scholarly journals INFLUENCE OF COEFFICIENT VARIATION ON THE VALUE OPTIMAL LEVEL OF MAINTENANCE

2021 ◽  
pp. 16-20
Author(s):  
I.V. Tolok ◽  
G.V. Banzak ◽  
E.S. Lenkov ◽  
T.V. Bondarenko
Keyword(s):  
Operating Time ◽  
Modern Society ◽  
Optimal Level ◽  
Technical Condition ◽  
General Idea ◽  
Time To Failure ◽  
Coefficient Variation ◽  
Failure State ◽  
Wear And Tear ◽  
The Cost

Complex technical objects in modern society are extremely important. Such objects belong to the class of recoverable objects of long-term repeated use. They tend to be expensive and costly to operate. To ensure the required level of reliability during their operation, maintenance is usually carried out, the essence of which is the timely preventive replacement of elements that are in a pre-failure state. A characteristic feature of complex technical objects for special purposes is the presence in their composition of a large number (tens, hundreds of thousands) of different types of component parts that have different levels of reliability, different patterns of their wear and tear processes. This feature requires a more subtle approach to the organization and planning of maintenance during their operation. The problem is that during the development of such facilities, all issues related to maintainability and maintenance should be addressed already at the early stages of facility design. If you do not provide in advance the necessary hardware and software for the built-in monitoring of technical condition (TC) of the object, do not develop and “build” the maintenance technology into the object, then it will not be possible to realize in the future a possible gain in the reliability of object due to maintenance. Since all these issues must be resolved at the stage of object creation (when the object does not yet exist), mathematical models of the maintenance process are needed, with the help of which it would be possible to calculate the possible gain in the level of reliability of facility due to maintenance, to estimate the cost costs required for this. Then, based on such calculations, make a decision on the need for maintenance for this type of objects and, if such a decision is made, develop structure of the maintenance system, choose the most acceptable maintenance strategy, and determine its optimal parameters. In this paper, we study the influence of the coefficient variation on value of the optimal level of maintenance. The work also confirms the general idea that the smaller value of the coefficient variation of random operating time to failure of the serviced elements, greater optimal value of maintenance level should be.

scholarly journals COMPARATIVE STUDY OF DIFFERENT MAINTENANCE STRATEGIES

2020 ◽  
pp. 14-22
Author(s):  
I.V. Tolok ◽  
G.V. Banzak ◽  
E.S. Lenkov ◽  
L.M. Vozikova
Keyword(s):  
Technical Condition ◽  
Cost Structure ◽  
Maintenance Strategy ◽  
Optimal Parameters ◽  
Maintenance Strategies ◽  
Reliability Indicators ◽  
Wear And Tear ◽  
Optimal Maintenance ◽  
The Cost ◽  
Maintenance Process

A characteristic feature of complex technical objects for special purposes is the presence in their composition of a large number (tens, hundreds of thousands) of various types component parts, which have different levels of reliability, different patterns of their wear and tear processes. This feature requires a more subtle approach to the organization and planning of maintenance in course of their operation. The problem is that in the development of such facilities, all issues related to maintainability and maintenance should be addressed already at the early stages of facility design. If you do not provide in advance the necessary hardware and software for the built-in monitoring of technical condition (TC) of the object, do not develop and "build" the maintenance technology into the object, then it will not be possible to realize in the future a possible gain in the reliability of the object due to maintenance. Since all these issues must be resolved at the stage of object creation (when the object does not yet exist), mathematical models of the maintenance process are needed, with the help of which it would be possible to calculate the possible gain in the level of reliability the facility due to maintenance, to estimate the cost costs required for this. Then, on the basis of such calculations, make a decision on the need for maintenance for this type of objects and, if such a decision is made, develop the structure of the maintenance system, choose the most acceptable maintenance strategy, and determine its optimal parameters. The article shows that the optimal parameters of various maintenance strategies significantly depend on both the reliability and cost structure of the facility and specified requirements for the facility's reliability . The higher the specified value , the more serviced items should be included in the optimal maintenance strategy. It has also been proven that the effectiveness of various maintenance strategies depends significantly on the reliability and cost structure of object. If the distribution of cost restored (including serviced) elements is closely correlated with the distribution of their reliability indicators, difference in effectiveness of different maintenance strategies is reduced. This is clearly seen in the example of Test-2 object, for which the least reliable elements are also the most expensive.

