• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.2
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• pp.110-122
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• 2006

Objective : This study was conducted to quantify chronic lead exposure from various media(ie. working environment, food, ambient air), and to certify the usefulness of exposure assessment using Monte-Carlo simulation in the fields of occupational health. Methods : Data were obtained from Korean Industrial Health Association, Korea Food and Drug Administration, and the Ministry of Environment. Then lead worker's exposure was estimated indirectly from various media and parameters (ie. volume inhaled, body weight, dietary intake, etc.). Uncertainty was analyzed by Monte Carlo simulation with Crystal Ball software. Exposure doses and hazard indices were simulated with various hypothetical scenarios including weekly working hours and respiratory protective equipment. Results : Without respiratory protective equipment, the total exposure dose per kilogram of body weight of lead workers was estimated as $5.45{\times}10^{-3}mg/kg/day$, and hazard index was estimated as 2.26, and exposure contributions were calculated as follows : working environment(82.42 %); foods(17.57 %); and ambient air(0.01 %). But, if working condition has changed - reduction of working hours and using respiratory protective equipment, the total exposure dose per kilogram of body weight was estimated between $1.34{\times}10^{-3}-1.49{\times}10^{-3}mg/kg/day$, and hazard index was estimated between 0.56 - 0.62. Conclusions : This study suggested that occurrence of hazardous impact(ie. increased blood pressure) through lifetime lead exposure would be expected, and that the Monte-Carlo simulation was useful for the fields of occupational health.

• Composites Research
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• v.28 no.6
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• pp.348-355
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• 2015

NDT (Non Destructive Test) of the adhesive joints is very important because their strengths have greatly affected by the worker's skill and environmental condition. Recently, the electric impedance method in which 1-2 wt% CNT was dispersed in the adhesive and the electric resistance of the adhesive joint was measured was suggested for the defect detection of the adhesive joint. The uniform dispersion of CNT in the electric impedance method is very important to make a constant electric resistance of the adhesive joint and the accuracy of defect detection depends on the uniform dispersion. In this paper, the adhesive joints in which CNT was dispersed in the adhesive by the four dispersion methods were made and their electric resistance were measured. The pre-process and evaporation process of CNT using the ultrasonic method and agitation method was used and the effective dispersion method was suggested. Also, the criteria to evaluate the dispersivity was proposed.

• Genomics & Informatics
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• v.19 no.4
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• pp.49.1-49.11
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• 2021

Nowadays, Genomic data constitutes one of the fastest growing datasets in the world. As of 2025, it is supposed to become the fourth largest source of Big Data, and thus mandating adequate high-performance computing (HPC) platform for processing. With the latest unprecedented and unpredictable mutations in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the research community is in crucial need for ICT tools to process SARS-CoV-2 RNA data, e.g., by classifying it (i.e., clustering) and thus assisting in tracking virus mutations and predict future ones. In this paper, we are presenting an HPC-based SARS-CoV-2 RNAs clustering tool. We are adopting a data science approach, from data collection, through analysis, to visualization. In the analysis step, we present how our clustering approach leverages on HPC and the longest common subsequence (LCS) algorithm. The approach uses the Hadoop MapReduce programming paradigm and adapts the LCS algorithm in order to efficiently compute the length of the LCS for each pair of SARS-CoV-2 RNA sequences. The latter are extracted from the U.S. National Center for Biotechnology Information (NCBI) Virus repository. The computed LCS lengths are used to measure the dissimilarities between RNA sequences in order to work out existing clusters. In addition to that, we present a comparative study of the LCS algorithm performance based on variable workloads and different numbers of Hadoop worker nodes.

• Safety and Health at Work
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• v.14 no.2
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• pp.193-200
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• 2023

Background: International evidence shows that mining workers are at greater risk of suicide than other workers; however, it is not known whether this applies to the Australian mining sector. Methods: Using data from the National Coronial Information System, rates of suicide among male mining workers were compared to those of three comparators: construction workers, mining and construction workers combined, and all other workers. Age-standardized suicide rates were calculated for 2001-2019 and across three intervals '2001-2006', '2007-2011', and '2012-2019'. Incidence rate ratios for suicide were calculated to compare incidence rates for mining workers, to those of the three comparative groups. Results: The suicide rate for male mining workers in Australia was estimated to be between 11 and 25 per 100,000 (likely closer to 25 per 100,000) over the period of 2001-2019. There was also evidence that the suicide rate among mining workers is increasing, and the suicide rate among mining workers for the period 2012-2019 was significantly higher than the other worker group. Conclusions: Based on available data, we tentatively deduce that suicide mortality among male mining workers is of concern. More information is needed on both industry and occupation of suicide decedents in order to better assess whether, and the extent to which, mining workers (and other industries and occupations) are at increased risk of suicide.

