• 한국연소학회:학술대회논문집
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• 한국연소학회 2006년도 제32회 KOSCO SYMPOSIUM 논문집
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• pp.149-156
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• 2006

Structure of edge flame established in a mixing layer, formed between two uniformly flowing pure $CH_4$ and pure $O_2$ streams, is numerically investigated by employing a detailed methane-oxidation mechanism. The numerical results exhibited the most outstanding distinction of using pure oxygen in the fuel-rich premixed-flame front, through which the carbon-containing compound is found to leak mainly in the form of CO instead of HC compounds, contrary to the rich $CH_4-air$ premixed flames in which $CH_4$ as well as $C_2H_m$ leakage can occur. Moreover, while passing through the rich premixed flame, a major route for CO production, in addition to the direct $CH_4$ decomposition, is found to be $C_2H_m$ compound formation followed by their decomposition into CO. Beyond the rich premixed flame front, CO is further oxidized into $CO_2$ in a broad diffusion-flame-like reaction zone located around moderately fuel-rich side of the stoichiometric mixture by the OH radical from the fuel-lean premixed-flame front. Since the secondary CO production through $C_2H_m$ decomposition has a relatively strong reaction intensity, an additional heat-release branch appears and the resulting heat-release profile can no longer be seen as a tribrachial structure.

• 한국연소학회지
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• 제11권1호
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• pp.19-26
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• 2006

Structure of edge flame established in a mixing layer, formed between two uniformly flowing pure $CH_4$ and pure $O_2$ streams, is numerically investigated by employing a detailed methane-oxidation mechanism. The numerical results exhibited the most outstanding distinction of using pure oxygen in the fuel-rich premixed-flame front, through which the carbon-containing compound is found to leak mainly in the form of CO instead of HC compounds, contrary to the rich $CH_4-air$ premixed flames in which $CH_4$ as well as $C_2H_m$ leakage can occur. Moreover, while passing through the rich premixed flame, a major route for CO production, in addition to the direct $CH_4$ decomposition, is found to be $C_2H_m$ compound formation followed by their decomposition into CO. Beyond the rich premixed flame front, CO is further oxidized into $CO_2$ in a broad diffusion-flame-like reaction zone located around moderately fuel-rich side of the stoichiometric mixture by the OH radical from the fuel-lean premixed-flame front. Since the secondary CO production through $C_2H_m$ decomposition has a relatively strong reaction intensity, an additional heat-release branch appears and the resulting heat-release profile can no longer be seen as a tribrachial structure.

• 한국정보통신학회논문지
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• 제15권2호
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• pp.382-388
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• 2011

본 논문에서는 프로로밍 에이전트의 데이터의 안전한 수행을 위해 악의적인 요인들에 의해 발생될 수 있는 절단공격으로부터 안전한 실행을 보장한다. 또한 기존의 체인관계보다 확장성을 개선한 쿼리 트리체인 관계(QCRT:query chain relationship tree)구조를 형성함으로써 악의적인 요소를 효과적으로 검출 할 수 있다. 또한 체인 관계 구조를 에이전트의 여정에 따라 형성되는 구조로 체크함으로써 에이전트의 체인관계를 확장하였다. 단면적인 체인관계의 확장으로 기존의 취약한 요소들을 보완하여 이동 에이전트의 절단공격으로부터 실행 보장을 하였다.

• 대한전기학회논문지:시스템및제어부문D
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• 제49권7호
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• pp.378-388
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• 2000

