Stationary rotation of the unbalanced rotor with the liquid autobalancing device under action of external friction forces

Influence of external friction forces on rotation of the rotor with the liquid autobalancing device is considered. The liquid in the balancing chamber at stationary movement rotates together with the rotor as solids. Analytical expressions for deflection of the shaft, unbalance of the system and the necessary rotating moment from the engine providing rotation with set speed are received

Stationary rotation stability of unbalanced rotor with autobalancing device with liquid on flexible shaft

The condition of rotor rotation stability with liquid autobalancing device consisting of chamber, float and incompressible homogeneous liquid filling the space between them has been obtained. The restoring force and forces of internal and external friction take effect on the rotor. The latter depend linearly respectively on strain rate and absolute velocity of rotor connection point to the shaf

Investigation of Input Signal Curve Effect on Formed Pulse of Hydraulic-Powered Pulse Machine

Well drilling machines should have as high efficiency factor as it is possible. This work proposes factors that are affected by change of input signal pulse curve. A series of runs are conducted on mathematical model of hydraulic-powered pulse machine. From this experiment, interrelations between input pulse curve and construction parameters are found. Results of conducted experiment are obtained with the help of the mathematical model, which is created in Simulink Matlab

Распределенная отказоустойчивая платформа управления для программно-конфигурируемых сетей

The architecture of the high availability distributed control plane for SDN/OpenFlow networks are considered. High availability is achieved by redundancy of controller instances, active switch-controller communications, computing resources and tools for a controller instance failure and overloading detection and recovery. The proactive backup controller allocation algorithm which allows to minimize the time to repair in the case of a single controller instance failure is discussed. The algorithm for controller load-balancing allows dynamically reconfigure the control plane with a minimum number of switch control transfer operations to avoid controller instance overloading. The initial experimental results of the proposed algorithms for the HA distributed SDN control plane are described.В рамках исследования рассматривается проблема обеспечения отказоустойчивости распределенной платформы управления для программно-конфигурируемых сетей. Целью исследования является разработка архитектуры и принципов организации отказоустойчивой распределенной платформы управления для ПКС. Отказоустойчивость распределенной платформы управления ПКС достигается за счет резервирования контроллеров, резервирования активных соединений между коммутатором и несколькими контроллерами, резервирования вычислительных ресурсов и использования дополнительных программных инструментов для обнаружения отказов, предотвращения перегрузок и восстановления управления сетью. В работе приводится алгоритм распределения управления коммутаторами между контроллерами платформы управления, выбора резервных контроллеров для каждого коммутатора, что позволяет минимизировать время восстановления в случае одиночных отказов контроллеров. Алгоритм балансировки нагрузки между контроллерами позволяет динамически переконфигурировать платформу управления с минимальным количеством операций передачи управления коммутаторами, чтобы предотвратить перегрузку контроллера. Представлены результаты экспериментального исследования предложенных алгоритмов

Optimization of hole generation in Ti/CFRP stacks

The article aims to describe methods for improving the surface quality and hole accuracy in Ti/CFRP stacks by optimizing cutting methods and drill geometry. The research is based on the fundamentals of machine building, theory of probability, mathematical statistics, and experiment planning and manufacturing process optimization theories. Statistical processing of experiment data was carried out by means of Statistica 6 and Microsoft Excel 2010. Surface geometry in Ti stacks was analyzed using a Taylor Hobson Form Talysurf i200 Series Profilometer, and in CFRP stacks - using a Bruker ContourGT-K1 Optical Microscope. Hole shapes and sizes were analyzed using a Carl Zeiss CONTURA G2 Measuring machine, temperatures in cutting zones were recorded with a FLIR SC7000 Series Infrared Camera. Models of multivariate analysis of variance were developed. They show effects of drilling modes on surface quality and accuracy of holes in Ti/CFRP stacks. The task of multicriteria drilling process optimization was solved. Optimal cutting technologies which improve performance were developed. Methods for assessing thermal tool and material expansion effects on the accuracy of holes in Ti/CFRP/Ti stacks were developed