• The Journal of the Korea Contents Association
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• v.22 no.8
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• pp.503-517
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• 2022

The research results can be summarized in two ways. First, it was confirmed that the provision of public care services for elementary school children had a statistically significant effect on the reduction of children's participation in private education. Second, it was confirmed that the provision of the services had a statistically significant effect on the reduction of children's private education expenses regardless of the mother's economic activity status. Based on this, this study drew the following policy and practical suggestions. First, it is necessary to expand the provision of the services in order to reduce the burden of childrearing of 'working mothers' raising elementary school children. Second, it is necessary to improve quality of the services. To do this, policy-wise, integrated management of services and improvement of treatment of service providers must be made. In the field, it is necessary to improve quality of the services by providing worker education and supervision.

• Safety and Health at Work
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• v.14 no.4
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• pp.384-389
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• 2023

Background: Exposure to welding fume is associated with adverse effects on worker health. The use of various control measures can reduce levels of exposure and the resulting health effects. However, little is known about the factors that may influence workers' use of control measures in the workplace and their perceived intervention needs. This study aimed to investigate workers' and other stakeholders' views on ways to improve the use of welding fume control measures in Australian workplaces. Methods: We conducted a series of online focus group discussions and individual interviews with participants who have some occupational involvement in welding, whether as workers, employers or industry representatives, union representatives, or regulators. A semi-structured question guide was used, and all discussions and interviews were recorded and transcribed for analysis. Results: Five focus group discussions and five individual interviews were conducted with a total of 21 participants. Three major themes emerged. The first addressed the current awareness of welding fume harms and concern about exposure; the second focussed on the current use of control measures, and barriers and facilitators to their use; and the last centred around intervention needs and the contents of a potential effective intervention. Conclusion: Improving the use of control measures to prevent exposure to welding fume requires knowledge around the barriers and facilitators of control, use, and the intervention needs of stakeholders. This study has provided such knowledge, which will facilitate the design and implementation of an intervention to reduce welding fume exposure and ultimately protect the health of workers.

• Korean Journal of Human Ecology
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• v.7 no.1
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• pp.51-67
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• 2004

This study analyzed the effects of nutrition technicians' hygiene education on cooking workers' performance of hygiene management in order to ensure the security of school meals. The situation of cooking workers' disposition in subject schools was elementary school(51.1%) and middle school(48.9%) and the type of meals was rural area type(54.2%), urban type(36.5%). and island and isolated area type(9.3%). The methods of meals management were single cooking(88.2%) and joint cooking and management(11.8%). The type of distributing meals was distributing in a dining room(93.5%), in a classroom(3.7%), and in both dining room and classroom(2.8%). Nutrition technicians' employment form included regular(53.5%) and daily(88.2%). Their education was junior college graduate(50.2%), university graduate(44.8%). and graduate school students(5.0%). Cooking workers' employment form included daily(88.2%) and regular (11.1%). suggesting that most were regular. Most cooking workers(77.4%) had at least high school certificate. Regarding the situation of cooking workers' disposition in subject schools, the number of student per one cooking worker was found as 91-120(37.2%), 61-90(22.6%). 60 and under(21.l %). 121-15006.7%). and 151 and over(2.5%). Cooking workers' level of performance of hygiene management was post-working stage(66.37/75 marks), pre-working stage(64.22/75 marks). and working stage(20.34/25 marks), The counting of meals articles in a pre-working stage(20.34/25 marks). temperature and required time in a working stage(18.78/25 marks), and machinery equipment and hygiene in a pre-working stage(21.40/25 marks) showed lowest of performance, which suggest poor service of hygiene. Cooking workers' performance of hygiene management by working stage showed the significant difference with school class(p<.001), type of schools with meals(p<.05). state of cooking workers' employment(p<.001), and cooking worker's disposition(p<.05). A working stage showed the significant difference with type of schools with meals(p<.05). A post-working stage showed the significant difference according to type of schools with meals(p<.05), and the methods of meals management(p<.05), and cooking workers' disposition(p<.05). In the execution of hygiene education, individual hygiene was highest(94.8%), followed by the management of machinery equipment and tools(89.7%), food poisoning and microorganism(94.7%), and the method of food treatment(76.4%). A yearly plan of hygiene education included established(83.9%) and not established(l6.1%). Regular education included not executed(25.1%), 2-3 times a month(l6.1%), and more than 4 a month(4.0%) and occasional education was not executed(57.0%), 1-3 times a month(26.3%), and more than 4 a month(l5.7%). In the methods for hygiene education, oral education(95.7%) was used most, followed by demonstration(10.5%), poster/photo(10.5%), video/slide(3.7%), and computer(3.7%). Frequency of improvement and complement of hygiene education included once a month(56.3%), once a year(20.7%), by quarter(l1.5%), and every six months(1l.5%). Newspaper was used most in materials of hygiene education, followed by internet, TV, nutrition technician's reeducation, information exchange between members, educational office's training, and reference book, and educational office's material. and symposium. Cooking workers' assessment of the effect of hygiene education was conducted through observation(56.8%), check table(l5.2%), question(l4.0%), and examination(14.0%). The reason of cooking workers' low level of performance included habitual custom(53.9%), lack of understanding(20.4%), overwork(l4.6%), and lack of knowledge(l1.l%) and the reason of difficulty in hygiene education included lack of time(55.3%), lack of understanding(27.6%), lack of knowledge and information(8.7%), and lack of budget(48.0%).

