• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1047-1049
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• 2005

Hydraulic power plant is operated for peak load and frequently start-stop because of no continuous operation. So the fault can happen due to field voltage swing in the middle of starting or reactive power swing on the line. On this research, we want to analyze that this status influence on line and generator. we hope this research can contribute to the power quality improvement.

• Journal of Information Processing Systems
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• 제19권4호
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• pp.450-464
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• 2023

To address the problems of large system overhead and low timeliness when dealing with task scheduling in mobile edge cloud computing, a task scheduling and resource management strategy for edge cloud computing based on an improved genetic algorithm was proposed. First, a user task scheduling system model based on edge cloud computing was constructed using the Shannon theorem, including calculation, communication, and network models. In addition, a multi-objective optimization model, including delay and energy consumption, was constructed to minimize the sum of two weights. Finally, the selection, crossover, and mutation operations of the genetic algorithm were improved using the best reservation selection algorithm and normal distribution crossover operator. Furthermore, an improved legacy algorithm was selected to deal with the multi-objective problem and acquire the optimal solution, that is, the best computing task scheduling scheme. The experimental analysis of the proposed strategy based on the MATLAB simulation platform shows that its energy loss does not exceed 50 J, and the time delay is 23.2 ms, which are better than those of other comparison strategies.

• Composites Research
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• 제31권2호
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• pp.57-62
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• 2018

순수한 유리섬유와 두 가지 사이징제가 코팅된 유리섬유/폴리디사이클로펜타디엔(p-DCPD) 복합재료의 계면물성 및 상온($25^{\circ}C$)과 저온($-20^{\circ}C$)에서의 기계적 물성을 평가하였다. 섬유의 사이징제를 용출하기 위하여 아세톤을 이용하였고, 용액을 건조 후 각각의 용출물에 대하여 적외선 분광 분석을 통해 비교하였다. 동적접촉각 측정을 통하여 섬유와 p-DCPD의 표면에너지를 분석하였고 이를 통하여 접착일을 계산하였다. 서로 다른 유리섬유의 기계적 물성을 알아보기 위하여 단섬유 인장실험을 진행하였고, 단섬유와 p-DCPD의 계면적 물성을 알아보기 위하여 반복인장하중실험을 진행하였다. 상온 및 저온에서의 기계적 물성을 알아보기 위하여 인장, 굴곡, 아이조드 충격실험을 진행하였다. 실험결과 표면의 인자에 따라 계면 및 기계적 물성이 달라지는 것을 볼 수 있었다.

• 산업노동연구
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• 제24권2호
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• pp.409-441
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• 2018

이 글은 미국 최대 독립 정유회사인 Valero Energy에 대한 사례연구로서, 비노조 기업의 기업문화와 인적자원관리의 특징을 살펴보기 위한 목적 하에 작성되었다. 1980년 설립 이래 Valero는 유전지역인 텍사스 기반 지역기업으로서 남부지역 정서에 부합하는 비노조기업 성격이 뚜렷하다. 강력한 CEO 리더십, 종업원 최우선 정책과 팀워크 강조 문화, 확고한 고용보장정책(no lay-off policy) 및 인사업무 외주화 금지 정책, 업계 중상위권의 임금수준과 업계 최고 수준의 복리후생, 비노조전통과 이를 보완하는 공정한 고충해결 시스템 구비 노력 등 미국 비노조기업의 인적자원관리 특징들을 잘 보여주는 전형적인 예에 해당한다. 2010년 이전까지 엄청난 성장과 수익성 제고에 기반하여, 한계기업이 선호하는 노조압박방식 대신, 우량기업이 채택하는 노조대체방식을 노조회피전략의 구체적인 방안으로 실행하여 왔다. 하지만, 최근 들어, 지속적인 인수합병으로 인한 기업 인력 내 이질성 확대, 유가 하락 등으로 인한 고용보장정책 유지의 어려움과 정리해고 실시 필요성 증대 등으로 인해 Valero의 노조대체방식에 기반한 노조회피전략은 본격적인 시험대에 올라가고 있다.

• 한국가금학회지
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• 제48권4호
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• pp.319-325
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• 2021

In this study, we investigated the effects of feeding diets with different levels of energy and nutrient density on the egg quality of laying hens during the pre-peak and peak periods. A total of 192 (Hy-line brown) laying hens were used in a 15-week trial. The hens were randomly allotted to one of four treatments, each with four replicates (12 hens per replication). We assessed the effects of four level of dietary energy (2,710, 2,850, 2,870 and 2,890 kcal/kg) and three levels of nutrient density (Methionine + Cysteine: 0.56%, 0.85%, 0.80% and Crude Protein: 14.5%, 19%, 18%). Differences in the energy and nutrient density contents of diets showed no significant effect (P>0.05) on the average daily gain, average daily feed intake, feed conversion ratio, egg weight, or egg production of hens during the pre-peak and peak periods. However, hens subjected to 2,890 kcal/kg during the pre-peak period were found to lay eggs with significantly thicker shells, and yolk color was found to be significant enhanced in hens fed this diet during the pre-and peak periods. In contrast, we detected no significant effects of dietary energy or nutrient density on the Haugh unit or eggshell strength. In summary, increasing the energy level of diets from 2,710 to 2,890 kcal/kg was found to have positive effects on the shell thickness and yolk color of eggs produced by laying hens.

