• Environmental Engineering Research
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• v.20 no.3
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• pp.212-222
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• 2015

Experiments were conducted on the immobilization of eight heavy metals (HMs) (Zn, Cu, Mn, Fe, Ni, Pb, Cd, and Cr) during 20-day rotary drum composting of water hyacinth. The Tessier sequential extraction procedure was used to investigate the fractionation of HMs. The eco-toxicity risk of HMs was assessed by risk assessment code (RAC). In the results, the bioavailability factor (BAF) for different HMs presented in the following order: Mn > Zn = Fe > Cu > Cr > Cd = Pb > Ni. The total concentration of Pb was higher than that of Zn, Cu, Mn, Cd and Cr; however, its BAF was the lowest among these HMs. These results confirmed that the eco-toxicity of HMs depends on bioavailable fractions rather than on the total concentration. The greatest reduction in bioavailability and eco-toxicity risk of HMs occurred in lime 1% and 2% as compared to control and lime 3%. The eco-toxicity risk of Fe, Ni, Pb, Cd and Cr was reduced from low risk to zero risk by rotary drum composting. These studies demonstrated the high efficiency of the rotary drum for degrading compost materials and for reducing the bioavailability and eco-toxicity risk of HMs during the composting process.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.175-176
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• 2011

Applying previous studies performed in the moisture transportation characteristics and shrinkage of lightweight concrete application of shrinkage reduction is to discuss. Applicability of shrinkage reduction effect of lightweight concrete applies for the analysis of PSC girder bridge beam placed on the construction site. Stress of the concrete bridge deck, rebar quantity is calculated by effective elastic modulus method and crack risk is assessed by moisture transport and differential shrinkage analysis. After approximately 10 days maximum tensile stress occurs 6MPa, similar to the case of normal concrete, a maximum tensile stress occurs 3MPa in lightweight concrete and comparing to normal concrete stress was reduced to approximately 50%. Normal and lightweight concrete crack index, respectively, is reduced 1.6 to 1.2, 1.2 to 0.9 in surface and boundary region. Therefore, reduction in shrinkage of concrete were able to confirm reduction of crack risk.

• Nutrition Research and Practice
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• v.4 no.4
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• pp.303-310
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• 2010

Consumption of vegetables and fruits is associated with a reduced risk of stroke, but it is unclear whether their protective effects are due to antioxidant vitamins or folate and metabolically related B vitamins. The purpose of the study was to test the hypothesis that intake of fruits and vegetables, which are major sources of antioxidant and vitamin B complex vitamins, reduces the risk of stroke. Cases consisted of patients diagnosed with first event of stroke (n = 69). Controls (n = 69) were age-, sex-, and body mass index-matched to cases. Multivariable-adjusted regression analysis showed that subjects who ate four to six servings of vegetable per day had a 32% reduction in the risk of stroke, and those with more than six servings per day had a reduction of 69% after adjusting for age, sex, BMI, and family history of stroke. Intakes of total fat, plant fat, calcium, potassium, vitamin $B_1$, vitamin $B_2$, vitamin $B_6$, niacin, and folate were significantly and negatively associated with the risk of stroke. Although the trend was not significant, stroke risk was reduced in the second quartile (1.21-2.66 servings per week) of fish intake. However, intake of fruits (average daily intake of 1.0 serving) and antioxidant vitamins such as carotene, vitamin C, and vitamin E was not associated with the risk of stroke. In conclusion, our observational study suggests that intake of fat and vegetables, rich sources of vitamin B complex, calcium, and potassium may protect against stroke.

• Journal of the Korean Society of Safety
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• v.33 no.2
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• pp.14-20
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• 2018

In this study, we analyze the current status of major disasters in distribution works and propose safety measures through the distribution live-line work method and electric shock risk assessment. The result of analyzing the ratio of electric shocks to the occurrence of industrial accidents in the recent 13 years shows that the death rate is higher than other industries, especially the construction industry occupying most of the disaster, and it is higher than the collapse disaster. We analyze statistic data of 101 victims selected as core words of live work, distribution line, pole and 22.9 kV in the investigation report of major accident of electric shock fatal from 2001 to 2014. The safety measure was established through the risk assessment of the distribution method using the standard model of the risk assessment based on the results of electric shock analysis on the distribution line. In order to prevent the electric shock accident which is recently being discussed, the risk assessment procedure were carried out in the above-mentioned 22.9kV special high voltage live-line operation method. We derived the risk reduction plan for the distribution line from the results of the major accidents statistic and demonstration of the line works.

• Fire Science and Engineering
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• v.10 no.2
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• pp.20-27
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• 1996

This paper discussed the limit of existing safety controls where the use of land around hazardous industry. There is a gap between engineering evaluation of acceptable criteria for loss reduction and risk exposure to the areas of high risk outside plants from the aspects of risk perception. The paper performed how land use safety could be designed between the density of uses with the duration of risk exposure by type of land use. It concluded the needs of multi-dimensional presentation for an appropriate risk controls on existing and future land use safety.

