• Transactions on Electrical and Electronic Materials
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• 제15권6호
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• pp.338-343
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• 2014

A $Fe_3O_4$-graphite nanofiber composite for use as an anode material was successfully synthesized by calcining $Fe_3O_4$ and graphite nanofiber (GNF) together in a $N_2$ atmosphere. Using this $Fe_3O_4$-GNF composite in a lithium ion battery resulted in a higher lithium storage capacity than that obtained using $Fe_3O_4$-graphite ($Fe_3O_4$-G). The $Fe_3O_4$-GNF (10 wt%) electrode exhibited a higher lithium ion diffusion coefficient ($2.29{\times}10^{-9}cm^2s^{-1}$) than did the $Fe_3O_4$-G (10%) ($3.17{\times}10^{-10}cm^2s^{-1}$). At a current density of $100mA\;g^{-1}$, the $Fe_3O_4$-GNF (10 wt%) anode showed a higher reversible capacity ($1,031mAh\;g^{-1}$) than did the $Fe_3O_4$-G (10%) anode ($799mAh\;g^{-1}$). Moreover, the $Fe_3O_4GNF$ electrodes showed good cycling performance without the addition of a conductive material.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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• pp.122-122
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• 1993

살균, 정균, 살진균, 정진균등의 효능이 있는 나프토퀴논꼴 화합물인 6-oxo-3, 4, 4a, 5-tetrahydro-3-hydroxy-2,2-dimethylnaphtho [1,2] pyran(1)과 그의 유도체인 9-methoxy-6-oxo-3, 4, 4a, 5-tetrahydro-3-hydroxy-2, 2-dimethylnaphtho [1,2] pyran(2), 8,9-dimethoxy-6-oxo-3, 4, 4a, 5-tetrahydro-3-hydroxy-2, 2-dimethylnaph-the [1,2] pyran(3), 9-bromomethyl-6-oxo-3, 4, 4a, 5-tetrahydro-3-hydroxy-2, 2-dimethyl-naphtho [1,2] pyran(4)와 8, 9-methylenedioxy-6-oxo-3, 4, 4a, 5-tetrahydro-3-hydroxy-2, 2-dimethylnaphtho [1,2] pyran(5)을 손쉽게 구할 수 있는 benzene, anisole, 1, 2-di-methoxybenzene, bromomethylbenzene, 1, 3-benzodioxole등을 원료로 하여 합성하는 것이 본 연구의 목적이다.

• 디지털산업정보학회논문지
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• 제18권4호
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• pp.31-40
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• 2022

YOLOv4 can be used for detecting parking vehicles in order to check a vehicle in out-door parking space. YOLOv4 has 9 anchor boxes in each of 13x13 grid cells for detecting a bounding box of object. Because anchor boxes are allocated based on each cell, there can be existed small observational error for detecting real objects due to the distance between neighboring cells. In this paper, we proposed YOLOv4 grid cell shift algorithm for improving the out-door parking vehicle detection accuracy. In order to get more chance for trying to object detection by reducing the errors between anchor boxes and real objects, grid cells over image can be shifted to vertical, horizontal or diagonal directions after YOLOv4 basic detection process. The experimental results show that a combined algorithm of a custom trained YOLOv4 and a cell shift algorithm has 96.6% detection accuracy compare to 94.6% of a custom trained YOLOv4 only for out door parking vehicle images.

• 한국자동차공학회논문집
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• 제6권2호
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• pp.1-11
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• 1998

The 4WS system is usually developed to improve the maneuverability at low speed and the straight line stability at high speed, but it is found to have the severe understeer characteristics at high speed. Therefore a 4WS vehicle requires to turn the steering wheel much more than a 2WS vehicle at high speeds even a driver goes through the same curved road. In this study, to enhance the cornering performance of the 4WS vehicle at high speed, a DYC 4WS system is proposed based on the nonlinear 4WS system and direct yaw moment control system. Especially the proposed DYC 4WS system is able to realize a zero side slip angle for vehicles and a cornering performance similar to the 2WS vehicle at high speed.

