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CHARACTERIZATIONS OF THE POWER FUNCTION DISTRIBUTION BY THE INDEPENDENCE OF RECORD VALUES

  • Chang, Se-Kyung
    • 충청수학회지
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    • 제20권2호
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    • pp.139-146
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    • 2007
  • In this paper, we present characterizations of the power function distribution by the independence of record values. We establish that $X{\in}$ POW(1, ${\nu}$) for ${\nu}$ > 0, if and only if $\frac{X_{L(n)}}{X_{L(n)}-X_{L(n+1)}}$ and $X_{L(n)}$ are independent for $n{\geq}1$. And we prove that $X{\in}$ POW(1, ${\nu}$) for ${\nu}$ > 0; if and only if $\frac{X_{L(n+1)}}{X_{L(n)}-X_{L(n+1)}}$ and $X_{L(n)}$ are independent for $n{\geq}1$. Also we characterize that $X{\in}$ POW(1, ${\nu}$) for ${\nu}$ > 0, if and only if $\frac{X_{L(n)}+X_{L(n+1)}}{X_{L(n)}-X_{L(n+1)}}$ and $X_{L(n)}$ are independent for $n{\geq}1$.

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Correlator Design for L1/L2C GPS Signal

  • Chang, Jae-Won;Kim, Keun-Taek;Lee, Sang-Jeong
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.2623-2626
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    • 2003
  • GPS provides two services which include SPS(Standard Positioning Service) and PPS(Precise Positioning Service). While SPS users can navigate in more precise due to cancellation of SA(Selective Availability), SPS users has still less precision navigation than PPS users. L1/L2CS integrated receiver can provide more precise navigation to SPS users because the delay of Ionosphere will be cancelled by using two frequencies (L1 and L2). This paper designs an integrated L1/L2CS digital correlator to prepare the L2C signal that will be provided in 2003. Also L2CS transmitter is designed to confirm L2CS correlator.

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고정화균체 반응기에서 L-Sorbose 연속생산

  • 신혜원;신봉수;신철수
    • 한국미생물·생명공학회지
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    • 제25권1호
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    • pp.68-74
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    • 1997
  • The conversion of D-sorbitol to L-sorbose by Gluconobater suboxydans was analyzed, and continuous production of L-sorbose was carried out in immobilized cell reactors. L-Sorbose production by high densities of resting cells was more effective than by conventional batch fermentations. Sorbitol dehydrogenase, an enzyme converting D-sorbitol to L-sorbose, did not suffer from substrate inhibition, but from product inhibition. When L-sorbose production was carried out with Ca-alginate-immobilized cells, about 60 g/l of L-sorbose was obtained. On the other hand, when the corn steep liquor (CSL) concentration of medium was reduced to 0.08%, 80 g/l of L-sorbose was obtained. Outgrowth inside the immobilized carriers was thought to block the pores of the carriers so that substrate could not easily diffuse through the carriers. Continuous production of L-sorbose was well accomplished in a bubble column reactor, and 6. 5 g/l.h of productivity and 81.2% of yield were obtained at a substrate feeding rate of 0.08h$^{-1}$ under the optimum conditions with carrier volume of 55% and aeration rate of 3 vvm.

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SPECTRAL ANALYSIS OF THE INTEGRAL OPERATOR ARISING FROM THE BEAM DEFLECTION PROBLEM ON ELASTIC FOUNDATION I: POSITIVENESS AND CONTRACTIVENESS

  • Choi, Sung-Woo
    • Journal of applied mathematics & informatics
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    • 제30권1_2호
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    • pp.27-47
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    • 2012
  • It has become apparent from the recent work by Choi et al. [3] on the nonlinear beam deflection problem, that analysis of the integral operator $\mathcal{K}$ arising from the beam deflection equation on linear elastic foundation is important. Motivated by this observation, we perform investigations on the eigenstructure of the linear integral operator $\mathcal{K}_l$ which is a restriction of $\mathcal{K}$ on the finite interval [$-l,l$]. We derive a linear fourth-order boundary value problem which is a necessary and sufficient condition for being an eigenfunction of $\mathcal{K}_l$. Using this equivalent condition, we show that all the nontrivial eigenvalues of $\mathcal{K}l$ are in the interval (0, 1/$k$), where $k$ is the spring constant of the given elastic foundation. This implies that, as a linear operator from $L^2[-l,l]$ to $L^2[-l,l]$, $\mathcal{K}_l$ is positive and contractive in dimension-free context.

