• 한국산업보건학회지
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• 제15권3호
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• pp.153-159
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• 2005

The purpose of this study was to assess the ergonomic risks of lifting tasks in a marine diesel engine manufacturing industry using the National Institute for Occupational Safety and Health(NIOSH) Revised Lifting Equation(NLE). Average Lifting Index(LI=Weight of Load/Recommended Weight Limit) of a total number of 45 lifting tasks was $1.6{\pm}0.7$. The LIs were above 1 at 34 tasks(75.6%), and above 2 at 11 tasks(24.4%). Parts management showed the highest average LI value (LI=2.3) in all departments, which resulted from high frequency and heave load of lifting. The common and significant ergonomic risk factors in the processes were the heavy weight of diesel engine parts and the long horizontal distance. In addition, some lifting tasks had such potential risk factors as the long vertical distance, the high frequency of lifts or the long work duration.

• 한국지반환경공학회 논문집
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• 제10권4호
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• pp.33-40
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• 2009

성토 시공시, 경제적인 시공을 위해 절 성토량의 균형은 중요하게 고려되어야 할 사항이다. 그러나 실제 완성기면까지 성토시 성토체 자체의 압축침하와 연약지반 성토시 발생하는 제체하부 원지반의 압밀침하, 암 버럭 사이의 간극 메움에 의한 침하와 강우와 유출시 발생하는 토량 손실에 의한 성토량의 부족분이 발생하고 있다. 성토량의 부족분에 대한 지침은 도로공사 시방서에 토량환산계수를 통해 설계하도록 되어 있지만 성토체 자체의 압축침하에 의한 부족분은 고려되고 있지 않다. 따라서 본 연구에서는 이세전(伊勢田)(1972)와 석정(石井)(1976)가 제안하고 있는 성토체의 제체압축침하량 산정기법을 적용하여 국내 여러 현장의 성토체를 대상으로 발생가능한 압축침하량을 산정하였다. 본 연구결과 성토고 및 성토재의 종류에 따라 성토고의 약 3~10%내외의 전침하량이 발생하는 것으로 나타났다. 그러므로 실제 설계시 성토재의 특성 및 성토고를 고려한 성토체의 즉시침하 및 크리프 침하를 반영한 설계가 필요할 것으로 판단된다.

• 한국환경과학회지
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• 제7권4호
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• pp.559-564
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• 1998

The effects of temperature, initial $Pb^{2+}$concentration and initial sludge concentration on the initial $Pb^{2+}$ removal rate and maximal $Pb^{2+}$removal amounts in activated sludge, respectively, were investigated. The removal of $Pb^{2+}$ in activated sludge was proved to be temperature-dependent process. The initial $Pb^{2+}$ removal rate increased from 187.5 to 261.4 mg $Pb^{2+}$/g sludge dry weight min, in response to the promoted temperature from 1$0^{\circ}C$ to 6$0^{\circ}C$, while the maximal $Pb^{2+}$removal amount (78.5 mg $Pb^{2+}$/g sludge dry weight) occurred at 30t . As the initial $Pb^{2+}$concentration increased from 36 to 228 mg $Pb^{2+}$/L at the constant temperature of 30C and initial sludge concentration of 1.5 g sludge dry weight/L, the time to reach an equilibrium state was almost independent of the initial $Pb^{2+}$concentration and the equilibrium $Pb^{2+}$/removal amount was increased Irom 41.9 to 73.6 mg $Pb^{2+}$/g sludge dry weight. On the contrary, the equilbrium $Pb^{2+}$ emoval amount was decreased from 87.7 to 65.3 mg $Pb^{2+}$/g sludge dry weight as the in- crease of initial sludge concentration from 0.22 to 1.76 g sludge dry weight/L.

