• Title/Summary/Keyword: Shading Function

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Temperature Patterns in Concrete Pavements at Very Early Ages (콘크리트 도로 포장의 초기 온도 분포 분석)

  • Kim, Seong-Min;Nam, Jeong-Hee
    • International Journal of Highway Engineering
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    • v.7 no.3 s.25
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    • pp.79-91
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    • 2005
  • The temperature patterns in Portland cement concrete (PCC) pavements were measured and comprehensively analyzed from the beginning of the concrete placement based on the temperature measurement technique developed using innovative and inexpensive temperature measurement sensors. The temperature measurements in PCC pavements were taken at several different locations forvarious slab thicknesses. The concrete temperature patterns in the vertical and longitudinal directions of the pavement were analyzed and the effects of the pavement surface reflectivity, shading, and covering on the concrete temperatures were evaluated. The results of this study showed that the significant differences in the maximum concrete temperatures on the placement day were observed according to the concrete placement time. Since the zero-stress temperature is a function of the maximum concrete temperature on the placement day, the placement time would be an important factor that affects the behavior and performance of concrete pavements. The surface conditions of the pavement, such as the surface color, shading, and covering also affected the temperature patterns in PCC pavements significantly.

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Daylight Assessment of Venetian Blind by Shading Heights and Slat Angles (베네시안 블라인드의 높이와 슬랫각도 조절에 따른 계절별 실내주광분포 분석)

  • Shin, Hwa-Young;Kim, Gon;Kim, Jeong Tai
    • KIEAE Journal
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    • v.11 no.2
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    • pp.105-111
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    • 2011
  • Aims of this study is to investigate the daylighting control strategy of venetian blind system was performed as a function of ratio of shading height to window and slat angles in the preliminary stage of the parametric study. Floor-to-ceiling window walls of living spaces are used widely in apartment buildings since the Korean government has legally allowed elimination of the balcony area. Enlarging living area by balcony elimination, the larger glass area of window is exposed to the direct sunlight. As a common sunlight controlling device, blind system can be used in all orientations and all latitudes and it may obstruct, absorb, reflect and transmit solar radiation to building by proper adjusting. However, blind system can produce discomfort in occupant and less energy efficiency, if it has not been controlled optimally. The simulation model was based on the unit module of typical living space with balcony elimination. The room dimension was $6.0m(w){\times}6.9m(d){\times}2.7m(h)$ with floor to ceiling height of 2.5m. The blind system was simulated at five slat angles (horizontal, $30^{\circ}$, $45^{\circ}$ upward and downward tilted) and the four ratio of shading height to window (fully closed, partly opened, no-blind) using the Desktop RADIANCE 2.0 program. The series of simulation results indicates that the advantages of available daylight and outside of view can be improved by proper adjusting blind system.

Shape from Shading using the Hierarchical basis Function and Multiresolution Images (계층적 기저함수와 다해상도 영상을 이용한 영사응로부터 물체의 형상복구)

  • 이승배;이상욱;최종수
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.29B no.11
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    • pp.73-84
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    • 1992
  • In this paper, an algorithm for recovering the 3-D shape from a single shaded image is proposed. In the proposed algorithm, by using the relation between the height and surface gradient (p, q), a set of linear equations is derived from the linearized reflectance function. Then the 3-D surface is recovered by employing the conjugate gradient technique. In order to improve the convergence speed of the solution, we also employ the hierarchical basis function and multiresolution images in the algorithm. A method for determining the regularization parameter, which is determined by trial and error in the conventional approach, is also introduced. In addition, the proposed algorithm attempts to recover the 3-D surface without requiring the boundary conditions, making it suitable for a real-time implementation. Simulation results for real image as well as synthetic image are provided to demonstrate the performance of the proposed algorithm.

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Obtaining 3-dimensional shape of hybrid reflectance surfaces using indirect diffuse illumination (간접 확산 조명을 이용한 혼성반사 표면의 3차원 형상 취득)

  • 김태은;안호근;최종수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.2
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    • pp.301-312
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    • 1996
  • A new approach is presented for recovering the 3-D shape from shading image. Photometric Stereo Method (PSM) is generally based on the direct illumination. In this paper, the reflectance function is derived by introduceing the indirect diffuse illumination in PSM and then applied to hybrid reflectance model which consists fo two components; the Lambertian reflectance and the speclar reflectance. Under the hybrid reflectance model and the indirect diffuse illumination circumstances, the 3-D shape of object can be recovered from the suface normal vector extracted from the surface roughness, the surface reflectance ratio, and the intensity value of a pixel. This method is rapid because of using the reference table and simplifies the restriction condition about the reflectance function existing in prior studies. The recovery efficiency in our method is better than that in prior studies. Also, this method is applied to various types of surfaces by defining general reflectance function.

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Detection of Speaker Position for Robot Using HRTF (머리전달함수를 이용한 로봇의 화자 위치 추정)

  • Hwang, Sung-Mook;Park, Youn-Sik;Park, Young-Jin
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.637-640
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    • 2005
  • We propose a sound source localization method using the Head-Related-Transfer-Function (HRTF) to be implemented in a given platform. HRTFs contain not only the information regarding proper time delays but also phase and magnitude distortions due to diffraction and scattering by the shading object. Therefore, a set of HRTFs for any given platform provides a substantial amount of information as to the whereabouts of the source. In this study, we introduce new phase criterion in order to find the sound source location in accordance with the HRTF database empirically obtained in an anechoic chamber with the given platform. Using this criterion, we analyze the estimation performance of the proposed method in a household environment.

