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Mobile Visualization Design: An Ideation Method to Try
Published in Bongshin Lee, Raimund Dachselt, Petra Isenberg, Eun Kyoung Choe, Mobile Data Visualization, 2021
Sheelagh Carpendale, Petra Isenberg, Charles Perin, Tanja Blascheck, Foroozan Daneshzand, Alaul Islam, Katherine Currier, Peter Buk, Victor Cheung, Lien Quach, Laton Vermette
The activity for this example is bike commuting. With this activity comes constraints that led to several adjustments in the original methodology. First, commuting by bike is usually a single-person activity. Although in this example there was a child present, the child was in a trailer at the back, therefore, this was a one-person ideation process. I set an alarm on my watch to get a notification at a time I knew I would be commuting (once in the morning and once in the evening). Upon being notified, I “visualized” in my head a mobile visualization that I would find handy right at that time. Finally, I sketched the idea once I arrived at work / at home with some rough notes. The first ideation was triggered at one of these frustrating times while waiting at a red light. When notified by my alarm, I was thinking about the green wave traffic lights popular in northern Europe. The idea behind green wave traffic [18] is to synchronize traffic lights so that if one maintains a constant speed they will get only green lights. For bikes, the target speed is usually between 15 and 20 km/h. This train of thought made me think of two simple designs, aimed at providing the same information to cyclists. The first design uses a series of LEDs while the second one is more continuous and uses the metaphor of a level bubble. Both ideas are designed to fit on the frame of the bike, always visible when cycling, not requiring to pay too much attention, and most importantly being in line of sight of the cyclist. These designs assume close connection to a phone for computation and network access.
Economic analysis of mobility improvements
Published in Zongzhi Li, Transportation Asset Management, 2018
Older hardware and software can be updated to more efficient systems with improved vehicle sensing technologies and communications. The latest traffic signal controllers have more flexibility in signal timing and allow more adaptive, traffic-responsive control of signals. Newer control equipment also offers an improved interface with area-wide signal control systems, which agency staff can use to monitor and adjust signal timing in real time. Improving signal timing and coordination involves optimizing timing plans to optimize the flow of traffic by giving the main traffic flows green time when they need it most. Coordinating signals can create a green wave with minimal stops or slowdowns as traffic moves between signalized intersections along a street. Signals are interconnected and linked in time to ensure the integrity of the timing plan. State-of-the-art signal management systems facilitate the exchange of traffic flow information between signals, allowing for automated, real-time signal coordination. Technological advances now allow signals both to learn from historical patterns and to incorporate real-time data. As traffic patterns shift, signals that are no longer needed may be removed to reduce unnecessary delay and stops at an intersection. Potential candidates for signal improvements are arterial streets and major activity centers and central business districts.
The technology of bus and coach systems
Published in Peter White, Public Transport, 2017
Such priority may be given either at junctions which are individually controlled (usually through MOVA software), or those within linked networks. Urban traffic control (UTC) schemes have been introduced in many cities, in which optimal use is made of an entire network – in terms of capacity, and/or minimising delay – through central computer control. A common feature is the provision of a ‘green wave’ in which a platoon of vehicles is able to experience a green phase on most signalled junctions it crosses, by the green phases at each junction being offset to allow for the average speed of vehicles in the platoon. However, running times of buses between junctions may be longer than for cars owing to the presence of intermediate stops and lower acceleration. Buses may thus fail to benefit, or even hit more red phases than before. Traditional fixed-time linking systems such as ‘Transyt’ may be modified to incorporate bus characteristics. More recent systems such as ‘SCOOT’ (Split Cycle Offset Optimisation Technique) have also been adapted to allow for buses in addition to giving overall capacity gains for traffic as a whole of about 10 per cent. However, the bus priority tends to be most beneficial at intermediate traffic volumes rather than saturation level. A review of options available at traffic-light-controlled junctions is provided by Hounsell et al.(2004).
Examining the factors influencing the injury severity of crashes on arterials with signal coordination
Published in Journal of Transportation Safety & Security, 2020
Guopeng Zhang, Xinguo Jiang, Yingfei Fan, Wenbo Fan, Teng Meng
Urban arterials play a critical role in carrying most of the vehicle traffic on the roadway network. Although they are typically associated with more severe injury crashes than local roads due to relatively higher traveling speed. Thus, the operation of arterials gains special attention by traffic researchers and engineers in terms of efficiency (Zhang, Song, Tang, & Wang, 2016) and safety (Wang et al., 2015; Wang et al., 2016; Li & Wang, 2017). Traffic signals are usually installed at intersections along arterials to ensure orderly operations. Coordinating the traffic signals on arterials has witnessed popularity in urban traffic management and control in the past decades. It is a technique of signal timing that synchronizes multiple signals at consecutive intersections to generate “green waves” among them for a group of vehicles to travel through with fewer or no stops. A large number of applications have demonstrated effectiveness of signal coordination in terms of improving vehicle operational efficiency (Papageorgiou, Diakaki, Dinopoulou, Kotsialos, & Wang, 2003).
Microscopic evaluation of traffic safety at signal coordinated intersections: A before–after study
Published in Traffic Injury Prevention, 2018
Guopeng Zhang, Wenbo Fan, Teng Meng, Xinguo Jiang, Guangrong Chen
Recent decades have seen the great popularity of signal coordination in urban traffic control. Synchronizing multiple signalized intersections along an arterial can greatly improve the operational efficiency of vehicular traffic movements. Specifically, the coordination of several signalized intersections generates a “green wave,” allowing the platooning vehicles to travel along the arterial with minimal or no stops. A large body of previous studies has demonstrated that compared to the isolated signal control, signal coordination poses a number of advantages such as increasing operational efficiency (Rakha et al. 2000) and reducing vehicular emissions (De Coensel et al. 2012; Madireddy et al. 2011; Unal et al. 2003).
Coordinated control model for arterials with asymmetric traffic
Published in Journal of Intelligent Transportation Systems, 2022
Under unsaturated traffic conditions, road capacity is greater than traffic demand. Green wave control can optimize the signal timing to reduce vehicle delay. In this paper, variable-bandwidth optimization is adopted, and 0–1 binary variables are introduced for constraint relaxation. By interrupting the green waves of some segments, the feasible region is expanded to obtain the arterial’s overall optimal green wave bandwidth (Yao et al., 2019).