• 제목/요약/키워드: C rate

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

  • 손부현;김진아;권오경
    • 한국의류산업학회지
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    • 제2권3호
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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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대하(Penaeus chinensis) 수정난의 부화에 미치는 수온과 염분의 영향 (Effects of Temperature and Salinity on Hatching Rate of Fertilized Egg in Fleshy Shrimp, Penaeus chinensis)

  • 허성범;김현준
    • 한국수산과학회지
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    • 제29권1호
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    • pp.1-8
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    • 1996
  • 본 실험은 대하의 효율적인 종묘생산을 위하여 수온과 염분에 따른 수정난의 부화율에 관한 실험으로서 다음과 같은 결과를 얻었다. 대하수정난의 부화에 미치는 수온의 영향을 조사한 결과, $24^{\circ}C$에서 $95.5\%$의 가장 높은 부화율을 보였다. $20^{\circ}C$에서 $24^{\circ}C$까지는 수온이 올라갈수록 부화율은 높게 나타났으며, $26^{\circ}C$이상부터는 수온이 올라갈수록 부화율은 급격히 낮아져, $30^{\circ}C$에서는 전혀 부화가 되지 않았다. 염분의 영향을 조사한 결과, $31\%_{\circ}$에서 $95.5\%$의 가장 높은 부화율을 보였다. $20\%_{\circ}$, 부터 $31\%_{\circ}$까지는 염분이 상승할수록 부화율은 증가하였고, $33\%_{\circ}$, 부터는 염분이 상승할수록 부화율은 낮아져 $40\%_{\circ}$, 에서는 $25.5\%$%로 급격히 감소하였다. 수온 $24^{\circ}C$에서의 부화속도는 다른 수온구에서보다 가장 빨랐고 특히 염분 $31\%_{\circ}$의 실험구에서는 18시간 만에 $30.5\%$, 48시간만에 $95.5\%$가 부화되어 가장 빠른 부화속도를 보였다. 대하수정난의 부화를 위한 최적 수온은 비교적 협온성이라고 할수있다. 또 최적수온인 $24^{\circ}C$에서도 자연해수의 염분구 $(33\~35\%_{\circ})$보다 다소 낮은 $30\~31\%_{\circ}$,에서는 약 $20\%$정도 더 높은 부화율이 유도되었다. 이러한 결과를 볼 때 대하수정난 부화를 위한 최적염분 역시 협염성이며 특히 수온이 높을 때 염분이 부화율에 미치는 영향은 매우 민감하였다.

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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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    • 제34권2호
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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%.

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

  • 오철;장재남;장명순
    • 대한교통학회지
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    • 제17권2호
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    • pp.21-27
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    • 1999
  • 고속도로 시설물 구간의 교통혼잡도(V/C)와 사고율의 관계를 분석하는 것이 본 연구의 목적이다. 본 연구에서 분석된 사고율과 V/C의 관계는 교통사고의 예측과 예방을 위한 기초 자료로 유용하게 쓰일 수 있을 것으로 판단된다. 본 연구에서는 신갈-안산간 고속도로의 개통시(92년)부터 97년까지의 교통량과 사고 자료를 이용하였으며, 시간당 사고율과 V/C를 계산하여 기본구간, 터널구간, 영업소구간의 V/C와 사고율(AR)을 비교·분석하였다. V/C와 사고율의 관계는 모든 구간에서 "U"형의 곡선 형태를 나타냈다. 분석 결과를 보면 V/C가 낮을 때 사고율이 가장 높았으며 V/C가 증가함에 따라 사고율이 감소하다가 일정수준 이상에서는 다시 사고율이 증가하는 것으로 나타났다. 영업소구간의 사고율이 V/C의 전 범위에 걸쳐 기본구간이나 터널구간보다 높게 나타났다. 터널구간의 경우 기본구간과 비교 시 V/C=0.67을 기준으로 그 이하에서는 기본구간이, 그 이상에서는 터널구간이 기본구간보다 사고율이 높은 것으로 분석되었다. V/C가 0.5∼0.8 구간에서는 기본구간과 터널구간의 사고 율이 큰 차이가 없는 것으로 나타났다. 기본구간 터널구간 영업소구간의 V/C가 각각 0.78, 0.75, 0.57일 때 사고율이 가장 낮은 것으로 나타났다.

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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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    • 제8권2호
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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
    • 한국양식학회지
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    • 제17권1호
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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.

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

  • Lee, Ho-Joon;Ji-Seok Suh;Young-Jin Yoon;Ung-Kyu Lim
    • The Korean Journal of Ecology
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    • 제19권3호
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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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HMDS 가스원을 이용한 3C-SiC의 결정성장 (Crystal Growth of 3C-SiC Using HMDS Gas Source)

  • 선주헌;정연식;정귀상
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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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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Si(100) 기판 위에 성장돈 3C-SiC 박막의 물리적 특성 (Physical Characteristics of 3C-SiC Thin-films Grown on Si(100) Wafer)

  • 정귀상;정연식
    • 한국전기전자재료학회논문지
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    • 제15권11호
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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。).).

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

  • 나경일;정연식;류지구;정귀상
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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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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