• Title/Summary/Keyword: C.E.R

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A Study on the Prediction of the Permanent Wilting Point in Woody Plant by Cambial Electrical Resistance (목본식물의 형성층 전기저항에 의한 영구위조점 예측에 관한 연구)

  • 김민수
    • Journal of the Korean Institute of Landscape Architecture
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    • v.22 no.4
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    • pp.75-80
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    • 1995
  • It is important to estimate the possibility of recovery in physiologically damaged woody plant. It is suggested that C.E.R(cambial electrical resistance) might be a useful method to predict the permanent wilting point. D/A and A/D converter can be used to measure the C.E.R and it took only 10-20 msec for a measurement and the values were stable during this study. A computer could be used for the continual measurement of C.E.R. There were very big daily changes of C.E.R. was changed according to the changes of indoor temperature, but the phase was slightly different. It is reasoned that daily changes in C.E.R. is induced by the changes of water potential and cambial thickness. It was difficult to detect the changes of C.E.R. caused by changes in soil moisture under high soil water potential. Under low soil water potential, the changes in soil moisture under high soil water potential. Under low soil water potential, the changes of C.E.R. can be detected. After wilting, C.E.R. is increased very rapidly. When C.E.R. is not decreased by watering, it will be permanent wilting point. But it takes several days to confirm the permanent wilting point. To predict the possibility of recovery from wilting, the values of C.E.R. have no meaning. But the changes of C.E.R. are significant. Therefore we can predict the permant wilting point in woody plant by monitoring the change of C.E.R. by the computer.

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Routley-Meyer Semantics for E-R, Ee-R, Eec-R

  • Yang, Eun-Suk
    • Korean Journal of Logic
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    • v.6 no.1
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    • pp.19-32
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    • 2003
  • In this paper we investigate the relevance logic E-R of the Entailment E without the reductio (R), and its extensions Ee-R, Eec-R: Ee-R is the E-R with the expansion (e) and Eec-R the Ee-R with the chain (c). We give completeness for each E-R, Ee-R, and Eec-R by using Routley-Meyer semantics.

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[r, s, t; f]-COLORING OF GRAPHS

  • Yu, Yong;Liu, Guizhen
    • Journal of the Korean Mathematical Society
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    • v.48 no.1
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    • pp.105-115
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    • 2011
  • Let f be a function which assigns a positive integer f(v) to each vertex v $\in$ V (G), let r, s and t be non-negative integers. An f-coloring of G is an edge-coloring of G such that each vertex v $\in$ V (G) has at most f(v) incident edges colored with the same color. The minimum number of colors needed to f-color G is called the f-chromatic index of G and denoted by ${\chi}'_f$(G). An [r, s, t; f]-coloring of a graph G is a mapping c from V(G) $\bigcup$ E(G) to the color set C = {0, 1, $\ldots$; k - 1} such that |c($v_i$) - c($v_j$ )| $\geq$ r for every two adjacent vertices $v_i$ and $v_j$, |c($e_i$ - c($e_j$)| $\geq$ s and ${\alpha}(v_i)$ $\leq$ f($v_i$) for all $v_i$ $\in$ V (G), ${\alpha}$ $\in$ C where ${\alpha}(v_i)$ denotes the number of ${\alpha}$-edges incident with the vertex $v_i$ and $e_i$, $e_j$ are edges which are incident with $v_i$ but colored with different colors, |c($e_i$)-c($v_j$)| $\geq$ t for all pairs of incident vertices and edges. The minimum k such that G has an [r, s, t; f]-coloring with k colors is defined as the [r, s, t; f]-chromatic number and denoted by ${\chi}_{r,s,t;f}$ (G). In this paper, we present some general bounds for [r, s, t; f]-coloring firstly. After that, we obtain some important properties under the restriction min{r, s, t} = 0 or min{r, s, t} = 1. Finally, we present some problems for further research.

Impact of Remanent Polarization and Coercive Field on Threshold Voltage and Drain-Induced Barrier Lowering in NCFET (negative capacitance FET) (NCFET (negative capacitance FET)에서 잔류분극과 항전계가 문턱전압과 드레인 유도장벽 감소에 미치는 영향)

  • Hakkee Jung
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.37 no.1
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    • pp.48-55
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    • 2024
  • The changes in threshold voltage and DIBL were investigated for changes in remanent polarization Pr and coercive field Ec, which determine the characteristics of the P-E hysteresis curve of ferroelectric in NCFET (negative capacitance FET). The threshold voltage and DIBL (drain-induced barrier lowering) were observed for a junctionless double gate MOSFET using a gate oxide structure of MFMIS (metal-ferroelectric-metal-insulator-semiconductor). To obtain the threshold voltage, series-type potential distribution and second derivative method were used. As a result, it can be seen that the threshold voltage increases when Pr decreases and Ec increases, and the threshold voltage is also maintained constant when the Pr/Ec is constant. However, as the drain voltage increases, the threshold voltage changes significantly according to Pr/Ec, so the DIBL greatly changes for Pr/Ec. In other words, when Pr/Ec=15 pF/cm, DIBL showed a negative value regardless of the channel length under the conditions of ferroelectric thickness of 10 nm and SiO2 thickness of 1 nm. The DIBL value was in the negative or positive range for the channel length when the Pr/Ec is 25 pF/cm or more under the same conditions, so the condition of DIBL=0 could be obtained. As such, the optimal condition to reduce short channel effects can be obtained since the threshold voltage and DIBL can be adjusted according to the device dimension of NCFET and the Pr and Ec of ferroelectric.

