The Cause of Mechanical Vibration of Palasher Synchronous Motors and its Removal

Jiří Pavelka; Josef Šimek; Pavel Kobrle; Petr Kokeš

doi:10.14311/tee.2019.4.068

The Cause of Mechanical Vibration of Palasher Synchronous Motors and its Removal

Transactions on Electrical Engineering ◽

10.14311/tee.2019.4.068 ◽

2020 ◽

Vol 8 (4) ◽

pp. 68-73

Author(s):

Jiří Pavelka ◽

Josef Šimek ◽

Pavel Kobrle ◽

Petr Kokeš

Keyword(s):

Magnetic Flux ◽

Mechanical Vibration ◽

Variable Component ◽

Font Size ◽

Mechanical Vibrations ◽

Synchronous Motors ◽

Stator Windings ◽

Before And After ◽

Direct Compensation ◽

The Russian Federation

<span style="font-family: 'Times New Roman',serif; font-size: 10pt; -ms-layout-grid-mode: line; mso-fareast-font-family: 'MS Mincho'; mso-ansi-language: EN-GB; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-GB">The paper describes the procedure and the result of the analysis of mechanical vibrations of mining machines at the Palasher mine in the Russian Federation. The cause of these vibrations was the change in the magnitude of the magnetic flux in the air gap. The simulations showed the possibility of eliminating these changes in magnetic flux by injecting suitable voltages into the stator windings. The implementation of this injection is further described by torque variable component feed-direct compensation. Finally, oscillography records are presented before and after injection.

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ПЕРСПЕКТИВЫ УЛУЧШЕНИЯ СПЕЦИАЛИЗИРОВАННОЙ ПОМОЩИ ПАЦИЕНТАМ С НЕСПЕЦИФИЧЕСКИМИ ГНОЙНЫМИ ЗАБОЛЕВАНИЯМИ ПОЗВОНОЧНИКА

Innova ◽

10.21626/innova/2020.3/03 ◽

2020 ◽

Vol 20 (3) ◽

pp. 18-24

Author(s):

Максим Юрьевич Гончаров ◽

◽

Яна Алексеевна Горева ◽

Keyword(s):

Systemic Inflammatory Response Syndrome ◽

Early Diagnosis ◽

Inflammatory Response ◽

Treatment Outcomes ◽

Improve Treatment ◽

Organizational Issues ◽

Number Of Patients ◽

Before And After ◽

Specialized Care ◽

The Russian Federation

The problem of early diagnosis of non-specific purulent diseases of the spine remains relevant. The main organizational problems in providing medical care to these patients are considered to be late diagnosis, late administration of antibacterial therapy and neurosurgical care. The goal of our work was to improve treatment outcomes by reducing the time of diagnosis and the duration of the stage before providing specialized care. Based on the identified variable factors that influenced the treatment outcomes, we proposed an algorithm for the diagnosis and treatment of non-specific purulent diseases of the spine, implemented in the activities of hospitals in the Sverdlovsk region. To evaluate the effectiveness of our proposed algorithm, we retrospectively compared the main indicators and results of the treatment of patients conducted before and after the implementation of the developed algorithm. Educational and methodological work with doctors was also important for reducing the time of diagnosis of the disease. After the implementation of the developed algorithm of diagnostics and tactics in nonspecific suppurative diseases of the spine and the necessary organizational issues, there was a reduction of the duration from the first signs of the disease to provide specialized assistance, as well as the number of patients who had gross neurological deficit and/or systemic inflammatory response syndrome upon admission to a hospital. The results obtained allow us to recommend the developed algorithm of diagnostics and tactics for non-specific purulent diseases of the spine for implementation in other regions of the Russian Federation.

