Vehicles authentication, the integrity of messages exchanged, and privacy-preserving are essential features in vehicular ad hoc network (VANETs) security. Most of the previously proposed VANETs security solutions do not sufficiently satisfy the security and efficiency requirements. Besides, most of those solutions are heavily dependent on the system key and long-term sensitive data stored in an ideal tamperproof device, which may not be practical or ideal for resource-constrained onboard units (), especially in the case of an unexpected cloning or physical attack. Therefore, a robust authentication solution should consider those security issues and the nature of resource-constrained nodes. To satisfy all these requirements, we propose a lightweight multi-factor authentication and privacy-preserving security solution for VANETs. It employs a combination of physically unclonable functions () and one-time dynamic pseudo-identities as authentication factors. Furthermore, it eliminates the heavy dependency on the system key by decentralising the wide precinct of the certificate authority () into regional domains and achieves robust control of domains keys. A detailed analysis demonstrates that our scheme efficiently meets the VANETs security requirements, and offers more suitable communication and computation costs and features than existing schemes.

Detection of mitotic tumor cells per tissue area is one of the critical markers of breast cancer prognosis. The aim of this paper is to develop a method for the automatic detection of mitotic figures from breast cancer histological slides using a partially supervised deep learning framework. Unlike the previous literature, which has focused on solving the problem of mitosis detection in the weakly annotated datasets using centroid pixel labels (weak labels) only without taking advantage of the available pixel-level labels (strong labels) of other datasets, in this paper, we design a novel partially supervised framework based on two parallel deep fully convolutional networks. One of them is trained using weak labels and the other is trained using strong labels, together with a weight transfer function. In the detection phase, we fuse the segmentation maps produced by the two networks to obtain the final mitosis detections. Our system exploits the available large sets of mitosis detection samples with mitosis centroid annotation, such as the 2014 ICPR dataset and the AMIDA13 dataset, and only a small set of samples with the annotation of all mitosis pixels, such as the 2012 ICPR dataset, to perform a more accurate mitosis detection on weakly labeled data. This enables us to outperform all previous mitosis detection systems by achieving F-scores of 0.575 and 0.698 on the 2014 ICPR dataset and the AMIDA13 dataset respectively.

The basic idea behind the vehicular ad-hoc network (VANET) is the exchange of traffic information between vehicles and the surrounding environment to offer a better driving experience. Privacy and security are the main concerns for meeting the safety aims of the VANET system. In this paper, we analyse recent VANET schemes that utilise a group authentication technique and found important vulnerabilities in terms of driving safety. These systems also suffer from vulnerabilities in terms of management efficiency and computational complexity. To defeat these problems, we propose a lightweight scheme, SD2PA, based on a general hash function for VANET. The proposed scheme overcomes the non-safe driving problem that resulted from the critical driving area. Moreover, the vehicle authentication is only done once by the VANET system administrator during the vehicle’s moving, so the authentication redundancy for the entire system is reduced and system management efficiency is enhanced. The SD2PA scheme also provides anonymity to protect the vehicle’s privacy, unless an important action needs to be taken against a malicious vehicle. A deep computational cost and communicational overhead analysis indicates that SD2PA is better than related schemes, as well as efficiently meeting VANET’s security and privacy needs.