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The present work is devoted to the analysis of the most important reliability indicators of components of electrical devices of mining dump trucks, and analytical methods of their evaluation are proposed. A mathematical model for calculating the reliability of electrical devices integrated into the electrical systems of quarry dump trucks is presented. The model takes into account various loads arising in the process of operation and their influence on reliability reduction. Optimisation of maintenance and repair schedules of electrical equipment has revealed problems for research. One of them is the classification of electrical equipment by similar residual life, which allows the formation of effective repair and maintenance cycles. The analysis of statistical data on damages revealed the regularities of their occurrence, which is an important factor in assessing the reliability of electrical equipment in mining production. For quantitative assessment of reliability, it is proposed to use the parameter of the average expected operating time per failure. This parameter characterises the relative reliability of electrical equipment and is a determining factor of its reliability. The developed mathematical model of equipment failures with differentiation of maintained equipment by repeated service life allows flexible schedules of maintenance and repair to be created. The realisation of such cycles makes it possible to move from planned repairs to the system of repair according to the actual resource of the equipment. [ABSTRACT FROM AUTHOR]

The rapid growth of technology worldwide in different ways drives the construction sector to take the same path. Smart cities, Digital Twins, Building Information Modeling (BIM), and the Internet of Things (IoT) are the trends in this way today. Also, integrating Building Information Modeling (BIM) and Internet of Things (IoT) technologies has revolutionized how buildings are designed, constructed, maintained, and managed. On the other hand, the complexity, high cost, need for expertise, and other things make the maintenance process and facility management by human inspections, commercial software, and different tools not suitable for the growth of the technology. This paper presents a proposal for a workflow of integration between BIM, and an algorithm of Maintenance System with IoT and highlights its potential to enhance building performance and facility management. The paper explores this innovative system's underlying principles, benefits, challenges, and implementation strategies. Furthermore, it discusses the implications of BIM, and the proposed algorithm of Maintenance System with IoT integration on various stakeholders, including building owners, facility managers, and occupants by using a case study. The findings collected by a questionnaire for some experts emphasize the importance of adopting this integrated approach to optimize building operations, improve maintenance practices, and create sustainable and intelligent built environments. [ABSTRACT FROM AUTHOR]

The paper introduces the concept of a transducer base for HUMS of the suspension system of a high mobility wheeled vehicle. The basic principles of the maintenance system with HUMS as a subsystem and its structure are clarified. The main benefits for operators of the maintenance system after implementation of HUMS into vehicles are presented. Preliminary ranges of loads to be monitored, generated in a selected point in the suspension system of a vehicle with a GVW of 3.5T class are presented, as well as general dimensions and material selection for the base of the transducer. [ABSTRACT FROM AUTHOR]

Aiming to investigate the problem that dam-monitoring data are difficult to analyze in a timely and accurate automated manner, in this paper, we propose an automated framework for dam health monitoring based on data microservices. The framework consists of structural components, monitoring sensors, and a digital virtual model, which is a hybrid of a finite element (FE) model, a geometric model, a mathematical model, and a deep learning algorithm. Long short-term memory (LSTM) was employed to accurately fit and predict the monitoring data, while dynamic inversion and simulation were used to calibrate and update the data in the hybrid model. The automated tool enables systematic maintenance and management, minimizing errors that are commonly associated with manual visual inspections of structures. The effectiveness of the framework was successfully validated in the safety monitoring and management of a practical dam project, in which the hybrid model improved the prediction accuracy of monitored data, with a maximum absolute error of 0.35 mm. The proposed method can be considered user-friendly and cost-effective, which improves the operational and maintenance efficiency of the project with practical significance. [ABSTRACT FROM AUTHOR]

