Smart Grid Technologies in Europe: An Overview

The old electricity network infrastructure has proven to be inadequate, with respect to modern challenges such as alternative energy sources, electricity demand and energy saving policies. Moreover, Information and Communication Technologies (ICT) seem to have reached an adequate level of reliability and flexibility in order to support a new concept of electricity network—the smart grid. In this work, we will analyse the state-of-the-art of smart grids, in their technical, management, security, and optimization aspects. We will also provide a brief overview of the regulatory aspects involved in the development of a smart grid, mainly from the viewpoint of the European Unio

BRAHMS: Novel middleware for integrated systems computation

Biological computational modellers are becoming increasingly interested in building large, eclectic models, including components on many different computational substrates, both biological and non-biological. At the same time, the rise of the philosophy of embodied modelling is generating a need to deploy biological models as controllers for robots in real-world environments. Finally, robotics engineers are beginning to find value in seconding biomimetic control strategies for use on practical robots. Together with the ubiquitous desire to make good on past software development effort, these trends are throwing up new challenges of intellectual and technological integration (for example across scales, across disciplines, and even across time) - challenges that are unmet by existing software frameworks. Here, we outline these challenges in detail, and go on to describe a newly developed software framework, BRAHMS. that meets them. BRAHMS is a tool for integrating computational process modules into a viable, computable system: its generality and flexibility facilitate integration across barriers, such as those described above, in a coherent and effective way. We go on to describe several cases where BRAHMS has been successfully deployed in practical situations. We also show excellent performance in comparison with a monolithic development approach. Additional benefits of developing in the framework include source code self-documentation, automatic coarse-grained parallelisation, cross-language integration, data logging, performance monitoring, and will include dynamic load-balancing and 'pause and continue' execution. BRAHMS is built on the nascent, and similarly general purpose, model markup language, SystemML. This will, in future, also facilitate repeatability and accountability (same answers ten years from now), transparent automatic software distribution, and interfacing with other SystemML tools. (C) 2009 Elsevier Ltd. All rights reserved

5G & SLAs: Automated proposition and management of agreements towards QoS enforcement

Efficient Service Level Agreements (SLA) management and anticipation of Service Level Objectives (SLO) breaches become mandatory to guarantee the required service quality in software- defined and 5G networks. To create an operational Network Service, it is highly envisaged to associate it with their network-related parameters that reflect the corresponding quality levels. These are included in policies but while SLAs target usually business users, there is a challenge for mechanisms that bridge this abstraction gap. In this paper, a generic black box approach is used to map high-level requirements expressed by users in SLAs to low-level network parameters included in policies, enabling Quality of Service (QoS) enforcement by triggering the required policies and manage the infrastructure accordingly. In addition, a mechanism for determining the importance of different QoS parameters is presented, mainly used for “relevant” QoS metrics recommendation in the SLA template

Using Wireless Communications To Enable Decentralized Analysis and Control of Smart Distribution Systems

The smart grid is a multidisciplinary approach that aims to revolutionize the whole electricity supply chain including generation, transmission and distribution systems in order to overcome the multiple challenges currently facing the electric power grid. The smart grid could be seen as a modern electrical power grid in which information as well as electricity flows among all nodes in the system, information is continuously collected, processed and hence used to control and coordinate the different system components such as distributed generation (DG) units, capacitor banks, voltage regulating transformers, etc. Therefore distributed intelligence and two-way data communication links are essential components in implementing the smart grid vision. There are numerous research efforts that focus on implementing the smart grid vision in electrical power distribution systems, most of which only target one aspect of the distribution system control and operation, e.g. a control system for voltage control, another one for DG control, a third one for protection, etc. The coexistence of such control strategies in a distribution system raises some concerns about their overall performance, their interactions with the other control strategies, and whether these control systems can adapt to changes in distribution system connectivity. In this PhD thesis we try to address these issues by proposing an implementation of the smart grid vision for distribution systems that provides an integrated design of power systems, communication systems and control strategies. A unified and flexible framework that incorporates all the different aspects of distribution system control and operation is proposed. Distributed processing units equipped with wireless communication capabilities are used to continuously process the local data along with the data received from other nodes and forward the results to neighboring nodes in the system, which in turn process the received data and share the results with their neighbors. Consequently, changes in any of the system components (load values, status of DG etc.) are taken into account in the calculations as soon as they occur, and the results are forwarded to relevant nodes in the systems. This way the information “propagates” throughout the system resulting in a seamless control and coordination among all the system components. Simulation of the electrical power distribution and the communication systems reveal the effectiveness of the proposed framework to control and coordinate multiple capacitor banks, DG units and voltage regulating transformers with changing load levels. It also reveals the potential of the proposed framework to operate in real-time by combining the real-time measured quantities with computer analysis in order to control the different system components within the time frame of normal non-emergency operating conditions. An experimental setup is built and used as a test bed for the proposed framework in order to assess the performance of the different ideas and techniques proposed in this thesis

