• 세라미스트
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• 제21권4호
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• pp.378-387
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• 2018

The optimal fabrication conditions for $Gd_{0.1}Ce_{0.9}O_{2-{\delta}}$(GDC) buffer layer and $La_{0.6}Sr_{0.4}Co_{0.2}Fe_{0.8}O_{3-{\delta}}$ (LSCF) cathode on 1mol% $CeO_2-10mol%\;Sc_2O_3$ stabilized $ZrO_2$ (CeScSZ) electrolyte were investigated for application of IT-SOFCs. GDC buffer layer was used in order to prevent undesired chemical reactions between LSCF and CeScSZ. These experiments were carried out with $5{\times}5cm^2$ anode supported unit cells to investigate the tendencies of electrochemical performance, Microstructure development and interface reaction between LSCF/GDC/CeScSZ along with the variations of GDC buffer layer thickness, sintering temperatures of GDC and LSCF were checked, respectively. Electrochemical performance was analyzed by DC current-voltage measurement and AC impedance spectroscopy. Microstructure and interface reaction were investigated by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Although the interfacial reaction between these materials could not be perfectly inhibited, We found that the cell, in which $6{\mu}m$ GDC interlayer sintered at $1200^{\circ}C$ and LSCF sintered at $1000^{\circ}C$ were applied, showed good interfacial adhesions and effective suppression of Sr, thereby resulting in fairly good performance with power density of $0.71W/cm^2$ at $800^{\circ}C$ and 0.7V.

• 한국패류학회지
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• 제29권3호
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• pp.171-179
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• 2013

동양달팽이의 arginine kinase 유전자는 염기서열 1065개로 이루어져있으며 355개의 아미노산으로 이루어져 있으며, BLAST 결과를 토대로 유사도가 높은 25개의 참고 서열과 동양달팽이의 arginine kinase의 아미노산 서열을 MEGA5 프로그램의 clustalW 모듈을 이용하여 multiple sequence alignment 를 수행한 결과, 연체동물문에 속하는 복족강 (5종), 두족강 (5종), 이매패강 (4종) 등에 속하는 생물들이 같은 군으로 묶였으며, 절지동물문 곤충강 에 속하는 나비목 (2종), 벌목 (1종), 노린재목 (2종) 등에 속하는 생물들이 같은 군으로 묶이고, 갑각강 (5종), 거미강 (1종) 에 속하는 생물들이 묶이는 것을 알 수 있었다. Psipred 소프트웨어를 통해 2D 구조를 비교 분석한 결과도 multiple align 및 phylodendrogram 결과와 밀접한 관계가 있음을 알 수 있었다. 시간에 따른 arginine kinase의 발현양상을 확인한 결과 control에 비하여 6시간에서 약 1.2배 정도 발현이 증가하는 것을 확인할 수 있었으며, 12시간이 지나면 점차 감소하는 것을 확인할 수 있었다. EST를 통해 밝혀진 N. samarangae 의 Ark 서열은 근연종들의 서열과 일치함을 알 수 있었으며, 본 연구 결과를 통해 무척추동물에서의 선천성 면역 관련 유전자 연구에 동양달팽이가 좋은 모델이 될 수 있음을 제시하고 있다.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 2002년도 학술대회지
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• pp.491-501
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• 2002

A cross-examination between KT&G Central Research Institute and Guangzhou Institute for Drug Control was carried out in order to select optimum conditions for extraction, separation and determination of ginsenosides in red ginseng and to propose a better method for the quantitative analysis of ginsenosides. The optimum extraction conditions of ginsenosides from red ginseng were as follows: the extraction solvent, $70\%$ methanol; the extraction temperature, $100^{\circ}C;$ the extraction time, 1 hour for once; and the repetition of extraction, twice. The optimum separation conditions of ginsenosides on the SepPak $C_{18}$ cartridge were as follows: the loaded amount, 0.4 g of methanol extract; the washing solvents, distilled water of 25 ml at first and then $30\%$ methanol of 25 ml; the elution solvent, $90\%$ methanol of 5 ml. The optimum HPLC conditions for the determination of ginsenosides were as follows: column, Lichrosorb $NH_2(25{\times}0.4cm,$ 5${\mu}m$, Merck Co.); mobile phase, a mixture of acetonitrile/water/isopropanol (80/5/15) and acetonitrile/water/isopropanol (80/20/15) with gradient system; and the detector, ELSD. On the basis of the optimum conditions a method for the quantitative analysis of ginsenosides were proposed and another cross-examination was carried out for the validation of the selected analytical method conditions. The coefficient of variances (CVs) on the contents of ginsenoside-$Rg_{1}$, -Re and $-Rb_1$ were lower than $3\%$ and the recovery rates of ginsenosides were $89.4\~95.7\%,$ which suggests that the above extraction and separation conditions may be reproducible and reasonable. For the selected HPLC/ELSD conditions, the CVs on the detector responses of ginsenoside-Rg, -Re and $-Rb_1$) were also lower than $3\%$, the regression coefficients for the calibration curves of ginsenosides were higher than 0.99 and two adjacent ginsenoside peaks were well separated, which suggests that the above HPLC/ELSD conditions may be good enough for the determination of ginsenosides.