Ensuring the best performance of a Windows Server system is critical for businesses since any operational failures may result in significant financial losses. Considering this, the use of automated mistake resolution solutions appears as a proactive technique for dealing with prospective concerns. This study provides a ground-breaking technique specialized for Windows Server settings, consisting of three essential pieces deliberately intended to identify and control faults. A thorough examination of the first factor, Predictive Errors, necessitates a thorough examination of server performance data. By studying this data, the system may proactively detect locations where problems may occur. This foresight allows the system to take preventive steps, eventually reducing downtime and improving overall server performance. The second component, the Automated Error Resolution module, uses scripts and automated procedures to correct mistakes that occur. Notably, this module allows for the inclusion of human operators in the resolution process when necessary, guaranteeing a balanced and successful approach. Configuration Management is critical in preserving the server environment's accuracy. It manages the tracking of configuration changes using a combination of automated and human-driven mechanisms. This comprehensive approach results in an integrated solution that adeptly prioritizes the correction of misconfigured services based on their possible influence on the overall performance of the system. Acknowledgment The research activities are divided into three stages. The first phase is a thorough Literature Review to obtain insights and knowledge from current sources. This informs the succeeding System Design and Implementation phase, in which a prototype of the desired system is created. This prototype is subjected to a thorough review that considers issues such as accuracy and scalability. The prototype is exposed to real-world testing situations in the last phase, Evaluation and Validation, to fine-tune its functionality and improve its performance. The consequences of this research are considerable, with the potential to greatly improve the reliability of Windows Server settings. This research offers itself as a disruptive method with far-reaching advantages for organizations by reducing downtime, improving performance, and implementing cost-effective strategies. [ABSTRACT FROM AUTHOR]

Purpose. Modern methodologies for maintaining technical facilities are focused on simultaneously ensuring a given level of equipment reliability and minimizing system maintenance costs. The development of maintenance systems is usually based on the use of equipment reliability data, analysis of diagnostic results and forecasting of the residual life of locomotive equipment. In addition, the development of maintenance systems takes into account the costs of maintenance and repair of components. The main goal of the study is to increase the efficiency of the locomotive fleet by reducing the cost of maintaining locomotives, taking into account the technical condition of its components. Methodology. To achieve this goal, we propose a methodology for determining the rational periods for diagnosing locomotive components based on minimizing the cost of diagnostics and performing maintenance and repair of equipment. To determine the frequency of control, we used data on the reliability of components and parts obtained from the processing of statistical information on the operation of locomotives in operation, as well as data on the costs of restoring components in the event of failures. Findings. A method for determining the rational periods for diagnosing locomotive components based on minimizing the cost of diagnosing and restoring them in case of failure is proposed. Based on the analysis of the reliability of hydraulic transmissions of locomotives in their operation, the reliability indicators of hydraulic transmission units and parts are determined in the form of dependencies of the average number of hydraulic transmission failures on the operating time of the locomotive. A techno-economic map of hydraulic transmission repair and a techno-economic map of its diagnostics have been developed. The results of determining the frequency of diagnostics of the hydraulic transmission UGP750–1200PR of diesel locomotives TGM4 and TGM6 are presented. Originality. The methodology for determining the frequency of monitoring the technical condition of locomotive components has been further developed by taking into account the impact of the system of preventive, scheduled maintenance and diagnostics on the reliability of the locomotive. Practical value. The use of the proposed methodology for the formation of a system for repairing and diagnosing locomotives and their components will allow the formation of a system for maintaining locomotives taking into account their actual condition.

Since 2017, China Railway Group has vigorously promoted the reform of EMU maintenance system, continuously extended the EMU maintenance cycle, optimized the maintenance contents and projects, improved the maintenance quality and efficiency and reduced the maintenance cost. Firstly, this paper discusses the maintenance management system of EMU, combs the effectiveness of the reform of maintenance system, puts forward the direction of reform and development, and studies the impact of the reform on the calculation of maintenance workload of EMU base (depot). Combined with relevant planning and passenger transport development, the allocation of EMUs in the planning period is predicted, the scale and capacity adaptability of the whole railway EMU base (depot) are deeply analyzed, and the maintenance capacity development plan is put forward accordingly. Combined with the influence of the reform on the maintenance production, the influence on the equipment configuration of EMU base (depot) is analyzed. This paper innovatively studies the impact of the reform of maintenance system on the calculation of maintenance capacity, analyzes the development plan of the maintenance capacity of the national railway system, and innovatively puts forward the impact on facilities and equipment configuration. The relevant research results have strong reference significance for the construction of EMU base (depot). [ABSTRACT FROM AUTHOR]

