• Title/Summary/Keyword: 경계 특성

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Robust Extraction of Facial Features under Illumination Variations (조명 변화에 견고한 얼굴 특징 추출)

  • Jung Sung-Tae
    • Journal of the Korea Society of Computer and Information
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    • v.10 no.6 s.38
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    • pp.1-8
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    • 2005
  • Facial analysis is used in many applications like face recognition systems, human-computer interface through head movements or facial expressions, model based coding, or virtual reality. In all these applications a very precise extraction of facial feature points are necessary. In this paper we presents a method for automatic extraction of the facial features Points such as mouth corners, eye corners, eyebrow corners. First, face region is detected by AdaBoost-based object detection algorithm. Then a combination of three kinds of feature energy for facial features are computed; valley energy, intensity energy and edge energy. After feature area are detected by searching horizontal rectangles which has high feature energy. Finally, a corner detection algorithm is applied on the end region of each feature area. Because we integrate three feature energy and the suggested estimation method for valley energy and intensity energy are adaptive to the illumination change, the proposed feature extraction method is robust under various conditions.

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Analysis of Identity of Meta Game - A Focus on Games about Games - (메타 게임의 정체성 연구 - 게임에 대한 게임을 중심으로 -)

  • Kim, So-Yeon;Han, Hye-Won
    • Journal of Korea Game Society
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    • v.18 no.2
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    • pp.99-108
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    • 2018
  • With the development of the game industry, 'games about games,' which examine the identity of game itself through a form of the game, emerged with a variety of shapes. Thus, this paper aims to suggest a definition, characteristics, and meaning of 'meta game.' Firstly, meta games strengthen the artificiality of the games and suggest procedurality through a form of the game play. Meta games also utilize the external context as a part of the games, and use the metaphor of 'labyrinth' to identify a feature of the game space. Furthermore, they emphasize intertextuality and prove that the fantasy and the reality can merge within the game world. In conclusion, meta games prove themselves to be independent expressional arts and experimental content, and suggest the potential for an alternative medium beyond formality.

A Characteristic of Freeze and Thaw on Use for Stabilized Soil in Landfill Bottom Liners (매립지 바닥층의 고화토 포설시 동결/융해의 특성)

  • Kim, Heung-Seok;Lee, Song;Lee, Jai-Young
    • Journal of the Korean GEO-environmental Society
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    • v.7 no.1
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    • pp.29-39
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    • 2006
  • Recently, Korea brings to remarkable levels about industrialization, modernization, population and development of technology. Especially, the rapidly growing from this technology has increased the burden on existing industrial waste landfills. The purpose of this research is to existing knowledge base of landfill cover liner behavior during periods freeze/thaw. Although these tests have been invaluable in clarifying the problem of freeze/thaw, extending the results of such experimental studies to prototype landfills are questionable. For this investigation, the author utilized a large scale laboratory simulation allowing inclusion of the field depth of the cover systems, layered soil profiles, rainfall simulation, a cold climate and boundary conditions similar to those encountered in the landfill. And the soil materials used stabilized soils (mixed clays, cements, and minerals) instead of clays. The bottom liners are made up of drainage layer (30cm), stabilized layer (75cm), and leach collection layer (60cm). The stabilized layers are made up of supporting layer (45cm) and impermeable layer (30cm) - consisted of $P_A$ and $P_B$ layer.

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Assessment of End Condition of Drilled Shafts Socketed into Rock by Impact Echo Test (충격반향기법을 이용한 암반근입 현장타설말뚝의 선단조건 평가)

  • 김형우;김동수;김원철
    • Journal of the Korean Geotechnical Society
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    • v.18 no.4
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    • pp.21-32
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    • 2002
  • Small and full scale model tests were performed to obtain the transient responses of shafts subjected to elastic impact by impact-echo test. Four end conditions of drilled shafts were considered: (1) free, (2) fixed, (3) rock-socketed, and (4) soft bottom. In small scale model tests, mock-up shafts were fabricated to simulate these four drilled shafts using poly-urethane and plastic material. Additionally, skin frictions between shaft and rock were changed to find out the effect of side contact on dynamic responses. All impact responses were tested in the air. Subsequently, full scale model tests were also carried out on concrete shafts that were in free and rock-socketed condition. The end conditions of the drilled shafts could be identified with good reliability by the waveforms from both small and full scale model tests. The results obtained in this study will provide an improved understanding of the impact responses for end conditions, especially for rock-socketed drilled shafts that are frequently designed and built in Korea.

Fabrication of the Corrugated Feed Horn for 85~115GHz Radio Telescope System (85~115GHz 전파망원경용 컬러게이트 급전 혼 제작)

  • Son, Tae-Ho;Han, Seog-Tae
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.19 no.6
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    • pp.640-646
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    • 2008
  • Design procedure of corrugated horn antenna for the mm-wave frequency range is presented, and hybrid condition in horn is calculated. In this paper, corrugate profiles of horn which satisfy both transition to balanced hybrid condition and fabrication possibility under the mm-wave short wavelength are obtained. Electromagnetic fields inside horn and corrugation are derived by the cylindrical mode theory. Propagation characteristics in the horn are calculated by the mode impedance matching method with boundary conditions, and radiation fields are obtained by the Kirchhoff-Hyugen principle to the horn aperture fields. A mm-wave corrugated horn antenna which operates on $85{\sim}115GHz$ is fabricated by electric forming method. Measurements show that VSWR is under 1.3:1 over whole band and the half power beamwidth on radiation pattern 9.2, 9.16 and 9.02 degree on 85, 100 and 110 GHz are agree well with theoretical calculation.

