• Title/Summary/Keyword: 집적요인

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국지풍이 소규모만의 해수유동에 미치는 영향

  • 이충일;김동선;조규대
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.05a
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    • pp.244-245
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    • 2001
  • 육상 환경과 인접해 있는 연안해양환경은, 그 변화 특성이 매우 독특하며 복잡하게 나타난다. 해양환경 변화에 큰 영향을 미치는 것 중에는 해류와 조류 등과 같은 유체의 운동의 역할이 크다. 특히 바람과 같은 기상환경인자는 해표면의 유체의 운동에 큰 영향을 주게 되며, 이로 인하여 유체내의 입자물질(적조생물, 유류 등)의 집적 및 확산에 결정적인 영향을 끼치게 된다. 우리 나라는 계절풍이 뚜렷하게 나타나는 지역이지만, 지역에 따라서는 주변 지역과의 기압배치 및 지형적인 요인등에 의해서 그 특성이 충분히 변할 수 있다. 이러한 지역적인 국지풍은 만과 같은 소규모 지역에서 큰 영향을 끼칠 것으로 생각된다. (중략)

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High-efficiency coupling technique for photonic crystal waveguides using a waveguide lens (도파로 렌즈를 이용한 광결정 도파로의 광결합 효율성 개선)

  • 채우림;김현준;이승걸;오범환;박세근;이일항
    • Proceedings of the Optical Society of Korea Conference
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    • 2003.07a
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    • pp.212-213
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    • 2003
  • 집적 광학(Integrated Optics) 소자에서 기존 광도파로와 광결정 도파로 간의 효율적 결합 및 접속의 안정성은 매우 중요한 과제이다. 기존의 단일모드 광도파로의 폭은 수 $mu extrm{m}$ 정도임에 비하여, 광 결정을 이용한 단일 결함 도파로인 경우 그 폭은 보통 1$\mu\textrm{m}$ 이하이다. 또한 광결정 도파로의 광 가둠 효과가 우수하여 기존 도파로와의 결합 사이에 모드 부정합 현상이 발생하며, 이것은 광결정 도파로의 광결합 효율은 낮게 하는 요인이 된다. (중략)

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The Distribution Structure of the Internet Movie and Spatial Clustering of the Internet Movie Industry (인터넷 영화의 유통구조와 인터넷 영화산업의 공간적 집적화)

  • Lee, Hee-Yeon;Lee, Nan-Kyung
    • Journal of the Economic Geographical Society of Korea
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    • v.8 no.1
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    • pp.107-130
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    • 2005
  • The purpose of this study were to examine the spatial distribution and locational characteristics of the Internet movie industry, to seize the value chains of the Internet movie industry and distribution structure of the internet movies, and to analyze the vertical-horizontal linkages of the Internet movie firms and their spatial clustering. Recently, the Internet movie industry has developed rapidly due to the development of techniques related to movie contents, the broadband Internet and a wide expansion of the high speed communication network and the increase of demands on movie contents. It has been found that 74$\%$ of the Internet movie industry was concentrated in Seoul. Especially this industry was quite agglomerated in several dongs of Gangnam-gu such as Yoeksam, Nonhyeon, Daechi and Samseung. The proximity of the same or similar business firms was the primary locational factors that influenced on the Internet movie industry, followed by other factors such as convenience of transportation, the reputation of the place, and proximity of technically supporting firms. The Internet movie industry had the valve chain composed of 'contents suppliers $\rightarrow$ contents distributors $\rightarrow$ service providers', However, there were also a complex network of the VOD copyright owner, VOD syndicator, and service providers in each category of the value chain. This research clearly revealed that the localized clustering has been formed with the movie contents providers, technically supporting firms, client firms, and cooperative-affiliated business firms related to the Internet movie industry, Additionally, a very intimate network has been established within the clustering, inducing the enlargement of the market and decrease of costs, the co-sharing of tacit knowledge, and the synergy effect.

