This study incorporates artificial neural network (ANN) modeling to design an intelligent road signboard that uses internet of things (IoT) technology to assign the speed limit on interurban highways. The appropriate speed limit must be determined by traffic police experts based on weather conditions and times of the day. Here, an intelligent IoT-based signboard is proposed to announce speed limits on roadways considering some effective parameters, such as temperature, humidity, time, and light. The signboard receives environmental data through its sensors and uses artificial neural networks to compute the speed limit. A feed-forward neural network (FFNN) is provided as the most reliable model. A hybrid training method based on gray wolf optimization and Bayesian regularization is also developed to enhance model performance. The proposed hybrid model converges with an error of less than 3.0% to expert opinion.The model equations are extracted for use in a microcontroller that calculates a safe speed limit based on weather conditions. Additionally, the underlying IoT technology has enabled the police station to remotely monitor and control the developed system. Experimental results demonstrate the reliability of the designed signboard. In all experimental cases, the computed speed limits were in coincidence with the expert's estimations.
K E Y W O R D Sartificial neural networks, intelligent signboard, interurban ways, IoT technology, road traffic accidents, speed limit
INTRODUCTIONSurprisingly prevalent on a global scale, road traffic accidents constitute one of the leading causes of human mortality and chronic injury. A fatal traffic collision occurs every 50 s, while road injuries occur every 2 s on average. 1,2 Traffic accident casualties account for 30% to 70% of orthopedic beds in hospitals in developing countries. According to the World Health Organization (WHO), nearly 1.3 million people die annually on the world's roadways, while 20-50 million are affected by severe traumas. Unless appropriate measures are taken, the WHO predicts that traffic accidents will be the seventh leading cause of death by 2030. 3 The majority of victims require expensive, long-term care. Road accidents waste 1%-3% of the gross domestic product in many countries, resulting in substantial economic losses irrespective of the grief and suffering. 4 As a result, one of the most critical concerns in all countries is preventing the repercussions of traffic accidents.Distracted driving, exceeding the speed limit, drunk driving, drug use, rain, snow, car defects, teenage drivers, tire blowouts, and night driving are the most common causes of car accidents. 5,6 Several causes of road accidents may be effectively prevented; however, this requires continuous efforts to develop new methods and programs that can improve road traffic safety.