• 제목/요약/키워드: Bottom-up method

검색결과 406건 처리시간 0.026초

농촌마을 유형별 주민역량교육에 관한 연구 - 색깔있는 마을 만들기를 중심으로 - (A Study on Residents' Competency Education Needs of Rural Village Types - Focused on the Building up Rural Village Revitalization -)

  • 권지윤;김은수;배성의
    • 농촌지도와개발
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    • 제22권1호
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    • pp.1-14
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    • 2015
  • The rural development business policy of our country is seeking to change the existing top-down development method to the bottom-up development one. As residents' participation in village development is being focused, residents competence has come to be considered important. Thus, this study classified the village type by investigating resources of the target villages in Chungcheongnam-do through a rural forum, and examined education needs targeting the residents of the villages through a survey. The preferred the types, of education according to the types of farm villages were examined. It is needed to raise the efficiency of enhancing village development competence by regarding execution of the priority of competence enhancing education as a practical strategy. This also can be used as the baseline data for rural catchment typing research.

언덕지형을 지나는 유동에 관한 연구 (Wind Flow over Hilly Terrain)

  • 임희창;김현구;이정묵;경남호
    • 한국대기환경학회지
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    • 제12권4호
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    • pp.459-472
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    • 1996
  • An experimental investigation on the wind flow over smooth bell-shaped two-dimensional hills with hill slopes (the ratio of height to half width) of 0.3 and 0.5 is performed in an atmospheric boundary-layer wind tunnel. Two categories of the models are used in the present investigation; six two-dimensional single-hills, and four continuous double-hills. The measurements of the flow field and surface static-pressure distribution are carried out over the Reynolds number (based on the hill height) of 1.9 $\times 10^4, 3.3 \times 10^4, and 5.6 \times 10^4$. The velocity profiles and turbulence characteristics are measured by the pitot-tube and X-type hot-wire anemometer, respectively. The undisturbed boundary-layer profile on the bottom surface of the wind tunnel is reasonably consistent with the power-law profile with $\alpha = 7.0 (1/\alpha$ is the power-law exponent) and shows good spanwise uniformities. The profiles of turbulent intensity are found to be consistent along the centerline of the wind tunnel. The measured non-dimensional speed-up profiles at the hill crest show good agreements with the predictions of Jackson and Hunt's linear theory. The flow separation occurs in the hill slope of 0.5, and the oil-ink dot method is used to find the reattachment points in the leeside of the hill. The measured reattachment points are compared with the numerical predictions. Comparisons of the mean velocity profiles and surface pressure distributions between the numerical predictions and the experimental results show good agreements.

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복합 나노미터 패턴 도광판의 광특성 (Optical Characteristics of the LGP with Nanometer-patterned Sizes on Its Both Surfaces)

  • 홍진수;김창교;이병욱;김경래
    • 제어로봇시스템학회논문지
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    • 제14권6호
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    • pp.530-534
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    • 2008
  • The LGP with nanometer structures resulted in enhancement of optical efficiency. Its fundamental mechanism is to recycle the polarized light via one round-trip through QWP(Quarter-wave Plate) but the maximum efficiency to reach with this method is limited up to 2. To get the larger efficiency than this a LGP with 1D PC(one-dimensional photonic crystal) nanometer-patterned on its top and bottom surfaces is suggested. For its optimum design the computer simulation is performed and suggests a grating that the spatial frequency between adjacent patterns is 500nm, its height 250nm, duty cycle 50%, and its cross section is rectangular. The angles of transmitted light are nearly the same as the results expected from the generalized Snell's law. Thus the Mathematica code, developed in this experiment, will be applied to designing the optimized LGP. The LGP with nanometer-patterened 1D PC LGP on its both surfaces shows the enhancement of transmitted intensity distribution up to 5.7 times.

Experimental study on flexural strength of reinforced modular composite profiled beams

  • Ahn, Hyung-Joon;Ryu, Soo-Hyun
    • Steel and Composite Structures
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    • 제8권4호
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    • pp.313-328
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    • 2008
  • This study attempts to suggest bending reinforcement method by applying bending reinforcement to composite profile beam in which the concept of prefabrication is introduced. Profile use can be in place of framework and is effective in improvement of shear and bending strength and advantageous in long-term deflection. As a result of experiment, MPB-CB2 with improved module had higher strength and ductility than the previously published MPB-CB and MPB-LB. In case of bending reinforcement with deformed bar and built-up T-shape section based on MPB-CB2, the MPB-RB series reinforced with deformed bar were found to have higher initial stiffness, bending strength and ductility than the MPB-RT series. The less reinforcement effect of the MPB-RT series might be caused by poor concrete filling at the bottom of the built-up T-shape. In comparison between theoretical values and experimental values using minimum yield strength, the ratio between experimental value and theoretical value was shown to be 0.9 or higher except for MPB-RB16 and MPB-RT16 that have more reinforcement compared to the section, thus it is deemed that the reinforced modular composite profiled beam is highly applicable on the basis of minimum yield strength.

