Maintenance Technicians Research Articles

Digital Assistance in the Maintenance of Offshore Wind Parks

Harsh environmental conditions, time pressure due to tightly calculated maintenance windows, complex technical systems and high quality standards determine the working environment for the maintenance and repair of offshore wind farms. Despite good qualifications and diverse training courses, maintenance technicians are reliant on information from manuals and checklists when performing their tasks and must document their work results in protocols. Both the supply of information and the data acquisition show a multitude of media disruptions. Hence, the processes on site and in the postprocessing are carried out slowly and uncertainly. The assistance system presented is intended to contribute to a consistently digital information flow and to support the technicians in a task-specific manner. Augmented Reality (AR) offers a way of presenting information and interacting with the assistance system during work execution. Using the example of the maintenance of crane systems used in a variety of ways in offshore wind farms, this article shows which potential can be tapped through digital assistance systems and AR applications.

Havacılık Sektöründe Zaman Baskısının Teknostrese Etkisi: Uçak Bakım Teknisyenleri Üzerine Bir Araştırma (The Effect of Time Pressure on Technostress in Aviation Industry: Research on Aircraft Maintenance Technicians)

Purpose – The purpose of this study is to examine the effect of time pressure on technostress in aviation industry and whether the time pressure and technostress perception of aircraft maintenance technicians differ according to demographic characteristics. Design/methodology/approach – The sampling of the study consists of 177 aircraft and helicopter maintenance technicians working in the public sector in Malatya province. Questionnaire method was used to collect data in the study. The data obtained from the questionnaire were subjected to scale validity and reliability, confirmatory factor analysis, correlation, simple linear regression, T-test and ANOVA analysis in SPSS 21 and AMOS 24 package programs. Findings – According to the research results, it was seen that time pressure positively affects the technostress in the aviation industry. It was observed that the perception of time pressure of maintenance technicians according to the age group and education level, and the perception of technostress according to the working time and education level differ. However, according to the marital status and job title, it was observed that there is no significant difference in maintenance technicians' time pressure and technostress perception. Discussion – In this study carried out in the aviation industry, it was determined that time pressure and technostress are positively related and time pressure is a determinant of the change in the perception of technostress of maintenance technicians. According to demographic characteristics, technicians' time pressure and technostress perception differ. It is possible to say that time pressure and technostress can cause errors caused by the human factor in the aircraft maintenance industry. The study is thought to make a contribution to the literature related to the aviation, aircraft maintenance and flight safety.

An Assessment of Aircraft Maintenance Technician Competency

Aircraft maintenance activities are one of the most important criteria for the safe and effective execution of aviation operations., In aircraft accidents and incidents, maintenance factor is vital for the development of safety for organizations, authorities, and countries in the aviation field. Effective maintenance activities will also contribute to the costs of organizations by ensuring the safe operations of aircraft with people. Maintenance activities are carried out by maintenance technicians in areas such as hangars or aprons. Aircraft maintenance technicians' performance in performing maintenance activities directly impacts flight safety and technician safety, which in turn has a positive or negative impact on organizations. Improving technician competency assessment processes can reduce maintenance errors, improve technician performance, create positive impacts on safe and efficient flight operations, reduce maintenance costs and benefit of the entire aviation industry. Technician competency should be considered in performance evaluations and assignments by assessing at all levels with the compatibility of widely used human resources management methods. In this study, technician competency assessment processes are mentioned, the effects of these processes on aviation safety are explained and solutions are proposed to develop and apply the assessment processes.

Análisis del nivel de fatiga a Técnicos de mantenimiento en aviación militar

El propósito de este estudio a través de una investigación cuantitativa, transversal utilizando una prueba de Yoshitake, fue identificar los niveles de síntoma de fatiga y su respuestas de tipo emocional, cognitivo y conductual que puede tener y afectar al técnico de mantenimiento en militar aviación, profesional capaz de cumplir actividades de mantenimiento de aviones y régimen militar, los cuales de una población de estudio de 40 personas el 66% de las mismas presentan síntomas de fatiga entre moderada a excesiva, que tendría incidencia a los niveles de calidad óptimos en el cumplimiento de procesos de mantenimiento en aviación y a la seguridad operacional de aviación.

