Analysis on Potential Conflict Frequency of Intersected Air Routes in Terminal Airspace Design

In order to obtain accurate conflict risks in terminal airspace design,the concept and calculation model of potential conflict frequency for intersected routes are proposed.Conflict frequency is represented by the product of horizontal conflict frequency and vertical conflict probability.The horizontal conflict frequency is derived from the probability density distribution of conflicts in a period of time.Based on the recorded radar trajectory data,the concept and model of ROUTE distance are proposed,and the probability density function of aircraft height at a specified ROUTE distance is deduced by kernel density estimation.Furthermore,vertical conflict probability and its horizontal distribution are achieved.Examples of three intersected arrival and departure route design schemes are studied.Compared with scheme 1,the conflict frequency values of the other two improved schemes decrease to53% and 24%,respectively.The results show that the model can quantify potential conflict frequency of intersected routes.

Review on artificial intelligence techniques for improving representative air traffic management capability

The use of artificial intelligence(AI)has increased since the middle of the 20th century,as evidenced by its applications to a wide range of engineering and science problems.Air traffic management(ATM)is becoming increasingly automated and autonomous,making it lucrative for AI applications.This paper presents a systematic review of studies that employ AI techniques for improving ATM capability.A brief account of the history,structure,and advantages of these methods is provided,followed by the description of their applications to several representative ATM tasks,such as air traffic services(ATS),airspace management(AM),air traffic flow management(ATFM),and flight operations(FO).The major contribution of the current review is the professional survey of the AI application to ATM alongside with the description of their specific advantages:(i)these methods provide alternative approaches to conventional physical modeling techniques,(ii)these methods do not require knowing relevant internal system parameters,(iii)these methods are computationally more efficient,and(iv)these methods offer compact solutions to multivariable problems.In addition,this review offers a fresh outlook on future research.One is providing a clear rationale for the model type and structure selection for a given ATM mission.Another is to understand what makes a specific architecture or algorithm effective for a given ATM mission.These are among the most important issues that will continue to attract the attention of the AI research community and ATM work teams in the future.

Dynamic reconfiguration for en-route airspace

As the air traffic demand is anticipated to be increased significantly in the near future,dynamic and effective allocation of the airspace resource is becoming a world-wide focus in the research field of air traffic management（ATM）.Taking the U.S.targeting the en-route airsapce,a dynamic airspace configuration（DAC） algorithm to reconfigure the airspace in consideration of higher efficiency and safety is presented.First,a modeling technique based on graph theory is proposed to generate a mathematical model for the airspace,and then,the graph model is partitioned into subgraphs for the purpose of sectorizatoin.The final step generates sector configuration with desirable geometry shape.Through analysis on the Cleveland airspace center（ZOB） in the U.S.,the algorithm is proved to be robust to time-varying traffic load.

低空空域无人机运行安全保障技术研究综述

低空空域飞行活动日趋频繁,无人机类型多样且性能差异较大,飞行过程中易与建筑物或其他航空器发生飞行冲突。为实现低空空域的规范化、安全化、精细化和智慧化管控,需不断提升保障无人机运行安全的技术手段,例如冲突风险探测、安全风险评估等。文章从无人机的轨迹预测与意图识别、低空空域飞行冲突探测、低空空域风险评估及预警告警等3方面进行了研究。首先,总结了在无人机轨迹预测和意图识别方面的研究成果和面临的问题挑战;其次,基于低空空域冲突探测形式,分析不同探测方法的优缺点;随后,围绕低空空域风险评估及预警告警技术,分析当前研究需要解决的核心问题;最后,对无人机冲突探测和风险评估技术等方面进行了展望。

Development and evaluation of low-altitude remote sensing systems for crop production management