Simulation modelling and visualisation: toolkits for building artificial worlds

Simulations users at all levels make heavy use of compute resources to drive computational simulations for greatly varying applications areas of research using different simulation paradigms. Simulations are implemented in many software forms, ranging from highly standardised and general models that run in proprietary software packages to ad hoc hand-crafted simulations codes for very specific applications. Visualisation of the workings or results of a simulation is another highly valuable capability for simulation developers and practitioners. There are many different software libraries and methods available for creating a visualisation layer for simulations, and it is often a difficult and time-consuming process to assemble a toolkit of these libraries and other resources that best suits a particular simulation model. We present here a break-down of the main simulation paradigms, and discuss differing toolkits and approaches that different researchers have taken to tackle coupled simulation and visualisation in each paradigm

Uso del modelo roms (Sistema de Modelado Oceánico Regional) para mejorar la predicción de la temperatura de la superficie del agua de mar del modelo mercator

Global models are generally capable of reproducing the observed trends in the globally averaged sea surface temperature (SST). However, the global models do not perform as well on regional scales. Here, we present an ocean forecast system based on the Regional Ocean Modelling System (ROMS), the boundary conditions come from the MERCATOR ocean system for the North Atlantic (1/6° horizontal resolution). The system covers the region of the northwestern Iberian Peninsula with a horizontal resolution of 1/36°, forced with the Weather Research and Forecasting Model (WRF) and the Soil Water Assessment Tool (SWAT). The ocean model results from the regional ocean model are validated using real-time SST and observations from the MeteoGalicia, INTECMAR and Puertos Del Estado real-time observational networks. The validation results reveal that over a one-year period the mean absolute error of the SST is less than 1°C, and several sources of measured data reveal that the errors decrease near the coast. This improvement is related to the inclusion of local forcing not present in the boundary condition model.Los modelos globales son capaces de reproducir con suficiente fiabilidad las tendencias observadas a gran escala en la SST (temperatura la superficie del agua del mar, por sus siglas en inglés). Sin embargo estos modelos no muestran tanta precisión en escalas locales. En este trabajo se presenta un sistema de predicción oceánico basado en el modelo regional oceánico ROMS anidado al modelo oceánico MERCATOR (resolución 1/6°) para el Atlántico Norte. El sistema se extiende a lo largo del noroeste de la Península Ibérica con una resolución horizontal de 1/36° y forzado con los modelos WRF para las condiciones atmosféricas y el modelo SWAT para los caudales de los ríos. El sistema de predicción se validó utilizando SST de OSTIA y observaciones provenientes de la redes de medición en tiempo real de Puertos del Estado, Intecmar y Meteogalicia. Los resultados muestran que para el periodo de un año estudiado el error medio absoluto de la SST es menor de 1°C, y las comparaciones contra observaciones puntuales muestran que este error es incluso menor cerca de costa. Los autores estiman que este comportamiento se debe a la inclusión de diferentes forzamientos locales no presentes en el modelo de condiciones de contorno

