• Current Photovoltaic Research
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• 제2권2호
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• pp.59-62
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• 2014

Minority carrier diffusion length is one of the most important parameters of solar cells, especially for short circuit current density (Jsc). In this report, we proposed the calculating method of the minority carrier diffusion length ($L_n$) in CIGS solar cells through biased quantum efficiency (QE). To verify this method's reliability, we chose two CIGS samples which have different grain size and calculated $L_n$ for each sample. First of all, we calculated out that $L_n$ was 56nm and 97nm for small and large grain sized-cell through this method, respectively. Second, we found out the large grain sized-cell has about 7 times lower defect density than the small grain sized-cell using drive level capacitance profiling (DLCP) method. Consequently, we confirmed that $L_n$ was mainly affected by the micro-structure and defect density of CIGS layer, and could explain the cause of Jsc difference between two samples having same band gap.

• 한국작물학회지
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• 제45권4호
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• pp.245-250
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• 2000

This study was conducted to analyze the responses of some agronomic traits to the different cultural environments and relations among the agronomic traits for selecting sesame varieties with higher cultural stabilities. The indexes for stability parameters measured were coefficient of variability, heritabilities, genetic correlations and path coefficients of agronomic traits according to locations and years in Korea. The heritabilities of agronomic traits showed different by locations and years. Number of seeds per capsule and 1000 seeds weight showed higher heritabilities, but stem length and seed weight per plant showed relatively lower heritabilities. Average heritabilities of some agronomic traits in 1998 were comparatively higher than those of 1999. Of six areas, Jinju area showed biggest coefficient of yield variability in 1998-1999. Iksan and Taegu areas showed higher heritabilities in 1998, but Iksan and Jinju areas showed lower heritabilities in 1999. Genetic correlations were slightly higher than corresponding phenotypic correlations. Stem length showed positive genetic correlation with the number of capsules per plant, and seed weight per plant and the number of capsule per plant showed positive genetic correlation with seed weight per plant. On the analysis of path coefficients, stem length and number of capsules effected highly on grain yield. Great regional variations were observed on the effects of agronomic traits on grain yield. Higher direct effects of stem length on grain yield were observed at Suwon, Chungwon, Taegu, Jinju and Naju areas, but in Iksan area was observed higher direct effect of the number of capsules per plant on grain yield in 1998. In 1999, higher direct effect of stem length on grain yield was observed at Chungwon and Suwon areas. Iksan and Taegu areas were also observed higher direct effect of the number of capsule per plant on grain yield.

• Clinical and Experimental Pediatrics
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• 제63권9호
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• pp.361-367
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• 2020

Background: Length of stay is a significant indicator of care effectiveness and hospital performance. Owing to the limited number of healthcare centers and facilities, it is important to optimize length of stay and associated factors. Purpose: The present study aimed to investigate factors associated with neonatal length of stay in the neonatal intensive care unit (NICU) using parametric and semiparametric models and compare model fitness according to Akaike information criterion (AIC) between 2016 and 2018. Methods: This retrospective cohort study reviewed 600 medical records of infants admitted to the NICU of Bandar Abbas Hospital. Samples were identified using census sampling. Factors associated with NICU length of stay were investigated based on semiparametric Cox model and 4 parametric models including Weibull, exponential, log-logistic, and log-normal to determine the best fitted model. The data analysis was conducted using R software. The significance level was set at 0.05. Results: The study findings suggest that breastfeeding, phototherapy, acute renal failure, presence of mechanical ventilation, and availability of central venous catheter were commonly identified as factors associated with NICU length of stay in all 5 models (P<0.05). Parametric models showed better fitness than the Cox model in this study. Conclusion: Breastfeeding and availability of central venous catheter had protective effects against length of stay, whereas phototherapy, acute renal failure, and mechanical ventilation increased length of stay in NICU. Therefore, the identification of factors associated with NICU length of stay can help establish effective interventions aimed at decreasing the length of stay among infants.

• 한국물환경학회지
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• 제24권5호
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• pp.569-580
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• 2008

In this study, area-weighted slope and slope length module, considering measured field slope and slope length of the agricultural fields within the subwatershed, was developed using the ArcView Avenue programming to reflect the field topography of the Soil and Water Assessment Tool (SWAT) HRU in simulating the hydrology and water quality. Flow and sediment yield estimated values of the SWAT were compared with and without applying area-weighted slope and slope length module, developed in this study. There was 103% increases in estimated sediment with area-weighted slope and slope length module for the study watershed. The soil erosion and sediment yield from only agricultural field in Hae-an watershed was also assessed. There are 111% increase in estimated soil erosion and 112% increase in estimated sediment by applying area-weighted slope and slope length module. This study shows that the area-weighted slope and slope length module needs to be utilized in estimating the HRU field slope and slope length for accurate estimation of soil erosion and nonponit source pollutant modeling with the SWAT although it is not feasible to measure topographic information for every agricultural fields within the watershed. The area-weighted slope and slope length module can be used in identifying soil erosion hot spot areas for developing cost effective and efficient soil erosion management practices.

