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A Study on the Heat and Moisture Transport Properties of Vapor-Permeable Waterproof Finished Fabrics for Sports Wear (스포츠웨어용 투습방수직물의 열·수분이동 특성에 관한 연구)

  • Son, Bu Hun;Kim, Jin-A;Kwon, Oh Kyung
    • Fashion & Textile Research Journal
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    • v.2 no.3
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    • pp.220-226
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    • 2000
  • This study was to determine the characteristics of vapor-permeable waterproof finished fabric by the coating method. 4 different kinds of coating fabrics (A : wet, porous, polyurethane, B : dry, no porous, polyurethane, C : shape memory polyurethane and D : dry, porous polyurethane) were used, which were developed recently With this sample, moisture transport rate ($40^{\circ}C$, 45%RH & $40^{\circ}C$, 95%RH), changes of coating side's shape by washing times, water repellency rate, contracted length, qmax, heat conductivity, heat keeping rate, heat keeping rate with cotton, heat keeping rate on humidity temperature and humidity within clothing etc. were checked. And it was done in a climate chamber under $20{\pm}2^{\circ}C$, $65{\pm}5%RH$. The results of this study were as follow; In the moisture vapor transmission of sample B and C increased on high temperature and high humidity while sample A and D decreased, on this condition. Qmax rate had high relation with ground fabric's surface properties and the order was A>C>D>B. Heat conductivity had high relation with thickness and surface properties. Heat keeping rates on sweat condition showed around half percents of heat keeping rates on normal condition, but had no relation with moisture vapor transport rate. Changes of the fabric's properties by washing times were different in accordance with the construction of fabrics and the coating resin. Sample C had tow heat keeping rate on the high temperature and humidity and high heat keeping rate on the low temperature and humidity Moisture transport rate of vapor-permeable waterproof finished fabrics had high relation with the properties of ground fabrics on low humidity condition, but on the high humidity condition, it was highly related with the properties of coating resin.

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Effects of Temperature and Salinity on Hatching Rate of Fertilized Egg in Fleshy Shrimp, Penaeus chinensis (대하(Penaeus chinensis) 수정난의 부화에 미치는 수온과 염분의 영향)

  • HUR Sung Bum;KIM Hyun Jun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.1
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    • pp.1-8
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    • 1996
  • The effects of temperature and salinity on hatching rate of fertilized egg were examined to develop the method for the efficient seed production in fleshy shrimp, Penaeus chinensis. At the temperature ranging from $20^{\circ}C\;to\;24^{\circ}C$, the hatching rate increased with temperature and the highest hatching rate $(95.5\%)$ occurred at $24^{\circ}C$. But, with the temperature above $26^{\circ}C$, the hatching rate decreased suddenly, and at $30^{\circ}C$, the egg did not hatch at all. The hatching rate increased with salinity within the range of $20\%_{\circ}\;to\;31\%_{\circ}$ and the highest hatching rate $(95.5\%)$ occurred at $31\%_{\circ}$. However, with the salinity above $31\%_{\circ}$, the rate decreased abruptly, and it was only $25.5\%\;at\;40\%_{\circ}$. The hatching speed of egg was the fastest at $24^{\circ}C$. The hatching rate at $24^{\circ}C$ with the salinity of $31\%_{\circ}\;was\;30.5\%$ within 18hrs of the hatching experiment and it attained to $95.5\%$ within 48hrs of the hatching experiment. At $24^{\circ}C$, the hatching rate with the salinity of $30\~31\%_{\circ}$ is 1,2 times higher than that of egg with the salinity of $33\~35\%_{\circ}$.

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Seed Germination of Gastrodia elata Using Symbiotic Fungi, Mycena osmundicola

  • Kim, Yong-Il;Chang, Kwang-Joon;Ka, Kang-Hyeon;Hur, Hyeon;Hong, In-Pyo;Shim, Jae-Ouk;Lee, Tae-Soo;Lee, Ji-Yul;Lee, Min-Woong
    • Mycobiology
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    • v.34 no.2
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    • pp.79-82
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    • 2006
  • The germination rate and longevity of seeds of Gastrodia elata Blume have been observed for 48 weeks using Mycena osmundicola strain H-21, one of fungi stimulating seed germination. Storage condition of post-harvest seeds was observed in the different temperature ranges of $-30^{\circ}C,\;-5^{\circ}C,\;5^{\circ}C\;and\;30^{\circ}C$ for 48 weeks. After storage period of 48 weeks, the germination rate of G elata was 65.7% at $5^{\circ}C$ and 71.6% at $-5^{\circ}C$, respectively. Although the germination rate of G. elata was 77.3% for 11 weeks at $25^{\circ}C$, the germination rate had been decreased gradually to 49.3% at 13 weeks, 0.3% at 23 weeks and then 0% at 25 weeks. The germination rate was reached to the level of 10% for 2 weeks at $-30^{\circ}C$ and then decreased to 0%.

