Survey on software tools that implement deep learning algorithms on intel/x86 and IBM/Power8/Power9 platforms

Neural networks are becoming more and more popular in scientific field and in the industry. It is mostly because new solutions using neural networks show state-of-the-art results in the domains previously occupied by traditional methods, eg. computer vision, speech recognition etc. But to get these results neural networks become progressively more complex, thus needing a lot more training. The training of neural networks today can take weeks. This problems can be solved by parallelization of the neural networks training and using modern clusters and supercomputers, which can significantly reduce the learning time. Today, a faster training for data scientist is essential, because it allows to get the results faster to make the next decision. In this paper we provide an overview of distributed learning provided by the popular modern deep learning frameworks, both in terms of provided functionality and performance. We consider multiple hardware choices: training on multiple GPUs and multiple computing nodes. © The Authors 2019.Council on grants of the President of the Russian Federation: MK-2330.2019.9You can use a special version of Caffe, NVCaffe, which is supported by NVidia. This version was created specifically for the use of several GPUs. User instructions can be found in [35].For NVidia, MXNet is supported by Nvidia Cloud. MXNet also has support for CUDA and CuDNN.The results described in this paper were obtained with the financial support of the grant from the Russian Federation President Fund (MK-2330.2019.9)

Multifrequency dial sensing of the atmospheric gaseous constituents using the first and second harmonics of a tunable CO2 laser radiation

The results of field measurements of concentration of some gaseous components of the atmosphere along the paths, in Sofia, Bulgaria, using a gas analyzer based on the use of a CO2 laser radiation frequency-doubled with ZnGeP2 monocrystals are presented. The gas analyzer is a traditional long path absorption meter. Radiation from the tunable CO2 laser of low pressure and from an additional He-Ne laser is directed to a colliminating hundredfold Gregori telescope with a 300 mm diameter of the principal mirror. The dimensions of the mirrors of a retroreflector 500 x 500 mm and a receiving telescope allow one to totally intercept the beam passed through the atmospheric layer under study and back

Effect of pulse flows of charged particles on the structure and mechanical properties of metals

We investigate the effect of pulse flows of hydrogen, helium, and hydrogen-helium plasma of a specific power of 20-30 GW/m² on the surface structure and mechanical properties of vanadium, niobium, and Kh16N15M3B and Kh18N10T austenitic stainless steelsyesBelgorod State Universit

Limited Thermal Conductance of Metal-Carbon Interfaces

The thermal conductance for a series of metal-graphite interfaces has been experimentally measured with time-domain thermoreflectance (TDTR). For metals with Debye temperatures up to ∼400 K, a linear relationship exists with the thermal conductance values. For metals with Debye temperatures in excess of ∼400 K, the measured metal-graphite thermal conductance values remain constant near 60 MW m−2 K−1. Titanium showed slightly higher conductance than aluminum, despite the closeness of atomic mass and Debye temperature for the two metals. Surface analysis was used to identify the presence of titaniumcarbide at the interface in contrast to the aluminum and gold-carbon interfaces (with no detectablecarbide phases). It was also observed that air-cleaved graphite surfaces in contact with metals yielded slightly higher thermal conductance than graphite surfaces cleaved in vacuo. Examination of samples with scanning electron microscopy revealed that the lack of absorbed molecules on the graphite surfaceresulted in differences in transducer film morphology, thereby altering the interface conductance.Classical molecular dynamic simulations of metal-carbon nanotube thermal conductance values were calculated and compared to the TDTR results. The upper limit of metal-graphite thermal conductance is attributed to the decreased coupling at higher frequencies of the lighter metals studied, and to the decreased heat capacity for higher vibrational frequency modes

Optical pump–terahertz probe study of HR GaAs:Cr and SI GaAs:El2 structures with long charge carrier lifetimes

The time dynamics of nonequilibrium charge carrier relaxation processes in SI GaAs:EL2 (semi-insulating gallium arsenide compensated with EL2 centers) and HR GaAs:Cr (high-resistive gallium arsenide compensated with chromium) were studied by the optical pump–terahertz probe technique. Charge carrier lifetimes and contributions from various recombination mechanisms were determined at different injection levels using the model, which takes into account the influence of surface and volume Shockley–Read–Hall (SRH) recombination, interband radiative transitions and interband and trap-assisted Auger recombination. It was found that, in most cases for HR GaAs:Cr and SI GaAs:EL2, Auger recombination mechanisms make the largest contribution to the recombination rate of nonequilibrium charge carriers at injection levels above ~(0.5–3)·1018 cm−3, typical of pump–probe experiments. At a lower photogenerated charge carrier concentration, the SRH recombination prevails. The derived charge carrier lifetimes, due to the SRH recombination, are approximately 1.5 and 25 ns in HR GaAs:Cr and SI GaAs:EL2, respectively. These values are closer to but still lower than the values determined by photoluminescence decay or charge collection efficiency measurements at low injection levels. The obtained results indicate the importance of a proper experimental data analysis when applying terahertz time-resolved spectroscopy to the determination of charge carrier lifetimes in semiconductor crystals intended for the fabrication of devices working at lower injection levels than those at measurements by the optical pump–terahertz probe technique. It was found that the charge carrier lifetime in HR GaAs:Cr is lower than that in SI GaAs:EL2 at injection levels > 1016 cm−3.В ст. ошибочно: Irina A. Kolesnikov

NUCLOTRON CONTROL SYSTEM

Abstract The superconducting synchrotron, named the Nuclotron is based on miniature iron-shaped field SC-magnets. It was put into operation in March 1993 at the Laboratory of High Energies of the Joint Institute for Nuclear Research in Dubna. Eleven runs of the new accelerator have been performed by the present time.The Nuclotron Control System (NCS) project, which is still under development, started in 1992 and has provided an efficient support for the machine commissioning through all its phases. This paper presents the current status of the whole system and some details of cryogenics, beam injection, and main power supplies subsystems

Влияние социальных факторов, клинических характеристик и коморбидных нарушений на качество жизни пациентов с головной болью напряжения

Here we present the results of our study of the influence of clinical and social parameters as well as co-morbidities (as anxiety, depression, sleep disturbances) on the health related quality of life of 95patients with the most often met primary cephalgias — tension type headache. We used MOS-SF36 (Medical Outcomes Study Short Form-36) as the main instrument to measure health related quality of life. Significant influence of anxiety and depression on the quality of life in patients with both frequent episodic and chronic tension type headache was reported. Anxiety in these patients was mostly associated with psychic health, general health and vitality. In patients with chronic tension type headaches depression was associated with physical functioning; in those with frequent episodic tension type headaches — with social functioning and role functioning due to emotional sate.В статье приводятся результаты исследования влияния клинических параметров, социальных факторов и коморбидных нарушений (тревога, депрессия, нарушения сна) на качество жизни 95 больных с наиболее часто встречающейся формой первичных цефалгий - головной болью напряжения. Для исследования качества жизни в работе использовался Medical Outcomes Study Short Form-36 (MOS SF-36). Определено значительное влияние на качество жизни пациентов с хронической и эпизодической частой головной болью напряжения коморбидных нарушений (тревоги и депрессии). Тревога у этих пациентов в большей степени связана с психическим здоровьем, жизненной активностью и общим состоянием здоровья. У пациентов с хроническими головными болями напряжения депрессия связана с физическим функционированием, при частых эпизодических головных болях напряжения - с социальным функционированием и ролевым функционированием, обусловленным эмоциональным состоянием