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2171-2177
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• 2011

Synthetic route has been developed for the synthesis of new (Z)-5-[4-(2-chloroquinolin-3-yl) methoxy]benzyl-idinethiazolidine-2,4-diones (6a-h) starting from 2-chloro-3-hydroxymethyl quinolines (2a-h). The hydroxy methyl quinolines on tosylation yielded (3a-h). Condensation of the tosyl intermediates with 4-hydroxy benzaldehydes has been carried in DMF in presence of $K_2CO_3$ and obtained 4-quinolinyl methoxy benzaldehydes (4a-h). Conveniently Knoevenagel condensation of quinolinyl methoxy benzaldehydes (4a-h) and 2, 4-thiazolidinedione (5) has been carried in PEG-400 in presence of L-proline and obtained better yields of the titled compounds (6a-h).

• 분석과학
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• 제15권1호
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• pp.31-35
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• 2002

${CIO_4}^-$ 이온만을 선택적으로 감지하는 새로운 수용체가 개발되었다. $[Pd(Me_4en)(Py_2S){\cdot}2ClO_4]_4$ ($Me_4en$ = N,N,N'N'-tetraethylethylenediamine; $Py_2S$ = 4,4'-dipyridyl sulfide) 착화합물에서 주-객 화학종 간의 고감도 작용력을 연구하였다. $Py_2S$의 피리딜 기는 온도, 농도, 매개체 등에 아주 민감한 두 가지의 셋트의 $^1H$ NMR, 공명 시그날을 보여주었다. 이러한 NMR 거동을 수용액에서 고리 사합체의 양이온과 ${CIO_4}^-$ 음이온 간의 정기적 인력에 의한 평형 때문인 것으로 해석되었다.

• KSBB Journal
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• 제14권4호
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• pp.422-428
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• 1999

Alcaligenes latus 유래의 phbC 유전자를 A. eutrophus에 재도입시킨 형질전환균주를 이용하여 높은 4HB 몰분율을 갖는 P(3HB-4HB)의 고농도 생산을 시도하였다. 형질전환균주는 총균체량, P(3HB-4HB) 농도, 그리고 축적률에서 모균주에 비해 다소 증가한 반면 P(3HB-4HB)내의 4HB 몰분율은 23.5 mol%로 모균주의 12.3 mol%에 비해 현저히 증가하였다. 이는 phbC유전자의 증폭으로 인해 해당과정에서 생성된 3HB와 전구물질인 ${\gamma}$-butyrolacton에서 전환된 4HB의 중합반응이 촉진되기 때문으로 사료된다. 또한 ${\gamma}$-butyrolacton의 농도 $Mg^{2-}$ 이온, 그리고 citrate 첨가량이 P(3HB-4HB)의 농도, 축적률, 그리고 4HB 몰분율에 미치는 영향을 검토하였다. P(3HB-4HB)내의 4HB 몰분율을 증대시키기 위하여 일반적으로 사용되는 2단계 배양법을 변형시켜 ${\gamma}$-butyrolacton과 citrate의 첨가시기를 늦춘 2단계 배양법을 활용하여 P(3HB-4HB)내의 4HB 몰분율을 61.0 mol%로 증가시킬 수 있었다. 또한 ${\gamma}$-butyrolacton의 첨가량을 조절하여 P(3HB-4HB)내의 4HB 몰분율이 92.0 mol%에 이르는 homopolymeric P(4HB)를 생산할 수 있었으며, 그 구조를 $^1$H-NMR을 통해 확인하였다.