• 한국지반신소재학회논문집
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• 제22권3호
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• pp.105-117
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• 2023

최근 글로벌 에너지 공급 위기로 인해 국제 에너지 시장에서 불확실성이 증가되고 있다. 이러한 시장 변화로 에너지 가격이 상승하고 있으며, 미개발된 에너지 자원이 풍부하게 저장된 극한지(북극권)까지 개발 대상 지역이 확대되고 있다. 북극권은 기존 에너지 플랜트 사업을 수행하던 지역과 차별되는 자연환경, 법, 제도, 문화, 이해관계자 등 특수한 건설 환경을 가지고 있기 때문에 사전에 개발지역에 대한 다양한 검토가 필요하다. 본 논문에서는 최근 비전통 에너지 자원개발이 활발히 이루어지고 있는 캐나다 앨버타(Alberta)주를 대상으로 건설 환경 관련 공간정보를 수집하고 구축하였다. 또한, 건설 환경 공간정보 데이터를 활용하여 자원개발을 위한 최적 입지 평가 모델을 개발하고, 기존 자원개발 지역과 비교·분석하여 신뢰도를 검증하였다.

• 동력기계공학회지
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• 제20권4호
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• pp.44-51
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• 2016

An investigation on reliability of reanalysis wind data was conducted using the met mast wind data at four coastal regions, Jeju Island. Shinchang, Handong, Udo and Gangjeong sites were chosen for the met mast sites, and ERA-Interim and MERRA reanalysis data at two points on the sea around Jeju Island were analyzed for creating Wind Statistics of WindPRO software. Reliability of reanalysis wind data was assessed by comparing the statistics from the met mast wind data with those from Wind Statistics of WindPRO software. The relative error was calculated for annual average wind speed, wind power density and annual energy production. In addition, Weibull wind speed distribution and monthly energy production were analyzed in detail. As a result, ERA-Interim reanalysis data was more suitable for wind resource assessment than MERRA reanalysis data.

• Asian-Australasian Journal of Animal Sciences
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• 제24권10호
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• pp.1435-1439
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• 2011

This study was conducted to evaluate the effects of creep feed with different energy densities on litter performance. A total of 30 sows (Landrace${\times}$Yorkshire) and their litters were randomly assigned with 1, 2, or 3+parities into 1 of 3 treatments (10 sows). Dietary treatments were: i) CON (no creep feed), ii) LE (creep feed (DE 4,000 kcal/kg) from 5 d of age until weaning (21 d)), and iii) HE (creep feed (DE 5,000 kcal/kg) from 5 d of age until weaning). Each piglet was weighed at d 5, 10, 15, 21 (weaning), and d 7 postweaning to determine ADG. Creep feeding reduced concentrations of epinephrine, norepinephrine, and cortisol compared with those in CON group (p<0.05). Creep feeding reduced (p<0.05) the weaning-to-oestrus interval in sows. Piglets in the HE groups evidenced greater ADG (p = 0.024) and ADFI (p = 0.001) post-weaning than those in CON treatments. Creep feeding decreased (p<0.05) the suckling time of piglet in this study. In conclusion, creep feeding increased growth and feed intake of pigs after weaning. It can decrease the oestrus interval of sows. There was no difference between providing a high energy or a low energy creep fed diet to the piglets.

• 한국태양에너지학회 논문집
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• 제37권2호
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• pp.1-11
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• 2017

The investigation on reliability of ERA-Interim reanalysis wind data was conducted using wind data from the five met masts measured at inland and coastal areas, Jeju island. Shinchang, Handong, Udo, Susan and Cheongsoo sites were chosen for the met mast location. ERA-Interim reanalysis data at onshore and offshore twenty points over Jeju Island were analyzed for creating Wind Statistics using WindPRO software. Reliability of ERA-Interim reanalysis wind data was assessed by comparing the statistics from the met mast wind data with those predicted at the interest point using the Wind Statistics. The relative errors were calculated for annual average wind speed and annual energy production. In addition, the trend of the error was analyzed with distance from met mast. As a result, ERA-Interim reanalysis wind data was more suitable for offshore wind resource assessment than onshore.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2009년도 공동학술대회
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• pp.287-288
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• 2009

분산발전원의 위치 변경에 따른 전력조류 및 송전전력 손실 평가를 통하여 도시차원에 적합한 발전원 설치점 선정 기법의 개발이 시급하다. 본 연구에서는 전력손실을 고려하여, 분산전원이 주변의 모선 및 선로에 미치는 영향을 최소화 할 수 있도록, 분산전원의 설치지점을 선정하는 방안을 제안한다.