• Title/Summary/Keyword: L지수

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Origin of B, Br and Sr in Groundwater from Bukahn-myeon, Yeongcheon, Gyeongbuk Province, with Emphasis on Hydrochemistry (지하수의 수질화학적 특징과 붕소, 브롬, 스트론튬 성인에 대한 고찰)

  • Choo, Chang-Oh;Lee, Jin-Kook;Lee, Chang-Joo;Park, Ki-Ho;Jeong, Gyo-Cheol
    • The Journal of Engineering Geology
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    • v.19 no.2
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    • pp.235-250
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    • 2009
  • Environmental elements such as B, Br, and Sr in groundwater from Bukahn-myeon, Yeongcheon, Gyeongbuk Province, were investigated in order to know their origin with emphasis on hydrochemistry. pH ranges from 7.37 to 8.39. B content is 0.41${\sim}$4.62 mg/L with an average 1.74 mg/L and Br content is 0${\sim}$3.24 mg/L with an average 2.22 mg/L, and Sr content is 0.93${\sim}$8.64 mg/L with an average 2.76 mg/L. The water types plotted by the Piper diagram are different but mostly $Ca-HCO_3$. Some constituents contributing to EC are Na, $SO_4$, Cl with high determinative coefficients($R^2$) of 0.85, 0.70, 0.90, respectively. The coefficients($R^2$) of Cl to Na, K, $SO_4$ are 0.54, 0.68, 0.53, respectively. It should be noted that there are high cocfficients($R^2$) of B-Sr and $Sr-SO_4$ with 0.65, 0.64, respectively. The Cl/Br ratios are 5.21${\sim}$30.70 due to significant depletion of Cl. The $SO_4/Cl$ ratios are 1.32${\sim}$27.24 with an average of 5.92, ascribed to abundant introduction of $SO_4$ or significant depletion of Cl. Chemical speciation calculated shows that B exists mostly as $H_3BO_3$ with less $H_2BO^-_3$ and Br exists as only $Br^-$. Sr exists mostly as $Sr^2$ with less $SO_4$. Saturation index represents that goundwater is supersaturated with respect to barite, kaolinite, illite, K-mica, and smectite while it is slightly undersaturated with respect to silica, gypsum, anhydrite, talc, chrysotile, feldspar, kaolinite, illite, K-mica, and smectite. The saturation index of celestine is -2.23${\sim}$-0.13 indicating more Sr can be incorporated into groundwater. Groundwater is still much undersaturated to halite. It is likely that the origin of S and Sr was related to the Yucheon volcanic rocks. Br might be originated from the local geological features with introduction of anthropogenic matters.

Correlation between Internal and External Egg Quality Indicators in the Early Phase of Hy-Line Brown Laying Hens

  • Jang, Eunhye
    • Korean Journal of Poultry Science
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    • v.49 no.2
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    • pp.53-60
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    • 2022
  • This study investigated correlations between egg quality indicators to identify external egg quality traits to predict internal egg quality using non-destructive and convenient measurements. Thirteen indicators, including Haugh unit, albumen height, eggshell breaking strength, eggshell thickness, eggshell color (CIE L*, CIE a*, CIE b*), and reflectivity value, egg weight, egg length, egg width, shape index, and yolk color, were investigated. A total of 180 brown eggs were obtained from one 27-week-old flock of Hy-line brown-laying hens raised in a cage system. Correlations were evaluated using Pearson's correlation coefficient (r). The results showed strong correlations between Haugh unit and albumen height, eggshell color CIE L* and reflectivity, egg weight and width, egg weight and length, eggshell color CIE L* and CIE a*, eggshell color CIE a* and reflectivity, and shape index and egg length (P<0.001). Moderate correlations were observed between eggshell breaking strength and eggshell thickness, eggshell color CIE a* and CIE b*, and shape index and egg width (P<0.001). Eggshell color CIE L* was correlated with eggshell breaking strength (P<0.01), and eggshell color CIE a* was correlated with Haugh unit, albumen height (P<0.01), and eggshell breaking strength (P<0.001). The present study showed significant correlations between eggshell color and other quality indicators. Thus, this study suggests that eggshell colors based on reflectiveness and the CIE L*a*b* value can be used to estimate the Haugh unit, albumen height, eggshell breaking strength, and thickness.

