Global commitment towards sustainable energy

Energy is crucial to economic and social development and improves quality of life. However, fossil fuel energy produces greenhouse gases (GHGs) and cannot be sustained for a long time. It is essential to tackle these problems by moving towards renewable and sustainable energy. Some countries, including those in the Arabian Gulf region, are still in the appraisal stage of adopting different forms of renewable energy. This paper reviews the business potential and likely GHG reductions associated with adopting renewable energy in Oman. It is revealed that 1·9 Mt of annual carbon dioxide emissions could be cut by producing 10% of the country’s electricity from renewables. The paper further discusses the global sustainable energy commitment under the UN Framework Convention on Climate Change and reviews the 2030 targets of some countries that are high producers of GHGs. It is anticipated that if all these planned targets are achieved, the total sustainable energy contribution could grow by nearly 11 000 TWh by 2030. These plans provide guidance for those countries still preparing to submit their plans to the UN

Analysis of SEU Effects in Partially Reconfigurable SoPCs

Sterpone L, Margaglia F, Köster M, Hagemeyer J, Porrmann M. Analysis of SEU Effects in Partially Reconfigurable SoPCs. In: European Space Agency, Jet Propulsion Laboratory, USA. National Aeronautics and Space Administration, The University of Edinburgh. National Aeronautics and Space Administration, eds. Proceedings of NASA/ESA Conference on Adaptive Hardware and Systems (AHS-2011). Piscataway, NJ: IEEE; 2011: 129-136.Systems on Programmable Chips (SoPCs) are receiving an increasing interest from various application domains. Safety critical missions, driven by space and avionics applications, are especially attracted in using SoPCs due to low non-recurring engineering costs, reconfigurability and the large number of logic resources they provide. The capability of partial reconfiguration has recently become a promising approach to enhance the flexibility of a given system and to adapt and customize to different requirements. However, Single Event Upsets (SEUs) induced by radiation environment where space and avionics system operate, have a critical and catastrophic effect in these devices. In this paper, we propose a novel algorithm, which is able to identify critical SEUs corrupting the functionality of a SoPC using dynamic and partial reconfiguration. The algorithm is based on an analyzer able to interact with the dynamic system components containing partial reconfiguration modules, the communication infrastructure and the static region. Efficient critical SEUs estimation depends not only on the independent component mapping but also on the routing interaction between reconfigurable modules placed in different feasible positions. The analysis algorithm has been proven on a partially reconfigurable platform using different applications, besides it has been validated by means of fault injection campaigns of SEUs into SoPC's configuration memory. The experimental results demonstrated the effectiveness of the developed algorithm. Fault injection results have been accurately investigated and commented

Scaling study for SP-100 reactor technology

In this study, we explored several ways of extending SP-100 reactor technology to higher power levels. One approach was to use the reference SP-100 pin design and increase the fuel pin length and the number of fuel pins as needed to provide higher capability. The impact on scaling of a modified and advanced SP-100 reactor technology was also explored. Finally, the effect of using alternative power conversion subsystems, with SP-100 reactor technology was investigated. One of the principal concerns for any space-based system is mass; consequently, this study focused on estimating reactor, shield, and total system mass. The RSMASS code (Marshall 1986) was used to estimate reactor and shield mass. Simple algorithms developed at NASA Lewis Research Center were used to estimate the balance of system mass. Power ranges from 100 kWe to 10 MWe were explored assuming both one year and seven years of operation. Thermoelectric, Stirling, Rankine, and Brayton power conversion systems were investigated. The impact on safety, reliability, and other system attributes, caused by extending the technology to higher power levels, was also investigated. 6 refs., 4 figs., 3 tabs

The excess flux in the cosmic submillimeter background radiation and the primordial deuterium abundance