Semantic array programming in data-poor environments: assessing the interactions of shallow landslides and soil erosion

This research was conducted with the main objective to better integrate and quantify the role of water-induced shallow landslides within soil erosion processes, with a particular focus on data-poor conditions. To fulfil the objectives, catchment-scale studies on soil erosion by water and shallow landslides were conducted. A semi-quantitative method that combines heuristic, deterministic and probabilistic approaches is here proposed for a robust catchment-scale assessment of landslide susceptibility when available data are scarce. A set of different susceptibility-zonation maps was aggregated exploiting a modelling ensemble. Each susceptibility zonation has been obtained by applying heterogeneous statistical techniques such as logistic regression (LR), relative distance similarity (RDS), artificial neural network (ANN), and two different landslide-susceptibility techniques based on the infinite slope stability model. The good performance of the ensemble model, when compared with the single techniques, make this method suitable to be applied in data-poor areas where the lack of proper calibration and validation data can affect the application of physically based or conceptual models. A new modelling architecture to support the integrated assessment of soil erosion, by incorporating rainfall induced shallow landslides processes in data-poor conditions, was developed and tested in the study area. This proposed methodology is based on the geospatial semantic array programming paradigm. The integrated data-transformation model relies on a modular architecture, where the information flow among modules is constrained by semantic checks. By analysing modelling results within the study catchment, each year, on average, mass movements are responsible for a mean increase in the total soil erosion rate between 22 and 26% over the pre-failure estimate. The post-failure soil erosion rate in areas where landslides occurred is, on average, around 3.5 times the pre-failure value. These results confirm the importance to integrate landslide contribution into soil erosion modelling. Because the estimation of the changes in soil erosion from landslide activity is largely dependent on the quality of available datasets, this methodology broadens the possibility of a quantitative assessment of these effects in data-poor regions

Efficient integration of software components for scientific simulations

Abstract unavailable please refer to PD

Integration of noise modelling into RF receiver design

A thesis submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, 2017The scientific requirements for Radio Frequency (RF) receivers especially for Radio Astronomy have become more demanding, requiring: compact, low-profile, multi and wideband antennas and more sensitive receivers. Integration of the antenna into the receiver system is often critical to meet these demands. Noise theory to model these more complex systems is well developed but is not implemented in commercial solvers, given the niche market of the receivers it is only available using specialised software. If the system is closely coupled, it becomes necessary for design to incorporate Electromagnetic (EM) and Microwave (MW) modelling into the multi port noise modelling. CAESAR, a combined noise and EM/MW modelling code is available, but to use it requires the exclusive use of the CAESAR software, which is impractical given the utility and wide use of commercial solvers. Mathematical methods are developed to incorporate commercial solvers into the more specialised CAESAR, validated using a folded dipole and applied to a wideband Eleven antenna system, a compact form of a log periodic dipole array. The Eleven antenna consist of eight single ended or four differential ports, with a closely coupled feeding arrangement. Cryogenic measurements are done to verify the modelling, the measured sensitivity matches with the model closely in amplitude and shape, giving confidence to the approach, and allowing modelling but not system optimisation. Optimising the antenna based on receiver design and still being able to use commercial code requires the external scripting of a commercial solver. The EDITFEKO (card based) module of FEKO (a powerful and versatile solver) is used along with the meshing software GMSH and GNU Octave. Optimisation of system sensitivity is demonstrated on a choke horn fed reflector system at 1420MHz. This optimisation method is applied to a practical application, an octave band system (4:5 GHz to 9 GHz) for the Hartebeesthoek Radio Observatory. The design is split into smaller simulations using waveguide modes and the associated S–parameters, the techniques are presented and checked on a truncated system. Initial design and optimisation are given. The combining of specialised multiport noise modelling design and optimisation within commercial EM/MW solvers allows more sensitive and specialised receivers to be built. Index terms— noise modelling, wideband, multiport, corrugated horn, octave band receiver, EM/MW optimisationMT201