• 한국구조물진단유지관리공학회 논문집
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• 제19권5호
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• pp.75-82
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• 2015

본 연구는 고강도 철근을 확대머리 이형철근으로 사용하는 경우 정착길이 효과에 관한 실험 연구이다. 현행 기준에서는 확대머리 이형철근의 정착길이를 산정하는 식에서 철근의 설계기준강도를 400 MPa로 한정하고 있다. 고강도 철근에 대한 연구결과가 충분하지 않기 때문에 이러한 규정이 명시된 것이다. 따라서 본 연구에서는 설계기준 항목강도 600 MPa의 철근으로 확대머리 이형철근을 제작하여, 변수별 실험연구를 수행하였다. 실험은 철근의 정착길이, 철근의 개수, 그리고 확대머리의 형상 등의 변수로 계획하였다. 실험체는 정착길이가 긴 L형과 정착길이가 짧은 S형으로 분류하고, 확대머리의 형상은 원판형(A형)과 원뿔형(B형)으로 구분하였다. L형 실험체는 원판형 확대머리를 대상으로 철근 개수가 1~3으로 변하는 3개의 실험체와 S형 실험체는 원판과 원뿔형 확대머리 형상에 대하여 정착길이를 L형의 50%, 45%, 40%, 35%로 변화한 실험체를 계획하였다. L형(LA형) 3개, SA형 4개, SB형 4개 등 총 11개의 실험체를 인발실험을 하였다. 실험결과는 콘크리트구조기준(부록 II)의 정착길이 산정 규정에 따라 평가하였으며, 그 결과 항복강도 600 MPa의 철근을 사용한 확대머리 이형철근은 현행기준의 설계식을 적용하여 설계할 수 있음을 보였다.

• 대한치과보철학회지
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• 제34권4호
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• pp.755-779
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• 1996

This study was designed to development of stock tray for Korean. The subjects for this study were 374 persons(male : 204, female : 170) with age $19{\sim}28$. The study models were made with irreversible hydrocolloid impression material and conventional stock tray, Individual trays were made on the study model and the master models were made after impression with polysulfide rubber impression material. Each of the master models measured 12 measuring points on the maxillary model and 13 measuring points on the mandibular model with digital sliding caliper. The values were analyzed statistically by SAS analysis. The measuring points were analysed and were consulted for the development of new stock tray for Korean. Maxillary models were divided into four groups acceding to the width between buccal alveolar ridges below the contact point of first molar and second molar. The size of new tray of the upper first group was 82mm (width), 60mm(length). That of the upper second group was 77mm (width), 59mm (length). That of the upper third group was 72mm (width), 58mm (length). And that of the upper fourth group was 67mm (width), 57mm (length). Mandibular models were devided into three group according to the width between lingual alveolar ridges below the second molar. The size of new tray on lower first group was 40mm (width), 55mm (length). That of the lower second group was 36mm (width), 55mm (length). And that of the third group was 32mm (width), 55mm (length). The author tested the fitness of newly designed stock tray in 52 subjects with normal occlusion and obtained good results that the problems of conventional stock tray were worked out.

• 한국환경농학회지
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• 제42권4호
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• pp.297-310
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• 2023

M.7 rootstock is moderately resistant to fire blight. However, M.7 is generally too vigorous for high-density apple systems, but it can be grafted onto cultivars that exhibit weak tree growth, such as 'Sansa'. This study investigated the vegetative growth, yield, and fruit quality of 'Sansa' apple trees grafted on M.7 or M.9 rootstocks to assess the feasibility of establishing domestic high-density apple systems using M.7 and to determine the optimum exposure length for rootstocks. Trees were planted with exposed rootstock lengths of 5, 10, and 15 cm. The vegetative growth of apple trees grafted onto M.7 was greater than that of M.9 and vegetative growth tended to decrease as the exposed length of rootstock increased. However, the differences in yield per tree, average weights, soluble solids contents, and titratable acidity due to the rootstock and its exposure length varied. The accumulated yield over a 10 year period and the yield efficiency of M.7 were lower than that of M.9 and the yield efficiency tended to decrease as the exposed length of rootstock increased. When apple trees were grafted onto M.9, biennial bearing and tree vigor weakening occurred if the exposed length of the rootstock was over 10 cm. Conversely, when apple trees were grafted onto M.7, vegetative growth was excessive if the exposed length of rootstock was below 10 cm. Based on the results from this study, the optimum M.7 and M.9 exposure lengths for 'Sansa' were 15 cm and 5 cm, respectively.