In this paper, we propose Fuzzy Polynomial Neural Networks(FPNN) based on Polynomial Neural Networks(PNN) and Fuzzy Neural Networks(FNN) for model identification of complex and nonlinear systems. The proposed FPNN is generated from the mutually combined structure of both FNN and PNN. The one and the other are considered as the premise part and consequence part of FPNN structure respectively. As the consequence part of FPNN, PNN is based on Group Method of Data Handling(GMDH) method and its structure is similar to Neural Networks. But the structure of PNN is not fixed like in conventional Neural Networks and self-organizing networks that can be generated. FPNN is available effectively for multi-input variables and high-order polynomial according to the combination of FNN with PNN. Accordingly it is possible to consider the nonlinearity characteristics of process and to get better output performance with superb predictive ability. As the premise part of FPNN, FNN uses both the simplified fuzzy inference as fuzzy inference method and error back-propagation algorithm as learning rule. The parameters such as parameters of membership functions, learning rates and momentum coefficients are adjusted using genetic algorithms. And we use two kinds of FNN structure according to the division method of fuzzy space of input variables. One is basic FNN structure and uses fuzzy input space divided by each separated input variable, the other is modified FNN structure and uses fuzzy input space divided by mutually combined input variables. In order to evaluate the performance of proposed models, we use the nonlinear function and traffic route choice process. The results show that the proposed FPNN can produce the model with higher accuracy and more robustness than any other method presented previously. And also performance index related to the approximation and prediction capabilities of model is evaluated and discussed.

• 한국식생활문화학회지
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• 제13권1호
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• pp.37-46
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• 1998

Distribution structure is the link between a society's needs and its industrial responses. A change in distribution structure brings about a consumption structure which may results in considerable changes in lifestyle including food habits. The purpose of this study was to evaluate a effect of change of distribution structure on the food purchase. The survey was carried from May to June, 1997 by way of questionnaire of 407 housewives, aged 23-64 years, in Seoul and the capital area. The questionaire consists of sociodemographic characteristics of the subjects and distribution channel, information route of food selection, acknowledgement and coefficient of utilization of new distribution channel, mainly used distribution channel in food purchase, important factors in food selection, and food purchasing behavior. Their data were statistically analyzed based on frequency, mean, and $X^2-test$. The major findings of this study were as follows; 1) Most frequently used distribution channels in food purchase were supermarket(38.53%), department store(15.23%), discount store(14.05%), a conventional retail market(13.87%), membership wholesale club(8.07%), and a conventional wholesale market(6.53%). 2) The new distribution channels that subjects have ever used were discount store(75.4% of the subject), membership wholesale club(63%), mail order house(32%), outlet store(29.4%), home shopping(10.3%). 3) Compared to the subject living far from the new distribution channel, the subject living close to the new distribution channel was higher in frequency of new distribution channel utilization. These observations suggest that change of the distribution structure promotes the change of the food purchasing behavior.

• 한국컴퓨터정보학회논문지
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• 제18권10호
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• pp.47-54
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• 2013

본 논문에서는 광인터넷의 구조 설계에 대한 분석과 광서비스망에서 UNI(User Network Interface) 시그널링 프로토콜을 이용한 광전송 실험을 시행하였다. 광인터넷의 계층에 따른백본망, 서비스망, 액세스망에 대한 세부적인 구조를 보여주었고, 각 계층에서 필요한 기능들에 대하여 기술하였다. 이어서 광전달 계층의 제어 구조, 운용관리망 구조, 망간 연동 기술 그리고 라우팅 및 신호망에 대한 기능적 요구조건들을 제시하였다. 이러한 광인터넷망에서 OIF(Optical Internetworking Forum)에 의해서 규정된 UNI 시그널링 프로토콜을 사용하여 전송 실험을 하였다. LSP(Label Switched Path)에 트래픽을 전송하여 설정된 경로를 따라서 메시지가 UNI에 전달되었고, 스위칭을 통하여 최종 목적지에 도착한 TCP(Transmission Control Protocol) 패킷(packet) 값을 보여줌으로서 실시한 광전송이 성공적으로 완료되었음을 확인하였다.

• 지질공학
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• 제18권4호
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• pp.501-509
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• 2008

정성적인 지질정보들의 연계 해석을 위해서는 자료들의 중요도에 따라 정량화가 선행되어야 한다. 이 연구에서는 계층분석과정을 사용하여 정성적 자료를 정량화하였다. 토목, 교통 및 지질관련 전문가 집단(30명)을 구성하여 선형토목구조물 설계에 필요한 지질 및 수리지질에 대한 조사항목을 설문하고 분석하였으며, 이에 따라 조사항목들에 대한 계층구조를 4단계로 구성하였다. 각 단계별 요소에서 선형토목구조물의 안정성에 가장 중요한 요인으로 작용하는 요소는 단층 구조이며, 그 중요도가 46%(0.456)로 나타났다. 단층구조 다음으로는 엽리/층리(0.165), 선구조선(0.144), 지하수(0.124), 암상(0.111) 등의 순으로 중요도를 갖는다.

