• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.152-153
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• 2009

• Korean Journal of Environment and Ecology
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• v.31 no.5
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• pp.433-443
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• 2017

Securing the species compositional integrity (typicalness and representativeness) is the essential prerequisite for an integrated management of vegetation resources using the phytosociological $relev\acute{e}s$ and plant communities of the Z.-M. school. This study is intended to develop a tool for qualitative and quantitative evaluation of species compositional homotoneity of a set of $relev\acute{e}s$ per syntaxon. The new homotoneities, actual homotoneity ($H_{act}$), and optimal homotoneity ($H_{opt}$) taking into account the heterogeneous factors of $relev\acute{e}s$ are proposed. The correlations between the floristic variables such as the vegetation type, the new homotoneities, and the previously studied homogeneous measures (e.g. Pfeiffer's homogeneity, basic homotoneity-coefficient, corrected homotoneity-coefficient, and mean floristic similarity) are analyzed by using Spearman's rank correlation coefficient. $H_{act}$ and $H_{opt}$ are effective in determining the difference of inter-synthesized units and of inter-$relev\acute{e}s$, respectively. $H_{act}$ is the homotoneity that is the most independent of the number of $relev\acute{e}s$. On actual vegetation with long-term human impact in the Korean Peninsula, $H_{opt}$ has become an aid to the more precise understanding of $H_{act}$ as substantive homogeneousness of species composition of syntaxa. It is expected that $H_{act}$ and $H_{opt}$ can be used for the selection of a sort of homogeneous vegetation data to build a phytosociological $relev\acute{e}$-database with consistency and objectiveness for national vegetation resources.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2009.04a
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• pp.47-50
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• 2009

본 논문에서는 불균질 재료의 균열진전을 해석하기 위한 방법으로 변절점 유한요소를 이용한 멀티스케일 기법을 제시하였다. 효율적인 해석을 위하여 서로 다른 스케일의 요소망을 적용하여 전체 모델의 자유도를 감소시킨다. 균열선단과 비교적 멀리 떨어져 있는 영역은 균질화 기법을 도입하여 불균질 재료에 대한 등가물성을 갖는 성긴 요소망으로 대체하고, 균열선단 주변의 요소망은 재료의 기하학적 특성과 불균질성을 반영하도록 조밀하게 구성한다. 한편 균열선단에 존재하는 응력 특이성을 표현하기 위하여 균열선단을 포함한 요소를 더욱 조밀한 요소망으로 분할하여 구성한다. 여기에서 서로 다른 스케일의 요소망 경계에는 변절점 유한요소를 적용함으로써 경계에서의 절점 연결조건과 적합성을 만족시킬 수 있다. 제시한 멀티스케일 기법을 수치예제에 적용함으로써 정확성과 효율성을 검증하였으며, 특히 불균질 성분이 균열진전에 미치는 영향을 경계조건과 T-응력의 관점에서 분석하였다.

• Journal of Korean Society of Steel Construction
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• v.28 no.3
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• pp.173-183
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• 2016

Various material characteristics of HSA800 steel were examined and a quantitative criteria about the homogeneity of the strength was proposed. Whether HSA800 steel is satisfied the criteria for homogeneity of the strength or not was also examined. From the test results, the material characteristics of 1/4 point from the extreme fiber in the Z-direction satisfied the KS requirements. The excellent directional properties and impact resistance at low temperatures were also showed from the test results. HSA800 steel satisfied the criteria of homogeneity for the strength of the steel. However, it showed that some structures were banded together at 2/4 point from extreme fiber in the Z-direction from the microscopic tests and attention is needed to be paid in that point.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.5
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• pp.1352-1363
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• 2015

This study was carried out to investigate the characteristics of the dependent variables depending on the condition changes of independent variable of the operation and the material during the production of collets added with rice and dried shrimp by using single extruder to utilize as basic data for the manufacture of extrusion collets. A total of 7 independent variables were set up as a raw, 20, 40 and 60 mesh for the powder particle size of rice; 12, 14, 16 and 18% for the moisture content of rice; 2, 4, 6 and 8% for the addition amount of dried shrimp; 90, 95, 100 and $110^{\circ}C$ for the barrel temperature; 210, 280 and 340 rpm for the screw speed; 4, 6, 8 and 10 mm for the discharge port diameter; 30, 40, 50 and 60 kg/h for the input amount of the mixed material. The characteristics of the dependent variables including puffing ratio, moisture content, lightness, uniformity, productivity of collets was to be studied by changing the conditions of the independent variables. As a results of this study, 20 mesh of powder particle size of rice, 14% of moisture content of rice, 4% of addition amount of dried shrimp, $100^{\circ}C$ of barrel temperature, 280 rpm of screw speed, 6 mm of discharge port diameter and 50 kg/h of input amount of mixed material were found to be the most preferable over other independent variables for the production of extrusion collets. In conclusion, it is necessary to set the independent variable in order to produce the high quality collets added with the rice as the main raw material and dried shrimp as the sub-materials.