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Krakatau caldera deposits: revisited and verification by geophysical means

Annals of Geophysics ◽

10.4401/ag-6404 ◽

2014 ◽

Vol 57 (5) ◽

Author(s):

Izumi Yokoyama

Keyword(s):

Wave Attenuation ◽

Gravity Anomalies ◽

Spatial Distributions ◽

Low Density ◽

Subsurface Structure ◽

Font Size ◽

S Wave ◽

Before And After ◽

Quantitative Examination ◽

Krakatau Volcano

One of the differences between volcanic craters and calderas is that the latter bottoms are flatways filled with caldera deposit with lower density in comparison to country rocks. The 1883 Krakatau eruption affords us important knowledge on caldera formation even if it was not observed with modern sophisticated instruments. First, volcanic activities of the Krakatau Islands before and after the 1883 eruption are reexamined: previous suppositions involving a caldera-forming eruption of the proto-Krakatau prior to 1883 proved to be unsupported by the bathymetric topographies and gravity anomalies on and around the Krakatau Islands. Then, Anak Krakatau is interpreted as a parasitic cone of the main Krakatau volcano. As supplementary knowledge to discussion of caldera deposits, the results of drillings at several calderas in Japan and Mexico are introduced. Mass deficiency of the caldera deposit at Krakatau caldera is estimated by the gravity anomaly observed there and converted to probable volume with suitable density. For quantitative examination of the subsurface structure beneath the Krakatau complex, spatial distributions of seismic S-wave attenuation and Vp/Vs ratios have been already studied by temporary seismological observations and their results have been published. The high ratios of Vp/Vs observed approximately at Krakatau caldera may be attributable to the caldera deposit that is low density and contain much water. As additional remarks, a zone having both the characters, S-wave attenuation and zones of relatively high Vp/Vs ratio, may be a probable magma reservoir centering at a depth of about 10 km.

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Economic consequences of mandatory price re-registration for medicines from the high-cost nosology program

Kachestvennaya klinicheskaya praktika ◽

10.37489/2588-0519-2020-3-27-33 ◽

2020 ◽

pp. 27-33

Author(s):

A. V. Rudakova ◽

D. T. Ugrekhelidze ◽

V. A. Krylov

Keyword(s):

Russian Federation ◽

Economic Consequences ◽

Malignant Neoplasms ◽

Selling Price ◽

Pricing Policy ◽

Essential Drug List ◽

Before And After ◽

The Russian Federation ◽

The Government ◽

Reference Stock

The Government Decree, approved in December 2019, required registration certificates holders of reference drugs, included in the essential drug list (EDL), submit applications for mandatory price re-registration. Drugs included in the high-cost nosology list (high-cost list) must be included in the EDL.Objective: to assess the budget impact of price re-registration for high-cost list drugs.Material and methods. The comparing economic analysis of high-cost nosology program before and after price re-registration based on the Government Decree N 1683 (effective from 16.12.2019). 125 reference stock keeping units (SKUs), included in the high-cost list, were evaluated.Results. The analysis showed, that after re-registration the prices of 66 SKUs will remain the same. The prices of 43 reference SKUs will be reduced after setting a single maximum selling price («equalization»). Prices for 16 SKUs will be reduced due to lower registered prices in the reference countries. Considering the contracts executed in 20192020, the budget of the high-cost program is up to 74.430 billion rubles, and after re-registration it will be equal to 64.162 billion rubles, so the savings will amount 10.267 billion (13.8 %). The main drivers of re-registration prices savings are: Advagraf (1.175 billion rubles), Elizaria (2.083 billion rubles) and Revlimid (2.247 billion rubles). Separately, we analyzed the consequences ofprices re-registration in the V-thgroup ofhigh-cost list, which are provided topatients with malignant neoplasms of lymphoid, hematopoietic and related tissues. It was calculated, that in 2019 the contracts for V-th group of high-cost list were signed for 19.217 billion rubles, and after the price re-registration for the purchase of the same number of drugs 16.762 billion rubles will be spent, so the savings from the price re-registration will amount to 2.455 billion rubles (12.8 %), among which 2.247 billion rubles will be provided by price re-registration of Revlimid.Conclusions. The pricing policy implemented in the Russian Federation is aimed at increasing the availability of highly effective medical care to the population of the Russian Federation and significantly reduces the burden on the budget of the healthcare system.