scholarly journals JUSTIFICATION OPTIMAL PARAMETERS OF REGULATED MAINTENANCE STRATEGY

2020 ◽  
pp. 13-22
Author(s):  
S.V. Lienkov ◽  
I.V. Tolok ◽  
G.V. Banzak ◽  
R.Yu. Koltsov ◽  
E.S. Lenkov ◽  
...  
Keyword(s):  
Technical Condition ◽  
Complex Model ◽  
Maintenance Strategy ◽  
Optimal Parameters ◽  
Maintenance System ◽  
Different Types ◽  
Wear And Tear ◽  
The Cost ◽  
Maintenance Process ◽  
Different Levels

A characteristic feature of complex technical objects for special purposes is the presence in their composition of a large number (tens, hundreds of thousands) of different types component parts that have different levels of reliability, different patterns of their wear and tear processes. This feature requires a more subtle approach to the organization and planning maintenance in the course of their operation. The problem is that in the development of such facilities, all issues related to maintainability and maintenance should be addressed already at the early stages of facility design. If you do not provide in advance the necessary hardware and software for the built-in monitoring of the technical condition (TC) of the facility, do not develop and “build” the maintenance technology into facility, then it will not be possible to realize in the future a possible gain in the reliability of the facility due to maintenance. Since all these issues must be resolved at the stage of object creation (when object does not yet exist), mathematical models of the maintenance process are needed, with the help of which it would be possible to calculate the possible gain in the level of reliability facility due to maintenance, estimate the cost costs required for this. Then, based on such calculations, make a decision on the need for maintenance given type of objects and, if such a decision is made, develop the structure of the maintenance system, choose the most acceptable maintenance strategy, and determine its optimal parameters. The paper shows that the model for the regulated maintenance strategy is an improved version of the already known models and is introduced into the complex model for the purpose of comparative assessment of various maintenance strategies. In addition, it should be borne in mind that in practice, some cases, a regulated maintenance strategy may be preferable to MCC strategies.

Contribution to Rolling Bearing Reliability Modeling

2011 ◽  
Vol 110-116 ◽  
pp. 2497-2503 ◽  
Author(s):  
Zdenek Vintr ◽  
Michal Vintr
Keyword(s):  
Operating Time ◽  
Rolling Bearing ◽  
Time To Failure ◽  
Rolling Bearings ◽  
Mean Time To Failure ◽  
Reliability Modeling ◽  
Time Between Failures ◽  
Large Groups ◽  
Mean Time

Rolling bearings are usually considered to be non-repaired items the reliability of which is characterized by mean time to failure, or so called basic rating life. Reliability describes these parameters well in case the bearings are used in operation up to the very time the failure occurs, or during the time corresponding with basic rating life. In case of railway applications the bearings are often used in large groups and are preventively replaced after much shorter operating time as compared with their basic rating life. In the article there is a model which enables us to describe the bearings reliability in this specific case and to specify a number of failures which might be expected from a group of bearings during operating time, or to determine mean operating time between failures of bearings.

