• Korean Chemical Engineering Research
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• 제49권5호
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• pp.582-587
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• 2011

점성액체 기포탑에서 기포, wake 및 연속액상들의 체류량 특성을 고찰하였다. 기포탑의 직경(0.051, 0.076, 0.102 and 0.152 m ID), 기체 유속(0.02~0.16 m/s) 그리고 연속액상의 점도(0.001~0.050 $Pa{\cdot}s$)가 기포, wake 및 연속액상의 체류량에 미치는 영향을 검토하였다. 기포, wake 그리고 연속액상들은 이중 전기 저항탐침방법에 의하여 성공적으로 구별할 수 있었다. 압축된 여과공기와 물 또는 CMC 수용액을 각각 기체와 연속액상으로 사용하였다. 기포탑에서 기포와 wake 상들을 연속적으로 검침하기위해 자료수집장치(DT 2805 Lab Card)와 컴퓨터를 사용하였다. 탐침 써키트로부터 수집된 아날로그 자료는 디지털 자료로 변환되었으며, 이들 자료를 이용하여 기포탑에서 상승하는 단일기포 뿐만이 아니라 다중기포들의 후면에서 wake 상을 검침할 수 있었다. 기포와 wake 상의 체류량은 각각 기포탑의 직경과 연속액상의 점도가 증가함에 따라 감소하였으나 연속액상의 체류량은 증가하였다. 그러나, 기포와 wake의 체류량은 각각 기체 유속이 증가함에 따라 증가한 반면 연속액상의 체류량은 감소하였다. wake 상 체류량에 대한 기포 체류량의 비율은 기포탑의 직경 또는 기체의 유속이 증가함에 따라 감소한 반면 연속액상의 점도가 증가함에 점성액체 기포탑에서 기포, wake 그리고 연속액상의 체류량은 본 연구의 실험범위에서 다음과 같은 실험변수의 상관식으로 나타낼 수 있었다. ${\varepsilon}_B=0.043D^{-0.18}U_G^{0.56}{\mu}_L^{-0.13}$, ${\varepsilon}_W=0.003D^{-0.85}U_G^{0.46}{\mu}_L^{-0.10}$, ${\varepsilon}_C=1.179D^{0.09}U_G^{-0.13}{\mu}_L^{0.04}$.

• Food Science and Biotechnology
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• 제16권5호
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• pp.747-752
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• 2007

This study was carried out to identify and quantify the flavonoids from 6 different plant parts of Allium victorialis var. platyphyllum (AVP), including the flower, leaf, root, stem, flower stalk, and flower seed, using liquid chromatography/ mass spectrometry. Two major flavonoids were structurally identified as quercetin (3,5,7,3'4,'-pentahydroxyflavone) and kaempferol (3,5,7,4'-tetrahydroxyflavone) at contents of 11.8-25.8 and $6.0-64.4\;{\mu}g/mL$, respectively. In particular, the flower and root plant parts contained the highest amounts of quercetin and kaempferol compared to the other parts. We also assessed the recovery effects of each plant-part extract of AVP on gap junctional intercellular communication (GJIC) in WB-F344 cells by the scrape-loading and dye transfer (SL/DT) method. According to the results, GJIC was reduced by approximately 70.2% ($62.3{\pm}12.5$ cells) compared to the control ($209{\pm}9.5$ cells, 100%) when 12-O-tetradecanoylphorbol-13-acetate (TPA) was treated alone in the WB-F344 rat liver epithelial cells. However, the stem extract (0.2 mg/mL) restored GJIC to basal levels (92%, $204{\pm}2.3$ cells, p<0.01) and the flower extract (0.2 mg/mL) stimulated GJIC to 82.5% ($172.6{\pm}8.3$ cells, p<0.05), when applied together with the TPA.

