Maintenance Technicians Research Articles

A Comparison of Single- and Multi-parameter Wave Criteria for Accessing Wind Turbines in Strategic Maintenance and Logistics Models for Offshore Wind Farms

Different vessel types for transferring technicians for maintenance and inspection of offshore wind farms are often evaluated and compared by their limiting significant wave height for accessing the wind turbines. The limiting significant wave height is also the parameter that is often used as the access criteria in strategic decision support tools for maintenance and logistics for offshore wind farms. In practice, however, other wave parameters, such as the peak wave period and wave heading, have major influence on the accessibility to a wind turbine for a given vessel. We compare the use of single-parameter and multi-parameter wave criteria for access to wind turbines in two strategic maintenance and logistics models for offshore wind farms: one simulation model and one optimization model. Multi-parameter wave criteria in the form of limiting significant wave heights as functions of peak wave period and wave heading are obtained by numerical analysis of the vessel docking operation. Results for availability, operation and maintenance costs and the optimal vessel fleet size and mix are found using both these multi-parameter wave criteria and using a corresponding single-parameter limiting significant wave height. The comparison indicates that the use of a single limiting significant wave height can give similar results as when using more complex multi-parameter wave criteria. An important precondition is that the single limiting significant wave height is carefully chosen to represent the vessel and the wave conditions.

Maintenance process modelling with Cellular Automata and Voronoi diagram

Resource allocation problems in industrial processes have been widely studied. In this paper we present a case of maintenance technicians' allocation process simulation using cellular Automata and Voronoi diagram taking into account the spatial constraints. The aim is to extend the spectrum of constraints of the resource allocation problems and improve the previous works by carrying out the spatial dimension impact on performance optimization. To illustrate our approach some simulations are given.

The Case for In-House Laboratory Equipment Maintenance

Healthcare technology management (HTM) professionals have taken a hands-off approach to laboratory equipment maintenance. Typically, there isn't much of such equipment in the inventory, and the cost to train personnel to service can be a hurdle to making the move to in-house maintenance. Additionally, in some cases the equipment has been provided free of charge in return for a long-term contract for expendable supplies used to operate the equipment. Finally, regulatory oversight from College of American Pathologists (CAP) or other agencies can discourage in-house maintenance.However, I strongly encourage all HTM professionals to help bring laboratory maintenance back in-house. While there may be some short-term pain, the potential for long-term benefits is greater. There are three main reasons to make the move. First, we in the HTM field are losing an important technical skillset by not maintaining laboratory equipment. Second, because of this diminishing skillset, the contract cost will inevitably rise due to supply and demand and manufacturers being able to control the supply. Third, we are building walls between biomedical equipment technicians (BMETs) and laboratory technicians, and that's not healthy.In-house maintenance technicians or BMETs, have traditionally, only worked on the most basic laboratory equipment. To address this lack of experience, consider sending your in-house technicians out with the manufacturer's field service engineers (FSEs) to observe how to maintain the equipment. There may be a short-term cost in slightly decreased productivity for the BMET team, but the long-term benefit is that your in-house technicians will expand their skillsets. Additionally, they may discover that some of the equipment can be maintained in-house, reducing the contract cost for your hospital.If manufacturers continue to observe that HTM departments are reluctant to bring the laboratory maintenance in-house, the cost for contract maintenance will rise. Analysis by HTM professionals to determine the cost effectiveness of maintenance contracts will become a paperwork drill.HTM professionals need to think of options other than maintenance contracts with outside vendors. What are the total costs of the maintenance contracts for laboratory equipment? Once that is calculated, determine if it is cheaper to hire a technician to take care of the laboratory maintenance. In a medium to large hospital, I would be surprised if the savings is not there. If possible, standardize all the equipment under one manufacturer. Consider bringing in a FSE who is trained in how to service the laboratory equipment. While the FSE may not have the usual background of an associate's degree or military training, his or her experience and training by the manufacturer could lead to savings.In conclusion, I encourage you to find ways to bring laboratory maintenance in-house. Be creative, find cost-saving methods that will increase response time, and increase the knowledge base of the in-house HTM. At least consider the inclusion of laboratory maintenance as part of the overarching HTM community.

The effect of non-linear delay costs on workforce mix

This paper formulates a simple model to examine the appropriate mix of dedicated and flexible maintenance technicians (servers) required when total delay cost is a non-linear function of mean delay time. The primary decision variable is the number of flexible servers needed to minimize system-related costs. Non-linear delay costs appear to significantly increase the level of cross-training required compared with previous research using a linear cost function, which showed that a small proportion of flexible servers was sufficient. This has important implications for service system designers in regard to the amount of cross-training that might be appropriate.