Relationship between V/C and Accident Rate for Freeway Facility Sections (focused on Shingal-Ansan Freeway) (고속도로 시설물 구간의 교통혼잡도와 사고율의 관계 분석 (신갈-안산 고속도로를 중심으로))

  • Oh, Cheol;Chang, Jae-Nam;Chang, Myeong-Sun
    • Journal of Korean Society of Transportation
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    • v.17 no.2
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    • pp.21-27
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    • 1999
  • The objective of this study is to clarify the relationship between accident rate and V/C for freeway facility. The relationship can be used as a basic reference to predict and prevent traffic accident. The traffic volume and the number of accidents from 1992 to 1997 on Shingal-Ansan Freeway were analyzed in this study to clarify the relationship. Hourly accident rate and V/C were calculated for each facility sections : basic freeway section, tunnel section and toll gate section. The accident rate models consisting of an independent variable of V/C were established by repression analysis and compared with each other. The relationship between accident rates and V/C ratios represented U-shaped pattern for all sections. The result of this study indicates that accident rates are highest in the low hourly V/C range, decrease with increasing V/C ratio, and then increase as the V/C ratio increases. The accident rate of toll gate section is in general higher than that of other sections. Although the accident rate of tunnel section is higher than that of basic freeway section when V/C is above 0.67, there is no significant difference of accident rate between basic freeway and tunnel section when V/C is between 0.5 and 0.8. Basic freeway tunnel and toll gate section have the minimum accident rate when V/C is 0.78, 0.75 and 0.57 respectively.

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Survival Rate and Growth of Palaemon gravieri Larvae Reared in the Laboratory (Decapoda: Caridea: Palaemonidae)

  • Kim, Sung-Han
    • Fisheries and Aquatic Sciences
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    • v.8 no.2
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    • pp.90-96
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    • 2005
  • The larvae of Palaemon gravieri were reared in the laboratory at three different temperature regimes ($15^{\circ}C,\;20^{\circ}C,\;and\;25^{\circ}C$) with the salinity ranges (28-32 psu) to understand how temperature and body size influence survival rate, and growth components (molt increment and intermolt period). The optimum temperature for the highest survival rate was $25^{\circ}C$. The intermolt periods consistently increased with an increase in size and instar number; however, the molt increments at successive instars generally decreased with an increase in size and instar number. The shortest intermolt period and the highest larval growth rate both occurred at $25^{\circ}C$. Thus, the optimum temperature for larval survival and growth rate was found to be $25^{\circ}C$ which was the temperature at which the larvae actually appear in nature.

Effects of Cryoprotectants and Freezing Rates on Cryopreservation of Sea Urchin, Anthocidaris crassispina Sperm

  • Kang, Kyoung-Ho;Kho, Kang-Hee;Kim, YoungHun
    • Journal of Aquaculture
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    • v.17 no.1
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    • pp.46-50
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    • 2004
  • In the present study, attempts were made to cryopreserve sea urchin, Anthocidaris crassispina sperm in liquid nitrogen, to evaluate the effects of various cryoprotectants and freezing rates on motility, survival rate and fertilization rate of the post-thawing sperm, and the ultrastructural changes of sperm after cryopreservation were observed. The highest values of sperm motility (motility index: 3.3$\pm$0.37) and survival rate (72$\pm$3.5%) were obtained with 15% dimethyl sulfoxide (DMSO), and these values were significantly higher than those of sperm preserved with glycerol. Comparisons of motilities and survival rates between treatments of difference freezing rates showed that there was no difference between procedures (a) 5$0^{\circ}C$/min to -8$0^{\circ}C$ (motility index: 3.3$\pm$0.31 ; survival late 70$\pm$2.7%) and (b) 3$0^{\circ}C$/min to -8$0^{\circ}C$ (motility index: 3.1$\pm$0.29; survival rate 69$\pm$3.7%), while the results of (c) 1$0^{\circ}C$/min to -8$0^{\circ}C$ were significantly lower than the others (motility index: 2.2$\pm$0.33 ; survival rate 42$\pm$4.6%). There was no significant difference in fertilization rate between fresh sperm and sperm preserved with 15% DMSO as cryoprotectant and freezing rate (3$0^{\circ}C$/min to -8$0^{\circ}C$). Some ultrastructural changes of sperm, such as the detachment of plasma membrane, the destruction of mitochondria, and the flagellum rolling up head, were observed after cryopreservation. Morphological normality of the sperm in 15% DMSO frozen at the ratio of 5$0^{\circ}C$/min to -8$0^{\circ}C$ was better than the others.