Introduction: Unit risk management is a critical component of gas refining management, as risks that are not well-managed may lead to trip production failures. The present study aimed to provide a structural model for investigating the role and effect of different variables on stopping the gas production process in the gas refinery. Material and Methods: This study was a retrospective cross-sectional and systematic analysis, which was carried out on key risks in the trip gas sweetening unit in a gas refinery industry located in Asaluyeh, Iran. The systems analysis was applied by using Fishbone Diagram, and then data modeling was prepared by Structural Equation Modeling (SEM) for an incident that occurred during gas sweetening production. Tools for the data analysis included the SPSS 24 and Smart PLS 2 software. Results: Results of this research indicate that “Environment Risk” with a path coefficient of 0.943 and T- Value of 103.791; “Cost Risk” with a path coefficient of 0.937 and T- Value of 95.168; “Implementation of management system Risk” with a path coefficient of 0.847 and T- Value of 35.23; “Accident Risk” with path coefficient of 0.577 and T- Value of 25.410; “Time Risk” with path coefficient of 0.758 and T- Value of 15.121; “Human Error Risk” with path coefficient of 0.712 and T- Value of 11.215 had the most important coefficients of the paths respectively, that are effective in stopping production concerning other risks. Also, by comparing the path coefficients of the risks we can see that the impact of each of the risks on stopping production is different. Conclusion: The findings of the present study revealed that a combination of variables can affect stopping production in the gas industry. Therefore, the role of these risks in losses in the refinery system should be investigated.

Paper aims: The Industry 4.0 movement highlights the importance of information and communication technologies and the two main reasons for this are advances in digitalization and automation. However, organizations trying to implement technologies face several barriers in their systems. These barriers are intensified in legacy systems, tightly coupled to organizational processes. Thus, to overcome these barriers, an adequacy strategy was structured, and detailed in the context of interoperability. Originality: This article proposes a digital transformation framework focused on interoperability in maintenance systems. Research method: Aiming to make legacy systems work together with cyber-physical systems, the proposed framework suggests its suitability based on strategic decisions, using Multicriteria Decision Making (MCDM) methods. Main findings: The framework outputs demonstrate that people are the main drivers of digital transformation and that the strategies proposed by it are coherent with the actual development of both cases, proven in a new interview one year apart from its application. Implications for theory and practice: Real industrial cases demonstrate that the framework can guarantee interoperability while facilitating strategic decisions to implement technologies in legacy maintenance systems. In the end, the legacy system, which will interoperate with the new technologies, is called Smart Legacy System. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Animal Production & Processing Technology / JurnalIlmu Produksi dan Teknologi Hasil Peternakan is the property of IPB University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming to investigate the problem that dam-monitoring data are difficult to analyze in a timely and accurate automated manner, in this paper, we propose an automated framework for dam health monitoring based on data microservices. The framework consists of structural components, monitoring sensors, and a digital virtual model, which is a hybrid of a finite element (FE) model, a geometric model, a mathematical model, and a deep learning algorithm. Long short-term memory (LSTM) was employed to accurately fit and predict the monitoring data, while dynamic inversion and simulation were used to calibrate and update the data in the hybrid model. The automated tool enables systematic maintenance and management, minimizing errors that are commonly associated with manual visual inspections of structures. The effectiveness of the framework was successfully validated in the safety monitoring and management of a practical dam project, in which the hybrid model improved the prediction accuracy of monitored data, with a maximum absolute error of 0.35 mm. The proposed method can be considered user-friendly and cost-effective, which improves the operational and maintenance efficiency of the project with practical significance.

