• 제목/요약/키워드: S-I-R

검색결과 4,007건 처리시간 0.032초

허용전류 관점에서의 전력케이블 최적 도체 크기 선정에 관한 연구 (A Study on the optimal conductor size selection of power cables considering the ampacity (I))

  • 정성환;최상봉;남기영;류희석;이재덕
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
    • /
    • pp.396-398
    • /
    • 2005
  • IEC 60287-3-2 standards suggests the selection method of economic conductor size for power cables. This method deals solely with the economic choice of conductor size based on joule losses. This paper introduces the method and example study which is proposed by IEC standards.

  • PDF

카나다 보포트-맥켄지 분지의 일라이트/스멕타이트 혼합층 점토광물 연구 (Mineralogy of Illite/smectite Mixed-Layer Clays from the Beaufort-Mackenzie Basin, Arctic Canada)

  • 고재홍
    • 자원환경지질
    • /
    • 제28권4호
    • /
    • pp.327-335
    • /
    • 1995
  • 카나다 극지의 보포트-맥켄지 (Beaufort-Mackenzie) 분지에 분포하는 일라이트/스멕타이트 (illite/smectite)에 대한 광물학적 특성 연구가 육상 및 대륙붕의 석유시추공으로부터 215개 코아와 파쇄시료를 대상으로 수행되었다. 보포트-맥켄지 분지의 일라이트/스멕타이트는 구성층의 배열 양상에 따라 불규칙, R1-배열, R>1-배열, 불규칙과 R1-배열의 혼합으로 구분된다. 불규칙과 규칙적인 배열의 혼합 양상을 보이는 일라이트/스멕타이트는 불규칙으로부터 R1-배열로 변화하는 전이대에서 나타나는데 혼합층의 배열이 규칙화하는 과정에서 불안정하게 나타나는 준안정상으로 해석된다. 불규칙과 규칙 배열을 갖는 일라이트/스멕타이트가 함께 나타나는 현상은 느린 화학반응에서 흔히 관찰되는 반응물과 생성물이 공존하는 현상과 일맥 상통한다. K-포화 실험결과는 일라이트/스멕타이트 내의 스멕타이트층의 층전하가 다양함을 보여준다. 높은 층전하의 스멕타이트층은 K-포화시 준 일라이트층으로 변한다. K-포화는 일라이트/스멕타이트의 구성비와 배열을 변화시키는데 이는 자연에서의 일라이트화 현상도 기존 격자결합의 교란이 없이 일어날 수 있다는 것을 의미한다.

  • PDF

난용계의 주요경제형질에 대한 유전력 및 유전상관 (Heritabilities and Genetic Correlations on Economic Traits in Layers)

  • 상병찬;한성욱;정선부
    • 한국가금학회지
    • /
    • 제16권2호
    • /
    • pp.73-81
    • /
    • 1989
  • 본 연구는 산란계의 개량을위한 주요 경제형질에 대한 유전력과 유전상관을 추정하고자 1980년 3월 1일부터 1981년 7월 31일까지 사육 되어온 S.C.W. Leghorn종 351수와 R. 1. Red종 326수에서 조사된 주요 경제형질에 대한 자료로서 얻어진 결과들을 요약하면 다음과 같다. 1. 체중은 S.C.W. Leghorn종과 R. I. Red종에서 각각 초산 시 1,409, 1,965 g이었고 300일영기 1,602, 2,305g이었으며, 500일영시 1,709, 2,479 g이었고, 초산일영은 S.C.W. Leghorn종과 R. I. Red종에서 각각 156, 163일이었다. 또한 산란수는 S.C.W,Leghorn종과 R. I. Red종에서 300일영시에 각각 101.18, 101. 05개이었고. 500 일영시에 각각 214.39 및 214.93개이었으며, 난중은 초산시에 41.93, 41.82g, 300일영시에 57.65, 57.62g, 500일영시에 60.33, 60.57g이었다. 2. 유전력 추정치에 있어서는 S.C.W. Leghorn종 및 R. I. Red종의 체중은 부분산성분에서 각각 0.492∼0.612, 0.309∼0.523이었고, 최분산성분에서 각각 0.275∼0.458, 0.134∼0.380으로 부분산성분에서 높았으며, 초산일영은 부분산성분에서 각각 0.167, 0.169이었고, 모분산성분에서 각각 0.169, 0.095로 낮은 추정치이었으며, 산란수는 부분산성분에서 각각 0.214∼0.239, 0.137∼0.259이었고, 모분산성분에서 각각 0.336∼0.341, 0.024∼ 0.102 이었으며, 난중은 부분산성분에서 각각 0.537∼0.796, 0.519∼0.631이었고, 모분산성분에서 각각 0.374∼0.686 및 0.116∼0.365로 부분산성분에서 높게 추정되었다. 3. 유전상관에서 S.C.W. Leghorn종과 R. I. Red종에서 체중과 초산일영간에는 각각 0.328∼0.426, 0.186∼0.244이었고, 체중과 산란수간에는-0.666∼-0.498, -0.542∼-0.073으로 員의 상관인 반면에, 난중과는 각각 0.384∼0.744, 0.126∼0.612로 정의 계수이었고, 초산일영과 산란수간에는 각각 -0.639∼-0.452, -0.754∼-0.320으로 높은 부의 상관인 반면에 난중과는 각각 0.478∼0.705, 0.021∼0.605로 정의 상관이었고, 산란수와 난중간에는 각각 -0.623∼-0.355, -0.861∼-0.327로 부의 상관계수이었다.

