Advanced search in Research products
Research products
arrow_drop_down
Searching FieldsTerms
Any field
arrow_drop_down
includes
arrow_drop_down
Include:
The following results are related to Energy Research. Are you interested to view more results? Visit OpenAIRE - Explore.
9,705 Research products, page 1 of 971

  • Energy Research
  • Conference object
  • DE

10
arrow_drop_down
Relevance
arrow_drop_down
  • Publication . Conference object . Preprint . Article . Other literature type . 2021
    Open Access English
    Authors: 
    Sudhir Malik; S. Meehan; K. Lieret; Meirin Oan Evans; Michel Hernández Villanueva; Daniel S. Katz; G. A. Stewart; Peter Elmer; Sizar Aziz; Matthew Bellis; +37 more
    Countries: Germany, France
    Project: NSF | Collaborative Research: C... (1829729), NSF | S2I2: Institute for Resea... (1836650), NSF | Collaborative Research: C... (1829707)

    Long term sustainability of the high energy physics (HEP) research software ecosystem is essential for the field. With upgrades and new facilities coming online throughout the 2020s this will only become increasingly relevant throughout this decade. Meeting this sustainability challenge requires a workforce with a combination of HEP domain knowledge and advanced software skills. The required software skills fall into three broad groups. The first is fundamental and generic software engineering (e.g. Unix, version control,C++, continuous integration). The second is knowledge of domain specific HEP packages and practices (e.g., the ROOT data format and analysis framework). The third is more advanced knowledge involving more specialized techniques. These include parallel programming, machine learning and data science tools, and techniques to preserve software projects at all scales. This paper dis-cusses the collective software training program in HEP and its activities led by the HEP Software Foundation (HSF) and the Institute for Research and Innovation in Software in HEP (IRIS-HEP). The program equips participants with an array of software skills that serve as ingredients from which solutions to the computing challenges of HEP can be formed. Beyond serving the community by ensuring that members are able to pursue research goals, this program serves individuals by providing intellectual capital and transferable skills that are becoming increasingly important to careers in the realm of software and computing, whether inside or outside HEP Comment: For CHEP 2021 conference,sent for publication to CSBS Springer

  • Publication . Conference object . 2021
    Authors: 
    Thomas Prantl; Lukas Iffländer; Stefan Herrnleben; Simon Engel; Samuel Kounev; Christian Krupitzer;
    Publisher: ACM

    The interconnectivity of devices on the Internet of Things (IoT) provides many new and smart applications. However, the integration of many devices - especially by inexperienced users - might introduce several security threats. Further, several often used communication protocols in the IoT domain are not out-of-the-boxsecured. On the other hand, security inherently introduces overhead, resulting in a decrease in performance. The Message QueuingTelemetry Transport (MQTT) protocol is a popular communication protocol for IoT applications - for example, in Industry 4.0, railways, automotive, or smart homes. This paper analyzes the influence on performance when using MQTT with TLS in terms of throughput, connection build-up times, and energy efficiency using a reproducible testbed based on a standard off-the-shelf microcontroller. The results indicate that the impact of TLS on performance across all QoS levels depends on (i) the network situation and (ii) the connection reestablishment frequency. Thus, a negative influence of TLS on the performance is noticeable only in deteriorated networksituations or at a high connection reestablishment frequency.

  • Authors: 
    Richard Evarts Dilgren; Arthur R. Deemer; Kenneth B. Owens;
    Publisher: Society of Petroleum Engineers

    Steam foam formulations were developed to reduce steam mobility in the steam drive process. Several commercially available alkylbenzene sodium sulfonates and alpha olefin sodium sulfonates appear promising. Other foam components were nitrogen and sodium chloride. Ottawa sand packs were the primary screening tool used in the laboratory. Reduced steam foam mobility in the field was evidenced by significantly increased flowing bottom-hole pressures for the injectors. An increased rate of oil production was observed also.

  • Authors: 
    Mehdi Vali; Jan-Willem van Wingerden; Martin Kühn;
    Publisher: IEEE

    This paper studies the active rotor load controller design for a large wind turbine via individual pitch control (IPC). A multivariable IPC is designed to reject the periodic load disturbances, in an optimal manner, by penalizing the control effort according to the pitch actuator constraints. Frequency response analysis of the well-known multi-blade coordinate (MBC) transformation describes how the rotational speed variations influence the flexible modes of the blades. Therefore, a multivariable plant is constructed in the frequency-domain, compatible with applying the disturbance rejection control approaches. Then, a mixed sensitivity H∞ optimization problem is formulated based on the obtained MIMO model. The performance of the synthesized controller is analyzed and compared with the PI-based IPC. Finally, the dynamic load mitigation of the developed controller is studied through the fatigue load analysis with a high-fidelity aeroelastic simulator. Results show a significant amount of load alleviation in return for an even lower level of the pitch activity, with respect to the PI-based IPC.

