基于DSP和GPS定位航空管制空域辅助监测系统浅析

本文主要介绍在航空管制工作中飞行空域监测的意义,以及逼近空域的飞行目标到空域距离的计算方法。本文介绍的辅助监测系统主要辅助部队航空管制员在部队训练和演习过程中,监测空域与航路分布密集区的飞行活动,从而减轻管制人员的工作强度,提高航空管制的效率,及时发出危险告警,有力保障空中交通安全。     

A study of aircraft taxi performance for enhancing airport surfacetraffic control

In view of the ever-increasing air traffic, much attention in air traffic management research has been given to improving arrival and departure efficiency. As air traffic begins and ends at the airport, the issues of taxi delays and ground incursions are becoming more evident. The paper considers the surface-traffic problem at major airports and envisions a collaborative traffic and aircraft control environment where a surface traffic automation system will help coordinate surface traffic movements. Specifically, the paper studies the performance potential of high-precision taxi toward the realization of such an environment. A state-of-the-art nonlinear control system based on feedback linearization is designed for a detailed B-737 aircraft taxi model. The simulation model with the nonlinear control system is evaluated extensively in a scenario representing the demanding situation of an arrival aircraft crossing an adjacent active runway immediately following its own landing. The evaluation establishes the potential of an automated system to achieve high-precision taxi control, including the ability to comply with taxi clearances with tight time margins. Such a high-precision taxi capability reduces the time margin required for clearing taxiing aircraft to cross active runways, thus increasing the opportunity for issuing such clearances, which in turn reduces the need for aircraft to hold short at the runways to wait for the opportunity for crossing. The results from the analyses provide insight into future aircraft operational capabilities toward the design of the envisioned surface traffic automation system. Moreover, the nonlinear control design serves as a preliminary study for future auto-taxi functional development     

ATOMS: Air Traffic Operations and Management Simulator

In this paper, we introduce the air traffic operations and management simulator (ATOMS), which is an air traffic and airspace modeling and simulation system for the analysis of free-flight concepts. This paper describes the design, architecture, functionality, and applications of the ATOMS. It is an intent-based simulator that discretizes the airspace in equal-sized hyper-rectangular cells to maintain intent reference points. It can simulate end-to-end airspace operations and air navigation procedures for conventional air traffic, as well as for free flight. Atmospheric and wind data that are modeled in the ATOMS result in accurate trajectory predictions. The ATOMS uses a multiagent-based modeling paradigm for modular design and easy integration of various air traffic subsystems. A variety of advanced air traffic management (ATM) concepts that are envisioned in free flight are prototyped in the ATOMS, including airborne separation assurance (ASA), cockpit display of traffic information (CDTI), weather avoidance, and decision support systems (DSSs). Experimental results indicate that advanced ATM concepts make a sound case for free flight; however, there is a need to investigate and understand their complex interaction under nonnominal scenarios.     

Benefits of direct-to tool in National Airspace System

Initiatives in air traffic management both in the United States and in Europe are aimed at providing air traffic controllers with automation tools to separate traffic, meet time constraints required for traffic flow and accommodate route preferences of users such as airlines. These efforts are expected to result in removal of restrictions on users preferred routes without compromising safety. Thus, aircraft will be able to fly optimal routes such as great circle and wind-optimal routes. NASA has developed the design for a new automation tool, referred to as the direct-to tool, which advises the controller on direct time-saving routes for any aircraft irrespective of levels of equipage. In contrast to earlier studies on the potential benefits of direct routes in the National Airspace System, the objective of the paper is to evaluate the benefits based on a controller tool. The paper describes the benefits of applying this algorithm to the 20 air route traffic control centers within the United States. Benefits are measured in terms of the total time savings accrued by flying the direct route. Results are described for three different implementations dependent on the search region bounding each air route traffic control center. The first region exactly encloses the air route traffic control center airspace, the second is the smallest rectangular bounding region while the third is a bigger rectangular bounding region approximately twice as large as the second region. It is shown that the application of the direct-to routing algorithm does not significantly alter the number of conflicts and their spatial distribution compared to the case in which the aircraft fly along the airways. The results presented in the paper suggest that the direct-to routing algorithm can provide significant cost savings to the users without adversely impacting the air traffic management functions     