  • PDF

PROPERTIES OF INDUCED INVERSE POLYNOMIAL MODULES OVER A SUBMONOID

  • Cho, Eunha;Jeong, Jinsun
    • Korean Journal of Mathematics
    • /
    • 제20권3호
    • /
    • pp.307-314
    • /
    • 2012
  • Let M be a left R-module and R be a ring with unity, and $S=\{0,2,3,4,{\ldots}\}$ be a submonoid. Then $M[x^{-s}]=\{a_0+a_2x^{-2}+a_3x^{-3}+{\cdots}+a_nx^{-n}{\mid}a_i{\in}M\}$ is an $R[x^s]$-module. In this paper we show some properties of $M[x^{-s}]$ as an $R[x^s]$-module. Let $f:M{\rightarrow}N$ be an R-linear map and $\overline{M}[x^{-s}]=\{a_2x^{-2}+a_3x^{-3}+{\cdots}+a_nx^{-n}{\mid}a_i{\in}M\}$ and define $N+\overline{M}[x^{-s}]=\{b_0+a_2x^{-2}+a_3x^{-3}+{\cdots}+a_nx^{-n}{\mid}b_0{\in}N,\;a_i{\in}M}$. Then $N+\overline{M}[x^{-s}]$ is an $R[x^s]$-module. We show that given a short exact sequence $0{\rightarrow}L{\rightarrow}M{\rightarrow}N{\rightarrow}0$ of R-modules, $0{\rightarrow}L{\rightarrow}M[x^{-s}]{\rightarrow}N+\overline{M}[x^{-s}]{\rightarrow}0$ is a short exact sequence of $R[x^s]$-module. Then we show $E_1+\overline{E_0}[x^{-s}]$ is not an injective left $R[x^s]$-module, in general.

HOM AND EXT FUNCTORS OF GENERALIZED INVERSE POLYNOMIAL MODULES

  • Han, Chang-Woo;Park, Sang-Won;Cho, Eun-Ha
    • East Asian mathematical journal
    • /
    • 제16권1호
    • /
    • pp.111-123
    • /
    • 2000
  • Northcott and McKerrow proved that if R is a left noetherian ring and E is an injective left R-module, then $E[x^{-1}]$ is an injective left R[xl-module. Park generalize Northcott and McKerrow's result so that if R is a left noetherian ring and E is an injective left R-module, then $E[x^{-S}]$ is an injective left $R[x^s]$-module, where S is a submonoid of N(N is the set of all natural numbers). In this paper we show $$Hom_{R[x^S]}(M[x^{-S}],\;N[x^{-S}]){\cong}Hom_R(M,\;N)[[x^S]]$$ and using the above result and this isomorphism, finally we show that $$Ext^i_{R[x^S]}(M[x^{-S}],\;N[x^{-S}]){\cong}Ext^i_R(M,\;N)[[x^S]]$$.

