The basics of load tests for a computer cluster with a large number of GPUs (graphics processing units) distributed over the cluster’s nodes are presented and implemented as a program code. ...Information about the time delays in the transfer of data of different sizes among all GPUs in the system is collected as a result. Two modes of tests, ‘‘all to all’’ and ‘‘one to one,’’ are developed. In the first mode, all GPUs transfer data to all GPUs simultaneously. In the second mode, only the transfer between two GPUs proceeds at a single moment in time. Using test results obtained on the K60 computer cluster at the Keldysh Institute of Applied Mathematics, Russian Academy of Sciences, it is shown that the interconnector medium of the supercomputer is inhomogeneous in data transfer among the GPUs not only for transfer through the network, but also for the GPUs in a common node of the computer cluster.
This study is concerned with an analysis of seismicity and deep structure in the Transbaikalia along the 1-SB reference geophysical traverse. We have found a complex inhomogeneous structure of the ...crust and upper mantle. The crustal thickness varies between 40 km in the southeastern part of the traverse and in intermontane troughs in its northwestern part on the one hand and 48 km in mountain ranges. Strong variation also affects boundary velocities at the Moho, ranging from 8.4‒8.5 km/s for compressional waves and 4.9‒4.95 km/s for shear waves (especially in the southeastern part of the traverse) to lower values of 7.8‒8.0 km/s for compressional waves and 4.6‒4.7 km/s for shear waves in the area of the Baikal Rift Zone in the northwestern part of the traverse. A strongly inhomogeneous earth structure based on elastic wave velocities, Vp/Vs velocity ratios, and Poisson’s ratio was found for upper and middle crust at depths of 8‒20 km. It was also found that zones of higher seismicity tend to coincide with crustal blocks with inhomogeneous velocity structure based on differently polarized compressional and shear waves. Higher inhomogeneity in upper crust as inferred from elastic wave velocities and secondary earth parameters (Vp/Vs velocity ratios, the parameter K* = Vp/(γ ‒ 1), where γ = Vp/Vs, and Poisson’s ratio (σ)) characterize the area of the Baikal Rift Zone in an immediate vicinity of the great Muya earthquake of 1957 with
М
= 7.6. As well, several other deep zones of inhomogeneity have been identified along the traverse line based on anomalies of Р and S velocities and secondary earth parameters that correlate to varying degrees with seismically active areas based on multiyear instrumental observations. We have identified an unambiguous relationship of large inhomogeneous zones in the Transbaikalia crust with stress buildup and stress release in the shape of large earthquakes, thus substantiating the intermediate-term prediction of catastrophic events.
Predicting the start time of a task without placing the task in a task queue is very difficult in modern data centers. The article proposes to improve the previously created forecasting tool through ...the use of more modern software interfaces to the SchedMD queuing system (Slurm), as well as the use of various mathematical forecasting methods to predict the moment of task launch. To compare and evaluate machine learning models, we selected a SWF file with task execution history data on the University of Luxembourg computing cluster with 59 715 tasks. The following methods were investigated: linear regression with L2 regularization, support vector machine, random forest, LightGBM, CatBoost, LightGBM with parameter optimization, CatBoost with parameter optimization. To check the correctness of the prediction, a test bench was built based on the Slurm simulator (SUNY Center for Computational Research at the University at Buffalo, USA), which works based on executing tasks and organizing a queue of saved logs.