  • Closed Access
    Authors: 
    Jorge Rodríguez; Iris Perner; Karsten Schmidt; Clemens Posten;

    Abstract A simple metabolic model for Saccharomyces cerevisiae was developed, considering anabolism and fermentative and respirative pathways. Several fed-batch experiments were carried out at different constant biomass growth rates and C/N ratios in the feed in order to investigate their effect on the protein content of the yeast cells. Model parameters were fitted to the experimental data and simulations were used to analyse the influence of the biomass growth rate and C:N ratio on the cell composition.

  • Open Access English
    Authors: 
    Mallick, Bishawjit;
    Country: Germany

    "In this article I investigated the complex relationship between disasters, migration and poverty in a case study carried out in one of the poorest and most disaster-prone countries in the world. The focus was set on individual household and community adaptation strategies. Through a literature review in this field I have developed and tested my own analytical model. In an extensive field survey, which was carried out in the southwest coastal region of Bangladesh, I asked around 280 residents who were affected by cyclone Aila in 2009. Original in this study is the explicit testing of the effectiveness of adaptive coping strategies to reduce the damage cost and its consequences to the social structural changes. Here, I considered ‘migration’ as a strategic step to cope with the adverse effect of cyclone Aila. In this study, I found that affected people act as hunters towards the relief materials immediately after the cyclone. When the relief programme was closed, male members of the family started moving towards nearer cities to find an income. Most of them started to pull rickshaws or to work as labourer in industries. They live at slum-environment to accumulate more money for their dependants; their out-migration from the family creates more social problems for their spouse as well. Accordingly, their spouse should take care of other family members and children. In most of the cases, those dependants move towards cities and and they also become migrants and start working there. However, it is evident that a lot of people do not bring their family and children and get married again. It introduces changes in local social structure. Furthermore, based on the income and asset distribution at the community level, this study developed societal cluster of migration and, correlating with previous disaster and census data, it introduces a new methodological tool for analysing disaster-migration nexus." [author's abstract]

  • Publication . Conference object . 2017
    Authors: 
    Tobias Schnelle; Adolf Schweer; Peter Schegner;
    Publisher: IEEE

    The increasing number of distributed energy resources, energy storage systems and controllable loads, summarized as decentralized actors (DAs), causes new challenges for grid operation and planning. At the same time, it leads to new capabilities of forming microgrids (MGs) with controllable generation, consumption and storage functionalities in public distribution systems. To utilize MGs for ensuring grid stability in critical situations, necessary communication technologies are cost intensive and have to meet high security and reliability requirements. Modular microgrids (MMGs), which are decoupled from the upstream grid by power electronic grid interconnectors, offer the chance to use grid frequency as cost efficient and reliable communication channel. This paper presents a novel approach to control MMGs by frequency variation. To demonstrate the potential of the concept, the MMG with its DAs is modeled in DIgSILENT PowerFactory and simulation results are depicted.

  • Open Access English
    Authors: 
    Giese, Lutz B.;
    Publisher: Technische Hochschule Wildau
    Country: Germany

    The greenhouse gases (GHG) carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) are considered mainly to be responsible for the additional anthropogenic greenhouse effect, the so-called “global warming”. In the private sector, the “Rational Use of Energy” can be a very effective tool (i) to reduce the greenhouse gas emissions, (ii) to decrease the annual energy costs and furthermore (iii) it prepares the integration of Renewable Energy Sources by saving conventional, mostly fossil energy. Aim of this paper is (i) to show that by applying energy saving measures, the primary energy demand and thus the individual (direct) carbon dioxide emission can be reduced in a relevant scale. (ii) It is to give laterally information about (ii.i) the energy market structure and (ii.ii) the legal backgrounds in the EU.