Precision agriculture accounts for within-field variability for targeted treatment rather than uniform treatment of an entire field.It is built on agricultural mechanization and state-of-the-art technologies of geographical information systems(GIS),global positioning systems(GPS)and remote sensing,and is used to monitor soil,crop growth,weed infestation,insects,diseases,and water status in farm fields to provide data and information to guide agricultural management practices.Precision agriculture began with mapping of crop fields at different scales to support agricultural planning and decision making.With the development of variable-rate technology,precision agriculture focuses more on tactical actions in controlling variable-rate seeding,fertilizer and pesticide application,and irrigation in real-time or within the crop season instead of mapping a field in one crop season to make decisions for the next crop season.With the development of aerial variable-rate systems,low-altitude airborne systems can provide high-resolution data for prescription variable-rate operations.Airborne systems for multispectral imaging using a number of imaging sensors(cameras)were developed.Unmanned aerial vehicles(UAVs)provide a unique platform for remote sensing of crop fields at slow speeds and low-altitudes,and they are efficient and more flexible than manned agricultural airplanes,which often cannot provide images at both low altitude and low speed for capture of high-quality images.UAVs are also more universal in their applicability than agricultural aircraft since the latter are used only in specific regions.This study presents the low-altitude remote sensing systems developed for detection of crop stress caused by multiple factors.UAVs,as a special platform,were discussed for crop sensing based on the researchers'studies.

Dynamic Air Route Open-Close Problem for Airspace Management

Dynamic airspace management plans and assigns airspace resources to airspace users on demand to increase airspace capacity. Although many studies of air traffic flow management （ATFM） have sought to optimally allocate air traffic to get the best use of given airspace resources, few studies have focused on how to build an efficient air traffic network or how to adjust the current network in real time. This paper presents an integer program model named the dynamic air route open-close problem （DROP）. DROP has a cost-based objective function which takes into account constraints such as the shortest occupancy time of routes, which are not considered in ATFM models. The aim of DROP is to determine which routes will be opened to a certain user during a given time period. Simulation results show that DROP can facilitate utilization of air routes. DROP, a simplified version of an air traffic network constructing problem, is the first step towards realizing dynamic airspace management. The combination of ATFM and DROP can facilitate decisions toward more reasonable, efficient use of limited airspace resources.

A new skeleton based flying bird detection method for low-altitude air traffic management

In low-altitude air traffic management, non-cooperation targets are the greatest threat to security of low-flying aircraft. Among various aviation fatalities, flying bird is the main factor with the highest risk and directs economic losses amounted to nearly 10 billion US dollars each year.Therefore, Flying Bird Detection(FBD) has attracted considerable attention in low-altitude air traffic management. In this paper, we propose a skeleton based FBD method via describing bird motion information with a set of key poses. To overcome the variability of birds, the skeleton feature is selected as a relatively fixed and common characteristic for the pose appearance of flying bird. Based on the geometric topology among some key parts of bird body, a set of key poses can be described by some extracted skeleton features, which are used to represent the bird motion information. Aimed at robustly handling with the pose variations, multiple pose-specific classifiers are individually trained to learn the representative poses of the flying bird. At the detection stage,the flying bird skeleton features are combined with extracted key-pose sets to perform the flying bird classification task from each image. Afterwards, the key-frame pose-change set and the consistency of the classification results from sequent images are employed to validate the final detection results.Experiments on flying bird datasets demonstrate the effectiveness and efficiency of the proposed method.

基于改进支持向量机的空域交通态势识别方法

为了准确分析空域交通态势,针对当前空域交通态势感知中管制行为因素难以度量的问题,从多种管制员工作负荷的角度进行量化分析。借助全空域及机场模型软件(Total Airspace and Airport Modeller,TAAM)建立空域仿真模型,研究了栅格化空域场景下基于改进支持向量机(support vector machine,SVM)的空域交通态势识别方法。通过对比不同的栅格化方案,结合管制员实际运行经验确定栅格形状和尺寸,以边长为25 km的六边形为最小单元,对目标空域进行栅格化处理。在引入多种管制负荷的基础上同时考虑导航设施的分布情况,建立空域交通态势识别指标体系,运用K-means聚类算法对降维后的仿真样本数据进行聚类分析,获取先验分类数据。在支持向量机模型的基础上,引入麻雀搜索算法(sparrow search algorithm,SSA),构建基于麻雀搜索算法优化支持向量机(SSA-SVM)的空域交通态势识别模型。依据适应度对解集进行划分,对模型关键参数核函数参数σ和惩罚系数C进行优化,确定了1组泛化能力强同时避免过拟合问题的参数组合,并将栅格化空域交通态势划分为4个等级。以西安区域管制区为对象开展仿真实验,结果表明:与基于遗传算法优化支持向量机(GA-SVM)的空域交通态势识别模型相比,SSA-SVM模型克服了GA-SVM模型确定的的过拟合问题,平均分类识别准确率提高2.50%,最佳分类识别准确率提高1.73%;在176个栅格中,拥堵态、拥挤态和平稳态栅格个数分别为26、18和51,模型识别结果与基于管制员经验划分的复杂空域相比,覆盖率可达95%,验证了提出方法对空域交通态势识别及降低管制员工工作负荷的有效性。