Simulation models have become promising methods to investigate and improve real-world systems. This paper describes the development of effective simulation-based models for maintenance systems in a manufacturing environment whereby production lines send their faulty but repairable items to a repair shop. The proposed models aim at investigating the centralized storage of repaired items with three replenishing strategies, lot-for-lot (L4L), economic order quantity and reorder point (Q-R), and minimum-maximum order level (s-S) reordering policies of repairable items with backordering allowance in a risk-free and flexible manner to effectively manage the procurement of new repairable items and control three inventories of repairable items, repaired ready-for-use, new, and faulty awaiting repair. The models take into account the uncertain environment of maintenance systems and the probabilistic nature of the failures, repair times, and lead times of repairable items. The demand for repairable items in these three inventories is both stochastic and dynamic. A simulation case problem is presented to demonstrate the suitability and applicability of the proposed simulation models and to study the influence of different parameters on performance measures using parametric analysis. The main results are the vital decision-making insights provided by the developed models about the three reordering policies and the three inventories of repairable items. These managerial insights are essential for achieving minimum inventory costs and maximum service levels. [ABSTRACT FROM AUTHOR]

The maintenance system is a key system that provides continuity and safety of the operation of production systems and that affects the safety of people working in these systems. At the same time, the maintenance system is a set of work processes carried out by people under specific environmental conditions, using specific equipment and within a specific organizational and management structure. The purpose of this article is to identify the main management factors that affect occupational safety and to rank these factors in terms of their effectiveness in ensuring safe maintenance, using the grey systems theory. Based on the literature analysis, 12 key management factors were identified and then subjected to expert assessment. In order to rank the factors, a decision model based on the grey systems theory (GST), i.e. systems with incomplete and uncertain information about structure and behavior, was developed and verified. The use of GST in the area of ensuring safety in maintenance is original. The findings of the article will be very useful for managers in implementing safe maintenance systems in various sectors of the economy.

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the article by means of the theory of time reservation the reasonableness of use of planned downtime of engineering equipment for preventive maintenance and current repair in order to maintain its reliability at the required level is substantiated. To quantify the impact of the process of organizing the functioning of the maintenance system in accordance with the proposed model to change the level of reliability of engineering technology developed a method of calculating the coefficient of technical use of engineering machines, which takes into account not idealized, but the real possibilities for the use of daily downtime of the equipment as a reserve time its technical use.

The article deals with materials of service military clothing in the Czech Armed Forces (CAF) and their possible innovations. Useful properties were identified based on the results of a questionnaire survey in the field of satisfaction of soldiers with current military uniform. Properties as colourfastness, abrasion and pilling of materials became the subject of measurement experiment. The measurement took place in the Laboratory of Physiological Comfort of the Technical University of Liberec. The aim of the work was to create design possibilities for improving the application properties of materials. The results are a source of important information for the stage of design and innovation in the introduction of new service military uniform, leading to improved military equipment. [ABSTRACT FROM AUTHOR]

Proper operation of railway vehicles is the basis for the functioning of a safe railway system. At the same time, it is not possible to talk about the safe use of a vehicle without adequately carried out maintenance processes. Due to legislative changes in August 2017, the maintenance system of railway vehicles has changed significantly. In most cases, it is the entities responsible for maintenance that are fully liable for the shape of the maintenance documentation, not the national security authority (in Poland the President of the Rail Transport Office) as has been the case so far. That is a big challenge for everyone involved in maintaining railway vehicles. The article presents the system of maintenance of railway vehicles as critical for the railway system safety, with the division into those registered in the National Railway Register and the unregistered ones. National and EU requirements for maintenance systems as well as the conditions for the implementation of “changes” in these systems have been presented, based, among others, on the results of the risk assessment of the threats they generate.