• 한국구조물진단유지관리공학회 논문집
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• 제13권1호통권53호
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• pp.186-194
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• 2009

본 연구는 저자가 수행하고 있는 FRP로 보강된 콘크리트 보의 거동연구에 관한 일련의 연구 중 일부로서 본 연구에서는 인장보강근이 겹이음된 콘크리트보의 휨거동에 대한 실험적 연구결과를 제시하였다. 실험변수로는 보강근의 직경과 보강근의 겹이음길이를 적용되었으며, 총 14개의 겹이음된 실험체와 4개의 겹이음되지 않은 기준실험체에 대한 휨실험을 실시하여 각 실험변수인 보강근의 직경(10, 13, 16, 19mm)과 겹이음길이(0.72부터 1.58ld)에 대한 실험결과를 정리하였다. 각 보강근의 겹이음길이는 ACI 440에서 제시하고 있는 FRP 보강근에 대한 기준을 적용하였으며, 실험결과에서 사용된 FRP 보강근의 경우, 기준에서 제시하고 있는 부착길이에 대한 1.3과 1.6의 계수가 충분한 것으로 나타났다.

• 한국수산과학회지
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• 제40권6호
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• pp.380-386
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• 2007

Egg development and juvenile growth of the Pacific cod Gadus macrocephalus (Korean East Sea Population) were studied to increase fry production using mass cultivation. The eggs were rectangular and adhesive sinking type. The egg size and fertilization rate were 1.01-1.09 mm and 72.4%, respectively. The cumulative times for egg hatching at 3, 6, 9, and $12\;^{\circ}C$ were 600, 360, 240, and 192 hrs, respectively. The hatching rates at 3, 6, 9, and $12\;^{\circ}C$ were 60.2, 68.9, 62.5, and 40.6%, respectively. After 11, 45, and 90 days, the larvae grew to a total length of 5.46-5.99, 9.42-10.06, and 23.0-32.0 mm, respectively. At 100 days from hatching, they grew to an average of 30 mm with a 7.1 % survival rate. By 312 days, juveniles with a total length of 3.6 cm grew to a total length of 14.7-20.1 cm and a body weight of 38.4-73.9 g. The specific growth rates of total length and body weight of the juveniles were 0.50% and 1.12%, respectively.

• 한국어류학회지
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• 제36권1호
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• pp.20-29
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• 2024

삼세기(Hemitripterus villosus)는 새로운 양식 어종으로 대두되고 있으나, 자원량이 감소하고 있으며, 양식 어종에서 지속적인 문제로 나타나는 골격 기형에 대해 삼세기의 정상적인 골격발달 기준을 제시하고자 한다. 이 연구에 사용된 시료는 어획된 어미로부터 채란된 수정란을 부화시킨 자치어를 포르말린액에 고정한 뒤 Kawamura and Hosoya (1991) 염색법에 따라 염색하여 골격발달을 관찰하였다. 부화 직후 평균전장 13.65±0.71 mm (n=5) 일 때 부설골과 주상악골, 전상악골, 치골이 골화되기 시작하였고, 부화 후 65일째 평균전장 21.24±0.50 mm (n=5) 일 때 사골과 안상골이 골화하면서 두부가 완성되었다. 견대부는 부화 7일째 평균전장 14.61±0.52 mm (n=5) 일 때 쇄골, 주새개골, 관절골이 골화하기 시작하였으며, 부화 44일째 평균전장 18.15±0.61 mm (n=5) 일 때, 4개의 사출골이 골화되어 견대부가 완성되었다. 부화 10일째 평균 전장 14.80±0.65 mm (n=5) 일 때 척추골의 골화가 시작되었으며, 부화 후 54일째 평균전장 18.67±0.54 mm (n=5) 일 때 척추골 추체 39개가 골화하여, 부화 60일째 평균전장 20.25±0.45 mm (n=5) 일 때 척추골의 골격이 완성되었다. 이 연구는 삼세기 자치어의 골격발달에 대한 것으로 삼세기의 자치어 골격 기형의 기준과 기초자료 연구에 사용될 것이다.