探索TCASⅢ水平避撞及冲突决策咨询S算法

随着我国国民经济的高速增长,空中交通流量剧增,发生空中冲突的可能性也不断增加.为此研究冲突检测和解脱技术等冲突咨询算法也就成为了必然.TCAS是一种机载空中交通防撞系统,目前对如何正确使用尚没有完整的标准与规范,了解TCAS的工作原理是飞行员正确使用TCAS保证空中交通安全的基础.基于TCASⅢ机载防撞系统,对民航飞行中冲突检测与咨询算法进行了研究,建立了冲突解脱模型,给出了基于TCASⅢ机载防撞系统的多机水平防撞冲突决策咨询算法模型.     

An experimental approach to measuring the effects of a controllerconflict probe in a free routing environment

The unstructured traffic environment that is gradually evolving in the National Airspace System may necessitate decision aiding tools to help controllers manage aircraft traffic efficiently and within acceptable safety and workload levels. An experiment was designed to assess the effect of conflict detection and trial planning resolution aids and traffic conditions on the performance of controllers and the efficiency of flight. Twelve controllers participated in a high-fidelity simulation study in the Indianapolis Center dynamic simulation facility using the user request evaluation tool (URET). Study results indicated that URET clearly improves the acceptability of operations and may enhance safety, particularly in the unstructured environment. In addition, the study findings strongly support a shift toward more strategic air traffic control with conflict probe as well as a significant increase in the contribution of the D controller to the primary sector tasks. Because of study limitations, it was not possible to associate any quantitative estimates of airspace user benefits with the potentially more efficient resolution strategies. The results and experimental approach are discussed in terms of their contribution to measurement methods and issues in the evolutionary progression toward a free flight-based air traffic system     

Neural Networks for Real-Time Traffic Signal Control

Real-time traffic signal control is an integral part of the urban traffic control system, and providing effective real-time traffic signal control for a large complex traffic network is an extremely challenging distributed control problem. This paper adopts the multiagent system approach to develop distributed unsupervised traffic responsive signal control models, where each agent in the system is a local traffic signal controller for one intersection in the traffic network. The first multiagent system is developed using hybrid computational intelligent techniques. Each agent employs a multistage online learning process to update and adapt its knowledge base and decision-making mechanism. The second multiagent system is developed by integrating the simultaneous perturbation stochastic approximation theorem in fuzzy neural networks (NN). The problem of real-time traffic signal control is especially challenging if the agents are used for an infinite horizon problem, where online learning has to take place continuously once the agent-based traffic signal controllers are implemented into the traffic network. A comprehensive simulation model of a section of the Central Business District of Singapore has been developed using PARAMICS microscopic simulation program. Simulation results show that the hybrid multiagent system provides significant improvement in traffic conditions when evaluated against an existing traffic signal control algorithm as well as the SPSA-NN-based multiagent system as the complexity of the simulation scenario increases. Using the hybrid NN-based multiagent system, the mean delay of each vehicle was reduced by 78% and the mean stoppage time, by 85% compared to the existing traffic signal control algorithm. The promising results demonstrate the efficacy of the hybrid NN-based multiagent system in solving large-scale traffic signal control problems in a distributed manner.     

