101 research outputs found

    The DREAM innovative software architecture for high DG-RES distribution grids

    Get PDF
    The DREAM software architecture model describes a reference class model, that aids in integrating the different components for active distribution grids. Theapplication domains, in which the framework can be used range from simulation (proof-of-concept) to implementation (proof-of feasibility). The frameworkfacilitates interoperability on the software and hardware level as well as from the communication technology level. The framework was designed from a use casesperspective. The major functionality implemented relates to flexible, heterarchic aggregation and coordination ofdevices involved in demand and supply of electricity. In the grid context aim, is to achieve a common objective, prioritize actions and operate on various timescales of grid operational and market functions. To that end, in the framework, monitoring data are handled and stored in a distributed fashion in order to directly steer or coordinate the operation of devices. These persistent dataalso allow handling forecasts and create interaction possibilities with actors or communities of actors on global and local markets and with operations in activedistribution grids and customer energy management. A first implementation is now being built

    Agilometer: An Effective Implementation of Internet of Things for Agile Demand Response

    Get PDF
    Transactive based control mechanism (TCM) needs the IoT environment to fully explore flexibility potential from the end-users to offer to involved actors of the smart energy system. On the other hand, many IoT based energy management systems are already available to a market. This paper presents an ap-proach to connect the current demand-driven (top-down) energy management system (EMS) with a market-driven (bottom-up) demand response program. To this end, this paper considers multi-agent system (MAS) to realize the approach and introduces the concept and standardize design of Agilometer. It is described as an elemental agent of the approach. Proposed by authors Agilometer consists of three different functional blocks, which are formulated as an IoT platform according to the LonWorks standard. Moreover, the paper also performs an evaluation study in order to validate the proposed concept and design

    The Detection of a Massive Chain of Dark H i Clouds in the GAMA G23 Field

    Get PDF
    We report on the detection of a large, extended H i cloud complex in the Galaxy and Mass Survey G23 field, located at a redshift of z ∼0.03, observed as part of the MeerKAT Habitat of Galaxies Survey campaign (a pilot survey to explore the mosaicing capabilities of the MeerKAT telescope). The cloud complex, with a total mass of 1010.0 M, lies in proximity to a large galaxy group with M dyn ∼1013.5 M. We identify seven H peak concentrations, interconnected as a tenuous chain structure, extending ∼400 kpc from east to west, with the largest (central) concentration containing 109.7 M in H gas distributed across 50 kpc. The main source is not detected in ultraviolet, optical, or infrared imaging. The implied gas mass-to-light ratio (M H I/L r) is extreme (>1000) even in comparison to other dark clouds. The complex has very little kinematic structure (110 km s-1), making it difficult to identify cloud rotation. Assuming pressure support, the total mass of the central concentration is > 1010.2 M, while a lower limit to the dynamical mass in the case of full rotational support is 1010.4 M. If the central concentration is a stable structure, it has to contain some amount of unseen matter, but potentially less than is observed for a typical galaxy. It is, however, not clear whether the structure has any gravitationally stable concentrations. We report a faint UV-optical-infrared source in proximity to one of the smaller concentrations in the gas complex, leading to a possible stellar association. The system nature and origins is enigmatic, potentially being the result of an interaction with or within the galaxy group it appears to be associated with

    MeerKAT-16 HI observation of the dIrr galaxy WLM

    Get PDF
    We present observations and models of the kinematics and the distribution of the neutral hydrogen (Hi) in the isolated dwarf irregular galaxy, Wolf-Lundmark-Melotte (WLM). We observed WLM with the Green Bank Telescope (GBT) and as part of the MeerKAT Early Science Programme, where 16 dishes were available. The Hi disc of WLM extends out to a major axis diameter of 300 (8.5 kpc), and a minor axis diameter of 200 (5.6 kpc) as measured by the GBT. We use the MeerKAT data to model WLM using the TiRiFiC software suite, allowing us to t di erent tilted-ring models and select the one that best matches the observation. Our nal best- tting model is a at disc with a vertical thickness, a constant inclination and dispersion, and a radially-varying surface brightness with harmonic distortions. To simulate bar- like motions, we include second-order harmonic distortions in velocity in the tangential and the vertical directions. We present a model with only circular motions included and a model with non-circular motions. The latter describes the data better. Overall, the models reproduce the global distribution and the kinematics of the gas, except for some faint emission at the 2 level. We model the mass distribution of WLM with a pseudo-isothermal (ISO) and a Navarro-Frenk-White (NFW) dark matter halo models. The NFW and the ISO models t the derived rotation curves within the formal errors, but with the ISO model giving better reduced chi-square values. The mass distribution in WLM is dominated by dark matter at all radii.The MeerKAT telescope is operated by the South African Radio Astronomy Observatory, which is a facility of the Na- tional Research Foundation, an agency of the Department of Science and Innovation. This work is based upon research supported by the South African Research Chairs Initiative of the Department of Sci- ence and Technology and National Research Foundation. The nancial assistance of the South African Radio Astron- omy Observatory (SARAO) towards this research is hereby acknowledged (www.sarao.ac.za). PK is partially supported by the BMBF project 05A17PC2 for D-MeerKAT. AS acknowledges the Russian Science Foundation grant 19-12-00281 and the Program of development of M.V.http://mnras.oxfordjournals.orgam2021Physic