Abstract The world today is the world of organizations and human resources are considered as a competitive advantage among organizations. To this end, keeping this important source is the responsibility of each organization. Therefore, the purpose of this study was to investigate the drivers of human resource support in Birjand University of Medical Sciences and also to investigate the impact of each of these drivers on the maintenance of manpower is at the university. This study is a descriptive-survey based on the applied purpose. The statistical population of this study included employees of Birjand University of Medical Sciences. Among them, 143 people were selected using sample sampling as sample members. The data gathering tool was two researcher-made questionnaires. Validity of the questionnaires were confirmed by content validity and their reliabilites were calculated using Cronbach's alpha of 0.98 and 0.95. Data analysis was performed using SPSS 23 and Smart PLS 3 software using structural equation modeling, single-variable t-test, and Friedman test. The results showed that organizational, environmental and individual factors affect the maintenance of manpower in Birjand University of Medical Sciences. Among the 18 factors of manpower maintenance, management style and leadership ranked first and as the most important factor and environmental opportunities in the last rank and it is considered to be the least important factor in maintaining human resources in the university. Introduction The world today is a world of organizations and human resources are considered to be the most important sources of the organization. Even with the advancement of organizations and their transformation into a bunch of hardware, the role of man as a vital and strategic factor in the survival of the organization is still evident (Shafie & Engashte, 2017). For this reason, in a competitive situation and in an environment where successive changes and innovation are its main features, only organizations that have succeeded in acquiring a grasp of the strategic role of their human resources and having skilled human resources, knowledge Centered, and capable (Tahmasebi et al., 2012). In this regard, the key role of the manpower has been created; HR managers in each organization systematically design processes for maintaining these forces and, with a great attitude, examine the arrival and departure of people, the consequences and costs of losing staff, and for this reason, manpower maintenance will be more important than hiring. In other words, even if the recruiting, selection, appointment and improvement operations are to be done in a desirable manner without paying attention to the maintenance, the results of the management's actions will not be significant (Eskandari and Abedi, 2009). Currently, higher education institutions, especially universities, play a major role in the social, economic, cultural, and political development of each country. Considering the intensive competition of these institutions in different fields and the existence of problems in maintaining human resources in this area, attention to the issue of keeping in universities is necessary. Nevertheless, few studies have been carried out in this regard and somehow the problem of keeping employees in the higher education system of the country, especially medical universities, has been neglected. For this purpose, the purpose of this research is to investigate the proponents of manpower maintenance in Birjand University of Medical Sciences. Case study The statistical population of the study consisted of all the staff of Birjand University of Medical Sciences in 230 people. Based on Cochran's formula, 143 people were selected through a sampling method. Materials and Methods The present study is a descriptive-survey method in terms of purpose, applied, and method. The main instrument for collecting information was two researcher-made questionnaires distributed amongst sample members. In order to evaluate the validity of the questionnaires and the dimensions of the questionnaires, several selected experts were selected from the faculty members of the university, and proposed reforms were carried out by them. To assess the reliability of the questionnaires, a prototype including 30 pre-test questionnaires was used. The reliability coefficient was calculated using the Cronbach's alpha for the whole questionnaires of 0.98 and 0.95. This reliability indicates the reliability of the research tools. For analyzing the obtained data, descriptive statistics (mean and percentage of frequency) and inferential statistics (structural equation modeling, single variable t test, and Friedman test) were used with SPSS 23 and Smart PLS 3 software. Discussion and Results The main Hypothesis 1. Organizational drivers of Human Resource Management in Birjand University of Medical Sciences have a significant effect. 2. Individual drivers of Human Resource Management in Birjand University of Medical Sciences have a significant effect. 3. Environmental drivers of Human Resource Management in Birjand University of Medical Sciences have a significant effect. According to the analyzing of the data, since the value of T for all three variables is greater than 1/96, it can be claimed that organizational, individual and environmental factors have a significant relationship with the maintenance of the workforce. Also, based on the one-sample t-test, since the level of assurance for all factors was less than 0.05, it can be claimed that the health and safety factors, benefits and services, the system of compensation services, employee socialization, improvement of the job path, job satisfaction organizational commitment, management style and leadership, providing realistic information, performance evaluation system and control, organizational justice, organizational culture, organizational climate, organizational structure, organizational support, learning and growth, occupational characteristics and, finally, environmental opportunities in medical university Birjand city has a favorable situation. Finally, based on Friedman's test, leadership and leadership styles are in the first place and ranked as the most important factor in maintaining manpower at Birjand University of Medical Sciences and environmental opportunities. Conclusion The purpose of this research is to investigate the drivers of human resource preservation in Birjand University of Medical Sciences. For this purpose, the research hypotheses were developed and tested by using the structural equation modeling method. The results of the research hypothesis showed that organizational, individual and environmental factors affect the maintenance of manpower in Birjand University of Medical Sciences. Also, based on the results of single-variable t test, it was determined that the factors of manpower maintenance in the studied population are desirable. Also, according to Friedman rank test results, among the factors of manpower maintenance in Birjand University of Medical Sciences, management style and leadership ranked first, organizational climate and organizational culture were ranked second and third, respectively. The most favorable the situation was among the other factors of the manpower maintenance of this university.

