316,767 research outputs found

    Partitioning Method of Virtual Microgrid Based on Electrical Coupling Strength

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    © 2019 Automation of Electric Power Systems Press. With the fast development in the research of smart grid and Energy Internet, more and more distributed renewable energy and energy storage devices are connected into distribution networks, intelligent development of distribution network has become an inevitable trend. It is a big challenge for large-scale conventional distribution networks to be consistent with the requirements of free, equal and flexible interaction. Virtual microgrids with high internal convergence are proposed based on electrical coupling strength, which is partitioned from conventional power distribution networks. Furthermore, an implementation framework of virtual microgrids based on extended cyber, physical and socioeconomic is put forward, three-stage research problems of boundary division, resource optimization deployment and collaborative capability management are introduced. According to the first problem, by defining the electrical coupling strength, the classical Newman fast partitioning algorithm is upgraded in complicated network to realize the automatic optimization of boundary in virtual microgrids. Through case studies, the proposed algorithm is verified to be reasonable and efficient

    Partitioning Method of Virtual Microgrid Based on Electrical Coupling Strength

    Get PDF
    © 2019 Automation of Electric Power Systems Press. With the fast development in the research of smart grid and Energy Internet, more and more distributed renewable energy and energy storage devices are connected into distribution networks, intelligent development of distribution network has become an inevitable trend. It is a big challenge for large-scale conventional distribution networks to be consistent with the requirements of free, equal and flexible interaction. Virtual microgrids with high internal convergence are proposed based on electrical coupling strength, which is partitioned from conventional power distribution networks. Furthermore, an implementation framework of virtual microgrids based on extended cyber, physical and socioeconomic is put forward, three-stage research problems of boundary division, resource optimization deployment and collaborative capability management are introduced. According to the first problem, by defining the electrical coupling strength, the classical Newman fast partitioning algorithm is upgraded in complicated network to realize the automatic optimization of boundary in virtual microgrids. Through case studies, the proposed algorithm is verified to be reasonable and efficient

    The Resource Leveling Problem with multiple resources using an adaptive genetic algorithm

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    Resource management ensures that a project is completed on time and at cost, and that its quality is as previously defined; nevertheless, resources are scarce and their use in the activities of the project leads to conflicts in the schedule. Resource Leveling Problems consider how to make the resource consumption as efficient as possible. This paper presents a new Adaptive Genetic Algorithm for the Resource Leveling Problem with multiple resources, and its novelty lies in using the Weibull distribution to establish an estimation of the global optimum as a termination condition. The extension of the project deadline with a penalty is allowed, avoiding the increase in the project criticality punishing the shift of activities. The algorithmis tested with the standard Project Scheduling Problem Library PSPLIB, and a complete analysis and benchmarking test instances are presented. The proposed algorithm is implemented using VBA for Excel 2010 in order to provide a flexible and powerful decision support system that enables practitioners to choose between different feasible solutions to a problem, and in addition it is easily adjustable to the constraints and particular needs of each project in realistic environments.This study was partially funded by the Spanish Ministry of Science and Innovation (research project BIA2011-23602).Ponz Tienda, JL.; Yepes Piqueras, V.; Pellicer Armiñana, E.; Moreno Flores, J. (2013). The Resource Leveling Problem with multiple resources using an adaptive genetic algorithm. Automation in Construction. 29(1):161-172. doi:10.1016/j.autcon.2012.10.003S16117229

    A key management architecture and protocols for secure smart grid communications

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    Providing encrypted communications among power grid components is expected to be a basic requirement of smart grid systems in the future. Here, we propose a key management architecture and associated protocols tailored to support encrypted smart grid communications. The architecture consists of two levels structured around the grid control system hierarchy. At the top level, which consist of control centers and regional coordinators, a bottom-up key structure is adopted using hash chaining and a logical key hierarchy. The lower level of the architecture consists of the regional coordinators (i.e., substations and distribution systems) and remote ends (e.g., meters and pole-top sensors) and utilizes a top-down key management approach built on an inverse element method. The proposed key management schema supports the hierarchical structure of the smart grid control mechanisms, and it takes the resource and electronic/physical security differences of the control levels into account. We define a set of protocols utilizing the architecture to provide secure unicast, multicast, and broadcast communications. Furthermore, we illustrate how the architecture is flexible enough to easily handle power grid nodes joining and leaving the system at the different levels. Lastly, we compare the proposed schema with existing ones and show that our architecture can achieve efficient key management to provide secure communications. Copyright © 2016 John Wiley & Sons, Ltd