THE TECHNICAL CONDITION OF THE SURVEYED HYDRAULIC UNITS IN THE MOSCOW REGION AND THE CLASSIFICATION FEATURES OF THEIR RESERVOIRS

2021 ◽  
pp. 69-79
Author(s):  
V. V. GRITSAN ◽  
Keyword(s):  
Technical Condition ◽  
Moscow Region ◽  
Risk Level ◽  
Ecological Framework ◽  
Safety Level ◽  
Repair Work ◽  
Hydraulic Unit ◽  
Technical Parameters ◽  
Characteristic Features ◽  
The Cost

The article presents the results of surveys of 311 class IV hydraulic structures carried out in 2016-2020 in the Moscow region. All the reservoirs of the surveyed hydraulic units were classified according to their characteristic features, the technical condition of culverts and dams was assessed, there was established the safety level of both separate structures and hydraulic units as a whole. During the surveys, the technical parameters of the surveyed structures were established, the state of each structure and the hydraulic unit as a whole was assessed, a possibility of their accident and a risk level for the downstream areas were considered. At the same time, recommendations were developed for the elimination of serious damage and, with the help of an examination, the amount of the cost of the necessary repair work was determined. The paper also assesses the issues of the ecological state of the areas where the hydraulic units are located and the hydraulic units themselves as blocks of the ecological framework of the territories.

scholarly journals RESEARCH OF QUALITY FORMATION OF TRANSPORT SERVICES BY PASSENGER TRANSPORT ENTERPRISES OF EU

2021 ◽  
Vol 49 (2) ◽  
pp. 122-130
Author(s):  
Nazarenko I ◽  
Keyword(s):  
Quality Criteria ◽  
Modern Society ◽  
Enterprise Management ◽  
Passenger Transport ◽  
Global Trends ◽  
Transport Services ◽  
Object Of Study ◽  
The Cost ◽  
Transport Complex

The article examines the processes, criteria and factors to ensure the quality of passenger transport services. Object of study - processes to ensure the quality of passenger transport services in the context of European integration of Ukraine. Purpose - a study of the world experience in the formation of the concept of quality of transport services, summarizing the main factors that affect the quality of transport services, as well as the main criteria affecting the qualitative characteristics of the services of the transport. Method study - generalization of fundamental works of Ukrainian and foreign scientists of economists is in the internal checking system, dialectical going, fundamental positions of economic theory, system-logical approach near research of the economic phenomena and processes. Satisfaction the needs of society and economy of passenger transport services depends on the quality and timeliness of those services. Questions of quality passenger transport services are interested in users of transport services, companies providing them. However, the requirements and the basic criteria for assessing the quality they are different. If the passenger transport enterprise interested in providing their services with minimal effort and money, the service users in their assessment pay attention not only on the cost of services, but also on transport safety, comfort, delivery time, etc.. The quality of the transport concept of integrated services, which is constantly being developed and improved. Global trends show that the quality of transport services must ensure the needs and expectations of consumers. Accordingly, it is increasing the importance of defining the qualities that affect the quality of service. Given the transient and dynamic nature of modern society and the lifestyle of the main consumers of the services the system factors and quality criteria must be flexible and dynamic to meet the industry's competitiveness on the European market of services. Awareness of the main criteria for assessing the quality of services will help to identify potential strengths and weaknesses. This will help improve not only the quality but also the process of enterprise management, industry, improve customer satisfaction of services received, will increase competitiveness. The results of the article can be inculcated in-process services of enterprises of a transport complex. KEYWORDS: QUALITY, TRANSPORT SERVICE. CRITERIA of QUALITY, TRANSPORT.

scholarly journals ESTIMATION OF VEHICLE OPERATING TIME TAKING INTO ACCOUNT THE INFLUENCE OF A NUMBER OF FACTORS

2021 ◽  
Vol 1 (37) ◽  
pp. 76-85
Author(s):  
A. Krasheninin
Keyword(s):  
Service Life ◽  
Operating Time ◽  
Material Resources ◽  
Number Of Factors ◽  
Additional Costs ◽  
Definition Of ◽  
Optimal Average ◽  
The Cost ◽  
The Impact ◽  
Standard Service