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Experimental Study on the Thermal Effect of BIPV Modules Depending on the Ventilation Type of PV Module Backside (후면 환기조건에 따른 건물외피용 태양광발전(BIPV) 모듈의 열적 영향에 관한 실험연구)

  • Yoon, Jong-Ho;Kim, Jae-Ung
    • Journal of the Korean Solar Energy Society
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    • v.26 no.1
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    • pp.81-89
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    • 2006
  • Building integrated photovoltaic (BIPV) system operates as a multi-functional building construction material. They not only produce electricity, but also are building integral components such as facade, roof, window and shading device. On the other hands lots of architectural considerations should be reflected such as Installation position, shading, temperature effect and so on. As PV modules function like building envelope in BIPV, combined thermal and PV performance should be simultaneously evaluated This study is on the combined thermal and PV performance evaluation of BIPV modules. The purpose of this study is to investigate a temperature effect of PV module depending on the ventilation type of PV module backside. Test cell experiment was performed to identify the thermal and power effect of PV modules. Measurement results on the correlation of temperature and power generation were obtained. Those results can be utilized for the development of optimal BIPV installation details in the very early design stage.

PBR(Physically based Render) simulation considered mathematical Fresnel model for Game Improvement (효율적 게임개선을 위한 프레넬수학모델의 PBR 시뮬레이션)

  • Kim, Seongdong
    • Journal of Korea Game Society
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    • v.16 no.1
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    • pp.111-118
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    • 2016
  • This paper proposes the mathematical model of Fresnel effect used to illuminate and simulate a surface character model for defense game play. The term illumination is used to represent the process by which the amount of light reaching a surface character model used on game play is determined. The character surface shaders generally use a mathematical model to predict how light will reflect on triangles. The shading normally represents the methods used to determine the color and intensity of light reflected toward the viewer for each pixel representing the character surface model of the game. This model computes the reflection and transmission coefficients and compares simulated results to the Fresnel equations for the real game improvement.

Proposal of Makeup's Function on the Metaverse Digital Platform - Focusing on Zepeto - (메타버스 디지털 플랫폼의 메이크업 기능 제안 - 제페토를 중심으로 -)

  • Se Mi Nam;Eun Sil Kim
    • Fashion & Textile Research Journal
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    • v.25 no.6
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    • pp.739-744
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    • 2023
  • With the popularization of 5G networks and the development of AI (artificial intelligence) technology, Metaverse, which creates production capacity by combining virtual space and reality, is attracting attention. In this study, we searched for makeup applications with more than 100 million downloads from October 11, 2020 to November 3, 2020 through the Google Play Store. As a result of the search, four applications were found: YouCam Makeup, YouCam Perfect, Beauty Plus, and Sweet Snap. Based on the functions provided by the four applications, we attempted to suggest makeup functions applicable to Zepeto's avatar. Functions for the eyes (eyeliner, eyelashes, mascara, eye shadow, eye shape, eyebrow shape, lenses, double eyelids), functions for the nose (nose shape), functions for the mouth (lipstick, lip shape, smile function) ) Functions corresponding to the facial contour (contour, skin foundation, blusher, shading, highlighter, face painting, theme makeup) and functions corresponding to the body (body adjustment) were proposed. This study is the first in the beauty field to propose a method of applying the functions of the Metaverse platform as the importance of digital platforms is highlighted, and is the first to propose a makeup function applied to the Metaverse so that it can be used as important basic data in the future.

Image based Shading Techniques for Surfaces with Irregular and Complex Textures Formed by Heterogeneous Materials (이종물질에 의해 복잡한 불규칙 무늬가 형성된 물체 표면의 영상 기반 셰이딩 기법)

  • Lee, Joo-Rim;Nam, Yang-Hee
    • The Journal of the Korea Contents Association
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    • v.10 no.1
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    • pp.1-9
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    • 2010
  • In this paper we present a shading technique for realistic rendering of the surfaces with irregular and complex textures using a single photograph. So far, most works have been using many photographs or special photographing equipment to render the surfaces with irregular and complex textures as well as dividing texture regions manually. We present an automatic selection method of the region segmentation techniques according to properties of materials. As our technique produces a reflectance model and the approximated Bidirectional Reflection Distribution Function(BRDF) parameters, it allows the recovery of the photometric properties of diffuse, specular, isotropic or anisotropic textured objects. Also it make it possible to present several synthetic images with novel lighting conditions and views.

Water Physiology of Panax ginseng Charcteristics of reproductit.e organs and precipitation rate and humidity of shade system. (인삼의 수분생리 II. 생식기관의 특성과 일복의 누수량 및 습도)

  • Park, Hoon
    • Journal of Ginseng Research
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    • v.6 no.1
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    • pp.84-99
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    • 1982
  • Water content and its seasonal change in reprodltctive organs were reviewed in relation to cultivation practice s. Precipitati on and humidity under shade roof were reviewed in relation to shading ,jystem and environmental factors. High water content of reproductive organs suggests vulnerability to water stress during reproductive growth stage. Watering during dehisconce treat menu seems to keep optimum temperature but cnoventional practice seems to be too often In watering. Information effe on water physiology of seeds is too rare to develop seed storing method and ctive seed use. Dehiscent mechanism was considered in terms of water absorption of embryo. Precipitation rate of conventional shade roof reaclled to 38% and at line level 50% and varied with shade patterns. Precipitation rate under shade has been investigated for itself but should be investigated in relation to light intensity and soil moisture content Relative humidity under shade depends mainly on air humidity and soil moisture, considerably on shade materials and lithe on pole height, bed width or plant density. Since relative humidity was lower in afternoon it was often less than 50% even in summer with high temperature suggesting possible disorder of phi biological function especially in photosynthesis. More information was needed on optimum humidity for productive physiological function of leaf.

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