Bad Maintenance Research Articles

An estimation of the tower crane safety risk factors in the Vietnamese construction industry

The construction industry is among the riskiest sectors worldwide due to its involvement in complex and hazardous activities, primarily because of the use of tower cranes. Tower cranes are considered the most hazardous construction machinery, contributing to a high rate of serious accidents, including fatalities and disabling injuries, not only in Vietnam but also globally. In this paper, we identify and evaluate 42 tower crane safety risk factors specific to the Vietnamese construction industry based on their probability of occurrence, severity of impact, and associated risk levels. The paper reveals that the most probable risk factor is “Unfavorable winds (including intensity, direction, etc.)” with a mean value of 3.641. The factor with the highest severity is “Wire rope is broken” with a mean value of 4.179. Furthermore, the study shows that twenty-five out of forty-two (59.52%) factors present a moderate risk level, with a Relative Significant Index Score (RSIS) ranging from 8.019 to 13.047. Among these, the factor “Bad maintenance management of the tower crane and auxiliary aids” poses the highest risk level, with an RSIS value of 13.047. This paper aims to enhance the understanding oftower crane safety among subcontractors, government safety regulators, main contractors, maintenance personnel, and workers in the Vietnamese construction industry. Additionally, the methodology presented in this paper can be adapted for assessing safety risk factors in other industries within Vietnam.

Steel-Concrete Composite Bridge Diagnostics and Reconstruction

Abstract Many bridges in Slovakia are reaching their designed life span these days. Due to frequent errors during the construction of those bridges as well as bad maintenance, steel-concrete bridges are now in a critical state and urgent repairs of those structures are needed. In this article progressive methods of retrofitting existing concrete bridges are shown. In the presented method, the original pillars and original bridge deck will remain in their place, and on the existing deck new composite, steel-concrete bridge deck with encased steel members of progressive shape will be created. This method brings significant cost reduction for such retrofitting and enables the application of increased loads on the bridge.

Steel‐Concrete Composite Bridge Diagnostics and Reconstruction

AbstractMany bridges in Slovakia are reaching their designed life span these days. Due to frequent errors during the construction of those bridges as well as bad maintenance, steel‐concrete bridges are now in a critical state and urgent repairs of those structures are needed. In this article progressive methods of retrofitting existing concrete bridges are shown. In the presented method, the original pillars and original bridge deck will remain in their place, and on the existing deck new composite, steel‐concrete bridge deck with encased steel members of progressive shape will be created. This method brings significant cost reduction for such retrofitting and enables the application of increased loads on the bridge.

Defect management of hospital buildings

Healthcare organisations are increasingly recognising the need to improve building performance in order to improve health care delivery, profits, and to reduce penalties. Hospital maintenance organisations are under constant pressure to plan maintenance work due to a shortage of funds on account of huge catalogues of defects in hospital buildings. While investments in hospital building maintenance are increasing, the requirement to increase building performance and user satisfaction is also increasing. The nature of building faults and the factors that influence hospital building maintenance management in Malaysia were explored. Primary data were collected through structured interview techniques involving six hospital maintenance organisations. According to the results of a survey interview involving six hospitals, water seepage, cracks, peeling paint, broken ironmongery, pipe leakage, damaged plasterboard, and discoloured paint are all widespread in hospital structures, according to the results of a survey interview involving six private and public hospitals. The key aspects that determine the maintenance management practise of hospital buildings are user attitudes, misuse/abuse, weather, and bad maintenance practice. The data revealed that hospital building users are demanding improved building performance through enhanced maintenance management service delivery. Implicit in the findings of this research is the lack of effective maintenance organisations. It is necessary to reorganise the hospital's maintenance organisations. From an ontological standpoint, the main findings of this study are generalizable to other hospitals and building typologies in and outside of Malaysia.

WITHDRAWN: An efficient framework for identifying current open issues to prevent human errors in maintaining power plants: Research gap

The competition in the energy market involves the development of environment-friendly and high scale power output plants. The major types of reliable power generation plants are found to be nuclear and hydropower plants which are manifested as a promising source of energy that produces power on a large scale. Human errors are mainly occurring during the maintenance, design (planning), and operation phases. Such errors are the main causes of performance degradation by imposing economical and technical losses. This paper keen on investigating the human error causes that lead to performance degradation in power plants. It was realized that human error is mainly caused by bad human resources strategies, experience, time Pressure, motivation, maintenance culture, and faulty materials (monitoring tools) while studying the same over two nuclear and one coal-fired power plants. This research contributes to strengthening and filling the literary gap by investigating human errors in the maintenance of power plants to identify future studies and identify current open issues on human error in power plants.

