• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.211-213
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• 2014

Simultaneous measurements of planar laser-induced fluorescence (PLIF) of OH radicals and particle image velocimetry (PIV) were used to investigate the strain rates and OH structure characteristics of turbulent syngas non-premixed jet flames close to blowoff. Mean values of the maximum principal strain rate on OH layer decreases with the axial distance, and its standard deviation is significantly large upstream. Strain rate on stabilization region of the stable flame is only about a half of that of the flame near blowoff.

• 한국초등수학교육학회지
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• 제1권1호
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• pp.1-16
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• 1997

문제해결력 신장을 위해서는 아동 개개인에게 문제 해결 전략을 체득시키고, 의도적인 문제 해결 과정과 개별적인 문제 해결 경험의 기회가 주어져야 한다. 개별화를 지향하는 학습 지도 방안을 구성하기 위하여 문제 해결 학습 활동 형태를 개별 학습 활동 형태, 집단 학습을 곁들인 개별 학습 활동 형태, 팀 티칭의 형태로 구분하였다. 이러한 학습 활동을 지원하기 위하여 문제해결 지도 중점별 교수 학습 활동 흐름을 구체화한 후 구체물이나 반구체물 조작 방법과 여러 가지 문제 해결 전략 및 문제 해결 과정을 개별 지도하는 수업을 실시하여 그 결과를 분석하였다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.55-58
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• 2012

EINOx scaling for $H_2/CO$ non-premixed turbulent jet flame was conducted. NOx concentration and flame length were measured simultaneously with varying flow conditions. Flame length increases with Reynolds number which means the flames in buoyancy-momentum transition region. We assessed the previous Chen & Driscoll's scaling with present results. However, the scaling cannot satisfy the present results. We proposed new scaling which is addressed the simplified flame residence time. The new scaling satisfies the results of $H_2/CO$ syngas flame as well as pure hydrogen flames.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
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• pp.259-261
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• 2012

The effect of fuel composition and coaxial air on the nitrogen oxide emission index was studied in a non-premixed turbulent jet flame. Validity of experimental setup and methodology is checked. The NOx emission trend is similar with previous works in hydrogen flame, but it's not well in $H_2/CO$ flame. Normalized EINOx scaling with modified $S_G$ applying near-field concept was conducted. Experimental data don't collapse single correlation curve, but partially same trend is observed in all cases.

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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• 한국정보과학회언어공학연구회 2023년도 제35회 한글 및 한국어 정보처리 학술대회
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• pp.581-585
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• 2023

Question Answering(QA)은 질문과 문맥에 대한 정보를 토대로 적절한 답변을 도출하는 작업이다. 이때 입력으로 주어지는 문맥 텍스트는 대부분 길기 때문에 QA 모델은 이 정보를 처리하기 위해 상당한 컴퓨팅 자원이 필요하다. 이 문제를 해결하기 위해 본 논문에서는 요약 모델을 활용한 요약 기반 QA 모델 프레임워크를 제안한다. 이를 통해 문맥 정보를 효과적으로 요약하면서도 QA 모델의 컴퓨팅 비용을 줄이고 성능을 유지하는 것을 목표로 한다.

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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• 한국정보과학회언어공학연구회 2023년도 제35회 한글 및 한국어 정보처리 학술대회
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• pp.185-189
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• 2023

Text to SPARQL은 지식 그래프 기반 질의응답의 한 형태로 자연어 질문을 지식 그래프 검색 쿼리로 변환하는 태스크이다. SPARQL 쿼리는 지식 그래프의 정보를 기반으로 작성되어야 하기 때문에 기존 언어 모델을 통한 코드 생성방법으로는 잘 동작하지 않는다. 이에 우리는 거대 언어 모델을 활용하여 Text to SPARQL를 해결하기 위해 프롬프트에 지식 그래프의 정보를 증강시켜주는 방법론을 제안한다. 이에 더하여 다국어 정보 활용에 대한 영향을 검증하기 위해 한국어, 영어 각각의 레이블을 교차적으로 실험하였다. 추가로 한국어 Text to SPARQL 실험을 위하여 대표적인 Text to SPARQL 벤치마크 데이터셋 QALD-10을 한국어로 번역하여 공개하였다. 위 데이터를 이용해 지식 증강 프롬프팅의 효과를 실험적으로 입증하였다.

