Robust Hydraulic Fracture Monitoring (HFM) of Multiple Time Overlapping Events Using a Generalized Discrete Radon Transform

In this work we propose a novel algorithm for multiple-event localization for Hydraulic Fracture Monitoring (HFM) through the exploitation of the sparsity of the observed seismic signal when represented in a basis consisting of space time propagators. We provide explicit construction of these propagators using a forward model for wave propagation which depends non-linearly on the problem parameters - the unknown source location and mechanism of fracture, time and extent of event, and the locations of the receivers. Under fairly general assumptions and an appropriate discretization of these parameters we first build an over-complete dictionary of generalized Radon propagators and assume that the data is well represented as a linear superposition of these propagators. Exploiting this structure we propose sparsity penalized algorithms and workflow for super-resolution extraction of time overlapping multiple seismic events from single well data

Wireless ad-hoc networks: Strategies and Scaling laws for the fixed SNR regime

This paper deals with throughput scaling laws for random ad-hoc wireless networks in a rich scattering environment. We develop schemes to optimize the ratio, $\rho(n)$ of achievable network sum capacity to the sum of the point-to-point capacities of source-destinations pairs operating in isolation. For fixed SNR networks, i.e., where the worst case SNR over the source-destination pairs is fixed independent of $n$, we show that collaborative strategies yield a scaling law of $\rho(n) = {\cal O}(\frac{1}{n^{1/3}})$ in contrast to multi-hop strategies which yield a scaling law of $\rho(n) = {\cal O}(\frac{1}{\sqrt{n}})$. While, networks where worst case SNR goes to zero, do not preclude the possibility of collaboration, multi-hop strategies achieve optimal throughput. The plausible reason is that the gains due to collaboration cannot offset the effect of vanishing receive SNR. This suggests that for fixed SNR networks, a network designer should look for network protocols that exploit collaboration. The fact that most current networks operate in a fixed SNR interference limited environment provides further motivation for considering this regime.Comment: 26 pages single column, submitted to Transactions on Information Theor

Identification of Marketing Capabilities: A study on Indian product based B2B Telecom start-ups

New technology based start-ups play a very important role in developing the economy of a country. In India telecom sector has seen unprecedented growth over the decade and this has led to emergence of several telecom related start-ups. However, product based B2Bstart-ups are still rare and they have to undergo several challenges to stay afloat. Surprisingly not much research work has been undertaken in identifying capabilities among early stage start-ups although the early phase represents a very crucial phase for product based firms and in determines the success or failure for start-ups. Present study explores the inherent marketing capabilities that enable commercialization among such early stage start-ups by adopting a multiple case based inductive methodology with Indian telecom start-ups as our context. We have identified market orientation, positioning and segmentation, selling and after sales services as components of marketing capability of such start-ups. We also identify several idiosyncrasies among telecom start-ups vis-�-vis established firms in the sector. Fina lly we make a case for policy level intervention to promote telecom start-ups in the Indian context.

Opportunity Recognition in High Tech and Regulatory Environment: A study of product based Indian Telecom start-ups

Opportunity recognition forms the first step of entrepreneurship. Off late entrepreneurship research has looked at opportunity recognition from varied lenses with entrepreneurial learning forming the core of most scholarly work. However opportunity recognition in high tech sectors is slightly different due to a high component of knowledge intensiveness inherent in such sectors and has been largely ignored in most work. So, we explore a specific high tech sector in the paper to understand and further the existing concepts within opportunity recognition process. We choose the Indian telecom sector as the context of the study and using an inductive case based approach arrive at conceptual combination as the dominant form of idea generation. The regulatory environment was found to acts as an enabler for the new ideas to flourish. We also bring in the idea of dynamic customization as the driving force behind the venture akin to symbiotic relationship present between organisms in the nature.

Efficient Low Rank Tensor Ring Completion

Using the matrix product state (MPS) representation of the recently proposed tensor ring decompositions, in this paper we propose a tensor completion algorithm, which is an alternating minimization algorithm that alternates over the factors in the MPS representation. This development is motivated in part by the success of matrix completion algorithms that alternate over the (low-rank) factors. In this paper, we propose a spectral initialization for the tensor ring completion algorithm and analyze the computational complexity of the proposed algorithm. We numerically compare it with existing methods that employ a low rank tensor train approximation for data completion and show that our method outperforms the existing ones for a variety of real computer vision settings, and thus demonstrate the improved expressive power of tensor ring as compared to tensor train.Comment: in Proc. ICCV, Oct. 2017. arXiv admin note: text overlap with arXiv:1609.0558