Building a blockchain for aviation maintenance records

The objective of this paper was to create a proof of concept for a blockchain application in aviation world, with an emphasis on improving the aircraft maintenance traceability. It is well known that aviation industry manages incredible complex systems, where failure is not an option. This industry needs blockchain technology not only for safety improvements but also for a new business model where airline companies can deliver more trust and more transparency to their customers.Nowadays, the passengers who are the end customers, cannot evaluate an airline company from the point of view of fleet maintenance. Bad or uncomplete maintenance are premises for an undesired accident. Moreover, aircraft investigators and auditors are experiencing difficulties in understanding how an aircraft was operated. Thinking of forecasting defects, models of predictive maintenance cannot be developed if accurate data are not available. All these can be changed with the implementation of the proposed blockchain application.Beside the theoretical explanations, the scope of this work was also to put in practice the main blockchain features and develop on a small scale, a real decentralized blockchain application using Python programming language. The script was designed to run on a localhost machine and store maintenance records and relevant parameters for the process of tracking an airplane’s lifespan in a chain of interconnected blocks.Therefore, the traditional approach in the data management is no longer an option for the aviation industry.

Pembuatan Program Aplikasi Laporan Perawatan Korektif Laboratorium Pemesinan Polman Babel

Politeknik Manufaktur Negeri Bangka Belitung is university that provide education and training in the field of engineering where there are machinery and equipment as a means of learning. The good maintenance of machine and equipment is the most important to support the learning activities. However the bad maintenance will cause disadventages for company benefit. During this time corrective maintenance is handled in a manual that is recorded in books that causes data repairing of machine is not documented well. Based on this improvement and maintenance of existing system development should be pursued in order to improve the administration system of care maintenance. The system design is oriented for creation of database applications that are expected to solve the problem.

A model of particulate matter dispersion from unfiltered air conditioner indoor

The air conditioner is used not only for indoor temperature control but also as a particulate filtering system. However, bad maintenance of the air conditioner would lead to the damage of the filtering system. The result is a bad indoor air quality due to particulate matters depositing from outdoor. By the fact that a room with an air conditioner system is isolated, the risk of the human to be exposed is high. In this research, we built a model to simulate the particulate dispersion from air conditioner without active filtering system to find the effective range of the exposure. The research is purposely to model particulate matters, especially for PM2.5 and PM0.1. The model was built in the Navier-Stokes equation for incompressible fluids by using a Lagrangian approach in the grid system. The model simulated the dispersion of particulate matters in an 8 × 8 × 3 m room with a single air conditioner. The temperature of the room was settled at 24°C without any external particulate source. The speed of the airflow was set at 3 m/s while the concentration of the PM was set by change the air conditioner temperature setting. In the simulation, we found the increase of the effective range of particulate matters in the function of time. In the initial condition, the particulate matters are dispersed into the ceiling with the highest concentration. In the less than 5 minutes, our simulation shows the particulates dispersing in the whole room in the varied concentration. In the minute 50th, the concentration is similar to the air conditioner exposure. Our measurement in real condition showed a similar condition by a maximum different of 15% than the simulation both in the dispersion time and 2.5% in the concentration. These results were achieved after we compared the simulation in t time concentration with the real particulate dispersion in the identical room dimension with the simulation. In conclusion, the model can be performed to simulate an indoor PM dispersion from non-filtering air conditioner well.

Evaluation of the Operational Speed for Iraqi Railways Using Geomatics Techniques

Theresearch evaluation is the current operational speeds of Iraqi railway lines within Geomatics techniques . It aims improving operational speeds where fined the level of speeds in Iraq has reached in some places to (5 km/h) for the north line. Also determining the factors affecting the speed and causing the decline of the railway, such as soil, the old design of line, the large number of irregular crossings, bad maintenance of fences, means of communication is very bad and almost without safty fences , a single line, except some lines and some climate element which reflected negatively on the performance of the railway, the large number of accidents with operational speed of passenger trains ranged between (20-90) km/h at a time (10) hours for the south line, and (20-80) km/h for north line. it is improved by reducing the time on the orders of caution, time to enter and exit from the station, stop at the stations time, increasing operational speed up to (80-90) km/ h, these improvements one possibly achieved by raising the irregular crossings or convert regular crossings to overpass , treatment of soil, good maintenance (for the rail lines, the protective fence), and the use of modern communication and signals system. A proposal to reduce the trip time from Baghdad to Basrah to (5.13) hour at a percentage 23% to (98-110.7) km/h(because it’s the only working line) as in the case at India where a study for upgrading track standards of conventional track with diesel and electric traction which is close to the specifications of the reality case of the Iraqi railway nets .