Portable Fault Diagnostic System Based on Network and PDA

In order to solve the problem of field fault detection for engineering vehicle, we introduce a new networked portable fault diagnostic system based on PDA. The architecture of the system is presented. The system consists of dual-tier architecture. The first tier server is based on the related technical database of engineering vehicles, and the second tier one is the technical information database downloaded from the manufactures technical resources with PDA as the terminal for maintenance technician. The system function includes information query, user interaction, data downloading and uploading as well as network communication. The software platform is composed of Microsoft SQL Server Compact (SQL CE) database, application software on PDA and computer. Meanwhile the hardware platform is mainly composed of desktop PC or dedicated server, PDA mounted with cradle, data acquisition card as well as PCMCIA network adapter and so on. Both wireless communication and USB interface are adopted in the system. It has been used in many military units. The application demonstrates that the PDA-based networked fault diagnosis system of vehicles is beneficial to data query, fault elimination and repair capability of engineering vehicles.

Identification of the Human Factors Contributing to Maintenance Failures in a Petroleum Operation

This research aimed to identify the most frequently occurring human factors contributing to maintenance-related failures within a petroleum industry organization. Commonality between failures will assist in understanding reliability in maintenance processes, thereby preventing accidents in high-hazard domains. Methods exist for understanding the human factors contributing to accidents. Their application in a maintenance context mainly has been advanced in aviation and nuclear power. Maintenance in the petroleum industry provides a different context for investigating the role that human factors play in influencing outcomes. It is therefore worth investigating the contributing human factors to improve our understanding of both human factors in reliability and the factors specific to this domain. Detailed analyses were conducted of maintenance-related failures (N = 38) in a petroleum company using structured interviews with maintenance technicians. The interview structure was based on the Human Factor Investigation Tool (HFIT), which in turn was based on Rasmussen's model of human malfunction. A mean of 9.5 factors per incident was identified across the cases investigated.The three most frequent human factors contributing to the maintenance failures were found to be assumption (79% of cases), design and maintenance (71%), and communication (66%). HFIT proved to be a useful instrument for identifying the pattern of human factors that recurred most frequently in maintenance-related failures. The high frequency of failures attributed to assumptions and communication demonstrated the importance of problem-solving abilities and organizational communication in a domain where maintenance personnel have a high degree of autonomy and a wide geographical distribution.

Caracterización de la gestión del mantenimiento de equipo biomédico en servicios de urgencia de clínicas y hospitales de Medellín en el período 2008-2009

Maintenance management is a tool that supports Biomedical Engineering staff in the development, control and direction of maintenance programs for medical equipment. Objective: to characterize the maintenance management of biomedical equipment in emergency areas of medical institutions in the metropolitan area of Medellin during 2008-2009. Materials and methods: a survey was conducted with chiefs and maintenance technicians of eleven institutions classified at level 3, belonging to the health network of the municipality of Medellin. Results: among the medical institutions included in the present study, it was found that 80% of equipment failure was related with mishandling of the devices, and 70% of maintenance work developed during the period of study was carried out by qualified Biomedical Technicians/ Technologist. On the other hand, a weakness was observed in programs for medical equipment maintenance of the surveyed institutions, as it was found that most of them had only working PM schedules, and outdated record information of equipment regarding, maintenance, acquisition or decommissioning plans of equipment. Conclusion: the study shows the existence of weaknesses in certain areas of the maintenance, such also poor organization and management, and poor availability of original spare parts.

Exposure of aircraft maintenance technicians to organophosphates from hydraulic fluids and turbine oils: A pilot study

Hydraulic fluids and turbine oils contain organophosphates like tricresyl phosphate isomers, triphenyl phosphate and tributyl phosphate from very small up to high percentages. The aim of this pilot study was to determine if aircraft maintenance technicians are exposed to relevant amounts of organophosphates. Dialkyl and diaryl phosphate metabolites of seven organophosphates were quantified in pre- and post-shift spot urine samples of technicians (N=5) by GC-MS/MS after solid phase extraction and derivatization. Pre- and post shift values of tributyl phosphate metabolites (dibutyl phosphate (DBP): median pre-shift: 12.5 μg/L, post-shift: 23.5 μg/L) and triphenyl phosphate metabolites (diphenyl phosphate (DPP): median pre-shift: 2.9 μg/L, post-shift: 3.5 μg/L) were statistically higher than in a control group from the general population (median DBP: <0.25 μg/L, median DPP: 0.5 μg/L). No tricresyl phosphate metabolites were detected. The aircraft maintenance technicians were occupationally exposed to tributyl and triphenyl phosphate but not to tricresyl phosphate, tri-(2-chloroethyl)- and tri-(2-chloropropyl)-phosphate. Further studies are necessary to collect information on sources, routes of uptake and varying exposures during different work tasks, evaluate possible health effects and to set up appropriate protective measures.