Optical and photoelectron spectroscopy studies of KPb2Cl 5 and RbPb2Cl5 laser crystals

The paper presents the results of experimental study of electronic structure of RbPb2Cl5 and KPb2Cl5 laser crystals performed by the optical and photoelectron spectroscopy methods. On the basis of the optical absorption and low-temperature reflection spectra of these crystals we have determined the energy positions of the edges of the low-energy tail of the host absorption, the positions of the first excitonic absorption peaks, and exciton binding energies. The bandgap widths of these crystals at 8 K were estimated as Eg = 4.83 and 4.79 eV, respectively. Qualitative and quantitative analysis of RbPb2Cl 5 and KPb2Cl5 crystals were made on the basis of the core states photoelectron spectra. The elemental composition of the (0 0 1) surfaces of the crystals, the chemical state of the host atoms, the electronic structure of the valence band of the crystals were discussed on the basis on the spectroscopic data. © 2012 Elsevier B.V. All rights reserved

Conformation of surface exposed N-terminus part of bacteriorhodopsin studied by transferred NOE technique

AbstractInteraction of the monoclonal antibody A5 raised against native bacteriorhodopsin (BR) with the synthetic peptide pGlu1-Ala-Gln-Ile-Thr-Gly-Arg7-NH2, corresponding to the amino acid sequence 1–7 was studied by transferred nuclear Overhauser effect (TRNOE) spectroscopy. The denaturing reagents and the specially designed pulse sequences which eliminate broad signals from the TRNOE spectra were used to favour evaluation of the TRNOE peaks. On the basis of the data obtained, the conformation of peptide bound with A5 was calculated. A model of the mutual arrangement of bacteriorhodopsin N-terminus and the first transmembrane α-helical segment 8–32 was proposed

Relationship Between Indices of Oxidative Stress, Endothelial Dysfunction and Chaperone Activity and the Severity of Coronary Atherosclerosis

The aim of this research was to study the relationship between the indices of oxidative stress, endothelial dysfunction and chaperone activity of proteins with the severity of coronary atherosclerosis. In patients with coronary heart disease, we found gender-related differences in the severity of coronary atherosclerosis. Significant differences in the indices of oxidative stress, endothelial dysfunction and chaperone activity were revealed depending on the severity of coronary atherosclerosis and the type of atherosclerotic lesion. The determination of studied parameters can serve as a good indicator of the severity of coronary atherosclerosis

Verification of zinc role in pathophysiology of chronic obstructive pulmonary disease

Aim. Determination of the level of zinc and its fractions, as well as the enzyme neutrophilic elastase and albumin in persons suffering from chronic obstructive pulmonary disease (COPD), as well as smoking actively and passively. Materials and methods. The study involved 30 patients with a diagnosis of COPD and 90 healthy persons (60 of them smoking at the present time, 30 - no) who underwent spirometry and determination of zinc levels and its pools, albumin, and neutrophil elastase. All data are subject to statistical processing. Results. It is determined that the studied parameters differ significantly in the groups of smokers with COPD, healthy smokers and non-smokers, and correlate with the volume of forced exhalation for 1 second as a percentage of the due. Conclusion. The revealed regularities make it possible to consider the indicator "share of bound zinc fraction" introduced in the study as a screening criterion in diagnosing COPD in smokers

Phase IIb randomized trial of adjunct immunotherapy in patients with first-diagnosed tuberculosis, relapsed and multi-drug-resistant (MDR) TB

Placebo-controlled, randomized, phase 2b trial was conducted in 34 adults comprising 18 first-diagnosed (52.9%), 6 relapsed (17.6%), and 10 MDR-TB (29.4%) cases to investigate the safety and efficacy of an oral immune adjunct (V5). The immunotherapy (N = 24) and placebo (N = 10) arms received once-daily tablet of V5 or placebo for one month in addition to conventional anti-TB therapy (ATT) administered under directly observed therapy (DOT)