82 research outputs found

    A P4 Data Plane for the Quantum Internet

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    The quantum technology revolution brings with it the promise of a quantum internet. A new -- quantum -- network stack will be needed to account for the fundamentally new properties of quantum entanglement. The first realisations of quantum networks are imminent and research interest in quantum network protocols has started growing. In the non-quantum world, programmable data planes have broken the pattern of ossification of the protocol stack and enabled a new -- software-defined -- network software architecture. Similarly, a programmable quantum data plane could pave the way for a software-defined quantum network architecture. In this paper, we demonstrate how we use P416_{16} to explore abstractions and device architectures for quantum networks

    Inter-domain Routing in Optical Networks with Wavelength Converters

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    With the increasing deployment of wavelengthdivision multiplexing (WDM) optical networks, the need for advanced lightpath provisioning algorithms and protocols in a multi-domain setting is becoming evident. In order to increase efficiency by relaxing the wavelength continuity constraint in WDM optical networks, wavelength converters are often placed at certain nodes in the network. In this paper, we study the efficiency of using converters in a multi-domain setting. We have made simple but important modifications to existing optical inter-domain routing protocols in order to utilize the power of wavelength converters and have tested their performance. These modifications can be seamlessly integrated into these protocols (i.e., without changing their algorithmic aspects) to significantly reduce their blocking ratio. We also show that there is a clear performance difference among the considered protocols.Peer ReviewedPostprint (author’s final draft

    Adaptive Resource Allocation for Virtualized Base Stations in O-RAN with Online Learning

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    Open Radio Access Network systems, with their virtualized base stations (vBSs), offer operators the benefits of increased flexibility, reduced costs, vendor diversity, and interoperability. Optimizing the allocation of resources in a vBS is challenging since it requires knowledge of the environment, (i.e., "external'' information), such as traffic demands and channel quality, which is difficult to acquire precisely over short intervals of a few seconds. To tackle this problem, we propose an online learning algorithm that balances the effective throughput and vBS energy consumption, even under unforeseeable and "challenging'' environments; for instance, non-stationary or adversarial traffic demands. We also develop a meta-learning scheme, which leverages the power of other algorithmic approaches, tailored for more "easy'' environments, and dynamically chooses the best performing one, thus enhancing the overall system's versatility and effectiveness. We prove the proposed solutions achieve sub-linear regret, providing zero average optimality gap even in challenging environments. The performance of the algorithms is evaluated with real-world data and various trace-driven evaluations, indicating savings of up to 64.5% in the power consumption of a vBS compared with state-of-the-art benchmarks

    Optimal siting and sizing of wind farms

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    AbstractIn this paper, we propose a novel technique to determine the optimal placement of wind farms, thereby taking into account wind characteristics and electrical grid constraints. We model the long-term variability of wind speed using a Weibull distribution according to wind direction intervals, and formulate the metrics that capture wind speed characteristics at a specific location, namely the arithmetic mean of wind speed, the theoretical wind power density and the capacity factor of a prospective wind power plant, to determine the feasibility of a wind power plant establishment. Furthermore, a linear optimization formulation is provided to determine the geographical locations and the installed capacities of wind farms, in order to maximize the expected annual wind power generation, while obeying the constraints from the electrical power grid and the transmission system operator. As a case study, the proposed wind speed model and the linear optimization formulation are used to evaluate the wind characteristics and the potential wind farm sites in Turkey

    Loss of MYO5B expression deregulates late endosome size which hinders mitotic spindle orientation

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    MYO5B; Epithelial architecture; Recycling endosomesMYO5B; Arquitectura epitelial; Reciclaje de endosomasMYO5B; Arquitectura epitelial; Reciclatge d'endosomesRecycling endosomes regulate plasma membrane recycling. Recently, recycling endosome–associated proteins have been implicated in the positioning and orientation of the mitotic spindle and cytokinesis. Loss of MYO5B, encoding the recycling endosome–associated myosin Vb, is associated with tumor development and tissue architecture defects in the gastrointestinal tract. Whether loss of MYO5B expression affects mitosis is not known. Here, we demonstrate that loss of MYO5B expression delayed cytokinesis, perturbed mitotic spindle orientation, led to the misorientation of the plane of cell division during the course of mitosis, and resulted in the delamination of epithelial cells. Remarkably, the effects on spindle orientation, but not cytokinesis, were a direct consequence of physical hindrance by giant late endosomes, which were formed in a chloride channel–sensitive manner concomitant with a redistribution of chloride channels from the cell periphery to late endosomes upon loss of MYO5B. Rab7 availability was identified as a limiting factor for the development of giant late endosomes. In accordance, increasing rab7 availability corrected mitotic spindle misorientation and cell delamination in cells lacking MYO5B expression. In conclusion, we identified a novel role for MYO5B in the regulation of late endosome size control and identify the inability to control late endosome size as an unexpected novel mechanism underlying defects in cell division orientation and epithelial architecture.AD: Association for International Cancer Research (AICR13-0245), https://www.aicr.org AD: European Regional Development Fund (ERDF; PI16/00540 and AC15/00066), https://ec.europa.eu/regional_policy/en/funding/erdf AD: Spanish Association Against Cancer (AECC GCA15152966ARAN), https://www.uicc.org AD: the Instituto de Salud Carlos III, https://www.isciii.es/Paginas/Inicio.aspx IZ: The Dutch Research Council, Domain Applied and Engineering Sciences, https://www.nwo.nl/en JK: The Netherlands Organisation for Health Research and Development, 91111.006, https://www.zonmw.nl/en/ JK: The Dutch Research Council, 175-010-2009-023, https://www.nwo.nl/en CK: Chinese Scholarship Council, https://www.chinesescholarshipcouncil.com/ QL: Chinese Scholarship Council, https://www.chinesescholarshipcouncil.com/ YC: Chinese Scholarship Council, https://www.chinesescholarshipcouncil.com
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