The Relation of the Elevated Plasma Lipid Levels to Plasma Vitamin E Status and Activities of Erythrocyte Glutathione Perosicase in Smokers (흡연인들에서 증가된 혈장지질 농도가 비타민 E 영양상태와 글루타티온 과산화효 활성에 미치는 영향)

  • 윤군애
    • Journal of Nutrition and Health
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    • v.31 no.8
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    • pp.1254-1262
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    • 1998
  • This study has done to investigate the relationship between the icreased lipid oncentration caused by smoking and plama levels of vitamin A and vitamin E, antiodative enzyme activity, and lipid peroxidation , in 52 male smokers and 32 non-smokers, Dietary vitamin A and vitamin E intake was imilar in both smokers and non-smokers. Absolute plasma concentrations of vitamin A and vitamin E were not significantly different between two groups, whereas vitamin E/cholesterol ration in plasma was low or in smokers than in that of non-smokers(p<0.05). It was considered that this lowered effect was due to the elevated plasma lipid concentration rather than oxidant stress derived from smoking, in view of the fact that smokers had higher cholesterol (15.2%) adn LDL-C(26.6%) levels than non-smokers. In non-smokers, plasma thiobarbiturin acid reactive substances(TBARS) conrrelated positively with total cholesterol(r=0.63466, p<0.001), LDL-C level(r=0.57166, p<0.01) , and LDL-C/HDL-C ratio(r=0.45926, p<0.05) . Activities of glutathione perosidase(GSH-Px) , superoside dismutase(SOD), and catalse made no difference in both groups. However, it was observed in non-smokers that GSH-Px activity had negative correlations with total cholesterol(r=-0.67293, p<0.001), LDL-C level(r=-0.62878, p<0.001), and LDL-C/HDL-C ratio (r=-0.58824, p<0.01), indicating that there was a dependent relationship between lipid perosidation and plasma lipid level. The smokers also showed negative correlations for GSH-Px activity with total cholesterol (r=-0.29946, p<0.05) and LDL-c level (r=0.45914, p<0.001), and LDL-C/HDL-c ratio(r=-0.35438, p<0.05). It seemed that the lipid that the lipid level elevated by sustaines smoking resulted in reducing vitamin E/cholesterol ratio and proportion of antioxidant to oxidant load, and then GSH-Px activity, with insufficient removal of free radicals(TBARS 2.43$\pm$0.51 and 1.81$\pm$0.15nmol/ml in smokers and non-smokers, respectively). These findings suggest that higher plasma lipid levels may play a more important role in perturbing the antioxidant defense system including vitamin E status and GSH-Px activity, at least in circumstances that increase lipid concentration . In addition, in exposure to free radicals like those in cigarette smoke. In those cases the ratio of vitamin E/lipid in plasma can be a more indicator of vitamin E status than plasma levels of vitamin E alone.

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A Study on Nuclear Information Management System Utilizing Microcomputer (마이크로 컴퓨터를 이용한 원자력 분야 정보 관리 시스템 개발)

  • 김규선;김태승
    • Journal of the Korean Society for information Management
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    • v.6 no.1
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    • pp.15-36
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    • 1989
  • The r a p i d i n c r e a s e o f microcomputer technology has r e s u l t e d i n t h e broad a p p l i c a t i o n t o various f i e l d s . The purpose of t h l s paper 1s to design a computerized r e t r i e v a l system f o r nuclear information m a t e r i a l s using a microcomputer.

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Volatile Flavor Components in Various Varieties of Peach(Prunus persica L.) Cultivated in Korea (국내산 복숭아의 품종별 휘발성 향기성분)

  • 박은령;조정옥;김경수
    • Food Science and Preservation
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    • v.6 no.2
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    • pp.206-215
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    • 1999
  • Volatile flavor components in five varieties, Bekdo, Chundo, Yumung, Daegubo and Hwangdo, of peach (Prunus persica L.) were extracted by SDE (Simultaneous steam distillation and extraction) method using the mixture of n-pentane and diethylether(1:1, v/v) as an extract solvent. Analysis of the concentrate by capillary gas chromatography and gas chromatography-mass spectrometry led to the identification of 83, 85, 70, 74 and 66 components in Bekdo, Chundo, Yumung, Daegubo and Hwangdo, respectively. Aroma patterns (29 alcohols, 27 ketones, 18 aldehydes, 9 esters, 5 ethers, 3 acids, 6 terpene and derivatives, and 26 miscellaneous) were identified and quantified in five cultivars. Ethyl acetate, hexanal, o-xylene, (E)-2-hexenal, hexanol, (E)-2-hexen-1-ol, benzaldehyde, r-decalactone and r-dodecalactone were the main components in each samples, though there were several differences in composition of volatile components. Beside C$\_$6/ compounds, a series of saturated and unsaturated r- and $\delta$-lactones ranging from chain length C$\_$6/ to C$\_$l2/, with concentration maxima for r-decalactone and r-dodecalactone, were a major class of constituents. Lactones and peroxidation products of unsaturated fatty acid (i.e. C$\_$6/ aldehydes and alcohols) were major constituents of the extract.

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