• Title/Summary/Keyword: Emissivity

Search Result 302, Processing Time 0.022 seconds

Effect of Far-Infrared Finishing on Brassiere Pad

  • Shin Jung-Sook
    • The International Journal of Costume Culture
    • /
    • v.8 no.2
    • /
    • pp.124-131
    • /
    • 2005
  • This study focused on the change of skin temperature by the emissivity and emission power of far-infrared for conformant far infrared effect to naked eyes. The study method is to manufacture the bra pad by each concentration on far-infrared materials of illite powder $(K,H_3O)AI_2(Si,Al)_4O_{10}(H_2O,OH)_2)$, liquid alumina ($Al_2O_3$), the extracted liquid from 29 kind of medical plants, then, measured change of skin temperature. Result are as follows. Far-infrared were emitted each $90.2\%,\;90.1\%,\;89.7\%$ from the illite powder, liquid alumina, extracted liquid from medical plants. When the testee weared the bra pad, the temperature of coated bra pad was $0.5^{\circ}C$ higher than the non finished bra pad. Washing fastness on far-infrared finishing was better dope addition method than coating method.

  • PDF

Infrared Image Simulation for Estimating the Effectiveness of Camouflage Measures (표적은폐도구의 유용도 평가를 위한 적외선화상 모사)

  • Jung, Jinsoo;Kauh, S. Ken;Yoo, Hoseon
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.23 no.8
    • /
    • pp.1010-1021
    • /
    • 1999
  • Camouflage measures in military purpose utilize the apparent temperature difference between target and background, so it is essential to develop a thermal analysis program for apparent temperature predictions and to apply some camouflage measures to real military targets for camouflage purpose. In this study, a thermal analysis program including conduction, convection and radiation is developed and the validity of radiation heat transfer terms is examined. The results show that longwave radiation along with solar radiation should be included in order to predict the apparent temperature as well as the physical temperature precisely. Longwave emissivity variation as an effective camouflage measures is applied to a real M2 tank. From the simulation results, it is found that an effective surface treatment, such as painting of a less emissive material or camouflage clothing, may provide a temperature similarity or a spatial similarity, resulting in an effective camouflage.

A Study of Adiabatic Performance for Vacuum Glazing with Design Conditions (진공유리의 설계 조건에 따른 단열 성능 연구)

  • Hwang, Il-Sun;Lee, Young-Lim
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.21 no.4
    • /
    • pp.582-587
    • /
    • 2012
  • Recently, the low-emissivity glass has been used to reduce the energy loss through building windows. However, it simply reduces the inflow of solar rays and has a relatively high heat transmission coefficient. To solve the problems, a high-efficiency vacuum glazing has been under development but it has not been actively used due to its high price and insufficient performance. In this paper, the effects of internal pressure, pillar (spacer) height, pillar diameter, pillar interval, emissivity etc. on the performance of vacuum glazing have been analyzed with three-dimensional computational fluid dynamics and structural analysis. As a result, the performance of vacuum glazing was predicted more accurately and major factors that determine the performance of vacuum glazing were optimized.

Dyeing of Cotton Knitting Fabrics with An inorganic substance -Centering around Loess and Mud- (무기물을 이용한 면 편성물 염색성 -황토, 머드를 중심으로-)

  • 신인수;유복선;선우권
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.26 no.10
    • /
    • pp.1436-1442
    • /
    • 2002
  • In this paper, the effect of the loess and mud of an inorganic substance dyed on cotton knitting fabrics have been studied The structure and chemical composition of loess and mud was analyzed. And the Far-Infrared emissivity and emission power, colorfastness, anti-bacterial properties cotton knitting fabrics dyed with loess and mud were also evaluated. The structure and chemical composion of loess and mud was almost identical structure and to be alike main components were SiO$_2$, Al$_2$0$_3$ and Fe$_2$O$_3$. The cotton hitting fabrics dyed with loess and mud have good colorfastness and anti-bacterial properties. when the dyed fabrics was after-treated with diphenyl ether, the anti-bacterial property were improved. Far-Infrared emissivity and emission power cotton knitting fabrics dyed with loess and mud have very good.

Unsteady Heat Transfer in Radiatively Active Spherical Medium (구형 복사 매질에서의 비정상 열전달 특성에 관한 연구)

  • 한상헌;백승욱;안국영
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.17 no.10
    • /
    • pp.2582-2589
    • /
    • 1993
  • Transient heat transfer characteristics of cooling of a spherical body were investigated in the radiatively active spherical medium. Initially the spherical body and the medium were maintained at their constant temperatures. Then heat transfer begins from spherical body t medium. The heat transfer mode inside the spherical body is just conduction. But heat is transferred by both conduction and radiation inside the medium. All thermodynamic properties were held constant in time. Spherical symmetry is assumed. DOM was adopted to solve RTE. The effect of characteries-tic optical thickness, conduction to radiation parameters, and solid surface emissivity has been studied.

