• Title/Summary/Keyword: energy space

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An Experimental Study on the Operating Characteristics with HVAC Type of Shopping Center in Underground Passage (지하도상가의 HVAC 구성방식에 따른 운전특성 연구)

  • Lee, Hong-Cheol;Hwang, In-Ju
    • Proceedings of the SAREK Conference
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    • 2007.11a
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    • pp.76-81
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    • 2007
  • The shopping center in underground passage increased for efficient space utilization in urban area. This study describes operation characteristics of all air type and hybrid type with local ventilation and fan coil unit fixed to ceiling. In order to compare energy saving, thermal environment and installation space, etc., integrated simulator with heat production and indoor distribution system is designed and constructed. Energy saving of the hybrid system is calculated as over 30% compared to conventional all air type. And also the results showed that humidity decreased about 6%, also indoor thermal distribution is improved as temperature variation of around $1^{\circ}C$.

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Observational determination of the electron flux boundary conditions of the radiation belt as a function of solar wind condition

  • Lee, Dae-Young;Shin, Dae-Kyu
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.134.1-134.1
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    • 2012
  • The radiation belt structure can be approximately reproduced by a form of diffusion equation, which takes into account the radial diffusion process as well as those in pitch angle and energy. The solution of the equation depends on several factors including initial and boundary conditions, diffusion coefficients, and plasmapause location. In this paper, we have attempted to determine a set of approximate functions for the energetic electron fluxes near the outer edge of the outer belt in terms of solar wind variable. We used the electron flux data from SST onboard the THEMIS spacecraft and determined its correlation with solar wind conditions in a systematic way. The functions were determined separately for different energy channels from ~30 keV up to 719 keV. Our determination of these functions allows us to predict the radial boundary condition for the electron flux, which can be implemented in a forecast model.

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A Study on the Wiring Plan Considering Construction and Frame Performance Degradation of BIPV System (BIPV시스템 시공 및 프레임 성능저하를 고려한 배선처리방안 제시에 관한 연구)

  • Oh, Min-Seok;Kim, Gi-Cheol
    • Journal of the Korean Solar Energy Society
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    • v.38 no.4
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    • pp.33-42
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    • 2018
  • In the application of the BIPV system, it is expected that the workability is lowered due to the difficulty in securing the space for wiring in the frame and the performance of the frame due to the wiring hole processing is lowered. Therefore, In this study, we propose a method to improve the wiring of the inner space of the BIPV frame, and through the simulation evaluation process, the thermal and condensation performance are secured by complementing the problems caused by the hole machining, and the time and effort required for BIPV construction are reduced. For this purpose, a wiring treatment method using a flange insertion tube was proposed, and the thermal and condensation performance was evaluated through simulation analysis.

A Study on the TCAD Simulation to Predict the Latchup Immunity of High Energy Ion Implanted CMOS Twin Well Structures (고 에너지 이온 주입된 CMOS 쌍 우물 구조의 레치업 면역성 예측을 위한 TCAD 모의실험 연구)

  • 송한정;김종민;곽계달
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.2
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    • pp.106-113
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    • 2000
  • This study describes how a properly calibrated simulation method could be used to investigate the latchup immunity characteristics among the various high energy ion implanted CMOS twin well (retro-grade/BILLI/BL) structures. To obtain the accurate quantitative simulation analysis of retrograde well, a global tuning procedure and a set of grid specifications for simulation accuracy and computational efficiency are carried out. The latchup characteristics of BILLI and BL structures are well predicted by applying a calibrated simulation method for retrograde well. By exploring the potential contour, current flow lines, and electron/hole current densities at the holding condition, we have observed that the holding voltage of BL structure is more sensitive to the well design rule (p+to well edge space /n +to well edge space) than to the retrograde well itself.

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A Study on GIS Data Extraction Using Simulated ROCSAT-2 Image

  • Chang, Chih-Li;Wu, Chi-Nan;Hsu, Wei-Chen;Hsiao, Kuo-Hsing;Liao, Tzu-Yi;Chern, Jeng-Shing
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.591-593
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    • 2003
  • The study demonstrates the data extraction capabilities from the simulated ROCSAT-2 image by manual delineation. The GIS data are able to identify as fifteen categories of the classes I & II for the simulated ROCSAT-2 and SPOT image data. The areas of the paddy are identified almost the same results for both cases, but the arid farmland are identified differently about 30%. The ROCSAT-2 case can be also identified as seven more categories of the class III, but SPOT-4 case cannot.

