• Journal of the Korean Magnetics Society
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• v.2 no.2
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• pp.105-113
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• 1992

조성이 Mn$_{x}$Zn$_{1-x}$ Fe$_{2}$O$_{4}$ 훼라이트(x=0.75, 0.52)를 pusher type 연속 전기로를 이용하여 질소 분위기하에서 1360 .deg. C 로 3시간 동안 소결하여 얻어냈다. 본 연구에서는 스피넬 구조인 Mn-Zn 훼라이트의 FMR(Ferrimagnetic Resonance) 스펙트럼 특징과 초기투자율과의 상관성을 조사하고자 EPR X-band 스펙 트로미터를 이용 9.50 GHz의 microwave frequency에서 FMR 실험을 수행하였다. FMR 공명흡수선은 주 자기공명 흡 수선외에 낮은 자기장에서 약한 subsidiary 공명흡수선을 나타내는데 온도변화에 따른 주 자기공명 흡수선과 sub- sidiary 공명흡수선(제2, 제3 공명흡수선)의 세기, 공명선폭, g값 등의 온도 의존성을 연구함으로써 제2 공명흡수 선이 나타나는 원인을 분석하였으며, 자기공명 흡수선의 g값, 자기공명선 세기, 그리고 공명선폭과 초기투자율의 상관성을 연구하였다. 실험 결과 주 자기공명 흡수선의 g값, 자기공명선 세기, 공명선폭은 초기투자율 값과 밀접 한 관련이 있음을 확인할 수 있었다.었다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.412-414
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• 2003

그리드 자원 관리는 지리적 분산과 이 기종 컴퓨팅 자원의 활용 그리고 인터넷 웹 환경에 주안점을 두고 설계되어야 한다. 이를 위해서 기존 부분기능 위주의 모델을 포괄하면서도 전체적인 상호협력 동작에 기반한 3개 기본요소와 8기관의 그리드 자원 관리 모델을 제시한다. 이를 통해 전체적인 관점에서 그리드 자원관리를 평가할 수 있는 G값을 살펴보고, G값을 기준으로 하여 최적의 그리드 자원관리 방안을 모델링 한다.

• Journal of the Korean Chemical Society
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• v.27 no.4
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• pp.244-254
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• 1983

Single crystals of sodium thiosulfate $(Na_2S_2O_3) have been grown from the saturated solution by the evaporation method at the optimum condition. Radiation damages in the crystal by ${\gamma}$-irradiation of $20{\times}10^6$ Rontgen have given rise to paramagnetic centers. The anisotropic spectra of each paramagnetic species have been obtained with the X-band EPR spectrometer at room temperature. When an isotropic D.P.P.H. at g value of 2.0036 is based on. ESR Spectra of the single crystal are recorded for each rotation about the perpendicular a, b and c axis with intervals of $10^{\circ}$ from $0^{\circ}$to $180^{\circ}$ in order to find out the properties of the crystal for anglar variation of the anisotropic peaks. The g values are calculated from the line position between the anisotropic peaks and the isotropic peaks of D.P.P.H. and then principal g values and their direction cosines of the species is obtained by the diagonalization of 9 matrix elements of the corresponding g values. From the analysis of the characteristic principal g values and direction cosines for ${\gamma}$-irradiated $Na_2S_2O_3$ crystal, anisotropic peaks corresponding to $SO_2^+, SO_2^- $are identified and the existences of unidentified and unstable paramagnetic defects are verified.

• Clean Technology
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• v.18 no.4
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• pp.404-409
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• 2012

In this study, the effects of mixing intensity and coagulant dosages on the characteristics of floc growth for phosphorus removal were investigated. The experiments were conducted under Al/P molar ratio of 1.0, 1.5 and 2.0; rapid mixing intensity with G value of 100, 300, and 500 $s^{-1}$. The characteristics of floc growth were measured by flocculation index (FSI) and the removal efficiencies of phosphorus by using different size filters. The removal efficiencies of soluble phosphorus increased as Al/P molar ratio and rapid mixing intensity increased. However, the highest removal efficiencies of T-P were observed at G value of 300 $s^{-1}$. When Al/P molar ratio was lower than 1.0, the value of FSI at G value of 500 $s^{-1}$ was the largest. However, when Al/P ratio was larger than 1.0, the value of FSI at G value 300 $s^{-1}$ was the largest. Effects of mixing intensity and Al/P molar ratio on coagulation for phosphorus removal of synthetic and real wastewater effluent were observed to be similar.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.7438-7442
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• 2014

An assessment of flocculation was performed by measuring the distribution of the floc size during sedimentation in water works. The size and number of flocs have a greater effect on an evaluation of the efficiency of flocculation rather than the turbidity. The data was collected in situ using particle image velocimetry and image analysis. The measurements were carried out at a water depth of 1m. The removal efficiency of the total organic compounds, UV absorbance and turbidity depended on the size and floc size distribution in flocculation as the G value. The G value of 50 sec-1, 30 sec-1 and 10 sec-1 showed the highest degree of efficiency in the case of an inlet water turbidity of 5 NTU, and the highest degree of efficiency was observed at a G value of 65 sec-1, 40 sec-1 and 10 sec-1 when the inlet water turbidity was 263 NTU. The number of flocs with a distribution of above $1,200{\mu}m$ was 14. The dynamics between two important growth mechanisms were investigated as the energy input changed. This is a certain method that makes use of the size and number of flocs as an efficiency assessment.