Weibull-3 및 Wakeby 분포모형의 L-모멘트법에 의한 설계갈수량 비교분석 (Comparative Analysis of Deisgn Low Flow by L-moment in the Weibull-3 and Wakeby distributions)

  • 이순혁
    • 한국농공학회지
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    • 제42권3호
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    • pp.45-55
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    • 2000
  • This study was carried out to derive optimal design low flows bythe Weibull-3 and Wakeby distributions for the partial consecutive duration series at seven watersheds along Han. nagdong, Geum Yeongsan and Seomjin river systems. L-coefficient of variation L-skewness and L-kurtosis were calculated by the L-moment ratio respectively. Parameters were estimated by the method of L-Moments with consecutive duration. Design low flows obtained by method of L-Moments using with consecutive duration, Design low flows obtained by method of L-Moments using different methods for plotting positions formulas in the Weibull-3 and Wakeby distributions were compared by the Root Mean Square Errors(RMSE). It has shown that design low flows derived by the method of L-moments using Weivull plotting position formula in Wakeby distribution were much closer to those of the observed data in comparison with those obtained by the methods of L-moments with the different formulas for plotting positions in Weibull-3 distribution from the viewpoint of Root Mean Square Errors.

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Synthesis of 2',3'-Dideoxyisoguanosine from Guanosine

  • Kim, Sung-Han;Lee, Sang-Jun;Sun, Won-Suck;Oh, Sung-Wook;Kim, Jung-Han
    • Archives of Pharmacal Research
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    • 제22권6호
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    • pp.619-623
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    • 1999
  • $2^{l},3^{l}$-dideoxyisoguanosine was synthesized from guanosine via intermediate 6-[(4-methyl-phenyl)thio]-2-oxo-9-($2^{l},3^{l},5^{l}$-tri-O-acetyl-$\beta$-D-ribofuranosyl)-2,3-dihydropurine (4). The 2-oxo, 6-amino and $5^{l}$-hydroxy triprotected isoguanosine derivative was utilized to reduce high polarity and promote poor solubility of intermediates. The protecting groups for oxo and 6-amino were easily removed in reduction of olefin in ribose without additional reaction steps.$2^{l},3^{l}$-Vicinal diol in ribose sugar moiety was transformed to olefin with Bu3SnH by radical reaction via bisxanthate. Removing $5^{l}$-O-TBDMS protecting group gave final product, $2^{l},3^{l}$-dideoxyisoguanosine (12) in a 10% overall yield.

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Leptospira 속균(屬菌)에 대한 한우(韓牛) 및 유우(乳牛)의 혈청항체조사(血淸抗體調査) (Serological Survey of Leptospiral Antibody in Dairy and Korean Native Cattle)

  • 최원필;이희석
    • 대한수의학회지
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    • 제25권1호
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    • pp.49-51
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    • 1985
  • A serological survey for antibodies to Leptospira (L.) interrogans in dairy and Korean native cattle in Gyeongbuk area was performed using 6 different living antigens, which were L. icterohaemorrhagiae(RGA), L. canicola(Hond Utrecht IV), L. autumnalis(Akiyami A), L. australis(Ballico), L. pomona(Pomona) and L. hebdomadis(Hebdomadis), by microscopic agglutination test. In the microscopic agglutination test, greater than partial agglutination at a serum dilution of 1:300 or over was recorded as positive. In the dairy cattle(Holstein), four(4.7%) of 86 sera from 13 dairy farms were positive for L. canicola and L. pomona antibodies. In the Korean native cattle, four(3.2%) of 124 sera from the slaughter house in Taegu city were positive for L. canicola, L. icterohaemorrhagiae and L. pomona antibodies. Among the positive sera, L, canicola was dominated in this experiment.

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L-Ascorbic Acid의 생체분해 (A Possible Enzymatic Catabolism of L-Ascorbic Acid via $\alpha$-Ketoaldehydes)

  • 강사욱
    • 미생물학회지
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    • 제23권4호
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    • pp.302-308
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    • 1985
  • L-Ascorbic aciddm ltodcp 산화분해과정중 ${\alpha}$-ketoaldehyde의 한 종류인 3,4,5-trihydroxy-2-keto-L-valeral-dehyde(L-xylosone)가 형성된다는 사실을 핵자기공명스펙트럼분석법으로 확인하였다. 이 물질은 glyoxalase system에 의해 L-xylonic acid로 변환되고 계속해서 L-erythroascorbic acid로 산화된다. 이러한 근거 위에서 vitamin C의 분해과정이 vitamic C 이외의 두종류의 ${\gamma}$-lactones-과 3종류의 ${\alpha}$-ketoaldehydes로 구성된 분해경로를 갖는다는 사실을 제안하였다.

