# Efficient and Safe Strategies for Intersection Management: A Review
###### Abstract  
Intersection management is a sophisticated event in the intelligent transportation system due to a variety of behavior for traffic participants. This paper primarily overviews recent studies on the scenes of intersection, aiming at improving the efficiency or guaranteeing the safety when vehicles pass the crossing. These studies are respectively surveyed from the perspectives of efficiency and safety. Firstly, recent contributions to efficiency-oriented, intersection management overviews from four scenes, including congestion avoidance, green light optimized speed advisory (GLOSA), trajectory planning, and emergency vehicle priority preemption control. Furthermore, the studies on intersection collision detection and abnormal information warning are surveyed in the safety category. The corresponding algorithms for velocity and route management presented in the surveyed works are discussed. intersection management; intelligent transportation system; congestion avoidance; green light optimized speed advisory; trajectory planning; intersection collision detection; abnormal vehicle warning +
Footnote †: journal: _Sensors_  
0000-0001-9999-4000-3399-3399-3999  
step to achieve autonomous driving and intelligent transportation. When applying V2X vehicle networking to ITS, the system needs to send status information (position, speed, direction, etc.) of the vehicle collected by radio frequency identification (RFID), sensors, etc. installed on the vehicle to surrounding vehicles accurately through vehicles and roadside units (RSU), vehicles, and vehicles along with other communication methods [5] in real time. After information is gathered, an effective message is extracted through data analysis and processing. Appropriate trajectories and speeds are calculated using corresponding algorithms, providing intelligent decision-making basis for vehicle running. The scenes are divided into two board classifications: Safety and efficiency. The idea of this paper is shown in Figure 1. When approaching the intersection, the algorithms of collision detection and abnormal information warning start working to detect the hidden danger, guaranteeing cars safely passing the intersection. Two applications mentioned above are devoted to doing it. Sensors will detect whether the congestion exists and then the system uses algorithms to avoid it. After RSU sends the information about a traffic light, Green Light Optimized Speed Advisory (GLOSA) calculates the speed of passing the intersection without stopping. The metrics related to the speed advisory algorithms are given below. In order to find an applicable route, trajectory planning algorithms play an important role and give suitable routes. Combining methods of GLOSA and trajectory planning, we can obtain the route and speed of passing the intersection, which provides the driver with a better driving experience. To appreciate the particularity of emergency vehicles, the paper provides three methods on how to assist ambulances, police cars, and so on to cross an intersection promptly. Based on these techniques, a new method is proposed to help a vehicle safely and quickly pass the intersection. We compare the main algorithms and choose relatively good methods in each scene. Vision-based detection is more cheap and has a wider range and its development is more mature, it is useful to use this this way to help us detect the barriers. Abnormal vehicle warning, control loss warning, and hazardous location warning are also finished with the assistance of a camera. VANET combined with image processing can be useful in good road conditions to avoid congestion. The part of GLOSA focuses on metrics for evaluating algorithms. In addition, LOSB-F is chosen to assist in passing the intersection without stopping. For trajectory planning, the Q-learning is selected for the route. The final part is a special circumstance. Both the traffic light and vehicles will receive messages to yield to it and help the emergency vehicles pass the intersection.