다채널 표면 플라즈몬 공명 영상장치를 이용한 자기조립 단분자막의 표면 분석

  • Pyo, Hyeon-Bong;Sin, Yong-Beom;Yun, Hyeon-Cheol
    • 한국생물공학회:학술대회논문집
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    • 2003.04a
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    • pp.74-78
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    • 2003
  • Multi-channel images of 11-MUA and 11-MUOH self-assembled monolayers were obtained by using two-dimensional surface plasmon resonance (SPR) absorption. Patterning process was simplified by exploiting direct photo-oxidation of thiol bonding (photolysis) instead of conventional photolithography. Sharper images were resolved by using a white light source in combination with a narrow bandpass filter in the visible region, minimizing the diffraction patterns on the images. The line profile calibration of the image contrast caused by different resonance conditions at each points on the sensor surface (at a fixed incident angle) enables us to discriminate the monolayer thickness in sub-nanometer scale. Furthermore, there is no signal degradation such as photo bleaching or quenching which are common in the detection methods based on the fluorescence.

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Local Convective Mass Transfer and Flow Structure Around a Circular Cylinder with Annular Fins (환상핀이 부착된 원봉 주위의 3차원 박리 유동구조 및 물질전달 특성 해석)

  • 박태선;성형진
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.6
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    • pp.2132-2146
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    • 1991
  • Extensive experiments were carried out to investigate the mass transfer and flow structures around a circular cylinder with annular fins in crossflow. The naphthalene sublimation method was employed to measure the circumferential and longitudinal variations of mass transfer from the circular cylinder between annular fins and H is the height of the fin from the cylinder surface. A remarkable enhancement of mass transfer due to the horseshoe vortices was observed near the corner junction between the annular fin and circular cylinder. The present results indicate that the local circumferential Sherwood number shows the higher values on the front stagnation point. The maximum augmentation of mass transfer rate at the center of cylinder is found near L/H-0.15 due to the separation bubble along the annular fins. The secondary flows, which are the corner vortices V2 and V3 near the end wall of the annular fin, are fairly predicted from the distributions of local Sherwood number in the spanwise direction. The average Sherwood number of overall surface at L/H=0.15 is larger 2.0 times than that of without annualr fins. The correlations of total average mass transfer rate with L/H and Re$_{L}$ can also be obtained.d.

Analysis of Three-Dimensional Profile of Bacterial Colony and Visualization of Fluidic Biofilm Using Fluorescent Microbeads (형광 미세입자를 이용한 박테리아 군집의 3차원 형상 분석 및 유동성 생물막의 가시화)

  • Kim, Kyung-Hoon;Park, Eun-Jung;Kim, Jung-Kyung
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.11
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    • pp.1119-1126
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    • 2012
  • The collective behavior of bacteria plays an important role in biofilm development. In this study, the fluidic properties of biofilms formed in Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) colonies were compared by visualizing 200-nm fluorescent beads that were initially embedded in an agar plate and distributed spontaneously on the upper surface of the growing colonies. We conducted experiments to measure the three-dimensional profile of the E. coli colony using fluorescent microbeads that did not flow in the colony. Vortical flow patterns near the edge of the B. subtilis colony were observed clearly by tracking the movement of the beads in the biofilm of the colony. The present study should be the first step toward determining the effect of fluidic biofilms on the growth and swarming dynamics of bacteria.

Numerical analysis of natural convection from a horizontal isothermal surface immersed in water near its density extremum (최대밀도점 부근의 물속에 잠겨있는 수평등온도면에 의하여 야기되는 자연대류의 수치해석)

  • 김병하;조승환;유갑종
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.1
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    • pp.197-206
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    • 1990
  • Numerical results of heat transfer from a horizontal isothermal surface are presented for wall temperature T$_{w}$ = 0 .deg. C and ambient water temperature, T$_{\infty}$, from 1 .deg. C to 15 .deg. C. They include streamlines, temperature profiles, local heat transfer coefficients and average Nusselt numbers for the entire flow fields. For a upward-facing horizontal isothermal surface, the results show steady two dimensional flow regimes for T$_{\infty}$ .leg. 4.4 .deg. C, but no solution was obtained above T$_{\infty}$ = 4.4 .deg. C. For a downward-facing horizontal isothermal surface, the flow regimes are steady two dimensional flow for T$_{\infty}$ .geq. 4.9 .deg. C, and the numerical calculation was failed below this ambient water temperature. The mean Nusselt number has its maximum value at about T$_{\infty}$ = 3.4 .deg. C for upward-facing horizontal isothermal surface. For the case of downward-facing horizontal isothermal surface, the mean Nusselt number increases as the ambient water temperature increases.es.s.s.

Unsteady Thermoelasic Deformation and Stress Analysis of a FGM Rectangular Plate (경사기능재료 사각 판의 비정상 열 탄생변형과 응력해석)

  • Kim, Kui-Seob
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.32 no.8
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    • pp.91-100
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    • 2004
  • A Green's function approach is adopted for analyzing the thermoelastic deformations and stresses of a plate made of functionally graded materials(FGMs). The solution to the 3-dimensional unsteady temperature is obtained by using the laminate theory. The fundamental equations for thermoelastic problems are derived in terms of out-plane deformation and in-plane force, separately. The thermoelastic deformation and the stress distributions due to the bending and in-plane forces are analyzed by using a Green's function based on the Galerkin method. The eigenfunctions of the Galerkin Green's function for the thermoelastic deformation and the stress distributions are approximated in terms of a series of admissible functions that satisfy the homogeneous boundary conditions of the rectangular plate. Numerical analysis for a simply supported plate is carried out and effects of material properties on unsteady thermoclastic behaviors are discussed.