Showing 4 results for sharifi
Zahra Sharifi, Reza Osqueizadeh, Seyyed Farhad Tabatabai Ghomshe,
Volume 3, Issue 1 (Journal of Ergonomics 2015)
Abstract
Introduction: Job satisfaction and productivity among industrial workforce depend on multiple factors. Among these
factors, designing the workstation based on bodily characteristics and dimensions of the workers is of critical
significance. Since industrial chairs have direct impacts on biomechanical and anthropometric compatibility, they play
a major role in enhancing workers’ interaction with their workplace. The current study approached the redesign of such
a product with a focus on ergonomics.
Materials and Methods: The present research was a typical combined design project. In the quantitative phase, 90
participants underwent 12 anthropometric measurements (which were important in designing industrial chairs). The
underlying cognitive aspects of the question were evaluated via qualitative methodologies.
Results: Since normal distribution of the data was confirmed, raw anthropometric data were descriptively processed
and reported. Cognitive assessments revealed correlations between correct form and softness of the backrest, and
appropriate slope of the seat-pan, being a main factor determining the level of comfort while interacting with industrial
chairs.
Conclusion: Diverse physical constraints and conditions caused by the variety of duties and workstations have made it
somehow difficult for specialists to design a universal industrial chair functioning in all different contexts.
Nevertheless, the current study confirmed the effectiveness of involving personnel in redesigning the workplace and
easing the challenges.
Majid Fallahi, Majid Motamedzade, Zahra Sharifi, Rashid Heidari Moghaddam, Alireza Soltanian,
Volume 4, Issue 3 (Journal of Ergonomics 2016)
Abstract
Introduction: Advances in technology and the use of complex systems at work have imposed high mental workloads to operators; so, continuous monitoring of mental workload can help to prevent mental problems and maintain mental health. Therefore, this study aimed to investigate the impact of mental workload on physiological and subjective responses.
Methods: This cross-sectional descriptive-analytical study was performed on 16 healthy university students in 2014 at a laboratory setting. Physiological parameters of surface electromyography and electrocardiography in six blocks (resting, high mental work, moderate, low, very low and recovery) were measured using NeXus-4. After performing each block, the NASA-TLX questionnaire was completed. Statistical analysis was conducted using SPSS software version 21.0. A 5% significance level was adopted in all the tests.
Results: The results showed significant differences for the average score of NASA-TLX between the different levels of mental work load (P < 0.05). Also, the analysis of repeated measures variance showed significant differences for heart rate and heart rate variability parameters in the six blocks (P < 0.05), but no significant difference was observed for the shoulder muscles activity.
Conclusions: Different levels of mental work load can impact on people's subjective responses and some of their physiological responses. Thus, in such workplaces, it will be necessary to conduct an ergonomic program to manage mental health.
Zahra Ordudari, Shiva Soury, Ehsanollah Habibi, Zahra Sharifian,
Volume 6, Issue 2 (Journal of Ergonomics 2018)
Abstract
Introduction: Regular physical activity plays an important role in the prevention of low back pain, osteoporosis, cardiovascular disease, obesity, diabetes, cancer, hypertension, depression and early death. Also, work ability is related to the interactions between physical and mental ability, working conditions, employee efficiency, and employee health status. In this research, the relationship between work ability and the level of physical activity is investigated.
Materials & Methods: This study was descriptive-analytical and cross-sectional, which was conducted among 120 office workers and operatives. Physical activity and work ability index were measured using physical activity questionnaire and Iranian version of work ability index. Data analysis was performed using SPSS20 and (P <0.05) was considered significant.
Results: In this study, gardeners and office workers respectively,had the highest and lowest levels of physical activity with the mean of 4206.09 and 3567.58. However, work ability almost was the same in all groups. Also, Pearson correlation coefficient showed that there was no significant relationship between work ability index and physical activity.
Conclusion: According to the results,the work ability index of subjects was good and physical activity was high. Also, there was no significant relationship between work ability index and physical activity, thus making plans to promote the work ability index should be a priority in the intervention program.
Zahra Sadat Sharifi, Rasoul Hemmatjo, Abolfazl Ghahramani,
Volume 13, Issue 3 (Iranian Journal of Ergonomics-In Press 2025)
Abstract
Background and Objectives: Nowadays, electronic devices such as computers, mobile phones, and tablets have played an important role in people's work and lives, and the main complaint of users of video terminals is eye symptoms caused by them. This study aimed to evaluate the intensity of lighting and brightness and its possible relationship with visual fatigue in users of video terminals at Tabriz University of Medical Sciences.
Methods: This cross-sectional study was conducted on 171 users of video terminals at Tabriz University of Medical Sciences. In this study, the local illuminance intensity at the work surface and the luminance intensity from the screen at the user's eye level were measured. A 15-question visual fatigue questionnaire was used to assess visual fatigue. The results were analyzed using paired t-tests and chi-square tests using SPSS software.
Results: In this study, the average local illumination intensity on the desk was 306.6 lux and the average luminance intensity was 73.9 candelas per square meter. Local illumination intensity was lower than the recommended level in 41.6 percent of cases. There was no statistically significant relationship between illumination intensity and users' vision during the study, and there was also no statistically significant relationship between users' luminance and vision. The results of this study showed that vision at the end of the work has a significant relationship with the individual's vision at the beginning of the work. The results of this study also showed that there is a significant relationship between visual fatigue and the type of work.
Conclusion: According to the findings of the study, it is recommended that, if possible, the time to start working with visual terminals should be when there is no feeling of visual fatigue. Also, since one of the factors affecting visual fatigue is the type of work, it is recommended that users manage their work in such a way that they are mostly inactive (reading the page).
