MMO 촉매와 CO 환원제에 의한 N₂O 분해에서 SO₂ 및 NH₃ 영향 연구

장길상,유경창,Chang, Kil Sang,You, Kyung-Chang 한국공업화학회 2009 공업화학 Vol.20 No.6

아산화질소($N_2O$)는 각종 화학산업의 제조공정은 물론 유기 및 화석연료의 각종 연소공정으로부터 배출되는 대표적 온실가스이다. 온난화 효과는 $CO_2$의 310배에 달하고 성층권에 도달해서는 오존층을 파괴하는 물질이지만 화학적으로 매우 안정하여 분해처리가 쉽지 않다. 각종 환원제를 이용한 SCR 반응도 대부분 $450^{\circ}C$ 이상의 높은 온도를 요구하며 NOx 존재시에는 활성이 현저하게 떨어지는 문제점을 가지고 있다. 본 연구는 $N_2O$ 분해촉매의 실용화를 위한 기초연구로 진행되었으며, hydrotalcite형 화합물 전구체로부터 얻어진 혼합금속산화물촉매(MMO)와 CO 환원제를 이용한 $N_2O$ 분해에서 $SO_2$ 및 $NH_3$ 등 성분이 촉매의 반응성과 내구성에 미치는 영향을 실험적으로 분석하여 실용화에 대비한 기본 자료로 삼고자 하였다. 본 실험에 사용된 MMO 촉매는 CO 환원제와 같이 사용할 경우 $N_2O$ 분해 성능이 크게 향상되어 $200^{\circ}C$ 근처에서도 완전히 분해되는 것으로 나타났다. 또한 $NH_3$ SCR에 의한 NOx 분해반응의 경우와 달리 $SO_2$ 영향이 치명적으로 나타나지 않았고, $NH_3$에 의한 효과도 미미하여 촉매의 활성점을 공유하는 불순물 성분 정도의 영향에 불과한 것으로 판단되었다. Nitrous oxide is a typical greenhouse gas which is produced from various organic or fossil fuel combustion processes as well as chemicals producing plants. $N_2O$ has a global worming potential of 310 times that of $CO_2$ on per molecule basis, and also acts as an ozone depleting material in the stratosphere. However, its removal is not easy for its chemical stability characteristics. Most SCR processes with several effective reducing agents generally require the operation temperature higher than $450^{\circ}C$, and the catalytic conversion becomes decreased significantly when NOx is present in the stream. Present experiments have been performed to obtain basic design data of actual application concerning the effects of $SO_2$ and $NH_3$ on the interim and long term activities of $N_2O$ reduction with CO over the mixed metal oxide (MMO) catalyst derived from a hydrotalcite-like compound precursor. The MMO catalysts used in the experiments, have shown prominent activities displaying full conversions of $N_2O$ near $200^{\circ}C$ when CO is introduced. The presence of $SO_2$ is considered to show no critical behavior as can be met in the $NH_3$ SCR DeNOx systems and the effect of $NH_3$ is considered to play as mere an impurity to share the active sites of the catalysts.

전자상거래 환경하에서 연관규칙과 이동경로를 발견하는 데이터마이닝 기법

장길상,이종섭 한국산업경영시스템학회 2003 한국산업경영시스템학회 학술대회 Vol.2003 No.춘계

We study data mining technique in an electronic commerce. Customers travel web pages in an shopping mall and they sometimes purchase products. It is important for a web master in a shopping mall to know customer"s purchasing patterns. We discover both association rules among customer"s purchasing products and customer"s traversal paths. We propose three phase mining technique to explore it. In the first phase, it find large items from sales database. In the second phase, it add to traversal paths. In the third phase, it discover associations rules from large items.

지식경영을 위한 사례기반추론 시스템의 구축 방법

장길상,김훈,유동일 한국정보처리학회 2007 정보처리학회지 Vol.14 No.5

이벤트 중심의 시나리오 기반 정보시스템 개발 방법론의 적용에 관한 사례 연구

장길상,이원조 대한안전경영과학회 2018 대한안전경영과학회지 Vol.20 No.2

Recently, most of the information system use environment is changing to GUI environment based on windows and web. Most of the development tools for building such a GUI-based information system support object-oriented and event-driven programming concepts. However, there is still a lack of a development methodology that systematically supports event-based information system construction. From a business perspective, an information system is one that supports business processes efficiently and effectively to improve business performance. These business processes are composed of business activities which involve a series of business events. A business event is executed according to a business scenario. Therefore, it is necessary to grasp these events in the requirements analysis stage and to apply it on the system development methodology. However, information systems development methodology which systematically reflect the event processing concept still is insufficient. From this viewpoint, this paper proposes an event-driven scenario-based development methodology that can meet the recent development environment of information systems, and applies the proposed methodology to a small scale information system development case.