    Innovations through 5G-Crosshaul applications

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    Proceeding of: 2016 European Conference on Networks and Communications (EuCNC) 27-30 junio 2016 Athens, GreeceA transport network for 5G envisions integrating the fronthaul and backhaul segments (namely 5G-Crosshaul) into a single transport network. This requires a fully integrated and unified management of fronthaul and backhaul resources in a sharable, scalable and flexible way. The integrated and unified management of the transport network resources follows the Software Defined Networking (SDN) principles of centralization, decoupling between control and data plane and application ecosystem. Innovation to enable context-aware resource management and to provide system-wide optimization of QoS, as well as energy related objectives, lies on defining key applications as logical decision entities to program the underlying network and packet forwarding behaviour. This paper presents a set of 5G-Crosshaul SDN applications with the scope of (i) managing the 5G-Crosshaul resources, including not only network but also computing and storage resources, and (ii) offering efficient media distribution and traffic offloading solutions. In order to develop these applications in a real system, we identify the interactions between the applications and the control plane. Based on these interactions, we propose a two-layer application plane and specify the requirements of the applications on the Northbound Interface (NBI) of the control plane.This work has been supported by the H2020 project “5G-Crosshaul: The 5G Integrated fronthaul/backhaul” (671598)

    Cellular manufacturing against relocation: the most efficient way to transform plants

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    This paper presents a methodology to help decide whether a process-oriented plant would become more competitive by relocating its facilities in a low-cost country or by transforming it into an efficient plant by means of the implementation of a cellular layout with production driven by demand, managed in accordance with the principles of lean manufacturing. In this paper, our methodology is applied to an existing processoriented production system A set of key magnitudes and cost data attributed to the production plant and the way it is managed are calculated. These key magnitudes, related to production cycles and inventories, are easily calculated by means of an Operation-Time diagram. Fourteen types of manufacturing and distribution costs are considered including those costs due to the relocation strategy, which are mostly related to logistics. The paper includes the necessary calculations to transform the original plant by implementing three U-shaped flexible cells and to quantify the number of employees that are necessary, taking into account global takt time and cycle time of individual processes. Key production magnitudes and production and distribution costs are then calculated for the cellular implementation. Final conclusions show that an efficient implementation of cellular production processes pursuant to the lean management principles (low resource consumption, elimination of activities that do not contribute to value creation, maintenance, on-time deliveries, high quality…) is able to offset, at least in the studied case, the improvement in costs attributed to relocation strategies in process-oriented plants managed in a conventional style.Postprint (published version

    SDN/NFV-enabled satellite communications networks: opportunities, scenarios and challenges

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    In the context of next generation 5G networks, the satellite industry is clearly committed to revisit and revamp the role of satellite communications. As major drivers in the evolution of (terrestrial) fixed and mobile networks, Software Defined Networking (SDN) and Network Function Virtualisation (NFV) technologies are also being positioned as central technology enablers towards improved and more flexible integration of satellite and terrestrial segments, providing satellite network further service innovation and business agility by advanced network resources management techniques. Through the analysis of scenarios and use cases, this paper provides a description of the benefits that SDN/NFV technologies can bring into satellite communications towards 5G. Three scenarios are presented and analysed to delineate different potential improvement areas pursued through the introduction of SDN/NFV technologies in the satellite ground segment domain. Within each scenario, a number of use cases are developed to gain further insight into specific capabilities and to identify the technical challenges stemming from them.Peer ReviewedPostprint (author's final draft

    Management and Service-aware Networking Architectures (MANA) for Future Internet Position Paper: System Functions, Capabilities and Requirements

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    Future Internet (FI) research and development threads have recently been gaining momentum all over the world and as such the international race to create a new generation Internet is in full swing: GENI, Asia Future Internet, Future Internet Forum Korea, European Union Future Internet Assembly (FIA). This is a position paper identifying the research orientation with a time horizon of 10 years, together with the key challenges for the capabilities in the Management and Service-aware Networking Architectures (MANA) part of the Future Internet (FI) allowing for parallel and federated Internet(s)
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