This paper presents a wearable obstacle avoidance system for blind people to navigate safely using cane and eyeglass methods. In cane method, an ultrasonic sensor is placed in cane which detects the obstacle in the ground level. In eyeglass method, an ultrasonic sensor is used which detects obstacle above the head up to certain angle. The information obtained is informed to users using audio messages and also by sense of feel as vibration in case of born both deaf and blind. These algorithms are implemented using MP Lab and Proteus tools.

Identification of landmark nodes in complex networks has been of great interest but the parameters based on which these nodes are selected have been different in different cases. We believe that Landmarks are those nodes that occur most frequently while we explore or navigate a network. We propose 2 methods and efficient algorithms to identify these nodes. We identify these nodes using centrality measures and random walks. We show that the methods proposed are both, effective and efficient. Our approach has been extensively evaluated using synthetic environments. The results obtained verify its robustness along with its applicability.

No abstract

The current paper is an investigation towards understanding the navigational performance of humans on a network when the 'landmark' nodes are blocked. We observe that humans learn to cope up, despite the continued introduction of blockages in the network. The experiment proposed involves the task of navigating on a word network based on a puzzle called the wordmorph. We introduce blockages in the network and report an incremental improvement in performance with respect to time. We explain this phenomenon by analyzing the evolution of the knowledge in the human participants of the underlying network as more and more landmarks are removed. We hypothesize that humans learn the bare essentials to navigate unless we introduce blockages in the network which would whence enforce upon them the need to explore newer ways of navigating. We draw a parallel to human problem solving and postulate that obstacles are catalysts for humans to innovate techniques to solve a restricted variant of a familiar problem.

No abstract