Modern vehicles operated on the railways of Ukraine have almost exhausted or exceeded their resource. The overuse of financial and material resources for their maintenance continues. The standard service life of vehicles was calculated on stable economic conditions of use of vehicles and their timely updating in process of aging. The service life of modern vehicles is determined by the influence of many factors, the disregard of which can lead to significant costs, even in compliance with the standard service life. For railway transport, these factors need modern clarification, as in operation their service life often exceeds the standard or, as for intermodal transport, the service life does not have a strict justification. Accordingly, the article analyzes the issues of assessing the impact on the service life of vehicles of the components of the cost of its maintenance and average daily mileage. It is shown that, firstly, the definition of the service life of vehicles must be linked to the cost of vehicle development, its creation, testing and production, the cost of operation and storage, as well as additional costs, and secondly , with the optimal average daily mileage, at which all the costs are minimal.

scholarly journals Thyroidectomy under Local Anaesthesia; Experience from a Tertiary Hospital in Kumasi, Ghana

2020 ◽  
Vol 2 (2) ◽  
pp. 01-07
Author(s):  
Anna Konney ◽  
Mawutor Dzogbefia ◽  
Philip Oppong Peprah ◽  
Derrick Gyimah ◽  
Isaac Barnor
Keyword(s):  
General Anaesthesia ◽  
Local Anaesthesia ◽  
Operating Time ◽  
Cost Effective ◽  
Tertiary Hospital ◽  
Tertiary Referral Hospital ◽  
Thyroid Lobectomy ◽  
Cervical Plexus Block ◽  
Plexus Block ◽  
The Cost

Objectives: Improvement in anaesthesia has allowed thyroidectomies to be performed mainly under general anaesthesia. There is however a growing interest in performing thyroid surgery under local or regional anaesthesia. The objective of this study was to analyse and share our experience with safety of thyroidectomy under regional cervical plexus block/ local anaesthesia in a tertiary referral hospital in Ghana. Materials and Methods: A retrospective study was conducted on all patients who had thyroidectomy under local anaesthesia from 1st January 2017 to 31st May 2018 in KATH. Data collected were demography, grade of goitre, operating time, and duration of hospital stay, complications and cost effectiveness of the procedure. Data was analysed using Stata version 16.0software. Results: A total of 105 thyroidectomies were done in the study period out of which 16 were done under local anaesthesia. All 16 patients (16 females, 100%) and majority 11 (68.75%) were aged between 30 and 50 years. 11 (68.75) had grade IB goitres. The most frequently performed surgery was thyroid lobectomy 12 (75%) and in 75% of cases the surgery was completed between 60 and 90 minutes. Most patients, 9 (56.25%) were discharged home within 48 hours following surgery. The cost of treatment was averagely 30% less compared to same surgery under general anaesthesia. No complications were recorded in the post-operative period. Conclusions: Comprehensive clinical assessment and careful patient selection for thyroidectomy under local anaesthesia result in good surgical outcomes. The procedure is safe and cost-effective and should be performed by experienced surgeons for the best outcomes.

scholarly journals Criminal law measures of ensuring the security of the crypto sphere

2019 ◽  
Vol 3 (1) ◽  
pp. 155-162
Author(s):  
Oleg Stepanov ◽  
Denis Pechegin
Keyword(s):  
Criminal Law ◽  
Foreign Currency ◽  
Modern Society ◽  
Developed Countries ◽  
Legal Regulation ◽  
Financial Asset ◽  
Financial Instruments ◽  
The Us ◽  
Draft Bill ◽  
The Cost

