• Safety and Health at Work
• /
• 제14권1호
• /
• pp.59-65
• /
• 2023

Objectives: Epidemiological evidence linking long working hours and shift work to metabolic syndrome remains inadequate. We sought to evaluate the impact of reducing working hours on metabolic syndrome. Methods: We compared the prevalence of metabolic syndrome among male manual workers in a manufacturing company (N = 371) before and after the introduction of policy to reduce daily work hours from 10 to 8 hours. Components of metabolic syndrome were measured in periodic health examinations before the intervention, 6-9 months after, and 1.5-2 years after the intervention. Generalized estimating equation models were used to estimate changes in the prevalence of metabolic syndrome. Analyses were stratified by day work versus shift work. Results: The results showed a significantly decreased prevalence of metabolic syndrome 6-9 months following the intervention in day workers (risk ratio = 0.68, 95% confidence interval 0.52-0.88), but the benefit disappeared after 1.5-2 years. Shift workers showed a decreased prevalence of metabolic syndrome for the whole follow-up duration after the intervention, although the change was not statistically significant. Conclusion: Reducing working hours was associated with short-term improvement in metabolic syndrome in male manual workers.

• Journal of the Korean Society of Marine Environment & Safety
• /
• 제26권2호
• /
• pp.186-194
• /
• 2020

In this study, spectral analysis was conducted to identify environmental factors af ecting short-term changes in water temperature in the East, West and South coasts of Korea. The data used in the spectrum analysis is the 2016 summer water temperature, air temperature, tide level and wind data provided by Korea Hydrographic & Oceanographic Agency. In power spectrum results, peaks of water temperature and tide level were observed at same periods in West Sea (Incheon, Pyeungteak, Gunsan and Mokpo) and South Sea (Wando, Goheung, Yeosu, Tongyeong and Masan) where mean tidal range was more than 100 cm. On the other hand, periodicity of water temperature did not appear in East Sea and Busan where the mean tidal range was small. Coherence analysis showed that water temperature was highly correlated with tide in West Sea and three stations(Wando, Goheung and Tongyeong) of South Sea. Especially, correlation between water temperature and tide level in Wando and Tongyeong presented 0.96 at semi-diurnal period. Water temperature in Yeosu seems to have influenced by tide and inflow of fresh water. In Masan, water temperature is influenced by south wind, tide and inflow of fresh water. In East Sea, influence of tide on water temperature is small due to current and small tidal range. As a result of comparing the time series graph, stations where the correlation between water temperature and tide is high show that relatively cold water was inputted at flood tide and flow out at ebb tide. short-term variation of water temperature was affected by tide, but long-term variation over a month was affected by air temperature.

• The Journal of Korean Medicine
• /
• 제26권3호
• /
• pp.249-262
• /
• 2005

Backgrounds : As obesity prevails as an epidemic. diet programs including low-calorie diets are developed continuously. It is generally believed that a low-calorie diet is commonly followed by resting metabolic rate decrease and ultimate weight regain. Ephedra and Evodia are known to have sympathomimetic and anti-obesity effect. Objectives : This study was a prospective, double-blinded, randomized md placebo-controlled clinical trial to evaluate the effects of Ephedra sinica and Evodia rutaecarpa on resting metabolic rate (RMR), weight, body composition, and short-term safety in obese women on low-calorie diet. Methods : 125 otherwise healthy obese women (body mass Index ${\geq}\;25kg/m^2$) were recruited and randomly assigned to three groups: Ephedra group (n=41), Evodia group (n =45), and placebo group (n=39). Subjects were administered Ephedra extract in capsules (pseudo-ephedrine 31.52mg) or Evodia extract in capsules (evodiamine 6.75mg, rutaecarpine 0.66mg) or placebo capsules as well as participating in a low-calorie diet for 8 weeks, Resting metabolic rate and body composition were measured at baseline,4 and 8 weeks. Basic serum exams were performed to evaluate the short-term safety of the herbs and changes of lipid variables. Results : All three groups showed significant BMI decreases probably due to low-calorie diet. Among them, the Ephedra group manifested most prominent BMI-reducing effect and towered total cholesterol and triglycerides significantly. The RMR was not changed during the 8-week diet in all groups. No significant difference among the groups was found in RMR, either. Stbject with higher RMR than the mean at the baseline showed a tendency to keep their RMR more stable during the diet program. Conclusions : Ephedra with a low-calorie diet was effective in reducing BMI. RMR change was not compensated by herbal medicines. RMR change seemed to be affected rather by constitution and body composition than medicine. Ephedra and Evodia were proven to be safe for sort-term use in herbal form. Especially, Ephedra was effective in lowering total cholesterol and triglycerides during the 8 weeks.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• 제11권6호
• /
• pp.49-59
• /
• 2012