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L2-tree를 이용한 효율적인 빈발항목 집합 탐사 (An Efficient Algorithm for mining frequent itemsets using L2-tree)

  • 박인창;장중혁;이원석
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (1)
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    • pp.259-261
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    • 2002
  • 데이터마이닝 분야에서 빈발항목집합 탐사에 관한 연구는 활발히 진행되어 왔지만 여전히 많은 메모리 공간과 시간을 필요로 한다. 특히 apriori 알고리즘에 기반한 방법들은 긴 패턴이 생성될수록 지수적으로 시간과 공간이 증가한다. 최근에 발표된 fp-growth는 일반적인 데이터 집합에서 우수한 성능을 보이나 희소 데이터 집합에서 효율적인 성능을 보여주지 못한다. 본 논문에서는 길이가 2인 빈발항목집합 L2에 기반한 L2-tree 구조를 제안한다. 또한 L2-tree에서 빈발항목집합을 탐사하는 L2-traverse 알고리즘을 제안한다. L2-tree는 L2를 기반으로 하기 때문에 L2가 상대적으로 적은 희소 데이터 집합 환경에서 적은 메모리 공간을 사용하게 된다. L2-traverse 알고리즘은 별도의 추출 데이터베이스를 생성하는 FP-growth와 달리 단순히 L2-tree를 오직 한번의 깊이 우선 탐사를 통해 빈발항목집합을 찾는다. 최적화 기법으로써 길이가 3인 빈발항목집합 L3가 되지 않는 L2 패턴들을 미리 제거하는 방법으로 C3-traverse 알고리즘을 제안하며 실험을 통해 기존 알고리즘과 비교 검증한다.

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옥상녹화 식재지반이 토양수분과 순비기나무의 생육에 미치는 영향 (Effects of Planting Soil on the Soil Moisture and the Growth of Vitex rotundifolia for Green Roof)

  • 박준석;박지혜;주진희;윤용한
    • 한국조경학회지
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    • 제38권3호
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    • pp.98-106
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    • 2010
  • 본 연구는 옥상녹화 생태면적률 기준을 효과적으로 시행하기 위해, 식재지반이 토양수분과 순비기나무의 생육 특성에 미치는 영향을 살펴보고자 수행하였다. $500{\times}500{\times}300mm$의 실험구에 토심 15cm와 25cm로 대별하였으며, 배합비율에 따라 $S_10$, $L_10$, $S_7L_3$, $S_5L_5$, $P_7P_1L_2$, $P_6P_2L_2$, $P_5P_3L_2$, $P_4P_4L_2$ 등 총 8가지로 하였다. 본 연구는 2006년 4월에서 9월까지 약 5개월간 진행되었으며, 그 결과는 다음과 같다. 옥상녹화 식재기반에 따른 토양수분함량은 점점 감소하는 경향을 보이다가 강우 시 상승한 반면, $S_10$, $S_7L_3$, $S_5L_5$ 실험구의 경우 수분함량이 급격히 떨어지는 경향을 나타내었다. 이에 비해 피트모스와 펄라이트가 포함된 $P_7P_1L_2$, $P_6P_2L_2$, $P_5P_3L_2$, $P_4P_4L_2$에서는 완만하게 감소하여 저관리형 옥상녹화에 보수성이 높은 토양개량제 사용은 불가피할 것으로 판단된다. 순비기나무의 생육실험 결과, $P_6P_2L_2$, $P_5P_3L_2$, $P_4P_4L_2$ 실험구의 경우 생육이 양호하였다. $S_{10}$은 다른 실험구에 비해 미비한 성장을 보였으며, 이것은 낮은 토양수분함량과 유기물부족이 원인으로 작용한 것으로 본다. $L_{10}$ 실험구는 토양수분함량 및 유기물은 풍부한데도 불구하고 낮은 성장량을 보인 것은 유기질비료의 낮은 토양산도와 과잉 양이온함량에 의한 것으로 판단된다. 토심 15cm 실험구와 25cm 실험구를 비교해 보았을 때, 확연한 차이는 없었으나 토심 25cm 실험구에서 좀 더 원활한 생육을 보였다. 하지만 토심 15cm 실험구의 14일 무관수에서도 순비기나무가 고사하지 않고 생육 가능했던 점과 P6P2L2 이상의 피트모스 배합비에서 왕성한 생육이 이루어진 점을 미루어 볼 때, 저관리에 적합한 토양배합비는 인공토가 포함된 $P_6P_2L_2$, $P_5P_3L_2$, $P_4P_4L_2$로 파악할 수 있었다.