)and entropy are discussed.Then,two EM schemes of entropy-based ID and the whole MSS ID procedure are given to demonstrate alternative ways of entropy quantification and MSS design.After that,Genetic Algorithm(GA)is utilized as a search algorithm to find the optimal MSS design with the minimum objective,entropy,in each EM scheme.A simulation case of aircraft penetration mission is given for the method validation where the best aircraft MSS design is obtained by GA according to the minimum entropy.Results from two schemes are compared at the end. 展开更多
关键词 Effectiveness evaluation ENTROPY Inverse design Military missions mission success space System of systems(SoS)
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Cutting-Edge Space Exploration Technology Maturity Level Facilitation with Support of Space Debris Removal Missions 被引量:2
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作者 Hamed Ahmadloo Jingrui Zhang 《Journal of Beijing Institute of Technology》 EI CAS 2018年第4期477-484,共8页
Considering current space debris situation in outer space environment,different methods for debris removal missions are proposed.In addition,advanced technologies are needed to be demonstrated for future human space e... Considering current space debris situation in outer space environment,different methods for debris removal missions are proposed.In addition,advanced technologies are needed to be demonstrated for future human space exploration programs.The main issue regarding to these missions is high mission cost for both debris removal missions and space environmental tests to achieve high maturity level for new space-usable technologies.Since,these missions are unavoidable for future of human space activities,a solution which can tackle these challenges is necessary.This paper will address to an idea which has the possibility to give a solution for facilitating technology readiness level(TRL)maturity tests by debris removal mission platform consideration. 展开更多
关键词 space debris removal missions technology demonstrator missions technology readiness level drag augmentation methods
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Global Mission Sensitivity Study for Phased MissionSystem with Analysis of Variance Method 被引量:1
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作者 吴昕阳 武小悦 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期809-811,共3页
A comprehensive mission sensitivity analysis index based on Sobol's index called global mission sensitivity( GMS) was proposed in this paper which focused on analyzing the mission sensitivity of components of phas... A comprehensive mission sensitivity analysis index based on Sobol's index called global mission sensitivity( GMS) was proposed in this paper which focused on analyzing the mission sensitivity of components of phased mission systems( PMS). The simulation strategy of GMS based on a Petri net and Monte Carlo method was presented which had broad applicability. Finally,the GMS and Birnbaum's sensitivity of components in a PMS example were compared. The GMS of component is demonstrated to be more adaptable to reflect the component mission sensitivity when the rated reliability parameters of components cannot be obtained, and components have state dependency or the system is subjected to common cause failure. 展开更多
关键词 phased mission system(PMS) global mission sensitivity(GMS) Sobol’s index
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