• 제목/요약/키워드: D.C

검색결과 26,656건 처리시간 0.045초

기존 교류선로의 직류변환 송전방식에 있어서 선정기법에 관한 연구 (A Study of Selection of Existing A.C. Transmission Facilities for Use with D.C.)

  • 김동준;문영환;이동일;윤재영;양광호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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    • pp.283-285
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    • 2002
  • The paper describes a study of selection of existing a.c. Transmission facilities converted fur use with d.c. system. In order to increasing the power transfer capability of existing a.c. transmission facilities, d.c. is one of good alternatives. Some advantages and disadvantages of this method are discussed, and the selection method of existing transmission facilities for use with d.c. considering economics and stability is presented in this paper.

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Integration Process and Reliability for $SrBi_2$ $Ta_2O_9$-based Ferroelectric Memories

  • Yang, B.;Lee, S.S.;Kang, Y.M.;Noh, K.H.;Hong, S.K.;Oh, S.H.;Kang, E.Y.;Lee, S.W.;Kim, J.G.;Shu, C.W.;Seong, J.W.;Lee, C.G.;Kang, N.S.;Park, Y.J.
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제1권3호
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    • pp.141-157
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    • 2001
  • Highly reliable packaged 64kbit ferroelectric memories with $0.8{\;}\mu\textrm{m}$ CMOS ensuring ten-year retention and imprint at 125^{\circ}C$ have been successfully developed. These superior reliabilities have resulted from steady integration schemes free from the degradation, due to layer stress and attacks of process impurities. The resent results of research and development for ferroelectric memories at Hynix Semiconductor Inc. are summarized in this invited paper.

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CAUCHY-RASSIAS STABILITY OF A GENERALIZED ADDITIVE MAPPING IN BANACH MODULES AND ISOMORPHISMS IN C*-ALGEBRAS

  • Shin, Dong Yun;Park, Choonkil
    • 충청수학회지
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    • 제24권4호
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    • pp.617-630
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    • 2011
  • Let X, Y be vector spaces, and let r be 2 or 4. It is shown that if an odd mapping $f:X{\rightarrow}Y$ satisfies the functional equation $${\hspace{50}}rf(\frac{\sum_{j=1}^{d}\;x_j} {r})+\;{\sum\limits_{\iota(j)=0,1 \atop {\sum_{j=1}^{d}}\;{\iota}(j)=l}}\;rf(\frac{\sum_{j=1}^{d}{(-1)^{\iota(j)}x_j}}{r}) \\({\ddag}){\hspace{160}}=(_{d-1}C_l-_{d-1}C_{l-1}+1)\;{\sum\limits_{j=1}^{d}\;f(x_j)}$$ then the odd mapping $f:X{\rightarrow}Y$ is additive, and we prove the Cauchy-Rassias stability of the functional equation in Banach modules over a unital $C^*$-algebra. As an application, we show that every almost linear bijection $h:{\mathcal{A}}{\rightarrow}{\mathcal{B}}$ of a unital $C^*$-algebra ${\mathcal{A}}$ onto a unital $C^*$-algebra ${\mathcal{B}}$ is a $C^*$-algebra isomorphism when $h(2^nuy)=h(2^nu)h(y)$ for all unitaries $u{\in}{\mathcal{A}}$, all $y{\in}{\mathcal{A}}$, and $n=0,1,2,{\cdots}$.

GPS Baseband Chip 개발 (Development of GPS Baseband Chip)

  • 조재범;이태형;이윤직;허정훈;정휘성;정준영;윤석기;김학수;조동식;최훈순
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 D
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    • pp.2313-2315
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    • 2003
  • This paper presents the development methods which Samsung GPS baseband chip is called S3E4510X. Specification of S3E4510X and design methodology of baseband architecture is presented with a study of their effects. Also GPS core block and software are described in detail. We designed and implemented the test board with RF module for evaluating performance via static test dynamic test and each performance factors using live signal and CPS simulator. Test results show that our development GPS baseband chip have effectively performance for mobile handset Location Based Service (LBS) and its practical use for navigation.

