• Title/Summary/Keyword: 수준기

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중전기 산업의 기반기술 구축-초고압 전력기기 국산화-

  • 김중한
    • 전기의세계
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    • v.46 no.7
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    • pp.51-54
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    • 1997
  • 우리나라의 초고압 전력기기 분야는 선진국에서의 중전기 산업의 전반적 퇴조, 중동지역에서의 송변전설비의 수요증가, 동남아지역의 빠른 경제성장에 따른 전력설비의 증설, 한전의 2000년대 초로 예정된 765kV 송전 격상사업에 대비한 준비활동으로 생산, 수출, 연구개발 등에 있어서 비약적인 발전을 이룩하고 있다. 국내 중전기 산업이 이러한 호기를 효과적으로 이용할 수 있게된 배경에는 선진국에서의 중전기 산업의 일부 사업조정 및 1960년 이후로 지속적으로 추진되어온 국내 중전기 산업의 육성 정책과 연구개발 노력의 일환이라고 하겠다. 그러나 아직까지 국내 중전기 업체의 기술수준은 선진 외국회사와의 기술차이를 나타내고 있으며 중전기 산업의 기반 기술구축을 위한 초고압 전력기기의 국산화 연구개발은 지속되어야 할 것이다.

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On A Hybrid Binary Sequence Generator (혼합형 이진 수열 발생기)

  • 이훈재
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.7 no.4
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    • pp.81-90
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    • 1997
  • 키 수열 발생기는 함수 조합 형태에 따라 여러 가지로 분류될 수 있으며, 비도 기본 요소(랜덤 특성, 주기, 선형 복잡도, 상관 면역도, 키 수열의 수 등)는 비선형 함수에 따라 달라진다. 모든 기본 요소를 잘 만족하는 키 수열 발생기는 설계가 어렵지만, 각 요소별로 특성이 뛰어난 발생기를 잘 조합하면 고비도 시스템을 설계할 수 있다. 본 논문에서는 선형 복잡도와 상관 면역도 측면에서 강한 개선된 합산 수열 발생기와 키 수열 수사 많은 일반화된 메모리 다수열 발생기를 조합하여 혼합형 수열 발생기를 제안하고, 비도 수준을 분석하였다.

Prediction of Citizens' Emotions on Home Mortgage Rates Using Machine Learning Algorithms (기계학습 알고리즘을 이용한 주택 모기지 금리에 대한 시민들의 감정예측)

  • Kim, Yun-Ki
    • Journal of Cadastre & Land InformatiX
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    • v.49 no.1
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    • pp.65-84
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    • 2019
  • This study attempted to predict citizens' emotions regarding mortgage rates using machine learning algorithms. To accomplish the research purpose, I reviewed the related literature and then set up two research questions. To find the answers to the research questions, I classified emotions according to Akman's classification and then predicted citizens' emotions on mortgage rates using six machine learning algorithms. The results showed that AdaBoost was the best classifier in all evaluation categories. However, the performance level of Naive Bayes was found to be lower than those of other classifiers. Also, this study conducted a ROC analysis to identify which classifier predicts each emotion category well. The results demonstrated that AdaBoost was the best predictor of the residents' emotions on home mortgage rates in all emotion categories. However, in the sadness class, the performance levels of the six algorithms used in this study were much lower than those in the other emotion categories.

Acute Toxicity of Nitrite, Ammonia and Hydrogen Sulfide for Early Developmental Stages of Fenneropenaeus chinensis (대하의 초기생활사에 있어 아질산, 암모니아 및 황화수소의 급성독성)

  • Ji, Jeong-Hun;Gang, Ju-Chan
    • Journal of fish pathology
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    • v.17 no.3
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    • pp.199-205
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    • 2004
  • Effects of nitrite, ammonia and hydrogen sulfide on survival of the early developmental stages of Fenneropenaeus chinensis were determined under continuous flow-through system. The 96hr-$LC_{50}$ values of mysis stage were 18.4 mg/L, 0.69 mg/L and 13.5 $\mu{g}/L$ for nitrite, ammonia and hydrogen sulfide, respectively; 28.3 mg/L, 1.23 mg/L and 20.7 $\mu{g}/L$ for post larva stage and 39.8 mg/L, 1.73 mg/L and 28.5 $\mu{g}/L$ for juvenile stage, respectively. The Fenneropenaeus chinensis sensitivity for the three pollutants was in the order of hydrogen sulfide>ammonia>nitrite. The mysis/post larva, mysis/juvenile and post larva/juvenile ratios of nitrite, ammonia and hydrogen sulfide toxicity were >1.5, >2.0 and <1.5 times, respectively, and mysis were found to be more sensitive to pollutants than juvenile in all cases.

Transition in Living Arrangement and Life Satisfaction in Old Age (노년기 거주형태 변화와 삶의 만족도)

  • Baik, Ok Mi
    • The Journal of the Convergence on Culture Technology
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    • v.4 no.4
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    • pp.301-308
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    • 2018
  • This study examined the relationship between transition in living arrangement and life satisfaction outcomes among older adults in Korea. This study utilized the secondary data of 2 waves(2005-2011) of a Korean Retirement and Income Study from the National Pension Research Institute. This study categorized living arrangement transition over time into 16 categories and used generalized the estimation equation(GEE) modeling to examine the relationship between living arrangement transition group membership and life satisfaction. The results showed that transition in living arrangement in old age was partly and significantly associated with life satisfaction in later life. In particular, the best living arrangement type in older adults in terms of life satisfaction was the coresidence with spouse compared with residence alone or residence with their children. The group of residence with their children was not related to higer satisfaction. More research is needed to explore the mechanism behind older people's trajectory in transition in living arrangement.

An Analysis of Geometrical Differentiated Teaching and Learning Materials Using Inner Structure of Mathematics Problems (수학 문제의 내적구조를 활용한 기하 영역의 수준별 교수-학습 자료의 분석 연구)

  • Han, In-Ki
    • Communications of Mathematical Education
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    • v.23 no.2
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    • pp.175-196
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    • 2009
  • In this paper we analyze Ziv's geometrical differentiated teaching and learning materials using inner structure of mathematics problems. In order to analyze inner structure of mathematics problems we in detail describe problem solving process, and extract main frame from problem solving process. We represent inner structure of mathematics problems as tree including induced relations. As a result, we characterize low-level problems and middle-level problems, and find some differences between low-level problems and middle-level problems.

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