• 한국임상수의학회지
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• 제24권4호
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• pp.509-513
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• 2007

혈청검사항목의 해석기준으로 사용하는 참고범위는 측정 장비와 병원마다 차이를 보이기 때문에 병원 간 정보를 교환하고 해석하는데 어려움이 많다. 또한 동일한 병원에서도 내원한 환자의 특성을 고려하여 참고범위를 재설정하는 것이 일반모집단의 특성을 제대로 반영한다. 본 연구에서는 강원대학교 수의학부대학 동물병원에서 설정한 혈청화학 검사 항목의 참고범위를 재평가하기 위하여 2005-2006년 동안 본원에 내원한 임상적으로 건강한 개 100두(1-8세, 체중 2.2-5.8 kg)의 혈청검사 일부 항목을 모수 및 비모수적 bootstrap 모의시험으로 분석하였다. 평가항목은 BUN(mg/dl), cholesterol(mg/dl), calcium(mg/dl), aspartate aminotransferase(AST, U/L), alanine aminotransferase(ALT, U/L), alkaline phosphatase(ALP, U/L) 및 total protein(g/dl)으로 Ektachem DT 60 분석기(Johnson & Johnson)로 측정하였다. 칼슘을 제외한 모든 항목이 왜곡이 매우 심한 분포를 보였으며 특히 혈청 효소항목의 outlier는 전체 자료의 5-9%, 기타 항목은 1-2%를 보였다. 각 항목의 분포에 상관없이 모수적 방법에 비하여 비모수적 방법으로 추정한 참고범위가 임상적으로 유용하였으며 추정된 참고범위는 BUN 14.7(7.0-24.2), cholesterol 227.3(120.7-480.8), calcium 10.9(8.1-12.5), AST 25.4(11.8-66.6), ALT 25.5(11.7-68.9), ALP 87.7(31.1-240.8), and total protein 6.8(5.6-8.2)로 나타났다. 이러한 결과는 모집단의 특성을 고려하여 참고범위를 재설정하는데 비모수적 모의시험이 매우 유용하며 특히 측정항목의 분포에 무관하게 사용할 수 있는 장점이 있는 것으로 사료된다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.111-111
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• 2009

In this work, we discuss simulation of surface acoustic wave device using Comsol Multiphysics. The structure SAW device based on piezoelectric thin film aluminum-nitride (AlN) on silicon was simulated. Some parameters of SAW device such as surface velocity, displacement of piezoelectric thin film were evaluated by software. Many modes and shapes of wave are also discussed in this paper. For evaluation physical parameters of AlN piezoelectric layer, the SAW resonator was modeled and simulation results were also compared with experiment results. we simulated arid evaluated the surface Rayleigh wave of AlN thin film on silicon substrate. Results simulation and experiment showed the surface velocity of AlN thin film was about 5200 m/s and shape of surface wave was also displayed. This paper has also proposed as method to study SAW characteristic of piezoelectric thin film and found out measurement values accurately of film such as stiffness matrix, piezoelectric matrix. These values are very important in calculation and design SAW device or MEMS device based on AlN piezoelectric layer.

• 대한기계학회논문집A
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• 제24권12호
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• pp.3088-3095
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• 2000

Creep-fatigue crack growth behavior was experimentally measured particularly when a crack was located in the heat affected region of lCr-5Mo steel. Load hold times of the tests for trapezoidal fatigue waveshapes were varied among 0, 30, 300 and 3,600 seconds. Time-dependent crack growth rates were characterized by the $C_r$parameter. It was found that the crack growth rates were the highest when the crack path was located along the fine-grained heat affected zone(FGHAZ). Cracks located in other heat affected regions had a tendency to change the crack path eventually to FGHAZ. Creep-fatigue crack growth law of the studied case is suggested in terms of (da/dt)$_{avg}$ vs. ($C_t$)$_{avg}$ for residual life assessment.

• Journal of Advanced Marine Engineering and Technology
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• 제21권4호
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• pp.393-403
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• 1997

In this paper, we proposed an optimal identification method of identifying the membership func¬tions and the fuzzy rules for the stabilization controller of the nonlinear system by RVEGA( Real Variable Elitist Genetic Algo rithm l. Although fuzzy logic controllers have been successfully applied to industrial plants, most of them have been relied heavily on expert's empirical knowl¬edge. So it is very difficult to determine the linguistic state space partitions and parameters of the membership functions and to extract the control rules. Most of conventional approaches have the drastic defects of trapping to a local minima. However, the proposed RVEGA which is similiar to the processes of natural evolution can optimize simulta¬neously the fuzzy rules and the parameters of membership functions. The validity of the RVEGA - based fuzzy controller was proved through applications to the stabi¬lization problems of an inverted pendulum system with highly nonlinear dynamics. The proposed RVEGA - based fuzzy controller has a swing -. up control mode(swing - up controller) and a stabi¬lization one(stabilization controller), moves a pendulum in an initial stable equilibrium point and a cart in an arbitrary position, to an unstable equilibrium point and a center of the rail. The stabi¬lization controller is composed of a hierarchical fuzzy inference structure; that is, the lower level inference for the virtual equilibrium point and the higher level one for position control of the cart according to the firstly inferred virtual equilibrium point. The experimental apparatus was imple¬mented by a DT -- 2801 board with AID, D/A converters and a PC - 586 microprocessor.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 전력전자학술대회 논문집
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• pp.464-466
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• 2001