  • PDF

핵심 잡지의 결정 요인에 관한 연구

  • 김선호
    • 정보관리학회지
    • /
    • 제5권1호
    • /
    • pp.53-78
    • /
    • 1988
  • The purpose of this study is to verify the factors determining core journals in a field based upon the results of the citation analysis of the journals in the field of Korean History(KH). In order to verify the determinant factors, dividing the articles of the KH journals into their novelty and author's seniority, the following hypotheses were established. Hypothesis 1: When a KH journal publishes more articles on prehistoric and ancient eras than others, the journal will have higher chance to be included in the core journals. Hypothesis 2: When a KH journal publishes more articles by senior researchers than others, the journal will have higher chance to be included in the core journals. To achieve the purpose, the cited articles found in the two sample journals, namely, Backsan Hakbo and Hanguksa Yongu were analysed during the past 20 years from 1962 to 1981. Applying the Hirst's Discipline Impact Factor method to the the study, Historical Science Impact Factor(HSIF) on the samples itself and the historical era dealt with in the articles and the seniority of the authors during every five-year period. Based upon thr present study to ver~fy the two hypotheses, the following conclusions have been reached. 1) Tht. most influencing sublect mattcr era or1 thix liSIF of the lo~lrual is arranged in prehistoric arid ancient, Koryo, Chosun, recent era, and the others by order of era. 2 ) Clial~g~~lg a fringe or semicore journal u~to a core j ~ u r n a l , very IISIF' 011 it> article e r a 1s grown up arrd prcllistoric a ~ ~ d ancierlt era:. are, s p c c ~ a l l ~ , incr.eased high relatively. Char~ging a core journal int:~ a fr~ngr or semicort. journal, t.very IISIF ti dropped and prel~istc~ric and ancieut taras arc, fallen sharp relatively. 3) The most irlflr~encin~ s~niority 011 the t1SII- of ihc journal I. the senior.., written or1 prehistoric and ancient eras. Above all, the senilir'b HSIF olr prehistoric anti anclent e r a s a r e most ~nfluencing the cliangi~rg of the core journal into the fringe ur bemicore. .i) flypothesis fl is no1 vcrif~ed i r t general. T l ~ e rt, lative connections bet wee^^ the senior's HSIF 011 each era and tht, ~ l ~ a l ~ g i t l g of the tort. ji1ur.tia1 arc \:er~fied in part hut r~ot in the wliole. 5) 'The reason why the 11SIF or1 prehistori~. arid ar~cic~nt e r a s is higl~er than others can be assumed becaltic the new <, xcavations a r r contit~ued actively i l l the prrsr.llt as to the relics arid remains or1 that eras. Accordingly, the HSIF' r i l l thr 11ew 3ubject matter l~ke arcl~acmlogy trends to grow up greatly. Bctween the senior's and juriior's JISIE', junior'.; is higl~er than s., nior's except ancient e r a . That reason can be assumed bccausr Iunlorb t r j to solve the ex~sting problems thr~urglr their ow11 new viewpoints and sights. So, i t should be studied whether the 11SlF on the artic1t.s of the new subject matters and viewpoirrts is influenced to the changing of the core jorlrnal or not.

  • PDF

도서관의 정보의뢰봉사에 관한 고찰 (A study on the information and referral services in libraries)

  • 손연옥
    • 한국도서관정보학회지
    • /
    • 제20권
    • /
    • pp.187-216
    • /
    • 1993
  • The overall goal of this study is to identify what I'||'&'||'R is, and what services should be offered as legitimate I'||'&'||'R actives. The gist of the study is as follows: 1. The shift of the clients targeted to receive the services from disadvantageous to every person. 2. Ambiguity in I'||'&'||'R definition. Because it is hard to distinguish I'||'&'||'R service from the traditional reference service, and shifting of clients, the establishment of the definition was very difficult. Instead of a definite answer, the criteria for "I'||'&'||'R Providers" was drawn. 3. Most provided services were simple and complex information giving based on resource file. Constructing resource file is a major component of I'||'&'||'R service. 4. From 1980s, many I'||'&'||'R providing libraries adapted computer a n.0, pplications. 5. Social work and library-internship was advised to conduct a cooperative project by NCLIS, I'||'&'||'R Task Force. 6. In the high technological era, there continue to be many people who need the su n.0, pportive relationship. I'||'&'||'R is to optimize both the service and clients. Librarian must learn from the principle of high tech/high touch.

  • PDF

제어봉 구동장치 제어기기 Prototype 개발 (Development of a Prototype Control Rod Control System)

  • 김춘경;천종민;김석주;이종무;안종보;권순만
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2002년도 하계학술대회 논문집 D
    • /
    • pp.2182-2184
    • /
    • 2002
  • In this paper we describe a prototype Control Rod Control System(CRCS). The CRCS controls the motion of the full length rod drive mechanisms in response to signals from the Reactor Operator and the Reactor Control System. Each mechanism belongs to either Shutdown Banks or Control Banks. The CRCS also provides information regarding the rod motion, rod position, and the status of the Rod Control System. The prototype CRCS will be used to obtain the requirements for detailed design of a full-scale CRCS.

  • PDF

Pairwise semicontinuous mapping in smooth bitopological spaces

  • Lee, Eun-Pyo
    • 한국지능시스템학회논문지
    • /
    • 제12권3호
    • /
    • pp.269-274
    • /
    • 2002
  • We introduce (${\tau}_i$, ${\tau}_j$) fuzzy (r,s)-semiclosures and (${\tau}_i$, ${\tau}_j$)-fuzzy (r,s)-semiinteriors. Using the notions, we investigate some of characteristic properties of fuzzy pairwise (r,s)-semicontinuous, fuzzy pairwise (r,s)-semiopen and fuzzy pairwise (r,s)-semiclosed mappings.