Purpose. Improving the efficiency of the use of locomotives by choosing a rational maintenance system that takes into account the assessment of the effect of dependent failures on the cost of their life cycle is the main purpose of this paper. Methodology. The relevance of introducing LCC (Life Cycle Cost) approaches in locomotive facilities is explained by the introduction of new locomotives with on-board control and diagnostic systems, as well as the development of the theory of traction rolling stock maintenance systems. The cost of a locomotive as a traction unit ceases to be the determining factor. This is because the locomotive maintenance and repair cost for the entire period of its operation is much higher than the initial cost of the locomotive. The paper analyses the existing approaches to managing the cost of the life cycle of locomotives at the stages of selecting, updating, upgrading and operating the traction rolling stock. The necessity of improving the methods for assessing the degree of influence of reliability indicators of locomotive assemblies on the choice of the maintenance system and the cost of the locomotive life cycle is substantiated. Findings. It is proposed to use the concept of «the effect of dependent failures» when calculating the cost of locomotive renewal after unscheduled repairs and its life cycle cost. We improved the methods for determining the cost of unscheduled repairs, taking into account dependent failures and the coefficient of assessment of the effect of dependent node failure on the locomotive maintenance system. The proposed coefficient will determine the nodes, the failure of which affects the renewal cost more than their nominal value. It will also help to take into account the probable losses due to node failure during the development and adjustment of the locomotive maintenance system. Originality. For the first time, it is proposed to use the concept of the effect of dependent failures to calculate the locomotive renewal cost when performing unscheduled repairs, as well as the locomotive life cycle cost. Practical value. The improved calculation method for determining the cost of unplanned repairs with account taken of dependent failures can be used to compare and evaluate different variants of the locomotive maintenance system and to develop the locomotive diagnostic systems.

With the rapid development of science and technology, the complexity of national defense equipment is increasing. It is difficult to complete the security task reasonably and effectively by the military security capability. Therefore, this article gives an overview of commercial aircraft maintenance system, and provides recommendations for defense equipment support based on experience accumulated during commercial aircraft maintenance system construction from civil-military integration point of view. The relevant technologies of civil aircraft maintenance system, i.e., the requirement analysis, health monitoring and management technology, maintenance strategy, support mode, and so on, are integrated into the field of defense equipment investigation, which are applied to perfect the technology and support mode of defense equipment.