• Elastomers and Composites
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• 제41권4호
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• pp.260-267
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• 2006

유기화 클레이(organically modified layered silicates)가 보강된 SBR 나노 복합체를 라텍스법(latex method)에 의해서 제조하였다. 유기화 MMT는 dodecylamine으로 유기화한 DA-MMT와 dimethyldodecylamine으로 유기화한 DDA-MMT의 두 가지를 제조하였다. 유기화 클레이의 층간거리와 분산도를 확인하기 위하여 XRD와 TEM촬영을 하였다 Na-MMT, DA-MMT, DDA-MMT의 XRD 회절 패턴을 분석한 결과 Na-MMT는 $2{\theta}=7.2^{\circ}$로써 층간거리가 $12.3{\AA}$, DA-MMT는 $2{\theta}=5.1^{\circ}$로 층간거리가 $17{\AA}$를 나타내었으며, DDA-MMT의 경우, 회절 피크는 $2{\theta}=4.8^{\circ}$로써. 층간거리는 $18.4{\AA}$으로 나타났다. 이는 DDA-MMT와 DA-MMT가 각각 5 phr 첨가된 SBR 나노 복합체의 TEM 결과에서도 확인할 수 있었다. SBR 나노 복합체에 filler system (carbon black/silica/OLS)을 적용 후 시편을 제조하였다. 제조된 시편의 동적 점탄성 평가 (DMTA)는 $-20^{\circ}C{\sim}80^{\circ}C$ 사이에서 이루어졌으며, loss factor (tan $\delta$)의 거동을 확인하였다. 그 결과, 타이어 트래드용 컴파운드를 대상으로 할 경우, 카본블랙과 실리카의 혼용비가 35:25일 때, 빗길 제동특성과 연비특성을 대변하는 $0^{\circ}C$와 $50{\sim}60^{\circ}C$에서의 tan $\delta$가 가장 우수함을 알 수 있었다. 또한 이 시스템에 실리카의 일정 부분을 DDA-MMT($0{\sim}10phr$)로 대체할 경우, $0^{\circ}C$의 tan $\delta$값은 높아지는 반면, $50{\sim}60^{\circ}C$의 tan $\delta$값은 감소하였다.

• 한국토양비료학회지
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• 제34권1호
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• pp.55-63
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• 2001

일리노이 옥수수 포장에서 질소비료의 적정 시용량 결정에는 작물 수량의 극대화와 더불어 질소 손실의 최소화가 고려 되어야 하는데 이를 위하여 질소 전문가체계(NES)가 개발되었다. NES는 전문가의 지식과 사고의 결정과정을 컴퓨터체계로 전환하는 Smart Element program에 의해 만들어졌다. NES는 현재 일리노이 옥수수포장에서 사용중인 생산성지수 (PI)와 토양중 유기물함량 (SOM) 및 시비전 질산태질소 함량 (PSNT)의 요인을 고려하여 시비수준을 결정하였는데 각각의 수준에 따라 49개의 rule 등을 사용하였다. NES는 시스템상에서 성공적으로 작동되었으며 3개의 토양특성 (PI, SOM, PSNT)를 입력하여 적정 시비량을 결정하였다. NES는 다른 시비량 결정 방법에 비해 환경에 대해 질소의 유입을 현저히 줄일 수 있었으며 모델에 대한 검증이 계속될 것이다. 그러나 이에 따른 수량의 감소를 보여, 질소 비료의 적정 시비량은 수량과 더불어 질소유실에 따른 환경 영향평가와 기타 다른 경제적 또는 토양의 물리화학적 요인이 고려되어야 하며 이 요인을 추가한 NES의 검증 및 개선방향이 모색되어야 할 것이다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제42권
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• pp.35.1-35.6
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• 2020

