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A novel framework to intercept GPS-denied,bomb-carrying,nonmilitary,kamikaze drones:Towards protecting critical infrastructures
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作者 Athanasios N.Skraparlis Klimis S.Ntalianis Nicolas Tsapatsoulis 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期225-241,共17页
Protection of urban critical infrastructures(CIs)from GPS-denied,bomb-carrying kamikaze drones(G-BKDs)is very challenging.Previous approaches based on drone jamming,spoofing,communication interruption and hijacking ca... Protection of urban critical infrastructures(CIs)from GPS-denied,bomb-carrying kamikaze drones(G-BKDs)is very challenging.Previous approaches based on drone jamming,spoofing,communication interruption and hijacking cannot be applied in the case under examination,since G-B-KDs are uncontrolled.On the other hand,drone capturing schemes and electromagnetic pulse(EMP)weapons seem to be effective.However,again,existing approaches present various limitations,while most of them do not examine the case of G-B-KDs.This paper,focuses on the aforementioned under-researched field,where the G-B-KD is confronted by two defensive drones.The first neutralizes and captures the kamikaze drone,while the second captures the bomb.Both defensive drones are equipped with a net-gun and an innovative algorithm,which,among others,estimates the locations of interception,using a real-world trajectory model.Additionally,one of the defensive drones is also equipped with an EMP weapon to damage the electronics equipment of the kamikaze drone and reduce the capturing time and the overall risk.Extensive simulated experiments and comparisons to state-of-art methods,reveal the advantages and limitations of the proposed approach.More specifically,compared to state-of-art,the proposed approach improves:(a)time to neutralize the target by at least 6.89%,(b)maximum number of missions by at least 1.27%and(c)total cost by at least 5.15%. 展开更多
关键词 Critical infrastructure Kamikaze drone GPS-Denied Bomb-carrying Trajectory estimation
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A Software-in-the-Loop Implementation of Adaptive Formation Control for Fixed-Wing UAVs 被引量:5
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作者 Jun Yang Ximan Wang +2 位作者 Simone Baldi Satish Singh Stefano Fari 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第5期1230-1239,共10页
This paper discusses the design and software-in-theloop implementation of adaptive formation controllers for fixedwing unmanned aerial vehicles(UAVs) with parametric uncertainty in their structure, namely uncertain ma... This paper discusses the design and software-in-theloop implementation of adaptive formation controllers for fixedwing unmanned aerial vehicles(UAVs) with parametric uncertainty in their structure, namely uncertain mass and inertia. In fact, when aiming at autonomous flight, such parameters cannot assumed to be known as they might vary during the mission(e.g.depending on the payload). Modeling and autopilot design for such autonomous fixed-wing UAVs are presented. The modeling is implemented in Matlab, while the autopilot is based on ArduPilot, a popular open-source autopilot suite. Specifically, the ArduP ilot functionalities are emulated in Matlab according to the Ardupilot documentation and code, which allows us to perform software-in-the-loop simulations of teams of UAVs embedded with actual autopilot protocols. An overview of realtime path planning, trajectory tracking and formation control resulting from the proposed platform is given. The software-inthe-loop simulations show the capability of achieving different UAV formations while handling uncertain mass and inertia. 展开更多
关键词 ArduPilot ADAPTIVE formation control fixed-wing UAVs software-in-the-loop simulations
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Path planning for moving target tracking by fixed-wing UAV 被引量:6
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作者 Song-lin Liao Rong-ming Zhu +3 位作者 Nai-qi Wu Tauqeer Ahmed Shaikh Mohamed Sharaf Almetwally M.Mostafa 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第4期811-824,共14页
For the automatic tracking of unknown moving targets on the ground,most of the commonly used methods involve circling above the target.With such a tracking mode,there is a moving laser spot on the target,which will br... For the automatic tracking of unknown moving targets on the ground,most of the commonly used methods involve circling above the target.With such a tracking mode,there is a moving laser spot on the target,which will bring trouble for cooperative manned helicopters.In this paper,we propose a new way of tracking,where an unmanned aerial vehicle(UAV) circles on one side of the tracked target.A circular path algorithm is developed for monitoring the relative position between the UAV and the target considering the real-time range and the bearing angle.This can determine the center of the new circular path if the predicted range between the UAV and the target does not meet the monitoring requirements.A transition path algorithm is presented for planning the transition path between circular paths that constrain the turning radius of the UAV.The transition path algorithm can generate waypoints that meet the flight ability.In this paper,we analyze the entire method and detail the scope of applications.We formulate an observation angle as an evaluation index.A series of simulations and evaluation index comparisons verify the effectiveness of the proposed algorithms. 展开更多