Random transgene integration is a powerful tool for developing new genome-wide screening approaches. These techniques have already been used for functional gene annotation by transposon-insertion ...sequencing, for identification of transcription factor binding sites and regulatory sequences, and for dissecting chromatin position effects. Precise localization of transgenes and accurate artifact filtration are essential for this type of method. To date, many mapping assays have been developed, including Inverse-PCR, TLA, LAM-PCR, and splinkerette PCR. However, none of them is able to ensure localization of both transgene’s flanking regions simultaneously, which would be necessary for some applications. Here we proposed a cheap and simple NGS-based approach that overcomes this limitation. The developed assay requires using intentionally designed vectors that lack recognition sites of one or a set of restriction enzymes used for DNA fragmentation. By looping and sequencing these DNA fragments, we obtain special data that allows us to link the two flanking regions of the transposon. This can be useful for precise insertion mapping and for screening approaches in the field of chromosome engineering, where chromosomal recombination events between transgenes occur in a cell population. To demonstrate the method’s feasibility, we applied it for mapping SB transposon integration in the human HAP1 cell line. Our technique allowed us to efficiently localize genomic transposon integrations, which was confirmed via PCR analysis. For practical application of this approach, we proposed a set of recommendations and a normalization strategy. The developed method can be used for multiplex transgene localization and detection of rearrangements between them.
Tolerance of the chest-to-back accelerations (+Gx) at the peak value of 6.7 g was evaluated in two Soyuz crew members during the ballistic landing after an off-nominal launch. The G-tolerance of crew ...member 1 (CM1) when passing through the dense layers of the atmosphere was assessed as good based on analysis of reported subjective sensations and results of objective physiological investigations: the physiological reactions of the body to the action of g-force were of a moderate nature; no critical signs limiting G-tolerance were noted. The G-tolerance of crew member 2 (CM2) was assessed based on analysis of objective physiological information only, which allowed us to consider it good. CM1 highly appreciated the experience gained during flight preparation, including the experience of centrifuge (CF) spins, which enabled him to act professionally in an emergency situation. The tolerance of g-force with a maximum value of 6.7 units by the
ISS
crew after the off-nominal Soyuz launch was assessed as good.
Small-signal and noise GaAs pHEMT modeling techniques that include analytical extraction followed by optimization are demonstrated. The following measurement processing steps were carried out before ...the parameter extraction: de-embedding, data smoothing and selecting the bias mode appropriate for the extraction of parasitic resistances and inductances. A low-noise amplifier operating in 5G frequency band was designed using the resulting model. A comparison between simulation and measurements of noise factor and S-parameters of the obtained low-noise amplifier is presented.
Evolution of the configuration database design Salnikov, A.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2006, Letnik:
559, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The
BaBar experiment at SLAC successfully collects physics data since 1999. One of the major parts of its on-line system is the configuration database which provides other parts of the system with ...the configuration data necessary for data taking. Originally the configuration database was implemented in the Objectivity/DB ODBMS. Recently
BaBar performed a successful migration of its event store from Objectivity/DB to ROOT and this prompted a complete phase-out of the Objectivity/DB in all other
BaBar databases. It required the complete redesign of the configuration database to hide any implementation details and to support multiple storage technologies. In this paper we describe the process of the migration of the configuration database, its new design, implementation strategy and details.
A method for evaluation of the performance of the disk subsystem of a data buffering and transmission system and results of experimental studies of the performance of the disk subsystem according to ...the developed method are presented. A conclusion is drawn on the reasonability of the use of hard-disk drives that provide the required read/write rates with a sufficiently high level of reliability in prospective development of the modern high-capacity NearLine SAS (NL-SAS).
It is proposed a computational model for the spatial cracks formation of the first, second and third types in reinforced concrete structures under the action torsion with bending, based on working ...assumptions and solving equations, with allowance for physical nonlinearity, deplaning cross sections, prestressing in the longitudinal and transverse reinforcement and the influence of the local stress field. Solving equations are constructed in a special way, so that their system does not become decaying for functions of many variables with the Lagrange multipliers use for finding the minimum generalized load corresponding to the spatial crack formation of the first, second and third types and the coordinates of their formation points. It is obtained experimental data for checking the proposed design model, including the values of the general crack-forming load, the coordinates of the points of crack formation along the axes (x; y, z); cracks and angles of their tilt; distance between cracks at different levels of cracking; the width of the opening of the spatial cracks along the entire helical-shaped line; angles of twisting, deflections, deformation of concrete and reinforcement.
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