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Flood Damage Estimation causing Backwater due to the Blockage by Debris in the Bridges (교량에 집적된 유송잡물의 배수영향에 의한 홍수피해 분석)

  • Kim, Soo-Jun;Chung, Jae-Hak;Lee, Jong-Seol;Kim, Ji-Tae
    • Journal of the Korean Society of Hazard Mitigation
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    • v.7 no.4
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    • pp.59-66
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    • 2007
  • The bridge crossing river is the one of the major factors causing backwater level rising. Furthermore, the bridges in the mountainous areas increase the flood damage in the upstream of the bridge due to the blockage by debris. In this research, the effects of debris to the magnitude of flood damage in the study river basin were simulated by using HEC-RAS and HEC-GeoRAS models. With assumption that the backwater caused by debris blocking the space between bridge piers is the only factor causing inundation, the unsteady flow simulation was carried out with various case studies. The potential inundation area with the overflow locations and volumes could be estimated as the results of simulation. However, the simulation results also reveal the limitations of inaccurate estimation of inundation area and depth. To overcome these hindrances, DEM and satellite images were applied to the simulation. By readjusting the inundation area using digital maps and satellite images and calibrating overflow volume and depth using DEM, the accuracy of simulation could be increased resulting more accurate flood damage estimation.

A Case Study on the Development of an ICT Convergence Innovation Cluster for Creative Economy (창조경제를 위한 ICT 융합 혁신 클러스터 구축 사례 연구)

  • Im, Jongbin;Kim, Yeseul;Chung, Sunyang
    • Journal of Korea Technology Innovation Society
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    • v.17 no.1
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    • pp.1-24
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    • 2014
  • The new Korean government sets its main policy direction as Creative Economy. The Creative Economy can be defined as a growth strategy that establishes new companies, enhances the competitiveness of established companies and creates new markets, industries and jobs in consequence of combining of creative imagination, science and technology and ICT. In this context, the concept of innovation cluster, which aims to foster technological innovations from an organic ecosystem perspective, can be a valid policy instrument for attaining Creative Economy. Innovation cluster can and must make a contribution to achieving the Creative Economy of Korea. In particular, the ICT Convergence Innovation Cluster will be a good strategy for this purpose. Based on this conceptual background, this paper analyzes a recently notable case of an ICT Convergence Cluster in Korea, Pangyo Technovalley (PTV). We argue that the Pangyo Technovalley is a representative cluster of converging ICT and science and technology. We identify the major factors for successful development of ICT cluster: regional government's flexible response to environmental change, careful pre-planning and balance between private and public involvement. In addition, we also found that additional factors, settlement condition for securing good workforce, agglomeration of various innovation actors for promoting convergence, and cluster network revitalization are also important for implementing the creative ICT convergence cluster.

Teaching Location Using Newpaper Articles: Venture Firms as an Example (신문기사를 활용한 입지론 수업 : 벤처기업의 입지 사례)

  • Kwon, Sang-Cheol
    • Journal of the Economic Geographical Society of Korea
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    • v.11 no.1
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    • pp.78-93
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    • 2008
  • Location is the key theme in geography and various location theories are well established for diverse economic activities. As normative theory, the logical presentation of the location theories tends to make students appraise the class difficult and lose interests. This study presents a teaching materials and inductive method for the location of venture firms using newspaper articles as an example of the knowledge and information industry. Presented are various newspaper articles about venture firms in which the locational notions are selected to find out general location factors. And then their locational preference of large cities, diseconomies of agglomeration, the possibilities of deconcentration from large cities and new establishments in peripheral regions are presented in order. The inductive way of teaching location from specific examples to general tendencies using NIE could bring students' interests and participation which is in line with the student-oriented inquiry-based teaching emphasized recently in educational methods. It could be an effective teaching method for the location theories in economic geography and other difficult subjects.

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Location and Spatial Variations of Ceramic Industry in Miryang City, Kyongnam Province, Korea (밀양시 요업의 입지와 공간변화)

  • Lim, Yeong-Dae
    • Journal of the Korean association of regional geographers
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    • v.8 no.1
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    • pp.40-64
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    • 2002
  • The locational characteristics of ceramic industry in Miryang city, Kyongnam province, were clarified by means of examining the process of its formation, spatial variation, locations and their changes. The government policy on industry and the business fluctuation are important in the quantitative changes of the industry. The spatial variation of industry toward the outer part of area are the results of equilibrium between the decrease of firms in inner city and the increase of firms in outer part. The births and deaths of firms played important role in the processes of spatial variations. The industry location has lasted by the accumulation of location decision of 'potential entrepreneurs' who learned knowledges on the industry and had personal contacts with the business-related persons for long time. The main factors on the locational decision of firms are personal factor, raw materials, land, water and market. The locational problems have mainly related with plant expansion, land, marketing, labour and capital. They caused investment changes and caused relocations of firms. Such disadvantages as raw material exhaustion, shortage of land and congestion within the agglomeration area, development of road transportation and local government policy on industry location, induced recent decentralization of industry to outer part.