Reduction of response time during machine breakdown: a case study in semiconductor industry

Maintenance is an important facet in manufacturing industry to ensure the equipment is constantly running at optimum condition. The aim of this paper is to improve maintenance system by reducing response time, which induces long total breakdown time. Response time can be defined as time once equipment breakdown occurs until it is fixed. It is directly influenced by human factors, as an example, the maintenance personnel that will perform the maintenance activities. This human factor issue is further investigated in terms of the time taken by operator, maintenance technician, maintenance clerk, and maintenance engineer to respond to machine breakdown during corrective maintenance cases. A new maintenance system is developed to improve the current maintenance system by minimising the human response time. The new system is developed in six phases with the use of methods such as chronology for current and improved maintenance system and value stream mapping (VSM) for comparing the response time between the two systems. The system is implemented in a semiconductor company and confirmed the importance of human factor in achieving lowest response time towards effective maintenance system.

101 プローブクライマーによるワイヤーロープ健全性評価の基礎研究

In recent years, with the barrier-free public facilities, elevator has come to be also installed station and footbridge. Shortage of maintenance technicians has become a social problem with the increase of the elevator. In addition, an inspection of the elevator and amusement machine that have been suspended by wire rope is often overlooked since it depends on the visual inspection. For such a problem, by making a self-driving probe climber, work efficiency and ensure the safety of workers, such as improving the quality of maintenance can be expected. In this study, we developed a self-driving probe climber to detect of wear and corrosion damage of the wire rope at an early stage. It also provides the results of their verification for damage detection performance of wire rope and driving performance.

항공정비 분야의 공정한 안전문화 개선방안에 관한 연구

Aviation Maintenance Technician(AMT)'s error is not directly link to deficiency which is differ to flight crew's error and it potentially maintains. Due to it usually occur as undesired aircraft state, hazards, like unreported maintenance error or near miss fortunately undetected and are not develop to accident. This could be a crucial influence of an accident occurrence. To remove these hazards, just safety culture should be support that anyone can report about safety problems and person who reported safety problems and hazards like near miss, should not get disadvantages. Also if it is satisfied, they must exempt for punishment and guaranteed for security. Hence, on this study, aviation maintenance site's just culture need to be researched and analysed about improvement for aviation maintenance field's positive just culture.

Development of Automobile Simulative Teaching System Based on the ZigBee Technology

Having fast and precise automobile fault check is a basic skill for automobile maintenance technicians. The simulation and setting of fault in automobile simulative teaching system need to be fast and accurate. The automobile simulative teaching system, based on ZigBee technology and usage of wireless sensor networks, is built to set fault for several EFI car engine training tables. It facilitates the students’ exercise and examination. The system uses the CC2430 chip to achieve the network node hardware and software design, information collection and wireless transmission. The practical application shows that the system has a simple structure, high reliability, broad application prospects.

Implementation of Autonomous Maintenance in Semiconductor Industry: A Case Study

Maintenance is a vital component in ensuring machines to run smoothly. While, maintenance technicians are responsible in conserving the conditions of machine by performing regular inspections. This study was conducted to investigate the performance of maintenance system in a company by identifying the critical machine with the highest breakdown frequency and time. It was found that high breakdown was due to the high workload of technicians, where no extra time can be allocated for thorough inspection task. Technicians do not have enough support in performing maintenance task. In this paper, Autonomous Maintenance (AM) program is suggested to reduce technicians’ workload through operators’ involvement. Technicians work is reduced with the aid of operators, which gives them more time for other maintenance tasks. The AM process flow is implemented in a case study company as a verification and validation processes.

An authorable context-aware augmented reality system to assist the maintenance technicians

The increasing complexity and the technology advancement of equipment pose challenges to the maintenance technicians nowadays. Augmented reality (AR) technology can be used to assist the maintenance technicians by providing useful information through visual interactions, e.g., superimposing the maintenance instructions virtually on the real equipment. However, to improve the usability of the state-of-the-art AR-assisted maintenance systems in routine and ad hoc maintenance activities, the virtual information provided should be adapted to the various contexts, i.e., context relevant. For example, the information provided should accord to the status of the activity and the user’s expertise level. In addition, the rendered AR contents should not be “read-only”, such that the maintenance technicians become passive information receivers. Providing the technicians with the means to interact with the AR contents actively is useful as they can rectify any incorrect AR contents that have been created by the AR developers and author AR contents to record and share the accumulated knowledge and experience on equipment maintenance with other technicians. In this paper, an authorable context-aware AR System (ACARS) is proposed to assist the maintenance technicians. To make ACARS context-aware and authorable, a bi-directional authoring tool, which enables the AR developers to create context-relevant information via a desktop 2D user interface and the maintenance technicians to author AR contents on-site, is proposed. A prototype system has been developed, and a case study has been conducted to demonstrate the usability of ACARS.

