• Design & Manufacturing
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• v.14 no.2
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• pp.49-55
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• 2020

Recently, when a new component of construction equipment is designed, a stamping process capable of producing parts having high appearance quality and precision has been gaining attention. However, in general, as it is developed based on existing parts made by welding metal sheets and tubes, frequent to die modification occurs, which increases the time and cost of developing new parts. Thus, it is necessary to reduce the cost by shortening the die development period. In this study, a stamping process was designed for the urea tank cover, which is a part for excavators, to reduce the die development period through sheet metal forming analysis. The stamping process was designed by determining the blank holding force after selecting the initial blank shape and size. The round value at the corner was modified such that formability is ensured. After selecting process parameters, the thickness reduction rate and spring-back effect were reviewed.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.2
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• pp.310-320
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• 2020

This study established a lower garment sizing system for abdominal obesity adult women aged 30-59 based on 277 females selected from the 7th Size Korean Anthropometric survey. The criteria for subjects in this study were over 25 kg/㎡ of the BMI, over 85 cm of waist, and over 0.8 waist hip ratio. The results are as follows. The lower body analysis of abdominal obesity adult women showed that average circumference items were larger than the ordinary size, and the average length items were smaller. The standard deviation was applied around the average values of waist circumference and hip circumference for the suggestion of a lower garment sizing system for abdominal obesity adult women. The interval between the designation was ±1.5 cm with a waist circumference of 100 cm and ±2.5 cm with an average hip circumference of 100 cm. We established 13 designation sections in consideration of the cover ratio and cover efficiency. The cover ratio in the 13 nominal sections was 71.5%. The segmental distribution rate presented in the results will also be useful for production planning in specific sizes that helped enable rational production.

• Journal of the Korean Society of Safety
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• v.30 no.6
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• pp.102-109
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• 2015

In this study, on the basis of the results of the field survey and the theoretical consideration for Korean Standard Specification for concrete durability and maintenance, the following conclusions are derived. From the survey, the prediction equation of carbonation depth for the southwest region in Korea is experimentally proposed, $y_p=5.865{\sqrt{t}}$, which predicts about 60mm of the carbonation depth for the concrete structures of 100 years, a 1st class of target endurance period, under a combined deterioration environment like a marine environment. Considering that the marginal value for a carbonation depth limitation under very severely marine environment is 25mm, in accordance with the Specification, it is found that the predicting carbonation depth for the concrete cover depths, 100mm and 60mm are 63mm and 29.4mm, respectively. In conclusion, according to the equation and the Specification, it is strongly required that the reinforced concrete structures with the cover depth under 100mm have to make a protection from combined deterioration factors by any methods like a surface coating, an increment of cover depth or an application of a special concrete.

• The Journal of the Korean dental association
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• v.58 no.1
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• pp.38-44
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• 2019

Although the Korea National Health and Nutrition Examination Survey (KNHANES) calculates oral health functional restriction rate and chewing discomfort rate every year, these two indicators are not all indicators of oral health. Therefore, indicators are needed to subdivide by age group and cover dental caries, periodontal disease, remaining teeth, and oral care use. The purpose of this study is to identify the key indicators of oral health in mature and middle age. The average number of existing natural teeth, the rates of 20 or more natural teeth, complaints of chewing discomfort, oral examination, periodontal disease and dental caries, were analyzed using KNHANES VI (2013-2015) as a complex sample. In the age group between 40 and 64, there were 25.2 natural teeth remaining, 91.4% natural teeth retention rate, 23% chewing discomfort rate, 34.7% oral examination rate, 38.7% periodontal disease prevalence, 6.46 the number of caries experience teeth, 21.4% interdental brush usage rate.

• Weed & Turfgrass Science
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• v.3 no.4
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• pp.318-322
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• 2014

The effects of cover crops on weed suppression were evaluated in this study. Weed suppressing effects of hairy vetch cover crops were evaluated in summer grain fields. Cover crops were sown at the sowing rate of $60kg\;ha^{-1}$ on Oct. 2012 and Feb. 2013 without basal fertilization. Three weeks old sorghum seedlings were transplanted after minimum tillage on June 2013. Hairy vetch cover crop treatment significantly reduced weed biomass in the transplanted sorghum. By smothering, the cover crops reduced weed biomass to economic level in sorghum. Besides the weed suppression, hairy vetch cover crop resulted in green manure effect on crop growth. Hairy vetch treatment showed beneficial effects on sorghum growth. Reduction of weeds caused by use of strip-tillage machine and polyethylene film mulching was 71% and 88%, respectively. At harvest, yield of sorghum was greater in order of polyethylene film mulching > hairy vetch cover crop > control in transplanted fields.