关键词 Bearing angle fixed-wing UAV Laser designation Moving target tracking Path planning
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Dynamic collision avoidance for cooperative fixed-wing UAV swarm based on normalized artificial potential field optimization 被引量:6
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作者 LIU Wei-heng ZHENG Xin DENG Zhi-hong 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第10期3159-3172,共14页
Cooperative path planning is an important area in fixed-wing UAV swarm.However,avoiding multiple timevarying obstacles and avoiding local optimum are two challenges for existing approaches in a dynamic environment.Fir... Cooperative path planning is an important area in fixed-wing UAV swarm.However,avoiding multiple timevarying obstacles and avoiding local optimum are two challenges for existing approaches in a dynamic environment.Firstly,a normalized artificial potential field optimization is proposed by reconstructing a novel function with anisotropy in each dimension,which can make the flight speed of a fixed UAV swarm independent of the repulsive/attractive gain coefficient and avoid trapping into local optimization and local oscillation.Then,taking into account minimum velocity and turning angular velocity of fixed-wing UAV swarm,a strategy of decomposing target vector to avoid moving obstacles and pop-up threats is proposed.Finally,several simulations are carried out to illustrate superiority and effectiveness. 展开更多
关键词 fixed-wing UAV swarm cooperative path planning normalized artificial potential field dynamic obstacle avoidance local optimization
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Detection and Classification on Amateur Drones Based on Cepstrum of Radio Frequency Signal 被引量:4
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作者 GUAN Xiangmin MA Jianxiang ZHANG Weidong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第4期597-606,共10页
As a prospective component of the future air transportation system,unmanned aerial vehicles(UAVs)have attracted enormous interest in both academia and industry.However,small UAVs are barely supervised in the current s... As a prospective component of the future air transportation system,unmanned aerial vehicles(UAVs)have attracted enormous interest in both academia and industry.However,small UAVs are barely supervised in the current situation.Crash accidents or illegal airspace invading caused by these small drones affect public security negatively.To solve this security problem,we use the back-propagation neural network(BPNN),the support-vector machine(SVM),and the k-nearest neighbors(KNN)method to detect and classify the non-cooperative drones at the edge of the flight restriction zone based on the cepstrum of the radio frequency(RF)signal of the drone’s downlink.The signal from five various amateur drones and ambient wireless devices are sampled in an electromagnetic clean environment.The detection and classification algorithm based on the cepstrum properties is conducted.Results of the outdoor experiments suggest the proposed workflow and methods are sufficient to detect non-cooperative drones with an average accuracy of around 90%.The mainstream downlink protocols of amateur drones can be classified effectively as well. 展开更多
关键词 drone detection radio frequency signal CEPSTRUM machine learning
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The Use of Drones in Forestry 被引量:4
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作者 Tiberiu Paul Banu Gheorghe Florian Borlea Constantin Banu 《Journal of Environmental Science and Engineering(B)》 2016年第11期557-562,共6页
Recently, drones have found applicability in a variety of study fields, one of these being forestry, where an increasing interest is given to this segment of technology, especially due to the high-resolution data that... Recently, drones have found applicability in a variety of study fields, one of these being forestry, where an increasing interest is given to this segment of technology, especially due to the high-resolution data that can be collected flexibly in a short time and at a relatively low price. Also, drones have an important role in filling the gaps of common data collected using manned aircraft or satellite remote sensing, while having many advantages both in research and in various practical applications particularly in forestry as well as in land use in general. This paper aims to briefly describe the different approaches of applications of UAVs (Unmanned Aircraft Vehicles) in forestry, such as forest mapping, forest management planning, canopy height model creation or mapping forest gaps. These approaches have great potential in the near future applications and their quick implementation in a variety of situations is desirable for the sustainable management of forests. 展开更多
关键词 drones UAV remote sensing forest management.
