• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 추계학술대회 논문집
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• pp.865-866
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• 2010

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.153-160
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• 2018

An environmentally favorable (chlorine-free) solid oxidizer, guanidinium dinitramide [GDN; $NH_2C(NH_2)NH_2N(NO_2)_2$], was newly synthesized from guanidine carbonate [$NH_2C(=NH)NH_2{\cdot}1/2H_2CO_3$]. Two different crystalline forms (${\alpha}-type$ and ${\beta}-type$) appeared according to the applied solvents and synthesis conditions. Moisture, during extraction, might become trapped in a crystal between inner molecules. Therefore, despite having the same chemical composition, Raman-IR and TGA-DSC revealed different physical characteristics of the two forms. Peaks of Raman shift near $1000cm^{-1}$ implied different chemical structures. Thermal analysis revealed an exothermic temperature $155.7^{\circ}C$ for ${\alpha}-type$ but one of $191.6^{\circ}C$ for ${\beta}-type$. The caloric value of ${\alpha}-type$ was 536.4 J/g, which was 2.5 times larger than that of the ${\beta}-type$, which was 1310 J/g. While the synthesized GDN of ${\alpha}-type$ showed a steep exothermic decomposition, the ${\beta}-type$ was slowly decomposed after melting through an endothermic process. This work implied that despite of the same molecular formula some different core thermal properties would appear depending on synthesis conditions.

• 자원리싸이클링
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• 제17권4호
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• pp.57-65
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• 2008

도시 소각재 용융슬래그로부터 반응시간 및 $SiO_2/Al_2O_3$의 비를 변화시키면서 Na-A형 제올라이트의 수열합성 거동에 대하여 고찰하였다. 반응시간에 대한 Na-A형 제올라이트를 수열합성한 반응물의 거동은 반응 초기에 첨가된 규산소다와 알루민산 소다가 먼저 반응하여 핵을 생성하였다. 생성된 핵은 시간이 지남에 따라 용융슬래그로부터 용해된 $SiO_2$ 및 $Al_2O_3$ 성분들과 반응하여 Na-A형 제올라이트로 성장되었다. 수열반응은 10시간 이내에 완결되며, 반응시간이 10시간 이상으로 증가하면 생성된 Na-A형 제올라이트가 용해되면서 하이드록시소달라이트로 변환되었다. 또한 $SiO_2/Al_2O_3=0.80{\sim}1.96$에서 Na-A형 제올라이트만 형성되었으나, $SiO_2/Al_2O_3=2.54$에서 Na-A형 제올라이트와 더불어 Na-P형 제올라이트가 생성되었다.

• The Korean Journal of Ceramics
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• 제4권1호
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• pp.5-8
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• 1998

Flat belt(FB) type high pressure apparatus has been succesfully utilized in various high pressure experimental stations in Korea and Japan to conduct HPHT (high pressure and high temperature) diamond synthesis. Present paper discusses pressure calibration of FB apparatus at high temperature to establish P-T condition of diamond synthesis. We also present some examples of controling P-T condition through careful experimental set-up of the high pressure sample cells. Finally we discuss reproducibility of pressure and temperature condition of the HPHT diamond synthesis.

• 대한기계학회논문집
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• 제17권6호
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• pp.1330-1341
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• 1993

본 연구에서는 회전대우(revolute joint)들로 이루어진 1자유도 평면기구들의 특성을 파악하고 그래이프이론(graph theory)을 이용하여 기구의 형태를 행렬로 표시 하여 체이터베이스에 저장하였다. 또한 기구의 특성중의 하나인 작업조건(function specification)에 따른 무오차점(precision point)의 최대 개수를 알아내는 프로그램 을 개발하여 이로써 얻은 정보를 또 다른 데이타베이스에 저장하였다. 이와같이 구축 된 데이터베이스들로부터 설계자의 요구에 적합한 기구를 선택하여 형태합성 문제를 해결하였다.

