• 한국정보처리학회논문지
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• 제3권3호
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• pp.564-571
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• 1996

본 논문에서는 새로운 ASIC 구조로 최근에 관심을 모으고 있는 TLU형 FPGA를 위한 순차회로 기술 매핑에 관한 것이다. 본 고에서 제안하는 TLU형 FPGA를 위한 순차회로 기술 매핑방법은 먼저 6개 또는 7개의입력을가지는 조합 및 순차 노드에대해서 전처리 기를 사용하여 한 출력 CLB에매핑하고, 매핑안된나머지 중 순차회로합병 조건에 만족 하는 6개 혹은 7개 입력 변수를 갖는 노드부터 CLB에 매핑한다. 본 고에서 제안한 순차 회로 기술 매핑 방법이 간단하면서 만족스런 수행 시간과 결과를 얻었다. 여러개의 벤치마크 화로를 sis-pga(map_together 및 map_scparate)순차회로 합성 시스템과 비교 하였으며, 실험결과는 본 시스템이 sis-pga 보다 17% 이상 성능이 좋다는 결과를 보여 주고 있다.

• Toxicological Research
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• 제26권1호
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• pp.61-66
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• 2010

Retinoids have many beneficial effects on dermatological applications. But, retinoids cause skin irritation. In this study, the safety of retinoids was clarified via both primary skin irritation test in rabbits and sensitization study using an integrated model for the differentiation of chemical-induced allergic and irritant skin reaction (IMDS), an alternative method to sensitization test. The effects of retinoids on the change of ultraviolet A (UVA)-induced matrix metalloproteinase-1 (MMP-1) in human skin fibroblasts and the modulation of type-1 pN collagen synthesis in hairless mice were examined to clarify the anti-wrinkle effects. Alltrans retinol (t-ROL) and its derivative, all-trans retinoic acid (t-RA), showed mild skin irritation but did not induce the sensitization. t-ROL and t-RA exerted anti-wrinkle effects by inhibiting the UVA-induced MMP-1 in human skin fibroblasts and increasing the type-1 pN collagen synthesis in hairless mice. These findings suggest that retinoids do not induce the allergy, and show anti-wrinkle effects by decreasing MMP-1 activation and increasing collagen synthesis.

• Bulletin of the Korean Chemical Society
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• 제30권3호
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• pp.551-555
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• 2009

The ytterbium catalyst immobilized on the cross-linked poly(4-vinylpyridine/styrene) copolymer (P/S-Yb) was applied in the Mannich-type, three component one-pot synthesis of $\beta$-aminoketones. This catalytic system showed excellent catalytic activity and selectivity which resulted in the exclusive formation of $\beta$-aminoketone. The applicability of this immobilized catalyst system was shown by the reusability test and again highlighted by the synthesis of a $\beta$-aminoketone library using a broad range of substrates.

• 대한화학회지
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• 제63권6호
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• pp.435-439
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• 2019

An efficient one pot multicomponent synthesis of pyrimidinone derivatives of Biginelli type is described. 4-amino-6-aryl-pyrimidine-5-carbonitrile molecules were synthesized efficiently via three-component Biginelli-type condensation of aldehyde, malononitrile, and semicarbazone as urea substituent in the presence of a catalytic amount of PEG-400 as green medium under microwave irradiation. The reactions proceeded efficiently in the presence of microwave radiation to afford the desired products in good to excellent yields. Products have been confirmed by IR, and NMR spectral analysis. All the molecules were tested for their antimicrobial activity against E. coli, S. aureus, P. aeruginosa and C. tropicalis. Some of the compounds have shown moderate to good inhibition efficiency against both gram-positive and gram-negative bacteria. The potent activity was observed against the fungal species with minimum inhibition concentration 12.5 ㎍/mL.

• Bulletin of the Korean Chemical Society
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• 제35권7호
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• pp.1970-1972
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• 2014

A facile and efficient synthesis of dronedarone hydrochloride starting from commercially available 4-nitrophenol is described. This approach features a tandem-type synthesis of 3-carbonylated benzofuran involving cyclization of 2-ethynylphenol followed by $CO_2$ fixation at the 3-position of the benzofuran ring mediated by potassium carbonate without the addition of any transition metal catalyst.

• 한국세라믹학회지
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• 제40권2호
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• pp.132-138
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• 2003

출발물질의 종류와 몰비 혼합 방법, 숙성, 결정화 온도와 결정화 시간 등 제올라이트 입자를 합성하는 조건이 FAU 형 제올라이트의 입자크기에 미치는 영향을 연구하였다. 동일한 출발물질이라도 혼합 경로에 따라 생성물의 결정상이 달랐다. 일반적으로 숙성과정을 거친 경우, 특히 숙성온도가 낮은 쪽이 입자 크기가 작았다. 2단계의 혼합겔 제조 방법을 거치는 경우 결정화 기간은 크게 단축되고 입자 크기도 작아졌으나. 1단계에서 제조된 2종의 혼합겔을 모두 숙성하지 않는 경우에는 결정화 시간은 단축되지만, 입자크기는 작아지지 않았다. 액상규산나트륨과 알루민산나트륨, 수산화나트륨을 출발물질로 하여. 저농도와 고농도의 혼합겔을 1차 제조하고, 이 혼합겔을 각각 숙성하고 다시 혼합하여 숙성하는 방법으로 결정화 시간을 단축하고 평균입경 0.4$\mu$m. 비표면적 838 $m^2$/g의 우수한 특성을 가지는 FAU혈 제올라이트를 합성하였다.