Application Design of Optical Network Defect Tracking based on Location-Based Service

To maintain good service quality, network maintenance is needed. Device maintenance must be carried out as quickly and accurately if supported by an application device that can find the right location as fast as possible. Maintenance devises related to defective optical network cables, optical distribution point (ODP) panel, and ODC (Optical Distribution Cabinet) panel, to FTM (Fiber Termination Management) room. Through the three existing locations, maintenance technicians often difficulties to find the exact location of the ODC and to find out the status of the ports that are in the ODC. By utilizing features on mobile devices. LBS communicates from two-way interactions and can combine three technologies: Geographic Information System, Internet Service, and Mobile Device

THE VALUE OF ABANDONMENT: THE GIACOMINI PARK IN ITALY

​An abandoned disposal site for Municipal Solid Waste (Environmental Facility for Separate Collection - EFSC) located in a town of approx.10.000 inhabitants provided an opportunity for requalification of an open space and regeneration of a neglected woodland with restricted use, in accordance with EEC Regulations 2052/88. Both these elements were deemed strategic for different reasons. A juxtaposition of “natural”/artificial both requiring intervention. Two critical elements, two issues subject to ongoing debate by public administrations striving to identify an equilibrium in an attempt to proactively support this type of area. An open space, of value in its own right due to uninterrupted availability, multifunctional and readily organizable but burdened by a need for control and management, and the vegetation and its importance as an environmental vector, a symbol of strategic needs encumbered by maintenance and governance issues. An obsolete area conveys a double value: it both contains and constitutes the neglected object, two separate conditions featuring an active subject in the first case and in the second the object of the action itself. The “non-use” may be referred either to a container and/or to the context of space, terrain vagues or volume. The term “to abandon” is linked to a negative concept corresponding to synonyms such as to give up or desist from doing something, to leave definitively  forever implying a surrendering of control and responsibility, terms and concepts indicating varying degrees of awareness, time frames and modalities. Each is associated with an indisputable innate and deep-rooted hostility towards an interpretative vision according to which mankind is the ordinator architect of all things mundane, a maintenance technician and supervisor aware of all that goes on before his eyes. On losing control (by choice or necessity) and thus leaving something behind, this position however assumes a lesser role, being somehow ill-suited to cover an active role in a routine setting.

TEFL PROFESSORS' E-LEARNING EXPERIENCES DURING THE COVID 19 PANDEMIC

<p>This study aimed at revealing teaching English as a foreign language (TEFL) professors' eLearning experiences during the Covid 19 pandemic in the Gaza Strip higher education institutions. For this end, the researcher designed a (20) open-ended questions questionnaires to be completed by (32) TEFL professors in (8) Palestinian higher education institutions. Results showed that TEFL professors need training to develop their skills in designing, developing and drawing action plan for TEFL e-courses that achieve the objectives of foreign language teaching\ learning. Palestinian TEFL professors spent (4- 7) hours daily preparing, meeting, guiding, helping and facilitating learning by using different eLearning programs and network social media such as Moodle, Google classroom, Zoom, WhatsApp and Facebook. They adopted different teaching methods as well as different types of evaluation and following up in order to measure the objectives achievement; however, they neglected developing thinking and real life skills. The most challenges for both TEFL professors and learners were insufficient knowledge about eLearning and technical problems. TEFL professors action plan was focused on reducing the number of activities and drawing clear procedures with all the needed tools and activities for each objective in the course. Based on the findings, the researcher recommends that higher education institutions should provide training courses in the field of eLearning for both learners and professors, prepare a guide for designing and developing e-courses and provide professional technicians for maintenance of equipment and should regularly fix various technical malfunctions.</p><p> </p><p><strong> Article visualizations:</strong></p><p><img src="/-counters-/edu_01/0656/a.php" alt="Hit counter" /></p>

NON-VIBRATIONAL FAULT ANALYSIS OF TURBOJET ENGINE BEARINGS BY USING DEEP NEURAL NETWORKS

This paper depicts the implementation of deep neural networks in predicting common faults of the turbojet engine bearings by training the model with images and processing them by designing proper Deep Neural Network model apart from conventional vibration analysis methods, for faster detection of bearing health and reusability. The turbojet engines have higher main-shaft speeds operating at elevated temperature conditions, reducing the bearing estimated life and thus the need of schedule maintenance. This system can identify some of the bearing damages like cracks, dents, fatigue, fretting and smearing conditions prevailing due to thermal effects, high axial and radial loads over the main-shaft, propeller shank and auxiliary systems bearings. It finally assists the aircraft maintenance engineers and technicians to reach to the conclusions of bearing conditions by taking pictures of bearings from any device and fetching them to the system for better results of bearing conditions.