航站楼空调送风末端系统经济性分析和优化模型

为提供空调末端形式的优化设计依据,提出了空调末端系统运行成本的主要影响因素,分析确定了影响因素的变化范围,并建立了空调末端系统运行多参数经济分析模型,分析了各参数的影响程度。结果表明,运维成本占比不高,人工成本的差别不影响成本变化趋势,但运行时长对运行成本的影响较大,运行时长越长,机组效率的影响越大。小风量分布式末端机组经济节能性好,控制策略灵活。整体式空调机组具有较广的适应性,对于大部分航站楼的空调末端系统都是最优解。适合对于电价政策复杂的情况,应具体问题具体分析,代入模型得出准确的优化方案。该研究为交通建筑空调末端系统的优化运行及设计提供参考。     

Measurement of road traffic using spatial frequency analysis of TV images

This paper deals with distinguishing vehicle types in automobile traffic flow by image processing. In the traffic flow, traffic jams always occur. Traffic jams increase driver stress and result in time delays, traffic accidents, and air pollution. Thus, it is important to provide traffic information such as vehicle volume and to distinguish vehicle types. In this paper, we attempt to do so by using vehicle width. The general measurement of traffic flow is performed using an ultrasonic sensor. But the system is expensive, and the method is not useful for automobile traffic flow. Thus, we have developed a simple system using a portable camera, a personal computer, and a digital signal processor. This system performs width measurement of vehicles in real time. The measurement method uses the Fourier transform and has the advantage of robustness to noise. Since frequency analysis for width measurement of vehicle images differs from road image analysis, we measure the vehicle volume and distinguish vehicle types in real time. © 1998 Scripta Technica, Inc. Electr Eng Jpn, 121(3): 60–66, 1997     

Basic study on traffic information system using LED traffic lights

The vehicle information and communication system (VICS) is starting to become practicable. The infrared system of a VICS detects vehicles on the road by using optical beacons to control traffic and to supply real-time traffic information. But it needs an enormous budget because the optical beacons must be located on every lane of the road throughout the country. We propose a traffic information system using existing LED traffic lights, and focus on its visible rays and power used for traffic control, the number and location of the traffic lights, and the movement toward LED traffic lights. We design the best service area not to interfere with other service areas and analyze its basic performance such as the suitable modulation, required SNR and the amount of receivable information     

Receding horizon control for aircraft arrival sequencing and scheduling

Airports, especially busy hub airports, proved to be the bottleneck resources in the air traffic control system. How to carry out arrival scheduling and sequencing effectively and efficiently is one of main concerns to improve the safety, capacity, and efficiency of the airports. This paper introduces the concept of receding horizon control (RHC) to the problem of arrival scheduling and sequencing in a dynamic environment. The potential benefits RHC could bring in terms of airborne delay and computational burden are investigated by means of Monte Carlo simulations. It is pointed out that while achieving similar performance as existing schemes, the new arrival scheduling and sequencing scheme significantly reduces the computational burden and provides potential for developing new optimization algorithms for further reducing airborne delay.     

基于奇异值分解的风电场杂波微动特征提取

风电场作为一种特殊的大型建筑物,会影响航管监视雷达对飞机目标的准确探测。同时,由于风电场通常分布在某一大面积区域,风轮机之间具有多径传输特性,进而会影响航管监视雷达对飞机目标的定位和测速。因而,分析风电场杂波的微动特征有助于检测和识别风电场杂波信号,提高雷达探测目标的准确性。基于航管监视雷达风电场回波信号模型,利用奇异值分解技术分析了风电场回波信号的微动特征,并构造相应的特征量实现其微动特征的提取。同时,在飞机目标存在背景下,提取了风电场回波的微动特征,并将其与飞机目标的多普勒特征进行对比分析,仿真结果证明了所提方法的有效性。     

张涛，张文平，王炎基于模糊控制原理的智能交通信号控制系统的设计

为了解决交通拥挤问题,根据不同方向的车辆流量合理地安排交通路口通行时间,设计了一种采用模糊控制原理的智能交通信号控制系统。详细给出交通信号模糊控制器的结构原理和设计结果。并设计以AT89 C51单片机为主控制器的交通信号控制系统,用以验证设计的模糊控制器。系统采用模糊控制原理对交通信号进行智能调整,实现根据车流量自动调整不同方向交通信号的点亮时间和通行时间。模糊控制器的设计过程与仿真结果表明：模糊控制原理是完成智能自动调整交通信号的理论基础,并具有实际的应用价值。     