  • Authors: 
    Serguei Kondratenko; Leonard M. Rubin; Eric A. G. Webster;
    Publisher: IEEE

    This paper presents SIMS data for very high energy ion implantations of arsenic (1.9–8.0 MeV), boron (2.0–5.0 MeV), and phosphorus (4.0–8.0 MeV) from Axcelis’ PurionTM VXE implanter with comparison to TCAD simulation results. Arsenic is found to be highly sensitive to implant angle, requiring beam angle control better than 0.05°, and to be relatively insensitive to damage and is generally in good agreement with simulation. It is reported for the first time that the As profile for tilt/twist=1°/0° is more channeled than 0.5°/22°, indicating the significance of planar channeling for this condition even at tilt angles ≤1.0°. Boron is well described by the TCAD model except for a 2.0 MeV highly channeled implant where it underestimates the channeling. Phosphorus is found to be the most challenging to simulate with a general overestimation of the channeling tail.

  • Publication . Conference object . 2018
    Authors: 
    Laura Dente; Leila Guerriero; Nuno Carvalhais; Pedro Silva; Paula Soares; Paolo Ferrazzoli; Nazzareno Pierdicca;
    Publisher: SPIE

    A combined Position-Reflectometry Galileo receiver on board a low cost unmanned aerial platform (UAV) was developed in the framework of the Combined Positioning-Reflectometry Galileo Code Receiver for Forest Management project (COREGAL) with the main aims of evaluating the accurate positioning in areas where no GNSS ground infrastructures are available and of investigating the forest biomass mapping. In this context, the Soil and Vegetation Reflection Simulator (SAVERS) was employed to simulate GNSS-R data in order to analyze the GNSS-R sensitivity to biomass, to create a Look Up Table (LUT) of GNSS-R reflectivity and to carry out a biomass retrieval test. SAVERS simulated the mean power of the reflected GNSS-R signals by applying the integral bistatic equation taking into account the scattering contributions from soil and vegetation. It was shown that the GNSS-R sensitivity to forest biomass can be enhanced by filtering out the incoherent component of the signal, i.e. by using a long coherent integration time. A LUT was created by running SAVERS for a realistic range of the input parameters. Moreover, a GNSS-R synthetic dataset was generated for the case of a cork oak open forest in Portugal and a retrieval test was carried out. A neural network with two hidden layers was trained on the LUT and the forest biomass was estimated from the synthetic data. The biomass mean retrieval error was approximately 10 t/ha.

Advanced search in Research products
Research products
arrow_drop_down
Searching FieldsTerms
Any field
arrow_drop_down
includes
arrow_drop_down
Include:
The following results are related to Energy Research. Are you interested to view more results? Visit OpenAIRE - Explore.
9,705 Research products, page 1 of 971
  • Publication . Conference object . Preprint . Article . Other literature type . 2021
    Open Access English
    Authors: 
    Sudhir Malik; S. Meehan; K. Lieret; Meirin Oan Evans; Michel Hernández Villanueva; Daniel S. Katz; G. A. Stewart; Peter Elmer; Sizar Aziz; Matthew Bellis; +37 more
    Countries: Germany, France
    Project: NSF | Collaborative Research: C... (1829729), NSF | S2I2: Institute for Resea... (1836650), NSF | Collaborative Research: C... (1829707)

    Long term sustainability of the high energy physics (HEP) research software ecosystem is essential for the field. With upgrades and new facilities coming online throughout the 2020s this will only become increasingly relevant throughout this decade. Meeting this sustainability challenge requires a workforce with a combination of HEP domain knowledge and advanced software skills. The required software skills fall into three broad groups. The first is fundamental and generic software engineering (e.g. Unix, version control,C++, continuous integration). The second is knowledge of domain specific HEP packages and practices (e.g., the ROOT data format and analysis framework). The third is more advanced knowledge involving more specialized techniques. These include parallel programming, machine learning and data science tools, and techniques to preserve software projects at all scales. This paper dis-cusses the collective software training program in HEP and its activities led by the HEP Software Foundation (HSF) and the Institute for Research and Innovation in Software in HEP (IRIS-HEP). The program equips participants with an array of software skills that serve as ingredients from which solutions to the computing challenges of HEP can be formed. Beyond serving the community by ensuring that members are able to pursue research goals, this program serves individuals by providing intellectual capital and transferable skills that are becoming increasingly important to careers in the realm of software and computing, whether inside or outside HEP Comment: For CHEP 2021 conference,sent for publication to CSBS Springer

