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Low-Intensity Pulsed Ultrasound Promotes Healing with Increases Collagen Deposition and Collagen mRNA Expression in Skin Wound of Rat (저강도 맥동초음파에의한 피부 상처 치유 촉진과 아교질 축적 및 아교질 mRNA 발현 증가)

  • Lee, Jae-Hyoung;Jeka, Seung-Joo;Kwon, Pil-Seung
    • Journal of the Korean Society of Physical Medicine
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    • v.8 no.3
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    • pp.449-456
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    • 2013
  • 목적: 본 연구는 저강도 맥동 초음파적용이 흰쥐의 전층 상처 치유와 아교질 축적 및 아교질 mRNA발현에 미치는 영향을 규명할 목적으로 시행하였다. 방법: 12마리의 Sprague-Dawley계 흰쥐를 저강도 맥동 초음파군(n=6)과 대조군(n=6)에 무작위 배정하고 등에 $19.63mm^2$ 크기의 전층 적출 상처를 만든 다음 저강도 맥동 초음파군은 3 MHz, 순환주기 20%, SATA 강도 $0.4W/cm^2$로 1일 1회, 1회 5분씩 초음파를 적용하고, 대조군은 가짜 초음파를 적용하였다. 7일간 처치 후 초음파군과 대조군의 아교질 축적, 아교질 mRNA 발현, 상처치유율, 절반치유시간을 비교하였다. 결과: 초음파군의 아교질 축적(p<05)과 아교질 mRNA 발현(p<.01)이 대조군보다 유의하게 증가하였고, 상처치유율(p<.05)과 절반치유시간(p<.0)도 초음파군의 대조군보다 유의하게 빨랐다. 결론: 본 연구에서 전층 상처에 저강도 맥동 초음파를 적용한 결과 상처 치유가 촉진되었고 육아조직에 아교질 축적이 증가하였다. 이러한 결과는 맥동 초음파의 기계적 자극이 제 1형 아교질 mRNA 전사활동을 촉진시키는 것으로 사료된다.

Imperfection Mode of Thin Metallic Sandwich Plate with Pyramidal Metallic Inner Structures (피라미드형 금속 내부구조체를 가진 얇은 금속샌드위치 판재의 결함 모드)

  • Ahn, Dong-Gyu;Sun, Hyang-Sun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.37 no.2
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    • pp.187-192
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    • 2013
  • Thin metallic sandwich plate with pyramidal metallic inner structures is manufactured from a continuous projection welding between face sheets and inner structures. Due to the welding pressure, imperfections of inner structures induced by the deformation of the inner structures occur. The imperfections affect the response of the thin metallic sandwich plate subjected to low-velocity impact loading. The goal of this paper is to obtain a proper dominant imperfection mode of the thin metallic sandwich plate with pyramidal metallic inner structures. The variation of impact responses of the thin metallic sandwich plate for different imperfection modes are investigated by finite element analysis. The results of the FE analysis are compared to those of drop impact experiments. From the results of the comparison, it has been shown that the dominant imperfection mode of the thin metallic sandwich plate with pyramidal metallic inner structures is all type of symmetric imperfection mode with symmetrical imperfections of four struts.

Aerodynamic Forces Acting on Yi Sun-sin Bridge Girder According to Reynolds Numbers (레이놀즈수에 따른 이순신대교 거더에 작용하는 공기력의 변화)

  • Lee, Seung Ho;Yoon, Ja Geol;Kwon, Soon Duck
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.1
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    • pp.93-100
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    • 2013
  • The objective of present study is to investigate the sensitivity of aerostatic force coefficients of twin box girder of Yi Sun-sin Bridge according to the Reynolds numbers. This paper presents the 1:30 scale sectional model tests conducted at high speed wind tunnel in Korea Air Force Academy. Comparison with results at low Reynolds number obtained in KOCED Wind Tunnel Center in Chonbuk National University is also provide. The Reynolds number dependency of aerodynamic force coefficients were observed at present streamlined twin box girder. The drag coefficient revealed significant decrease of nearby 23% at supercritical region. The boundary layer trip strip was found to reduce the Reynolds number dependency of aerodynamic forces by fixing the location of flow transition.

