• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.3
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• pp.197-202
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• 1999

This study was conducted to evaluate the dry matter yield, quality and utilization of nutrients of crabgrass (Digitaria sanguinalis L.) dominant swards as a roughage sources. Dry matter yield of stages, chemical composition, DM digestibility was obserbed, and DM intake, digestibility and utilization of nitrogen and energy by Korean native goats was determined. Average DM yield of crabgrass dominant swards was obtained 8,473kg/ha, and average contents of CP, NDF, ADF and lignin was 13.0%, 74.1%, 38.6% and 10.4%, respectively. DM intake by Korean native goats was lower for crabgrass dominant swards than for sown grass swards(P>0.05). Digestibility of DM, celluar constituents, NDF and ADF by Korean native goats was significantly lower for crabgrass dominant swards than for sown grass swards(P<0.05). Utilization of nitrogen and energy by Korean native goats was significantly lower for crabgrass dominant swards than for sown grass sward(P<0.05). Above the results, although crabgrass dominant swards was lower than in DM yield, digestibility, and utilization of N and energy, but the DM yield of crabgrass dominant swards was obtained 8,471kg/ha without fertilizer. Therefore it appears that crabgrass dominant swards have a potential to provide roughage sources.

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.113-120
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• 2012

The purpose of this study was to find out the effect of a torrent control structure using customized tetrapods on the forest water quality, fishes, snials and streamwater ecology conservation and management. The study was conducted in the Honggye valley located in Sanchung-gun, Gyungsangnam-do, and stream water quality and streamwater ecology was compared before and during 2 years after construction of torrent control structure. After construction of the torrent control structure using customized tetrapods, pH of stream water didn't get out of the range of River water quality standard class I. After 2 years construction of the torrent control structure using customized tetrapods, Dissolved Oxygen concentration didn't change, and Electrical Conductivity measurements agreed well within the range of normal clean stream water quality. After construction of the torrent control structure using customized tetrapods, fishes and snials up and down stream movement didn't influence of the tetrapods dam. Stream water quality during 2 years after construction of the torrent control structure was similar to before construction. Therefore, it was find out that the torrent control structure didn't affect stream water quality and ecology.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.7
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• pp.685-692
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• 2009

This paper dealt with the development of the Framework for Multidisciplinary Design Optimization for the rotorcraft design concept and the building process of KHP(Korea Helicopter Project) - SDM(Simulation Data Management) system to manage various analysis data, which are used in the rotorcraft development phase. KHP-SDM RMDO(Rotorcraft Multidisciplinary Design Optimization) framework, which applied optimization modules of KHP-SDM and integrated the developed Multidisciplinary analysis modules, was constructed in the KHP-SDM. The results of the rotorcraft conceptual design using KHP-SDM RMDO showed that the framework was evaluated to be successfully constructed.

• Progress in Medical Physics
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• v.6 no.2
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• pp.29-34
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• 1995

The wedge factor is defined as a ratio of the absorbed dose in a phantom at a depth of reference point on the central axis with the wedge in the place to the absorbed dose at the same point with the wedge removed. We attempted to show the wedge factors dependence on the field sizes. The wedge factors were measured at various field sizes on 6MV and 15MV x-ray of Varian Clinac 1800 and 5MV x-ray of Philips SL75/5. The single wedge factor measured for a reference field size(10cmx10cm) may not be valid for all field sizes. For the thick wedge, especially an autowedge on Philips SL75/5 for maximum field size width 30cm. the error can be significant(6.6％). Therefore, in the presence of a wedge filter in the beam, a field size dependent wedge factor may be necessary in the treatment dose calculations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1213-1222
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• 2011

The aim of this research is to map the intellectual structure of the field of LED and optics during the period of 2000-2009. We utilize the scientometric tool of co-word analysis to reveal patterns and trends in the LED and optics field by measuring the association strengths of keywords (or IPCs). Data were collected from Science Citation Index Expanded (SCIE) and United Stated Patent and Trademark Office (USTPO) for the period of 2000-2009. Keywords were extracted from abstracts and further standardized using thesaurus. In order to trace the dynamic changes of the LED and optics field, the whole 10-year period was separated into two consecutive periods: 2000-2004 and 2005-2009. The results show that the LED and optics field has some established research themes and it also changes to embrace new themes.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.6
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• pp.568-583
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• 2015

In this paper, the conceptual design procedure and results of Earth observation satellite through Multidisciplinary Design Optimization (MDO) are described. The conceptual design equations for major parameters are developed based on the established database of Earth observation satellite so far. The MDO conceptual design tool for Earth observation satellite was developed by applying the Collaborative Optimization (CO) architecture amongst several MDO architecture techniques available today. The objective for this research was set to minimize the total mass of satellite as well as satisfy all design constraints by utilizing the Sequential Quadratic Programming (SQP) algorithm. Eventually the effectiveness of MDO conceptual design tool was verified through proposing a comparison between the conceptual design results with MDO applied and the design specification of ASNARO-1 & IKONOS-2 Earth observation satellite.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.17 no.1
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• pp.32-39
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• 2006

Objectives : The aim of this study was to examine the developmental and clinical characteristics associated with nocturnal enuresis in Korean children. Methods : Three hundred eighteen children with nocturnal enuresis, together with their parents, completed a parent questionnaire consisting of a Child Behavior Checklist(CBCL). Data related to the prenatal, perinatal and developmental history, past and current medical history were collected. Ninety-three normal students were selected as the control group. Results : The nocturnal enuresis group attained diurnal and nocturnal urinary control significantly later than those in the normal control group.49.2% of the children with nocturnal enuresis had the family history of nocturnal enuresis. Daytime incontinence was present in 41.3% of the nocturnal enuresis group. The percentages of sleep-related disturbances were significantly higher in the nocturnal enuresis group when compared to the normal control group.42.6% of the children with nocturnal enuresis experienced pharmacotherapy, and 0.4% experienced enuresis alarms. Conclusion : The results of this study suggest that children with nocturnal enuresis in Korea have a high genetic load and a possibility of developmental delay, which supports the neurodevelopmental point of view with regard to the etiology of nocturnal enuresis. The physicians in Korea prefer pharmacological interventions to alarm interventions in treating Korean children with nocturnal enuresis.