• 한국안광학회지
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• 제19권1호
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• pp.69-77
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• 2014

목적: 본 연구는 플루오로로 치환된 아닐린 (2,4-difluoroaniline, 2,6-difluoroaniline, 3,4-difluoroaniline)을 첨가제로 사용한 기능성 콘택트렌즈를 제조한 후 각각의 물리 광학적 특성을 알아보았다. 방법: 친수성 하이드로젤 콘택트렌즈를 제조하기 위해 HEMA(2-hydroxyethylmethacrylate), NVP(N-vinyl pyrrolidone), MA(methacrylic acid), 교차결합제인 EGDMA(ethylene glycol dimethacrylate), 그리고 개시제인 AIBN(azobisisobutyronitrile)을 기본배합으로 한후, 불소로 치환된 aniline을 첨가하였다. 콘택트렌즈 제조방법은 cast mould법을 사용하여 공중합 하였으며, 제조된 콘택트렌즈는 0.9% NaCl normal saline에 완전히 침지시켜 24시간 수화 후 콘택트렌즈의 물리 광학적 특성을 측정하였다. 결과: 2,4-, 2,6- 및 3,4-difluoroaniline을 비율별로 첨가한 sample의 함수율을 측정한 결과, 첨가제의 비율이 증가할수록 함수율이 감소하는 경향을 나타내었으며, 굴절률의 경우 첨가제의 비율이 증가할수록 함수율과 반비례 하여 굴절률은 증가하는 경향을 나타내었다. 제조된 고분자에 대한 자외선 영역의 광투과율을 측정한 결과, 2,4-difluoroaniline를 첨가제로 사용한 경우, UV-B(9.8~51.4%), UV-A(58.8~79.2%) 그리고 visible transmittance(87.0~90.4%)의 투과율을 나타내었고, 2,6-difluoroaniline를 첨가제로 사용한 sample 렌즈는, UV-B(80.2~83.2%), UV-A(85.8~86.4%), 그리고 visible transmittance(90.8~91.4%)의 투과율을 나타내었다. 또한, 3,4-difluoroaniline를 첨가제로 사용한 고분자 렌즈는, UV-B(3.8~30.4%), UV-A(47.8%~74.4%) 그리고 visible transmittance(86.2~91.0%)의 투과율을 각각 나타내었다. 결론: 본 연구 결과를 통해, 2,4-difluoroaniline 그리고 3,4-difluoroaniline은 자외선 차단성을 지닌 착색 안의료용 렌즈 재료로 유용하게 사용될 수 있을 것으로 판단된다.

• Archives of Pharmacal Research
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• 제13권1호
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• pp.1-4
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• 1990

Reaction of propane-1, 3-sultone with amines gave N-substituted aminosulphonnic acids 2a-i, Dehydration of 2a-c with $POCI_3$ gave the corresponding sultams 3a-c. Propane-1, 3-sultone 1 reacted with tertury amines to give the betaiene salts 4-11. 2-4-Dimethyl-1, 3-butadiene-1, 4-sultone 12 condensed with amines to give N-substituted-2, 4-dimethyl-1, 3-butadiene-1, 4-sultames 13a and 13b. The reaction of 3a, 13a with hydrazine hydrate gave acid hydrazides 3d or 13c. Compounds 3d, 13c reacted with isocyanates to yield urea derivatives 14a-c, 15a-c.

• The Plant Pathology Journal
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• 제21권1호
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• pp.68-72
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• 2005

The production of antibiotic substances by Serratia plymuthica A21-4 was greatly enhanced by modifying components of a growth medium. When the minimal medium containing $K_2HPO_4$ 0.7%, $KH_2PO_4$ 0.2%, $(NH_4)_2SO_4$ 0.1%, $MgSO_4$ 0.01% was used as basal medium, the best carbon source for antibiotic production was glycerol and the most favorable nitrogen source was ammonium sulfate. The modified medium for antibiotic production also increased colonization ability of A21-4 on pepper root and in the rhizosphere soil. When the cells of A21-4 were suspended in modified medium, the population density of A21-4 on pepper root was 10-100 times higher than that suspended in 0.1 M $MgSO_4$. The population density of A21-4 on root did not decrease under $10^6$ cfu/groot up to 21 days after treatment although the inoculum of A21-4 was reduced to $10^7$ cell/ml. Similar tendency was also observed in the rhizosphere soil. Consequently, Phytophthora blight of pepper was successfully controlled by A21-4 with $10^7$ cell/ml suspended in the modified buffer solution instead of $10^9$ cfu/ml suspended in 0.1 M $MgSO_4$.