A Design and Implementation of a Context-Aware Framework for Mobile Navigation Services (모바일 항법 서비스를 위한 상황인지형 프레임워크의 설계 및 구현)

  • Kim, Hyun-Duk;Choi, Won-Ik;Kim, Jin-Su;Chae, Jin-Seok
    • Journal of Korea Multimedia Society
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    • v.11 no.2
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    • pp.214-227
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    • 2008
  • As cellular network technologies continue to evolve, various network standards coexist in most CDMA-based cellular networks. This means that mobile device users access mobile services over different network bandwidths according to the users' positions or the mobile devices' network access capabilities. Such differences of network bandwidths cause big differences in service response times. To address this problem, we present a framework called CANS (Context-Aware framework for mobile Navigation Services), which takes into account the user's network profile to adapt the contents for CDRG(Centrally Determined Route Guidance) navigation services for cellular phones. To the best of the authors' knowledge, CANS is the first context-aware framework to make mobile navigation services more feasible. The experimental results under commercial CDMA network show that CANS is able to provide similar service response times regardless of type of wireless network to which users connect by adapting the contents to network bandwidths.

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A Preliminary Study on The Delimitation Standard of Maritime Boundary in Korea (우리나라 해상경계 획정기준에 관한 기초 연구)

  • Choi, Yun-Soo;Kim, Jae-Myeong;Kim, Hyun-Soo;Park, Byung-Moon
    • Spatial Information Research
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    • v.20 no.2
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    • pp.45-57
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    • 2012
  • Recently, local governments in Korea are promoting the rapid development of marine for delineating jurisdictional sea area. The importance of a maritime boundary has being emphasized, as jurisdictional sea area disputes among local governments have been increasing. The absence of the delineating standard of maritime boundary has become a source of contention between neighborhood local governments. So the delineating standard of maritime boundary in Korea will be required. The purpose of this study is to derive an improvement plan for the scientific delimitation standard of maritime boundary by analyzing "A hydrographic survey guideline for confirmation of maritime boundary". The results of this study are as follows. Firstly, we defined the concept of the delimitation standard of maritime boundary. Secondly, we set the boundary, factors and processes of the delineating standard of maritime boundary through classifying them in detail. Lastly, we suggested the makeup of a conflict adjustment committee for preventing jurisdictional sea area disputes among local governments.

A study on context of children's library considering user behavior (아동의 독서 및 놀이 행태를 반영한 어린이 도서관 CONTEXT 분석 (아동의 가구 사용방법(Way of Seat)과 아동-부모의 상호작용방법을 중심으로))

  • Song, So-Ra;Pan, Young-Hwan;Jeong, Ji-Hong
    • 한국HCI학회:학술대회논문집
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    • 2009.02a
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    • pp.901-906
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    • 2009
  • 어린이 도서관은 일상생활 가까이에서 지역주민에게 지식정보 서비스를 제공할 뿐 아니라 공공도서관과의 연계를 통해 우리나라 전체 도서관 서비스의 수준을 발전시키고자 하는 생활 친화적 문화기반 시설인 소규모 도서관(혹은 문고)시설이다. 즉 어린이 도서관은 접근성을 가장 큰 장점으로 하여 누구나 쉽고 편리하게 이용할 수 있는 고객중심의 공공도서관 서비스라고 할 수 있다. 어린이 도서관의 주 이용고객은 어린이와 주부로서 최근 이들이 함께 도서관을 이용하는 빈도가 증가하면서 어린이 도서관은 단순히 책을 빌리고 공부를 하는 장소에서 나아가 가족단위의 여가활동이 가능한 문화적 공간으로 변모하여가고 있다. 어린이 도서관은 기본적으로 책을 읽는 조용한 공간이지만 주 이용자가 6세 미만의 유아와 초등학교 저학년 어린이이기에 독서행위와 더불어 또래 친구들과의 친교행위. 부모님과의 정서적 유대감 형성행위, 소규모 근육활동과 같은 놀이행위가 병행된다. 또 어린이 도서관에서 사용되어지는 정형적인 모듈의 서가를 비롯한 입식. 좌식 테이블과 의자들은 소수의 디자이너에 의해 만들어진 것이지만 그것을 이용하는 다수의 어린이들은 디자이너의 의도와 방법에 따라 가구를 사용하는 것 외에도 환경적 컨텍스트에 맞추어 가구의 새로운 쓰임을 발견하며 훨씬 더 다채로운 방법으로 가구를 사용하고 있다. 따라서 본 연구의 목적은 독서 및 놀이 행위 시 아동-부모의 상호작용 방법에 기반하여 아동의 가구사용방법(Way of Seat)을 알아보고 이를 바탕으로 어린이의 행태정보를 모델링하여 가구를 사용하는 어린이의 다양한 행위 이면에 내재된 요구를 파악하는데 있다. 가구를 사용하는 어린이의 다양한 행태 이면에 내재한 어린이만의 특성과 요구를 알아보기 위해서는 먼저 어린이 도서관이라는 특수한 물리적 환경요인 및 사용자 컨텍스트(Context)에 대한 이해가 선행되어야 한다. 이를 위해 기반조사 및 어린이 도서관 방문을 통한 정황조사(Contextual Inquiry)를 실시하였다. 이를 통해 6세 미만의 유아와 초등학생의 가구사용방법(Way of Seat)과 독서 및 놀이 행위 시 행태를 관찰하여 Photo Based Research를 바탕으로 어린이의 행태정보를 모델링 하였다.