A Study on Combustion Characteristics of Hybrid Rocket with the Variation of L/D Ratio (하이브리드 로켓의 L/D 비 변화에 따른 연소특성 연구)

  • Kim Soo-Jong;Kim Jin-Kon;Lee Seung-Chul;You Woo-Jun;Lee Jung-Pyo
    • Journal of the Korean Society of Propulsion Engineers
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    • v.9 no.4
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    • pp.31-38
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    • 2005
  • In this paper, the combustion characteristics of a hybrid propulsion system were studied with various L/D(length vs diameter) ratio of the single po.1 type solid fuel. Experiments were performed for 2 cases with the fixed grain port diameter and fuel length respectively. For the first case, results show that there are no large variations for regression rates as the L/D ratio changes. And as the L/D ratio increases, the O/F ratio decreases and thrust, characteristic velocity tends to increase. For the second case, there is no large change for O/F ratio, thrust and characteristic velocity as L/D ratio changes. On the other hand, as the L/D ratio decreases, only the regression rate tends to increase. Experimentally, exponent n in $\dot{r}=a{G_0}^n$ was found about 0.5 and then the O/F ratio was shown nearly constant. In the experiment, PE and gas oxygen were used as a fuel and an oxidizer.

The Evaluation of 2-25Cr-lMo Steels Degradation by the Electrochemical Polarization Method (전기화학적 분극특성을 이용한 2.25Cr-lMo 강의 열화도 평가)

  • 김지수;현양기;이재도;오세규
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2001.05a
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    • pp.314-319
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    • 2001
  • Most parts of facilities in domestic petroleum plants and power plants are needed to be abandoned, repaired or replaced, because in Korea they were built in the 1960s and, they have been used under severe conditions and exposed corrosive environments. 2.25Cr- lMo steels have excellent high-temperature mechanical properties. Therefore, the material have been widely used as heat exchanger tubes, boiler headers and its tubes in such industries. But, those microstructural evolutions in high temperature such as precipitation and carbide coarsening give a reason to degrade the material. Especially, in case of this material, carbides induced embrittlement(CIE) is the primary reason for degrading mechanical properties at over 50$0^{\circ}C$. In this paper, we introduce a electrochemical polarization method for detecting CIE quantitatively.

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Performance Analysis of MRC Diversity for M-ary QAM Signals in Digital Land Mobile Communications (디지털 육상 이동통신에서 M진 QAM 신호의 최대비 합성 다이버시티 성능분석)

  • Yun, Dong-Won;Lee, Bong-Hwan
    • The KIPS Transactions:PartC
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    • v.8C no.3
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    • pp.359-366
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    • 2001
  • 이 논문에서는 주파수 비선택적 느린 나카가미 m-분포 페이딩 육상 이동통신 채널에서 M 진 QAM 신호에 L-가지의 최대비 합성 다이버시티를 적용하였을 때의 오율성능을 유도하 고 분석한다. 다이버시티 채널의 페이딩 인자가 동일한 경우와 서로 다른 경우에 대하여 각 각 다중가지 다이버시티 시스템을 고려한다. 페이딩 지수 m=1 인 경우 유도된 M진 QAM 신호의 최대비 합성 다이버시티 심볼 오율식은 레일리 페이딩 채널에서의 오류식으로 돌아 간다. 유도된 결과 식들은 L 값에 대하여 신호대 잡음비에 대한 함수로 최대비 합성 다이버 시티 심볼 오율을 나타낸다. L 값을 증가시킬수록 성능 향상을 가져옴을 보여준다. 이 논문 에서 제시된 결과들은 디지털 육상 이동통신에서 QAM 시스템의 성능을 편리하게 셰산하는 데 충분히 일반적이다.

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The Effect of Drilling Patterns and Rock Mass Conditions on Fragmentation and Ground Vibration in Quarry Blasting (천공방식과 암질등급이 파쇄도와 진동수준에 미치는 영향)

  • 정영준;양형식;이상은
    • Explosives and Blasting
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    • v.20 no.1
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    • pp.5-14
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    • 2002
  • 파쇄 암석의 파쇄도는 발파효율을 나타내는 중요 척도로서 적재와 분쇄 작업에 큰 영향을 미친다. 그러나 현장에 쌓여 있는 발파암 더미로부터 파쇄도를 조사한다는 것은 용이한 작업이 아니다. 본 연구에서는 석산 발파에서 가장 중요한 요소인 천공방식과 암질의 변화가 파쇄도와 발파진동에 미치는 영향을 조사하였다. 파쇄 입도에 영향을 미치는 중요한 변수인 천공방식, 암질등급(RMR), 현지 암반의 블록 크기, 발파진동 등의 영향을 파쇄암의 평균입도(MFS)와 상위 5개의 대괴 평균치$(L_5)$로 나타내었다. 연구결과, 파쇄암의 평균입도는 상위 5개의 대괴 평균치와 선형적인 관계를 보였다. 발파방법과 파쇄도 평가 결과 재래식 발파에서는 파쇄도를 예측할 수 없었고 커다란 옥석이 생성되었으나, 벤치발파에서는 평균파쇄암의 크기가 비교적 양호한 파쇄 상태를 유지하였다. 현지 암반 블록 크기는 평균 파쇄암의 크기와 선형적 관계를 나타내었다. RMR값이 커짐에 따라 발파진동 추정식의 진동상수 K와 감쇠지수 n의 절대값과 평균 파쇄암의 크기, 그리고 상위 대괴의 크기는 대체적으로 증가하는 경향을 나타내었고, 진동상수 K와 감쇠지수 n도 증가하는 경향을 보였다.

