• Journal of the Korean Geosynthetics Society
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• v.19 no.4
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• pp.33-40
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• 2020

It is now common to find the wastes buried in the past during the excavation process of soil for large scale housing and land development. Without proper treatment of the wastes environmentally, the excavation process is no longer able to proceed, and an action plan should be provided to treat the wastes with environmental and economic viability. In the study, the relationship between the apparent density of the wastes and the volume conversion factor, which is the basis in the estimation of waste treatment cost was investigated. From 10 sampling points of a landfill site, wastes were sampled, analyzed for physical characteristics, and the apparent density of mixed and sorted waste was assessed. Applying the empirical formula, and the formula we suggested here, the volume conversion factors were compared with that measured directly in the field using dump truck and excavator. Obviously there was a close relationship among the volume conversion factors resulting from the empirical formula, the formula we suggested and that measured in the field.

• Journal of Digital Convergence
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• v.19 no.8
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• pp.275-283
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• 2021

This study was intended to help improve assessment in college EFL classes by examining the relationship between formative assessment (FA) and summative assessment (SA). Participants for the study were 75 undergraduates, taking an eight-week optional college English course at a four-year college in China. FA data were collected in the final course of the course by a self-reporting survey using the online training platform Mosoteach. To achieve the finding, the relationship between FA scores and SA scores (final exam and performance scores) was analyzed in SPSS by means of Pearson correlation analyses. Significant positive correlations were found between FA and SA scores overall. In addition, students' performance on chapter tests, online discussions, brainstorming, quick-responses, assignments and the number of thumbs-up clicks by teachers were significantly correlated with SA scores. The results suggested that FA administered through the Mosoteach app could improve students' academic performance, thus providing an empirical basis for improving educational assessment. Based on these findings, implications for assessment in EFL classes were described.

• Solar Energy
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• v.14 no.2
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• pp.17-28
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• 1994

It is necessary to estimate enpirical constants in order to predict the monthly mean daily global radiation on a horizontal surface in the developing areas for alternative energy. Therefore many different equations have propoed to evaluate them for certain areas. In this work a new corrlation has been made to predict the solar radiation for any areas over Korea by cululating the regression models taking into account latitude, percentage of possible sunshine, and cloud cover. From the results, the single linear equation proposed by using percentage of possible sunshine method shows reliable results for estimating the global rdiation with average annual deviation of -4 to +2% from measured values.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.840-848
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• 2007

This study was performed in order to investigate the stress levels, sleep, anthropometric measurement and nutrient intakes their correlations of college students. General characteristics, stress scores using a stress test, sleep scores using a sleep test, anthropometric measurement, body composition using Inbody 3.0 and nutrient intakes using 3-day recalls were measured in 353 subjects (183 males and 170 females). Mean total stress score of the male students was 68.2${\pm}$45.0 and that of the female students was 86.5${\pm}$48.7. Stress for study, future, economic and value-related factors were higher than other factors in both male and female students. Female students were more stressed than male in friend, family, study, future and value-related factors. Mean sleeping time and sleep scores of the male students were 7.0 hrs and 40.6${\pm}$5.7, respectively and that of the female students were 7.1 hrs and 41.5${\pm}$5.3, respectively. Mean height, weight, percent body fat (PBF) and waist-hip ratio (WHR) of the male students were 174.8 cm, 73.3 kg, 19.0% and 0.84, respectively. Mean height, weight, PBF, and WHR of the female students were 161.7 cm, 55.3 kg, 28.7% and 0.81, respectively. Mean energy and protein intakes of the male students were 2026.3 kcal (77.9% EER) and 83.0 g (150.9% RI) and those of the female students were 1538.2 kcal (73.2% EER) and 60.7 g (134.9% RI), respectively. In male students, sleep duration, professor and future problem showed significantly negative correlation (p<0.05). For both male and female students, in correlations between sleep scores, life stress experience frequency and importance, the total scores showed significantly negative correlation (p<0.01). Sleep scores (sleep quality) have more significant correlation than sleep duration in life stress. In male students, correlations between economic problem and weight, waist circumference and hip circumference showed significantly negative correlation. In female students, correlations between different gender problem and body mass index (p<0.05), PBF (p<0.01), WHR (p<0.01) and obesity degree (p<0.05) showed significantly negative correlation while correlation between study problem and PBF (p<0.05), WHR (p<0.05) showed significantly positive correlation. In male students, there were significantly positive correlations between life stress experience frequency and carbohydrate calcium, iron, vitamin A; correlation between importance and calcium, iron as well as correlation between total life stress scores and iron (p<0.05). In female students, correlation between life stress experience frequency and thiamin along with correlation between importance and thiamin showed significant negative correlation (p<0.05). College students need to practice good life habits for the purpose of correctly managing life stress.

