• 한국농공학회논문집
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• 제48권1호
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• pp.27-38
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• 2006

In this study, we developed a program to estimate discharge efficiently considering major hydraulic characteristic including water level, river bed, water slope and roughness coefficient in a natural river. Stream discharge was measured at Gongju gauge station located in the down stream of the Daechung Dam during normal and dry seasons from 2003 to 2004. The developed model was compared with the results from the existing rating curve at T/M gage stations, and was used for runoff analyses. Evaluating the developed river discharge estimation program, it was applied during 1983-2004 that base flow separation method and RRFS (Rainfall Runoff Forecasting System) which is based on SSARR (Streamflow Synthesis And Resevoir Regulation). The result presents the stage-discharge curve creator range at the Gong-ju is overestimated by approximately $10-20\%$, especially at the low stage. It is attributed to the hydraulic characteristics at the study. The discharge simulated by the RRFS and base flow separation, which is calibrated using the measurement at the early spring and late fall season during relatively d]v season, shows the least errors. The coefficient of roughness at Gongju station varied with the high and low water level.

• Clinical and Experimental Pediatrics
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• 제59권12호
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• pp.466-470
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• 2016

Early, aggressive nutrition is an important contributing factor of long-term neurodevelopmental outcomes. To ensure optimal growth in premature infants, adequate protein intake and optimal protein/energy ratio should be emphasized rather than the overall energy intake. Minimal enteral nutrition should be initiated as soon as possible in the first days of life, and feeding advancement should be individualized according to the clinical course of the infant. During hospitalization, enteral nutrition with preterm formula and fortified human milk represent the best feeding practices for facilitating growth. After discharge, the enteral nutrition strategy should be individualized according to the infant's weight at discharge. Infants with suboptimal weight for their postconceptional age at discharge should receive supplementation with human milk fortifiers or nutrient-enriched feeding, and the enteral nutrition strategy should be reviewed and modified continuously to achieve the target growth parameters.

• 한국재료학회지
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• 제27권5호
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• pp.248-254
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• 2017

In the present work, graphene powder was synthesized by laser scribing method. The resultant flexible light-scribed graphene is very appropriate for use in micro-supercapacitors. The effect of the laser scribing process in reducing graphene oxide (GO) was investigated. GO was synthesized using a chemical mixture of GO solution; then, it was coated onto a LightScribe DVD disk and laser scribed to reduce GO and create laser-scribed graphene (LSG). The CV curves of pristine rGO at various scan rates showed that the ultimate product possesses the ability to store energy at the supercapacitor level. Charge-discharge curves of pristine rGO at two different current densities indicated that the specific capacitance ($C_m$) increases due to the reduction of the discharge current density. Finally, the long-term charge-discharge stability of the LSG was plotted and indicates that the specific capacitance decreases very slightly from its primary capacitance of ${\sim}10F\;cm^{-3}$ and that the cyclic stability is favorable over 1000 cycles.

• 생태와환경
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• 제46권2호
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• pp.205-214
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• 2013

영산강 하구에서 담수 유입이 부유생태와 수질에 미치는 영향을 파악하기 위해 국가해양환경측정망 장기자료(1999~2008년)인 클로로필 a와 수질 항목들에 대한 계절적, 공간적 변화와 장기변동 추세를 분석하였다. 분석결과, 여름철 (8월) 영산강 방조제 인접정점의 염분은 조사기간 중 가장 낮은 분포를 보였고, 영양염류와 클로로필 a는 전반적으로 높은 분포를 나타냈다. 영산강 담수유입의 지시인자인 표-저층의 염분차 (${\Delta}salinity$)와 영양염류, 클로로필 a는 유의한 양의 상관성을 나타냈으나, 지난 10년동안 담수 방류량은 감소하는 추세를 보였고, 영양염류, 클로로필 a는 전반적으로 증가하는 경향을 나타냈다. 이러한 결과는 영산강 하구 해역 영양염의 공급원이 담수유입뿐만 아니라 인근 지역의 발달에 따른 점오염원 증가 등의 추가적인 요인이 존재할 가능성을 제시한다. 따라서 영산강 하구 주변 해역의 부영양화 방지를 위해서는 영산강 방조제의 방류와 연관한 수질개선방안 마련과 더불어 인근 지역의 점 오염원 파악 및 관리가 병행되어야 할 것으로 사료된다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권5호
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• pp.213-221
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• 2002

