• Title/Summary/Keyword: Shading System

Search Result 264, Processing Time 0.024 seconds

Experiment on measures of heat collection for passive solar water wall systems that provide heat storage and natural lighting control (축열과 채광조절을 겸한 자연형 태양열 수벽시스템의 집열방식별 성능실험)

  • Oh, Young-hoon;Choi, Ji-eun;Lee, Chul-sung;Yoon, Jong-ho
    • KIEAE Journal
    • /
    • v.16 no.4
    • /
    • pp.63-69
    • /
    • 2016
  • Purpose: This preliminary study investigated a potential of the water wall systems that provide heat storage and natural lighting control simultaneously. Method: In order for transparency of the water wall to be controlled, the study first proposed two measures: to adjust transparency of the water wall; to control transparency of water wall surface. The performance of two measures then was verified and compared by experiments. In addition, a trade-off between heat collect and heat storage resulting from using additive for adjusting transparency was investigated. Result: The experiment showed that the two measures are similar in performance. The investigation of trade-off relation showed the additive should have the same heat storage as the water to prevent decrease in thermal performance of the water wall. As an economical measure to control transparency of the water wall, this study suggested a measure of secondary heat transfer systems using shading device that first absorbs solar radiation and then transfers heat to the water wall. The experiment show that performance of the proposed measure is similar to controlling transparency of water wall surface. In conclusion, it is expected that the performance of the water wall can be economically maximized by using the proposed mean in terms of heating, cooling and lighting energy saving.

The a-Si:H/poly-Si Heterojunction Solar Cells

  • Kim, Sang-Su;Kim, do-Young;Lim, Dong-Gun;Junsin Yi;Lee, Jae-Choon;Lim, Koeng-Su
    • Journal of Electrical Engineering and information Science
    • /
    • v.2 no.5
    • /
    • pp.65-71
    • /
    • 1997
  • We present heterojunction solar cells with a structure of metal/a-Si:H(n-i-p)/poly-Si(n-p)/metal for the terrestrial applications. This cell consists fo two component cells: a top n-i-p junction a-Si:Hi cell with wide-bandgap 1.8eV and a bottom n-p junction poly-Si cell with narrow-bandgap 1.1eV. The efficiency influencing factors of the solar cell were investigated in terms of simulation an experiment. Three main topics of the investigated study were the bottom cell with n-p junction poly-Si, the top a-Si:H cell with n-i-p junction, and the interface layer effects of heterojunction cell. The efficiency of bottom cell was improved with a pretreatment temperature of 900$^{\circ}C$, surface polishing, emitter thickness of 0.43$\mu\textrm{m}$, top Yb metal, and grid finger shading of 7% coverage. The process optimized cell showed a conversion efficiency about 16%. Top cell was grown by suing a photo-CVD system which gave an ion damage free and good p/i-a-Si:H layer interface. The heterojunction interface effect was examined with three different surface states; a chemical passivation, thermal oxide passivation, and Yb metal. the oxide passivated cell exhibited the higher photocurrent generation and better spectral response.

  • PDF

Development of 3-D Web Graphic Library Using Java (자바를 이용한 3차원 웹 그래픽 라이브러리의 개발)

  • Jeong, Gab-Joong
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.9 no.8
    • /
    • pp.1709-1715
    • /
    • 2005
  • This paper describes the development of 3-D web graphic library for dynamic web graphic design. The 3-D web graphic library developed in this per supports creation of 3-D objects like cube and sphere objects, elimination of hidden line and surface, and the shading of diffuse and specular reflections. It provides, in drawing, perspective projection of an object depth first sort of multiple objects, and wire frame and solid models. It also supports texture mapping function for realistic and dynamic web application in application software. Each created 3-D object gives functions for the scaling, translation, and rotation of itself. It can be used for the development of dynamic web application software and the advertisement of information for business and tourism as a 3-D web graphic library engine. It is written in 'Java' language and runs on web browsers with Java virtual machine without any dependancy of client computer system.

A Study on the Recognition of Polyhedral Object using 3-D Information (3차원 정보를 이용한 다면체의 물제인식에 관한 연구)

  • 김영일;우동임;백남칠;우광방
    • The Transactions of the Korean Institute of Electrical Engineers
    • /
    • v.38 no.6
    • /
    • pp.458-469
    • /
    • 1989
  • A measurement method is proposed which finds 3-D position and attitude of a known polyhedra utilizing shading information. Through the systematic interpretation of relations between polyhedra and its image as well as shadow image and also the determination of candidate position, 3-D information with respect to vertex of polyhedra is extracted. Following preprocessing of this information, the image of polyhedra is represented in terms of the scene with positioned object and the correspondence is searched by means of matching process between a scene description of the object and the correspondence is searched by means of matching process between a scene description of the object and a model description stored in data-base. In the experiments, initially 3-D information is employed to select several model regions, and objects are recognized through matching process with respect to scene regions. The results demonstrate that the recognition system performs with a high efficiency by proper selection of the threshold values.