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Evaluation the Impact of Installing a Isolation Valve on Condensate System of Nuclear Power Plan (원자력발전소 복수기 수실 차단밸브 설치 영향 평가)

  • Lee, Sun-Ki
    • Journal of Industrial Convergence
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    • v.18 no.4
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    • pp.15-21
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    • 2020
  • Because there are no isolation valves in condensate system of nuclear power plants, circulating water pump was shutdown for the condenser repair. When circulating water pump was shutdown, power plant output decreased about 45%. These output decreasing can minimize by establishing isolation valves. In this paper, evaluated effect to flow conditions change of condensate system, structural integrity of system, condenser pressure of in case of establish isolation valves to condensate system. Results of the evaluation, the flow rate due to the installation of the isolation valve decreased 0.3% when the valve was fully opened and 4.5% when fully closed. In addition, it was found that the vacuum degree of the condenser decreased with decreasing flow rate, but the integrity of the system was maintained.

Biological Control of Frankliniella occidentalis(Thysanoptera: Thripidae) on Cucumber, using Amblyseius swirskii(Acari: Phytoseiidae) (오이에서 꽃노랑총채벌레(Frankliniella occidentalis)의 생물적 방제를 위한 지중해이리응애(Amblyseius swirskii) 적용 효과)

  • Kim, Hwang-Yong;Kim, Jeong-Hwan;Kang, Seung-Ho;Lee, Yong-Hwi;Choi, Man-Young
    • Korean journal of applied entomology
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    • v.48 no.3
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    • pp.355-359
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    • 2009
  • By releasing predatory mite, Amblyseius swirskii Athias-Henriot, with 25 individuals per cucumber plant in a commercial greenhouse (1,600 $m^2$), the population of western flower thrips, Frankliniella occidentalis (Pergande), was kept under the economic threshold level. The initial thrips population of 18.3 individuals per leaf decreased to 2.1 individuals per leaf after four weeks, while the number of A. swirskii reached to 16.6 individuals per leaf. It was also observed that at a point where the thrips occurred in high density of about 34.3 individuals per leaf, A. swirskii population built up on the lower part of cucumber plant first, but as time passed the predatory mites moved upward to the top of the plant and aggregated.

A Simulation of 3-D Navigation System of the Helicopter based on TRN Using Matlab

  • Kim, Eui-Hong;Lee, Hong-Ro
    • Spatial Information Research
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    • v.15 no.4
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    • pp.363-370
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    • 2007
  • This study has been carried for the development of the basic algorithm of helicopter navigation system based on TRN (Terrain Referenced Navigation) with information input from the GPS. The helicopter determines flight path due to Origination-Destination analysis on the Cartesian coordinate system of 3-D DTM. This system shows 3-D mesh map and the O-D flight path profile for the pilot's acknowledgement of the terrain, at first. The system builds TCF (terrain clearance floor) far the buffer zone upon the surface of ground relief to avid the ground collision. If the helicopter enters to the buffer zone during navigation, the real-time warning message which commands to raise the body pops up using Matlab menu. While departing or landing, control of the height of the body is possible. At present, the information (x, y, z coordinates) from the GPS is assumed to be input into the system every 92.8 m of horizontal distance while navigating along flight path. DTM of 3" interval has been adopted from that which was provided by ChumSungDae Co., Ltd..

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Estimation Method of Infiltration Capacity for Assessment of Drainage Capacity II (배수성능 평가를 위한 침투능 산정기법에 관한 연구(II))

  • Jeong, Jisu;Shim, Jeonghoon;Lee, Dong Hyuk;Hwang, Youngcheol;Lee, Seungho
    • Journal of the Korean GEO-environmental Society
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    • v.21 no.12
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    • pp.23-28
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    • 2020
  • As a result of a suite of laboratory tests undertaken to suggest a rational method for the estimation of infiltration capacity, it is found that the infiltration rate tends to increase as the soil unit weight decreases while it tends to increase as the rainfall intensity increases. Comparative analyses for infiltration curves employing the reduction constant of initial infiltration capacity (α coefficient) that was suggested in this study has reasonably captured the time dependent variation of infiltration capacity. Consequently this study has presented an experimental model for the estimation of infiltration capacity to improve the Horton infiltration capacity curve that has been widely used for estimation of the infiltration capacity and amount of infiltration for its application to sandy soils.