• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.194.3-194.3
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• 2003

As a part of an ongoing collaborative program to discover novel bioactive components of plant origin, the stem barks of Kalopanax septemlobus were extracted with MeOH, and successively partitioned with CH$_2$Cl$_2$, EtOAc, BuOH and water. Repeated column chromatographic separation of the CH$_2$Cl$_2$ fraction resulted in the isolation of four compounds. Their structures were identified as vladinol E (1), (-)-simulanol｛4-［3-hydroxymethyl-5-((E)-3-hydroxypropenyl)-7-methoxy-2,3-dihydrobenzofuran-2-yl］-2,6-dimethoxy-phenol｝ (2), vladinol F (3), and (${\pm}$)-secoisolariciresinol (4). This is the first report on the isolation of these compounds from Kalopanax species.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1998년도 PROCEEDINGS OF THE 14TH KACG TECHNICAL MEETING AND THE 5TH KOREA-JAPAN EMGS (ELECTRONIC MATERIALS GROWTH SYMPOSIUM)
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• pp.87-90
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• 1998

ABSTRACT- we have analyzed the effect of microstructure and interface conditions on the anisotropic exchange filelds of NiO/NiFe bilayers. The NiO films were deposited by R.F. magentron sputtering. By using different atgon pressure NiO Films, Grain Size And Surface Roughness Of NiO can be manipulated. The exchange field is enhanced in the small granined NiO And This Increment Is Based On The Formation Of Small Domains In NiO

• 대한설비공학회지:설비저널
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• 제7권1호
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• pp.13-19
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• 1978

An experiment has been performed of find a temperature distribution of the circulating fluid in a packed bed thermal storage system when the inlet fluid temperature is constant. The thermal storage system is a specific-heat type in which the circulating fluid, hot air, exchanges heat directly with the heat storage materials, glass balls, in a heat storage bin. An empirical equation which includes two dimensionless variables $t^*\;and\;T_f^*$, is obtained. Also, heat storage efficiency and heat storage capacity are calculated from this equation, The heat transfer coefficient calculated by the suggested equation was compared with the value determined by the existing empirical equation.

• 한국막학회:학술대회논문집
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• 한국막학회 1997년도 제5회 하계 Workshop (97 한,카 국제공동 Workshop, 고도 수처리를 위한 막분리 공정)
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• pp.143-158
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• 1997

Electrochemical deionization (EDI) offers continuous demineralization at higher water recovery rates (>90%), compared with mixed bed ion exchange, and without the use of chemical regenerants and the associated production of saline waste water. Although EDI technology has been used in some power generation applications, its wider application requires the satisfactory resolution of outstanding capital cost and performance issues. This paper reports on the field evaluation of a new cost-effective EDI technology in a power generation application. The E-Cell System$^{TM}$, which became commercially available in the fourth quarter of 1996, consists of a rugged, modular system, based on a new high-performance EDI stack. Starting in May 1996, a 100 gpm modular EDI pilot system, rated for operation at 100 psi, was evaluated at the TVA Brown's Ferry Nuclear Plant. The feed consisted of Reverse Osmosis (RO) permeate with a conductivity of 4-7 $\mu$S/cm. The pilot system reliably produced 17.8-18.0 M$\Omega$.cm water under design operating conditions, independent. Silica levels were reduced from ca. 50 ppb to 4 ppb, while TOC levels were reduced from ca. 120 ppb to 30 ppb.

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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• 한국정보과학회언어공학연구회 2019년도 제31회 한글 및 한국어 정보처리 학술대회
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• pp.78-80
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• 2019

개체명 인식 연구에서 우수한 성능을 보이고 있는 bi-LSTM-CRFs 모델은 처리 속도가 느린 단점이 있고, CNN-CRFs 모델은 한국어 말뭉치를 사용하여 제대로 분석되지 않았다. 본 논문에서는 한국어 개체명 인식 말뭉치를 이용한 CNN-CRFs 모델의 음절 단위 한국어 개체명 인식 방법을 제안한다. 실험 결과 bi-LSTM-CRFs 모델보다 CNN-CRFs 모델의 F1 score가 0.4% 높았고, 27.5% 빠른 처리 속도를 보였다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2024년도 춘계학술발표대회
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• pp.739-740
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• 2024

본 연구에서는 음성과 텍스트라는 두 가지 모달리티의 데이터를 효과적으로 결합함으로써, 감정 분류의 정확도를 향상시키는 새로운 멀티모달 모델 학습 방법을 제안한다. 이를 위해 음성 데이터로부터 HuBERT 및 MFCC(Mel-Frequency Cepstral Coefficients)기법을 통해 추출한 특징 벡터와 텍스트 데이터로부터 RoBERTa를 통해 추출한 특징 벡터를 결합하여 감정을 분류한다. 실험 결과, 제안한 멀티모달 모델은 F1-Score 92.30으로 유니모달 접근 방식에 비해 우수한 성능 향상을 보였다.

