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Operations Research, Systems Engineering and Industrial Engineering Commons

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Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

Joint User Grouping And Linear Virtual Beamforming: Complexity, Algorithms And Approximation Bounds, Mingyi Hong, Zi Xu, Meisam Razaviyayn, Zhi-Quan Luo Oct 2013

Joint User Grouping And Linear Virtual Beamforming: Complexity, Algorithms And Approximation Bounds, Mingyi Hong, Zi Xu, Meisam Razaviyayn, Zhi-Quan Luo

Mingyi Hong

In a wireless system with a large number of distributed nodes, the quality of communication can be greatly improved by pooling the nodes to perform joint transmission/reception. In this paper, we consider the problem of optimally selecting a subset of nodes from potentially a large number of candidates to form a virtual multi-antenna system, while at the same time designing their joint linear transmission strategies. We focus on two specific application scenarios: 1) multiple single antenna transmitters cooperatively transmit to a receiver; 2) a single transmitter transmits to a receiver with the help of a number of cooperative relays. We …


Joint Access Point Selection And Power Allocation For Uplink Wireless Networks, Mingyi Hong, Alfredo Garcia, Jorge Barrera, Stephen G. Wilson Jul 2013

Joint Access Point Selection And Power Allocation For Uplink Wireless Networks, Mingyi Hong, Alfredo Garcia, Jorge Barrera, Stephen G. Wilson

Mingyi Hong

We consider the distributed uplink resource allocation problem in a multi-carrier wireless network with multiple access points (APs). Each mobile user can optimize its own transmission rate by selecting a suitable AP and by controlling its transmit power. Our objective is to devise suitable algorithms by which mobile users can jointly perform these tasks in a distributed manner. Our approach relies on a game theoretic formulation of the joint power control and AP selection problem. In the proposed game, each user is a player with an associated strategy containing a discrete variable (the AP selection decision) and a continuous vector …


Distributed Linear Precoder Optimization And Base Station Selection For An Uplink Heterogeneous Network, Mingyi Hong, Zhi-Quan Luo Jun 2013

Distributed Linear Precoder Optimization And Base Station Selection For An Uplink Heterogeneous Network, Mingyi Hong, Zhi-Quan Luo

Mingyi Hong

In a heterogeneous wireless cellular network, each user may be covered by multiple access points such as macro/pico/relay/femto base stations (BS). An effective approach to maximize the sum utility (e.g., system throughput) in such a network is to jointly optimize users' linear procoders as well as their BS associations. In this paper, we first show that this joint optimization problem is NP-hard and thus is difficult to solve to global optimality. To find a locally optimal solution, we formulate the problem as a noncooperative game in which the users and the BSs both act as players. We introduce a set …


Extremes Of Nonlinear Vibration: Comparing Models Based On Moments, L-Moments, And Maximum Entropy, Steven R. Winterstein, Cameron A. Mackenzie May 2013

Extremes Of Nonlinear Vibration: Comparing Models Based On Moments, L-Moments, And Maximum Entropy, Steven R. Winterstein, Cameron A. Mackenzie

Cameron A. MacKenzie

Wind and wave loads on offshore structures show nonlinear effects, which require nonGaussian statistical models. Here we critically review the behavior of various nonGaussian models. We first survey moment-based models; in particular, the four-moment “Hermite” model, a cubic transformation often used in wind and wave applications. We then derive an “L-Hermite” model, an alternative cubic transformation calibrated by the response “L-moments” rather than its ordinary statistical moments. These L-moments have recently found increasing use, in part because they show less sensitivity to distribution tails than ordinary moments. We find here, however, that these L-moments may not convey sufficient information to …


Joint Base Station Clustering And Beamformer Design For Partial Coordinated Transmission In Heterogeneous Networks, Mingyi Hong, Ruoyu Sun, Hadi Baligh, Zhi-Quan Luo Feb 2013

Joint Base Station Clustering And Beamformer Design For Partial Coordinated Transmission In Heterogeneous Networks, Mingyi Hong, Ruoyu Sun, Hadi Baligh, Zhi-Quan Luo

Mingyi Hong

We consider the interference management problem in a multicell MIMO heterogeneous network. Within each cell there is a large number of distributed micro/pico base stations (BSs) that can be potentially coordinated for joint transmission. To reduce coordination overhead, we consider user-centric BS clustering so that each user is served by only a small number of (potentially overlapping) BSs. Thus, given the channel state information, our objective is to jointly design the BS clustering and the linear beamformers for all BSs in the network. In this paper, we formulate this problem from a {sparse optimization} perspective, and propose an efficient algorithm …


Empirical Data And Regression Analysis For Estimation Of Infrastructure Resilience With Application To Electric Power Outages, Cameron A. Mackenzie, Kash Barker Jan 2013

Empirical Data And Regression Analysis For Estimation Of Infrastructure Resilience With Application To Electric Power Outages, Cameron A. Mackenzie, Kash Barker

Cameron A. MacKenzie

Recent natural disasters have highlighted the need for increased planning for disruptive events. Forecasting damage and time that a system will be inoperable is important for disruption planning. The resilience of critical infrastructure systems, or their ability to recover quickly from a disruption, can mitigate adverse consequences of the disruption. This paper quantifies the resilience of a critical infrastructure sector through the dynamic inoperability input-output model (DIIM). The DIIM, which describes how inoperability propagates through a set of interdependent industry and infrastructure sectors following a disruptive event, includes a resilience parameter that has not yet been adequately assessed. This paper …


A Unified Convergence Analysis Of Block Successive Minimization Methods For Nonsmooth Optimization, Meisam Razaviyayn, Mingyi Hong, Zhi-Quan Luo Jan 2013

A Unified Convergence Analysis Of Block Successive Minimization Methods For Nonsmooth Optimization, Meisam Razaviyayn, Mingyi Hong, Zhi-Quan Luo

Mingyi Hong

The block coordinate descent (BCD) method is widely used for minimizing a continuous function f of several block variables. At each iteration of this method, a single block of variables is optimized, while the remaining variables are held fixed. To ensure the convergence of the BCD method, the subproblem of each block variable needs to be solved to its unique global optimal. Unfortunately, this requirement is often too restrictive for many practical scenarios. In this paper, we study an alternative inexact BCD approach which updates the variable blocks by successively minimizing a sequence of approximations of f which are either …


Linear Transceiver Design For A Mimo Interfering Broadcast Channel Achieving Max–Min Fairness, Meisam Razaviyayn, Mingyi Hong, Zhi-Quan Luo Jan 2013

Linear Transceiver Design For A Mimo Interfering Broadcast Channel Achieving Max–Min Fairness, Meisam Razaviyayn, Mingyi Hong, Zhi-Quan Luo

Mingyi Hong

This problem can be formulated as maximizing the minimum rate among all the users in an interfering broadcast channel (IBC). In this paper we show that when the number of antennas is at least two at each of the transmitters and the receivers, the min rate maximization problem is NP-hard in the number of users. Moreover, we develop a low-complexity algorithm for this problem by iteratively solving a sequence of convex subproblems. We theoretically establish the global convergence of the proposed algorithm to the set of stationary points, which may be suboptimal due to the non-convexity of the original minimum …