Sensors for Self-Diagnosis of Electrochemical Treatment Technologies

Electrochemical oxidation appears to be a practical technology for decentralized treatment of wastewater in regions where sewer-based wastewater treatment is too expensive or otherwise impossible to construct and maintain.1 As of now, the control processes used by many systems rely principally on successive events that are time dependent and come with little level of monitoring but little feedback into the system process.2-3 One reason is the high cost of sensors and automation systems used in industrial installations cannot easily translate into household or public bathroom products for developing countries where capital expenditure is limited.Additionally, failures associated with onsite treatment technology have to be addressed otherwise the health and the environment of the users in direct contact would suffer. In the technology developed by Hoffmann et al. 3 , most repairs are simple, requiring only a screwdriver, yet without interactive instructions, local electricians and plumbers have been unable to get units properly serviced. From ethnography research, we also found the potential for service interruption is something we must eliminate for true user adoption of our sanitation solution.As an answer to this challenge, we integrated a suite of inexpensive sensors (e.g. ORP, color, turbidity, voltage, current, water level, leakage) in and around the electrochemical treatment system (picture attached) and to a local computer (Raspberry Pi + Arduino) that can diagnose failure modes and send alerts to on-demand repair technicians and users4. Our M2M, IoT technology uses a proprietary mobile application to deliver straight-forward, pictorial instructions that guide maintenance technicians regardless of literacy level.In this study we present the results from the field testing of the system “at scale” in two identical prototypes using electrochemical disinfection and treatment of toilet wastewater. The results from this study enable a refinement in the choice of sensors and the algorithms used to diagnose electrochemical water treatment quality and prevent system failures.

The Development of Service Desk Application (SDA) as a Media to Improve Care Services and Asset Improvement in the University

An asset is a wealth. Assets at universities in the form of facilities and infrastructure are used as learning media. To ensure the assets are in good condition, assets must be managed properly. Universities is an entity that has various types of assets and distributed in various work units. Maintenance technicians have the task of carrying out maintenance and repair of assets. Care and repair history must be recorded. Requests for repairing damaged assets or having problems must be dealt with quickly. However, some universities are still implementing conventional systems. The purpose of this study is to develop Service Desk Application (SDA) as medium to improve maintenance and repair services for campus assets quickly and precisely. SDA is a centralized service application that is used to handle repair requests from customers. The results showed that SDA can monitor the status and progress of asset maintenance and control the performance of technicians so that they can complete work quickly and according to procedures, SDA serves as a useful knowledge-based management to enrich knowledge so that if there are problems with similar assets, then the solution to the problem can be immediately known.

Post-job Data Analysis by Python for a Miniature Recorder in Drilling Motors

A vibration recorder has been deployed to capture the dynamics data of drilling motors for their operation and health evaluation. The recorder is usually inserted inside the rotor catcher of a conventional drilling motor in such a way that no extra length is introduced to the planned bottom hole assembly (BHA). The recorder can log data over the full operation cycle of a drilling motor, including vibration during surface activities and downhole operation. A post-job data analyzer was specifically designed based on Python. The analyzer processes the recorded data and generates statistics, time plots, and the various statistical plots such as histograms. These statistics and plots help the operators and maintenance technicians to gain insights into the motor operation and performance. The analyzer can provide adequate information on a drilling motor to asset owners for maintenance and operation optimization without analysis training or qualification from operators.

