Glossary
| ID |
Term |
Definition |
Source of Definition |
| Alternative |
A specific set of specific operational practices or transportation system improvements represented and evaluated within a microsimulation analysis. The impact of each alternative is compared to other alternatives in the analysis based on key performance measures to inform transportation management decisions. |
TAT Volume III Update |
| Computational Platforms |
A computing platform is, in the most general sense, whatever a pre-existing piece of computer software or code object is designed to run within, obeying its constraints, and making use of its facilities. The term computing platform can refer to different abstraction levels, including a certain hardware architecture, an operating system (OS), and runtime libraries. In this document, the term computational platform is intended to describe the computing system used by a transportation analyst when conducting an analytic project—the platform on which the transportation analysis software runs. |
Wikipedia |
| Connected vehicles |
Connected vehicles interact with each other (V2V), the roadside (V2I), and beyond (V2X) via wireless communications. |
ITS Strategic Plan |
| Crowdsourcing |
The practice of obtaining needed services, ideas, or content by soliciting contributions from a large group of people and especially from the online community rather than from traditional employees or suppliers. |
Merriam Webster |
| Dedicated Short-Range Communication (DSRC) |
DSRC is a two-way short- to- medium-range wireless communications capability that permits very high data transmission critical in communications-based active safety applications. |
ITS Strategic Plan |
| Intermodal |
Involving more than one mode of transport during a single journey, e.g., a commuter drives to a bus stop; the bus transports him/her to a subway station for the remainder of the trip; a freight container travels by ship to a port where it is transferred to rail, and then to truck at the destination area. |
ITS JPO |
| Internet of Things |
A concept that built infrastructure is linked and dynamic, often displaying intelligence via integrated sensors and adaptive controls. |
ITS JPO |
| Interoperability |
The ability of two or more systems or components to exchange information and to use the information that has been exchanged. |
ITS Strategic Plan |
| ITS Project |
ITS Project means any project that in whole or in part funds the acquisition of technologies or systems of technologies that provide or significantly contribute to the provision of one or more ITS user services as defined in the National ITS Architecture. |
Rule 940 |
| Macroscopic Simulation |
Simulation based on deterministic relationships of the flow, speed, and density of the traffic stream; simulation takes place on a section-by-section basis. |
ITS JPO |
| Metadata |
A set of data that describes and gives information about other data. |
Oxford Dictionary |
| Metropolitan Planning Organization (MPO) |
A federally mandated and federally funded transportation policy-making organization in the U.S. that is made up of representatives from local government and governmental transportation authorities |
ITS Strategic Plan |
| Microscopic Simulation |
Simulate movement of individual vehicles based on car-following and lane-changing theories; vehicle enter a network using statistical distribution of arrivals and are tracked through the network. |
ITS JPO |
| Mobility |
The ease with which members of a society move using transportation infrastructure such as roadways, bridges, pedestrian walkways, bike lanes, rail, etc. |
ITS Strategic Plan |
| Model Calibration (also called Analysis Tool Calibration) |
Model calibration is the process of systematically adjusting model parameters so that the model is able to reproduce the observed traffic conditions. |
Module 2 |
| Multimodal |
Describes more than one mode of transport, or a technology application that affects more than one mode of transportation. |
ITS JPO |
| Operational Conditions |
A set of analogous conditions within the transportation system based on variation in travel demand, incident patterns, prevailing weather, and other factors that create similar system performance. |
TAT Volume III Update |
| Outlier Data |
An observation that lies outside the overall pattern of a distribution. |
 |
| Performance Measures |
Performance measures support objective and serve as a basis for comparing alternative improvement strategies (investment and policy approaches) and for tracking results over time. |
ITS JPO Fact Sheet |
| Probe Data |
Data generated by vehicles about their current position, motion, and time stamp. Vehicle probe data may be generated by devices integrated into the vehicle itself or provided by nomadic devices brought into the vehicles. |
ITS Probe Data Fact Sheet |
| Roadside Unit (RSU) |
A connected device that is only allowed to operate from a fixed position (which may in fact be a permanent installation or from temporary equipment brought on-site for a period of time associated with an incident, road construction, or other event). Some RSUs may have connectivity to other nodes or the Internet. Also referred to as Roadside Equipment (RSE). |
ITS Strategic Plan |
| Scenario |
A scenario describes one way that a system is or is envisaged to be used in the context of activity in a defined timeframe. The timeframe for a scenario could be (for example) a single transaction; a business operation; a day or other period; or the whole operational life of a system. Similarly, the scope of a scenario could be (for example) a single system or piece of equipment; an equipped team or department; or an entire organization. In this document, a scenario refers to a specific combination of a distinct operational condition and a particular alternative operational strategy that generates a resulting pattern of system performance (either in reality or in a modeled environment). |
Wikipedia |
| System |
A combination of interacting elements organized to achieve one or more stated purposes. |
INCOSE |
| Systems Engineering |
Systems Engineering is an interdisciplinary approach and means to enable the realization of successful systems. It focuses on defining customer needs and required functionality early in the development cycle, documenting requirements, then proceeding with design synthesis and system validation while considering the complete problem. |
INCOSE |