The advantage of the squirrel cage induction motor is the brushless rotor. This advantage for operation and maintenance turns out to be a disadvantage for the detection of the cage rotor bar and endring defects, which means that the detection of cage faults is due to the measurement and analysis of only the stator input signals. The monitoring task in an inverter drive is complicated mainly because the voltage and current waveforms are nonsinusoidal and the high dv/dt values from fast switching inverterd distort the measurements. in this paper, we are going to discuss the detection method of broken rotor bar of squirrel cage induction motor by the motor current signal analysis(MCSA).

• 한국군사과학기술학회지
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• 제20권4호
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• pp.536-542
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• 2017

In this paper, authors described on localization development's results about an electric igniter in thermal battery with a pyrotechnic heat sources. Especially, the development test and evaluation(DT&E) process and the methods in the developments of the electric igniter which is parts of a domestic thermal battery on K-PSAM was in charge of government and developed for defense of a local areas in Korea. We have proposed a process of design and manufacture on the electric igniter. Finally, we verified a quality and a reliability of the electric igniter from test results by Fisher-Snedecor's law and over 99.5 %(C.L. 95 %) for K-PSAM.

• Kyungpook Mathematical Journal
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• 제28권2호
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• pp.129-139
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• 1988

Let $T^{\alpha}_{\lambda}$(p, A, B) denote the class of functions $$f(z)=z^p-{\sum\limits^{\infty}_{k=1}}{\mid}a_{p+k}{\mid}z^{p+k}$$ which are regular and p valent in the unit disc U = {z: |z| <1} and satisfying the condition $\left|{\frac{{e^{ia}}\{{\frac{f^{\prime}(z)}{z^{p-1}}-p}\}}{(A-B){\lambda}p{\cos}{\alpha}-Be^{i{\alpha}}\{\frac{f^{\prime}(z)}{z^{p-1}}-p\}}}\right|$<1, $z{\in}U$, where 0<${\lambda}{\leq}1$, $-\frac{\pi}{2}$<${\alpha}$<$\frac{\pi}{2}$, $-1{\leq}A$<$B{\leq}1$, 0<$B{\leq}1$ and $p{\in}N=\{1,2,3,{\cdots}\}$. In this paper, we obtain sharp results concerning coefficient estimates, distortion theorem and radius of convexity for the class $T^{\alpha}_{\lambda}$(p, A, B). It is further shown that the class $T^{\alpha}_{\lambda}$(p, A, B) is closed under "arithmetic mean" and "convex linear combinations". We also obtain class preserving integral operators of the form $F(z)=\frac{p+c}{z^c}{\int^z_0t^{c-1}}f(t)dt$, c>-p, for the class $T^{\alpha}_{\lambda}$(p, A, B). Conversely when $F(z){\in}T^{\alpha}_{\lambda}$(p, A, B), radius of p valence of f(z) has also determined.

• Plant Breeding and Biotechnology
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• 제6권4호
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• pp.444-453
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• 2018

The rice bran oil contained in brown rice is composed of highly valued ingredient. Improving the content of unsaturated fatty acids in rice seed, such as oleic acid, linoleic acid, and ${\alpha}$-linolenic acid, would provide more benefit to human health. Fatty acid content is quantitative trait controlled by multiple genes. We have utilized high-density SNP data from highly advanced breeding populations to identify QTLs for fatty acid contents in brown rice. Here, we identified 51 major QTLs (M-QTLs) and 25 epistatic QTLs (EpQTLs) related to eleven fatty acid contents. Eight and four M-QTLs were pleiotropically associated with the content of different fatty acids in MT-RILs and DT-RILs, respectively. Total effect of M-QTLs for palmitic acid (16:0), oleic acid (18:1), and linoleic acid (18:2), could explain phenotypic variations of 36.7%, 63.7%, and 41% in MT-RILs, respectively. Alpha-linolenic acid which is important for a human's health could be explained phenotypic variation of 15.7% by six M-QTLs. These QTLs identified in this study can be used to improve nutritious content in rice breeding programs.