Maximum Achievable Utility Research Articles

Stability and Dynamic Control of Underlay Mobile Edge Networks

This paper studies the stability and dynamic control of underlay mobile edge networks. First, the stability region for a multiuser edge network is obtained under the assumption of full channel state information. This result provides a benchmark figure for comparing performance of the proposed algorithms. Second, a centralized joint flow control and scheduling algorithm is proposed to stabilize the queues of edge devices while respecting the average and instantaneous interference power constraints at the core access point. This algorithm is proven to converge to a utility point arbitrarily close to the maximum achievable utility within the stability region. Finally, more practical implementation issues such as distributed scheduling are examined by designing efficient scheduling algorithms taking advantage of communications diversity. The proposed distributed solutions utilize mini slots for contention resolution and achieve a certain fraction of the utility optimal point. The performance lower bounds for distributed algorithms are determined analytically. The detailed simulation study is performed to pinpoint the cost of distributed control for mobile edge networks with respect to centralized control.

Health-Related Quality of Life in People Living with Psychotic Illness and Factors Associated with Its Variation

ObjectivesTo establish whether the four-dimensional Assessment of Quality of Life (AQoL-4D) produces robust utility values in adults with psychotic illness, and identify health inequalities compared with the general population. MethodsThe AQoL-4D was completed by 1613 individuals with an International Classification of Diseases, Tenth Revision, psychotic illness in the 2010 Australian National Survey of Psychosis. Utilities were assessed for this sample and 20 subgroups, and were compared with general population norms. Modified Cohen d was used as an index of effect size. Utilities were collapsed into 10 health-related quality-of-life (HRQOL) bands or decades. ResultsHRQOL in people with psychotic illness was half of the maximum achievable utility (half-“full health”) with a mean utility of 0.49 (95% confidence interval [CI] 0.48–0.51), and showing substantial variability across subgroups. Participants with essentially normal functioning had the highest mean utility (0.72; 95% CI 0.68–0.77), and those with very poor perceived mental health had the lowest (0.22; 95% CI 0.18–0.26). These subgroups showed the most variability. Negative symptoms also gave rise to substantial variation. Among diagnostic categories, only depressive psychosis had a large effect relative to delusional disorders. The distribution of utilities in people with psychotic illness differed markedly from that in the general population, with 6.8% versus 47.2% having values in the highest decade (>0.90–1.00). Utilities were lower in every age group in people with psychosis. ConclusionsProfound HRQOL impacts are revealed by the AQoL-4D in people with psychotic illness, and marked variations in utilities were observed for key subjective and objective measures. We provide a suite of utility values for economic modeling studies and recommend the AQoL-4D for assessing HRQOL in people with psychotic illness.

COOPERATIVE RESOURCE SHARING OVER SERVICE PROVIDERS POOL IN CLOUD RADIO ACCESS NETWORK

Existing confined wireless network needs a revolutionary change to support diversified data traffic expected in the near future. Cloud Radio Access Network (CRAN) is a new paradigm which will overcome the pitfalls of existing radio access network (RAN) architecture, since its foundation principle is to share resources over multiple service providers. The CRAN architecture needs optimized resource allocation algorithm to achieve the benefits of centralization. This work aims the optimization of resource allocation using CRAN bargaining scheduler (CRAN-BS) framework. In CRAN-BS, resource allocation is formulated as cooperative game between users of multiple service providers, solution of which is obtained using the Kalai-Smorodinsky bargaining solution (KSBS). The CRAN-KSBS approach benefits each user in proportion with user's maximum achievable utility obtained by considering a service provider (SP) acting alone in the network. The proposed CRAN-KSBS proves to improve spectral efficiency of network over non-cooperative traditional RAN for different traffic conditions. The fairness of solution over different service providers is further obtained by considering bargaining power based on instantaneous utility of SP.

Multi-Period Portfolio Rebalancing with Personal Tax

The practical advice to the multi-period portfolio rebalancing problem with personal tax is to make adjustments over a long period of time. The reason for this non-quantitative advice is that there is no dynamic or analytic solution to the problem due to its’ complexity. In this paper, we will quantify this advice within the context of maximizing a multi-period utility of consumption. We will show that while the monetary benefit of rebalancing is larger than the tax cost, in order to maximize this benefit, the current portfolio must be moved to the optimal portfolio prudently. We first investigate the benefit of a simple heuristic rebalancing rule, such as trading X percent of the current portfolio annually. Secondly, we will derive another simple rebalancing rule which is consistent with current continues time portfolio theory. It is based on the assumption that the unknown value function (the maximum achievable utility) can be approximated by a simple quadratic function. We show that this derived rebalancing rule is better than the first simple heuristic rebalancing rule.