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The Study on BEAM for the Space Domain Analysis of EEG

  • Lee, Gun-Ki;Kang, Ik-Tae;Shin, Sang-Jin
    • Journal of Biomedical Engineering Research
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    • v.15 no.2
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    • pp.129-134
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    • 1994
  • In this paper, computerized BEAM was implemented for the space domain analysis of EEG. Transformation from temporal summation to two-dimensional mappings is formed by 4 nearest point interpolaton method. Methods of representation of BEAM are two. One is dot density method which classify brain electrical potential 9 levels by dot density of gray levels and the other is colour method which classify brain electrical 12 levels by red-green colours. In this BEAM, instantaneous change and average energy distribution over any arbitrary time interval of brain electrical activity could be observed and analyzed easily. In the frequency domain, the distribution of energy spectrum of a special band can easily be distinguished normality and abnormality.

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FAR-INFRARED SPECTRAL ENERGY DISTRIBUTION OF THE PULSAR WIND NEBULA 3C 58

  • Park, Jaeguen;An, Hongjun
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.48.3-48.3
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    • 2019
  • We present analysis results of far infrared (IR) data for 3C 58. We use Herschel observations to measure the IR spectral slope of the source. Our measurements add new IR data points to exisiting high-frequency ones and allow us to improve the IR spectral energy distribution (SED) of 3C 58, and so a cooling break expected in the optical band can be located more precisely. We interpret the SED and the break using a synchrotron+ inverse-Compton model for PWNe and infer flow properties in 3C 58. Because the IR data are contaminated by foregrounds and backgrounds, we discuss impacts of the contamination on our conclusion.

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Heat Transfer Coefficients of Concentric Annuli for Testing Heat Transfer Characteristics of Alternative Refrigerants in Tubes (대체냉매 관내 열전달특성 시험을 위한 동심이중원관의 환상유로의 열전달계수)

  • KIM, MAN-HOE
    • Journal of Hydrogen and New Energy
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    • v.32 no.1
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    • pp.63-67
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    • 2021
  • Accurate measurements of the heat transfer coefficients of concentric annular space for the test section is important to measure the tube-side heat transfer coefficients of working fluids. This paper presents the annular side heat transfer coefficients of concentric annuli with variation of tube diameter ratios using Wilson plot method. The test facility has a straight, horizontal test section with an active length of 3.0 m. Inner/outer diameters of test tubes are 7.0/7.5 and 8.0/8.56 mm, respectively. An outer diameter of annulus side is 16.0 mm. The test results show that convective heat transfer coefficients in annuli increase with annular diameter ratio. The correlations for convective heat transfer coefficients in annuli are also developed.

A Study on the Catalytic Ortho-Para Hydrogen Conversion in the Cryogenic Heat Exchanger Filled with Catalysts for Hydrogen Liquefaction (수소액화용 극저온 열교환기 내 촉매 수소 전환반응에 관한 연구)

  • SOHN, SANGHO;YOON, SEOK HO
    • Journal of Hydrogen and New Energy
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    • v.32 no.3
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    • pp.180-188
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    • 2021
  • This paper conducted a study on the ortho-para hydrogen conversion in the cryogenic heat exchanger filled with catalysts for hydrogen liquefaction by utilizing the numerical model of plate-fin heat exchanger considering catalytic reaction of ortho-para hydrogen conversion, heat and mass transfer phenomena and fluid dynamics in a porous medium. Various numerical analyzes were performed to investigate the characteristics of ortho-para hydrogen conversion, the effects of space velocity and activated catalyst performance.

Energy Load according to the Units of Apartment House (공동주택 세대 위치에 따른 에너지 부하량)

  • Kim, Sung-Hoon;Lee, Jun-Gi;Kim, Yong-Tae;Lee, Kyung-Hee
    • Journal of Power System Engineering
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    • v.19 no.2
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    • pp.78-83
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    • 2015
  • In Korea, multi-housing in one of the most common types of residential space due to its easy management and convenience. In particular, south-facing plate-type(一) multi-housing has attracted a great deal of public interest because it consumes less energy compared with other types of multi-housing, making it advantageous from an energy-saving perspective. Although there have been many studies on the annual energy consumption of multi-housing in relation to building shape and area of window, there have not been sufficient research on the annual energy consumption of multi-housing in relation to individual units of the multi-housing. The purpose of this study is to propose a strategy for reducing energy consumption in plate-type(一) multi-housing, taking the units with the lowest energy consumption as the standard. The result, Standard Models's energy load was as 4000 ~ 5600kWh, and Passive Houses's energy load was less than Stand Models at the 1600kWh.