Complex for Modeling the Reliability of Reactor Plant Systems by the Monte Carlo Method

The article considers the main models incorporated in the developed software package for modeling reliability indicators of nuclear reactor unit (RF) complex technical systems by the Monte Carlo method. Approaches to organization of system state determination on the layout basis into groups, principles of accounting for dependent failures and incomplete recovery are described

Confounding factors in ultrasound liver elastography. Part 1. General provisions and methodological errors

The aim of the study is a systematic analysis of literature data on the effect of methodological factors, artifacts, as well as external influences and features of the state of the organism on the results of ultrasonic elastography of the liver. Two-dimensional shear wave elastography is a highly accurate method for assessing the degree of liver fibrosis, provided that the study methodology is strictly followed, however, the influence of measurement disturbances should be taken into account. Confounding factors lead to an erroneous change in the liver stiffness from insignificant, within 5-10%, to considerable, catastrophically distorting the assessment of the degree of liver fibrosis. Confounding factors include three main groups: 1) methodologically determined, as well as physical artifacts and equipment features; 2) internal (endogenous) and 3) external (exogenous). The first group of confounding factors includes: non-observance by the operator of the standard rules for manipulating the probe, positional features of the patient, insufficient size of the window area of the area of interest, incorrect location of the area of interest, lack of adequate breath holding by the patient or the performing of his/her movements, insufficient number of measurements, large spread of recorded values, transmission pulsations from the heart and large vessels, features of the equipment used, physical essence of the elastographic method and artifacts

Rotavirus infection in children: clinical and laboratory features and catamnesis

Purpose is to study the clinical, laboratory and instrumental characteristics of the course of rotavirus infection in children up to 3 years in the acute phase and during the convalescence period. Material and methods. A clinical, laboratory and instrumental examination of 320 children up to 3 years with moderate to severe rotavirus infection. Results. The presence of long-term persistence of rotavirus recovering from rotavirus infection. Identified functional disorders of the digestive system in the acute period and the period of convalescence in children up to 3 years with rotavirus infection. Conclusion. For a long period (up to 3 months), almost half of patients may experience intestinal dysfunction, possibly related to the long-term persistence of rotavirus

Synthesis and oxidation of 2-furyl-4-R-substituted and furo[3,2-c]- condensed 1,2,3,4-tetrahydro-1,10-phenanthrolines and quinolines

2-Furyl-4-substituted and furo[2,3-c]-condensed 1,2,3,4-tetrahydro-1,10- phenanthrolines were obtained for the first time from 8-aminoquinolines using the Povarov reaction. Various oxidizing agents were shown to effect the elimination of the substituent at C(4) with subsequent aromatization of the tetrahydroquinoline fragment. © 2009 Springer Science+Business Media, Inc

Improvement of power supply reliability by means of remote control of the automatic repeated switching-on of sectionalizing circuit-breakers

An important direction in improving the technical and economic level of technologies and agricultural production machinery is to ensure high reliability of power supply. Power interruptions cause damage to both agricultural consumers and power supply organizations. Therefore, obtaining on-line information about the occurrence of emergency operating conditions, and, therefore, minimizing the time for making operational decisions on their elimination, is an urgent task. Known methods and technical control means are complex, expensive and not effective enough. At the same time, they have both advantages and disadvantages. In this respect, it is very important to work out efficient technical means of remote control of power line sectionalizing circuit-breakers of the agro-industrial complex on the basis of innovative methods of monitoring. The proposed control method is implemented in a device for remote control of the overhead line circuit-breaker operation based on an analog-to-digital converter, with subsequent software-based processing of the received data on a computer. This method implementation of circuit breaker opening remote control will improve power supply reliability of agricultural consumers

Infectious mononucleosis in children: clinical and laboratory rationale and economic efficiency of application of immunocorrectors