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A mobility compensation method for drones in SG-eloT 被引量:2
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作者 Liguo Weng Yanghui Zhang +2 位作者 Yong Yang Min Fang Zelong Yu 《Digital Communications and Networks》 SCIE CSCD 2021年第2期196-200,共5页
In order to achieve the specific goal of a smart grid,the concept of electricity Internet of Things(eloT)has been proposed to assist the monitoring and inspection of power transmission line state and optimize the asse... In order to achieve the specific goal of a smart grid,the concept of electricity Internet of Things(eloT)has been proposed to assist the monitoring and inspection of power transmission line state and optimize the asset utilization.The long power transmission line and the complex field operation environment urge the introduction of drones into the eloT for fast power transmission line inspection,data collection from sensors for further big data analysis,adaptive control of power line voltage,etc.Additionally,drones can also act as a central communication control or relay point to serve the data exchange among sensors,drones and power transmission line maintenance personnel in the scenario where the conventional mobile communication service is not available.However,the fast mobility of drones may affect the signal transmission and position estimation performance,which may further deteriorate the networking performance.In order to solve this problem,a mobility compensation method is proposed,which includes the steps of frequency offset estimation and relative velocity calculation.Through the Monte Carlo simulations,the proposed algorithm shows favorable gains compared with the conventional ones. 展开更多
关键词 SG-eloT drones MOBILITY Frequency offset compensation
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A Drones Optimal Path Planning Based on Swarm Intelligence Algorithms 被引量:1
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作者 Mahmoud Ragab Ali Altalbe +2 位作者 Abdullah Saad Al-Malaise ALGhamdi SAbdel-khalek Rashid A.Saeed 《Computers, Materials & Continua》 SCIE EI 2022年第7期365-380,共16页
The smart city comprises various interlinked elements which communicate data and offers urban life to citizen.Unmanned Aerial Vehicles(UAV)or drones were commonly employed in different application areas like agricultu... The smart city comprises various interlinked elements which communicate data and offers urban life to citizen.Unmanned Aerial Vehicles(UAV)or drones were commonly employed in different application areas like agriculture,logistics,and surveillance.For improving the drone flying safety and quality of services,a significant solution is for designing the Internet of Drones(IoD)where the drones are utilized to gather data and people communicate to the drones of a specific flying region using the mobile devices is for constructing the Internet-of-Drones,where the drones were utilized for collecting the data,and communicate with others.In addition,the SIRSS-CIoD technique derives a tuna swarm algorithm-based clustering(TSA-C)technique to choose cluster heads(CHs)and organize clusters in IoV networks.Besides,the SIRSS-CIoD technique involves the design of a biogeography-based optimization(BBO)technique to an optimum route selection(RS)process.The design of clustering and routing techniques for IoD networks in smart cities shows the novelty of the study.A wide range of experimental analyses is carried out and the comparative study highlighted the improved performance of the SIRSS-CIoD technique over the other approaches. 展开更多
关键词 drones smart city swarm intelligence route selection internet of drones NETWORKING
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DroneRFa:用于侦测低空无人机的大规模无人机射频信号数据集 被引量:3
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作者 俞宁宁 毛盛健 +3 位作者 周成伟 孙国威 史治国 陈积明 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第4期1147-1156,共10页
为研究与发展反无人机检测识别技术,该文公开了一个名为DroneRFa的大规模无人机射频信号数据集。该数据集使用软件无线电设备探测无人机与遥控器相互通信的射频信号,包含城市户外场景下运动无人机信号9类、城市室内场景下信号15类以及... 为研究与发展反无人机检测识别技术,该文公开了一个名为DroneRFa的大规模无人机射频信号数据集。该数据集使用软件无线电设备探测无人机与遥控器相互通信的射频信号,包含城市户外场景下运动无人机信号9类、城市室内场景下信号15类以及背景参照信号1类。每类数据有不少于12个片段,每个片段包含1亿个以上的采样点。数据采集覆盖了3个ISM无线电频段,记录无人机多频通信的真实活动。该数据集具有详细的无人机户外飞行距离和工作频段标注,以前缀字符结合二进制编码的形式方便用户灵活访问所需数据。此外,该文提供了基于频谱可视统计特征和基于深度学习表征的两种无人机识别方案,以验证数据集的可靠和有效性。 展开更多
关键词 人工智能 反无人机检测 频谱学习 信号识别
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Two-layer formation-containment fault-tolerant control of fixed-wing UAV swarm for dynamic target tracking 被引量:2
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作者 QIN Boyu ZHANG Dong +1 位作者 TANG Shuo XU Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1375-1396,共22页