A Fundamental Physical Properties of Wood with Charcoal and Loess (목탄과 황토함유 목질소재의 기초물성)

  • Lee, Wun-Hee
    • Journal of the Korea Furniture Society
    • /
    • v.17 no.2
    • /
    • pp.49-56
    • /
    • 2006
  • This research was carried out to examine the FIR (far-infrared rays) emissivity and emission power of five types of flooring board by the mixing ratio of charcoal and loess, and the physical property of five types of injected flooring board by the amount of mixture. Type D was appeared the most high value of FIR emissivity and emission power. But there was a little difference among the five types of flooring board values. In physical properties, control type flooring board and injected flooring board showed a similar tendency. Among the domestic trees, all of hard wood seems to be used to surface wood for strong hardness flooring board. But a coniferous tree was not.

  • PDF

Analysis of absorption and scattering characteristics of alumina particles using Mie theory (Mie Theory를 이용한 알루미나 입자의 흡수 및 산란 특성 분석)

  • Ko, Ju-Yong;Kim, In-Sun
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2011.11a
    • /
    • pp.962-967
    • /
    • 2011
  • Radiative properties of alumina particles which is the main element of the plume from booster and kick motor used for increasing thrust and insertion into the orbit is analyzed. In order to derive the wavelength integrated (i.e., gray) emissivity, emission term in radiative transfer equation is rearranged to be able to tie up with the parameters induced from fundamental particle scattering Mie theory. Result shows that derived gray emissivity with optical properties increases with temperature rising.

  • PDF

THE MODIFIED BRIGHTNESS TEMPERATURE DIFFERENCE FOR AEROSOL DETECTION

  • Kim, Jae-Hwan;Ha, Jong-Sung;Lee, Hyun-Jin
    • Proceedings of the KSRS Conference
    • /
    • v.2
    • /
    • pp.794-796
    • /
    • 2006
  • This study investigated the Brightness Temperature Difference threshold as criterion between aerosols and clouds in conjunction with radiative transfer model. Surface temperature is caused by a significant error over 50% in the BTD threshold. In addition, The BTD threshold contains the uncertainties about 20% due to the surface emissivity and 8% due to the satellite zenith angle. Therefore, we have composed the Look-up table for BTD between 11㎛and 12㎛ according to satellite zenith angle, surface temperature, and surface emissivity. The modified BTD show the enhanced signal, especially over bright surface such as desert in China. However, a weak aerosol signal over Ocean remains in the modified BTD.

  • PDF

Infrared Spectroscopic Investigation of Lubricants under Shear (적외선 스펙트럼 측정방식을 이용한 윤활유의 변화연구)

  • 안영재
    • Tribology and Lubricants
    • /
    • v.3 no.2
    • /
    • pp.44-49
    • /
    • 1987
  • Molecular alignment has been postulated as influencing non-Newtonian behavior of liquid lubricants containing various additives. Four blended lubricants, two synthetic and two mineral were analyzed by FTIR spectroscopy. All of the lubricants exhibited polarization changes in their infrared emission spectra at 60$\circ$C under shear. For this work a special mockup journal bearing was constructed to seperate load and shear effects. At a temperature of 100$\circ$C polarization by shear was always reduced, presumably by Browninn motion. This work should be useful in pointing to the shear-sensitive factors. The presence of of a VI improving additive is manifested by the independence of the infrared emissivity with temperature at several wavelengths; a lubricant without a VI improver generally shows a decrease of emissivity at higher temperature.

Effect of Ag Formation Mechanism on the Change of Optical Properties of SiInZnO/Ag/SiInZnO Multilayer Thin Films (SiInZnO/Ag/SiInZnO 다층박막의 Ag 형성 메카니즘에 따른 광학적 특성 변화)

  • Lee, Young Seon;Lee, Sang Yeol
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.26 no.5
    • /
    • pp.347-350
    • /
    • 2013
  • By inserting a very thin metal layer of Ag between two outer oxide layers of amorphous silicon indium zinc oxide (SIZO), we fabricated a highly transparent SIZO/Ag/SIZO multilayer on a glass substrate. In order to find the optimized thickness of Ag layers, we investigated the variation of optical properties depending on Ag thickness. It was found that the transition of Ag layer from island formation to a continuous film occurred at a critical thickness. Continuity of the Ag film is very important for optical properties in SIZO/Ag/SIZO multilayer. With about 15 nm thick Ag layer, the multilayer showed a high optical transmittance of 80% at 550 nm and low emissivity in IR.