Muon and neutrino results from KGF experiment at a depth of 7000 hg/square cm

The KGF nucleon decay experiment at a depth of 7000 hg/sq cm has provided valuable data on muons and neutrinos. The detector comprised of 34 crossed layers of proportional counters (cross section 10 x 10 sq cm; lengths 4m and 6m) sandwiched between 1.2 cm thick iron plates can record tracks of charged particles to an accuracy of 1 deg from tracks that traverse the whole of the detector. A special two-fold coincidence system enables the detector to record charged particles that enter at very large zenith angles. In a live time of 3.6 years about 2600 events have been recorded. These events include atmospheric muons, neutrino induced muons from rock, stopping muons, showers and events which have their production vertex inside the detectors. The results on atmospheric muons and neutrino events are presented

Data from tests of a R4 airfoil in the Langley 0.3-meter transonic cryogenic tunnel

Aerodynamic data for the DFVLR R4 airfoil are presented in both graphic and tabular form. The R4 was tested in the Langley 0.3-Meter Transonic Cryogenic Tunnel (TCT) at Mach number from 0.60 to 0.78 at angles of attack from -2.0 to 8.0 degrees. The airfoil was tested at Reynolds numbers of 4, 6, 10, 15, 30, and 40 million based on the 152.32 mm chord

Modeling pressure oscillations in Ramjets

Pressure oscillations in ramjet engines are approximated as one-dimensional motions and treated within linear acoustics. The exhaust nozzle is represented by the admittance function for a short choked nozzle. New results have been obtained for the quasi-steady response of a normal shock wave in the diffuser. Acoustic fields in the inlet region and in the combustion chamber are matched to provide an analytical expression of the criterion for linear stability. Combustion processes are accommodated but not treated in detail. As examples, data are discussed for two liquid-fueled engines, one having axial dump and one having side dumps

Exploiting graphic processing units parallelism to improve intelligent data acquisition system performance in JET's correlation reflectometer

The performance of intelligent data acquisition systems relies heavily on their processing capabilities and local bus bandwidth, especially in applications with high sample rates or high number of channels. This is the case of the self adaptive sampling rate data acquisition system installed as a pilot experiment in KG8B correlation reflectometer at JET. The system, which is based on the ITMS platform, continuously adapts the sample rate during the acquisition depending on the signal bandwidth. In order to do so it must transfer acquired data to a memory buffer in the host processor and run heavy computational algorithms for each data block. The processing capabilities of the host CPU and the bandwidth of the PXI bus limit the maximum sample rate that can be achieved, therefore limiting the maximum bandwidth of the phenomena that can be studied. Graphic processing units (GPU) are becoming an alternative for speeding up compute intensive kernels of scientific, imaging and simulation applications. However, integrating this technology into data acquisition systems is not a straight forward step, not to mention exploiting their parallelism efficiently. This paper discusses the use of GPUs with new high speed data bus interfaces to improve the performance of the self adaptive sampling rate data acquisition system installed on JET. Integration issues are discussed and performance evaluations are presente

Preparation and evaluation of properties of cast metallic foams with regular inner structure

Lately we encounter still more new applications of metallic foams, as well as possible methods of their manufacture. These metallic materials have specific properties, such as large rigidity at low density, in some cases high thermal conductivity, capability to absorb energy, etc. The work is focused on the preparation of these materials using conventional casting technology, which ensures rapid and economically feasible method for production of shaped components. In the experimental part we studied conditions of casting of metallic foams with a regular structure made of ferrous and non-ferrous alloys. For thus obtained castings we evaluated the achieved microstructure and mechanical properties, which determine the possible use of these materials. The samples were subjected to compression tests, by which we investigated deformation behaviour of selected materials and determined the value of energy absorption.Web of Science6231646164

Electrophoretic deposition of gradated oxidation resistant coatings on tantalum-10 tungsten alloy

Material selection and electrophoretic deposition studies of high temperature oxidation resistant coatings on tantalum-10 tungsten allo