This paper tackles the formation-containment control problem of fixed-wing unmanned aerial vehicle(UAV)swarm with model uncertainties for dynamic target tracking in three-dimensional space in the faulty case of UAVs’... This paper tackles the formation-containment control problem of fixed-wing unmanned aerial vehicle(UAV)swarm with model uncertainties for dynamic target tracking in three-dimensional space in the faulty case of UAVs’actuator and sensor.The fixed-wing UAV swarm under consideration is organized as a“multi-leader-multi-follower”structure,in which only several leaders can obtain the dynamic target information while others only receive the neighbors’information through the communication network.To simultaneously realize the formation,containment,and dynamic target tracking,a two-layer control framework is adopted to decouple the problem into two subproblems:reference trajectory generation and trajectory tracking.In the upper layer,a distributed finite-time estimator(DFTE)is proposed to generate each UAV’s reference trajectory in accordance with the control objective.Subsequently,a distributed composite robust fault-tolerant trajectory tracking controller is developed in the lower layer,where a novel adaptive extended super-twisting(AESTW)algorithm with a finite-time extended state observer(FTESO)is involved in solving the robust trajectory tracking control problem under model uncertainties,actuator,and sensor faults.The proposed controller simultaneously guarantees rapidness and enhances the system’s robustness with fewer chattering effects.Finally,corresponding simulations are carried out to demonstrate the effectiveness and competitiveness of the proposed two-layer fault-tolerant cooperative control scheme. 展开更多
关键词 fixed-wing unmanned aerial vehicle(UAV)swarm two-layer control formation-containment dynamic target tracking
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Classification of birds and drones by exploiting periodical motions in Doppler spectrum series 被引量:1
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作者 DUAN Jia ZHANG Lei +3 位作者 WU Yifeng ZHANG Yue ZHAO Zeya GUO Xinrong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期19-27,共9页
With the rapidly growing abuse of drones, monitoring and classification of birds and drones have become a crucial safety issue. With similar low radar cross sections(RCSs), velocities, and heights, drones are usually ... With the rapidly growing abuse of drones, monitoring and classification of birds and drones have become a crucial safety issue. With similar low radar cross sections(RCSs), velocities, and heights, drones are usually difficult to be distinguished from birds in radar measurements. In this paper, we propose to exploit different periodical motions of birds and drones from highresolution Doppler spectrum sequences(DSSs) for classification.This paper presents an elaborate feature vector representing the periodic fluctuations of RCS and micro kinematics. Fed by the Doppler spectrum and feature sequence, the long to short-time memory(LSTM) is used to solve the time series classification.Different classification schemes to exploit the Doppler spectrum series are validated and compared by extensive real-data experiments, which confirms the effectiveness and superiorities of the proposed algorithm. 展开更多
关键词 target classification long-to-short memory(LSTM) drone discrimination Doppler spectrum series
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Radio Controlled “3D Aerobatic Airplanes” as Basis for Fixed-Wing UAVs with VTOL Capability 被引量:1
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作者 Chung-How Poh Chung-Kiak Poh 《Open Journal of Applied Sciences》 2014年第12期515-521,共7页
There are fundamental performance compromises between rotary-wing and fixed-wing UAVs. The general solution to address this well-known problem is the design of a platform with some degree of reconfigurable airframes. ... There are fundamental performance compromises between rotary-wing and fixed-wing UAVs. The general solution to address this well-known problem is the design of a platform with some degree of reconfigurable airframes. For critical missions (civilian or military), it is imperative that mechanical complexity is kept to a minimum to help achieve mission success. This work proposes that the tried-and-true radio controlled (RC) aerobatic airplanes can be implemented as basis for fixed-wing UAVs having both speed and vertical takeoff and landing (VTOL) capabilities. These powerful and highly maneuverable airplanes have non-rotatable nacelles, yet capable of deep stall maneuvers. The power requirements for VTOL and level flight of an aerobatic RC airplane are evaluated and they are compared to those of a RC helicopter of similar flying weight. This work provides quantitative validation that commercially available RC aerobatic airplanes can serve as platform to build VTOL capable fixed-wing UAVs that are agile, cost effective, reliable and easy maintenance. 展开更多
关键词 Aerobatics Unmanned AERIAL Vehicle fixed-wing VTOL HOVER
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Loader and Tester Swarming Drones for Cellular PhoneNetwork Loading and Field Test: Non-stochasticParticle Swarm Optimization 被引量:1
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作者 Amir Mirzaeinia Mostafa Hassanalian +1 位作者 Mohammad Shekaramiz Mehdi Mirzaeinia 《Journal of Autonomous Intelligence》 2019年第2期14-24,共11页