Integrated Packet/Circuit Hybrid Network Field Trial With Production Traffic [Invited

We report the first field trials of an integrated packet/circuit hybrid optical network. In a long-haul field trial with production traffic, the mean capacity utilization of an Ethernet wavelength is doubled. The transport shares a single lightpath between the circuit and packet layers. Router bypassing is demonstrated at sub-wavelength granularity in a metro network field trial. In both trials the circuit quality of service is shown to be independent of the load of the network. The vacant resources in the circuit are utilized by the packet layer's statistical multiplexing in an interleaved manner without affecting the timing of the circuit. Inaddition, an analytical model that provides an upper bound on the maximum achievable utilization is presented.

Control of Wireless Networks With Secrecy

We consider the problem of cross-layer resource allocation in time-varying cellular wireless networks and incorporate information theoretic secrecy as a quality-of-service constraint. Specifically, each node in the network injects two types of traffic, private and open, at rates chosen in order to maximize a global utility function, subject to network stability and secrecy constraints. The secrecy constraint enforces an arbitrarily low mutual information leakage from the source to every node in the network, except for the sink node. We first obtain the achievable rate region for the problem for single- and multiuser systems assuming that the nodes have full channel state information (CSI) of their neighbors. Then, we provide a joint flow control, scheduling, and private encoding scheme, which does not rely on the knowledge of the prior distribution of the gain of any channel. We prove that our scheme achieves a utility arbitrarily close to the maximum achievable utility. Numerical experiments are performed to verify the analytical results and to show the efficacy of the dynamic control algorithm.

Bargaining Strategies for Networked Multimedia Resource Management

Multiuser multimedia applications such as enterprise streaming, surveillance, and gaming are recently emerging, and they are often deployed over bandwidth-constrained network infrastructures. To ensure the quality of service (QoS) required by the delay-sensitive and bandwidth intensive multimedia data for these applications, efficient resource (bandwidth) management becomes paramount. We propose to deploy the well-known game theoretic concept of bargaining to allocate the bandwidth fairly and optimally among multiple collaborative users. Specifically, we consider two bargaining solutions for our resource management problem: the Nash bargaining solution (NBS) and the Kalai-Smorodinsky bargaining solution (KSBS). We provide interpretations for the two investigated bargaining solutions for multiuser resource allocation: the NBS can be used to maximize the system utility, while the KSBS ensures that all users incur the same utility penalty relative to the maximum achievable utility. The bargaining strategies and solutions are implemented in the network using a resource manager, which explicitly considers the application-specific distortion for the bandwidth allocation. We show that the bargaining solutions exhibit important properties (axioms) that can be used for effective multimedia resource allocation. Moreover, we propose several criteria for determining bargaining powers for these solutions, which enable us to provide additional flexibility in choosing solution by taking into consideration the visual quality impact, the deployed spatiotemporal resolutions, etc. We also determine the complexity of these solutions for our application and quantify the performance of the proposed bargaining-based resource strategies for different scenarios.

A Distributed Scheduling Algorithm for Real-Time Communication on Slotted Shared Medium

Algorithms for arbitrating and scheduling transmissions from different transmitters sharing a common access medium arise often in the design of many shared and distributed systems. In this paper we present a distributed algorithm for arbitrating time-constrained transmissions on slotted shared access media. The two most important distinguishing features of our algorithm are: (1) unlike most of the other schemes that guarantee on-time transmission over shared media by centralized preallocation of slots, our algorithm is fully distributed and completely on-line; (2) it eliminates one of the common pitfalls of all slotted systems, that is, allocation in integral multiples of full slots. We derive sufficient conditions for schedulability and show that the proposed scheme achieves high levels of schedulable utilization. We also show that the schedulable utilization increases as the length of the allocation cycle increases and asymptotically approaches the maximum achievable utilization. We present a distributed slot access protocol to realize the proposed algorithm for ring architecture. The protocol can be easily modified for other topologies, such as bus and dual-bus networks. Using illustrative examples we demonstrate the effectiveness of the algorithm.