Previous analysis of collision avoidance in ad hoc networks with hidden terminals has focused on senderinitiated schemes, like the IEEE 802.11 distributed coordination function. This paper presents analytical modeling of receiver-initiated collision avoidance schemes in multi-hop ad hoc networks. Our analysis shows that receiver-initiated schemes can offer substantial improvements over senderin...

Previous analysis of collision avoidance in ad hoc networks with hidden terminals has focused on senderinitiated schemes, like the IEEE 802.11 distributed coordination function. This paper presents analytical modeling of receiver-initiated collision avoidance schemes in multi-hop ad hoc networks. Our analysis shows that receiver-initiated schemes can offer substantial improvements over senderin...

According to the National Highway Traffic Safety Administration (NHTSA), more than 43% of all fatal accidents reported in 2001 involved a lane or road departure. There are a number of systems on the market that monitor driver lane position or use radar technology to track the position of other drivers. The majority of these systems and available research focuses on the prevention of longitudina...

With the development of space science and technology, on-orbit module replacement technology has been more and more attention. Accordance with the requirements of on-orbit spacecraft module replacement, this paper designs the flexible swap device, and analyses the working principle of the insert-pull process. Using Pro/E, the parametric geometry model is established, whose dynamics simulation a...

The main contributions of this paper are two-fold. Firstly, we present a novel direction in the cryptanalysis of the cryptographic hash function SHA-1. Our work builds on previous cryptanalytic efforts on SHA-1 based on combinations of local collisions. Due to dependencies, previous approaches used heuristic corrections when combining the success probabilities and message conditions of the indi...

Although SHA-1 has been theoretically broken for some time now, the task of finding a practical collision is yet to be completed. Using some new approaches to differential analysis, we were able to find a new differential path which can be used in a collision attack with complexity of O(2). This is currently the lowest complexity attack on SHA-1.

In this study, the problem of navigation in dynamic and unknown environment is investigated and a navigation method based on force field approach is suggested. It is assumed that the robot performs navigation in...

This paper provides an updated efficiency analysis of the LightForce space debris collision avoidance scheme. LightForce aims to prevent collisions on warning by utilizing photon pressure from ground based, commercial off the shelf lasers. Past research has shown that a few ground-based systems consisting of 10 kW class lasers directed by 1.5 m telescopes with adaptive optics could lower the ex...