The Influence of Eco Maintenance on Power Consumption of the Lathe Machines

Generally, a maintenance process of a machine tool is oriented to maintain its reliability and availability in a relation of its productivity. This productivity will make a direct impact on the economic aspect of its plant. Ecomaintenance is a maintenance concept which sees maintenance in a different perspective. There is another effect on a machine that is maintained well on the environmental aspect beside its benefit of technology and economic aspects. If a machine is maintained with a proper maintenance, it will have a performance suitable with its age design condition. A machine with a good maintenance generally has a minimum rate of pollutant and waste which is possible emerging from the machining process. Then, if it uses for a machining process, it will produce a good quality product on its surface roughness and dimension accuracy. The electrical energy consumption of the machine also can be saved. It means that the GHG which usually emerges from the process of electrical energy generation in the power plant can be minimized, also the coal as fuel can be saved. The result of experiment has proven that the machine with bad maintenance will consume the electrical power higher in range 10%-60.81% than the machine with a good maintenance.

Toxoplasma gondii: Pig seroprevalence, associated risk factors and viability in fresh pork meat

This study was conducted on 161 fattening pig farms located in Aragón (Northeast Spain). Serum samples from 1200 pigs were tested for antibodies against T. gondii by indirect immunofluorescence assay (IFA). Antibodies to T. gondii (≥1:20) were detected in 301 pigs (24.52%). The seroprevalence observed in the present study indicates a widespread exposure to T. gondii, as seropositive pigs were found in 96.67% of the farms studied although low pig titers were determined. Risk factors associated with T. gondii seroprevalence were presence of cats in or around the farms, presence of dogs around the facilities, low number of animals in the farms, poor hygiene and bad maintenance of the farms. Finally, it was observed that where rodent baits were used, Toxoplasma prevalence was lower. Risk management measures including control of cats and rodents on the farms, among others, could help to reduce the observed prevalence levels. By mouse bioassay, T. gondii was detected in 73.7% and isolated from 42.1% of seropositive pigs and a significant relation between the titers of pigs and the presence and viability of T. gondii in the tissues was found. The detection of T. gondii is not possible by currently practiced meat inspection. Nevertheless, the increased probability of detecting viable forms of T. gondii in tissues of pigs with titers ≥1: 80 could be used as the cutoff for discriminating higher risk animals, and could be used as an effective control tool for the industry of cured meat products. In practical terms, we propose that this value could be used as a critical limit in the HACCP system.

Public Space in the Residential Areas: The Method of Social-spatial Analysis

The article presents the method of social-spatial analysis of public spaces within housing estates. The method was designed to identify how to formulate a strategy to improve the quality of public spaces in housing estates, and how to take into account the specific social determinants that are associated with public space in a planning process (land development plan). This method have been developed and implemented at the Faculty of Architecture of Poznan University of Technology and have been applied to several housing estates’ regeneration projects in the Poznan Municipal Area. The current condition of public spaces in housing estates is highly unsatisfactory. This is due to many factors, like faulty use of existing public spaces, low quality of public spaces, inadequate size of public spaces for the number of residents, bad maintenance and conservation of public spaces, etc. Most of these problems arise from lack of insight into the needs of the residents and awareness of the importance of public space for the community living in an estate. As such, the main point of the method presented here, is to analyse the social determinants that are related to the needs of residents. In this approach, the basic rules describing the relationships between a community of residents and a public space include specific set of indicators related to residents’ sense of identity.

