ASTRID: Automatic SCOOT traffic information database
ASTRID: Automatic SCOOT traffic information database
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ASTRID：自动SCOOT交通信息数据库
DOI：
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发表时间：
1990
期刊：
影响因子：
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通讯作者：
M. McDonald
中科院分区：
文献类型：
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作者：
N. Hounsell;M. McDonald
SCOOT（分裂周期优化偏移技术）交通响应城市交通控制（UTC）系统的主要目的是优化网络中的信号配时，以提供最小的总延迟。然而，在优化过程中，SCOOT提供了丰富的交通信息，这些信息可能对各种目的有用。本研究报告介绍了对现有数据的调查、数据的有用性和潜在应用，以及用于处理、储存和分析数据的基于微型计算机的数据库系统的开发、生产和演示。由南安普顿大学为运输和道路研究实验室（TRRL）交通运营部进行的SCOOT可获得的交通数据可以在各种详细程度上获得。从地理上讲，这可能会从单个链路的数据到整个区域的聚合数据有所不同，可能的时间聚合从一秒到五分钟或更长。根据对发给地方当局、区域办事处和运输部政策司抽样调查表的答复，确定了更精确的数据要求。数据库系统在与SCOOT计算机相连的IBM PC（或兼容）微型计算机上运行。该系统主要是菜单驱动的，并在安装时和随后的数据处理和分析中纳入了一些用户定义的选项。介绍了用户可在安装时定义的一些关键参数，并为大多数参数提供了选择适当输入值的指导，以及默认值。数据处理包括由微型计算机接收“原始”SCOOT信息，将该数据在线剥离到其最小大小（例如删除重复的数据描述符），并将数据聚合到其用户定义的聚合水平。扫描区域数据以查找丢失的数据（即由于某些链路上的故障检测器），然后根据情况纠正或丢弃数据。然后，数据为：（i）使用指数平滑将其添加到该时间间隔/位置的先前“简档”数据，从而允许保持当前数据值集合。这些文件不会随着时间的推移而增长;（ii）进一步聚合为“趋势文件”，提供高峰期、白天非高峰期等的平均数据值。这些文件随着时间的推移而增长;（iii）丢弃或以二进制格式离线存储，以最大限度地减少存储需求。所有正在处理的数据与相应的配置文件“限制”进行比较;位于这些限制内的数据被接受，而指示异常交通状况（例如由于事故）的外围数据被转移到“离群值”文件中进行单独分析。基于dBASE及其支持图形软件dGE的数据库系统包括各种数据分析选项。提供的分析选项包括：
The primary purpose of the SCOOT (Split Cycle Optimisation Offset Technique) traffic responsive Urban Traffic Control (UTC) system is the optimisation of signal timings in a network to give minimum overall delay. However, in the process of optimisation, SCOOT provides a wealth of traffic information which is potentially useful for a variety of purposes. This study describes an investigation of the data available, its usefulness and potential applications and the development, production and demonstration of a micro-computer based database system for processing, storage and analysis of the data. The traffic data available from SCOOT carried out by Southampton University for the Traffic Operations Division of the Transport and Road Research Laboratory (TRRL) can be obtained at a variety of levels of detail. Geographically this may vary from data for an individual link to aggregated data for a whole region, with potential time aggregation from one second to five minutes or more. More precise data requirements were determined from responses to a questionnaire sent to a sample of Local Authorities, Regional Offices and Policy Divisions of the Department of Transport. The database system operates on an IBM PC (or compatible) microcomputer linked to the SCOOT computer. The system is largely menu-driven and incorporates a number of user-defined options both at installation and for subsequent data processing and analysis. Some key parameters that the user can define at installation are described and guidance on the selection of appropriate input values are included for most parameters, together with default values. Data processing involves receipt by the microcomputer of the 'raw' SCOOT messages, on-line stripping of this data to its minimum size (eg removal of repeated data descriptors) and data aggregation to its user-defined aggregation level. Regional data is scanned for missing data (ie due to faulty detectors on some links) and data is then corrected or discarded as appropriate. The data is then: (i) added to previous 'profile' data for that time interval/location using exponential smoothing, allowing a current set of data values to be maintained. These files do not grow through time; (ii) aggregated further into 'trend files' giving average data values for peak, daytime off-peak, etc. Aggregation is only accepted if sufficient data has been received (as defined at installation). These files grow through time; (iii) discarded or stored off-line in binary format to minimise storage requirements. All data being processed is compared with corresponding profile 'limits'; data lying within these limits is accepted, while outlying data, indicative of abnormal traffic conditions (eg due to an incident) is diverted to an 'outliers' file for separate analysis. A variety of data analysis options are included in the database system, based on dBASE and its supporting graphical software dGE. The analysis options provided include: tabulations of data