• 대한토목학회논문집
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• 제37권5호
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• pp.915-926
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• 2017

지하철은 수도권 및 주요 광역지자체에서 버스와 함께 대표적으로 수도권 시민이 가장 많이 이용하는 교통수단이이나 관련 연구 결과를 살펴보면 안내표지에 대한 만족도는 낮고, 안내표지 개선이 필요한 것으로 나타났다. 본 연구에서는 길찾기에 영향을 주는 안내표지를 대상으로 L자형 역사구조를 가진 시청역과 교대역의 안내표지 설치위치, 설치간격, 설치높이, 설치형식 및 실제 이용자를 대상으로 추적 조사, 설문조사를 수행하였다. 그 결과 시청역 및 교대역 모두 L자형의 역사 구조로 인해 이동거리가 길어 원하는 목적지로 정확하게 이동하고 있는지에 대한 확인을 필요로 하였으며, 두 역 모두 안내표지 설치개수(안내표지 과다 부착, 과소 부착), 안내표지 설치 위치(타 시설물에 가려 잘 안보임, 필요 없는 안내표지 설치), 안내표지 설치 높이(너무 낮거나 높게 설치), 기타(작은 안내표지 글씨 크기, 안내표지 내 너무 많은 정보량 존재) 등의 문제를 갖고 있었다. 이는 공간별 정보의 위계에 대한 고려 없이 모든 정보를 제공함으로써 나타난 결과로 본 연구에서는 지하철 역 내 이동(나가기, 타기, 갈아타기) 공간별/그에 따른 행위를 구분하여 L자형 역사 구조일 경우 공간별 안내표지 설치 유형을 정의하였으며, 이동경로 방향유도에 대한 구체적인 원칙을 제안하였다. 해당 연구는 향후 지하철 역 안내표지 유형 및 배치에 중요한 기초자료로 활용 가능할 것으로 판단된다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.303-308
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• 2004

The failure at the head section of rubble mound breakwaters is more important than other failure modes. because this initial failures will occur the failure of the trunk section and lead to the instability of the structure. The three-dimensional failure modes are discussed using the experimental data with multi-directional waves considering the failure modes. It was occurred by the topographical characteristics around the head of rubble mound breakwater. The spacial characteristics of failure mode around the rubble-mound structures can be summarized as follows: 1) It was clarified that the failure modes at the round head of a detached breakwater are classified as failure by plunging breaker on the slope, failure by direct incident wave force and failure at the rubble mound breakwaters. 2) The failure mode was found in the lower wave height than the design wave by the breaker depth effects and topography around structures. It is clarified that the structure was monitored safely designed for the design wave but the failure was occurred by the reason of breaker waves.

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2489-2493
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• 2012

A new fluorescent system (acridine/RTIL hybrid gel) confined in the 3D micro-structure of a poly(lactic acid) membrane were prepared from 1-butyl-3-methylimidazolium-based ionic liquids ([bmim]X (X = $SbF_6$, $NTf_2$, Cl); RTILs), poly(lactic acid) (PLA), and acridine via the sol-gel route. SEM images showed that, in the presence of [bmim]$SbF_6$ and [bmim]$NTf_2$, 3D-ly paticulated structures were created inside the PLA membranes and acridine/RTIL hybrid gels were confined in gabs of particulates. However, the use of [bmim]Cl induced the formation of a 3D-ly porous structure containing the hybrid gel of acridine/[bmimCl in the micropores. The three fluorescent systems exhibited different fluorescence behaviors (fluorescence maximum and intensity) depending on the C2-H acidity scale of the RTILs (or their anion type). Acridine gels hybridized with [bmim]$SbF_6$ and [bmim]$NTf_2$ showed blue fluorescence with relative high intensity, whereas the hybrid gel with [bmim]Cl exhibited almost no fluorescence under dry conditions. However, the acridine/[bmim]Cl hybrid system in the micro-porous PLA membrane started to emit fluorescent light under humid conditions and showed a possible response, indicating that it could be applied as a humidity sensor.