Development of a tool for access worktime estimation in aircraft maintenance

This study was aimed to find a way how to deal with hardly predictable circumstances while performing routine access works during aircraft heavy maintenance and to estimate the time spent with the work. The lack of maintenance data was crucial in dealing with this issue, therefore, additional measurements were necessary. For this purpose, this study was done in cooperation with Czech Airlines Technics Maintenance Repair Organization. The company currently estimates timing of panel manipulation based on the information contained in the manufacturer’s documentation. A database was established with work measurements of maintenance technicians accessing panels during real aircraft maintenance. They should by their nature reflect complications arising during the access panel manipulation and of the specific operational factors in the company. The main importance of the database lies in the creation of additional data to refine the aircraft maintenance planning estimates. Based on the measurements, it was possible to demonstrate that the access panel manipulation times as stated in the manufacturer’s documentation are only indicative. For each measurement performed, the measured overall time of panel manipulation was much higher than the equivalent time estimates by the manufacturer. During the measurements, several other factors were also discovered as causal to differences in the manipulation times. The database served as the basis for a developed software tool providing more accurate estimates of access panel manipulation times and resulting in more accurate estimates in maintenance planning in the Czech Airlines Technics, although the results are well reusable with other Maintenance Repair Organizations.

INVESTIGATION OF THE EFFECT OF COMPETENCY ASSESSMENT PROCESSES ON AIRCRAFT MAINTENANCE TECHNICIAN

ABSTRACT Aircraft maintenance activities are one of the most important criteria for the safe and effective execution of aviation operations. In aircraft accidents and incidents, maintenance factor is vital for the development of safety for organizations, authorities and countries in the aviation field. Effective maintenance activities will also contribute to the costs of organizations by ensuring the safe operations of aircraft with people. Maintenance activities are carried out by maintenance technicians in areas such as hangars or aprons. Aircraft maintenance technicians' performance in performing maintenance activities directly impacts flight safety and technician safety, which in turn has a positive or negative impact on organizations. Improving technician competency assessment processes can reduce maintenance errors, improve technician performance, create positive impacts on safe and efficient flight operations, reduce maintenance costs and benefit of entire aviation industry. Technician competency should be considered in performance evaluations and assignments by assessing in all levels with the compatibility of videly used human resources management methods. In this study, technician competence assessment processes are mentioned, the effects of these processes on aviation safety are explained and solutions are proposed to develop and apply the assessment processes. Keywords: Aircraft maintenance, aircraft maintenance technician competency, competency assessment, human factors in aviation.

An integrated approach of SWARA and fuzzy COPRAS for maintenance technicians’ selection factors ranking

In spite of proliferation of maintenance work-force research, the maintenance community has deficient insight into the technicians’ selection process. Building on studies focusing on technical crew selection and uncertainties, this paper offers a framework to potentially remedy this lack. First, the establishment of a fuzzy-rooted structure and connection of it with step-wise weight assessment ratio analysis (SWARA) and complex proportional assessment of alternatives (COPRAS) can enlarge the research community’s comprehension of the competent selection process and could be initiated and completed by selection teams for maintenance technicians. Second, the put forward structure confronts the widespread description of where to obtain technicians, directing attention from the steps-to-selection to mere sources of obtaining technicians. Thus, this paper establishes the manner, in a particular context that the integration of fuzzy-SWARA and COPRAS could add to the research community’s perception of tackling uncertainties all around the maintenance technicians, while building on ideas from the human resource management literature as well as the technical engineering literature.

Bayesian network method for fault diagnosis of civil aircraft environment control system

This paper addresses the issues of fault diagnosis of the environmental control system of a certain commercial aircraft model of which the environmental control system has a high failure rate in field and causes many unplanned maintenance events. Because of the complexity and reciprocal compensation mechanism of the environmental control system, it is difficult to carry out fault isolation timely once the failure occurred during aircraft turnaround time, which thus may cause flight delay or even cancelation. The original contribution of this work is to propose a Bayesian network–based fault diagnosis method for commercial aircraft environmental control system where a multi-information fusion mechanism is used to incorporate the system first principle, expert experience and condition monitoring data. It incorporates extraction technology of sensor feature parameters and the structural learning of Bayesian network to realize the effective diagnosis of multiple faults. A case study is conducted based on a data set from a commercial aircraft fleet. The results show that the fault isolation ratio of this method is greater than 89%. The proposed Bayesian fault diagnosis network method can be used as a troubleshooting tool for airline maintenance technicians in fault isolation of environmental control system, reducing the time spent on-line troubleshooting and aircraft downtime.