In the first issue of the Bratislava Law Review magazine for 2018, our article addressed the problem of legal regulation of relations related to the crypto sphere “Failure to repatiate funds in foreign currency from abroad and modern issues of currency regulation” was published. In December 2017, Bitcoin predicted the cost of $ 40 – $ 100 thousand. However, in 2018, the situation changed-the Bitcoin exchange rate began to lose from $ 0.5 to $ 1 thousand per day, and its market capitalization fell to $ 70 billion. The crisis of the crypto market has affected not only the capitalization of cryptocurrencies, but also the issues of legal regulation of relations associated with its use. Currently, only three countries – Sweden, the Netherlands and Japan – recognize cryptocurrency as a legal means of payment. In Spain, the cryptocurrency is classified as an electronic means of payment only in relation to the gaming business. The legislation of Germany, as well as Finland, allows to classify cryptocurrencies as financial instruments. In China, Singapore and Norway cryptocurrency is considered as a financial asset in the US – as property, i.e. developed countries are in no hurry to equate cryptocurrency to means of payment. In Russia, the use of cryptocurrencies is not regulated by any rules, but there is no legislation prohibiting the circulation of cryptocurrencies as means of payment. At the same time, the draft bill “On digital nancial assets”, designed to regulate financial relations in the crypto sphere, completely excludes the issues of mining and circulation of existing crypto-currencies. However, new electronic entities carry certain risks associated with their turnover. In this regard, many States seek to develop mechanisms to ensure the security of actions in the new crypto sphere of legal relations before the direct legalization of cryptocurrencies and other modern electronic entities. The purpose of the article is to analyze the approaches related to the security of the crypto sphere in modern society by criminal law measures taking into account foreign experience.

scholarly journals Organization of the Process of Productive Operation of Equipment as One of the Necessary Conditions of Rational Production Organization

2020 ◽  
Vol 9 (3) ◽  
pp. 3589-3593
Keyword(s):  
Labour Productivity ◽  
Unit Cost ◽  
Operating Time ◽  
Production Capacity ◽  
Working Hours ◽  
Technical Condition ◽  
Necessary Condition ◽  
Equipment Maintenance ◽  
Organization Of Production ◽  
Production Organization

The service and equipment repairing process is the necessary condition for the growth of production capacity of enterprises, and thereafter it predetermines the approach for organization of production and upbuilding of production streams. In the article different options of reduction of working hours loss are considered, due to equipment downtime elimination because of repair and equipment maintenance on the reason of the increased operation. Also, in the article reserves of growth of labour productivity and reductions of unit cost are identified. It is proved, that current equipment monitoring allows to eliminate different defects in rationing of operating time of the equipment, it also allows to reach the permanent production’s rhythms, to increase the monitoring level, to provide the timeliness delivery of materials and components. As the example, in the research was used factual material of planned measurement of technical condition of the equipment on a separate production of GAS Group, methods of monitoring of technical condition and productive equipment maintenance and standard criteria of the equipment’s condition were developed.

scholarly journals Assessment of the technical condition of lift guides using a magnetic field

2021 ◽  
Vol 2130 (1) ◽  
pp. 012003
Author(s):  
P Lonkwic ◽  
T Krakowski ◽  
H Ruta
Keyword(s):  
Early Stage ◽  
Technical Condition ◽  
Operating Conditions ◽  
Measuring Head ◽  
Cross Sectional ◽  
Correct Operation ◽  
Emergency Braking ◽  
Wear And Tear ◽  
Equipment Failures ◽  
Novel Concept

Abstract The systems that monitor individual components of machines and devices are under constant development. The ability to detect damages at an early stage allows failures to be prevented, so any uncontrolled downtime can be predicted in a controlled manner. Continuous monitoring of technical condition is an activity that also helps to reduce the losses due to equipment failures. However, not all areas can be monitored continuously. Such areas include lift guides where wear and tear can occur naturally, i.e. through abrasion of the material layer due to interaction with moving guide shoes or after emergency braking. Emergency braking causes local damages to the guide through plastic deformation of its surface resulting from indentation of the knurled roller of the brake. Such places are cleaned mechanically, which results in local reduction of the cross-sectional area. In such a case, it is difficult to continuously assess the technical condition of guides due to the prevailing operating conditions. Therefore, a concept of a head enabling assessment of the technical condition of guides at every stage of their operation has been developed. This article presents the novel concept of a magnetic head used for assessing the technical condition of lift guide rails that are the running track of lifting equipment. The initial tests were performed on the original test setup. The concept of the developed measuring head was verified for correct operation on specially prepared flat bars with holes. The results obtained in the form of laboratory tests proved that the proposed measuring head concept can be applied to the measurements under real conditions.

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