긍정적인 항공정비안전보고문화에 관한 연구

In field of Aviation Maintenance, honest and expedite voluntary report of potential hazard provide airworthiness aircraft by eliminating or avoiding from dangerous factors of aircraft. Although it supports for safety flight, voluntary incident reporting system consist of Aviation practitioner and require cooperation of practitioner due to there are no forcibleness. These occur when positive safety culture and report culture are settled. In this regard, this study firstly identify the current status of Aviation Safety Reporting System in Korea. Then, this article also find out the level of reporting culture of the AMT(Aircraft Maintenance Technicians) and problems in reporting system. Finally, suggestions on the model of positive safety reporting culture in a field of aircraft maintenance.

Why do employees take more initiatives to improve their performance after co-developing performance measures? A field study

Performance measurements may stimulate employee initiatives to improve operational performance, especially when employees themselves participate in the development of their own departmental performance measures. Using the theory of planned behavior, we examine why this occurs in a beverage manufacturing company where we helped bottling line maintenance technicians develop measures about the results of their own work. Our analyses are based on qualitative data gathered at 156 meetings, 34 semi-structured interviews, quantitative performance data from the company's information systems, and quantitative questionnaire data. We found that the participatory development process increased employees’ attitude, perceived social pressure and perceived capability to take initiative. Moreover, the departmental performance improved when the jointly developed performance measures were put to use.

Analysis of the implementation of ergonomic design at the new units of an oil refinery

Ergonomic design is the adaptation of working conditions to human limitations and skills in the physical design phase of a new installation, a new working system, or new products or tools. Based on this concept, the purpose of this work was to analyze the implementation of ergonomic design at the new industrial units of an oil refinery, using the method of Ergonomic Workplace Assessment. This study was conducted by a multidisciplinary team composed of operation, maintenance and industrial safety technicians, ergonomists, designers and engineers. The analysis involved 6 production units, 1 industrial wastewater treatment unit, and 3 utilities units, all in the design detailing phase, for which 455 ergonomic requirements were identified. An analysis and characterization of the requirements identified for 5 of the production units, involving a total of 246 items, indicated that 62% were related to difficult access and blockage operations, while 15% were related to difficulties in the circulation of employees inside the units. Based on these data, it was found that the ergonomic requirements identified in the design detailing phase of an industrial unit involve physical ergonomics, and that it is very difficult to identify requirements related to organizational or cognitive ergonomics.

The passing of the shift in aircraft maintenance - a task that produces deaths

Maintenance tasks, especially in heavy maintenance, may not be completed in a single shift. Aircraft maintenance technicians often take work in progress by colleagues, and spend the incomplete work for a change of team. The need for accuracy and efficiency of information transfer in many cases, without having time to have a meeting to pass the service is a crucial aspect of maintenance work. The ideal shift change can occur normally before delivery and continues to proceed normally after delivery. Although a shift change create challenges for communication, they also offer opportunities to detect and correct errors, where the task of delivery is an opportunity to identify the problem and fix it. In this case, the task was done correctly the first round, however, a problem began when the second round took. One example is a case in which the first round have removed a defective part for replacement and let the component of aircraft at end of turn with problems. Instead of ordering and installation of an operational component, the second round was then reinstall the faulty component, not realizing he had information about the problem attached.

Aircraft Maintenance Decision System Based on Real-time Condition Monitoring

Aiming at the problem that an aircraft has the capability of real-time condition monitoring but maintenance technicians carry out the maintenance action after equipment malfunction existing aircraft maintenance decision system based on real-time condition monitoring is designed applying PHM technology and malfunction forecast, report, maintenance action and full life health management are obtained.

The passing of the shift in aircraft maintenance - a task that produces deaths

Maintenance tasks, especially in heavy maintenance, may not be completed in a single shift. Aircraft maintenance technicians often take work in progress by colleagues, and spend the incomplete work for a change of team. The need for accuracy and efficiency of information transfer in many cases, without having time to have a meeting to pass the service is a crucial aspect of maintenance work. The ideal shift change can occur normally before delivery and continues to proceed normally after delivery. Although a shift change create challenges for communication, they also offer opportunities to detect and correct errors, where the task of delivery is an opportunity to identify the problem and fix it. In this case, the task was done correctly the first round, however, a problem began when the second round took. One example is a case in which the first round have removed a defective part for replacement and let the component of aircraft at end of turn with problems. Instead of ordering and installation of an operational component, the second round was then reinstall the faulty component, not realizing he had information about the problem attached.