• Composites Research
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• v.16 no.5
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• pp.45-53
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• 2003

The experimental and numerical investigations on the failure characteristics of the secondary bonded composite single-lap joints were performed. The initiations and growths of cracks were observed using CCD camera and acoustic emission sensor during the tension tests of the joint specimens. The structural behaviors of the specimens were predicted by the geometric nonlinear two-dimensional finite element analysis. The three types of observed initial cracks were included in each finite element models and the strain energy release rates of each specimen models were calculated by VCCT(Virtual Crack Closure Technique) technique. The tension tests showed that the initial cracks occurred in the 60∼90% of final failure loads and the major failure modes of the specimens were adhesive failure and the delamination between the 1st and 2nd ply of laminate. The specimens with the thicker bondline had earlier crack initiation loads but higher crack propagation resistance and eventually better loading capability. The delaminations were mostly observed in the thicker bondline specimens. The mode I values of calculated strain energy release rates were higher than the mode II values in the all specimen models considering the three types of initial cracks. The mode I and total strain energy release rates were calculated as higher values in the order of initial crack in the edge interface, comer interface and delamination between the plies of laminate.

• The Korean Journal of Food And Nutrition
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• v.14 no.6
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• pp.585-590
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• 2001

The purpose of this study was to examine physical properties of the addition of Plantago powder on bread flour and dough fheology of white pan bread. Four levels(0.3, 0.6, 0.9 and 1.2%) of each Plantago powder with bread flour were tested for their effects in dough mixing using rapid visco analyzer, alveogram, farinogram and sensory test. Addition of Plantago powder(0.3, 0.6 and 0.9% ) showed almost same tendency on the initial pasting temperature but 1.2% increased it. Increment of Plantago powder showed increment of peak viscosity and final viscosity, L(extensibility) and G(swelling index) value in alveogram showed decrement with increasing Plantago powder. In farinogram the use of Plantago powder increased consistency and water absorption but decreased development time and stability. White pan bread using Plantago powder had higher value of Max. G and gardeness in rheometer than without using it. Sensory evaluation of white pan bread with 0.6% Plantago powder had the highest score.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.1
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• pp.23-26
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• 1980

This study was attempted to establish the basic data for evaluating the processing suitability of the mussel, Mytilus edulis, cultured by hanging method in Yeosu Bay, Korea. Seasonal variations in condition index and chemical .composition of the mussel were carried out from March 1978 to February 1979. The results are as follows: 1. The condition index was highest from December to April next year. 2. The glycogen content of mussel was 2.7 to $3.9\%$ from December to May next year and revealed the maximum value, $3.9\%$ in December and March. F and G-values as the condition indices of the mussel showed also the highest value from December to March. 3. The protein content of mussel was highest from July to August. 4. By the results of condition index and chemical composition of the mussel, the suitable harvest season as raw materials for processing is determined to be from December to April next year and from July to August.

• Journal of Korean Society of Water and Wastewater
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• v.9 no.4
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• pp.63-72
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• 1995

The mean velocity gradient, G, has been used as a principal design and operation parameter for flocculation unit. This paper questions that significance. The physical and qualitative meaning of collision efficiency factors of each transport mechanism (Brownian motion, fluid shear, and differential sedimentation) are reviewed. The overall collision frequency function is calculated by summing up the collision frequency function of each mechanism. In the collision of two particles of different size, a diagram showing the dominant region in which each mechanism is important is developed and the meaning of the diagram is discussed. The primary ramification of this curvilinear, heterodisperse approach is that G is found to be not nearly so important. Previous experimental work in which the role of G has been examined is reviewed in light of this finding.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.273-274
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• 2006

칼라기반 영상 검색에서 칼라의 색상 정보를 이용하는 기법에 많은 연구가 진행되고 있다. 본 논문에서는 칼라의 색상 정보와 명암 정보인 Gray-level의 특징자를 이용해서 영상을 검색하는 시스템을 제안한다. 칼라영상의 RGB 각각의 픽셀 값들을 R값, G값, B값의 크기순으로 배열하고 칼라 그레이-레벨을 구한 뒤 양자화 한다. 이러한 칼라의 특징 정보를 사용함으로써 이미지의 확대, 축소, 회전에도 강인한 검색을 할 수 있음을 실험을 통하여 성능의 우수함을 보였다.