서모컬러를 이용한 회전 디스크의 레이저 온도 측정 (Laser Based Temperature Measurement of Rotating Disk Using Thermocolor)

  • 나원휘;유재천
    • 센서학회지
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    • 제22권1호
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    • pp.49-53
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    • 2013
  • In this paper, we proposed a laser-based non-contact temperature measuring method for high speed rotating polycarbonate (PC) disk using transparency change of thermocolor. The thermocolor has abilities to change color and transparency due to a change in temperature. The thermocolor is applied on one side of polyvinylidene fluoride (PVDF) membrane. The thermocolor applied membrane is attached to inside of reaction chamber in disk. An optical system consisted of a laser beam radiator and a laser photometer is installed. Laser is irradiated at the bottom side of disk and the transmitted laser beam is detected by the laser photometer at the opposite side of disk. During the disk is rotating, laser is irradiated and detected simultaneously. The laser photometer senses the transmitted laser power and generates voltage as output. The temperature of disk can be detected during the disk is rotating up to 3000 RPM.

Fast Intraframe Coding for High Efficiency Video Coding

  • Huang, Han;Zhao, Yao;Lin, Chunyu;Bai, Huihui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권3호
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    • pp.1093-1104
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    • 2014
  • The High Efficiency Video Coding (HEVC) is a new video coding standard that can provide much better compression efficiency than its predecessor H.264/AVC. However, it is computationally more intensive due to the use of flexible quadtree coding unit structure and more choices of prediction modes. In this paper, a fast intraframe coding scheme is proposed for HEVC. Firstly, a fast bottom-up pruning algorithm is designed to skip the mode decision process or reduce the candidate modes at larger block size coding unit. Then, a low complexity rough mode decision process is adopted to choose a small candidate set, followed by early DC and Planar mode decision and mode filtering to further reduce the number of candidate modes. The proposed method is evaluated by the HEVC reference software HM8.2. Averaging over 5 classes of HEVC test sequences, 41.39% encoding time saving is achieved with only 0.77% bitrate increase.

종방향 압축하중을 받는 선체 유공보강판의 최종강도 거동에 관한 연구 (Ultimate Strenth Behaviour for Perforated Stiffened Panels under Longitudinal Compressive Load)

  • 고재용;박주신;이계희
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2005년도 춘계 학술발표회 논문집
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    • pp.592-600
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    • 2005
  • Ship have cutout inner bottom and girder and floor etc. Ship's structure is used much, and structure strength must be situated, but establish new concept when high stress interacts sometimes fatally the area. There is no big problem usually by aim of weight reduction, a person and change of freight, piping etc.. Because cutout's existence grow up in this place, and elastic buckling strength by load causes large effect in ultimate strength. Therefore, stiffened perforated plate considering buckling strength and ultimate strength is one of important design criteria which must examine when decide structural concept at initial design. Therefore, md, reasonable buckling strength about stiffened perforated plate need to ultimate strength limited design . Calculated ultimate strength varied several web height and cutout's dimension, and thickness in this investigated data. Used program(ANSYS) applied F.E.A code based on finite element method

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수직적 재사용을 위한 방법론 연구 (The Study of Software Analysis Process for Vertical Reuse)

  • 방정원
    • 한국컴퓨터정보학회논문지
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    • 제9권3호
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    • pp.103-107
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    • 2004
  • 소프트웨어의 재사용은 생산성 향상, 소프트웨어의 신뢰성 향상, 소프트웨어 개발기간 단축, 개발비용 절감, 시스템 관련 정보 공유 등의 장점을 지닌다. 수직적 재사용은 하나의 영역 또는 응용 분야에서만 재사용함으로서, 높은 이해성으로 인해 재상용의 신뢰성을 높일 수 있는 방법이다. 소프트웨어 시스템을 개발할 때 사용되는 정보들을 재사용을 목적으로 분류하여, 결과물들을 추상화하는 상향식 방법을 이용하여 단순 코드의 재사용에서 벗어나 비형식적인 자료들을 포함해 모든 정보를 사용 가능하게 할 수 있다.

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단면도를 이용한 3차원 파라메트릭 설계

  • 김병인;김광수
    • 대한산업공학회지
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    • 제20권3호
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    • pp.35-53
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    • 1994
  • Orthographic views ore traditionally used for engineering drawings. This paper presents a methodology for 3D parametric design using orthographic views. The parametric design technique, which is used to design 2D orthographic views, is based on production rules. In the production rule-base, several view interrelation rules and over 50 geometric rules are included. An efficient algorithm is also developed to expedite the reasoning process. For 3D object construction from orthographic views, the approach known as bottom-up geometrical approach is used. The approach consists of 4 steps : 1) generation of wire-frame, 2) construction of face from wire frame, 3) formation of 3D subobjects from faces, and 4) construction of final 3D objects. Curvilinear solids as well as planar solids can be constructed. A method of converting existing 2D CAD data to parametric 3D CAD data is also presented.

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기능 전개를 활용한 기계류 부품의 Fault Tree 구성에 관한 연구 (Fault Tree Construction Method using Function Deployments of Machine Parts)

  • 하성도;이언경;강달모
    • 한국신뢰성학회:학술대회논문집
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    • 한국신뢰성학회 2001년도 정기학술대회
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    • pp.257-263
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    • 2001
  • In the analysis of product reliability, the fault tree is widely used since it shows the interrelations of the faults that lead to the product fault. A top-down approach based on experts’ experience is commonly used in the fault tree construction and the trees often take different forms depending on the intent of the analyst. In this work it is studied how to construct fault trees with the utilization of function trees obtained from analyzing the functions and sub-functions of products in order to suggest a generic way of fault tree construction. The function tree of a product is obtained by analyzing basic functions comprising the product main function in a bottom-up approach so that it enables to construct an objective fault tree. The fault tree for a scroll compressor is shown as an example.

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