Recent measurements of the cosmic background radiation (CBR) show an enhanced flux in the submillimeter regime, compared to the spectrum of a 2.7 K blackbody. Thermal Comptonization of the relic radiation by a hot nonrelativistic plasma has long been known to produce distortions in the CBR spectrum, similar to what has now been observed. Heating of the primeval plasma to temperatures T {approximately} 10{sup 6} {minus} 10{sup 8} K could result from the injection of subcosmic ray protons at epoch z {approximately} 10--100. The intensity of the subcosmic ray flux that provide conditions needed to explain the submillimeter excess by thermal Comptonization also leads to the production of cosmologically significant amounts of deuterium in collisions between subcosmic ray protons and primordial protons and {alpha}-particles. However, the amount of lithium produced through {alpha}-{alpha} reactions is in conflict with the observed Li abundance. If lithium is depleted, for example, by processing through Population II stars, arguments for the baryon content of the universe based on primordial deuterium and He abundances are weakened. 12 refs., 1 fig., 1 tab

A database of fragmentation cross section measurements applicable to cosmic ray propagation calculations

A database of single particle inclusive fragment production cross section measurements has been established and is accessible over common computer networks. These measurements have been obtained from both published literature and direct communication with experimenters and include cross sections for nuclear beams on H, He, and heavier targets, and for H and He beams on nuclear targets, for energies >30 MeV/nucleon. These cross sections are directly applicable to calculations involving cosmic ray nuclear interactions with matter. The data base includes projectile, target, and fragment specifications, beam energy, cross section with uncertainty, literature reference, and comment code. It is continuously updated to assure accuracy and completeness. Also available are widely used semi-empirical formulations for calculating production cross sections and excitation functions. In this paper we discuss the database in detail and describe how it can be accessed. We compare the measurements with semi-empirical calculations and point out areas where improved calculations and further cross section measurements are required. 5 refs., 2 figs

JACEE long duration balloon flights

JACEE balloon-borne emulsion chamber detectors are used to observe the spectra and interactions of cosmic ray protons and nuclei in the energy range 1-100A TeV. Experience with long duration mid-latitude balloon flights and characteristics of the detector system that make it ideal for planned Antarctic balloon flights are discussed. 5 refs., 2 figs

Radiative forcing from the 1991 Mount Pinatubo volcanic eruption

Volcanic sulfate aerosols in the stratosphere produce significant long-term solar and infrared radiative perturbations in the Earth's atmosphere and at the surface, which cause a response of the climate system. Here we study the fundamental process of the development of this volcanic radiative forcing, focusing on the serendipitous eruption of Mount Pinatubo in the Philippines on June 15, 1991. We develop a spectral-, space-, and time-dependent set of aerosol parameters for two years after the Pinatubo eruption using a combination of SAGE II aerosol extinctions and UARS-retrieved effective radii, supported by SAM II, AVHRR, lidar and balloon observations. Using these data we calculate the aerosol radiative forcing with the ECHAM-4 general circulation model (GCM) for cases with climatological and observed sea surface temperature (SST), as well as with and without climate response. We find that the aerosol radiative forcing is not sensitive to the climate variations caused by SST or the atmospheric response to the aerosols, except in regions with varying dense cloudiness. The solar forcing in the near infrared contributes substantially to the total stratospheric heating. A complete formulation of radiative forcing should include not only changes of net fluxes at the tropopause, but the vertical distribution of atmospheric heating rates and the change of downward thermal and net solar radiative fluxes at the surface. These forcing and aerosol data are available for GCM experiments with any spatial and spectral resolution. (orig.)Available from FIZ Karlsruhe / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Surface Ocean CO2 Atlas (SOCAT) V6

The Surface Ocean CO2 Atlas (SOCAT) is a synthesis activity by the international marine carbon research community (>100 contributors). SOCAT version 6 has 23.4 million quality-controlled, surface ocean fCO2 (fugacity of carbon dioxide) observations from 1957 to 2017 for the global oceans and coastal seas. Calibrated sensor data are also available. Automation allows annual, public releases. SOCAT data is discoverable, accessible and citable. SOCAT enables quantification of the ocean carbon sink and ocean acidification and evaluation of ocean biogeochemical models. SOCAT represents a milestone in biogeochemical and climate research and in informing policy. 424 datasets Version 5: https://doi.pangaea.de/10.1594/PANGAEA.877863 Version 4: https://doi.pangaea.de/10.1594/PANGAEA.866856 Version 3: https://doi.pangaea.de/10.1594/PANGAEA.849770 Version 2: https://doi.org/10.1594/PANGAEA.81515