Objective: to select the optimal, clinically and economacally effective immunocorrector for the treatment of immune-EBV — mononucleosis in children. Materials: 400 patients with primary Epstein — Barr virus infection aged 1 to 14 years. Results. The therapy by cycloferon of primary Epstein — Barr virus infection observed a statistically significant reduction in the length of stay of patients in hospital, on average, 3 bed-days. Inclusion of cycloferon, viferon in the treatment of infectious mononucleosis, reduces the severity and duration of symptoms of intoxication, the temperature reaction, hepatotoxicity, splenomegaly, lymphoproliferative syndrome. Against the background of cycloferon lower incidence of post-infection anemia was observed. Conclusion. The inclusion of immunocorrectors into therapeutic interventions in primary Epstein — Barr virus infection has been clinically and economically proved

Synthesis and oxidation of 2-furyl-4-R-substituted and furo[3,2-c]- condensed 1,2,3,4-tetrahydro-1,10-phenanthrolines and quinolines

2-Furyl-4-substituted and furo[2,3-c]-condensed 1,2,3,4-tetrahydro-1,10- phenanthrolines were obtained for the first time from 8-aminoquinolines using the Povarov reaction. Various oxidizing agents were shown to effect the elimination of the substituent at C(4) with subsequent aromatization of the tetrahydroquinoline fragment. © 2009 Springer Science+Business Media, Inc

Cycloaddition of furfurylamines to maleic anhydride and its substituted derivatives

The regio- and stereoselectivity of the [4+2] cycloaddition of maleic, citraconic, dichloromaleic, and dibromomaleic anhydrides to difurfuryl amines and secondary furfurylamines were studied. N-Furfuryl-, N-phenyl-, and N-benzylhexahydrooxoepoxyisoindole-7-carboxylic acids were synthesized. An approach was developed for obtaining hexahydroepoxyoxoisoindole-7-carboxylic acid unsubstituted at the nitrogen atom. Aromatization of the oxabicycloheptene fragment of the dihaloepoxyiso-indolonecarboxylic acids gave a series of 7-carboxy-2-R-isoindol-1-ones. © 2012 Springer Science+Business Media, Inc

Trigger low-voltage devices electromechanical apparatus

Based on the analysis of the existing classification of low-voltage electromechanical devices, it was proposed, on the basis of the functions performed, to unite into the group of electromagnetic mechanisms the indicating relays, vacuum contactors, time relays with clockwork, and executive bodies of circuit breaker releases. The definition of launching devices is given, the main feature of which is a mechanical characteristic, the change of which, with appropriate coordination with the traction characteristic of an electromagnet, can lead to an improvement of the most important characteristics of these devices, such as power consumption and resistance to mechanical influencing factors. On the example of the calculation of the index relay, it is shown and experimentally confirmed that a change in the initial force of the mechanical characteristic and its rigidity leads to a decrease in power consumption while maintaining shock stability

Analysis of small intermediate relays from leading manufacturers

This paper presents a comparative analysis of technical characteristics and designs of small intermediate relays from various manufacturers. The following main characteristics of relay are considered: operation and release values; weight and dimensions; power consumption; time parameters; reliability characteristics. The design of the relays of the Russian and international manufacturers are being discussed, their design features that affect the technical characteristics are considered. It is noted that the fastening of movable contacts directly to the armature (relays from Finder, Relpol, Irkutsk Relay Plant) requires a flexible connection with the relay contacts, which leads to more complicated assembly and calibration of relays. It is shown that the kinematic diagram in the presence of free travel with no mechanical coupling with the contact pusher, used in the relay from Schrack, can reduce power consumption and increase the vibration and shock resistance of the relay break contacts. In Schrack AC relays, the operating clearance zone is configured to create a short-circuited loop with reduced electrical resistance and to provide optimum conditions for reducing armature vibration. The appropriate relay designs in terms of improving technical characteristics are proposed. The advantage of a flat return spring over cylindrical coil springs in terms of manufacturing technology and stability of mechanical characteristics of relay is shown. It was revealed that the electromagnetic drive of the Schrack relay compares favorably with electromagnetic drives of other companies in terms of the use of stray magnetic fluxes to create a useful electromagnetic torque. Based on the results of the comparative analysis and experimental study of existing relay designs, recommendations were formulated for the development of a new series of the Russian small intermediate relays within the framework of the import substitution program