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A Block Disassembly Technique using Vectorized Edges for Synthesizing Mask Layouts (마스크 레이아웃 합성을 위한 벡터화한 변을 사용한 블록 분할 기법)

  • Son, Yeong-Chan;Ju, Ri-A;Yu, Sang-Dae
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.38 no.12
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    • pp.75-84
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    • 2001
  • Due to the high density of integration in current integrated circuit layouts, circuit elements must be designed to minimize the effect of parasitic elements and thereby minimize the factors which can degrade circuit performance. Thus, before making a chip, circuit designers should check whether the extracted netlist is correct, and verify from a simulation whether the circuit performance satisfies the design specifications. In this paper, we propose a new block disassembly technique which can extract the geometric parameters of stacked MOSFETs and the distributed RCs of layout blocks. After applying this to the layout of a folded-cascode CMOS operational amplifier, we verified the connectivity and the effect of the components by simulating the extracted netlist with HSPICE.

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Design of Charge Pump Circuit for Floating Gate Power Supply of Intelligent Power Module (Intelligent Power Module의 플로팅 게이트 전원 공급을 위한 전하 펌프 회로의 설계)

  • Lim, Jeong-Gyu;Chung, Se-Kyo
    • The Transactions of the Korean Institute of Power Electronics
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    • v.13 no.2
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    • pp.135-144
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    • 2008
  • A bootstrap circuit is widely used for the floating gate power supply of Intelligent power module (IPM). A bootstrap circuit is simple and inexpensive. However, the duty cycle and on-time are limited by the requirement to refresh the charge in the bootstrap capacitor. And the value of the bootstrap capacitor should be increased as the switching frequency decreases. A charge pump circuit can be used to overcome the problems. This paper deals with an analysis and design of a charge pump circuit for the floating gate power supply of an IPM. The simulation and experiment are carried out for an induction motor drive system. The results well verifies the validity of the proposed circuit and design method.

Investigation of Junctionless Transistors for High Reliability

  • Jeong, Seung-Min;O, Jin-Yong;Islam, M. Saif;Jo, Won-Ju
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.142-142
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    • 2012
  • 최근 반도체 산업의 발전과 동시에 소자의 집적화에 따른 단채널 효과가 문제되고 있다. 채널 영역에 대한 게이트 영역의 제어능력이 떨어지면서 누설전류의 증가, 문턱전압의 변화가 발생하며, 이를 개선하기 위해 이중게이트 혹은 다중게이트 구조의 트랜지스터가 제안되었다. 하지만 채널길이가 수십나노미터 영역으로 줄어듦에 따라 소스/드레인과 채널간의 접합형성이 어렵고, 고온에서 열처리 과정을 거칠 경우 채널의 유효길이를 제어하기 힘들어진다. 최근에 제안된 Junctionless 트랜지스터의 경우, 소스/드레인과 채널간의 접합이 없기 때문에 접합형성 시 발생하는 공정상의 문제뿐만 아니라 누설전류영역을 개선하며, 기존의 CMOS 공정과 호환되는 이점이 있다. 한편, 집적화되는 반도체 기술에 따라, 동작 시 발생하는 스트레스가 소자의 신뢰성에 중요한 요인으로 작용하게 되며, 현재 Junctionless 트랜지스터의 신뢰성 특성에 관한 연구가 부족한 상황이다. 따라서, 본 연구에서는 Junctionless 트랜지스터의 NBTI 특성과 hot carrier effect에 의한 신뢰성 특성을 분석하였다. Junctionless 트랜지스터의 경우, 축적모드로 동작하기 때문에 스트레스에 의해 유기되는 캐리어의 에너지가 낮다. 그 결과, 반전모드로 동작하는 Junction type의 트랜지스터에 비해 스트레스에 의한 subthreshold swing 기울기의 열화와 문턱전압의 이동이 감소하였다. 또한 소스/드레인과 채널간의 접합이 없기 때문에 hot carrier effect에 의한 게이트 절연막 및 계면에서의 열화가 개선되었다.

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