3-D Facial Animation on the PDA via Automatic Facial Expression Recognition (얼굴 표정의 자동 인식을 통한 PDA 상에서의 3차원 얼굴 애니메이션)

  • Lee Don-Soo;Choi Soo-Mi;Kim Hae-Hwang;Kim Yong-Guk
    • The KIPS Transactions:PartB
    • /
    • v.12B no.7 s.103
    • /
    • pp.795-802
    • /
    • 2005
  • In this paper, we present a facial expression recognition-synthesis system that recognizes 7 basic emotion information automatically and renders face with non-photorelistic style in PDA For the recognition of the facial expressions, first we need to detect the face area within the image acquired from the camera. Then, a normalization procedure is applied to it for geometrical and illumination corrections. To classify a facial expression, we have found that when Gabor wavelets is combined with enhanced Fisher model the best result comes out. In our case, the out put is the 7 emotional weighting. Such weighting information transmitted to the PDA via a mobile network, is used for non-photorealistic facial expression animation. To render a 3-D avatar which has unique facial character, we adopted the cartoon-like shading method. We found that facial expression animation using emotional curves is more effective in expressing the timing of an expression comparing to the linear interpolation method.

Growth Characteristics of Ginseng Seedling Transplanting by Self Soil Nusery, Nursery or Hydroponic Culture on Main Field (토직, 상토 및 양액육묘에 의해 생산된 묘삼의 본포 이식 후 생장특성)

  • Park, Hong Woo;Song, Jeong Ho;Kwon, Ki Bum;Lee, Ueong Ho;Son, Ho Jun
    • Korean Journal of Medicinal Crop Science
    • /
    • v.25 no.4
    • /
    • pp.238-243
    • /
    • 2017
  • Background: The production method of ginseng seedlings for ginseng cultivation is very important to ensure healthy rooting system as well as high quality, and yield of the resultant plants. This study was carried out to compare the growth characteristics of 2-year-old ginseng plants that were produced from seedlings grown in self soil nursery (SSN), nursery soil (NS) or hydroponic culture (HC). Methods and Results: The shading prop used was composed of four-layered 4 polyethylene (blue 3 + black 1) shade screen. The management of main field was done by inserting oil cake (1,200 kg/10 a) and then allowing Sudan grass to grow for a year. Seedling transplantation was carried out on April 6. Root growth was measured on October 25. Root weight was observed to be excellent at 6.0 g, following SSN transplantation. Root length was 21.2 cm for HC seedlings, but these plants had a physiological disorder (i.e., rusty root), in 83.5% plants of this treatment. The ratio of PD/PT (protopanaxadiol saponins / protopanaxatriol saponins) was higher in NS seedlings. Plant analysis revealed that Fe content was lower in HC seedlings with high rustiness. The growth of 2-years-old ginseng was different following these varying seedling cultivation methods, but seedlings from NS were not different from those grown in SSN. Conclusions: For the propagation of 2-year-old ginseng plants, NS seedlings may be a good substitute for SSN seedlings.

Optimal Cutting Conditions for the Production of Cudriania tricuspidata Bureau (꾸지뽕나무 묘목생산을 위한 최적 꺽꽂이 조건)

  • Sung, Gyoo Byung;Kim, Ki Young;Kim, Hyun Bok;Ji, Sang Duk
    • Journal of Sericultural and Entomological Science
    • /
    • v.50 no.2
    • /
    • pp.166-170
    • /
    • 2012
  • Most of Cudriania tricuspidata Bureau saplings in Korea have been produced by crown division. But the production of Cudriania tricuspidata B. saplings by this method is very low in efficiency and in uniformity. Therefore, to develop Cudriania tricuspidata B. saplings production system by cutting method which is suitable for mass production, several conditions on rooting and growth of cuttings were investigated. The rooting ability of cuttings varied according to temperature on the bed, length, thickness of the hard wood cutting and rooting agent application. Of different concentration of rooting agent, the 5,000 ppm of 1-naphthalenacetic acid(NAA) and Indole butyric acid(IBA) were found to be the highest in rooting of hardwood cuttings; other concentration were in order as follows; 2,500, 1,000 and 10,000 ppm in concentration of rooting agents. The shading ratio of polyethylene film showed the highest rooting ratio of the softwood cuttings at 55%.