智能变电站网络流量监测系统研究

文章从智能变电站站控层网络流量监测系统的需求出发,提出了一种检测智能变电站的网络流量监测系统解决方案。重点阐述了智能变电站站控层网络流量监测系统的总体结构设计、61850MMS数据报文的采集和流量数据统计等内容,该系统的实现可以有效地监控网络流量状况。     

基于低压传输和供电的LED交通信号灯控制系统设计

该文设计了一种基于低压传输和供电的LED交通信号灯控制系统,采用36 V低压传输方式实现对LED交通信号灯的控制和驱动,并将传输的低压控制信号作为LED交通信号灯的供电电源。该系统可以适应较宽的输入电压变化范围,从而解决了低压信号在传输中存在的线损问题,保证了系统对LED交通信号灯的可靠控制。     

Multiairport Capacity Management: Genetic Algorithm With Receding Horizon

The inability of airport capacity to meet the growing air traffic demand is a major cause of congestion and costly delays. Airport capacity management (ACM) in a dynamic environment is crucial for the optimal operation of an airport. This paper reports on a novel method to attack this dynamic problem by integrating the concept of receding horizon control (RHC) into a genetic algorithm (GA). A mathematical model is set up for the dynamic ACM problem in a multiairport system where flights can be redirected between airports. A GA is then designed from an RHC point of view. Special attention is paid on how to choose those parameters related to the receding horizon and terminal penalty. A simulation study shows that the new RHC-based GA proposed in this paper is effective and efficient to solve the ACM problem in a dynamic multiairport environment     

基于SPCE061A语音识别技术的智能交通灯设计

本文采用的是以凌阳16位SPCE061A单片机为核心,设计的智能交通灯控制系统。充分利用其在语音识别技术方面的优越’陛对交通灯控制系统做了智能化改进,通过语音播放配合完成交通灯控制的一般过程,并能对外部紧急情况（警笛声）进行语音识别,实现交通灯的智能控制,具有一定实用价值和广阔的发展前景。     

基于PLC的回转式空预器漏风控制系统

叙述了基于PLC的回转式空预器漏风控制系统的组成、工作原理及软件的各项功能。着重介绍了可编程控制器(PLC)的结构特点和软件设计。     

基于PLC及触摸屏的隧道通风系统的设计

根据公路隧道的特点,提出了一种基于PLC及触摸屏技术的隧道通风控制系统的设计。将PLC、触摸屏、变频器三者有效结合,利用传感器在实时检测隧道内环境的基础上,通过PLC控制变频器驱动隧道内风机的运行,优化隧道内空气质量的同时也节约了能源。触摸屏的引入能够实现对系统工作全程的实时自动监控,最后利用计算机模拟技术实现了对该控制系统的整体模拟和调试。实验证明,该系统运行顺畅,性能可靠,人机交互界面友好,自动化水平有效提高,具有良好的市场前景及应用价值。     

Control of Freeway Traffic Flow in Unstable Phase by $H_{infty}$ Theory

This paper devises a freeway controller that is capable of stabilizing traffic flow when the traffic system is in the unstable (congested) phase, in which a shock wave is likely to occur in the presence of any inhomogeneity and where the system is on the verge of a jam condition. Two types of traffic controllers are developed through the use of either a speed command approach that can be implemented in an intelligent transportation system (ITS) or ramp metering that is a typical way of preventing a freeway from overloading. By means of the feedback linearization technique, the discretized macroscopic traffic flow model is reformulated, in which the desired change of volume in each section is treated as a virtual input. By exploring the casual relations among density, speed, and flow change, the corresponding speed commands can be determined. The traffic flow control problem is formulated as an H_infin control design problem so that uncertainties that are associated with the macroscopic model can be taken into account. Simulations show that the devised controller can effectively stabilize the traffic flow in the unstable phase. Design flexibilities associated with the method are also discussed.