• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.225-232
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• 2004

Recently, there has been a rapid development in computer technology, which has in turn led to develop the automated welding system using Artificial Intelligence (AI). However, the automated welding system has not been achieved duo to difficulties of the control and sensor technologies. In this paper, the classification of the optimized bead geometry such as bead width, height penetration and bead area in the Gas Metal Arc (GMA) welding with fuzzy logic is presented. The fuzzy C-Means algorithm (FCM), which is best known an unsupervised fuzzy clustering algorithm is employed here to analysis the specimen of the bead geometry. Then the quality of the GMA welding can be classified by this fuzzy clustering technique and the choice for obtaining the optimal bead geometry can also be determined.

• 한국가스학회지
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• 제19권2호
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• pp.45-53
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• 2015

외관검사공정의 성능을 개선하기 위하여 기존의 자동외관검사장비 및 인간검사원에 추가하여 새로이 나이브 베이즈 분류기를 이용한 공정 구성을 개발하였다. 나이브 베이즈 분류기를 공정에 적용함으로써 불량의 유출 및 인간검사원의 작업량을 동시에 개선할 수 있다. 이때 분류기의 판정기준으로 기존의 MAP 방법 대신 AMPB 방법을 제안하여 적용하였다. 카메라모듈 용 필터 제품을 이용한 실험 결과 유출율 1.14%, 인간검사원 작업량 비율 75.5% 수준에서 공정을 구성하는 것이 가능함을 확인할 수 있었다. 본 연구의 결과는 검사 장비 및 인간이 협업을 하여 수행하는 타 공정 - 가스 누출 탐지 - 등에도 적용될 수 있다는 것에 넓은 범위에서의 의의가 있다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.479-482
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• 2003

We propose a real time gas monitoring system for classifying various gases with different concentrations. Using thermal modulation of operating temperature of two sensors, we extract patterns of gases from the voltage across the load resistance. We adopt the relative resistance as a pre-processing method and an ART2 neural network as a pattern recognition method. The proposed method has been implemented in a real time embedded system with tin oxide gas sensors, TGS 2611, 2602 and an MSP430 ultra-low power microcontroller in the test chamber.

• 환경영향평가
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• 제22권3호
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• pp.195-201
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• 2013

Local governments are establishing their own greenhouse gas reduction goal and are playing a important role to respond to climatic changes. However, there are difficulties in quantitative analyses such as estimation of future greenhouse gas emission and computation of reduction potential, which are procedures required to establish mid to long term strategies to realize of low carbon society by each local governments. Also, reduction measures must reflect characteristics of each local government, since the reduction power of each local government can differ according to characteristics of each. In order to establish strategies that reflect characteristics of local governments, types of greenhouse gas emission from cities were classified largely into residential city, commercial city, residential commercial city, agriculture and fishery city, convergence city, and industrial city. As a result of analyzing basic unit of greenhouse gas emission by local government during 2007 in terms of per population, household and GRDP based on the type classification, significant results were deduced for each type. To manage the amount of the national greenhouse gas, reduction measures should be focused on the local governments that emits more than the average of each type's GHG emission.

• 한국재료학회지
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• 제16권10호
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• pp.633-638
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• 2006

Silica powders with spherical shape and narrow size distribution were prepared by large-scale ultrasonic spray pyrolysis applying the droplet classification apparatus. On the other hand, silica powders prepared by large-scale ultrasonic spray pyrolysis without droplet classification apparatus had broad size distribution. Droplet classification apparatus used in this paper applied the principles of cyclone and dispersion plate with small holes. The droplets formed from the ultrasonic spray generator applying the droplet classification apparatus had narrow size distribution. The droplets with fine and large sizes were eliminated by droplet classification apparatus. The optimum flow rate of the carrier gas and diameter of the hole of the dispersion plate were studied to reduce the size distribution of the silica powders prepared by large-scale ultrasonic spray pyrolysis. The size distribution of the silica powders prepared by large-scale ultrasonic spray pyrolysis at the optimum preparation conditions was 0.76.

