• Title/Summary/Keyword: 영역 한정성

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NOx Formation and Emission Characteristics of Premixed Swirl Flame of Natural Gas (천연가스 선회 예혼합 화염의 NOx 생성 및 배출 특성)

  • You, Hyun-Seok;Lee, Joong-Seong;Han, Jeong-Ok
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.23 no.6
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    • pp.788-794
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    • 1999
  • The swirl flame is mostly used to stabilize the flame on the burner nozzle in the industrial combustor. In the case of the weak swirl flame(S<0.4), the recirculation zone could not be formed, but in the strong swirl(S>0.6) flame, it could be formed in the center of the swirl flame. In this study, the measurement and analysis of emission species, temperature, radicals of premixed swirl flame in the combustor were performed to understand the NO formation and emission characteristics of the swirl flame of natural gas. The result of NO emission in the swirl flame is that the amount of NO emission in the strong swirl flame decreased about 60% compared with that of the weak swirl flame. The main region of NO formation of the weak swirl flame is positioned in the down stream(z=100~200mm) of the flame, but that of the strong swirl flame is positioned in the up stream(z=40mm) where the recirculation zone seems to be formed. It is supposed that the increase of flame surface and the formation of inversed flame cause the reduction of the high temperature region on the production of NO in the strong swirl flame. The result of NO-temperature relation revealed that the factor of NO formation is not only temperature but also another parameters in the weak swirl flame, but in the strong swirl flame, NO is proportional to the temperature of higher than 1200K.

A Research on Derivation of Strategic Brain Research Areas by the AHP Approach (AHP를 이용한 뇌융합 전략분야 발굴 연구)

  • Kim, Junhuck;Suh, Dukrok;Choi, Jee Hyun;Kim, Han-Gook
    • The Journal of the Korea Contents Association
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    • v.16 no.4
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    • pp.36-44
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    • 2016
  • This article serves as a guideline to the policy on Korea brain science program. Given limited resources within Korea, setting priorities in brain science topics is important in science policy. In this study, we determined the priorities of important brain science topics based on the frontier properties, innovativeness, and prospective outcome. Firstly, the significant topics were chosen after the interview with the top nationwide brain scientists, which were neuroglia, brain precision medicine, neuromorphic engineering, neuroepigenetics, and brain oscillation. Secondly, the analytic hierarchy process (AHP) survey were conducted to prioritize and assign the important weight for not only the criteria but also the research topics in pair choice evaluation. In regards to the importance among the criteria, prospects of the topic was determined to be the top criterion to ranked criterion to consider in the government investment. The priority of the research topics was determined by the order for the project to be considered in national science policy in a comparative way.

Institutional Improvement for Practical Applications of the Smart Water Grid in South Korea (지능형 물관리(Smart Water Grid)의 제도적 한계와 개선방향)

  • Park, Sung-Je;Ryu, Si-Saeng
    • Proceedings of the Korea Water Resources Association Conference
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    • 2011.05a
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    • pp.110-110
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    • 2011
  • 최근 국제적으로 물관리의 차세대 개념으로서 지능형 물관리(Smart Water Grid)가 활발하게 논의되고 있다. 우리나라에서도 일부 학자들을 중심으로 이에 대한 개념이 도입되고 있다. 현재까지 정리된 지능형 물관리의 개념은 최근 급성장한 정보통신기술을 활용하여 기존에 비효율적으로 운영되는 물관리의 시스템을 획기적으로 개선하자는 것이다. 따라서 이론적으로는 물의 생산, 정수, 배송 그리고 이용과 처리에 이르는 전 과정을 실시간으로 통합하여 관리하는 것이 가능하다. 국제적으로는 IBM과 Siemens 등과 같이 정보통신과 물산업을 선도하는 기업 주도의 기술개발이 진행되는 단계이다. 2000년대 초반에는 용수수급의 효율화를 위한 장치개발에 주력하였으나, 현재에는 용수수급과 관련된 제반사항에 대한 기술적 통합시스템 구축으로 적용범위를 넓히고 있다. 우리나라에서도 도시인프라 자료의 통합관리와 수질 모니터링 시스템 구축이 추진되었으며, 2010년 12월 발표된 새만금종합개발계획에서는 본격적으로 활용을 검토하고 있다. 그러나 지능형 물관리의 기술적 통합시스템 전략은 곧 심각한 제도적 장벽에 직면할 것이다. 아무리 우수한 기술적 시스템이 개발된다고 하여도 제도적 기반의 구축이 없으면 국민경제에 도움이 되는 현실적용에는 한계가 있다. 기존에 확립된 물관리의 제도적 기반으로는 한정된 지역의 좁은 영역에서 활용될 수밖에 없다. 이것은 우리나라의 물관리가 기본적으로 법적, 제도적, 행정적 차원에서 분리되어 운영되고 있기 때문이다. 본 연구는 지능형 물관리가 지향하는 기술적인 통합시스템 구축이 당면할 제도적 한계를 도출하고 이를 극복하기 위한 정책적 방향을 제시하고자 한다. 또한 2009년 국회에 제출된 물관리기본법(안)에 지능형 물관리의 개념을 도입하는 방안을 모색하고자 한다.