Nestor: A Tool for Natural Language Annotation of Short Texts

Nestor is a software tool that annotates natural language CSV (comma-separated variable) files, with a UTF-8 (Unicode Transformation Format – 8-bit) encoding, using a process called tagging [1]. The objective of Nestor is to help analysts make their natural language data, which is often unstructured, filled with technical content, jargon, mispellings, and abbreviations, computable to improve analysis. An example of natural language data that could be input to Nestor and the subsequent output data and the corresponding output is shown in Table 1. The annotated datasets generated by Nestor (as either a CSV or .h5 file) can be used for different analysis techniques, such as failure prediction, problem hot spot identification, and maintenance technician expertise assessment, as shown in [2–10]. Currently, the majority of use cases involve maintenance in the engineering domain (manufacturing, mining, heating ventilation and air conditioning (HVAC)), however, any natural language CSV file with UTF-8 encoding can be input to Nestor.

Judgemental errors in aviation maintenance

Aircraft maintenance is a critical success factor in the aviation sector, and incorrect maintenance actions themselves can be the cause of accidents. Judgemental errors are the top causal factors of maintenance-related aviation accidents. This study asks why judgemental errors occur in maintenance. Referring to six aviation accidents, we show how various biases contributed to those accidents. We first filtered aviation accident reports, looking for accidents linked to errors in maintenance judgements. We analysed the investigation reports, as well as the relevant interview transcriptions. Then we set the characteristics of the actions behind the accidents within the context of the literature and the taxonomy of reasons for judgemental biases. Our results demonstrate how various biases, such as theory-induced blindness, optimistic bias, and substitution bias misled maintenance technicians and eventually become the main cause of a catastrophe. We also find these biases are interrelated, with one causing another to develop. We discuss how these judgemental errors could relate to loss of situation awareness, and suggest interventions to mitigate them.

Occurrence of faults in water installations of residential buildings: An analysis based on user complaints

Fault analysis in building installations enables design optimisation and reduction of errors in future projects. This paper's objective is to catalogue, quantify and analyse faults in residential buildings' water installations, based on user complaints and the ‘learning from failures’ philosophy. To this end, 436 complaints related to plumbing and sewage installations of 318 Spanish residential buildings were analysed. The results show that ‘buried-sewage-pipes’ lead to most of problems (43.8%), followed by ‘exposed-sewage-pipes’ (38.3%) and ‘plumbing’ (17.9%). The most recurring faults were ‘leakages and humidities’ (52.98%) and ‘anomalies and mismatches’ (33.25%). As for the causes leading to said faults, the most significant one was ‘damage in the installation’ (29.31%). The type of construction in which most cases occurred was ‘apartment blocks’ (52%), followed by ‘attached houses’ (29%). These results contribute to the reduction of errors in the design and construction stages of residential buildings and are useful for drafters, designers and builders, as well as for building users and maintenance technicians.

Age replacement policy in the case of no data: the effect of Weibull parameter estimation

Age replacement is a common maintenance policy when wear-out failures occur, and it is characterised by periodic replacement of components. Data on time to failure (TTF), often modelled with the Weibull function, are necessary for estimating optimal replacement intervals to minimise the total maintenance costs. In many cases, such as new components, new machines or new installations, no TTF data are available, so the Weibull parameters and optimal replacement interval cannot be estimated. To overcome this problem, these parameters can be assessed from the experience of the maintenance engineers and technicians. The aim of this study is investigating the relationship between the error in parameter estimation and additional maintenance costs related to this error. Analysis of variance (ANOVA) and multifactorial analysis are carried out for investigating the influence of these estimations on the final costs. Economic decision maps are introduced for supporting maintenance engineering in defining the maintenance policy with minimal additional cost in the case of no data being available. The analysis shows that, when no data are available, the application of the age replacement policy can result in a global saving of more than 50% compared with corrective maintenance.

Organizational and interorganizational factors affecting safety in the Chinese civil aviation industry

I aimed to identify organizational and interorganizational factors that affect flight safety, and to determine possible differences in organizational factors according to differences in organizational performance. I interviewed 28 pilots, 33 air traffic controllers, and 17 maintenance technicians, and used content analysis by coding to analyze the data. Results showed that (a) cluster analysis revealed 3 relevant organizational factors: information interface, technical management, and nontechnical management, with employees mostly concerned about the third factor; (b) pilots expected to be served by controllers, whereas controllers would like to be in control of their relationship with pilots; and (c) compared with maintenance technicians, pilots were particularly concerned with safety. Implications for safety research and management in the Chinese civil aviation industry are discussed.