考虑航段复杂度的机场终端区进场程序设计与评估

机场附近的进近空域通常是限制机场航班量增长的瓶颈。随着进近空域内日益增长的空中交通,管制员与飞行员的通信和工作负荷持续增加,航班延误频发。为了进一步提升机场进近空域容量,先进的技术和方法不断被应用于空中交通管理中。近年来,在世界各主要繁忙机场逐步推广点融合系统(Point Merge System),旨在通过新的进场程序实现进场航班高效排序和连续下降运行,解决进场交通流汇聚问题并优化排序间隔管理。然而,目前很少关于如何结合机场附近空域结构设计点融合系统的研究。本文以南京禄口国际机场为例,提出了航段复杂度评估方法,评估了当前空域的航段复杂度,识别空域运行瓶颈,选取融合点位于HFE和OF方向进场轨迹的交汇点,交通流开始汇聚整合的定位点作为程序融合点,并以此为基础设计了点融合系统。通过计算机仿真和雷达模拟机仿真,并对其不同运行方式下的航班延误和机场流量进行对比,验证了点融合系统的有效性和先进性。本文的研究为其他机场设计并实施点融合系统可提供参考。

基于可达集的无人机低空飞行冲突解脱算法

针对无人空中交通管理(UTM)中的冲突解脱问题,提出了以可达集分析为基础的实时避撞算法。该算法可用于城市低空环境中的密集交通流空域,保证无人机(UAV)飞行过程的安全性。基于相对运动的概念,通过分析平面空域中的飞行博弈问题对避撞系统进行建模,同时利用水平集方法和最优控制理论对无人机的可达集进行分析和计算,使用机载传感器获取无人机与周围物体的信息,为每架无人机提供新的避撞策略。通过3种不同空域环境的飞行案例进行仿真实验,验证了该策略不仅可以得到平滑的飞行路径,实时安全地解决冲突解脱问题,而且针对合作/非合作目标均有效。

基于有限PMU配置与空域信号生成的配电网故障定位方法

随着配电网网络结构日益复杂,目前因成本限制有限安装的同步相量测量装置所采集到的数据难以保证配电网故障的全局可观性。为此,基于图卷积神经网络算法建立了一种可适用于含有限电源管配电网络的全局空域故障信号生成模型,提出了一种有限电源管安装下准确度较高的配电网故障线路定位方法。通过搭建20个节点的三相平衡配电网验证了所提模型与其他基准模型相比定位准确度更高。在电源管非全面配置时可达到98.8%的定位准确度,且模型对过渡电阻具有鲁棒性。

基于改进元胞自动机算法的航路网络规划研究

为优化空域资源、提升空域容量、缓解空中交通拥堵,本文研究了“三区”规避情况下的航路网络规划问题。首先通过栅格法进行空域离散化建模,将空域信息二值化,以此实现“三区”规避;接着以航路总长度最小为目标,考虑非直线系数、流量约束等建立数学模型,在寻路过程中添加距离优先系数和碰撞风险系数,利用元胞自动机算法求解,并在此基础上增加了路径平滑过程;最后以广州飞行情报区航路网络规划为实例进行验证。结果表明,相比于现行航路,航路长度有效缩短、航路点个数减少且航路的非直线系数也有所降低,验证了改进的元胞自动机算法的有效性,对现实的航路网络规划具有重要的参考意义。