• 동의생리병리학회지
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• 제17권5호
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• pp.1315-1320
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• 2003

The purpose of this research was to investigate effects of Bambusae Caulis in Liquamen (BCL) on the synthesis of basement membrane proteins during proliferation and differentiation of 3T3-L1 cells. BCL has been used to relieve the cough and asthma, and remove phlegm in traditional oriental medicines. In recent years. it was studied for its antiinflammatory, antiallergenic. immune-modulating and anticarcinogenic capabilities. We have previously observed that glycyrrhizin stimulates the adipose conversion of 3T3-L1 cells. To investigate effects of BCL on the basement membrane proteins during proliferation and differentiation of 3T3-L1 cells, we have analyzed synthetic amounts of basement membrane components such as type IV collagen and BM40. BCL stimulated the synthesis and secretion of type IV collagen from both 3T3-L1 preadipocytes and adipocytes. The synthesis and secretion of BM40 was not affected by BCL. The continuous addition of BCL markedly stimulated cell growth and increased cell density. These results suggest an important role for type IV collagen in adipocyte differentiation.

• 한국수소및신에너지학회논문집
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• 제15권2호
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• pp.119-128
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• 2004

DME(Dimethyl Ether) was directly produced from the synthesis gas using the slurry phase reactor. The catalyst for DME production prepared two types (A type; Cu:Zn:Al=57:33:10, B type; Cu:Zn:Al=40:45:15, molar ratio). It was evaluated for the effect of the reaction medium oil using the small size slurry phase reactor. DME production yield and the methanol selectivity decreased in the order: n-hexadecane oil> mineral oil> therminol oil. The long-term test of DME production was carried out using A and B type catalyst, and n-hexadecane oil and mineral oil, respectively. It was confirmed that the use of A type for the catalyst and n-hexadecane for the reaction medium oil was very useful for the viewpoint of the DME production form the synthesis gas.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.804-819
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• 2003

It has been known that adenine is a very important material in living cells. Because, adenine is a member of nucleotide base, so it takes part in DNA, RNA and ATP synthesis. There are many reports that adenine participated in ingredients, especially DNA, RNA, NADH and ATP, affect on the cell. As well adenosine, conjugated adenine to glycoside, was known to anti-wrinkle compound. But there is no report whether adenine shows a good effect on the skin, especially anti-wrinkle. So, in this study, we tested whether adenine affects cell proliferation, collagen synthesis, collagenase synthesis inhibition in human dermal fibroblasts. In addition, we performed clinical study with adenine cream. Cell proliferation effect was tested by MTT assay. Collagen and collagenase synthesis were measured by Immunoassay with ELISA kit. Clinical study was performed by IECK according to KFDA Functional Cosmetic method. The results of cell proliferation show that 10$^{-6}$ ~10$^{-8}$ ％ of adenine increases cell proliferation about 50 ％ compare with non-treated control. At 10$^{-7}$ ~10$^{-10}$ ％, adenine increases type I collagen synthesis about 50％, decreases type I collagenase about 22％ compare with non-treated control. The results of clinical study show that 0.05％ adenine treated group reduces wrinkle significantly compare with placebo treated group. Therefore adenine may be a new anti-wrinkle candidate, through increases cell proliferation and collagen synthesis dramatically. And it decreases collagenase synthesis. So adenine could be used as a new anti-wrinkle agent.

• 미생물학회지
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• 제13권3호
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• pp.123-137
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• 1975

Sexual reproduction of paramecia have been accomplished through conjugation between individuals which have opposite mating type substances on their cilia when they were starved. Using selfing clone in which mating takes place, I examined whether a mating type change in indicidual cells required new protein and new mRNA synthesis or not and also shether there is a precursor relationship between both of the complementary mating type substances in their synthetic pathway. I found that 1. Mating type change needs new protein(s) and new mRNA synthesis. 2. Mating type substances are synthesized sequentially from mating type XIII to XIV 3. There might be a common precursor pool from which the mating type XIII substnace is synthesized and then complementary mating type XIV is fromed by addition of small group to the mating type XIII substance.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -2
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• pp.623-626
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• 2000

The purpose of this paper is to find an efficient solution for multiple constant multiplication (MCM) problem. Since the circuit structure can be represented as a directed acyclic graph, evolutionary computing is considered as an effective tool for optimization of circuit synthesis. In this paper, we propose a stack type operator as a chromosome element to synthesize a directed acyclic graph efficiently. This type of chromosome can represent a graph structure with a set of simple symbols and so we can employ the similar method to a conventional GA.