• Asian-Australasian Journal of Animal Sciences
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• 제11권2호
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• pp.152-154
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• 1998

The data 1241 birth, weights of Teddy goats maintained at Livestock Production Research Institute, Bahadurnagar, Okara, Pakistan, during 1975-1990 were used for this study. The mean birth weight during study period ranged from $1.55{\pm}0.06$ to $1.78{\pm}0.09kg$ with and over all mean of $1.66{\pm}0.031kg$. It was found that year of birth, type of birth, sex of kid and age of dam had significant (p < 0.01) effects on birth weight while the effect of season was found to be non-significant. It was inferred that single born kids were significantly heavier than twins and twins were heavier than triplets. The mean values of birth weight for male and female kids were $1.70{\pm}0.032$ and $1.61{\pm}0.03kg$ respectively. The birth weight was found to be the highest in 8 year age group that was $1.82{\pm}0.016kg$ and the lowest in one year group $(1.55{\pm}0.02kg)$.

• 비만대사연구학술지
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• 제3권1호
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• pp.27-34
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• 2024

The prevalence of obesity in children and adolescents is increasing worldwide. Obesity in children and adolescents not only increases the risk of transitioning to obesity in adulthood but also increases the risk of cardiometabolic diseases such as high blood glucose, high blood pressure, dyslipidemia, fatty liver, and hyperinsulinemia during childhood. The goal of treating obesity in children and adolescents is not to focus on weight loss but to help children reach a healthy weight while maintaining normal growth appropriate for their age and sex. To achieve this goal, regular physical activity and exercise, dietary modification, improvement of obesity-prone environmental factors, and behavioral changes are required for a healthy lifestyle. If appropriate weight control is not achieved through lifestyle modifications, pharmacotherapy may be considered for adolescents with severe obesity aged 12 and above. Recent clinical trials have reported the efficacy and safety of pharmacotherapy in severely obese adolescents. Currently, two medications can be prescribed in Korea for patients with obesity aged 12 and above: Orlistat and Liraglutide. However, despite effective weight control through drug treatment, body weight may increase again after treatment discontinuation. Therefore, it is crucial to evaluate adherence to health behaviors during visits and continue to educate on lifestyle modifications, even during pharmacotherapy, to minimize weight regain.

• 동아시아식생활학회지
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• 제4권3호
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• pp.21-30
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• 1994

The relationship between bone mineral density and the environmental factors were investigated from the view point of preventing osteoporosis in Korean pubescent girls. The effects of calcium, nutrient intake, physical activity on total bone mineral density, lumbar spine and femoral bone mineral density and total bone mineral content were evaluated 33 healthy pubescent girls aged 14∼16y. A convenient method was used to assess nutritional and energy intake and calcium index was used together. Calcium intake in childhood was estimated by asking whether subjects usually drank milk as children. Eating habits data and history of menstruation were obtained by questionnaire and interview. Average energy expenditure was calculated. Bone mineral density and content were measured by dual energy x-ray absorptiometry using a Lunar DPX＋Scanner (Lunar, Madison, WI). The lumbar spine(L2∼L4) and three sites in the proximal femur (femoral neck, trochanteric region, and Ward's triangle)were measured. Height and weight were measured, and the body mass index(BMI) was derived from the formula : BMI=kg/㎡ Statistical analysis was performed by simple correlation using the SAS package. The mean calcium intake (736mg) was below the RDA of 800mg/d. Twelve percent of the total subjects did not drink milk at all because they did not like the taste. Skipping meals, low calcium intake and low energy intake were significantly correlated with the low BMD. Also the data indicate that girls who reported drinking milk with every meal during childhood had significantly higher bone densities than girls who reported drinking milk less frequently. The results suggest that milk consumption in childhood appears to be needed not only for growth and development, but possibly also to assure an optimal peak of bone mass and thus greater latitude for the maintenance or skeletal integrity in the face of bone losses. There was a highly significant correlation between the total BMD and overall level of physical activity. Body weight was a better predictor of total BMD than was and other factor. Simple mechanical loading may explain why body weight, but total BMC was positively relatd to height. Conclusively, increasing calcium intake and physical activity in the pubescent girls could influence BMD.

