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基于历史数据的空中改航算法研究  [PDF]
陈正茂,林毅,杨波
- , 2018, DOI: 10.15961/j.jsuese.201700538
Abstract: 中文摘要: 改航是航班运行过程中应对恶劣天气、军事活动、流量管控等突发情况的重要策略。作者提出一种挖掘历史雷达数据特征的改航算法。算法首先综合考虑改航路径的经济性、安全性、航路特征和容量影响等因素建立改航约束条件,对航班可能的改航区间的航路通路进行分析初选,确定最优的改航区间及其满足改航约束条件的一系列关键点序列。随后基于航班在历史雷达数据中的位置信息分析关键点序列航段执行情况,结合该航段计划航班数据,提出了适用于改航关键点选择的航段利用率计算方式,并在此基础上确定改航路径的最优关键点序列。以航班飞行过程中的速度矢量为建模对象,通过机器学习算法挖掘经过关键点序列航段的航班飞行运动模式。采用混合高斯模型对航班速度矢量建模和参数学习;利用马尔科夫蒙特卡洛采样算法预测航班改航过程中的速度矢量序列。最后利用匀加速运动学方程预测出完整的改航路径。通过某大型流量管理系统的应用实践证明,在考虑了改航约束条件和航段历史运行情况(利用率)等因素下的改航策略符合航班的实际运行情况。同时算法还能以高精度预测航班的改航轨迹,为改航路径相关区域的流量管理提供数据支撑。本文的改航算法能很好的解决航班在飞行过程中的改航问题。
Abstract:Rerouting is an important strategy to deal with bad weather, military activities, traffic flow control and other emergency situations in the process of flight operation. An improved rerouting algorithm based on mining features of historical radar data is proposed. Firstly, reroutingconstraints are established by taking the economy, security, route features, and the impact of traffic flow and capacity into consideration. A rough process is made to select the optimal rerouting zone and possible key-point sequences which meet those constraints for rerouting.The routes duringhistorical flight operations are analyzed by the positions of historical flights. Combining with the flights whose plan path contain the given route, a utilization representation is proposed to select the preferred key point. Then, the optimal key-point sequence is obtained by analyzing its utilization from historical radar data. Taking the velocity vector as the modeling object, the machine learning algorithm is used to mine the flight pattern of the route segment. Gaussian Mixture Model is applied to model the distribution of velocity, and Markov chain Monte Carlo is used to predict the velocity sequence during rerouting. Finally, the whole rerouting path is planned by kinematics equation with constant acceleration rules. The application of a large-scale traffic management system demonstrates the high practicability ofthe proposed algorithm with considering the actual operating conditions of flight. The proposed approach can also predict the trajectory of rerouting flights, which provides the data supportfor the air traffic flow management in the rerouting path areas. Therefore, the rerouting issue of flight can be solvedreasonably and efficiently.
航弹SINS/GPS组合导航系统半实物仿真试验设计  [PDF]
刘敏,王保成,刘藻珍
北京理工大学学报 , 2004,
Abstract: 针对某型远程航空弹药SINS/GPS组合导航系统的组成,设计了SINS/GPS组合导航的半实物仿真试验框架结构,探讨了在试验过程中多机时钟同步的问题,检验了捷联惯导系统导航计算机的解算性能和GPS信息的修正效果.试验结果表明,捷联惯导系统的算法正确,解算精度和解算时延满足控制系统的要求,GPS信息修正效果良好,SINS/GPS组合导航系统可以应用到航空弹药的制导与控制系统中.
危险天气下基于多重morphin算法的终端区三维实时改航方法  [PDF]
张兆宁,魏中慧?
