Orhan Korhan

Application of fuzzy fault tree analysis based on modified fuzzy AHP and fuzzy TOPSIS for fire and explosion in the process industry

This study aimed at establishing fault tree analysis (FTA) using expert opinion to compute the probability of an event. To find the probability of the top event (TE), all probabilities of the basic events (BEs) should be available when the FTA is drawn. In this case, employing expert judgment can be used as an alternative to failure data in an awkward situation. The fuzzy analytical hierarchy process as a standard technique is used to give a specific weight to each expert, and fuzzy set theory is engaged for aggregating expert opinion. In this regard, the probability of BEs will be computed and, consequently, the probability of the TE obtained using Boolean algebra. Additionally, to reduce the probability of the TE in terms of three parameters (safety consequences, cost and benefit), the importance measurement technique and modified TOPSIS was employed. The effectiveness of the proposed approach is demonstrated with a real-life case study.

Work-related musculoskeletal discomfort among heavy truck drivers

Background. Heavy truck drivers are exposed to various psychological, psychosocial and physiological factors, some of which can cause musculoskeletal discomfort in different body regions. Purpose. This study aims to investigate the correlation between different factors of musculoskeletal discomfort in heavy truck drivers. Methods. A cross-sectional study design was applied. A total of 384 participants were interviewed using an updated version of the Nordic musculoskeletal questionnaire. While hypothesis testing was used to assess the association of different factors in musculoskeletal discomfort, logistic regression was applied to explore different correlations among questions of the survey. Results. The results demonstrate that hours of exposure to vibration were associated with discomfort in the neck and shoulders (p < 0.001). This relationship was not statistically significant in the lower back area (p = 0.300). Additionally, 19 equations, their correlations and their odds ratios were formulated with Nagelkerke R2 > 0.05. Conclusion. Fifty-seven percent of the drivers were suffering from discomfort in their lower back region. Moreover, seat comfort was found to be highly correlated with discomfort in the neck, shoulder and upper back areas. Additionally, with aging the likelihood of experiencing discomfort in the neck, upper back and knees is increased.

Reducing Perceived Musculoskeletal Discomfort in Office Employees through Anthropometric Computer Workstation Design

Abstract Numerous office employees who work with computer workstations endure various musculoskeletal discomforts every day. This study intends to reduce musculoskeletal discomfort caused by desktop computer workstations, which causes productivity losses and several medical costs. A survey was distributed to 42 participants who use desktop computer workstations for at least 6 hours per day. Specific anthropometric measurements were collected to design an optimized computer workstation. Ten respondents were randomly selected to participate in an electromyogram (EMG) experiment to determine muscular impulse differences between standard and optimized desktop computer workstations. The EMG results indicated that discomforts are pronounced in shoulder, neck, lower and upper back and hand-wrist regions. The risk assessment model showed that experiencing troubles in the neck (p=0.022), shoulder (p=0.023), and wrist/hands (p=0.020) within 12 months were the significant factors. ANOVA results proved that the optimized design of a computer workstation causes less muscular pressure on the muscles at each measured body region.

Work-Related Musculoskeletal Discomfort in the Shoulder due to Computer Use

The National Institute for Occupational Safety and Health (NIOSH, 1997) in the USA defines Musculoskeletal Disorder (MSD) as a disorder that affects a part of the body’s musculoskeletal system, which includes bones, nerves, tendons, ligaments, joints, cartilage, blood vessels and spinal discs. These are the injuries that result from repeated motions, vibrations and forces placed on human bodies while performing various job actions. The individual factors that can contribute to musculoskeletal symptoms include heredity, physical condition, previous injury, pregnancy, poor diet, and lifestyle.

Physical Discomfort Experienced in Traditional Education and Tablet-Assisted Education: A Comparative Literature Analysis

With advances in technology, various forms of computers have become more involved in education. In particular, tablet computers are actively used for educational purposes nowadays. Given the fact that musculoskeletal, postural, and ocular developments of children and adolescents are still not complete, potential physical issues resulting from usage of new technologies must not be disregarded. Physical problems or challenges experienced by children and adolescent students will be involved in this research from the perspectives of traditional education and tablet-assisted education. In a sense, a comparative review of the available literature is used in the study to analyze and identify the commonalities and differences in physical problems experienced by students.

Musculoskeletal Discomfort Experienced by Children and Adolescents During the Use of ICT: A Statistical Analysis of Exposure Periods and Purposes

The risk of development of musculoskeletal discomfort problems among children and adolescents is high as the development of their musculoskeletal system is still continuing. Therefore, it is very important to learn the habits and attitudes of children and adolescents, the location and duration of the use of these technologies, and the relationship between musculoskeletal discomforts. This study aims to investigate the relationship between duration of daily exposure of children and adolescents to Information and Communication Technology (ICT) devices and the musculoskeletal discomfort experienced. A two-part questionnaire, which are adopted by Dutch Musculoskeletal Discomfort Questionnaire (DMQ) and the Student Specific Cornell Musculoskeletal Discomfort Questionnaire (SS-CMDQ), was used to gather data from children and adolescents in public and private secondary and high schools in Northern Cyprus. The survey findings showed that the participants experienced discomfort mostly in the neck, upper back, lower back, and shoulders. The correlation analysis indicated that there is a relationship between prolonged use of ICT devices for many hours and musculoskeletal discomfort. Also, it was found that there is a significant relationship between daily use of desktop, laptop, or tablet computers for different purposes (activities) and musculoskeletal discomfort. The musculoskeletal discomfort was observed to occur mostly due to the use of ICT devices for communication, surfing the Internet, reading, and writing. The results of the analysis showed that shoulder, upper back, upper arm, forearm, and hand muscles are affected by the use of ICT devices.