• 통상정보연구
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• 제4권2호
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• pp.97-119
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• 2002

This research purposes on comparing some e-trailing models in character and presenting the obstacles of e-trailing activation and the solutions, e-trailing models this research has studied are 1) Bolero, 2) TradeCard, 3) BeXcom, 4) Identrus, and 5) TEDI etc. Comparing characteristic points of the e-trading models are as follows ; 1) Access ways as a global e-trading model, 2) Structural characteristic, 3) Functional characteristic, 4) Role as a global e-trading model, 5) Legal issues, 6) Application issues in practice, 7) Security issues for Technology.

• Elastomers and Composites
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• 제53권1호
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• pp.1-5
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• 2018

In the current research, the curing kinetics of a mixture system consisting of a Bisphenol-A type vinyl ester resin and styrene monomer was studied. Methylethylketone peroxide and cobalt octoate were used as the polymerization initiator and accelerator respectively. Thermograms with several different heating rates were obtained using non-isothermal differential scanning calorimetry. Activation energy values analyzed by the Flynn-Wall-Ozawa isoconversional method showed a three-step change with conversion ${\alpha}$: a slight decrease initially for ${\alpha}$ < 0.1, a constant value of 47.9 kJ/mol in the range 0.1 < ${\alpha}$ < 0.7, and a slow increase for 0.7 < ${\alpha}$. When assuming a constant activation energy of 47.9 kJ/mol, an autocatalytic model of the Sestak-Berggren equation was considered as the proper mathematical model of the conversion function, indicating an overall order of 1.2.

• Food Science and Biotechnology
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• 제16권6호
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• pp.954-957
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• 2007

Gelation mechanism of xanthan-carob mixture (X/C) was investigated based on thermorheological behavior. Three X/C ratios (1:3, 1:1, and 3:1) were studied. Small amplitude oscillatory shear tests were performed to measure linear viscoelastic behavior during gelation. Temperature sweep ($-1^{\circ}C/min$) experiments were conducted. Using a non-isothermal kinetic model, activation energy (Ea) during gelation was calculated. At 1% total concentration, the Ea for xanthan fraction (${\phi}_x$)=0.25, 0.5, and 0.75 were 178, 159, and 123 kJ/mol, respectively. However, a discontinuity was observed in the activation energy plots. Based on this, two gelation mechanisms were presumed-association of xanthan and carob molecules and aggregation of polymer strands. The association process is the primary mechanism to form 3-D networks in the initial stage of gelation and the aggregation of polymer strands played a major role in the later stage.

• 대한전기학회논문지:시스템및제어부문D
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• 제52권9호
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• pp.560-567
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• 2003

EMG recordings of the electrical activity of muscle have proved to be a valuable tool in studying muscle function and reflex activity. SP(silent period) is elicited by a electrical stimulation on the chin during isometric contraction of jaw muscle. This paper proposes a model of the inhibitory reflex mechanism of jaw muscle after electrical stimulation. The SPs of jaw muscle after a electrical stimulation to the chin were divided into SP1 and SP2. SP1 is produced by the activation of periodontal receptors. The activation of nociceptors contributes to the SP2. As a result, the EMG signal generated by a proposed a model of inhibitory reflex mechanism is similar to real both EMG signal including SP1 and SP2. The present study have shown differences of SP1 and SP2 induced by inhibitory reflex mechanism.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 가을 학술논문 발표대회
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• pp.121-122
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• 2022

In this study, compared and analyzed various Activation Functions to present a methodology for developing a natural intelligence-based prediction system. As a result of the analysis, ELU was the best with RMSE: 62.87, R²: 0.96, and the error rate was 4%. However, it is considered desirable to construct a prediction system by combining each algorithm model for optimization.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2022년도 추계학술대회
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• pp.383-384
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• 2022

Gas Combustion Unit (GCU) onboard liquefied natural gas carriers handles boil-off to stabilize tank pressure. There are many factors for LNG cargo operators to take into consideration to determine whether to use GCU or not. Gas consumption of main engine and re-liquefied gas through the Partial Re-Liquefaction System (PRS) are good examples of these factors. Human gas operators have decided the operation so far. In this paper, some deep learning neural network models were developed to provide human gas operators with a decision support system. The models consider various factors specially into GCU operation. A deep learning model with Sigmoid activation functions in input layer and hidden layers made the best performance among eight different deep learning models.

• IMMUNE NETWORK
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• 제20권3호
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• pp.22.1-22.21
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• 2020

In the progression of atherosclerosis, macrophages are the key immune cells for foam cell formation. During hyperlipidemic condition, phagocytic cells such as monocytes and macrophages uptake oxidized low-density lipoproteins (oxLDLs) accumulated in subintimal space, and lipid droplets are accumulated in their cytosols. In this review, we discussed the characteristics and phenotypic changes of macrophages in atherosclerosis and the effect of cytosolic lipid accumulation on macrophage phenotype. Due to macrophage plasticity, the inflammatory phenotypes triggered by oxLDL can be re-programmed by cytosolic lipid accumulation, showing downregulation of NF-κB activation followed by activation of anti-inflammatory genes, leading to tissue repair and homeostasis. We also discuss about various in vivo and in vitro models for atherosclerosis research and next generation sequencing technologies for foam cell gene expression profiling. Analysis of the phenotypic changes of macrophages during the progression of atherosclerosis with adequate approach may lead to exact understandings of the cellular mechanisms and hint therapeutic targets for the treatment of atherosclerosis.