In order to improve the reliability of XLPE cables, it is necessary to find the useful diagnostic parameter according to long term aging. This paper described the change of partial discharge(PD) phase Properties of XLPE cable insulation with branch type electrical tree degradation. for long term aging. To understand the PD Properties with $\phi$ -q-n distributed shape of XLPE insulation, specimens were prepared by 22.9㎸ distribution cable and made in a type of block(16${\times}$16${\times}$3[mm]). Ogura needles having tip radius of l0${\mu}{\textrm}{m}$ were inserted into each block pieces. The measuring system was consisted of PD detector, digitizer for digital conversion, VXI system for signal processing. The PD properties of the specimens were measured from initiation of tree to breakdown and their characteristics were analyzed. We analyzed the relationship between electrical properties(PD Quantity, PD initiation angle, PD extinction angle, PD occurrence angle : (PD extinction angle - PD initiation angle)) and the normalized aging rate. We found PD parameter, PD initiation angle and occurrence angle, which are a useful diagnostic parameter in estimating the branch type electrical tree for XLPE insulation condition.

• Nuclear Engineering and Technology
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• 제54권8호
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• pp.3034-3042
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• 2022

The results of radioecological monitoring of the cooling pond Beloyarsk NPP (Russia) have been presented. The influence of waste technological waters of thermal and fast NPP reactors on the content of artificial radionuclides in surface waters and bottom sediments of the Beloyarsk reservoir has been studied. The long-term dynamics of the specific activity of ⁶⁰Co, ⁹⁰Sr, ¹³⁷Cs and ³H in the main components of the freshwater ecosystem at different distances from the source of radionuclide discharge has been estimated. Critical radionuclides (⁶⁰Co and ¹³⁷Cs), routes of their entry and periods of maximum discharge of radioisotopes into the cooling pond have been determined. It is shown that the technology of electricity generation at Beloyarsk NPP, based on fast reactors, has a much smaller effect on the flow of artificial radionuclides into the freshwater ecosystem of the reservoir. During the entire period of monitoring studies, the decrease in the specific activity of radionuclides from NPP origin in surface waters was 4.3-74.5 times, in bottom sediments 10-505 times. The maximum discharge of artificial radionuclides into the reservoir was noted during the period of restoration and decontamination work aimed at eliminating emergencies at the AMB thermal reactors of the first stage of the Beloyarsk NPP.

• 중환자간호학회지
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• 제17권1호
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• pp.30-43
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• 2024

Purpose : Post-intensive care syndrome (PICS) is characterized by a constellation of mental health, physical, and cognitive impairments, and is recognized as a long-term sequela among survivors of intensive care units (ICUs). The objective of this study was to explore the impact of intensive care experience (ICE) on the development of PICS in individuals surviving critical care. Methods : This secondary analysis utilized data derived from a prospective, multicenter cohort study of ICU survivors. The cohort comprised 143 survivors who were enrolled between July and August 2019. The original study's participants completed the Korean version of the ICE questionnaire (K-ICEQ) within one week following discharge from the ICU. Of these, 82 individuals completed the PICS questionnaire (PICSQ) three months subsequent to discharge from hospital. The influence of ICE on the manifestation of PICS was examined through Partial Least Squares-Structural Equation Modeling (PLS-SEM). Result : The R² values of the final model ranged from 0.35 to 0.51, while the Q² values were all greater than 0, indicating adequacy for prediction of PICS. Notable pathways in the relationship between the four ICE dimensions and the three PICS domains included significant associations from 'ICE-awareness of surroundings' to 'PICS-cognitive', from 'ICE-recall of experience' to 'PICS-cognitive', and from 'ICE-frightening experiences' to 'PICS-mental health'. Analysis found no significant moderating effects of age or disease severity on these relationships. Additionally, gender differences were identified in the significant pathways within the model. Conclusion : Adverse ICU experiences may detrimentally impact the cognitive and mental health domains of PICS following discharge. In order to improve long-term outcomes of individuals who survive critical care, it is imperative to develop nursing interventions aimed at enhancing the ICU experience for patients.