• Journal of radiological science and technology
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• v.47 no.4
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• pp.287-294
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• 2024

Radiation oncology departments are at high risk for potential radiation safety incidents. This study aimed to identify risk factors for these incidents using the P-mSHEL (Patient, Management, Software, Hardware, Environment, and Liveware) model and to evaluate potential accident types through Failure Mode and Effects Analysis (FMEA). FMEA identified seven accident types with high Risk Priority Number (RPN). A total of 56 detailed risk factors were classified using the P-mSHEL model, and measures to prevent radiation safety incidents were implemented. The effect of these preventive measures on workers' safety perception was confirmed through two indicators (FMEA and safety perception). After implementing the preventive measures, the FMEA analysis showed that the highest reduction in RPN was for A-6 (radiation exposure while other patients/guardians are present) with a reduction rate of 33.3%, followed by B-3 (radiation exposure while staff are present) with a reduction rate of 33.3%. Overall safety perception significantly improved after the preventive measures (4.17±0.35) compared to before (2.76±0.33) (p<0.05), with notable increases in both employee safety culture (3.93±0.51) and patient safety culture (3.73±0.62) (p<0.05). This study identified risk factors in radiation oncology departments. Continuous management, maintenance, and fostering a strong safety culture are crucial for preventing incidents. Regular problem identification and collaboration with relevant departments are essential for maintaining safety standards.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.1
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• pp.30-36
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• 2014

There are many treatment options in management of mandibular condylar neck fractures. Closed reduction is the most conservative treatment; however, achievement of anatomic reduction is difficult, and there are some risks of mandibular functional impairment. Open anatomic reduction and internal fixation have some advantages; therefore, many oral and maxillofacial surgeons have attempted to achieve anatomic reduction through the open approach and extracorporeal reduction and fixation. However, when using this method, there is some risk of resorption of the fractured mandibular condylar head. Therefore, we designed a modified extracorporeal reduction technique, without detaching the lateral pterygoid muscle in order to maintain the blood supply to the fractured mandibular condylar head. We believe that this minor modification may minimize the risk of resorption of the fractured mandibular condylar head. In this article, we introduce this technique in detail, and report on two cases.

• Journal of Korean Academy of Nursing
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• v.34 no.6
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• pp.1129-1142
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• 2004

Purpose: This research was conducted to evaluate the effects of asystemic follow-up care program on health promotion and risk reduction in 64 high-risk infants(HRI) including premature infants and their mothers. Method: The intervention consisted of systemic NICU education, tele-counseling and 3 home visits in 6 months. The subjects were divided into either the intervention group or the control group receiving the conventional NICU education without the tele-counseling and home visiting. Infant health promotion was measured using physical assessment, types of health problems, reflexes, OPD visiting history, DDST, immunization, feeding assessment, Infant death rate, etc. Maternal self-esteem, postpartum depression and family function were measured using the maternal self-report inventory(MRI), EPDS, and family apgar score(Fapgar), retrospectively. Result: All premature infants in the intervention group were in the normal range of growth and development, and the regular vaccination schedule. The health problems in the intervention group were addressed early so not to develop into adverse effects. The follow-up program for 6 months showed beneficial effects on MRI, EPDS, and Fapgar. Conclusion: A systemic follow-up health care program is beneficial on health promotion and risk reduction in 64 HRI including premature infants and their mothers.

• Journal of Environmental Health Sciences
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• v.42 no.5
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• pp.345-351
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• 2016

Objectives: The objective of this study was to conduct risk assessment using indoor radon concentration and exposure times. Methods: The target facilities were military facilities before and after the application of radon reduction processes and underground commercial facilities in major subway stations in Seoul. Indoor radon concentrations were measured by passive sampler. Results: Radon concentrations in 13 military facilities were initially higher than the guidelines, but the levels were below guidelines after the application of radon reduction processes. Underground shopping mall radon concentrations near subway stations in Seoul satisfied the guidelines. However, indoor radon effective doses after radon reduction processes in some military facilities and those in underground shopping malls belonged to International Commission on Radiological Protection (ICRP) groups needing control management. Conclusion: Indoor radon management requires risk assessment data that takes into account working time (or residence time) in addition to management according to concentration guidelines.

• Progress in Medical Physics
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• v.26 no.4
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• pp.267-272
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• 2015

In this study, the reduction of dose and risk was evaluated from using automatic mA control in 4D CT scan of patients whose organ movement was considered for gated radiotherapy. The organ doses, CTDI, effective doses from 4D CT with and without using automatic mA control were evaluated using CT-Expo program for each 10 patients of liver and lung cancer, and the risk of exposure induced death and loss of life expectancy were evaluated using PCXMC program. It was founded that there were 26.8%, and 15.5% dose reduction in organ doses and CTDI for liver and lung cancer patients and 16.5% and 19.8% risk reduction in liver and lung cancer patients. The organ doses and effective doses were evaluated for the parameter of each patient used in CT scans, and risks considering age and gender could be evaluated. It was founded that there were 21.2% dose reduction and 18.2% risk reduction in 4D CT scan using AEC for liver and lung cancer patients.