南京航空航天大学学报 , 2015,
Abstract: 基于多重morphin算法,建立了终端区三维实时改航方法。该方法首先根据航空器当前飞行状态按不同的转弯角和爬升/下滑角生成一组弧线,随后在每条弧线的末端按同样方式反复运行,形成若干条由弧线组成的路径,最后对所有路径进行综合评估,找到当前时刻的改航路径。算例分析表明,该方法提供的改航路径可以保证航空器运行的安全与高效,在危险天气出现时更加充分地利用终端区空域资源,同时计算时间短、可行性高。
基于人工势场算法的改航路径规划  [PDF]
徐肖豪,李成功,赵嶷飞,李雄
交通运输工程学报 , 2009,
Abstract: 在恶劣天气或流量受限条件下,建立了基于人工势场算法的改航路径规划模型。考虑空中交通管制程序和飞行性能等约束条件,采用线性拟合的方法对初始改航航路径进行分段拟合,消除振荡点和误差较大的离散点;对拟合后的航段通过截弯取直的方法,去除多余的转弯点,生成最终的改航路径。仿真结果表明现行的沿扩展受限区边界绕飞的改航路径长度为532.299km,而采用新改航规划模型生成的改航路径长度为455.924km,在没有增加额外转弯点的条件下,航线长度减少了14.35%,因此,采用该规划方法可安全有效地避开飞行受限区域。
动态突发天气下同高度层改航模型和算法研究  [PDF]
王莉莉,周娟
武汉理工大学学报 , 2014,
Abstract: ?针对动态移动突发天气下同高度层的改航问题,建立了水平影响范围较小(小尺度)的突发天气(如雷暴)在同一水平面的改进威胁概率模型。考虑了改航偏离预定航路飞行的代价,建立了新的以最短航程为目标的改航模型。针对静态和不同动态移动情况下的突发天气,分别给出了相应的改航最优路径分析。并基于航程最短,设计了启发式算法对3种不同的场景进行算例仿真。仿真结果表明,该模型和算法是有效可行的,可以很好地处理这类改航问题,为航空器规划出一条安全的相对经济的改航路径以回避各种突发天气。
?横轴改?  [PDF]
程滋民
地质与勘探 , 1957,
Abstract: 103?利用500m?机?横?改?成300m??用横?,解决了备件缺乏??。其方法是将500m?横轴的键槽用雷焊填补,再车成300m转机横轴的设计尺寸,即可使用.
管钳子改??活  [PDF]
直爽
地质与勘探 , 1957,
Abstract: ?探??常用的工具――管?子,在工作中损坏是?多的,特?是?子?和?子箍更易?坏,而?子把损坏的?少。因此利用?子把再加工改??活成管?子是一?有效的节?措施。105勘探?已??用?一方法,解?了管?子改??活?题。他们的改??程是:???的???加?剁?,每????可?成????。剁?后,再加?至可??度(?1150°~200℃左右),?行?加工成?子?形?,再???工加工即成成品。其次再利用??粒??(如?之1)改??子箍,首先作成如?之2及3所示的???模,其中3?芯模,4??模。具?作法是???粒??按改?管?子箍所需的?度在?床上切好,放在?中加?,
Initial Alignment for SINS based on Low-cost IMU  [cached]
Jiong Yi,Lei Zhang,Rong Shu,Jianyu Wang
Journal of Computers , 2011, DOI: 10.4304/jcp.6.6.1080-1085
Abstract: The initial alignment is vital to the strapdown inertial navigation system (SINS). In this work, an efficient initial alignment method for SINS based on a six-degree of freedom inertial measurements unit (IMU) is proposed. The three dimensional linear accelerations and angular rates are acquired from a data acquisition board which contains a low-cost IMU. Preprocess the gyro data and modeling the SINS error model for initial alignment. Analysis the observability of this SINS error model and then simplify the model based on the observability. A kalman filter is conducted to estimate the misalignment angle. The results show that the initial alignment method proposed in this paper is advisable for a SINS based on low-cost IMU on a stationary base.
The Application of Federated Kalman Filtering in SINS/GPS/CNS Intergrated Navigation System  [cached]
DENG Hong,LIU Guang-bin,CHEN Hao-ming,DENG Chun-lin
International Journal of Wireless and Microwave Technologies , 2012, DOI: doi: 10.5815/ijwmt.2012.02.03
Abstract: Federated filter was an important method to estimate high-precision navigation parameters based on “SINS/GPS/CNS”. A no-feedback federated filter with UD_UKF algorithm was designed in the paper, a threetime amendment scheme to correct navigation parameters was designed at the same time and the mathematical model of SINS/GPS/CNS was established in launch inertial coordinate system too. The paper discussed the simulation conditions and a lot of simulations were carried out to compare 2 aspects: (1)the performance between four navigation mode, which respectively is SINS, SINS/GPS, SINS/CNS, SINS/GPS/CNS;(2)the estimate precision of federated filter and that of centralized Kalman filter. The results of simulation showed that the designed federated filter and amendment scheme based on SINS/GPS/CNS had high estimate precision and led to gain high hitting precision of ballistic missile, that is to say position errors were less than 20 meter and velocity errors were less than 0.1m/s in simulation.
三层滤料滤床的合理选定  [PDF]
李镜明
武汉理工大学学报 , 1981,
Abstract: ?本文旨在阐明三层滤料滤床结构特点的基础上,首先讨论滤床的规格(即滤床材料、级配和厚度),其中包括一般要求,选定方法和实例。其次分析影响滤床规格的几个因素,然后根据实情况怎样调整滤床规格。最后提出了控制三层滤料分层的原理,可作为滤床设计的参考。
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