6시그마 성공요인이 흡수역량과 기업성과에 미치는 영향

장길상,송정수 경성대학교 산업개발연구소 2013 산업혁신연구 Vol.29 No.4

최근 많은 기업들은 경쟁력 향상을 위하여 경영혁신기법으로 꾸준히 6시그마를 추진하고 있다. 이러한 경영환경에서, 본 연구에서는 6시그마 성공요인(최고경영층의 지원, 교육 및 훈련, 성과보상, 고객 및 품질중심의 사고)이 흡수역량과 기업성과에 미치는 영향과 그 과정에서 흡수역량의 매개 작용에 관하여 연구하였다. 연구목적을 달성하기 위하여, 울산시에 소재하고 있는 ‘H’ 기업에 근무하는 종업원 221명의 응답을 표본으로 SPSS 18.0을 이용하여 검증하였다. 연구결과, 최고경영층의 지원을 제외한 나머지 다른 6시그마 성공요인의 모든 하위차원들은 흡수역량에 통계적으로 유의한 정(+)의 영향을 미치고 있는 것으로 나타났으며, 흡수역량은 기업성과에 통계적으로 유의한 정(+)의 영향을 미치고 있는 것으로 나타났다. 또한 최고경영층의 지원을 포함한 6시그마 성공요인의 모든 하위차원들은 기업성과에 통계적으로 유의한 정(+)의 영향을 미치고 있는 것으로 나타났다. 마지막으로, 최고경영층의 지원을 제외한 나머지 다른 6시그마 성공요인의 모든 하위차원들과 기업성과 사이의 관계에 있어서 흡수역량이 부분 매개 작용을 하는 것으로 나타났다. 이러한 결과는 기업의 경쟁력 우위확보를 위한 기업성과를 제고하기 위하여, 6시그마 성공요인의 기반 하에 조직구성원의 흡수역량을 강화해야 함을 시사하고 있다.

웹기반 Generic BOM 관리 시스템의 설계 및 구현

장길상,김재균,이종훈 한국산업경영시스템학회 2000 한국산업경영시스템학회지 Vol.23 No.57

동적 이벤트를 고려한 수주생산환경의 계층적 생산계획 및 통제 시스템

장길상,김재균,Jang, Gil-Sang,Kim, Jae-Gyun 대한산업공학회 2001 산업공학 Vol.14 No.1

Production planning and control system plays an important role in manufacturing companies because it determines all production capacity planning, material procurement planning, and production scheduling which are needed in the process of producing products. Many researches on production planning and control system have been conducted for many manufacturing companies for recent decade. But, a considerable research achievement has mainly been obtained on the forecast-driven production for a make-to-stock and an assemble-to-order. The reason is that there are some hardships such as difficulties of standardizing product information, the frequent changes of design and material, and the unexpected dynamic events that influence the production of customer's order in a make-to-order or an engineering-to-order environments. By these characteristics and their complexities, some studies for production planning and control system in a make-to-order environment are presented recently. In this paper, we present the framework of the hietachical production planning and control for a make-to-order environment with dynamic events. In order to illustrate the usefulness of the proposed framework for a hietachical production planning and control, the information system for a make-to-order production was implemented with the object of the company of producing electricity transformer.

기업용 SNS 활용이 커뮤니케이션과 업무성과에 미치는 영향

장길상 대한안전경영과학회 2018 대한안전경영과학회지 Vol.20 No.2

This study empirically verified the effect of enterprise SNS usage on communication and work performance and the effect of communication on work performance for corporate employees. To accomplish the purpose of this study, we proposed a research model, set up research hypotheses, and verified the hypotheses based on previous studies. For this study, we surveyed the employees of manufacturing companies located at Ulsan city. The results of this study are summarized as follows. First, the use of enterprise SNS has a significant effect on communication. Second, communication has a significant effect on work performance. Third, the use of enterprise SNS has a significant effect on work performance. Through the results of this study, it can be confirmed that the introduction and utilization of enterprise SNS suitable for enterprises leads to the satisfaction of employees' communication and improvement of the work performance.

6시그마 성공요인이 변화관리활동과 경영성과에 미치는 영향

장길상,안완준 대한안전경영과학회 2017 대한안전경영과학회지 Vol.19 No.3

This study is an empirical study on the relationships among success factors of six sigma (support of top management, education and training, performance-based reward, customer and quality focused thought) on change management activity and business performance. In particular, mediating effect of change management activity on the relationship between success factors of six sigma and business performance is empirically analysed to find causes and impacts among these variables. The study results are as follows: First, there were positive relationships between critical success factors of six sigma(except support of top management) and change management activity. Second, there was also a positive relationship between change management activity and business performance. Third, there were also positive relationships between critical success factors of six sigma and business performance. Finally, change management activity was partial mediating effects on the relationship between critical success factors of six sigma(education and training, performance-based reward, customer and quality focused thought) and business performance. On the other hand, support of top management had no mediating effect on business performance.

데이터 마이닝 기반의 6 시그마 방법론 : 철강산업 적용사례

장길상 한국정보시스템학회 2011 情報시스템硏究 Vol.20 No.3

Recently, six sigma has been widely adopted in a variety of industries as a disciplined, data-driven problem solving approach or methodology supported by a handful of powerful statistical tools in order to reduce variation through continuous process improvement. Also, data mining has been widely used to discover unknown knowledge from a large volume of data using various modeling techniques such as neural network, decision tree, regression analysis, etc. This paper proposes a six sigma methodology based on data mining for effectively and efficiently processing massive data in driving six sigma projects. The proposed methodology is applied in the hot stove system which is a major energy-consuming process in a "P" steel company for improvement of heat efficiency through reduction of energy consumption. The results show optimal operation conditions and reduction of the hot stove energy cost by 15%.