parMERASA – multicore execution of parallelised hard real-time applications supporting analysability

Abstract-Engineers who design hard real-time embedded systems express a need for several times the performance available today while keeping safety as major criterion. A breakthrough in performance is expected by parallelizing hard real-time applications and running them on an embedded multi-core processor, which enables combining the requirements for high-performance with timing-predictable execution. parMERASA will provide a timing analyzable system of parallel hard real-time applications running on a scalable multicore processor. parMERASA goes one step beyond mixed criticality demands: It targets future complex control algorithms by parallelizing hard real-time programs to run on predictable multi-/many-core processors. We aim to achieve a breakthrough in techniques for parallelization of industrial hard real-time programs, provide hard real-time support in system software, WCET analysis and verification tools for multi-cores, and techniques for predictable multi-core designs with up to 64 cores

Cu–(Ni–Co–Au)-bearing massive sulfide deposits associated with mafic–ultramafic rocks of the Main Urals Fault, South Urals: Geological structures, ore textural and mineralogical features, comparison with modern analogs

Cu-rich massive sulfide deposits associated with mafic–ultramafic rocks in the southern portion of the Main Urals Fault (MUF) are characterized by variable enrichments in Ni (up to 0.45 wt.%), Co (up to 10 wt.%) and Au (up to 16 ppm in individual hand-specimens). The Cu (Ni–Co)-rich composition of MUF deposits, as opposed to the Cu (Zn)-rich composition of more eastward massive sulfide deposits of broadly similar age along the western flank of the Magnitogorsk arc, reflects the abundance of seafloor-exposed, Ni–Co-rich ultramafic rocks in the most external portion of the Early-Devonian Magnitogorsk forearc. Morphological, textural, and compositional differences between individual deposits are interpreted to be the result of the sulfide deposition style and, in part, of the original subseafloor lithology. One deposit produced by dominantly on-seafloor hydrothermal processes is characterized by pyrite–marcasite>>pyrrhotite, not so low Zn grades (occasionally up to 2 wt.%), abundant clastic facies and periodical superficial oxidation. Deposits produced by dominantly subseafloor hydrothermal processes are characterized by pyrrhotite>pyrite, very low Zn (generally < to << 0.1 wt.%), volumetrically minor clastic facies, and multi-layer deposit morphology. Very low Ni/Co ratios in the on-seafloor deposit may indicate a dominant metal contribution from a mafic rather than ultramafic source. The sulfide mineralization was associated with extensive hydrothermal alteration of the host ultramafic and mafic rocks, leading to formation of abundant talc, talc–carbonate and chlorite rocks.Occurrence of large volumes of such altered lithotypes in ophiolitic belts may be considered as a potential searching criteria for MUF-type (Cu, Co, Ni)-deposits. In spite of the contrasting geodynamic environment, geological, geochemical, textural and mineralogical peculiarities of the MUF deposits in many respects are similar to those of ultramafic-hosted massive sulfide deposits along the Mid-Atlantic Ridge. In geological time, supra subduction-zone settings appear to have been more effective than mid-ocean ridge settings for preservation of ultramafic-hosted massive sulfide deposits

Peculiarities of some mafic-ultramafic- and ultramafic-hosted massive sulfide deposits fom the Main Uralian Fault Zone, southern Urals

Some Cu-rich, mafic-ultramafic- and ultramafic-hosted massive sulfide deposits from the southern segment of the Main Uralian Fault Zone (Ivanovka and Ishkinino deposits, southern Urals) show unusual characteristics. Their major features include: (i) relatively high Co (Ni, An), very low Zn and negligible Pb grades; (ii) a pyrrhotite-dominated mineralization, locally characterized by the presence of open- latticework aggregates of lamellar pyrrhotite with Mg-saponite Mg-chlorite and carbonate matrix; (iii) hydrothermal alteration of ultramafic host rocks into talc carbonate quartz chlorite and of mafic host rocks into chloritites; (iv) the presence of clastic facies with reworked sulfide and ultramafic or mafic components; (v) the widespread occurrence of sulfide-associated chromite; (vi) the specific mineralogy of Co, Ni, Fe and As, including sulfoarsenides, mono- and diarsenides, and Co-rich pentlandite and pyrite; (vii) the supra-subduction -zone geochemical signature of the host serpentinites and volcanic rocks. Although some of these features have been separately reported in certain modem ocean-seafloor and ophiolite-hosted fossil deposits, a true equivalent has yet to be found. Based on recognized partial analogies with a few modem seafloor examples, the arc tholeiitic-boninitic geochemical signature of sulfide-associated volcanic rocks and the highly refractory compositions of sulfide-hosted chromite relicts, the studied deposits are believed to have formed by seafloor-subseafloor hydrothermal processes in an oceanic island arc setting. Possible tectonostratigraphic correlation of sulfide-associated units with infant, non-accretionary arc volcanic units of the adjacent Magnitogorsk oceanic island-arc system suggests formation of the studied deposits during the earliest stages of Devonian subduction-related volcanism