• Korean Journal of Cognitive Science
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• v.12 no.4
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• pp.41-47
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• 2001

Palmer and Rock (1994) proposed that a connected region of uniform visual properties (uniform connectedness) strongly tends to be organized as a single perceptual unit To test this hypothesis using briefly presented forms three experiments were executed. In Experiment 1 and 2 participants were asked to report the identity of a post-cued target. and there was no difference between connected and disconnected displays. In Experiment 3 participants were asked to report the predesignated name of each whole display and the accuracy rate was higher in the connected displays than in the disconnected ones. However negative repetition effects were observed consistently in all the experiments. This indicates uniform connectedness does not have a strong effect in perceiving briefly presented forms.

• Tunnel and Underground Space
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• v.13 no.2
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• pp.117-124
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• 2003

The fracture processes under static tensile loading were simulated using a proposed numerical simulation method, based on finite element method and fracture mechanism, and analyzed to verify an influence of rock inhomogeneity on static tensile strength. Static tensile strengths for the specimen models with different spatial microscopic tensile strength when m=5 and m=50 were estimated. These analyses revealed that the static tensile strength becomes closer to the mean microscopic tensile strength at a higher uniformity coefficient and the scatter of the strength data decreases in increasing the uniformity coefficients. Therefore, it could be concluded that rock inhomogeneity has an effect on static tensile strength.

• Journal of the korean Society of Automotive Engineers
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• v.14 no.6
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• pp.1-8
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• 1992

본 고에서는 균질화법의 정식화를 이용하여 복합재료의 거시적 균질화된 재료상수를 구하고, 이 재료상수를 이용하여 거시구조물의 변형과 응력을 구하고, 이로부터 다시 미시구조의 응력분포와 변형도를 구하는 방법을 기술하였다. 주기성을 가정한 균질화법은 복합재료 구조물의 물성평가와 거동예측에 대한 매우 적절한 수치해석 방법이다. 균질화법은 이러한 선형변형의 문제뿐만 아니라, 내압을 존재하는 빈공간 소재의 물성, 기지재료와 강화재료 계면의 미끄러짐 등으로 인한 미세 파손현상 등의 예측이 가능하다. 그외에도 탄소성 대변형 거동 이론과 균질화법을 함께 적용하여, squeeze casting에서 발생하기 쉬운 계면분리나 파단 등의 미소결함과 같은 2차 성형성의 예측도 가능하다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.176-179
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• 2001

비 수용성 유기오염물(NAPL; non-aqueous phase liquid)로 오염된 불균질 토양을 계면활 성제를 이용하여 정화할 경우 효율성을 알아보기 위해 칼럼 및 박스 실험을 실시하였다. 불 균질한 지하 내부구조는 정화효과에 커다란 영향을 끼치는 것으로 알려져 있으나 이에 대한 연구는 매우 미비한 형편이다. 2차원 불균질 분포를 잘 나타내주는 박스실험을 통하여 실제 지하매질에 가까운 조건에서 실험을 실시하였다. PCE(tetrachloroethylene)와 xylene이 NAPL로 올리에마이드(01eamide)가 비이온-계면활성제로 이용되었으며, 1%용액과 증류수를 주입하여 NAPL을 세정하였고 가스크로마토그래피를 이용하여 NAPL의 농도를 분석하였다. 계면활성제를 주입할 경우가 증류수를 주입할 때보다 최대유출농도가 약 200배 정도가 높게 나타났으며 빠른 시간 내에 대부분의 NAPL이 정화되었다. 본 실험을 통하여, 불균질 매질에서의 계면활성제를 이용한 토양세정방법의 효율성이 정량화 되었으며, 계면활성제를 이용한 채수주입법의 현장 적용가능성을 확인하였다.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.13 no.1
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• pp.1-27
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• 2002

The present study was designed to examine the effects of different homogenization pressure, homogenization temperature and $\beta$-cyclodextrin concentration on cholesterol decrease rate of Cheddar cheese, and to optimize the factors of cheese manufacture Process. Il. The hardness(control 5.46kg/$cm^2$), gumminess(control 5.24kg), chewiness(control 4.87kg/cm) reduced to 2.03kg/$cm^2$, 2.18kg, 2.24kg/cm, respectively. In the result of sensory analysis, treatment of homogenization for cholesterol removed Cheddar cheese improved appearance and flavor, however texture fell. In addition, the resent result of the study indicated that about 75.27% of cholesterol in Cheddar cheese could be removed, and the possibility of development of cholesterol decreased Cheddar cheese was observed.