Tejpalsingh Siledar, Swaroop Nath, Sankara Muddu, Rupasai Rangaraju, Swaprava Nath, Pushpak Bhattacharyya, Suman Banerjee, Amey Patil, Sudhanshu Singh, Muthusamy Chelliah, Nikesh Garera. Proceedings of the 62nd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers). 2024.

One of the prevalent method to achieve clock synchronization in star topology based wireless network, is by periodic transmission of a “Beacon” message from the controller. Using this message other nodes locate the start of the time frame established by the controller. This technique has not been energy efficient in case of low duty cycle applications, where the nodes have to receive the Beacon at the start of every frame even when they don't have any data to transmit. Few of existing works solve this problem by introducing a larger fixed size guard time between the transmission slots allocated to the devices. This allows the devices to skip multiple Beacons and still transmit in their allocated time slot without any collision. In such methods amount of bandwidth which remain unutilized due to fixed guard time becomes a considerably large fraction of the total available bandwidth. In this paper, we propose a novel technique to allow the nodes to skip the Beacon for certain number of frames by introducing the concept called Variable Guard Time (VGT). The number of frames that a node can remain synchronized with the coordinator without receiving the Beacon depends upon the number of Guard Slots allocated to it. This is decided based upon factors like the node's energy saving requirement, the actual clock drift rate between the devices and the available bandwidth. Simulation results show that, in terms of bandwidth utilization, the proposed idea of VGT outperforms the traditional approach of fixed guard time scheme.

One of the distinguishing features of the services industry is the high emphasis on people interacting with other people and serving customers rather than transforming physical goods like in the traditional manufacturing processes. It is evident that analysis of such interactions is an essential aspect of designing effective and efficient services delivery. In this work we focus on learning individual and team behavior of different people or agents of a service organization by studying the patterns and outcomes of historical interactions. For each past interaction, we assume that only the list of participants and an outcome indicating the overall effectiveness of the interaction are known. Note that this offers limited information on the mutual (pairwise) compatibility of different participants. We develop the notion of service interaction networks which is an abstraction of the historical data and allows one to cast practical problems in a formal setting. We identify the unique characteristics of analyzing service interaction networks when compared to traditional analyses considered in social network analysis and establish a need for new modeling and algorithmic techniques for such networks. On the algorithmic front, we develop new algorithms to infer attributes of agents individually and in team settings. Our first algorithm is based on a novel modification to the eigen-vector based centrality for ranking the agents and the second algorithm is an iterative update technique that can be applied for subsets of agents as well. One of the challenges of conducting research in this setting is the sensitive and proprietary nature of the data. Therefore, there is a need for a realistic simulator for studying service interaction networks. We present the initial version of our simulator that is geared to capture several characteristics of service interaction networks that arise in real-life.