Design of a Low Noise Amplifier for Wireless LAN (무선 근거리 통신망용 저잡음 증폭기의 설계)

  • 류지열;노석호;박세현
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.6
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    • pp.1158-1165
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    • 2004
  • This paper describes the design of a two stage 1V power supply SiGe Low Noise Amplifier operating at 5.25㎓ for 802.lla wireless LAN application. The achieved performance includes a gain of 17㏈, noise figure of 2.7㏈, reflection coefficient of 15㏈, IIP3 of -5㏈m, and 1-㏈ compression point of -14㏈m. The total power consumption of the circuit was 7㎽ including 0.5㎽ for the bias circuit.

Lasso Regression of RNA-Seq Data based on Bootstrapping for Robust Feature Selection (안정적 유전자 특징 선택을 위한 유전자 발현량 데이터의 부트스트랩 기반 Lasso 회귀 분석)

  • Jo, Jeonghee;Yoon, Sungroh
    • KIISE Transactions on Computing Practices
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    • v.23 no.9
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    • pp.557-563
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    • 2017
  • When large-scale gene expression data are analyzed using lasso regression, the estimation of regression coefficients may be unstable due to the highly correlated expression values between associated genes. This irregularity, in which the coefficients are reduced by L1 regularization, causes difficulty in variable selection. To address this problem, we propose a regression model which exploits the repetitive bootstrapping of gene expression values prior to lasso regression. The genes selected with high frequency were used to build each regression model. Our experimental results show that several genes were consistently selected in all regression models and we verified that these genes were not false positives. We also identified that the sign distribution of the regression coefficients of the selected genes from each model was correlated to the real dependent variables.

Performance Analysis of Diversity Received DS-CDMA/MDPSK Signals in m-distribution and Rician Fading Environments (m-분포 페이딩과 라이시안 페이딩 환경 하에서의 다이버시티 수신된 DS-CDMA / MDPSK 신호의 성능 분석)

  • 이정도;강희조
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.9 no.2
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    • pp.191-198
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    • 1998
  • The error are equation of DC-CDMA/MDPSK signal has been derived in m-distribution and Rician fading channels. Predeteception multipath MRC(Maximal Ratio Combining) diversity technique is employed for improving the bit error rate performance. The suitability of modeling a Rician fading environment by properly chosen m-distribution model is examined. Using the derived equation the error performance has been evaluated and shown in figures as a function of PN code sequence length(N), user number(U), multipath number(P), fading index(m), Rician factor(K), number of diversity branches(L) and ($E_b/N_o$). The results show that the error performance in Rician fading agrees well with that in m-distribution fading as fading becomes weak and as user number(U) increases and as multipath number(P) increases and diversity number(L) increases.

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Weathering Characteristics of Granitic Regolith in Southern part of the Korean peninsula (한반도 남부의 화강암 구릉대 지표피복물의 풍화 특색)

  • KIM, Youngrae;KEE, Keundo;YANG, Jaehyuk
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.4
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    • pp.123-137
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    • 2012
  • Reddish superficial materials in southern area of Korean Peninsula have been defined as lateritic red soil in Korea. In A-CN-K ternary plots, CaO and $Na_2O$ show similar linear distribution along a A-K line to kaolinite profile and laterite in southern Spain and Cameroon, respectively, and it means strong alteration. But $K_2O$ is weak alteration, plotting between muscovite and illite zone. Granitic reddish weathering mantles in study area show bulk distribution in center when plotted in A-CNK-Fm space, in contrast to laterite in Cameroon, plotting linearly in the middle along a A-FM line. Therefore, alteration of reddish saprolites in Southern Korea have not progressed as much as laterite. To define Reddish saprolite in southern Korean Peninsula as a lateritic red soil, more many studies are necessary.