Background: Miescher's cheilitis granulomatosa (MCG) is a rare chronic inflammatory disease and is known as the monosymptomatic clinical form of Melkersson-Rosenthal syndrome (MRS). It is characterised by swelling of one or both lips and more frequently affects the upper lip. Histopathological findings show the presence of numerous inflammatory infiltrates and granuloma formations. Pharmacological treatments and surgery have provided results that are positive yet insufficiently stable in the long term. The clinical case described is of a 68-year-old female patient with a diagnosis of MCG of the upper lip. Case presentation: The patient was diagnosed and treated at the Oral Medicine and Oral Pathology outpatient clinic of Maxillofacial and Odontostomatology Unit, Fondazione Cà Granda IRCCS Ospedale Maggiore Policlinico. The patient was recommended localised treatments of photobiomodulation (PBM) using a diode laser with a 635 nm and 980 nm dual-wavelength (λ) approach, a 600-micron fibre, and a handpiece with a 1-cm-diameter lens at 300 mW. Three treatments a week were administered for four weeks for a total of 12 treatment sessions (T₁-T₁₂). After that, the patient had a long follow-up period of about 2 years. The therapeutic results were clear from the initial stages of treatment. There was an immediate, gradual, and consistent reduction in labial swelling. A reduction in the size of the lip by about 35% at T₁₀-T₁₂ was observed, returning the size and volume of the upper lip within the normal clinical range. The painful symptoms subsided after the seventh treatment (T₇). The histopathological check at 3 months and the follow-up in particular confirmed the disease was in remission with satisfactorily stable treatment results. Moreover, the patient did not use any other treatments on the area from the early laser treatments through to the end of the follow-up period. Conclusions: Our experience describes a clinical case of MCG treated with PBM and effectively resolved with a reduction of the lip swelling. The real success of the treatment emerged over time, showing that the tissue healing was stable. In absence of any collateral phenomena, this confirms the effective and documented therapeutic potential of PBM for chronic inflammatory infiltrates.

• 한국농림기상학회지
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• 제20권4호
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• pp.366-375
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• 2018

본 연구에서는 라이시미터를 이용하여 일천궁의 증발산량을 관측하였고, 그 자료를 분석하여 기상요소와 증발산량과의 관계를 조사하였다. 맑은 날이 지속된 4일간 라이시미터에서 관측된 증발산량은 일사량의 약 40%에 해당하는 것으로 관측되었으며, 증발산량 변화의 형태는 일출이 시작됨과 동시에 증가하였고 일몰과 함께 급격히 감소하여 일사량은 일천궁의 증발산량에 영향을 주는 중요한 인자로 나타났고 야간의 강한 풍속은 증발산량을 증가시켰으며, 일사량과 풍속이 증발산량 변화에 가장 큰 영향을 주는 요인이었다. $600W/m^2$ 이상의 일사량에서는 일천궁의 증발산량 증가가 없어 일천궁을 안정적으로 재배하기 위해서 잎 표면으로 입사되는 일사량의 조절이 필요한 것으로 조사되었다. 따라서 라이시미터는 야외에서 증발산량을 간단하면서도 정확하게 관측할 수 있는 방법임을 확인하였고, 추후 식물의 수분생리 및 적정 재배환경 구명에도 매우 유용할 것으로 사료된다.

