• Proceedings of the Korean Fiber Society Conference
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• 1991.06b
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• pp.88-88
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• 1991

• Feed Journal
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• v.2 no.6
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• pp.98-101
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• 2004

이 시기에는 돼지의 골격이 발달하는 시기이므로 고단백, 고에너지 사료인 젖먹이 및 육성돈 사료를 무제한 급여할 것이며, 육성초기인 포유기에는 고형사료에 대한 소화흡수 능력이 부족하므로 이에 알맞는 효성활성제가 포함된 고농축 사료를 급여해야한다. (중략)

• Proceedings of the Korea Multimedia Society Conference
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• 2003.05b
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• pp.733-736
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• 2003

최근 소프트웨어 프로세스 개선을 통하여 개발되는 소프트웨어의 품질을 향상시키기 위하여 개발 조직의 ?f발 능력과 생산성을 향상시키기 위하여 많은 회사들이 관심을 보이고 있다. 본 논문에서는 다양한 프로세스 심사 모델의 장점을 흡수하면서 조직 유형 및 프로젝트 규모에 제약 없이 프로세스 심사를 위한 개념을 제공하는 ISO/IEC 15504(SPICE)를 설명하고 최근의 심사사례를 바탕으로 전반적인 심사과정을 소개한다.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.1
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• pp.36-42
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• 2003

To identify the rapacity of waste leachate absorption in Populus euramericana and Betula platyphylla var, japonica, four different treatments were applied to seedlings: leachate solution (100% leachate), 50% dilution (50% leachate: 50% water, v/v) and 25% dilution, (25% leachate: 75% water, v/v) were applied to these two species. After the experiment, concentrations of heavy metals in tree parts were analyzed by an Inductively Coupled Plasma emission spectrometer (ICP). treatment with waste leachate significantly stimulated both Populus euramericana and Betula platyphylla var. japonica biomass production relative to the water control. In addition, these species showed good absorption capacity of As, Co, Hg and Ni elements. The results of this study suggested that these two species can absorb the toxic materials through their roots and transport them to stems or leaves.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.1
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• pp.86-91
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• 2008

The structural members must be designed to control characteristics of energy absorption for protecting passengers in a car accident. Study on collapse characteristics of structural member is currently conducted in parallel with other studies on effective energy absorption capacity of structural members with diverse cross-sectional shapes and various materials. This study concerns the crashworthiness of the widely used vehicle structural members, square thin-walled tubes, which are excellent in the point of the energy absorption capacity. The absorbed energy, mean collapse load and deformation mode were analyzed for side member which absorbs most of the collision energy. To predict and control the energy absorption, controller is designed in consideration of its influence on height, thickness and width ration in this study. The absorbed energy and mean collapse load of square tubes were increased by $15{\sim}20%$ in using the controller, and energy absorbing capability of the specimen was slightly changed by change of the high controller's height.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.2
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• pp.92-102
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• 1992

Prediction of energy absorption for bow structure is important for a design of protective structures against collision. For the crushing behaviour of basic element of energy absorption, the plastic mechanism method is applied. The ship's crushing strength of bow section is obtained by summing the energy dissipated in all individual elements. The theoretical predictions are compared with experimental results for ship's bow models published with experimental results for ship's bow models published in the references, and it is observed that the present prediction method of crushing strength correlates well with the experimental results.

• Journal of the Korean Solar Energy Society
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• v.31 no.2
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• pp.8-15
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• 2011

제습기의 역할은 태양열제습냉방시스템 요소 중에서도 매우 중요하다. 본 논문은 이러한 특성에 맞추어 제작된 장치를 갖고서 제습능력에 영향을 미치는 유량비를 바꾸어 실험한 결과이다. 실험은 크기가 $40m^3$인 항온항습실을 대상으로 이루어졌으며, 향류형 제습기의 수직 높이는 0.4m로 고정되었다. 또한 충진층은 액체흡수제와의 접촉면을 넓게하기 위하여 플라스틱 충진재로 채워져 있으며, 흡수제의 온도는 빠른 변화를 보기 위하여 $15^{\circ}C$로, 농도는 40%로 고정하였다. 액체흡수제의 유량과 습도가 높은 공기의 유량을 각각 3단계로 바꾸어 실험한 결과, 풍량이 높을수록 제습기 효과는 낮아졌으나, 전체적인 제습량에서는 많아졌다. 한편, 제습기에서 액체흡수제 유량이 많을수록 제습되는 수분량이 많아졌으나, 시간의 변화에 따라 제습되는 속도는 현저하게 낮아졌다. 따라서, 향후 실험에서는 유량의 변화 폭을 더욱 확대해서 많은 실험 결과를 확보하고, 이를 모델링화 하여 높은 정확도를 예측할 필요가 있다.