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런닝형 브래지어의 비교분석 (Comparative analysis of running-type brassieres on the market)

  • 박도윤;정혜순;나미향
    • 복식문화연구
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    • 제20권5호
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    • pp.621-634
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    • 2012
  • With comparative analysis of running-type brassieres on the market about suitability for middle-aged women, this study is to provide basic data of running-type brassieres' pattern which is highly suitable. In the pursuit of this purpose, this study carried out wearing experiment targeting 3 middle-aged women with normal body shape which is 85B of chest circumference. The result is as follows. The significant difference was recognized in the breast. The products were rated in order of C>A>B>D, E, F, G>H by the observers, and C>B>D>A>F>E=G>H by the subjects. The significant difference was recognized in the armhole area. The products were ranked in the order of C, D>B, G, E>A, F, H by the observes and D, C>B>G>F>A>H by the subjects. The significant difference was also recognized in 6 categories(14~19) for the torso. According to the overall average values, the products were rated in the order of B, C, D>A, D, F, G by the observers and B=D>C>H>F>G>A>E by the subjects. The overall evaluation exhibited the significant difference. The products were ranked in the order of D>C>E>B>H>A>G>F by both observers and subjects. Therefore it was confirmed that the product D was appropriate in general. To conclude of comparative analysis about 8 kinds of running-type brassieres on the market, the average values of the product C and D in all categories had high marks for each category. The product C was comfortable and capable of covering the breast well, however, a gap was formed in outside-up part. The product D, made from lacy fabric, was very comfortable and well-fitted but there was inconsistency between the mold-cup and the breast shape.

한국에 있어서 지자기 영년변화의 측정 (Measurement of Archaeomagnetic Secular Variation in Korea)

  • 성형미
    • 한국제4기학회지
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    • 제16권2호
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    • pp.33-38
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    • 2002
  • 우리나라 남부지방의 28기 유구의 소토에서 정방위시료를 채취하여 고고지자기 측정법으로 우리나라에서의 과거 지자기 방향을 구하였다. 이 자료의 연대는 A.D. 3∼9세기, A.D. 1317년, A.D. 15∼16세기에 걸쳐있다. A.D. 5∼6세기의 우리나라 지자기 방향은 같은 시기 일본의 지자기 방향과 매우 유사하나, A.D. 3∼4세기의 우리나라 지자기 방향은 같은 시기의 일본의 지자기 방향보다 크게 동쪽으로 편향하고 있었다. 이러한 차이는 A.D. 3∼4 세기경에 우리나라와 일본 부근에 현저한 국가적 지자기 이상이 있었음을 의미한다. A.D. 3∼6세기와 A.D. 7∼9세기의 우리나라 지자기영년변화곡선의 개형이 구해졌으며, 이것을 사용하여 유물이 출토되지 않아 연대를 알 수 없는 유적에서 소토를 이용하여 대략의 연대치를 측정할 수 있다.

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알 및 알가공품의 유통기한 설정을 위한 지표개발 및 산출 연구 (A Study of Establishment and Exploitation of Bio-markers for Determination of Shelf-life of Eggs and Egg Products)