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A Technique for Mixed Pixel Extraction by Canonical Vector Analysis (정준벡터분석에 의한 혼합화소 해석기법에 관한 연구)

  • 박민호
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.16 no.1
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    • pp.75-84
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    • 1998
  • To achieve more accurate information from satellite image data, a research on a technique for mixed pixel ex-traction has been produced. The mixed pixels with only two land covers have been experimented. By analyzing canonical vector in canonical correlation classification, the mixed pixels have been classified. The ratio of the two canonical weighted values-the elements of canonical vector have been used as a threshold to discriminate mixed pixels. In case of the classification for the mixed pixels of bridge and water class in TM data before or after the 1st of September, the threshold for the optimal classification of the mixed pixels is 4.0. That is, if the ratio of the two canonical weighted values is less than 4.0, the pixel is a mixed pixel. Also, using the distribution of canonical weighted values, the constitution percentages of land covers within one mixed pixel can be approximately deducted. The accuracy of mixed pixel extraction for experimental area is 90% and quite acceptable. Conclusively, a technique for mixed pixel extraction by canonical vector analysis is effective.

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화학적기상증착법에 의해 성장된 BixTey 계 박막의 미세구조 연구

  • Lee, Yu-Min;Kim, Yeong-Heon;Ryu, Hyeon;Jeon, Gi-Mun;Gang, Sang-U;Kim, Yong-Gyu
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.178-178
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    • 2011
  • 군사용 장비의 전원장치, 인공위성, 해양개발용 등의 특정분야에 한정되어 이루어지던 열전물질에 대한 연구가 최근에는 에너지원의 다양화와 에너지 절약에 대한 필요성이 크게 대두됨에 따라 산업 폐열과 각종 열기관의 폐열 및 해수 온도차나 태양열과 같은 자연에너지를 이용하는 열전발전에 대한 연구로 영역이 확장되어 꾸준히 이루어지고 있다. 다양한 열전 재료 중에서 BixTey 계, BixSey 계, SbxTey 계, 혹은 이들의 합금계가 많이 연구되고 있다. 이 중에서 BixTey 계의 박막 성장 방법으로는 sputtering deposition, electrodeposition, flash evaporation, molecular beam epitaxy, chemical vapor deposition (화학적기상증착) 등이 있다. 이러한 다양한 방법들 중에서 화학적기상증착법은 양질의 두꺼운 막을 성장시킬 수 있음과 동시에 산업적인 생산에 적용될 수 있기 때문에 열전박막 증착을 위한 중요한 수단이 될 수 있을 것으로 생각되고 있다. 하지만 적절한 전구체(precursor)의 부족, tellurium (Te)의 재증발과 같은 문제점 때문에 화학적기상증착법을 이용한 BixTey 계 박막에 대한 전반적인 연구가 부족한 실정이다. 본 연구에서는 다양한 기판, 예를 들면, 실리콘(Si), 실리콘 산화물(SiO2), 백금(Pt) 등, 에 화학적기상증착법을 이용하여 BixTey 계 박막을 성장시키고, 온도와 압력 등의 조건 변화에 따른 박막의 형상과조성, 구조적 특성에 관한 연구를 진행하였다. 특히, 성장 조건에 따른 박막의 형상 연구를 통하여 성장 기구에 관한 고찰을 진행할 수 있었다. 나아가 투과전자현미경 연구를 통하여 기판과 박막의 계면 특성과 개별 결정립이 가지는 미세구조적 특성에 관한 연구를 진행하였다.