• Korean Chemical Engineering Research
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• 제50권6호
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• pp.1086-1092
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• 2012

본 촉매가스화 실험에서 촉매로서 가치가 있는 천연광물과 순수촉매를 사용하여 저급석탄의 $CO_2$분위기하 활성화 에너지 및 생성된 합성가스의 성분을 분석하였다. 먼저 공업 분석과 원소 분석을 통해 6가지 저급석탄의 회분과 황 함유량을 측정하였다. 그 후 Thermogravimetric Analyzer (TGA)를 통해 저급석탄 열분해반응 특성을 고려하여 실험에 가장 적합한 저급석탄을 선정하였다. 선정된 삼화 저급석탄은 촉매와 섞어 $CO_2$분위기하 TGA실험을 진행하였으며, 결과를 토대로 Kissinger 방법을 이용한 활성화 에너지를 구하였다. 또한 shrinking core model을 이용해 활성화 에너지를 구하여 Kissinger 방법과 비교하였다. 그리고 반응기에서 이산화탄소 분위기하 생성된 합성가스는 Gas Chromatography (GC)를 이용하여 분석하였다. 가스를 분석한 결과 수소의 생성량은 $K_2CO_3$를 촉매로 사용하였을 경우 가장 크게 나타났으며, 앞서 구한 활성화 에너지 결과와 일치하는 경향을 나타내었다.

• Journal of Acupuncture Research
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• 제23권6호
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• pp.103-115
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• 2006

Objectives : Rheumatoid arthritis(RA) is a systemic & a chronic inflammatory autoimmune disease . A chronic , locally destructive inflammmatory reaction in human is examplified by the synovitis present in some connective tissue disorder. The presence of a number of cytokines, $TNF-{\alpha}$, iNOS & expression of nitric oxide, NF-kB p65 activation implies an important role of cellular immune response in RA inflammatory reaction. This study was designed to evaluate on the effects of the Homnis Placenta herbal acupuncture on EX-LE201 & ST 35 reducing expression of LPS-induced arthritis model in mice. Materials and Methods : Homnis Placenta herbal acupuncture was inserted into 10 rats induced rheumatoid arthritis. The acupunctures were injected into the EX-LE201 and ST35 points. Such indexes were measured the inhibition of inducible nitric oxide synthase(iNOS) expression, nitric oxide(NO) production in vitro experiment and Tumor Necrosis $Factor-{\alpha}(TNF-{\alpha})$ & Nuclear Factor kappa $B(NF-{\kappa}B)$ p65 activation, synovial hyperplasia, angiogenesis and fibrosis in synovial membrane of knee joint of mice in vivo experiment. Results : 1.Homnis Placenta Herbal acupuncture inhibited iNOS mRNA and NO in RAW 264.7 cell of LPS-induced rheumatoid arthritis in a dose dependent manner. 2.Homnis Placenta Herbal acupuncture also showed significant inhibition of $TNF-{\alpha}$ & $NF-{\kappa}B$ p65, activation, synovial hyperplasia, angiogenesis and fibrosis in synovial membrane of knee joint of mice. Conclusion : These results suggest that Homnis Placenta Herbal acupuncture has an therapeutic effects on LPS induced-rheumatoid arthritis by inhibiting $TNF-{\alpha}$ activation.

• 한국화재소방학회논문지
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• 제34권4호
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• pp.45-51
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• 2020

본 연구에서는 스프링클러 헤드의 해석모델을 통해 화재성장모드별 스프링클러 작동시 연층기류의 열유동조건을 파악하고자 한다. 화원은 최대발열량 3 MW의 시간제곱의 화재성장을 가정하였다. 시험대상 스프링클러헤드는 작동온도 65~105 ℃, RTI 25~171 m^1/2s^1/2 범위의 표준형과 조기반응형 8종을 대상으로 한다. 연층기류의 온도와 감열부의 온도차는 화재성장이 느리고 스프링클러 헤드의 RTI값이 작을수록 감소하는 경향을 보였다. 스프링클러 헤드 작동 순간의 연층 기류 온도와 속도조건은 전체적으로 시험기준의 범위와 비교적 잘 일치하고 있으나 저성장 화재에서는 최저시험기준 이하의 온도와 속도조건에서 작동이 이루어질 수 있음을 파악하였다. 본 연구는 스프링클러 헤드의 작동에 대한 기초연구로서 시험기준의 신뢰성을 향상시키는데 기여할 수 있다.