Driver assistance systems are at the peak of their development and are already actively used by the world’s leading automakers as an effective tool to improve traffic safety (reducing accident rates). The driver fatigue monitoring systems at the methodological level and functional purpose are actively developing and have outlined a trend, including the transition of a number of functions from the category of assistant systems to the category of active safety systems operating in automatic mode. The most effective method of automatically interpreting the driver’s functional state in terms of driver fatigue (deep relaxation, when the number of driver errors significantly increases which can lead to an accident, the driver’s functional state preceding the fall asleep) is the most effective, having the least probability of a dangerous failure. It is based on monitoring and analysis of parameters of the electrodermal activity. Methods of automatic interpretation of the functional state of the driver allow us to expand the functionality of a number of security systems and increase their effectiveness. It shows the relevance of monitoring the driver’s functional state before the vehicles achieve full autonomy of traffic.

At the present time, for the maintenance by condition system the problems of the radioelectronic equipment technical state parameter justifying and grouping are solved, as well as solved the problems of the maintenance periods, the level of training and the number of maintenance personnel, the determining the technical state parameters values forecasting methods, the intervals for anticipating the product time between failures justifying, but these solutions are obtained under the condition of failure intensity stationarity. The study of failure intensity in the course of its nonstationarity has not been fully carried out. To carry out such studies, a mathematical suitability model has been created. Presented in the scientific article radio electronic equipment maintenance by condition system suitability model will make it possible to decide whether it is reasonable to use the current maintenance strategy or not, to restructure the maintenance system parameters and to make a decision about its suitability for a given failure intensity behavior.

At the present time, it is impossible to imagine manufacturing organizations without running maintenance systems. Maintenance is a system that supports the core processes. Therefore, a maintenance system is essential for manufacturing organizations in order to maintain competitiveness. As yet many studies have been done on maintenance systems but there is almost no study comprehensively examining various aspects of the system. In this study, defining the attributes of maintenance phenomenon, dimensions and components of maintenance system are clarified. By the use of meta-synthesis approach, previous studies are analyzed and maintenance phenomenon is categorized in five dimensions, 31 sub-dimensions, and 98 components. Finally, the effect of the specified components in 209 previous studies has been determined using Shannon entropy method. And, it has been shown that what factors or codes have received the most emphasis in each theme.

Copyright of Scientific Journal of the Military University of Land Forces is the property of Gen. Tadeusz Kosciuszko Military Academy of Land Forces and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper discusses one of the most important stages in the developed methodology for building a strategy of maintenance of railway vehicles, which is the RAMS analysis (Reliability, Availability, Maintainability, Safety) in the area of safety. The paper presents the application of RAMS analysis in the construction process (development or change) of the maintenance strategy on the example of a 6Dg diesel locomotive. Based on the conducted research, it was found that this analysis enables proper classification of hazards, quantification of the frequency of occurrence of hazards and the adoption of the appropriate criteria for risk assessment of the created strategy. [ABSTRACT FROM AUTHOR]

Achievement of industries in production and offering products depends on different factors like having an appropriate maintenance system. This issue should be reached through the most appropriate and practical methods. In this study, based on how the external parameters would influence the productivity of a maintenance system the researcher aims at designing a dynamic system model to analyze the productivity of a maintenance system using acquired information from a car device company by determination of the percentage of parameters and indexes and their influence on maintenance system productivity. The proposed model is simulated for a system with parameters of precise value according to fixed and variable maintenance policies which the results are represented. The results of different policies described by using computerized simulation of the prepared model on VENSIM software. The time horizon of the systems can be considered from several years to several decades. This research considered 12 weeks for analyzing the system. This time was specified by consultation with experts in the first session of modeling. In such environment a model of productivity evaluation and operation of maintenance seems required that in this research by analyzing influential factors on maintenance system productivity of a factory and by means of acquired samples, it was possible to measure the ratio of maintenance system operation condition according to the posed indexes and their influences on productivity operation. This situation shows that to the extent that positive indexes in the diagram are higher to the same extent maintenance system productivity of company increases. [ABSTRACT FROM AUTHOR]