• 한국수자원학회논문집
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• 제54권12호
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• pp.1223-1232
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• 2021

본 연구에서는 연중 일유량의 불균등 정도를 파악하기 위해 "유량 지니계수"라는 새로운 개념의 분석방법을 제시한다. 유량 지니계수는 오름차순한 연중 일유량 발생일자의 누계백분율과 일최빈유량의 오름차순 누계백분율과의 면적관계를 이용하여 산정한다. 유량 지니계수는 0~1 사이의 값으로 표현되며, 불균등의 정도는 5단계로 구분할 수 있다. 유량 지니계수를 이용하면 상류 지점에 대한 하류 지점의 유량 안정도를 산정할 수 있다. 또한, 유황분석 기준유량별로 불균등에 미치는 영향의 정도를 수치적으로 파악할 수 있다. 4대강 본류 상·하류 8개 지점의 장기간 일유량 자료를 이용하여 유량 지니계수의 적용성을 검토하였다. 유량지니계수는 상류 댐에 의한 하류에서의 유량조절 효과를 분석하는 데에도 활용될 수 있을 것이다.

• Journal of Korean Medical Science
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• 제33권48호
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• pp.309.1-309.13
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• 2018

Background: The aim of this study was to observe long-term outcomes of very low birth weight infants (VLBWIs) born between 2013 and 2014 in Korea, especially focusing on neurodevelopmental outcomes. Methods: The data were collected from Korean Neonatal Network (KNN) registry from 43 and 54 participating units in 2013 and 2014, respectively. A standardized electronic case report form containing 30 items related to long-term follow up was used after data validation. Results: Of 2,660 VLBWI, the mean gestational age and birth weight were $29^{1/7}{\pm}2^{6/7}$ weeks and $1,093{\pm}268g$ in 2013 and $29^{2/7}{\pm}2^{6/7}$ weeks and $1,125{\pm}261g$ in 2014, respectively. The post-discharge mortality rate was 1.2%-1.5%. Weight < 50th percentile was 46.5% in 2013 and 66.1% in 2014. The overall prevalence of cerebral palsy among the follow up infants was 6.2% in 2013 and 6.6% in 2014. The Bayley Scales of Infant Developmental Outcomes version II showed 14%-25% of infants had developmental delay and 3%-8% of infants in Bayley version III. For the Korean developmental screening test for infants and children, the area "Further evaluation needed" was 5%-12%. Blindness in both eyes was reported to be 0.2%-0.3%. For hearing impairment, 0.8%-1.9% showed bilateral hearing loss. Almost 50% were readmitted to hospital with respiratory illness as a leading cause. Conclusion: The overall prevalence of long-term outcomes was not largely different among the VLBWI born between 2013 and 2014. This study is the first large national data study of long-term outcomes.

• 한국수자원학회논문집
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• 제54권6호
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• pp.355-363
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• 2021

기존의 유황곡선은 일유량의 수문학적 지속성을 고려하지 못하며, 산술평균으로 인한 일유량의 왜곡이 발생되고, 특정유량의 발생시점이나 지속기간도 알 수 없다. 본 연구에서는 매년의 일유량을 발생일자별로 정렬한 후, 일 최빈유량을 산정하고, 이들을 5일 단위로 평균하여 나타내는 일 최빈유량곡선법을 제시하였다. 4대강 본류의 상·하류 각 1곳 씩 총 8개 지점의 장기간 관측 일유량 자료를 이용하여 검토한 결과, 연중 일유량은 수문학적 지속성을 가지는 것으로 나타났다. 또한, 일 최빈유량곡선법을 이용하면 산술평균에 따른 일유량의 왜곡을 완화시킬 수 있고, 특정유량의 발생시점과 지속기간도 파악할 수 있다. 일 최빈유량곡선법은 유황분석 기준유량별(갈수유량, 저수유량, 평수유량, 풍수유량, 홍수유량)로 유용하게 활용할 수 있다.