空中交通智能化管理的科学与技术问题研究

空中交通正呈现大流量、强耦合、高时变特点,为保障运行的顺畅、高效与安全可靠,需要发展以数字化、自主化、协同式为典型特征的空中交通智能化管理模式。本文在阐述当前及未来一段时期内空中交通管理需求背景的基础上,立足发展趋势,从交通管制、空域管理、流量控制3个方向剖析了传统空中交通管理面临的挑战,凝练了空中交通智能化管理涉及的航空器与空管基础设施相互作用机理和模式、基于可接受风险的航空器间隔空地协同控制、多要素形态非一致规则的空域运行建模优化、高密度空中交通流演化机理与拥堵传播特性等基础科学问题。研究建议,集成应用卫星互联网、大数据、数字孪生、云计算等前沿技术,从航空器、空域、管制决策、运行等方面着手构建空中交通智能化管理技术体系,从而确立新一代空中交通管理系统的技术基础。

空域容量评估的理论与方法研究综述

针对目前对空域容量评估理论和方法的研究,本文从机场终端区容量评估、航路扇区容量评估、区域容量评估方面进行阐述,介绍国内外相关研究现状,然后结合各空域容量的限制约束及影响因素,分析比较容量评估的方法和工具,总结得出空域容量评估的未来趋势以及对我国空域容量评估的发展启示。

基于数字化空域系统的城市无人机管理对策研究

随着无人机产业向大众化发展,传统的空中交通管理模式已无法适用于城市环境下的空中交通运行。信息技术的不断延伸为低空空域管理带来更多可能性。本文基于数字化低空空域系统,从政策制度、无人机运行管控、数字低空建设等方面构建城市无人机管理方案。首先,从无人机与空中交通管理层面梳理了当前城市无人机管理所面临的核心难点与关键科学问题;其次,围绕政策制度、无人机运行管控、数字低空建设对关键技术进行研究;最后,针对城市无人机管理提出有效建议,以促进未来先进空中交通新模式的发展。

关于消防无人机限制空域使用申请的实践探索

近年来,随着民用无人机行业的迅猛发展,各行业加快了对无人机技术的应用,在应急救援领域,无人机在各类灾害事故救援中起到了良好的辅助作用。然而无人机给人们带来诸多便利的同时,其伴随的窃取国家机密、影响民航安全、侵犯个人隐私等问题也日益凸显。如何合法合规、安全使用无人机,已经成为大家愈发关注的课题。

空域复杂性建模

下一代空中交通管理系统致力于推进管理决策中心从地面转向空中,实现统筹分布-集中决策模式,提高交通服务能力,适应未来航运需求。为探索空域系统承载复杂交通的能力,空管业界对以动态密度为代表的空域复杂性模型进行了大量研究。运用复杂性学科研究的基本思想,以对空域状态进行客观描述为重点,反映空域以及其中交通关系的变化过程,提出了综合迫近、几率和连携因素的空域复杂性模型,最后,通过仿真实验数据和广州地区的实际运行数据验证了模型的可行性。弥补了空域状态评估领域航空器计量方法的不足。

管制扇区优化划分的方法及计算机实现技术

扇区划分是空中交通管理的一项重要工作 ,它直接影响空域的容量和安全性。分析、确定了管制空域结构拓扑描述的数学模型、管制员的管制工作负荷统计方法、工作负荷计算的数学模型等扇区优化设计工作的理论基础 ,建立扇区划分的数学方法 ,并编制了基于管制员工作负荷的扇区优化应用软件 。

遗传算法在飞行冲突解脱中的应用

随着空中交通流量的增加 ,我国的空中交通系统面临着越来越严重的航线拥挤 ,飞行冲突变得日益严重。自由飞行是解决这一问题的有效方法 ,即允许飞行员选择最合适自己的飞行航线和飞行速度 ,其优势显而易见 ,但同时增加了管制员管制监控的难度 ,基于遗传算法的自由飞理论能有效地解决这一问题。本文论述了该方法在飞行冲突解脱中的应用。

交叉航路空域的时隙可用性评估方法

为了增加空域使用效率,建立了交叉航路入口放行策略模型.对多种交叉航路及放行策略组合,提出了新的空域时隙资源可用性评估方法,研究了新策略下航路长度、航路交叉角和放行偏离角对交叉航路时隙可用性的影响.仿真结果表明:当放行偏离角一定时,增加航路长度可有效提升时隙资源可用率,偏离角为10°、20°和30°时的最大时隙可用率分别为82%、90%和97%;航路长度具有边际效应,当航路长度超过阈值时,再增加航路长度不会提高时隙资源可用率;在航路长度、放行偏离角相同的条件下,增加航路交叉角可增加时隙资源可用率.