Further, the risk of an authentication error is typically borne by multiple parties, including the implementing organization, organizations that rely on the authentication decision, and the subscriber. Because the subscriber may be exposed to additional risk when an organization accepts a RESTRICTED authenticator and that the subscriber may have a limited understanding of and ability to control that risk, the CSP SHALL:
As biometrics are only permitted as a second factor for multi-factor authentication, usability considerations for intermittent events with the primary factor still apply. Intermittent events with biometrics use include, but are not limited to, the following, which may affect recognition accuracy:
Currently, many transportation agencies are collecting pavement image data in a routinely and periodic manner. For example, most of transportation agencies collect pavement data annually, while some of them collect pavement data every 6 months. As a result, historical crack images can be obtained by several crack data collections. The pavement cracks will not grow substantially in a short period of time. Hence, the historical crack data can be utilized to enhance current crack analysis. To achieve this goal, an important task is to establish the correspondence between historical and current crack images, which is also called localization. Therefore, this paper proposed a method that using historical data as reference for current crack analysis. Especially, the proposed method aim to address the localization problem by using a multi-scale strategy. Contributions of this paper are summarized as follow: 1) The authors proposed a method that using historical crack data as the reference for pavement crack analysis, which can greatly enhance the performance of pavement crack analysis; 2) The authors proposed a multi-scale localization strategy to match historical crack image with current crack image. The multi-scale localization method consists of GPS-based coarse localization, image-level localization and finally pixel-level localization; 3) By referring to historical crack data, the authors proposed a novel approach, called RGM, it can detect the condition change of pavement cracks easily. The condition change of pavement crack is especially important for pavement treatment strategies.
where k is a threshold distance to select the candidate historical crack data. It decides that the ith historical crack data is close enough to the jth query crack data. dij is the distance between ith historical crack data and jth query crack data. In practice, according to the accuracy of GPS localization, the threshold distance is heuristically set to 10 meter. After GPS-based coarse localization, a limited number of candidate historical crack images, which satisfies Eq (2), are obtained.
In order to illustrate the multi-scale localization, the authors demonstrated the number of local feature point pairs between query crack image and each candidate historical crack image. The local feature point pairs are illustrated in Fig 9A. The local feature point pairs increase with the distance that between query crack image and historical crack image decrease. It can be seen in Fig 9A. The number of local feature point pairs for query crack image and No.9 historical crack image is 117. The number of local feature point pairs for query crack image and No.10 historical crack image is 54. The former has more local feature point pairs comparing with the latter. By this way, we compared the number of local feature point pairs between query image and each historical image. As illustrated in Fig 9B, No.9 candidate historical crack image approximates most to query crack image, which confirm to the ground truth. 076b4e4f54