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Full duplex (FD) in cloud radio access networks (C-RAN) has improved the overall system throughput at most to double the half duplex (HD) counterpart. Although there is an overall improvement in the throughput, it is mainly due to the downlink (DL) rate, while the uplink (UL) rate is highly degraded due to the substantial DL interference. In this paper, we showed how by employing a downlink power control (DLPC), the overall capacity could be improved along with UL rate improvement. In DL, we could achieve 2.9 times the HD rate and 1.5 times that of FD without DLPC. In UL, 1.6 times the HD rate and the improvement up to 3.49 bps/Hz from rates of the order 1 0 − 4 bps/Hz of FD without DLPC. We have also shown how by appropriately selecting DL and UL power control parameters, we can reduce the cluster size requirement in the FD C-RAN system and the fronthaul capacity requirements. We use Matern Cluster Process (MCP) to model the network. We provide coverage and rate as integral expressions in terms of special functions and algebraic terms. We also derive closed-form approximations for asymptotic rates and reflect few insights into the system design. [ABSTRACT FROM AUTHOR]

The current study is aimed at getting a further insight into the changes the fouling brings to the Vortex Induced Vibration (VIV) of circular cylinders. Instead of regular patterns considered in previous studies, using the Poisson Cluster Process, an aggregated spatial distribution was considered for the artificial marine fouling. This is believed to better simulate the natural settlement of the marine biofouling. Different coverage ratios and fouling shapes plus regular and aggregated distributions were considered. The towing tank VIV tests were conducted on elastically mounted rigid cylinders. The Reynolds number ranged from around 7.8 × 10 3 to 4.9 × 10 4 . On the whole, the maximum oscillation amplitude and the maximum lift force coefficient were meaningfully smaller in cylinders with either aggregated or regular fouling, as compared to those from the corresponding clean cylinder. Both aggregated and regular fouling were, thus, acting as VIV suppression devices. The suppression effectiveness increased by reduction in the coverage ratio of the artificial fouling. The effectiveness, however, reduced by the aggregation as compared to that with regular distribution. In general, the maximum VIV oscillations and the force coefficients appeared to be sensitive, in descending order, to coverage ratio, aggregation, flow incidence and the fouling shape. [ABSTRACT FROM AUTHOR]

Abstract: The distribution of the excess process describing heights of extreme values can be approximated by the distribution of a Poisson cluster process. An estimate of the accuracy of such an approximation has been derived in in terms of the Wasserstein distance. The paper presents a sharper estimate established in terms of the stronger total variation distance. We derive also a new bound to the accuracy of negative Binomial approximation to the distribution of the number of exceedances. [Copyright &y& Elsevier]