Recently, various alternatives for safety and efficiency of commercial vehicles have been considered, and one of the new alternatives is the application of a digital tachograph. In Korea, the installation of a digital tachograph to commercial vehicles was regulated from 2011 and Korea Transportation Safety Authority developed e-TAS to analyze the monitoring data from digital tachographs installed in the order of 100 commercial vehicles. This study performs the potential impact analysis of the DTG installation, which includes a trend of dangerous driving, a trend of traffic accidents and cost-effective analysis, a trend of fuel consumption and cost-effective analysis, a cost-effective analysis of social benefits using e-TAS data. Depending on the frequency of dangerous driving, the participants are divided into three groups; high-dangerous group, average-dangerous group and low-dangerous group. The high-dangerous driving group shows lower km/liter than the low-dangerous driving group by 15% for buses and taxis and by 30% for trucks. About $CO_2$ emission, the difference becomes bigger; 25%, 25% and 42% for buses, taxis and trucks, respectively. Although this study is a short-term period analysis, the methodology will be applicable for the long-term period analysis with larger data.

• Journal of the Korean Society of Marine Environment & Safety
• /
• 제18권6호
• /
• pp.545-550
• /
• 2012

Wind resource assessment is necessary when designing wind farm. To get the assessment, we must use a long term(20 years) observed wind data but it is so hard. so that we usually measured more than a year on the planned site. From the wind data, we can calculate wind energy related with the wind farm site. However, it calculate wind energy to collect the long term data from Met-mast(Meteorology Mast) station on the site since the Met-mast is unstable from strong wind such as Typhoon or storm surge which is Non-periodic. To solve the lack of the long term data of the site, we usually derive new data from the long term observed data of AWS(Automatic Weather Station) around the wind farm area using mathematical interpolation method. The interpolation method is called MCP(Measure-Correlative-Predict). In this study, based on the MCP Regression Model proposed by us, we estimated the wind energy at Handong site using AEP(Annual Energy Production) from Gujwa AWS data in Jeju. The calculated wind energy at Handong was shown a good agreement between the predicted and the measured results based on the linear regression MCP. Short term AEP was about 7,475MW/year. Long term AEP was about 7,205MW/year. it showed an 3.6% of annual prediction different. It represents difference of 271MW in annual energy production. In comparison with 20years, it shows difference of 5,420MW, and this is about 9 months of energy production. From the results, we found that the proposed linear regression MCP method was very reasonable to estimate the wind resource of wind farm.

• Safety and Health at Work
• /
• 제11권1호
• /
• pp.109-117
• /
• 2020

Background: Ammonia and hydrogen sulfide are harmful gases generated during aerobic/anaerobic bacterial decomposition of livestock manure. We evaluated ammonia and hydrogen sulfide concentrations generated from workplaces at livestock farms and determined environmental factors influencing the gas concentrations. Methods: Five commercial swine farms and five poultry farms were selected for monitoring. Real-time monitors were used to measure the ammonia and hydrogen sulfide concentrations and environmental conditions during the manure-handling processes. Monitoring was conducted in the manure storage facility and composting facility. Information on the farm conditions was also collected through interview and walk-through survey. Results: The ammonia concentrations were significantly higher at the swine composting facilities (9.5-43.2 ppm) than at other manure-handling facilities at the swine and poultry farms, and high concentrations of hydrogen sulfide were identified during the manure agitation and mixing process at the swine manure storage facilities (6.9-19.5 ppm). At the poultry manure-handling facilities, the ammonia concentration was higher during the manure-handling processes (2.6-57.9 ppm), and very low hydrogen sulfide concentrations (0-3.4 ppm) were detected. The air temperature and relative humidity, volume of the facility, duration of manure storage, and the number of animals influenced the gas concentrations. Conclusion: A high level of hazardous gases was generated during manure handling, and some levels increased up to risk levels that can threaten workers' health and safety. Some of the farm operational factors were also found to influence the gas levels. By controlling and improving these factors, it would be possible to protect workers' safety and health from occupational risks.