  • Publication . Conference object . 2021
    Authors: 
    Thomas Prantl; Lukas Iffländer; Stefan Herrnleben; Simon Engel; Samuel Kounev; Christian Krupitzer;
    Publisher: ACM

    The interconnectivity of devices on the Internet of Things (IoT) provides many new and smart applications. However, the integration of many devices - especially by inexperienced users - might introduce several security threats. Further, several often used communication protocols in the IoT domain are not out-of-the-boxsecured. On the other hand, security inherently introduces overhead, resulting in a decrease in performance. The Message QueuingTelemetry Transport (MQTT) protocol is a popular communication protocol for IoT applications - for example, in Industry 4.0, railways, automotive, or smart homes. This paper analyzes the influence on performance when using MQTT with TLS in terms of throughput, connection build-up times, and energy efficiency using a reproducible testbed based on a standard off-the-shelf microcontroller. The results indicate that the impact of TLS on performance across all QoS levels depends on (i) the network situation and (ii) the connection reestablishment frequency. Thus, a negative influence of TLS on the performance is noticeable only in deteriorated networksituations or at a high connection reestablishment frequency.

  • Authors: 
    Richard Evarts Dilgren; Arthur R. Deemer; Kenneth B. Owens;
    Publisher: Society of Petroleum Engineers

    Steam foam formulations were developed to reduce steam mobility in the steam drive process. Several commercially available alkylbenzene sodium sulfonates and alpha olefin sodium sulfonates appear promising. Other foam components were nitrogen and sodium chloride. Ottawa sand packs were the primary screening tool used in the laboratory. Reduced steam foam mobility in the field was evidenced by significantly increased flowing bottom-hole pressures for the injectors. An increased rate of oil production was observed also.

  • Authors: 
    Mehdi Vali; Jan-Willem van Wingerden; Martin Kühn;
    Publisher: IEEE

    This paper studies the active rotor load controller design for a large wind turbine via individual pitch control (IPC). A multivariable IPC is designed to reject the periodic load disturbances, in an optimal manner, by penalizing the control effort according to the pitch actuator constraints. Frequency response analysis of the well-known multi-blade coordinate (MBC) transformation describes how the rotational speed variations influence the flexible modes of the blades. Therefore, a multivariable plant is constructed in the frequency-domain, compatible with applying the disturbance rejection control approaches. Then, a mixed sensitivity H∞ optimization problem is formulated based on the obtained MIMO model. The performance of the synthesized controller is analyzed and compared with the PI-based IPC. Finally, the dynamic load mitigation of the developed controller is studied through the fatigue load analysis with a high-fidelity aeroelastic simulator. Results show a significant amount of load alleviation in return for an even lower level of the pitch activity, with respect to the PI-based IPC.

  • Closed Access
    Authors: 
    Jorge Rodríguez; Iris Perner; Karsten Schmidt; Clemens Posten;

    Abstract A simple metabolic model for Saccharomyces cerevisiae was developed, considering anabolism and fermentative and respirative pathways. Several fed-batch experiments were carried out at different constant biomass growth rates and C/N ratios in the feed in order to investigate their effect on the protein content of the yeast cells. Model parameters were fitted to the experimental data and simulations were used to analyse the influence of the biomass growth rate and C:N ratio on the cell composition.

  • Open Access English
    Authors: 
    Mallick, Bishawjit;
    Country: Germany

    "In this article I investigated the complex relationship between disasters, migration and poverty in a case study carried out in one of the poorest and most disaster-prone countries in the world. The focus was set on individual household and community adaptation strategies. Through a literature review in this field I have developed and tested my own analytical model. In an extensive field survey, which was carried out in the southwest coastal region of Bangladesh, I asked around 280 residents who were affected by cyclone Aila in 2009. Original in this study is the explicit testing of the effectiveness of adaptive coping strategies to reduce the damage cost and its consequences to the social structural changes. Here, I considered ‘migration’ as a strategic step to cope with the adverse effect of cyclone Aila. In this study, I found that affected people act as hunters towards the relief materials immediately after the cyclone. When the relief programme was closed, male members of the family started moving towards nearer cities to find an income. Most of them started to pull rickshaws or to work as labourer in industries. They live at slum-environment to accumulate more money for their dependants; their out-migration from the family creates more social problems for their spouse as well. Accordingly, their spouse should take care of other family members and children. In most of the cases, those dependants move towards cities and and they also become migrants and start working there. However, it is evident that a lot of people do not bring their family and children and get married again. It introduces changes in local social structure. Furthermore, based on the income and asset distribution at the community level, this study developed societal cluster of migration and, correlating with previous disaster and census data, it introduces a new methodological tool for analysing disaster-migration nexus." [author's abstract]