• Weed & Turfgrass Science
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• v.6 no.1
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• pp.55-60
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• 2017

Shade affects turf quality by reducing light for photosynthesis. The shade tolerance of the tropical grasses, Digitaria longiflora and Axonopus compressus were evaluated against Stenotaphrum secundatum (St. Augustinegrass). The grasses were established under shade structures that provide 0%, 50%, 75% or 90% shade level for 30 days. A suite of leaf traits, recorded from similar leaf developmental stage, displayed distinct responses to shade conditions. Leaf length, relative to control, increased in all three species as shade level increased. The mean leaf extension rate was lowest in St. Augustinegrass (80.42%) followed by A. compressus (84.62%) and D. longiflora (90.78%). The higher leaf extension rate in D. longiflora implied its poor shade tolerance. Specific leaf area (SLA) increased in all species with highest mean SLA increase in D. longiflora ($348.55cm^2mg^{-1}$)followed by A. compressus ($286.88cm^2mg^{-1}$) and St. Augustinegrass ($276.28cm^2mg^{-1}$). The highest SLA increase in D. longiflora suggested its lowest performance under shade. The percent green cover, as estimated by digital image analysis, was lowest in D. longiflora (53%) under 90% shade level compared to both species. The relative shade tolerance of the three turfgrasses could be ranked as St. Augustinegrass > A. compressus > D. longiflora.

• Journal of Korean Biological Nursing Science
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• v.17 no.4
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• pp.348-355
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• 2015

Purpose: This survey aimed to identify cough etiquette knowledge and practice level among university students. Methods: 190 study subject were recruited from a university located in C city of Korea and data were collected utilizing self-reported questionnaires to evaluate cough etiquette knowledge and practice levels. Results: The score of cough etiquette knowledge was 7.38 out of 12 and the correct answer rate was 61.5%. The respondents showed the highest right answer rate (85.3%) on 'cover with a paper tissue or a handkerchief while coughing' and lowest (20.7%) on 'cover with hand while coughing'. Practice level score was 27.28 out of 48. Among those items of practice, 'wearing a mask while coughing' was the lowest (1.40/48) level of practice. And the correlation between knowledge and practice was not significant. Conclusion: Cough etiquette knowledge and practice level was revealed to be rather low among university students. Education and social marketing are needed to be developed to encourage the practice level of cough etiquette followed by better droplet infection control and health promotion.

• Human Ecology Research
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• v.58 no.2
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• pp.215-228
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• 2020

Underlying dress forms for high coverage patterns are very important in the dress industry. Size 9 from brand D was chosen according to the analysis that it was the best option because a dress should have a large allowable range in one size. The criteria for selection were the dress form with a waist circumference of 63.50 centimeters, which is close to the standard size of women in Korea. Brassieres for dresses were included to enhance the aesthetic value of the correction process in producing a basic dress pattern. An experimental torso pattern was applied to evaluate the fit and suitability of the dress form that was also later verified in the process of the dress works. Three dresses were produced and presented on the chosen study dress form. The research procedures are as follows. First, the sell-through rates and feedbacks were collected from the dress form vendor. Second, a literature survey on dresses and a dress company investigation were conducted. Third, the amount of body dimension changes due to the use of a bra in the dresses were examined. Fourth, after the correction of the dress form, the torso pattern was made by draping. Fifth, the torso experimental clothing made of muslin material was evaluated. Sixth, the dress works of the top design were presented using the size 9 basic pattern developed by brand D.

• Magazine of the Korean Society of Agricultural Engineers
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• v.38 no.2
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• pp.123-132
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• 1996

The purpose of this study was to clarify the reflectance of soil and plant in order to extract the soil and vegetation informations using the satellite remote sensing data. The influence of soil moisture content and vegetation cover rate on the soil reflectance, and the relationship between vegetation reflectence and its vitality were discussed. The results obtained in this study were summarized as follows; I) The soil reflectance($R_{0.65}$) of wavelength ($0.65{\mu}m$) was closely related to the reflectance((($IR_{0.85}$) of wavelength $0.85{\mu}m$. This relationship could be expressed by soil line. 2) A point on the soil line was affected by the soil moisture ratio and the organic matter content. 3) The vegetation cover rate was formulated in terms of soil and vegetation reflectance at wavelengths pf $0.65{\mu}m$($R_{0.65}$) and ($0.85{\mu}m$) (($IR_{0.85}$). 4) The vegetation reflectence was strongly influenced by its vitality, which was related to the moisture content and the chlorophy [[-a concentration.

• Advances in nano research
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• v.12 no.3
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• pp.319-336
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• 2022

Evaluating the temporal and spatial changes in the ecosystem service value (ESV) of the Sanjiangyuan Nature Reserve is important for understanding the impact of human activities on natural ecosystem and guiding ecosystem restoration and environmental pollution control. In this study, remotely sensed land-cover data and the equivalent factor method were used to analyze the spatiotemporal evolution characteristics of the ESV in Sanjiangyuan Nature Reserve from 1992 to 2015, and regression analysis was employed to determine the factors driving changes in the ESV. The results show that grassland was the main type of ecosystem in the study area, and the transformation of grassland into bare areas was the primary change in land cover. Additionally, the ESV in the study area first decreased and then increased, with an annual growth rate of 0.69%. The ESV mainly increased in the north of the Yellow River's source area, and mainly decreased in the northwest of the Yangtze River's source area. Finally, the gross output value of agriculture, urbanization rate and proportion of secondary industry were found to be the main factors driving the ESV in the study area.