Modeling Soil Temperature of Sloped Surfaces by Using a GIS Technology

  • Yun, Jin I.;Taylor, S. Elwynn
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.43 no.2
    • /
    • pp.113-119
    • /
    • 1998
  • Spatial patterns of soil temperature on sloping lands are related to the amount of solar irradiance at the surface. Since soil temperature is a critical determinant of many biological processes occurring in the soil, an accurate prediction of soil temperature distribution could be beneficial to agricultural and environmental management. However, at least two problems are identified in soil temperature prediction over natural sloped surfaces. One is the complexity of converting solar irradiances to corresponding soil temperatures, and the other, if the first problem could be solved, is the difficulty in handling large volumes of geo-spatial data. Recent developments in geographic information systems (GIS) provide the opportunity and tools to spatially organize and effectively manage data for modeling. In this paper, a simple model for conversion of solar irradiance to soil temperature is developed within a GIS environment. The irradiance-temperature conversion model is based on a geophysical variable consisting of daily short- and long-wave radiation components calculated for any slope. The short-wave component is scaled to accommodate a simplified surface energy balance expression. Linear regression equations are derived for 10 and 50 cm soil temperatures by using this variable as a single determinant and based on a long term observation data set from a horizontal location. Extendability of these equations to sloped surfaces is tested by comparing the calculated data with the monthly mean soil temperature data observed in Iowa and at 12 locations near the Tennessee - Kentucky border with various slope and aspect factors. Calculated soil temperature variations agreed well with the observed data. Finally, this method is applied to a simulation study of daily mean soil temperatures over sloped corn fields on a 30 m by 30 m resolution. The outputs reveal potential effects of topography including shading by neighboring terrain as well as the slope and aspect of the land itself on the soil temperature.

  • PDF

Systematic Approach to The Extraction of Effective Region for Tongue Diagnosis (설진 유효 영역 추출의 시스템적 접근 방법)

  • Kim, Keun-Ho;Do, Jun-Hyeong;Ryu, Hyun-Hee;Kim, Jong-Yeol
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.45 no.6
    • /
    • pp.123-131
    • /
    • 2008
  • In Oriental medicine, the status of a tongue is the important indicator to diagnose the condition of one's health like the physiological and the clinicopathological changes of internal organs in a body. A tongue diagnosis is not only convenient but also non-invasive, and therefore widely used in Oriental medicine. However, the tongue diagnosis is affected by examination circumstances like a light source, patient's posture, and doctor's condition a lot. To develop an automatic tongue diagnosis system for an objective and standardized diagnosis, segmenting a tongue region from a facial image captured and classifying tongue coating are inevitable but difficult since the colors of a tongue, lips, and skin in a mouth are similar. The proposed method includes preprocessing, over-segmenting, detecting the edge with a local minimum over a shading area from the structure of a tongue, correcting local minima or detecting the edge with the greatest color difference, selecting one edge to correspond to a tongue shape, and smoothing edges, where preprocessing consists of down-sampling to reduce computation time, histogram equalization, and edge enhancement, which produces the region of a segmented tongue. Finally, the systematic procedure separated only a tongue region from a face image with a tongue, which was obtained from a digital tongue diagnosis system. Oriental medical doctors' evaluation for the results illustrated that the segmented region excluding a non-tongue region provides important information for the accurate diagnosis. The proposed method can be used for an objective and standardized diagnosis and for an u-Healthcare system.

Development of Fog Cooling Control System and Cooling Effect in Greenhouse (온실 포그 냉방 제어시스템 개발 및 냉방효과)

  • Park, Seok Ho;Moon, Jong Pil;Kim, Jin Koo;Kim, Seoung Hee
    • Journal of Bio-Environment Control
    • /
    • v.29 no.3
    • /
    • pp.265-276
    • /
    • 2020
  • This study was conducted to provide a basis for raising farm income by increasing the yield and extending the cultivation period by creating an environment where crops can be cultivated normally during high temperatures in summer. The maximum cooling load of the multi-span greenhouse with a floor area of 504 ㎡ was found to be 462,609 W, and keeping the greenhouse under 32℃ without shading the greenhouse at a high temperature, it was necessary to fog spray 471.6 L of water per hour. The automatic fog cooling control device was developed to effectively control the fog device, the flow fan, and the light blocking device constituting the fog cooling system. The fog cooling system showed that the temperature of the greenhouse could be lowered by 6℃ than the outside temperature. The relative humidity of the fog-cooled greenhouse was 40-80% during the day, about 20% higher than that of the control greenhouse, and this increase in relative humidity contributed to the growth of cucumbers. The relative humidity of the fog cooling greenhouse during the day was 40-80%, which was about 20% higher than that of the control greenhouse, and this increase in relative humidity contributed to the growth of cucumbers. The yield of cucumbers in the fog-cooled greenhouse was 1.8 times higher in the single-span greenhouse and two times higher in the multi-span greenhouse compared to the control greenhouse.