• The Korean Journal of Food And Nutrition
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• v.11 no.1
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• pp.87-98
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• 1998

This study was conducted to investigate Osteoporosis on the effect of dietary factors and past young age period's dairy products consumption on BMD in 170 postmenopausal Korean women without diagnosed disease. Bone mineral density(BMD) of lumbar spine was investigated by dual energy X-ray absorptiometry. Dietary assesment of the subjects were measured by Cognitive Food Frequency Recall method. The measurements of group average were 57.9kg of body weight, 36.73 of BMI(Body Mass Index), 2103.3㎉ of energy, 638.7mg of dietary calcium, 70.3g of protein, and 10.58mg of iron. Nutrient intake levels were similar to or more than the level of Korean Recommended Dietary Allowances. Bone Mineral Density(BMD) of Lumbar spine(L2-L4) of group average was 0.912g/$\textrm{cm}^2$, and under 50 yr's 1,02g/$\textrm{cm}^2$, 50~54 yr's 0.92g/$\textrm{cm}^2$, 55~59 yr's 0.85g/$\textrm{cm}^2$, over 60 yr's 0.85g/$\textrm{cm}^2$, had been getting low degree on aging. BMD of the Lumbar spine was positively correlated with calorie, body weight, dietary calcium, protein, phosphorus and serum albumin. Past dairy products consumption experiment was highly significant on BMD in teenage period(R square = 26, p-value 0.0031). Particularly in over 60 yr group, the correlations between BMD and past dairy products consumption in teenage period had shown highly significance(r=0.48, p<0.02). 55~59 yr age group had also positive correlation(R squae = 0.29, p<0.05). This results confirm that the most effective way of preventing osteoporosis and the fractures is to maximize peak bone mass in early life and to minimize bone loss through the balanced intake of Ca and other nutrients and regular physical activity.

• Proceedings of the Korea Contents Association Conference
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• 2016.05a
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• pp.451-452
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• 2016

본 연구는 핵심기본간호술 학습경험과 중요도인식, 학습 자기효능감이 수행자신감에 미치는 영향을 파악하여 핵심기본간호술 수행능력 향상을 위한 학습전략 마련의 기초자료로 활용하고자 D지역 소재 일개대학 간호학과에 재학중인 학생 231명을 대상으로 실시하였다. 본 연구결과 학습경험은 학년에 따라, 학습 자기효능감과 수행자신감은 전공만족도와 실습만족도에 따라 유의한 차이가 있었다. 핵심기본간호술 학습경험과 수행자신감, 학습 자기효능감과 수행자신감에서 긍정적 상관관계, 수행자신감에 영향을 미치는 요인은 학습 자기효능감과 학습경험순으로 나타났다. 따라서 핵심기본간호술 수행자신감을 향상시키기 위한 교육전략 수립 시 학습 자기효능감을 강화시키고, 학습경험을 증가시키는 방안이 필요하다.

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.33-40
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• 2011

The resilient modulus which is presented mechanical properties of compacted subbase material is the design parameter on the Mechanistic - Empirical pavement design guide. The compaction control method on the Mechanistic - Empirical pavement design guide will be the way to confirm whether the in-situ elastic modulus measured after the compaction meets the resilient modulus which is applied the design. The resilient modulus in this study is calculated by the neural network suggested by Korea Pavement Research Program, and degree of compaction as the existing compaction control test and plate bearing capacity test(PBT) was performed to confirm whether the in-situ elastic modulus is measured. The Light Falling Weight Deflectometer(LFWD) is additionally tested for correlation analysis between each in-situ elastic modulus and resilient modulus, and is proposed correlation equation and test interval which can reduced overall testing cost. Also, the subbase compaction control procedure based on the in-situ elastic modulus is proposed using the in-situ PBT and LFWD test result.

• Journal of Korea Water Resources Association
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• v.40 no.10
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• pp.755-768
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• 2007

The purpose of this study is to analyse the characteristics of Manning's roughness coefficient according to change of discharge by using observed data obtained from a stable gravel-bed river and to investigate the applicability of the relevant existing empirical methods to it. Observed water level and discharge data are used as input data for the USGS computer program NCALC model for calculation of the roughness coefficient. Calculated values are compared with roughness values which are estimated with four widely used methods. The results show that though the empirical methods are able to give similar roughness values only for flood flow, they seem to have rather high uncertainty because of necessity of subjective judgement and differences of resultant values. Roughness coefficients for normal-low flow cannot be estimated from the existing empirical formulae. Especially, using the Manning equation for calculating them should be careful as this provides a wide range of estimated values in normal-low flow. The relations between the roughness coefficient and characteristic size of bed materials are different from them in flood flow even though they have a close relations.

• Journal of Chest Surgery
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• v.29 no.9
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• pp.1045-1049
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• 1996

Post-intubation tracheoesophageal fistula is rare, and its management causes a serious problems to surgeons. We have experienced 4 cases in 3 patients. Simple ditcision and closure of the fistulas were done by trans-cervical approach after weaning of ventilator. The tracheal defect was closed by simple suture, and the esophageal defect was closed in two layers before a viable muscle flap was interposed between the two suture lines in order to prevent recurrence. There was one delayed tracheal stenosls and one recurrent fistula, and these complications were also managed success ully.

• Journal of Korea Water Resources Association
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• v.47 no.9
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• pp.743-752
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• 2014

Delay time for groundwater recharge means the travel time from the bottom of soil layer to groundwater through vadose zone after infiltration from rainfall. As it is difficult to measure delay time, we suggested an empirical formula which is derived by using linear regression between altitude and delay time. For the regression analysis, 4 major gauging watersheds were chosen (Hancheon, Kangjeongcheon, Oedocheon, Cheonmicheon) with 18 measured groundwater level stations. To verify this empirical formula, derived equation from linear reservoir theory was applied to compute delay time and to compare estimated amounts of groundwater recharge using both methods. The result showed good agreement. Furthermore, if derived empirical formula would be linked with SWAT model, the spatial time delay effect in the watershed could be reflected properly.