• Journal of the Korean Society of Safety
• /
• 제39권3호
• /
• pp.1-6
• /
• 2024

Polyester round slings are widely utilized in various work environments due to their lightweight, flexible nature and smooth surface that minimizes the risk of cargo abrasion or damage. However, specific guidelines intended to protect round slings from the damage caused by the sharp edges of cargo, thus preventing accidents in case the cargo falls, are lacking in South Korea. In this study, a comparative analysis was conducted on the regulations and guidelines related to round slings in South Korea and the United States. Further, experiments were carried out to determine the relationship between round slings and lifting accessories. The research identified specific shortcomings in the user manuals provided by round-sling manufacturers. Accordingly, certain measures were proposed for enhancing the operational safety of round slings: 1) establish criteria for edge protection of polyester round slings and 2) recommend standardization of the information provided by manufacturers. As developing new standards is a time-consuming task, this study proposes a method for enhancing the operational safety of round slings in the short term by introducing established safety standards from the United States-where safety has been proven over a considerable period of time-into the domestic context. In addition, it is recommended that edge criteria be permanently printed on the labels of round slings.

• Toxicological Research
• /
• 제17권
• /
• pp.293-297
• /
• 2001

The international pharmaceutical and regulatory communities had been recognizing the limited utility of conventional rodent carcinogenicity study particularly on the second species, mouse, after intense investigation of carcinogenicity data base worldwide, and a new scheme for carcinogenicity testing for pharmaceuticals was proposed at the Expert Working Group on Safety in the International Conference on Harmonization (ICH) in 1996. CB6F 1-Tg rasH2 mouse carrying human prototype c-Ha-ras gene with its own promoter/enhancer is one oj the new carcinogenicity assay model for human cancer risk assessment. Studies have been conducted since 1992 to validate the transgenic (Tg) mice for rapid carcinogenicity test-ing, short term (26 weeks) studies with genotoxic (by Salmonella), non-genotoxic carcinogens, genotoxic non-carcinogens, non-genotoxic non-carcinogens revealed relatively high concordance oj the response of the Tg mouse with classical bioassay across classes of carcinogenic agents. Mechanistic basis for carcinogensis in the model are being elucidated in terms of the role of overexpression and/or point mutation of the transgene. This report review the initial studies of validation of the model and preliminary results of on-going ILSI HESI ACT project will be presented.

• The Journal of Society for e-Business Studies
• /
• 제23권2호
• /
• pp.33-47
• /
• 2018

City gas pipelines are buried underground. Because of this, pipeline is hard to manage, and can be easily damaged. This research proposes a real time prediction system that helps experts can make decision about pressure anomalies. The gas pipline pressure data of Jungbu City Gas Company, which is one of the domestic city gas suppliers, time variables and environment variables are analysed. In this research, regression models that predicts pipeline pressure in minutes are proposed. Random forest, support vector regression (SVR), long-short term memory (LSTM) algorithms are used to build pressure prediction models. A comparison of pressure prediction models' preformances shows that the LSTM model was the best. LSTM model for Asan-si have root mean square error (RMSE) 0.011, mean absolute percentage error (MAPE) 0.494. LSTM model for Cheonan-si have RMSE 0.015, MAPE 0.668.

• Molecular & Cellular Toxicology
• /
• 제5권3호
• /
• pp.257-264
• /
• 2009

Gardenia yellow, extracted from gardenia fruit, has been widely used as a coloring agent for foods, and thus, safety of its usage is of prime importance. In the current study, short-term genotoxicity assays were conducted to evaluate the potential genotoxic effects of gardenia yellow. The gardenia yellow used was found to contain 0.057 mg/g of genipin, a known biologically active compound of the gardenia fruit extract. Ames test did not reveal any positive results. No clastogenicity was detected by a chromosomal aberration test, even on evaluation at the highest feasible concentration of gardenia yellow. Gardenia yellow was also shown to be non-genotoxic using an in vitro comet assay and a micronucleus test with L5178Y cells, although a marginal increase in DNA damage and micronuclei frequency was reported in the respective assays. Additionally, in vivo micronucleus test results clearly demonstrated that oral administration of gardenia yellow did not induce micronuclei formation in the bone marrow cells of male ICR mice. Taken together, our results indicate that gardenia yellow is not mutagenic to bacterial cells, and that it does not cause chromosomal damage in mammalian cells, either in vitro or in vivo.