Germination Responses of Cassia mimosoides var nomame Seeds to Temperature (온도에 대한 차풀(Cassia mimosoides var nomame)종자의 발아 반응)

  • Lee, Ho-Joon;Ji-Seok Suh;Young-Jin Yoon;Ung-Kyu Lim
    • The Korean Journal of Ecology
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    • v.19 no.3
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    • pp.231-240
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    • 1996
  • The germination responses of Cassia mimosoides var. nomame seeds to temperature were examined under various conditions. The temperature range allowing germination was $20~40^{\circ}C$, and the linear relationship between the germination rate and temperature appeared to exist between $28~38^{\circ}C$ The total thermal time required for germination (10~80%) of C. mimosoides seeds ranged from 259 Kh (degree Kelvin$\times$hours) to 421 Kh and base temperature range was relatively constant, i.e., $23.39~26.68^{\circ}C$. In the increasing temperature (IT) regime, C. mimosoides seeds started to germinate at $16^{\circ}C$ and showed greater germination rate with increasing temperatures. The final germination rate was 64% at $36^{\circ}C$. On the other hand, in the decreasing temperature (DT) regime, the seeds began to germinate at $36^{\circ}C$, and the final germination rate was 52% at $20^{\circ}C$. An induced dormancy occurred at $16^{\circ}C$ in the DT regime.

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Crystal Growth of 3C-SiC Using HMDS Gas Source (HMDS 가스원을 이용한 3C-SiC의 결정성장)

  • Sun, Ju-Hun;Chung, Yun-Sik;Chung, Gwiy-Sang;Nishino, Shigehiro
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.735-738
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    • 2002
  • Single crystal 3C-SiC(cubic silicon carbide) thin-films were deposited on Si(100) substrate up to a thickness of $4.3{\mu}m$ by APCVD method using HMDS(hexamethyildisilane) at $1350^{\circ}C$. The HMDS flow rate was 0.5 sccm and the carrier gas flow rate was 2.5 slm. The HMDS flow rate was important to get a mirror-like crystal surface. The growth rate of the 3C-SiC films was $4.3{\mu}m/hr$. The 3C-SiC epitaxical films grown on Si(100) were characterized by XRD, AFM, RHEED, XPS and raman scattering, respectively. The 3C-SiC distinct phonons of TO(transverse optical) near $796cm^{-1}$ and LO(longitudinal optical) near $974{\pm}1cm^{-1}$ were recorded by raman scattering measurement. The heteroepitaxially grown films were identified as the single crystal 3C-SiC phase by XRD spectra$(2{\theta}=41.5^{\circ})$.

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Physical Characteristics of 3C-SiC Thin-films Grown on Si(100) Wafer (Si(100) 기판 위에 성장돈 3C-SiC 박막의 물리적 특성)

  • ;;Shigehiro Nishino
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.11
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    • pp.953-957
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    • 2002
  • Single crystal 3C-SiC (cubic silicon carbide) thin-films were deposited on Si(100) wafer up to the thickness of 4.3 ${\mu}{\textrm}{m}$ by APCVD (atmospheric pressure chemical vapor deposition) method using HMDS (hexamethyildisilane; {CH$_{3}$$_{6}$ Si$_{2}$) at 135$0^{\circ}C$. The HMDS flow rate was 0.5 sccm and the carrier gas flow rate was 2.5 slm. The HMDS flow rate was important to get a mirror-like crystal surface. The growth rate of the 3C-SiC film was 4.3 ${\mu}{\textrm}{m}$/hr. The 3C-SiC epitaxial film grown on Si(100) wafer was characterized by XRD (X-ray diffraction), AFM (atomic force microscopy), RHEED (reflection high energy electron diffraction), XPS (X-ray photoelecron spectroscopy), and Raman scattering, respectively. Two distinct phonon modes of TO (transverse optical) near 796 $cm^{-1}$ / and LO (longitudinal optical) near 974$\pm$1 $cm^{-1}$ / of 3C-SiC were observed by Raman scattering measurement. The heteroepitaxially grown film was identified as the single crystal 3C-SiC phase by XRD spectra (2$\theta$=41.5。).).

Characterization of 3C-SiC grown on Si(100) water (Si(100) 기판상에 성장된 3C-SiC의 특성)

  • Na, Kyung-Il;Chung, Yun-Sik;Ryu, Ji-Goo;Chung, Gwiy-Sang
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.533-536
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    • 2001
  • Single crystal cubic silicon carbide(3C-SiC) thin film were deposited on Si(100) substrate up to a thickness of $4.3{\mu}m$ by APCVD(atmospheric pressure chemical vapor deposition) method using hexamethyildisilane(HMDS) at $1350^{\circ}C$. The HMDS flow rate was 0.5 sccm and the carrier gas flow rate was 2.5 slm. The HMDS flow rate was important to get a mirror-like. The growth rate of the 3C-SiC films was $4.3{\mu}m/hr$. The 3C-SiC epitaxical layers on Si(100) were characterized by XRD(X-ray diffraction), raman scattering and RHEED(reflection high-energy electron diffraction), respectively. The 3C-SiC distinct phonons of TO(transverse optical) near $796cm^{-1}$ and LO(longitudinal optical) near $974{\pm}1cm^{-1}$ were recorded by raman scattering measurement. The deposition films were identified as the single crystal 3C-SiC phase by XRD spectra($2{\theta}=41.5^{\circ}$). Also, with increase of films thickness, RHEED patterns gradually changed from a spot pattern to a streak pattern.

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