중소형 보일러의 안전성 향상에 관한 연구

보일러 폭발 등의 사고에 심각한 영향을 미치는 결함이 높은 위험도가 있음으로 사고가 발생되는 것이다. 보일러의 사고발생은 78년도부터 06년까지 총 100건 사고에 379명의 사상자가 발생하였고, 그 규모가 줄지 않고 지속적이고 대형화하고 있다. 보일러 사고의 원인 결함을 분석한 결과 관리부주의로 인한 사고가 54건으로 저수위로 인한 사고 18건 제외한 총 82건 사고의 72%를 차지하고 있다. 외국의 사고내용을 분석한 결과도 또한 비슷한 수치이다. 손상이나 사고원인의 대부분이 취급과 유지 보수 불량에서 기인되는 것은 예전이나 지금이나 변함이 없었다. 검사를 받은 보일러도 사고내용을 분석한 결과 자동제어장치, 안전장치 등의 취급부주의 및 관리부실에 의한 것으로 분석 되었으며, 대형 파열사고에서는 가장 큰 원인결함은 저수위사고가 가장 큰 영향을 미친다는 것을 확인할 수 있었다. The accidents related to boilers are caused by defects with high risk which can lead to the explosion of the equipment. The number of boiler accidents from 1979 to 2006 is 100 andthe casualties totaled 379, and the scale of accidents has been growing larger every year. The analysis has found that the number of accidents caused by carelessness in management is 59, 72% of total 82 cases and 18by low level of water. The analysis of accidents in foreign countries showed a similar result. From the past till today most of the accidents have been resulted from bad handlingand maintenance. The analysis of accidents for the inspected boilers also showed that the major cause of the accidents was bad handling and maintenance of automatic controllers, safety devices, etc. And in the large-scale explosive accidents, the number one cause of them was the low level of water.

How can we use the information provided by process safety performance indicators? Possibilities and limitations

To make further progress towards a safer industry, process safety performance indicators are indispensable. There are, however, some challenges involved with interpretation of indicator outcomes. By going too far in detail one loses overview, but in not noticing the important detail a false impression of safety may be obtained. Aggregation from a detailed level upward may give relief at this point, but what to do if indicator values do not improve any further? Is there a means to relate indicators to the plant's risk level? The paper will show that when making use of the new technique of Bayesian networks for risk management, progress may be made. It seems possible to relate technical failure rates with risk factors acting over time duration and to take action before something breaks down. While originating in bad design, operation, maintenance, or neglect, these risk factors are influenced in the background by organizational, management, and human factors, which are subject to indicator monitoring. An example will be given of results one can expect when the dependencies are modeled in Bayesian network fashion. Current developments in other areas such as in aviation and offshore platform maintenance appear to be advancing in the same direction.

Study on the Technology Coefficient of Supporting for Deep Coal Mine Tunnels

To keep the stability of tunnel’s surrounding rock, and control the deformation of surrounding rocks and reduce the maintenance cost of tunnel in maximum, this article did the following aspects. Aiming at large pressure , large deformation , bad maintenance state in deep coal mine tunnel , joint cable anchor support technology is adopted , and the coordination deformation of tunnel is accomplished through anchor net-surrounding rock and its coupling with the anchor cable .Through the theoretical calculation and numerical simulation of cable anchor coupling support ,we determine reasonable technology coefficient of bolt supporting and verify the correctness of support coefficient by field observation.

Applying Geographic Information System (GIS) for Maintenance Strategy Selection

Spatial technologies, such as Geographic Information Systems (GIS), are particularly appropriate for integrating road- way data and enhancing the use and presentation of these data for highway management and operation by using spatial relationships to relate geographic and geometric objects and events. To different degrees, roadway management problems, such as pavement management, involve relations between objects and events located in different spatial positions. Because the data used in the decision-making process have spatial components, the use of spatial technologies emerges as a very appealing alternative. Spatial technologies may enhance the analysis of several transportation-related issues and may improve the quality of the decision-making process. This paper built a GIS based system that provides information for use as a platform on which all aspects of the Pavement Maintenance and Management System (PMMS) process can be built. The resulting system, GPMMS, represents a significant enhancement of all aspects of the PMMS process. A variety of spatially integrated data are important to pavement management decision making. GIS technology is shown to be the most logical way of relating these diverse, but relevant, data. In this paper, 23 sections is selected along the roadways of Nahrain University and all these sections are distresses due to different causes like weathering, ageing, traffic load, and also the bad maintenance, etc. The PSI of these sections in the range between 1 to 4, and most of these sections in the low range (between 1 to 2). That cause of need to future developments including other elements of a road maintenance management system should be considered. Completion of the whole roads database with all the types of surveys recorded i.e. all distresses, construction and maintenance history and so on.

