• 한국염색가공학회지
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• 제14권2호
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• pp.40-50
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• 2002

In order to remove the pollutants effectively in the dye wastewater by chemical precipitation process, coagulation arid flocculation test were carried out using several coagulants on various reaction conditions. It was found that the Ferrous sulfate was the most effective coagulant for the removal of disperse dye(B79), and we could get the best result lot the removal of disperse dye(B56) in the aspects of TOC removal efficiency and sludge field. When the Ferrous sulfate dosage was $800mg/\ell$, the sludge settling velocity was very fast>, and the color was effectively removed in the disperse dye(B79) solution. Although the color removal was ineffective when the Alum was used as a coagulant, the sludge field was decreased in comparison with the Ferrous sulfate or the Ferric sulfate was used in the disperse dye(B56) solution. The general color removal effect for the disperse dye(B56 and B79) solutions, the Ferric sulfate was more proper coagulant than the Alum. It was showed that TOC removal was improved 5% and over by the addition of Calcium hydroxide, and $30mg/\ell$ of sludge yield was decreased(B79). When Alum or Ferric sulfate was used as a coagulant, pH condition for most effective color removal was 5 in B56 solution. In case of Ferrous sulfate as a coagulant, most effective pH condition for color removal was 9. When Ferric sulfate or Ferrous sulfate was used as a coagulant, pH condition for most effective color removal was 9 in B79 solution.

• 대한수학회보
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• 제41권3호
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• pp.493-505
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• 2004

We introduce certain local Thomsen condition in a 3-web and prove that it is equivalent to the equation a－(a－b)＝b in its corresponding loop, where we denote the loop operation additively for convenience and simplicity, even though the loop is neither associative nor commutative. Also we interpret such local Thomsen condition using orthogonality of chains in a web.

• 농업생명과학연구
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• 제43권3호
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• pp.27-34
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• 2009

녹차 잎 1.5 g에 증류수 100 mL을 가하여 $75^{\circ}C$에서 5분 동안 추출하여 녹차 음료를 제조하였다. 저장 조건을 달리하여 A 녹차 음료 (빛을 인위적으로 차단하지 않음, 자연 상태의 대기 조건, 비타민 C 무첨가), B 녹차 음료 (빛을 알루미늄 호일로 감싸서 차단함, 질소를 불어넣어 자연 대기를 질소로 치환하였음, 비타민 C 30 mg/100 mL 첨가), C 녹차 음료 (빛을 알루미늄 호일로 감싸서 차단함, 질소를 불어넣어 자연 대기를 질소로 치환하였음, 비타민 C 무첨가)로 구분하여 $4^{\circ}C$에서 28일간 저장한 후, 유용 성분을 분석하였다. 총페놀 함량의 경우 저장 초기에 비하여 저장 28일 후 A 녹차 음료는 71.50%, B 녹차 음료는 73.88%, C 녹차 음료는 75.07%로 감소하였다. DPPH 라디컬 소거능은 저장 초기에 비하여 A 녹차 음료는 87.87%, B 녹차 음료는 92.93%, C 녹차 음료는 88.39%이었다. 녹차의 유용 카테킨인 epigallocatechin gallate (EGCG)는 28일간 저장 후에 A 녹차 음료는 130.61%, B 녹차 음료는 136.47%, C 녹차 음료는 4.34%이었다. 이상의 결과는 녹차의 저장 조건이 녹차 음료의 성분에 영향을 미치며, 빛, 질소 치환, 비타민 C가 매우 중요함을 시사하였다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권10호
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• pp.483-491
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• 2005

To solve the 3D eddy current problems by using FE(finite element) method with MVP(magnetic vector potential) and electric scalar potential, Coulomb gauge condition and current continuity condition have to be considered. Coulomb gauge condition enforced on existing FE formulations to insure the uniqueness of MVP looks unnatural and current continuity condition which can be driven from Ampere's law looks unnecessary. So in this paper the effect of two conditions on FE formulations are investigated in order to help to obtain accurate numerical simulation results.

• 대한기계학회논문집B
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• 제33권3호
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• pp.164-169
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• 2009

The slip velocity and the temperature jumps for low-speed flow in microchannels are investigated using Langmuir slip boundary condition. This slip boundary condition is suggested to simulate micro flow. The current study analyzes Langmuir slip boundary condition theoretically and it analyzed numerically micro-Couette flow, micro-Poiseuille flow and grooved microchannel flow. First, to prove validity for Langmuir slip condition, an analytical solution for micro-Couette flow is derived from Navier-Stokes equations with Langmuir slip conditions and is compared with DSMC and an analytical solution with Maxwell slip boundary condition. Second, the numerical analysis is performed for micro-Poiseuille flow and grooved microchannel flow. The slip velocity and temperature distribution are compared with results of DSMC or Maxwell slip condition and those are shown in good agreement.

• 한국미생물·생명공학회지
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• 제18권1호
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• pp.71-75
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• 1990

B.longum TK-100 및 L.acidophilus TK-2070으로 혼합배양한 culture로 제조한 요쿠르트는 냉장상태에서도 산생성이 되었느데 이는 B.longum TK-100에 의한 것보다는 대수기의 L.acidophilus TK-2070에 의하여 거의 생성되었다. B.longum TK-100은 편성 혐기조건 뿐만아니라 통성혐기조건에서도 생육이 좋은 것으로 나타냈다. 또한, B.longum과 L.acidophilus는 냉장보존 중인 요쿠르트 내에서도 생존도가 양호하므로 발효유의 제조, 개발에 혼합 starter로서의 이용이 가능하다고 하겠다. 한편 aniline bule 0.1가 함유된 RCAM plate상에 나타난 B.longum TK-100의 colony는 직경이 약 2mm의 광택있는 회배색의 중심에 청색을 나타내었고, L.acidophilus TK-2070의 coiny는 직경이 약 1mm 의 회배색을 나타내어 쉽게 분별할 수 있다.