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A Network Management Architecture Using XML-based PIB (XML기반 PIB를 이용한 네트워크 관리구조)

  • 윤권섭;홍충선
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.5B
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    • pp.414-426
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    • 2003
  • XML is being used to describe components and applications in a vendor and language neutral. Therefore it already has a role in distributed system. XML is also being used as a data interchange format between components and applications in loosely coupled large-scale application. Until now, policy is described for specific applications and devices. Its use has been very limited. In current network management system, we can only invoke predefined operations and actions using policy-based network management. The main motivation for the recent interests in policy-based networks is to support dynamic adaptability of behavior by changing policy without recoding or stopping system. For these reasons we present the use of the XML for describing the policy and PIB(Policy Information Base) in COPS-PR. It improves flexibility and interoperability among heterogeneous network systems. It also can add new functionality into network components. In this paper, we propose a dynamically extensible network management architecture using XML-based PIB.

A re-route method for reliable data transport in Ad Hoc Networks (Ad Hoc 망에서 신뢰성 있는 데이터 전송을 위한 경로 재설정 기법)

  • 한정안;백종근;김병기
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.3A
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    • pp.276-287
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    • 2004
  • An ad hoc network is infra(Base Sstation or Access Point) free wireless mobile communication technology. Mobile nodes function as routers and servers in ad hoc networks. Many routing protocols for ad hoc network have been proposed. If any route is broken owing to moving node, source must repair broken route again. But route repair technology after route collapses is not suitable to transmit real-time data packet for QoS guarantee. So this paper presents route repair technology that prevents route from breaking. If intermediate node moves to critical section, the node issues handoff packet and sends the packet to the next node. After next node receives handoff packet, the node broadcasts route request packet to the previous node for intermediate node. Finally, even if intermediate node moves out of the routing region, the source can continuously transmit data packets to the destination through the new path.

Political Economy in the Age of Broadcast and Telecommunications Convergence: An Introductory Inquiry for Critical Succession (방송통신 융합 시대의 정치경제학: 비판적 계승을 위한 시론적 탐색)

  • Lee, Nam-Pyo;Kim, Jae-Young
    • Korean journal of communication and information
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    • v.33
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    • pp.193-225
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    • 2006
  • This study attempts to reconsider the significance of political economy as a theory of knowledge and/or a method for explaining the convergence of broadcast and telecommunications. It is going to suggest what the domains of political economy should be in the future by both highlighting the characteristics and blind spots of previous studies and drawing some distinctive features of a new media environment. The principals and recent research trends in political economy are reviewed in order to make clear that the historical totality as a meta-framework of political economy needs to be reexamined in the era of convergence. Although the scope of political economy has been limited to criticize the structure of media ownerships, the study emphasizes the importance of media consumer theory. It also discusses the problems of free market theory, distortion of active media audience theory, and limitations and creative tension of audience commodity. Finally, this study stresses the significance of audience-oriented policies in order to make approach to practical sides of media politics.

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Design of Image Tracking System Using Location Determination Technology (위치 측위 기술을 이용한 영상 추적 시스템 설계)

  • Kim, Bong-Hyun
    • Journal of Digital Convergence
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    • v.14 no.11
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    • pp.143-148
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    • 2016
  • There is increasing concern about security as a need for increased safety in the information industry society. However, it does not meet the needs for safety including CCTV. Therefore, in this paper, we link the processing technology using the image information to the IPS system consisting of GPS and Beacon. It designed a conventional RFID tag attached discomfort and image tracking system is limited to complement the disadvantages identifiable area. To this end, we designed a smart device and the Internet of Things convergence system and a research to ensure the accuracy and reliability of the IPS of the access control system. Finally, by leveraging intelligent video information using a PTZ camera, and set the entrant management policies it was carried out to control the situation and control. Also, by designing the integrated video tracking system, an authentication server, visualization systems were designed to establish an efficient technique for analyzing the IPS entrant behavior patterns.

Range Query Processing using Space and Time Filtering in Fixed Grid Indexing (고정 그리드 인덱싱에서 공간과 시간 필터링을 이용한 범위 질의 처리)

  • Jeon, Se-Gil;Nah, Yun-Mook
    • The KIPS Transactions:PartD
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    • v.11D no.4
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    • pp.835-844
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    • 2004
  • Recently, the location-based service for moving customers is becoming one of the most important service in mobile communication area. For moving object applications, there are lots of update operations and such update loads are concentrated on some particular area unevenly. Range queries, whose range can be window or circular, are the most essential query types in LBS. We need to distinguish completely contained cells from partially contained cells in those range queries. Also, it is necessary to consider temporal dimension to filter out qualifying objects correctly. In this paper, we adopt two-level index structures with fixed grid file structures in the second level, which are designed to minimize update operations. We propose a spatial ceil filtering method using VP filtering and a combined spatio-temporal filtering method using time gone concepts. Some experimental results are shown for various window queries and circular queries with different filtering combinations to show the performance tradeoffs of the proposed methods.