Cellular network operators have problems to test their network without affecting their user experience. Testingnetwork performance in a loaded situation is a challenge for the network operator because network performa... Cellular network operators have problems to test their network without affecting their user experience. Testingnetwork performance in a loaded situation is a challenge for the network operator because network performance differswhen it has more load on the radio access part. Therefore, in this paper, deploying swarming drones is proposed to loadthe cellular network and scan/test the network performance more realistically. Besides, manual swarming dronenavigation is not efficient enough to detect problematic regions. Hence, particle swarm optimization is proposed to bedeployed on swarming drone to find the regions where there are performance issues. Swarming drone communicationshelps to deploy the particle swarm optimization (PSO) method on them. Loading and testing swarm separation help tohave almost non-stochastic received signal level as an objective function. Moreover, there are some situations that morethan one network parameter should be used to find a problematic region in the cellular network. It is also proposed toapply multi-objective PSO to find more multi-parameter network optimization at the same time. 展开更多
关键词 Particle Swarm OPTIMIZATION SWARMING drone Cellular NETWORK Radio OPTIMIZATION Loaded NETWORK Test
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Intelligent Optimization-Based Clustering with Encryption Technique for Internet of Drones Environment
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作者 Dalia H.Elkamchouchi Jaber S.Alzahrani +5 位作者 Hany Mahgoub Amal S.Mehanna Anwer Mustafa Hilal Abdelwahed Motwakel Abu Sarwar Zamani Ishfaq Yaseen 《Computers, Materials & Continua》 SCIE EI 2022年第12期6617-6634,共18页
The recent technological developments have revolutionized the functioning of Wireless Sensor Network(WSN)-based industries with the development of Internet of Things(IoT).Internet of Drones(IoD)is a division under IoT... The recent technological developments have revolutionized the functioning of Wireless Sensor Network(WSN)-based industries with the development of Internet of Things(IoT).Internet of Drones(IoD)is a division under IoT and is utilized for communication amongst drones.While drones are naturally mobile,it undergoes frequent topological changes.Such alterations in the topology cause route election,stability,and scalability problems in IoD.Encryption is considered as an effective method to transmit the images in IoD environment.The current study introduces an Atom Search Optimization basedClusteringwith Encryption Technique for Secure Internet of Drones(ASOCE-SIoD)environment.The key objective of the presented ASOCE-SIoD technique is to group the drones into clusters and encrypt the images captured by drones.The presented ASOCE-SIoD technique follows ASO-based Cluster Head(CH)and cluster construction technique.In addition,signcryption technique is also applied to effectually encrypt the images captured by drones in IoD environment.This process enables the secure transmission of images to the ground station.In order to validate the efficiency of the proposed ASOCE-SIoD technique,several experimental analyses were conducted and the outcomes were inspected under different aspects.The comprehensive comparative analysis results established the superiority of the proposed ASOCE-SIoD model over recent approaches. 展开更多
关键词 Internet of drones atom search algorithm CLUSTERING ENCRYPTION SIGNCRYPTION
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Feature Selection with Stacked Autoencoder Based Intrusion Detection in Drones Environment
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作者 Heba G.Mohamed Saud S.Alotaibi +5 位作者 Majdy M.Eltahir Heba Mohsen Manar Ahmed Hamza Abu Sarwar Zamani Ishfaq Yaseen Abdelwahed Motwakel 《Computers, Materials & Continua》 SCIE EI 2022年第12期5441-5458,共18页
The Internet of Drones(IoD)offers synchronized access to organized airspace for Unmanned Aerial Vehicles(known as drones).The availability of inexpensive sensors,processors,and wireless communication makes it possible... The Internet of Drones(IoD)offers synchronized access to organized airspace for Unmanned Aerial Vehicles(known as drones).The availability of inexpensive sensors,processors,and wireless communication makes it possible in real time applications.As several applications comprise IoD in real time environment,significant interest has been received by research communications.Since IoD operates in wireless environment,it is needed to design effective intrusion detection system(IDS)to resolve security issues in the IoD environment.This article introduces ametaheuristics feature selection with optimal stacked autoencoder based intrusion detection(MFSOSAEID)in the IoD environment.The major intention of the MFSOSAE-ID technique is to identify the occurrence of intrusions in the IoD environment.To do so,the proposed MFSOSAE-ID technique firstly pre-processes the input data into a compatible format.In addition,the presented MFSOSAEID technique designs a moth flame optimization based feature selection(MFOFS)technique to elect appropriate features.Moreover,firefly algorithm(FFA)with stacked autoencoder(SAE)model is employed for the recognition and classification of intrusions in which the SAE parameters are optimally tuned with utilize of FFA.The performance validation of the MFSOSAE-ID model was tested utilizing benchmark dataset and the outcomes implied the promising performance of the MFSOSAE-ID model over other techniques with maximum accuracy of 99.72%. 展开更多