Вязкость криолитоглиноземных расплавов промышленного состава

The study covers the viscosity of NaF–AlF3–CaF2–Al2O3 conventional cryolite-alumina melts with a cryolite ratio CR = 2.3 depending on the CaF2, Al2O3 content and temperature. The viscosity of cryolite-alumina electrolyte samples prepared under laboratory conditions and electrolyte samples of industrial electrolytic cells was measured by the rotary method using the FRS 1600 rheometer («Anton Paar», Austria). The laminar flow region of the melt determined according to the dependence of viscosity on shear rate at a constant temperature was 10–15 s–1 for all the studied samples. The temperature dependence of cryolite-alumina melt viscosity was measured at a shear rate of 12 ± 1 s–1 in the temperature range from liquidus to 1020 °C. It was shown that the change in the viscosity of all samples in the investigated temperature range (50–80 °С) can be described by a linear equation. The average temperature coefficient of linear equations describing the viscosity of cryolite-alumina electrolytes prepared in laboratory conditions was 0.005 mPа· s/°С, which is 2 times less compared to industrial cell electrolytes. Thus, the change in the viscosity of industrial cell electrolytes with increasing temperature is more significant. Both alumina and calcium fluoride additives increase the cryolite melt viscosity. The viscosity of samples prepared with the conventional composition NaF–AlF3–5%CaF2–4%Al2O3 (CR = 2.3) is equal to 3.11 ± 0.04 mPа· s at an electrolysis operating temperature of 960 °C, while the viscosity of industrial cell electrolytes with the same cryolite ratio is 10–15 % higher and falls in the range of 3.0–3.7 mPа· s depending on the electrolyte composition.Проведены исследования вязкости криолитоглиноземных расплавов промышленного состава NaF–AlF3–CaF2–Al2O3 с криолитовым отношением КО = 2,3 в зависимости от содержания CaF2, Al2O3 и температуры. Вязкость образцов криолитоглиноземных электролитов, приготовленных в лабораторных условиях, и образцов электролитов промышленных электролизных ванн измеряли ротационным методом с использованием реометра FRS 1600 («Anton Paar», Австрия). Область ламинарного течения расплава, определенная по зависимости вязкости от скорости сдвига при постоянной температуре, составила 10–15 с–1 для всех исследованных образцов. Измерения температурной зависимости вязкости криолитоглиноземных расплавов проводили при скорости сдвига 12 ± 1 с–1 в температурном интервале от ликвидуса до 1020 °С. Показано, что изменение вязкости всех образцов в исследуемом температурном интервале (50–80 °С) можно описать линейным уравнением.Средний температурный коэффициент линейных уравнений, описывающих вязкость криолитоглиноземных электролитов, приготовленных в лабораторных условиях, составил 0,005 мПа·с/°С, что в 2 раза меньше, чем у электролитов промышленных ванн. Таким образом, изменение вязкости электролитов промышленных ванн с повышением температуры – более существенное. Добавки как глинозема, так и фторида кальция повышают вязкость криолитового расплава. Вязкость приготовленных образцов промышленного состава NaF–AlF3–5%CaF2–4%Al2O3 (КО = 2,3) равна 3,11 ± 0,04 мПа·с при рабочей температуре электролиза 960 °С, а вязкость электролитов промышленных ванн с таким же криолитовым отношением выше на 10–15 % и лежит в интервале 3,0–3,7 мПа·с в зависимости от состава