• Bulletin of the Korean Chemical Society
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• 제23권2호
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• pp.301-308
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• 2002

As part of perfluorocarbon (PFC) tracer release experiment conducted at the western coastal area of Korea in February 2001, the background concentration level of perfluorocarbons (PFCs) in the atmosphere was determined by gas chromatography with electron capture detector. Prior to the PFC tracer release experiment in the field, air samples were collected using active samplers and the background concentrations of PFCs were determined. The concentrations of perfluoromethylcyclohexane ($C_7F_{14}$, PMCH) in the western coastal area of Korea were in the range of 5.8-8.7 fL/L. The mean concentration of the PMCH in the region exhibited no significant spatial and temporal variations. This concentration level is somewhat higher and has larger standard deviation than those of studies previously conducted in USA and Europe on the background concentration levels of PFCs. Because the background concentration of PMCH in Korea is still very low and consistent temporally and spatially, the PMCH tracer can be used suitably for the studies of long-range atmospheric transport.

• 로봇학회논문지
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• 제14권3호
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• pp.179-185
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• 2019

This paper presents cable-hydraulic driven 3DoF (Degree-of-Freedom) manipulator for cooperative robot with high output/low inertia and enhancing lager workspace of hydraulic manipulator. Hydraulic actuation could be solution to design more higher output manipulator than the one of electric motor actuation due to install actuation source and robot joint separated. In spite of this advantage, the conventional hydraulic driven manipulator using cylinder or vane actuator is not suitable for the candidate of cooperative robot because smaller workspace owing to small RoM (Range of Motion) hydraulic actuator. In this paper, we propose 3DoF manipulator with cable-hydraulic actuation which is more larger ratio of payload-to-weight than the one of conventional cooperative manipulator and larger workspace than the one of existing hydraulic driven manipulator. The performance of proposed manipulator was demonstrated by the experiments for confirming overall workspace task, high payload operation task under worst situation and comparing repeatability between developed manipulator and existed cooperative robots. The results of experiments showed that the appropriate performance of proposed manipulator for cooperative robot.

• Membrane and Water Treatment
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• 제3권3호
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• pp.169-179
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• 2012

One of the major limitations in the use of commercial aromatic polyamide thin film composite (TFC) reverse osmosis (RO) membranes is to maintain high performance over a long period of operation, due to the sensitivity of polyamide (PA) skin layer to oxidizing agents, such as chlorine, even at very low concentrations in feed water. This article reports surface modification of a commercial TFC RO membrane (BW30-Dow Filmtec) by covering it with a thin film of poly(vinyl alcohol) (PVA) crosslinked with glutaraldehyde (GA) to improve its resistance to chlorine. Crosslinking reaction was carried out at 25 and $40^{\circ}C$ by using PVA 1.0 wt.% solutions at different GA/PVA mass ratio, namely 0.0022, 0.0043 and 0.013. Water swelling measurements indicated a maximum crosslinking density for PVA films prepared at $40^{\circ}C$ and GA/PVA 0.0043. ATR-FTIR and TGA analysis confirmed the reaction between GA and PVA. SEM images of the original and modified membranes were used to evaluate the surface coating. Chlorine resistance of original and modified membranes was evaluated by exposing it to an oxidant solution (NaClO 300 mg/L, NaCl 2,000 mg/L, pH 9.5) and measuring water permeability and salt rejection during more than 100 h period. The surface modification effectively was demonstrated by increasing the chlorine resistance of PA commercial membrane from 1,000 ppm.h to more than 15.000 ppm.h.

• 정보관리학회지
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• 제40권2호
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• pp.115-135
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• 2023

본 연구는 단행본, 학술지, 보고서 등 다양한 종류의 발간물로 구성된 연구보고서의 참고문헌 데이터베이스를 효율적으로 구축하기 위한 것으로 딥러닝 언어 모델을 이용하여 참고문헌의 자동추출 성능을 비교 분석하고자 한다. 연구보고서는 학술지와는 다르게 기관마다 양식이 상이하여 참고문헌 자동추출에 어려움이 있다. 본 연구에서는 참고문헌 자동추출에 널리 사용되는 연구인 메타데이터 추출과 더불어 참고문헌과 참고문헌이 아닌 문구가 섞여 있는 환경에서 참고문헌만을 분리해내는 원문 분리 연구를 통해 이 문제를 해결하였다. 자동 추출 모델을 구축하기 위해 특정 연구기관의 연구보고서 내 참고문헌셋, 학술지 유형의 참고문헌셋, 학술지 참고문헌과 비참고문헌 문구를 병합한 데이터셋을 구성했고, 딥러닝 언어 모델인 RoBERTa+CRF와 ChatGPT를 학습시켜 메타데이터 추출과 자료유형 구분 및 원문 분리 성능을 측정하였다. 그 결과 F1-score 기준 메타데이터 추출 최대 95.41%, 자료유형 구분 및 원문 분리 최대 98.91% 성능을 달성하는 등 유의미한 결과를 얻었다. 이를 통해 비참고문헌 문구가 포함된 연구보고서의 참고문헌 추출에 대한 딥러닝 언어 모델과 데이터셋 유형별 참고문헌 구축 방향을 제안하였다.