• 제어로봇시스템학회논문지
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• 제21권3호
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• pp.224-232
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• 2015

In order to develop an active safety system which avoids or mitigates collisions with preceding vehicles such as autonomous emergency braking (AEB), accurate state estimation of the nearby vehicles is very important. In this paper, an algorithm is proposed using 3 dynamic models to better estimate the state of a vehicle which has various dynamic patterns in both longitudinal and lateral direction. In particular, the proposed algorithm is based on the Interacting Multiple Model (IMM) method which employs three different dynamic models, in cruise mode, lateral maneuver mode and longitudinal maneuver mode. In addition, a Probabilistic Data Association Filter (PDAF) is utilized as a data association algorithm which can improve the reliability of the measurement under a clutter environment. In order to verify the performance of the proposed method, it is simulated in comparison with a Kalman filter method which employs a single dynamic model. Finally, the proposed method is validated using radar data obtained from the field test in the proving ground.

• 한국연소학회지
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• 제17권4호
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• pp.30-37
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• 2012

The flame lengths and NOx emission characteristics of syngas $H_2$/CO turbulent non-premixed jet flames were investigated. The flame length which is the main parameter governs NOx emission was studied for various syngas compositions. The flame length was compared with previous correlation between Froude number and flame height and it shows that they have good agreements. It was confirmed that the turbulent jet flames herein investigated are in the region of buoyancy-momentum transition. NOx emission was reduced with increased Reynolds number and CO contents in syngas fuel and with decreased fuel nozzle diameter which is attributed by decreased flame residence time. Previous EINOx scaling based on flame residence time of $L_f^3/(d_f^2U_f)$ satisfies only the jet flame in momentum-dominated region, not buoyancy-momentum transition region. The simplified flame residence time ($L_f/U_f$) was adopted in modified EINOx scaling. The modified scaling satisfies the jet flames not only in momentum-dominated region but in buoyancy-momentum transition region. The scaling is also satisfied with $H_2$/CO syngas jet flames.

• 한국연소학회지
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• 제22권1호
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• pp.32-38
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• 2017

This paper shows the dynamics of the Burke-Schumann flame. To show flame dynamics, this paper measures the flame surface and heat release rate. The flame shape is divided into three types with forcing frequencies. When the forcing frequency is lower than 120 Hz, the upper region of flame is cut. The flame is stagnant with 220 to 280 Hz forcing frequencies. The rest conditions of forcing frequencies make the connected wave shape of flame. The heat release rate is expressed by the flame transfer function. The gain of the flame transfer function is similar with the oscillation magnitude of the flame area except for flame cutting conditions. The flame is cut because the fuel is not supplied to upper flame region.

• 한국IT서비스학회지
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• 제21권3호
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• pp.43-61
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• 2022

With the development of information technology, IT-based services in public administration has become more indispensable. As a result, the importance of IT maintenance projects to improve the efficiency of IT services and secure service levels is growing. Due to the nature of IT maintenance projects on local government, which mainly involve small and medium-sized IT companies in the region, business participating companies often do not have an appropriate methodology for service quality management. To solve this situation, the government has prepared a service level agreements (SLAs) that can be applied to IT maintenance projects. However, most local governments do not use SLAs for IT maintenance projects. As a result, various problems such as failure of the IT maintenance project or deterioration of quality are occurring Thus, this paper suggested major indexes to evaluate which service factors affect the efficient operation of information systems and the improvement of service quality in IT maintenance projects of local governments and analyzed the importance of indexes based on AHP method. Using this research method, this study found the theoretical implications on the outsourcing service of IT maintenance.