• 한국의학물리학회지:의학물리
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• 제30권1호
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• pp.22-31
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• 2019

Purpose: To develop a new diffusion-based functional MRI (fMRI) sequence to generate apparent diffusion coefficient (ADC) maps in single excitation and evaluate the contribution of b0 signal on neuronal changes. Materials and Methods: A diffusion-based fMRI sequence was designed with single measurement that can acquire images of three directions at a time, obtaining $b=0s/mm^2$ during the first baseline condition (b0_b), followed by 107 diffusion-weighted imaging (DWI) with $b=600s/mm^2$ during the baseline and visual stimulation conditions, and another $b=0s/mm^2$ during the last activation condition (b0_a). ADC was mapped in three different ways: 1) using b0_b (ADC_b) for all time points, 2) using b0_a (ADC_a) for all time points, and 3) using b0_b and b0_a (ADC_ba) for baseline and stimulation scans, respectively. The fMRI studies were conducted on the brains of 16 young healthy volunteers using visual stimulations in a 3T MRI system. In addition, the blood oxygen level dependent (BOLD) fMRI was also acquired to compare it with diffusion-based fMRI. A sample t-test was used to investigate the voxel-wise average between the subjects. Results: The BOLD data consisted of only activated voxels. However, ADC_ba data was observed in both deactivated and activated voxels. There were no statistically significant activated or deactivated voxels for DWI, ADC_b, and ADC_a. Conclusions: With the new sequence, neuronal activations can be mapped with visual stimulation as compared to the baseline condition in several areas in the brain. We showed that ADC should be mapped using both DWI and b0 images acquired with the same conditions.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제9권1호
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• pp.47-53
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• 1998

이 연구에서는 세 가지 치료조건을 조성하여 각 치료조건간의 반향어 발생률과 치료효과를 비교하였다. 치료조건1(A)은 치료사가 아동에게 쉽고 짧은 질문을 하는 ‘대화조건’ 이고, 치료조건2(B)는 아동이 치료사가 하라는 지시에 따라 쉬운 과제를 수행하는 ‘과제수행조건’ 이고, 치료조건3(C)은 보상과 통제를 사용하는 ‘강화의 조건’ 이다. 연구설계는 A-B-A-B-BC-B-BC를 사용하였다. 이 연구는 발달연령이 3~4세 수준인 2명의 남아(11세, 12세)에게 실시되었는데, 반향어 치료는 1회기에 15분씩, 하루에 5~6회를 2주간 실시하였다. 반향어 치료를 위한 개입은 즉각 반향어에만 적용했고, 지연 반향어는 치료 개입없이 관찰만 하였다. 아동1의 즉각 반향어 치료결과(평균 비율)는 A(99%)-B(65%)-A(95%)-B(10%)-BC(7%)-B(6%)-BC(7%)로 나왔고, 아동2의 치료결과는 A(67%)-B(62%)-A(63%)-B(35%)-BC(8%)-B(4%)-BC(0%)로 나왔다. 아동1의 지연 반향어는 치료 개입 전후를 통해 3% 수준으로 큰 차이없이 낮은수준을 유지했고, 아동2의 지연 반향어는 강화의 조건 병행 전에는 $35{\sim}57%$ 수준이던 것이 강화의 조건 개입 후에는 $5{\sim}9%$ 수준으로 감소하였다. 이 연구의 결론은 대화상황에서 아동의 반향어를 교정하기보다는 아동에게 쉬운 과제를 수행하는 학습환경을 조성해주는 것이 반향어를 감소시키는데 도움이 되고, 과제수행 학습환경에서 과제수행 행동을 보상하고, 반향어 행동을 통제하는 방법을 사용하면, 반향어 감소는 물론 반향어 치료효과가 아동의 전반적인 언어발달에도 긍정적인 영향을 줄 수 있음을 말해주고 있다.

• Journal of applied mathematics & informatics
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• 제22권1_2호
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• pp.95-112
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• 2006

In this paper, the authors investigate the condition number with their condition numbers for weighted Moore-Penrose inverse and weighted least squares solution of min /Ax - b/M, where A is a rank-deficient complex matrix in $C^{m{\times}n} $ and b a vector of length m in $C^m$, x a vector of length n in $C^n$. For the normwise condition number, the sensitivity of the relative condition number itself is studied, the componentwise perturbation is also investigated.

• 제어로봇시스템학회논문지
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• 제11권11호
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• pp.895-900
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• 2005

We derive a linear matrix inequality(LMI) condition guaranteeing that any invariant zeros of a triple (A, B, C) lie in the open left half plane of the complex plane, i.e. $C(sI-A)^{-1}B$ is minimum phase. The LMI condition is equivalent to a certain constrained Lyapunov matrix equation which can be found in many results relating to stability analysis or control design. We show that the LMI condition can be used to simplify various control engineering problems such as a dynamic output feedback control problem, a variable structure static output feedback control problem, and a nonlinear system observer design problem. Finally, we give some numerical examples.