• 대한조선학회논문집
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• 제54권1호
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• pp.1-9
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• 2017

LNG has significant advantages in regard to environmental aspects comparing with conventional fuel oil. In fact, it is estimated that NOx and SOx emission can be reduced by about 90% and 100%, respectively in case of using LNG as a fuel. LNG-fuelled ship has been considered to be the best option both from an environmental and an economic point of view. Along with these trends, some major shipyards and Classification Societies have started to carry out the risk-based system design for LNG-fuelled ship such as passenger ship, platform supply vessel and large container vessel etc. However, new conceptual gas fuelled ship has high risk level compared with vessel using traditional crude oil especially in view of gas explosion accident. Therefore safety area where installed fuel gas supply system is required risk based system design with special considerations. On this paper, the entire process necessary for the quantitative risk analysis was explained to meet the satisfactory safety level of gas fuelled ship.

• 한국화재조사학회논문지
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• 제11권1호
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• pp.1-8
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• 2008

가스연료는 사업체, 가정 등에서 사용이 증가하고 있으며, 이로 인한 사고위험도도 증가추세 이며, 사고원인 또한 다양하게 나타나고 있다. 가스사고를 원인(취급부주의, 제품불량 등), 형태(화재, 폭발, 누출 등), 피해등급(1,2,3,4급), 사상자(사망, 중상, 경상)로 분류하여 설명하였다. 가스연료 중 가정에서 많이 사용되는 LP가스 시설은 가스용기, 압력조정기, 호스, 중간밸브, 연소기로 크게 구분할 수 있으며, 이 구성요소 중의 어떤 부분에서 취급부주의, 제품불량 등의 원인에 의해 화재 및 폭발 등이 발생할 수 있다. 따라서 사고 발생시 과거화재사례에 대한 연구 및 화재조사 시 착안사항을 참고하여 정확한 원인이 규명되어야 한다.

• 대한안전경영과학회지
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• 제4권4호
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• pp.15-26
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• 2002

The quantitative evaluation method of the safety management cost was suggested to prevent a gas accident as a major industrial accident. In a gas governor station, process risk assessments such as the fault tree analysis(FTA) and the consequence analysis were performed. Based on process risk assessments, potential accident costs were estimated and the cost-benefit analysis(CBA) was performed. From the cost-benefit analysis for five classification items of safety management cost, the order of the cost/benefit ratio was estimated.

• 한국광학회:학술대회논문집
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• 한국광학회 1989년도 제4회 파동 및 레이저 학술발표회 4th Conference on Waves and lasers 논문집 - 한국광학회
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• pp.39-42
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• 1989

The limitations of high-power electrical lasers due to heating of the gas and the instability of the glow discharge can be alleviated by the flow of the lasing medium. In order to achieve high power and efficient laser, we are developing a fast-axial flow CO2 laser. We describe here the classification of gas-discharge CO2 lasers according to the cooling methods of the lasing medium and the design features of the fast-axial flow CO2 laser.

• 한국화재조사학회논문지
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• 제11권1호
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• pp.59-65
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• 2008

각종 화재사고 분류 중 대표적으로 나타나는 가스사고는 그 형태와 원인이 다양하다고 할 수 있다. 가스사용량은 사용가구수가 증가와 사용 장소 및 가스기기의 다양화로 증가하고 있으며, 2007년도 가스사용량은 35,078천톤으로서 연평균 9.4%증가하였다. 가스사고는 95년 557건을 최고로 하여 2007년도에는 123건 발생하여 연평균 11.5%감소되었다. 가스의 종류에 따른 사고건수는 LP가스의 경우 전체 가스사고중 약 80%를 차지하고, 도시가스와 고압가스가 약 20%를 차지하고 있다. LP가 많았고, 특히 공급자부주의에 의한 사고가 끊이지 않고 증가하고 있는 추세이다. 가스사고는 사용자취급부주의, 공급자 취급부주의, 시공불량 및 노후제품으로부터 사고가 발생하여 인명과 재산피해가 발생하고 있다. 본 논문에서는 가스사고의 분류와 형태별, 원인별, 지역별 등에 대한 사고분포를 통해 가스사고의 원인에 대한 이해를 하고 가스안전사고를 예방하는 자료로 활용되도록 하였다.