جستجوی مقالات مرتبط با کلیدواژه « Traffic Signal » در نشریات گروه « فنی و مهندسی »

In this article, a new design for traffic signals is presented in such a way that the consumption of each light with the same level of intensity is greatly reduced. Today, with the development of urbanization, energy consumption has also increased. Building new power plants to provide energy is expensive and increases air pollution. Accordingly, that the only possible solution is to use new technologies in the field of energy consumers in such a way that their consumption with the same efficiency will be significantly reduced. At present, traffic signals have an average power of 10 watts. This amount means that the lighting consumption of an intersection is equal to 320 watts on average. Also, the high consumption of analog control systems should be added to this amount. In this article, the design of super low consumption traffic signals has been produced. Their power is 1.5 watts on average. The lights of the previous intersection consume 48 watt hours of energy. With the new lights, the energy consumption is reduced by 85%, with the consumption of the digital control device (8 watts) and assuming that every day has 12 hours of lighting, by using two 60 watts solar panels, the intersection can be independent of city electricity.

In order to reduce the adverse effects of intersections, intelligent systems and the alignment of lights can be used. The BITS system is a localized version of SCATS and SCOOT systems. The aim of this study was to evaluate of BITS system on traffic and environmental variables. The system was evaluated in both cases of coordinated and isolated signals. Traffic variables include line length, delay time, stop time, travel time, and average speed. Environmental variables include fuel consumption, air pollution caused by carbon monoxide, hydrocarbons, and nitrogen oxides, and noise pollution. Prescheduled, intelligent, and coordinated control systems were compared by collecting field data on the traffic flow rate, travel time, and air and noise pollution and simulation in AIMSUN software in three four-way and two three-way intersections in Yazd, Iran. The results showed that all variables were significantly improved in the isolated intelligent control system compared to the isolated prescheduled control system, and the coordinated prescheduled control system performed better than the isolated prescheduled control system. The isolated intelligent control system showed the best traffic and environmental performance. In addition, line length and stop time were the most affected. Compared to other variables, these two could mostly be measured through drivers’ perceptions. According to the above, using BITS intelligent traffic signals and coordinating nearby intersections – the green wave in successive intersections – can prevent the waste of time and national resources. More immediate effects are reduced air and noise pollution, and reduced delay.

Phenomena in the real world are grouped into two categories: static and dynamic. The static phenomena don’t change with variation of the time but the dynamic phenomenon will do it so. These changes may be occurred in the phenomena property like spatial or geometry. Traffic is a Spatio-Temporal phenomenon because its properties which are referring to some locations on the earth will change in respect to the time variation. Today, due to the development of technology, the management capability of the spatial-temporal phenomenon has been provided in a Temporal Geospatial Information System (TGIS). The objective of this research is study of using TGIS for controlling and coordinating of traffic signals. For this purpose, first, parameters and components for determining traffic condition and coordinating traffic signals are collected. Then based on these data, the structure of the traffic data is determined for entering into a database. This structure determined in such a way that the traffic condition is introduced to the system based on the type of existing traffic behavior. In this study, the dynamic data along with spatial data of street path (static data) are stored and structured based on relational model and Time Stamping Spatial Objects model. With performing relation between these data the instant variations of the traffic condition is determined. Based on these variations the traffic parameters and offset between different intersections are computed and then based on this information the schedule of traffic signals will be implemented with a singular or network method.