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Given a set I of symbols, a set J of positions of an array, a gain value ρij for allocating i∈I to j∈J, the connected assignment problem in arrays (CAPA) is the problem consisting in finding an assignment of one symbol i to each position j so as to maximize the sum of the gains under the constraint such that repeated symbols are adjacent in the array. CAPA has a direct application in radio resource allocation (RRA) in the uplink of the modern fourth‐generation (4G) wireless communication networks. We show that CAPA is NP‐hard. We present two integer linear programming formulations for CAPA and propose four heuristic solutions. They are compared using Monte Carlo simulations to generate instances compatible with a 4G system scenario as well as random instances based on a uniform distribution of the gains. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of cooperative networks based on non-orthogonal multiple access (NOMA) with multiple full-duplex decode-and-forward relays. Taking into account rate fairness between the users and assuming imperfect successive interference cancellation (SIC), the problem is formulated so that power allocation is performed adaptively by the multiple relays in order to maximize the minimum users’ achievable rate. We demonstrate that the proposed optimization problem is convex and a closed-form expression for the power allocation factor is derived. The attained results show that the proposed scheme achieves satisfactory results in terms of achievable rate, fairness, and outage probability when compared to other adaptive power allocation strategies. [ABSTRACT FROM AUTHOR]

Background: The Trypanosoma cruzi genome was sequenced from a hybrid strain (CL Brener). However, high allelic variation and the repetitive nature of the genome have prevented the complete linear sequence of chromosomes being determined. Determining the full complement of chromosomes and establishing syntenic groups will be important in defining the structure of T. cruzi chromosomes. A large amount of information is now available for T. cruzi and Trypanosoma brucei, providing the opportunity to compare and describe the overall patterns of chromosomal evolution in these parasites. Methodology/Principal Findings: The genome sizes, repetitive DNA contents, and the numbers and sizes of chromosomes of nine strains of T. cruzi from four lineages (TcI, TcII, TcV and TcVI) were determined. The genome of the TcI group was statistically smaller than other lineages, with the exception of the TcI isolate Tc1161 (José-IMT). Satellite DNA content was correlated with genome size for all isolates, but this was not accompanied by simultaneous amplification of retrotransposons. Regardless of chromosomal polymorphism, large syntenic groups are conserved among T. cruzi lineages. Duplicated chromosome-sized regions were identified and could be retained as paralogous loci, increasing the dosage of several genes. By comparing T. cruzi and T. brucei chromosomes, homologous chromosomal regions in T. brucei were identified. Chromosomes Tb9 and Tb11 of T. brucei share regions of syntenic homology with three and six T. cruzi chromosomal bands, respectively. Conclusions: Despite genome size variation and karyotype polymorphism, T. cruzi lineages exhibit conservation of chromosome structure. Several syntenic groups are conserved among all isolates analyzed in this study. The syntenic regions are larger than expected if rearrangements occur randomly, suggesting that they are conserved owing to positive selection. Mapping of the syntenic regions on T. cruzi chromosomal bands provides evidence for the occurrence of fusion and split events involving T. brucei and T. cruzi chromosomes. [ABSTRACT FROM AUTHOR]

Presents information on the results of numerical experiments with an optimal power flow (OPF) algorithm based on a parametric technique. Formulation of the parametric optimal power flow (POPF) as a non-linear programming problem; Strategies to follow optimal solution of POPF; Kinds of problem cases studied.

Despite the advent of fifth‐generation mobile networks in the next years, the Long‐Term Evolution system still have an important role in the mobile communication scenario. Moreover, the development of solutions that fulfill the demand of new multimedia applications as well as provide an efficient use of the energy resources is one of the drivers of future networks. Therefore, in this article, we deal with the total energy efficiency maximization problem subject to minimum satisfaction constraints per service and quality of service in the uplink of Long‐Term Evolution using single‐carrier frequency‐division multiple access. Although the formulated problem is a nonlinear combinatorial optimization problem, we obtain the optimal solution through algebraic manipulations and by using an iterative method. Motivated by the high computational complexity to obtain the optimal solution, we propose a heuristic solution with lower computational complexity. Realistic system‐level simulations indicate that the proposed solution presents good performance regarding both outage rate and energy efficiency. [ABSTRACT FROM AUTHOR]