    GASP XXVI. HI gas in jellyfish galaxies : the case of JO201 and JO206

    Get PDF
    Please read abstract in the article.European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme grant agreement no. 679627 and no.833824, project name FORNAX and GASP, respectively. We acknowledge funding from the agreement ASI-INAF n.2017-14-H.0, as well as from the INAF main-stream funding programme. M. R’s research is supported by the SARAO HCD programme via the "New Scientific Frontiers with Precision Radio Interferometry" research group grant. M. R. acknowledges support from the Italian Ministry of Foreign A airs and International Cooperation (MAECI Grant Number ZA18GR02) and the South African Department of Science and Technology’s National Research Foundation (DST-NRF Grant Number 113121) as part of the ISARP RADIOSKY2020 Joint Research Scheme. B. V. and M. G. also acknowledge the Italian PRIN-Miur 2017 (PI A. Cimatti). Y. J. acknowledges financial support from CONICYT PAI (Concurso Nacional de Insercion en la Academia 2017), No. 79170132 and FONDECYT Iniciación 2018 No. 11180558. M. V. acknowledges support by the Netherlands Foundation for Scientific Research (NWO) through VICI grant 016.130.338.http://www.aanda.orgam2020Physic

    The extended H i halo of NGC 4945 as seen by MeerKAT

    Get PDF
    The State Agency for Research of the Spanish Ministry of Science, Innovation and Universities through the ‘Center of Excellence Severo Ochoa’ awarded to the Instituto de Astrofísica de Andalucía; the Economic Transformation, Industry, Knowledge and Universities Council of the Regional Government of Andalusia and the European Regional Development Fund from the European Union; the South African Radio Astronomy Observatory (SARAO); BMBF Verbundforschung; DFG Sonderforschungsbereich and the European Research Council (ERC).http://mnras.oxfordjournals.orghj2022Physic

    Anomalous gas in ESO 149-G003 : a MeerKAT-16 view

    Get PDF
    ESO 149-G003 is a close-by, isolated dwarf irregular galaxy. Previous observations with the ATCA indicated the presence of anomalous neutral hydrogen (⁠HI⁠) deviating from the kinematics of a regularly rotating disc. We conducted follow-up observations with the MeerKAT radio telescope during the 16-dish Early Science programme as well as with the MeerLICHT optical telescope. Our more sensitive radio observations confirm the presence of anomalous gas in ESO 149-G003, and further confirm the formerly tentative detection of an extraplanar HI component in the galaxy. Employing a simple tilted-ring model, in which the kinematics is determined with only four parameters but including morphological asymmetries, we reproduce the galaxy’s morphology, which shows a high degree of asymmetry. By comparing our model with the observed HI⁠, we find that in our model, we cannot account for a significant (but not dominant) fraction of the gas. From the differences between our model and the observed data cube, we estimate that at least 7–8 per cent of the HI in the galaxy exhibits anomalous kinematics, while we estimate a minimum mass fraction of less than 1 per cent for the morphologically confirmed extraplanar component. We investigate a number of global scaling relations and find that, besides being gas-dominated with a neutral gas-to-stellar mass ratio of 1.7, the galaxy does not show any obvious global peculiarities. Given its isolation, as confirmed by optical observations, we conclude that the galaxy is likely currently acquiring neutral gas. It is either re-accreting gas expelled from the galaxy or accreting pristine intergalactic material.http://mnras.oxfordjournals.orghj2022Physic

    SMART : de ontwerplogica

    No full text
    Het vakgebied van de regeltechniek is zeer geschikt om ontwikkelingen vanuit de computertechnologie toe te passen. Zo zijn er systemen met regelalgoritmes gebaseerd op technieken zoals neurale netwerken, fuzzy logic, genetische algoritmes en kennissystemen gebouwd. Binnen het onderzoeksproject SMART (Smart Multi Agent inteRnet Technology) is er samengewerkt om de mogelijkheden van nieuwe regelstrategieën middels agent technologie, intelligente actieve software [1], te onderzoeken. Agent technologie is een ontwikkeling afkomstig uit het vakgebied van de kunstmatige intelligentie, ook wel artificiële intelligentie (AI) genoemd. AI onderzoekt het fenomeen intelligentie en tracht intelligente systemen te ontwikkelen. Intelligent wordt hierbij opgevat als dat de systemen doelmatig en adaptief gedrag vertonen, onder wisselende omstandigheden. In theorie zijn agents software programma’s die veel overeenkomsten vertonen met bepaalde menselijke vaardigheden. Zo kunnen agents onthouden, leren, redeneren, plannen en communiceren. Ze kunnen in iets geloven, of wensen, intenties, doelen en plannen hebben. Maar in de huidige praktijk bezitten ze al deze eigenschappen. Een multi-agent systeem bestaat uit autonoom opererende programma’s (agents), waarbij iedere agent zijn eigen taak heeft in het systeem. De agenten kunnen met elkaar communiceren. Het uiteindelijke doel is om de agents gezamenlijk een complexe taak gezamenlijk door agents te laten uitvoeren. Hierbij onderhandelen de agents onderling om tot de optimale oplossing in de actuele situatie te komen

    An assessment of the influence of demand response on demand elasticity in electricity retail market

    No full text
    A transition towards a sustainable society is currently ongoing. In the electrical power system, this is reflected by the increasing share of renewable energy sources (RES). The weather dependence of some RES results in intermittent and volatile behaviour, thus matching supply and demand has become a challenge. Demand response (DR) is an emerging field which enables society to coop with upcoming challenges. One of the explored concepts to perform the DR is the price elasticity of demand. This paper presents a model to compute price elasticity matrices for typical households consisting of dispatchable appliances and a base load. Simulations of the model will demonstrate the price elastic response for different scenarios
    corecore