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.384-398
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• 2016

The purpose of this study is to explore how school social workers recognize on the school violence of adolescents by using Q methodology. To this study, selected 31 of Q samples related school violence of adolescent by applying Q methodology and 33 of socials workers completed classification table, and three types were derived. The first type is named 'a type of improvement parents' concern with nonprofessional perception' because it has a significant part in bringing up children by parents to prevent school violence of adolescent and also has a negative perception, which is difficult to approach professional intervention. The second type is named 'a type of uncertainty of responsibility with passive perception' because there is an ambiguousness between responsibility and criteria through connection of official on the school violence. The third type is named 'a type of absence of responsibility with professional perception' because it is perceived absence of job roles to prevent school violence. This type showed school social workers, as a professionals of school violence of adolescents, wanted to intervene school violence but realistic intervention was difficult. From this study, it is considered subjective perception of school social workers on the school violence of adolescents will be affected on the change of adolescents in the future, and it is a significant way to use them as a basic data to prevent or remove school violence of adolescents in the school through conception and typology of them.

• 한국사회정책
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• v.23 no.2
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• pp.141-172
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• 2016

This study examines the employment conditions and labour experience of elementary after-school care teachers in South Korea. Based on the empirical data collected through in-depth interviews with after-school care teachers in Gwangju Metropolitan City, the study considers multifaceted problems faced by after-school care teachers in their workplace. The after-school care class is part of educational policies initiated and rapidly expanded by the Ministry of Education, resulting in the substantial increase of non-regular school workers. The irregularization of after-school care teachers illustrates that the common problems faced by female non-regular workers, such as social discrimination, exclusion and inequality, are also transplanted into the typical public sector. In the case of Gwangju Metropolitan City, during the past two years there have been evident increases both in under 15-hour short time contract care teachers and outsourcing of care classes. Temporary part-time contract care teachers suffer relentless job insecurity and experience poor working conditions, exclusion and discrimination within the workplace and labour alienation. In order to minimize the organized resistance of care teachers, school authorities implicitly individualize and isolate care teachers through hierarchization, the division of labour and the spatial division of classes between indefinite and temporary contract teachers.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.5
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• pp.275-280
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• 2002

In order to control glucose concentration during fed-batch culture for antibiotic production, we applied so called “software sensor” which estimates unmeasured variable of interest from measured process variables using software. All data for analysis were collected from industrial scale cultures in a pharmaceutical company. First, we constructed an estimation model for glucose feed rate to keep glucose concentration at target value. In actual fed-batch culture, glucose concentration was kept at relatively high and measured once a day, and the glucose feed rate until the next measurement time was determined by an expert worker based on the actual consumption rate. Fuzzy neural network (FNN) was applied to construct the estimation model. From the simulation results using this model, the average error for glucose concentration was 0.88 g/L. The FNN model was also applied for a special culture to keep glucose concentration at low level. Selecting the optimal input variables, it was possible to simulate the culture with a low glucose concentration from the data sets of relatively high glucose concentration. Next, a simulation model to estimate time course of glucose concentration during one day was constructed using the on-line measurable process variables, since glucose concentration was only measured off-line once a day. Here, the recursive fuzzy neural network (RFNN) was applied for the simulation model. As the result of the simulation, average error of RFNN model was 0.91 g/L and this model was found to be useful to supervise the fed-batch culture.