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Modal Analysis and Rotor-Dynamics of an Interior Permanent Magnet Synchronous Motor: An Experimental and Theoretical Study

Applied Sciences ◽

10.3390/app10175881 ◽

2020 ◽

Vol 10 (17) ◽

pp. 5881

Author(s):

Selma Čorović ◽

Damijan Miljavec

Keyword(s):

Modal Analysis ◽

Permanent Magnet ◽

Permanent Magnets ◽

Natural Frequencies ◽

Permanent Magnet Synchronous Motor ◽

Mechanical Vibration ◽

Mechanical Vibrations ◽

Wide Range ◽

Interior Permanent Magnet ◽

Interior Permanent Magnets

This paper investigates mechanical vibrations of an interior permanent magnet (IPM) synchronous electrical motor designed for a wide range of speeds by virtue of the modal and rotordynamic theory. Mechanical vibrations of the case study IPM motor components were detected and analyzed via numerical, analytical and experimental investigation. First, a finite element-based model of the stator assembly including windings was set up and validated with experimental and analytical results. Second, the influence of the presence of the motor housing on the natural frequencies of the stator and windings was investigated by virtue of numerical modal analysis. The experimental and numerical modal analyses were further carried out on the IPM rotor configuration. The results show that the natural frequencies of the IPM rotor increase due to the presence of the magnets. Finally, detailed numerical rotordynamic analysis was performed in order to investigate the most critical speeds of the IPM rotor with bearings. Based on the obtained results, the key parameters related to mechanical vibrations response phenomena, which are important when designing electrical motors with interior permanent magnets, are provided. The main findings reported here can be used for experimental and theoretical mechanical vibration analysis of other types of rotating electrical machines.

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ON TRANSPORT SECURITY IN THE RUSSIAN FEDERATION

Alternative energy sources in the transport-technological complex problems and prospects of rational use of ◽

10.12737/14032 ◽

2015 ◽

Vol 2 (1) ◽

pp. 227-229 ◽

Cited By ~ 2

Author(s):

Попова ◽

G. Popova ◽

Степин ◽

Yu Stepin

Keyword(s):

Russian Federation ◽

Federal Law ◽

Before And After ◽

The Russian Federation ◽

Mode Of Transport ◽

Terrorist Acts

The article considers terrorist acts on all kinds in the Russian Federation, the most vulnerable mode of transport. And also the comparison of the number of terrorist acts before and after the entry into force of the Federal law "On transport security".

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An Analysis of the Galvanometer Amplifier and its Response to Alternating Electromotive Forces and Mechanical Vibrations

Australian Journal of Chemistry ◽

10.1071/ch9510560 ◽

1951 ◽

Vol 4 (4) ◽

pp. 560

Author(s):

RG Wylie ◽

AFA Harper

Keyword(s):

Frequency Response ◽

Response Curve ◽

Mechanical Vibration ◽

Frequency Response Curve ◽

Mechanical Vibrations ◽

Frequency Axis ◽

Critical Damping

A system which is representative of most practical galvanometer amplifiers is analysed and the response of the system to alternating e.m.f.'s and to mechanical vibration is determined. It is shown that the values of the circuit constants can be so chosen that the galvanometer movement is at least critically damped for all conditions of operation and that, for critical damping. the frequency response curve for the amplifier to applied alternating e.m.f.'s resembles that for the galvanometer alone but is expanded along the frequency axis by a factor which depends on the degree of feedback. Mechanical vibration with a component about the axis of the galvanometer cod produces an effect which is markedly increased by the provision of feedback.

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Dynamic Analysis of Series-Connected and Mechanically-Coupled Twin Synchronous Motor Drive

Nigerian Journal of Technological Development ◽

10.4314/njtd.v17i1.5 ◽

2020 ◽

Vol 17 (1) ◽

pp. 33-39

Author(s):

I.K. Onwuka ◽

G.C. Diyoke ◽

E.S. Obe

Keyword(s):

