Joint source and relay optimization for interference MIMO relay networks

This paper considers multiple-input multiple-output (MIMO) relay communication in multi-cellular (interference) systems in which MIMO source-destination pairs communicate simultaneously. It is assumed that due to severe attenuation and/or shadowing effects, communication links can be established only with the aid of a relay node. The aim is to minimize the maximal mean-square-error (MSE) among all the receiving nodes under constrained source and relay transmit powers. Both one- and two-way amplify-and-forward (AF) relaying mechanisms are considered. Since the exactly optimal solution for this practically appealing problem is intractable, we first propose optimizing the source, relay, and receiver matrices in an alternating fashion. Then we contrive a simplified semidefinite programming (SDP) solution based on the error covariance matrix decomposition technique, avoiding the high complexity of the iterative process. Numerical results reveal the effectiveness of the proposed schemes

ERP performance triangle : exploring the interplay between benefits realisation management, project governance, and project success

The current study aim to explore the trio interplay ERP’s Benefits realisation, project governance, and project success in Oil corporations in Gulf. Using a set of 12 qualitative semi-structured interviews, an interpretative study has addressed senior management’s perspective in the Kuwait Petroleum Corporation. At the corporate level, our findings show that managing ERP project benefits enhances corporate strategic goals and overall success. At the project level, we have revealed a relationship between benefits realisation, decision making, bottom-up governance between project managers and project members

Energy harvesting enabled MIMO relaying through power splitting

This paper considers a multiple-input multiple-output (MIMO) relay system with an energy harvesting relay node powered by harvesting energy from the source node using power splitting (PS). The rate maximization problem subject to power constraints at both the source and relay nodes is considered for two different scenarios. Firstly, the relay matrix and PS ratio are jointly optimized with uniform source precoding and then in the second scenario the source covariance is optimized as well. Iterative approaches and dual decomposition are proposed based on the structures of the optimal relay and source covariance matrices for the scenarios

A domain equation for refinement of partial systems

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Static Analysis of Parity Games: Alternating Reachability Under Parity

It is well understood that solving parity games is equivalent, up to polynomial time, to model checking of the modal mu-calculus. It is a long-standing open problem whether solving parity games (or model checking modal mu-calculus formulas) can be done in polynomial time. A recent approach to studying this problem has been the design of partial solvers, algorithms that run in polynomial time and that may only solve parts of a parity game. Although it was shown that such partial solvers can completely solve many practical benchmarks, the design of such partial solvers was somewhat ad hoc, limiting a deeper understanding of the potential of that approach. We here mean to provide such robust foundations for deeper analysis through a new form of game, alternating reachability under parity. We prove the determinacy of these games and use this determinacy to define, for each player, a monotone fixed point over an ordered domain of height linear in the size of the parity game such that all nodes in its greatest fixed point are won by said player in the parity game. We show, through theoretical and experimental work, that such greatest fixed points and their computation leads to partial solvers that run in polynomial time. These partial solvers are based on established principles of static analysis and are more effective than partial solvers studied in extant work

Truth-Telling Mechanism for Two-Way Relay Selection for Secrecy Communications With Energy-Harvesting Revenue

This paper brings the novel idea of paying the utility to the winning agents in terms of some physical entity in cooperative communications. Our setting is a secret two-way communication channel where two transmitters exchange information in the presence of an eavesdropper. The relays are selected from a set of interested parties, such that the secrecy sum rate is maximized. In return, the selected relay nodes' energy harvesting requirements will be fulfilled up to a certain threshold through their own payoff so that they have the natural incentive to be selected and involved in the communication. However, relays may exaggerate their private information in order to improve their chance to be selected. Our objective is to develop a mechanism for relay selection that enforces them to reveal the truth since otherwise they may be penalized. We also propose a joint cooperative relay beamforming and transmit power optimization scheme based on an alternating optimization approach. Note that the problem is highly non-convex, since the objective function appears as a product of three correlated Rayleigh quotients. While a common practice in the existing literature is to optimize the relay beamforming vector for given transmit power via rank relaxation, we propose a second-order cone programming-based approach in this paper, which requires a significantly lower computational task. The performance of the incentive control mechanism and the optimization algorithm has bee

Mobile financial services at the base of the pyramid : a systemic view for cross-sector governance and embedded innovation

Mobile financial services is one of the uprising movements to bank the unbanked by integrating philanthropic and business approaches for financial inclusion. In this paper, we address how a systemic view help integrate the Philanthropic Initiatives (PI) and the Commercial Initiatives (CI) to get a sustainable impact on the unbanked micro-entrepreneurs. However, each approach has pros and cons as they go along the stages of design, deployment, and sustainability. Using the soft system thinking we theorise the Base of the Pyramid (BoP) as a business system to mix-up the relatively high start-up capabilities of the PI with the relatively sustainable impact of CI. Our mobile money case shows that donors, local private enterprises, and multinational corporations follow the BoP strategy to develop an online grid that offers a reconciled balanced scorecard for economic returns, social benefits and local impact. Such a strategy guarantees flexible, long-term investments and facilitate developing innovative financial services