• 한국해양공학회지
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• 제33권2호
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• pp.168-177
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• 2019

KRISO (Korea Research Institute of Ship & Ocean Engineering) started a project to develop the core algorithms for autonomous intervention using an underwater robot in 2017. This paper introduces the development of the robot platform for the core algorithms, which is an ROV (Remotely Operated Vehicle) type with one 7-function manipulator. Before the detailed design of the robot platform, the 7E-MINI arm of the ECA Group was selected as the manipulator. It is an electrical type, with a weight of 51 kg in air (30 kg in water) and a full reach of 1.4 m. To design a platform with a small size and light weight to fit in a water tank, the medium-size manipulator was placed on the center of platform, and the structural analysis of the body frame was conducted by ABAQUS. The robot had an IMU (Inertial Measurement Unit), a DVL (Doppler Velocity Log), and a depth sensor for measuring the underwater position and attitude. To control the robot motion, eight thrusters were installed, four for vertical and the rest for horizontal motion. The operation system was composed of an on-board control station and operation S/W. The former included devices such as a 300 VDC power supplier, Fiber-Optic (F/O) to Ethernet communication converter, and main control PC. The latter was developed using an ROS (Robot Operation System) based on Linux. The basic performance of the manufactured robot platform was verified through a water tank test, where the robot was manually operated using a joystick, and the robot motion and attitude variation that resulted from the manipulator movement were closely observed.

• Journal of Biosystems Engineering
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• 제43권4호
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• pp.285-295
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• 2018

Purpose: The aim of this study is to develop a three-wheel riding cultivator for improving the performance of the current four-wheel riding cultivators in the market. Methods: A prototype three-wheel riding cultivator with the rated power of 15.5-kW, a primary hydrostatic and a two-speed selective gear transmission shifts, front/rear three-wheel drive, a hydraulic wheel tread adjustment, and the mid-section attachment of the major implements was designed and constructed. Its specifications and basic performance are investigated. Results: The maximum speeds of the prototype at the low and high stages were measured to be approximately 7.31, and 11.29 km/h in forward travel, respectively, and approximately 3.60, and 6.37 km/h in rearward travel, respectively. The minimum ground clearance is shown to be 670 mm. The rotating speeds of the power takeoff (PTO) shaft at the low and high stages are shown to be approximately 795 and 1,140 rpm, respectively. The tread of the rear wheels, the minimum radius of turning, and the maximum lifting height of the parallel link device are measured to be within 1,320-1,720 mm, 2.80 m, and 390 mm, respectively. Approximately 25.3% and 74.7% of the total weight of the prototype are distributed in the front and rear wheels on flat ground, respectively. When the tread of rear wheels increased from 1,320 to 1,720 mm, the left and right static lateral overturning angles increased from $33.4^{\circ}$ to $39.1^{\circ}$ and from $29.0^{\circ}$ to $36.1^{\circ}$, respectively. Conclusions: The prototype three-wheel riding cultivator showed a wide range of travel and PTO speeds, high minimum ground clearance, small minimum radius of turning, and easy control of the rear wheel tread. Further, the easy observation of cultivating operations by mid-mounting the implements can improve quality of work. Therefore, the prototype is expected to contribute to the riding mechanization of cultivating operations for various upland crops in Korea.

• 멤브레인
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• 제29권4호
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• pp.223-230
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• 2019

본 논문에서는 이산화탄소 친화적인 PBEM-POEM (PBE) 공중합체를 기반으로 고분자 블렌드 분리막을 제조하는 방법을 제시한다. PBE 공중합체는 자유 라디칼 중합 반응을 통해 손쉽게 합성이 가능하며, 이를 상용 고분자인 PEG와 다양한 비율로 혼합하여 이산화탄소/질소 분리막을 제조하였다. 이산화탄소/질소 분리 성능을 테스트한 결과, PEG의 함량이 높을수록 이산화탄소 투과도는 감소하는 반면 이산화탄소/질소 선택도는 크게 증가하는 상충(trade-off) 관계가 나타났다. 그러나 PBE/PEG (9 : 1)과 PBE/PEG (7 : 3)을 비교하면 이산화탄소 투과도는 단지 8.3% 감소한 반면에 질소 투과도는 69.1%나 감소하였다. 따라서 이산화탄소/질소 선택도가 33.8에서 100.3으로 크게 증가하였다. 이것은 PBE 공중합체의 80%를 차지하는 POEM 사슬이 PEG와 상호작용하여 더욱 조밀한 구조가 되었기 때문이며, 이를 FT-IR, XRD, SEM 분석으로 확인하였다. PBE/PEG (7 : 3) 블렌드 막이 가장 최적의 기체 분리 성능을 가졌고, 이산화탄소투과도는 170.5 GPU, 이산화탄소/질소 선택도는 100.3이었다.