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Summary: In this paper, we consider the transmission over multiple access relay channel (MARC) in which the relay operates in half‐duplex mode. The main contribution of this paper is establishing the capacity of the multiple access half‐duplex relay channel (MAHRC). Toward achieving this goal, we first derive a new achievable rate region. While deriving the achievable rate region, well‐known encoding and decoding schemes, which are used for transmission and reception over the degraded broadcast channel and the multiple access channel, are used. In this transmission scheme, the transmission from the two sources via the half‐duplex relay, to the destination, is split into two phases. Afterwards, an outer bound to the transmission over the discrete memoryless MAHRC is developed. Consequently, we show that the achievable rate region matches the outer bound and therefore the capacity region is formed. Further, the capacity region is extended to the case of Gaussian channel. Additionally, many numerical examples are shown to validate our theoretical derivations. In particular, these numerical examples show that the achievable rate region, and then the capacity, that we derive is larger than the well‐known results in the literature. [ABSTRACT FROM AUTHOR]

The channel state information at the transmitter (CSIT) play an important role in the performance of wireless networks. The CSIT model can be delayed and imperfect‐quality, since the feedback link has a delay and the channel state information (CSI) feedback has distortion. In this paper, the degrees‐of‐freedom (DoF) region of the two‐user multiple‐input multiple‐output (MIMO) broadcast channel are characterised with delayed imperfect‐quality CSIT, where the antenna configurations can be arbitrary. The converse proof of DoF region is based on the enhancement of physically degraded channel. The achievability proof of DoF region is through a novel transmission scheme design, where the duration of each phase and the amount of transmitted symbols are configured based on the imperfect‐quality of delayed CSIT. As a result, it is shown that the DoF region with delayed imperfect‐quality CSIT is located between the DoF region with no CSIT and the DoF region with delayed CSIT. [ABSTRACT FROM AUTHOR]

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The autonomous public mass media must strengthen the linguistic and cultural diversity of a region. It is questioned whether its financing and management model is appropriate in view of the economic problems it often faces. It has been studied the efficiency of 11 Spanish public broadcasting channels using data envelopment analysis to know which ones have a higher efficiency and to determine in what ways should the lower efficiency channels improve. Furthermore, via bootstrapping, it is determined if variables such as having an indigenous language or the population affect the efficiency of the channel. [ABSTRACT FROM AUTHOR]

We investigate the nonlinear spillover and portfolio allocation characteristics of the US and Canadian energy equity portfolios. Our empirical study based on directional spillover index and non‐convex portfolio optimization show that the spillover effects in the aggregate are smaller for the US portfolio across time. However, when only the largest spillover transmitters and receivers are considered, the total spillover effects are lower for the Canadian portfolio relative to the US portfolio. These portfolio optimization results indicate lower portfolio allocation risk for the Canadian energy equities during the global financial crisis of 2008 and for the full sample period. [ABSTRACT FROM AUTHOR]

Connectivity between populations is important when considering conservation or the management of exploitation of vulnerable species. We investigated how populations of a broadcast‐spawning marine species (scallop, Pecten maximus) that occur in discrete geographic locations were connected to each other. Population genetic insights were related to the outputs from a three‐dimensional hydrodynamic model implemented with scallop larval behaviour to understand the extent to which these areas were linked by oceanographic processes and how this was altered by season and two contrasting years that had strongly different average temperature records (warm vs cold) to provide contrasting oceanographic conditions. Our results span from regional to shelf scale. Connectivity was high at a regional level (e.g. northern Irish Sea), but lower at scales >100 km between sites. Some localities were possibly isolated thus dependent on self‐recruitment to sustain local populations. Seasonal timing of spawning and inter‐annual fluctuations in seawater temperature influenced connectivity patterns, and hence will affect spatial recruitment. Summer rather than spring spawning increased connectivity among some populations, due to the seasonal strengthening of temperature‐driven currents. Furthermore, the warm year resulted in higher levels of modelled connectivity than the cold year. The combination of genetic and oceanographic approaches provided valuable insights into the structure and connectivity at a continental shelf scale. This insight provides a powerful basis for defining conservation management units and the appropriate scale for spatial management. Temporal fluctuations in temperature impact upon variability in connectivity, suggesting that future work should account for ocean warming when investigating population resilience. [ABSTRACT FROM AUTHOR]