• Childhood Kidney Diseases
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• v.15 no.2
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• pp.146-153
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• 2011

Purpose : Hypercalciuria has been suggested to be involved in the pathogenesis of nocturnal enuresis associated with polyuria. We have measured the amount of calcium excretion in the urine from children with monosymptomatic nocturnal enuresis and studied the association with enuresis. Methods : Thirty-six children (20 males and 16 females, age 5 to 15.6 years) presenting with monosymptomatic nocturnal enuresis were recruited for this study. Results : Among 36 patients, 6 patients had hypercalciuria, providing a 16.7% frequency. The mean Ca/Cr ratio of hypercalciuria group showed $0.23{\pm}0.10$ on daytime, and $0.33{\pm}0.10$ on nighttime showing higher values in nighttime, but it was not statistically significant. Average 24 hour calcium excretion was 8.95 mg/kg. Night/day time urine volume ratio in hypercalciuria group was $0.87{\pm}0.20$, and that in normocalciuria group was $0.81{\pm}0.33$, also showing no difference. Daytime Ca/Cr ratio and nighttime Ca/Cr ratio from all enuresis patients showed a significant correlation (P=0.0001). However, Ca/Cr ratio between daytime and nighttime urine volume had no significant correlation, respectively (daytime P=0.08; nighttime P=0.07). Also, daytime and nighttime Na concentration, urea concentration, and osmolality also had no significant correlation with urine Ca/Cr ratio, respectively. Conclusion: Hypercalciuria shown in some of enuresis patients is not directly caused by primary monosymptomatic nocturnal enuresis.

• Computational Structural Engineering
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• v.17 no.3
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• pp.14-21
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• 2004

MDO프레임웍은 설계 작업을 통합적으로 관리하고 자동화하여 설계도구 간의 데이터 전달과 변환에 소요되는 설계자의 부담을 경감시키며 다분야 전문가가 참여하는 협동설계 환경을 제공함으로써 다분야를 동시에 고려한 효율적 설계를 지원한다. 이번 글에서는 이러한 MDO프레임웍으로 개발된 EMDIOS를 소개하고, 그 개발 배경과 타당성을 개략적으로 제시하였다. EMDIOS는 분산 환경을 제공하고, 데이터베이스와 연계되어 정의된 문제와 문제 풀이 절차를 저장하고 실행시 발생하는 데이터들을 체계적으로 관리하는 구조를 갖는다. MDO문제 해결에 필요한 도구들은 모두 소프트웨어 컴포넌트로 구성 및 기술되어 컴포넌트 등록기에 등록되어 저장된다. 등록된 컴포넌트는 GUI기반의 MDO커널에 의하여 검색되고 MDO문제해결 절차의 구성 요소가 된다. 구성된 문제 해결을 위한 실행은 컴포넌트 서비스 에이전트에 의하여 이루어진다. EMDIOS는 새로운 설계도구를 EMDIOS에 쉽게 통합하여 사용할 수 있도록 공통적으로 구현될 수 있는 부분을 구현한 추상 클래스와 이로부터 필요한 인터페이스를 생성할 수 있는 인터페이스 제조기를 제공함으로써 확장성과 개방성을 제공한다. 제시된 MDO 프레임웍의 사용자 인터페이스는 가장 많은 사용자를 확보하고 있는 윈도우 환경에서 Visual C++를 이용하여 개발되고 있으며, 다양한 OS환경에서 작동되어야 하는 래퍼는 JAVA로 개발하였다. 현재 개발된 EMDIOS는 다양한 벤치 마크 테스트 중이며 올해 9월이후에는 일반에게도 공개할 수 있는 프레임웍으로써 모습을 갖출 것으로 보인다.

• CDE review
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• v.10 no.1
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• pp.48-54
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• 2004

제품설계에 관련된 다양한 공학해석분야, 즉 구조해석, 동역학, 열ㆍ유체ㆍ유동해석, 제어, 전자기장해석 등을 동시에 고려하면서 최적의 설계를 결정하는 것을 다분야통합최적설계(Multidisciplinary Design Optimization: MDO) 기술이라 한다. MDO 프레임적 (framework)은 최적화기술, 컴퓨팅기반구조기술, 통합설계기술이 유기적으로 구현된 소프트웨어 복합체계로서, 분산컴퓨팅 기반구조를 통하며 MDO요소 기술들과 기존의 CAD/CAE 도구들을 연계하여 설계 작업을 통합적으로 관리하고 자동화한다. MDO 프레임칙은 이러한 자동화된 통합관리를 통하여 설계도구 간의 데이터 전달과 변환에 소요되는 설계자의 부담을 경감시키며 다분야 전문가가 참여하는 공통 작업 환경을 제공함으로써 설계 효율성을 증진시킨다. 이 글에서는 현재 최적설계신기술연구센터 (iDOT)에서 개발 중인 MDO 프레임웍인 EMDIOS를 소개하기로 한다.