방사선치료 시 자세와 device에 따른 호흡신호의 분석

방사선 치료에서 일정한 호흡주기의 유지가 필요한 흉부 및 복부를 치료할 때 환자의 자세와 belly board device의 사용 여부에 따라 다르게 나타나는 호흡신호의 차이를 통계적으로 분석하여 임상적용에 관한 유용성을 검정하였다. 호흡주기유지는 supine 자세에서 비교적 양호하게 나타났으며, prone 자세에서 호흡주기 유지가 양호하지 않은 경우에 belly board를 적용하여 85%가 유의하게 다른 패턴의 호흡주기를 보였고, 57%는 호흡주기 유지가 양호하게 변화한 것으로 나타났다. 각 피험자의 비만도와 체중에 따른 호흡주기유지 안정성의 차이는 보이지 않았으며, 안정성의 상대적 비교지수로 분석한 시간의 흐름에 따른 호흡의 안정성 유지는 supine 자세에서 비교적 안정적이었으며, 호흡주기 유지의 검정통계결과와 일치하였다(p=0.044, kappa=0.607). 흉부 및 복부 심지어 골반의 방사선치료에서도 호흡에 의한 환자의 움직임은 중요한 고려사항 중 하나이다. 환자의 치료부위와 target의 위치, 예상되는 plan의 beam arrangement에 따라, 환자의 자세 및 device의 여부가 결정되지만, 본 연구와 같이 호흡신호의 통계적 분석과 이의 적용을 통해, 호흡유지에 최적의 자세, belly board와 같은 device 사용여부를 결정하여, 호흡주기의 유지 및 호흡의 안정도 유지에 기여할 수 있을 것으로 사료된다. This study statistically analyzed the difference of the stability of maintaining a respiratory period shown according to position and use of a device to search the tendency and usefulness of a device. The supine position showed better maintaining respiratory cycles than the prone position. The 85% of subjects who showed bad maintenance pattern of a respiratory cycle were significantly different pattern with using belly board. It could be said that there was a significant correlation between the maintenance of a respiratory cycle and relative index of respirational stability(p=0.044, kappa=0.607). The movement due to respiration was one of important considerations in the radiation therapy on chest, abdomen, and even pelvis. This study could contribute to the high quality radiation therapy by statistic analysis of respiratory signals and its application.

ENGINEERING MANAGEMENT OF SURFACE DRIP IRRIGATION SYSTEMS

Recently maintenance operation is considered one of the main axes of engineering management of pressurized irrigation systems. There for the aim of this research work was to select the most suitable maintenance programs to improve drip irrigation systems laterals performance, and decrease the damages caused by emitter clogging as a result of bad maintenance applications. The physical maintenance programs included lateral end flushing with two different operation times5, 10 minutes at the end of each irrigation, at four interval times weekly, Bi-weekly, monthly, and at the end of each season. The flushing 5minutes was applied once continuous, and the other intermitted. The systems performance was evaluated through three parameters: discharge, clogging, and pressure through seven evaluation criteria mentioned in the research. The results showed that bi-weekly flushing for 5 min. continuously (MS1P12) proved to be the best flushing with fresh water program which decreases clogged emitters 44.21 % to be closer to the standard (control) with 4.85 %. Also partially clogged emitters decreased by 46.7 %, Emission uniformity(EU%) increased 19.4 %, and distribution uniformity(DU%) 13.9 % more than the control treatment. (MS1P12) was followed by the weekly flushing for 10 min. continuously. (MS3P11) as it raised (DU%) with 12.3 % and gave the highest value of pressure uniformity (UP%) that reaches 93.14%.

Traumatic spinal cord injuries in Ile-Ife, Nigeria, and its environs

In Ile-Ife, Nigeria, traumatic brain injuries are largely due to traffic accidents caused mainly by the bad maintenance of the roads and unsafe driving. Young men in the productive stage of their lives are those most affected. The resultant disabilities include quadriplegia (in more than half the patients) and paraplegia. The cost of treating and providing adequate facilities for these patients imposes a heavy economic burden upon developing countries.

Failure analysis of boiler cold and hot reheater tubes

An analysis was made on the failure and shut down of boiler cold and hot reheater tubes by chemical analysis of sediments, metallographic examinations, XRD, SEM and EDX studies. The mode of operation, maintenance, and feed water chemistry were also checked. It is concluded that the bad maintenance and feed water chemistry are the main causes of the failure, leading to various types of corrosion mechanisms, which are identified and discussed in this study.