关键词 Internet of drones unmanned aerial vehicles SECURITY intrusion detection machine learning
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Swiss Innovation Week 2019:Home of Drones,the New High Flyer of Swiss Industry
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作者 Audrey 《China's Foreign Trade》 2019年第3期58-59,共2页
Following the successful Swiss Innovation Week(SIW)held in July 2018,the Embassy of Switzerland in China launches its 2nd edition from 12 to 14of June 2019.With Swiss drones as the brand-new theme,Switzerland’s drone... Following the successful Swiss Innovation Week(SIW)held in July 2018,the Embassy of Switzerland in China launches its 2nd edition from 12 to 14of June 2019.With Swiss drones as the brand-new theme,Switzerland’s drone ecosystem and innovation in the field of flying robots were present.According to various rankings,Switzerland is one of the most innovative countrie s in the world and also one of the most competitive co untries. 展开更多
关键词 SWISS INNOVATION WEEK 2019:Home of drones the New High FLYER of SWISS Industry
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A cloud Bayesian network approach to situation assessment of scouting underwater targets with fixed-wing patrol aircraft
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作者 Yongqin Sun Peibei Ma +1 位作者 Jinjin Dai Dongxin Li 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第2期532-545,共14页
The battlefield situation changes rapidly because underwater targets'are concealment and the sea environment is uncertain.So,a great number of situation information greatly increase,which need to be dealt with in ... The battlefield situation changes rapidly because underwater targets'are concealment and the sea environment is uncertain.So,a great number of situation information greatly increase,which need to be dealt with in the course of scouting underwater targets.Situation assessment in sea battlefield with a lot of uncertain information is studied,and a new situation assessment method of scouting underwater targets with fixed-wing patrol aircraft is proposed based on the cloud Bayesian network,which overcomes the deficiency of the single cloud model in reasoning ability and the defect of Bayesian network in knowledge representation.Moreover,in the method,the cloud model knowledge deal with the input data of Bayesian network reasoning,and the advantages in knowledge representation of cloud theory and reasoning of Bayesian network are applied;also,the fuzziness and stochasticity of cloud theory in knowledge expression,the reasoning ability of Bayesian network,are combined.Then,the situation assessment model of scouting underwater targets with fixed-wing patrol aircraft is established.Hence,the directed acyclic graph of Bayesian network structure is constructed and the assessment index is determined.Next,the cloud model is used to deal with Bayesian network,and the discrete Bayesian network is obtained.Moreover,after CPT of each node and the transformation between certainty degree and probability are accomplished;the final situation level is obtained through a probability synthesis formula.Therefore,the target type and the operational intention of the other side are deduced to form the battlefield situation.Finally,simulations are carried out,and the rationality and validity of the proposed method are testified by simulation results.By this method,the battlefield situation can be gained.And this method has a wider application range,especially for large sample data processing,and it has better practicability. 展开更多
关键词 certainty degree cloudy bayesian network(CBN) conditional probability table(CPT) fixed-wing patrol aircraft scouting underwater targets situation assessment
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Objects Detection and Recognition System Using Artificial Neural Networks and Drones
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作者 Dymitr PIETROW Jan MATUSZEWSKI 《Journal of Electrical Engineering》 2018年第1期46-51,共6页
The paper presents the digital image objects detection and recognition system using artificial neural networks and drones. It contains description based on the example of person identification system where face is the... The paper presents the digital image objects detection and recognition system using artificial neural networks and drones. It contains description based on the example of person identification system where face is the key of object processing. It describes the structure of this system and components of the learning sub-system as well as the processing sub-system (detection, recognition). It consists of the description and examples of learning and processing algorithms and applied technologies. The results of calculations of efficiency and speed of each algorithm are presented in the table and appropriate characteristics. The article also describes the possibilities of further system developments. 展开更多
关键词 Neural networks DETECTION RECOGNITION drones.