Izdelava poroznih kovinskih ulitkov

The article deals with the foundry methods of manufacturing porous metal; it is focused on the materials with a regular arrangement of internal cells. Currently. there are many fields dealing with the problem of porous metals by either optimizing the already known technologies, developing new ones or using porous metals. The production of a porous metal with a regular structure of cells and the possibility of its functional usage are the main subjects of this article. Due to their shapes, sizes and distribution of internal pores, cast porous metals exhibit various properties including reduced weight, sufficient strength, an ability to absorb impact energy, a possibility to conduct heat, etc., that allow a wide range of applications in the areas such as construction. transport or power engineering.Članek opisuje livarske metode izdelave poroznih kovin. Osredotoča se na materiale s pravilno urejenostjo notranjih celic. Trenutno se na mnogih področjih ukvarjajo s problemi poroznih kovin, bodisi z optimizacijo že znanih tehnologij, razvojem novih, ali njihovo uporabo. Glavni predmet članka je izdelava poroznih kovin s pravilno strukturo celic in možnostjo njihove uporabe. Porozni ulitki imajo zaradi svoje značilne oblike, velikosti in porazdelitve por različne specifične lastnosti, vključno z manjšo maso, zadovoljivo trdnostjo, sposobnostjo absorpcije udarne energije, prevajanja toplote itd. Vse to omogoča njihovo uporabo na različnih področjih, kot so konstrukcije, transport, inženiring prenosa energije in moči.Web of Science53114113

Atomic data from the Iron Project VII. Radiative dipole transition probabilities for Fe II

Relevant data is available at: http://www.astronomy.ohio-state.edu/~nahar/nahar_radiativeatomicdata/index.htmlOscillator strengths, line strengths and Einstein A-coefficients are obtained for a large number of dipole allowed (ΔS = 0) fine structure transitions in Fe II. Spectroscopic energies of the observed fine structure levels are employed in the transformation from LS coupled multiplet strengths to the individual fine structure lines. The transition probabilities are thus significantly improved in accuracy over those obtained with calculated energies. As part of the second phase of the Iron Project the present work is part of the effort to improve the accuracy and the utility of the Opacity Project data. The calculations correspond to a 83-state close coupling calculations for Fe II described by Nahar & Pradhan (1994). Comparison of present oscillator strengths and lifetimes is made with experimental values, and with those calculated by Kurucz; the present values show an overall better agreement with the experimental data. Radiative data is obtained for 21,589 dipole allowed fine structure transitions in Fe II.The work was supported by NASA (NAGW-3315) under the Long Term Space Astrophysics (LTSA) program and by a fellowship awarded by the College of Mathematical and Physical Sciences at the Ohio State University

Comparative study of analytical formulae for the fire resistance of steel beam-columns

peer reviewedThis paper investigates the difference between the buckling formulae published in the Eurocode 3 part 1.2 and the recommendations made in the final report of the Buckling Curves in Case of Fire (BCCF) research project. This study compares the critical temperatures obtained with both formulations to assess the impact on the fire endurance of steel columns subjected to axial compression and bending. An extensive comparison of the ultimate temperatures obtained with both formulations has been performed (382 profiles, buckling about the strong and weak axis, 12 column lengths, 6 M/N ratios and uniform and triangular bending moment distributions). Failure temperatures between 400°C and 860°C have been considered. The formulations are also compared with Finite Elements (F.E.) calculations performed for a S235 HEA 200 at 600ºC. This analysis shows that for buckling about the strong axis the BCCF method is better than the EC3 but for buckling about the weak axis the EC3 predicts failure temperatures closer to the F.E. model than the BCCF formulation. Finally, the ultimate temperatures predicted by the two formulations have also been compared with experimental results from the database SCOFIDAT. This comparison shows that there is no major difference between the two formulations for small and large bending moments. This study concludes that the EC3 and BCCF formulations are generally equivalent and that either formulation can be used