Reduction Gear ◽

Motor Drive ◽

Stator Winding ◽

Speed Reduction ◽

Synchronous Motors ◽

Stator Windings ◽

Three Phase ◽

On Line ◽

Winding Machine ◽

The Mathematical Model

Series-connection of the stator windings of electric motors could serve a number of purposes, including load balancing between two synchronous motors. This paper modeled and analyzed a drive system of two separate three-phase synchronous motors whose stator windings are series- connected by a unique stator winding scheme, and whose shafts are mechanically coupled to a common load shaft through a speed reduction gear driven through the pinions of the respective motors. The mathematical model is developed in detail, and the system is simulated using MATLAB/SIMULINK. It is observed that for the case of a balanced load on the respective shafts of the two motors, the dynamic behavior of the two motors are identical. It is further observed that with the particular stator winding arrangement giving rise to six-windings per motor unit, each motor is essentially a three-phase motor and may be operated direct on line (DOL). Keywords: Common load shaft; DOL; series-connected stator windings; synchronous motors, six-winding machine

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Optical Fiber Based Distributed Mechanical Vibration Sensing

10.20944/preprints202104.0514.v2 ◽

2021 ◽

Author(s):

Vít Novotný ◽

Petr Sysel ◽

Aleš Prokeš ◽

Pavel Hanák ◽

Karel Slavíček ◽

...

Keyword(s):

Optical Fiber ◽

Mechanical Vibration ◽

Single Mode ◽

Mechanical Vibrations ◽

Real Situation ◽

Optical Link ◽

Distributed Sensor ◽

Sensing System ◽

System Components ◽

Vibration Sensing

The distributed long-range sensing system using the standard telecommunication single-mode optical fiber in a function of a distributed sensor for sensing of mechanical vibrations is described. Various events generating vibrations such as walking or running person, moving cars, trains and others can be detected, localized and classified. The sensor and related sensing system components were designed and constructed and the system was tested both in the laboratory and in the real situation with 88 km telecom optical link, and the results are presented.

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PENERAPAN PRINSIP-PRINSIP MUTU DAN KEAMANAN PANGAN TEMPE DI KABUPATEN LAMPUNG BARAT

Jurnal Gizi dan Pangan ◽

10.25182/jgp.2008.3.3.244-249 ◽

2008 ◽

Vol 3 (3) ◽

pp. 244

Author(s):

Suhartono Suhartono ◽

Ahmad Sulaeman ◽

Budi Setiawan

Keyword(s):

Food Safety ◽

Food Quality ◽

Small Animal ◽

Secondary Data ◽

Food Product ◽

Raw Material ◽

Small Scale ◽

Font Size ◽

Before And After ◽

Food Quality And Safety

Food Law No. 7 1996 defined food security as a condition in which the fulfillment of food for the household is reflected by the availability of sufficient food both its quantity and quality, safe, evenly distributed and within reach; meanwhile, food quality is defined as the value determined base on the criteria of food safety, nutrition content and trade standard on food stuffs, catables and beverages. The purpose of this study was to analyze the application of food quality and safety principles in the production of food product i.e tempeh at small scale industry in West Lampung. A survey on 15 selected tempeh producers was carried out using a structured questionnaire. Primary and secondary data was collected in this study through interview and observation to the 15 tempeh producers. In the general, all producers had not fully implemented food safety and quality principles as outlined in the GMP guideline. Nevertheless, the tempeh quality produced in West Lampung organoleptically was good. Several issues need to be improved i.e. cleaning raw material (soy bean), using water from safe sources, washing soy bean before and after braising, controlling small animal included mouse, and maintenance and cleany the premises.

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Student Attitudes Towards Computers Before And After Taking An Introductory AIS Course

Journal of Business & Economics Research (JBER) ◽

10.19030/jber.v2i7.2899 ◽

2011 ◽

Vol 2 (7) ◽

Author(s):

Philip W. Morris ◽

Ronald J. Daigle

Keyword(s):

Gender Difference ◽

Student Attitudes ◽

Traditional Students ◽

Computer Attitudes ◽

Font Size ◽

Computer Experience ◽

Traditional Student ◽

Positive Attitudes ◽

Before And After ◽

Non Traditional Students

Computer attitudes are measured before students take an introductory AIS course. Attitudes are positive, regardless of gender or traditional vs. non-traditional student status. No difference is noted by gender, but non-traditional students have more positive attitudes. Prior computer experience appears to explain these findings. Attitudes are measured again at semester end. Attitudes either remain the same or slightly improve for respective subgroups studied. Little if any gender difference exists, but the gap by student status is slightly greater. Impact of findings on AIS education is discussed.

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