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Evaluating the Use of Drones in the Area of Transportation/Construction
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作者 Kasim A.Korkmaz Shariq I.Mohammed 《Journal of Architectural Environment & Structural Engineering Research》 2020年第1期1-4,共4页
Drones are proving out as a valuable tool and growing quickly in the world of technological advances.The applications of these vehicles are spreading widely in the areas of remote sensing,real time monitoring,goods de... Drones are proving out as a valuable tool and growing quickly in the world of technological advances.The applications of these vehicles are spreading widely in the areas of remote sensing,real time monitoring,goods delivery,security,defense,surveillance,infrastructure inspection.Although,the intent behind creating this tool was remote sensing.Smart drones will be the next big innovation and modification,which would have much wider applications especially in the field of infrastructure where it can reduce risks and lower costs.Current direct evaluation techniques are tedious,and the information caught is frequently not led in a precise manner with the areas tested not being geographically correct and the resulting reports being delivered past the point of no return.These were the reasons,which have increased the demand and usage of unmanned vehicles.In this research paper,we present critical review of main advancements of Drones in the area of transportation and agriculture.We present all the research related to civil applications in those areas and challenges including traffic monitoring,Bridge condition assessment,Roadway asset detection and many other applications related to infrastructure inspection enhancement.The paper also contributes with a discussion on the opportunities,which are opened,and the challenges that need to be addressed.Findings from the case studies,it is reported that around 25%of the bridges in united states are deficient and need continuous monitoring for enhancements to prevent any hazard.Unmanned vehicles could be a great help in monitoring these bridges and other important components of transportation,which can efficiently minimize the cost as well as the time spent on inspection for each of this component,as manual inspection requires labor and time which would be subsequently reduced by incorporating the usage of drones in the area of transportation. 展开更多
关键词 drone applications TRANSPORTATION CONSTRUCTION Civil applications
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Retarded Harrier Maneuver as a New and Efficient Approach for Fixed-Wing Aircraft to Achieve S/VTOL
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作者 Chung-Kiak Poh Chung-How Poh 《Advances in Aerospace Science and Technology》 2021年第2期81-92,共12页
Modern day VTOL fixed-wing aircraft based on quadplane design is relative<span style="font-family:Verdana;">ly simple and reliable due to lack of complex mechanical components</span><span styl... Modern day VTOL fixed-wing aircraft based on quadplane design is relative<span style="font-family:Verdana;">ly simple and reliable due to lack of complex mechanical components</span><span style="font-family:Verdana;"> com</span><span style="font-family:Verdana;">pared to tilt-wings or tilt-rotors in the pre-80’s era. Radio-controlled </span><span style="font-family:Verdana;">aerobatic airplanes have thrust-to-weight ratio of greater than unity and are capable of performing a range of impressive maneuvers including the so-called harrier maneuver. We hereby present a new maneuver known as the retarded harrier </span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">that is applicable to un/manned fixed-wing aircraft for achieving VTOL flight with a better forward flight performance than a quadplane in terms of weight, speed and esthetics.</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> An airplane with tandem roto-stabilizers is also presented as an efficient airframe to achieve VTOL via retarded harrier maneuver, and detailed analysis is given for hovering at 45° and 60° and comparison is made against the widely adopted quadplane. This work also includes experimental demonstration of retarded harrier maneuver using a small remotely pilot airplane of wingspan 650 mm.</span></span></span> 展开更多
关键词 fixed-wing Aircraft Roto-Stabilizer Vertical Takeoff and Landing Short Takeoff Harrier Maneuver Distributed VTOL System (DVS) Urban Air Mo-bility (UAM)
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