  • Publication . Conference object . 2017
    Authors: 
    Tobias Schnelle; Adolf Schweer; Peter Schegner;
    Publisher: IEEE

    The increasing number of distributed energy resources, energy storage systems and controllable loads, summarized as decentralized actors (DAs), causes new challenges for grid operation and planning. At the same time, it leads to new capabilities of forming microgrids (MGs) with controllable generation, consumption and storage functionalities in public distribution systems. To utilize MGs for ensuring grid stability in critical situations, necessary communication technologies are cost intensive and have to meet high security and reliability requirements. Modular microgrids (MMGs), which are decoupled from the upstream grid by power electronic grid interconnectors, offer the chance to use grid frequency as cost efficient and reliable communication channel. This paper presents a novel approach to control MMGs by frequency variation. To demonstrate the potential of the concept, the MMG with its DAs is modeled in DIgSILENT PowerFactory and simulation results are depicted.

  • Open Access English
    Authors: 
    Giese, Lutz B.;
    Publisher: Technische Hochschule Wildau
    Country: Germany

    The greenhouse gases (GHG) carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) are considered mainly to be responsible for the additional anthropogenic greenhouse effect, the so-called “global warming”. In the private sector, the “Rational Use of Energy” can be a very effective tool (i) to reduce the greenhouse gas emissions, (ii) to decrease the annual energy costs and furthermore (iii) it prepares the integration of Renewable Energy Sources by saving conventional, mostly fossil energy. Aim of this paper is (i) to show that by applying energy saving measures, the primary energy demand and thus the individual (direct) carbon dioxide emission can be reduced in a relevant scale. (ii) It is to give laterally information about (ii.i) the energy market structure and (ii.ii) the legal backgrounds in the EU.

  • Authors: 
    Serguei Kondratenko; Leonard M. Rubin; Eric A. G. Webster;
    Publisher: IEEE

    This paper presents SIMS data for very high energy ion implantations of arsenic (1.9–8.0 MeV), boron (2.0–5.0 MeV), and phosphorus (4.0–8.0 MeV) from Axcelis’ PurionTM VXE implanter with comparison to TCAD simulation results. Arsenic is found to be highly sensitive to implant angle, requiring beam angle control better than 0.05°, and to be relatively insensitive to damage and is generally in good agreement with simulation. It is reported for the first time that the As profile for tilt/twist=1°/0° is more channeled than 0.5°/22°, indicating the significance of planar channeling for this condition even at tilt angles ≤1.0°. Boron is well described by the TCAD model except for a 2.0 MeV highly channeled implant where it underestimates the channeling. Phosphorus is found to be the most challenging to simulate with a general overestimation of the channeling tail.

  • Publication . Conference object . 2018
    Authors: 
    Laura Dente; Leila Guerriero; Nuno Carvalhais; Pedro Silva; Paula Soares; Paolo Ferrazzoli; Nazzareno Pierdicca;
    Publisher: SPIE

    A combined Position-Reflectometry Galileo receiver on board a low cost unmanned aerial platform (UAV) was developed in the framework of the Combined Positioning-Reflectometry Galileo Code Receiver for Forest Management project (COREGAL) with the main aims of evaluating the accurate positioning in areas where no GNSS ground infrastructures are available and of investigating the forest biomass mapping. In this context, the Soil and Vegetation Reflection Simulator (SAVERS) was employed to simulate GNSS-R data in order to analyze the GNSS-R sensitivity to biomass, to create a Look Up Table (LUT) of GNSS-R reflectivity and to carry out a biomass retrieval test. SAVERS simulated the mean power of the reflected GNSS-R signals by applying the integral bistatic equation taking into account the scattering contributions from soil and vegetation. It was shown that the GNSS-R sensitivity to forest biomass can be enhanced by filtering out the incoherent component of the signal, i.e. by using a long coherent integration time. A LUT was created by running SAVERS for a realistic range of the input parameters. Moreover, a GNSS-R synthetic dataset was generated for the case of a cork oak open forest in Portugal and a retrieval test was carried out. A neural network with two hidden layers was trained on the LUT and the forest biomass was estimated from the synthetic data. The biomass mean retrieval error was approximately 10 t/ha.