The mission of reducing the number and severity of traffic accidents becomes the dominant target of road traffic safety management worldwide. The main objective of this work is to analyze traffic accidents in temporal and spatial frameworks in the capital city Amman and identify hotspot zones in the study area. Several statistical analyses are conducted using SQL to give insight into the temporal distribution of accidents and to identify the most revealing accidents based on several attributes such as the year of accidents, the severity of accidents, road type, and lighting environment which enables the authors to do further investigations on the more frequent accidents. GIS-based statistical and spatial analysis tools are utilized to examine the spatial pattern of accident distribution in the study area for three successive years, hotspots are identified for clusters of high concentrations. The Nearest Neighbor Index (NNI) is used to analyze the pattern of traffic accident distribution based on selective parameters. This was followed by identifying hotspot zones for regions that showed clustering using the optimal hotspot analysis tool. Experimental results showed clustering for all tested groups, and thus hotspots were detected for these accidents in the study area. The importance of this work is in providing a spatial understanding of accident distribution in the capital city of Amman which can help policymakers of road safety setting out efficient strategies for traffic safety management and find optimal solutions as required for factors causing such accidents.

Abstract:A new method of forward digital signatures is proposed in this paper. All of the previous forward digital signatures depend on changing the private key periodically but they keep the public key. The proposed system will change both private keys and public keys that can be generated only by authorized users to enhance the authenticity of users. Another important proposal is that the expiration of that public key depends on the length of the document so the sender must compute the expired time of his/her document depending on its length. This method also can be used to change the private key depending on the expired date of the document but the public key is still fixed. In order to make this digital signature more efficient, the system must change the private keys in terms of their critical times that indicate the period of exposure of the keys by different attacks types. So the ability to change these keys do not depend on fixed periods as in most forward digital signatures but also depend on these critical times and the entropy of the information of the keys.