• 한국의류학회지
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• 제39권6호
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• pp.812-825
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• 2015

This study explored various issues related to the quality-of-life for obese Korean men. In-depth interviews were conducted with thirty men over BMI 25 whose age ranged from 20's to 50's. Projective techniques along with semi-structured interviews were used. The results of interviews were analyzed based on grounded theory. "Stress" was the main phenomenon resulting from the causal conditions of obesity and stigma. Stress consisted of social, psychological, physical and environmental factors. Contextual conditions mediating the relationship between causal conditions and main phenomenon were obesity level, pressure, and public appearance. Avoidance, change of personal traits, and insensitivity were the action/reactions to the main phenomenon. Various factors due to obesity disappeared and quality-of-life increased when they succeed in weight reduction; however, factors related to obesity and lowered condition of quality-of-life continued if they experienced a weight gain/loss yo-yo.

• Asian-Australasian Journal of Animal Sciences
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• 제25권1호
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• pp.22-27
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• 2012

The experiment involved observations of 2,514 Holstein-Friesian cows to determine the effects of environmental factors (cow's age, calving season, weight and sex of calves, housing system) and genetic factors on gestation length in dairy cattle and the correlation between gestation length and other reproductive traits (calving ease, stillbirth rates and placental expulsion). Genetic parameters were estimated based on the sires of calved cows (indirect effect) and the sires of live-born calves (direct effect). The following factors were found to contribute to prolonged gestation: increasing cow's age, male fetuses and growing fetus weight. Optimal gestation length was determined in the range of 275-277 days based on calving ease and stillbirth rates. The heritability of gestation length was estimated at 0.201-0.210 by the direct effect and 0.055-0.073 by the indirect effect. The resulting genetic correlations suggest that the efforts to optimize (prolong) gestation length could exert an adverse influence on the breeding value of bulls by increasing perinatal mortality and calving difficulty. The standard errors of the investigated parameters were relatively high, suggesting that any attempts to modify gestation length for the purpose of improving calving ease and reducing stillbirth rates should be introduced with great caution.

• Plant Resources
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• 제6권2호
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• pp.94-97
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• 2003

The objective of this study is to investigate morphological characteristics of seeds and effects of environmental factors such as light and temperature on the germination and seedling growth of Adenophora triphylla var. japonica, Codonopsis lanceolata, Platycodon glandiflorum, Which belongs to Campanulaceae and useful for on oriental medicine materials. Seed shape of Codonopsis lanceolata is Elliptic. Platycodon glandiflorum is Oblong. Color of seed coats varied from yellow to dark brown. Seed size of Adenophora triphylla var. japonica is 1.37mm in length, 0.69mm in width. One thousand-seed weight of Adenophora triphylla var. japonica is 258mg. Seed size of Codonopsis lanceolata is 4.45mm in length, 2.11mm in width. One thousand-seed weight of Codonopsis lanoceolata is 1,278mg. Seed size of Platycodon glandiflorum is 2.31mm in length, 1.10mm in width. One thousand-seed weight of Platycodon glandiflorum is 988mg. Optimum temperatures for seed germination and seedling growth range from 20 to $25^{\circ}C$.

• 한국농공학회논문집
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• 제57권1호
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• pp.99-109
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• 2015

In the construction industry, the interest for recycling aggregates is rising as more people demand for alternatives due to lack of supply of natural aggregates and environmental problems. However, in order for recycled aggregates to be used in infrastructures, stability and other factors need to be verified. Therefore, the objective of this study is to analyze the sensitivity of soil properties to secure slope safety according to various heights of embankment when bottom ash and dredged soil mixture is applied in the embankment. In most cases, all heights were safe for the slide for the embankment whether the water level is full or sudden draw down. The result of the sensitivity analysis revealed that the unit weight of embankments is highest among all factors to be considered. However, the sensitivity of the unit weight became smaller and the sensitivity of the friction angle of embankments increased with the height of embankments. The sensitivity of factors of core materials is very small because the core has weaker physical properties than those of the embankment. The effect of the height for each factor is different for each slope and water levels. The sensitivity of the unit weight of embankments is most affected when the height is 60m in the upstream slope. To conclude, bottom ash and dredged soil mixture can be applied in the embankment and different factors must be considered in different scale because the sensitivity depends highly on the height of embankments.