• 한국세라믹학회지
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• 제32권7호
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• pp.777-782
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• 1995

The scale up production test for the hydrothermal synthesis of clay mineral from the anorthite, which is distributed in San Chung-District of Korea and called as the ground rock for halloysite-kaolin, has been investigated by using the gaitator type reactor. The automatic control system has been developed and applied for the more effective producibility and the reduction in the defect of this intermittent batch processing property, and finally for the feasibility of this system in actual use. It was observed that this agitator type reactor can reduce the synthesis reaction tme from 5 days to 3 days, only with the condition of 20rpm. The automatic control system could regulate the vessel temperature and pressure precisely at an optimum condition during the treatment. Therefore, from these test results the application-possibility for this system was found to be feasible in actual use.

• 한국균학회지
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• 제13권4호
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• pp.235-241
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• 1985

본 연구는, catabolic repression시킨 효모세포를 완전배지와 최소배지에서 derepression시켜, 배양시기 및 인산 첨가농도(free, limited, sufficient)에 따른 5종의 다당류 합성변화를 조사하였다. 그리고 다당류 합성과 무기폴리인산 축적량 및 인지질 합성 사이의 상관지수를 구하여 합성시 관련되는 유의한 정도를 검정하였다. 그 결과, 최소배지에서 catabolic derepression시킨 효모세포가, 완전배지에서 derepression시킨 세포에 비하여, glycogen의 합성이 발리 그리고 많이 일어났고, acid soluble glycogen type이 주된 함량을 나타내었으며, alkali soluble glycogen은 당이 많이 소모된 24시간 배양 후에 소량 나타났다. 무기인산 첨가정도에 따라 total glycogen합성이 일정한 비율로 빨리 그리고 높게 일어났다. Glucan의 합성에는 ALPase 중 ALPase "C"가 관련할 것으로 추정되었다. Mannan은 ezponential phase초기와 정체기때, acid soluble 분획은 정체기때 최대함량을 나타내었다. Mannan 합성과 poly-P "C"축적량 사이의 상관지수는 0.866, mannan합성과 인지질 사이의 상관지수는 0.726으로 나타나 매우 유의하였다.

• 한국전기전자재료학회논문지
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• 제25권6호
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• pp.481-485
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• 2012

ZnO nanowires were synthesized by hydrothermal technique. Prepared synthesis aqueous solutions were preserved by preheating in autoclave type synthesis equipment with various preheating time of 1 h difference. ITO-coated corning glass substrates deposited with AZO seed layers were then inserted in the preheated synthesis aqueous solutions and ZnO nanowires were grown for 180 min at $90^{\circ}C$. Density, length and aspect ratio of the grown ZnO nanowires were investigated. Composition, structural and optical properties of the grown ZnO nanowires were analyzed. Characteristics of the ZnO nanowires were comparatively studied in relation with $Zn^{2+}$ ion concentration measured directly after the preheating of synthesis aqueous solution.

• Applied Microscopy
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• 제26권3호
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• pp.379-388
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• 1996

Structure of premartensite in $Ti_{50}Ni_{49}Fe_1\;and\;Ti_{50}Ni_{50}$ prepared by self-propagating high temperature synthesis (SHS) method has been investigated by a detailed transmission electron microscopy. $Ti_{50}Ni_{49}Fe_1$ consists of microdomain area and needle type domain area. On the other hand, $Ti_{50}Ni_{50}$ consists of microdomain-free and microdomain area, and needle type domain area. Various types of extra superreflections, such as 1/2<100>, 1/2<110> and 1/4<210> type superreflection have been observed in the selected area electron diffractions from microdomain area. Such extra superreflections are due to transformation from B2 structure to distorted B2 structure or premartensite. The present study shows that incommensurate phase forms as an intermediate phase during martensitic transformation. Particularly, in Fe-free $Ti_{50}Ni_{50}$, two types of matrix phases have been observed, microdomain and microdomain-free area. Types of extra superreflections in $Ti_{50}Ni_{50}$ are different from those in $Ti_{50}Ni_{49}Fe_1$, i.e. 1/7<321> type superreflections have been observed, instead of 1/2<110>, 1/2<100>, 1/4<210> types in $Ti_{50}Ni_{49}Fe_1$.