• Composites Research
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• v.20 no.3
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• pp.8-16
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• 2007

Bending collapse of light-weight square tubes used for vehicle structure components is a dominant failure mode in oblique collision and rollover of vehicles. In this paper bending performances of aluminum-GFRP hybrid tube beams were evaluated in relation with bending deformation behavior and energy absorption characteristics. Aluminum/GFRP hybrid tube beams fabricated by inserting adhesive film between prepreg and metal layer were used in the bending test. Failure mechanisms of hybrid tubes under a bending load were experimentally investigated to analyze the bending performance as a function of ply orientation and composite layer thickness. Ultimate bending moments and energy absorption capacity of hybrid tube beams were obtained from the measured load-displacement corves. It was found that aluminum/GFRP hybrid tubes could be converted to rather stable collapse mode showing excellent energy absorption capacity in comparison to the pure aluminum tube beams. In particular, the hybrid tube beam with $[0^{\circ}/90^{\circ}]s$ composite layer showed a large improvement by about 78% in energy absorption capacity and by 29% in specific energy absorption.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.116-122
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• 2021

This study quantitatively evaluated the performance improvement of a circular reinforced concrete pier under dynamic load with strengthening using a steel plate. Various three-dimensional elements were applied using the finite element program ABAQUS. The analytical parameters included the ratios of the steel cover length to the pier's total height and the ratios of the steel cover thickness to the pier diameter for inelastic-nonlinear analysis. The lower part of the pier had fixed boundary conditions, and lateral repetitive loads were applied at the top of the pier. The pier was investigated to evaluate the dynamic performance based on the load-displacement curve, stress-strain curve, ductility, energy absorption capability, and energy ratio. The yield and ultimate loads of piers with steel covers increased by 3.76 times, and the energy absorption capability increased by 4 times due to the confinement effects caused by the steel plate. A plastic hinge part of the column with a steel plate improved the ductility, and the thicker the steel plate was, the greater the energy absorption capacity. This study shows that the reinforced pier should be improved in terms of the seismic performance.

• Journal of Periodontal and Implant Science
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• v.24 no.1
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• pp.155-164
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• 1994

치조골흡수는 만성치주질환의 전형적인 증상이다. 골흡수에 작용하는 여러 요인들 중에서도, 특히 최근에 들어서 몇몇 cytokine들에 대한 관심이 높아지고 있는데, interleukin-1(IL-1), tumor necrosis factor(TNF) 및 interleukin-6(IL-6) 등이 치주질환의 진행과정에서 중요한 치조골흡수요인으로 제안되고 있다. 본 연구의 목적은 신생쥐의 골조직 배양실험을 통해서 recombinant human $interleukin-1{\beta}$ ($rHuIL-1{\beta}$), recombinant human tumor necrosis $factor-{\alpha}$($rHuTNF-{\alpha}$) 및 recombinant human interleukin-6(rHuIL-6) 의 골흡수 유도효과를 알아보고, cyclooxygenase 억제제인 indomethacin과 recombinant murine $interferon-{\gamma}$($rMurIFN-{\gamma}$)가 이들 cytokine의 골흡수 유도능력에 미치는 영향을 알아봄으로써 이들 cytokine의 작용기구에 대해서 알아보고자 하는데 있다. 생후 1-2일된 쥐에게 $1{\mu}Ci^{45}CaCl_2$를 피하주사하고 4일 후에 쥐를 희생시켜 $^{45}Ca$ 로 표지된 두개골을 얻어 24시간 전배양 후, 각 cytokine ($rHuIL-1{\beta}$, $rHuTNF-{\alpha}$ 및 rHuIL-6)과 cytokine 및 첨가약제 (indomethacin 및 $rMurIFN-{\gamma}$)가 함유된 배지로 교환하여 48시간 배양한다. 골흡수 유도효과는 두개골에서 48시간의 배양 중 유리되는 $^{45}Ca$의 방사능 정도로 평가하였다. 본 연구를 통해 다음과 같은 결과를 얻었다. 1. $rHuIL-1{\beta}$ ($10^{-12}-10^{-9}M$) 및 $rHuTNF-{\alpha}$ ($10^{-10}-10^{-8}M$)는 농도변화에 따르는 골흡수 유도효과를 보였으나 , rHuIL-6 ($10^{-10}-10^{-8}M$)는 유의할 만한 효과를 보이지 않았다. 2. Indomethacin ($10^{-6}M$)은 $rHuIL-1{\beta}$ 및 $rHuTNF-{\alpha}$의 골흡수 유도작용에 유의할 만한 억제효과를 나타내지 않았다. 3. $rMurIFN-{\gamma}$ (1000 U/ml) 은 $rHuIL-1{\beta}$ 및 $rHuTNF-{\alpha}$의 골흡수 유도작용에 유의한 억제효과를 나타내었다. 본연구를 통해 치주질환 환자의 치주조직에서 검출되는 $IL-1{\beta}$ 및 $TNF-{\alpha}$가 치조골 흡수에 중요한 역할을 할 것으로 생각된다.