  • 안지희;박정민;구자경;윤수진;이정수;김장미;김세헌;김영주;박재우;송성옥;위성환;김진만
    • 한국축산식품학회지
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    • 제32권3호
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    • pp.354-363
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    • 2012
  • 본 연구는 국내에서 유통되고 있는 식용란 및 전란액의 품질지표설정을 통하여 유통기한을 산출하기 위해 수행하였다. 식용란은 및 전란액(살균, 비살균)에 대한 저장기간별 저장온도에 따른 미생물학적, 이화학적, 관능적 특성을 측정하였다. 품질지표 개발을 위해 저장기간별 저장온도에 따라 식용란은 세균수, 대장균군, Salmonella sp., VBN, pH, 산가, Haugh unit을 품질지표로 설정하여 측정하였으며, 전란액은 Haugh unit을 제외하여 측정하였다. 유통기한은 품질지표 중 가장 먼저 품질한계에 도달한 성상(관능)을 근거로 하여 $10^{\circ}C$에서는 42일, $15^{\circ}C$에서는 27일,$25^{\circ}C$에서는 9일, $35^{\circ}C$에서는 2일, $45^{\circ}C$에서는 1일로 산출하였다. 전란액은 품질지표 중 가장 먼저 품질한계에 도달한 세균수를 근거로 하였으며, 살균전란액은 $10^{\circ}C$에서는 7일, $15^{\circ}C$에서는 3일, $25^{\circ}C$에서는 2일, $35^{\circ}C$에서는 1일, $45^{\circ}C$에서는 1일 미만으로 산출하였고 비살균전란액은$10^{\circ}C$에서는 4일, $15^{\circ}C$에서는 2일, $25^{\circ}C$에서는 1일, $35^{\circ}C$$45^{\circ}C$에서는 1일 미만으로 유통기한을 산출하였다. 결론적으로 저장기간과 가장 높은 상관관계를 가진 온도의 품질 한계일을 유통기한으로 산출하였다. 따라서 식용란은 27일, 살균전란액은 7일, 비살균전란액은 4일로 유통기한을 산출하였다.

Combined Effect of Aging and Irradiation on Physicochemical Quality of Pork Shoulder

  • Yim, Dong-Gyun;Jo, Cheorun;Mahabbat, Ali;Park, Ji-Young;Lee, Seong-Yun;Nam, Ki-Chang
    • 한국축산식품학회지
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    • 제39권3호
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    • pp.510-519
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    • 2019
  • The effect of combined electron-beam irradiation and aging temperature of pork on microbiological and physicochemical properties was investigated. The samples from pork shoulder were irradiated with 0 or 2 kGy, vacuum-packaged, and assigned randomly to an aging temperature ($2^{\circ}C$, $10^{\circ}C$, or $25^{\circ}C$) during 8 d. On 4 d of aging at $25^{\circ}C$, total aerobic bacteria of non-irradiated ones reached 7 Log CFU/g which is no salable levels. Shear force values of irradiated meat after aging for 2 and 4 d at $25^{\circ}C$ was lower than those aged at $2^{\circ}C$. Irradiated samples at $2^{\circ}C$ had lower cooking loss after 2 and 8 d of aging, compared with other aging temperatures. Irradiation did not accelerate 2-thiobarbituric acid reactive substance (TBARS) value when aged up to 4 d. Irradiated samples aged at $10^{\circ}C$ and $25^{\circ}C$ for 8 d scored significantly higher TBARS values. With an increased aging period, $a^*$ and $b^*$ in irradiated samples at $2^{\circ}C$ slightly increased, but irradiation caused negligible changes in meat color. The highest contents of a desirable nucleotide flavor compounds (inosine-5-phosphate) were observed in pork at $2^{\circ}C$ when aged for 4 and 8 d, while the lowest contents were observed at $25^{\circ}C$. Aging in irradiated pork for 8 d at $2^{\circ}C$ resulted in optimal condition with improved meat quality and minimal microbiologically negative defect.

ON BOUNDARY REGULARITY OF HOLOMORPHIC CORRESPONDENCES

  • Ourimi, Nabil
    • 대한수학회지
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    • 제49권1호
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    • pp.17-30
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    • 2012
  • Let D be an arbitrary domain in $\mathbb{C}^n$, n > 1, and $M{\subset}{\partial}D$ be an open piece of the boundary. Suppose that M is connected and ${\partial}D$ is smooth real-analytic of finite type (in the sense of D'Angelo) in a neighborhood of $\bar{M}$. Let f : $D{\rightarrow}\mathbb{C}^n$ be a holomorphic correspondence such that the cluster set $cl_f$(M) is contained in a smooth closed real-algebraic hypersurface M' in $\mathbb{C}^n$ of finite type. It is shown that if f extends continuously to some open peace of M, then f extends as a holomorphic correspondence across M. As an application, we prove that any proper holomorphic correspondence from a bounded domain D in $\mathbb{C}^n$ with smooth real-analytic boundary onto a bounded domain D' in $\mathbb{C}^n$ with smooth real-algebraic boundary extends as a holomorphic correspondence to a neighborhood of $\bar{D}$.