• Title/Summary/Keyword: Clear Day

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Characteristics of the Erythemal Ultraviolet-B (EUV-B) Irradiance in Anmyeon (Korea Global Atmosphere Watch Center)

  • Hong, Gi-Man;Park, Jeong-Gyoo
    • Journal of Korean Society for Atmospheric Environment
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    • v.24 no.E2
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    • pp.74-82
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    • 2008
  • We have examined seasonal and annual means of clear-sky solar noon and daily erythemal ultraviolet-B irradiances measured in Anmyeon. The intensity of the EUV-B irradiance is mainly dependent on solar zenith angle (SZA) and total ozone amounts on clear day conditions. The daily maximum occurs near solar noon time and the highest monthly accumulated EUV-B is seen in July in Anmyeon. The maximum daily variation occurs in June and July due to precipitation and clouds. The 7-year trend of EUV-B irradiance shows that it is slightly increasing. Additionally, we could confirm that aerosol effects such as Asian Dust decreases the EUV-B irradiance reaching the ground surface by 35% to 60%. For more than 45% of the summer days, EUV-B irradiacne was high enough that the UV index registered higher than category Extremely High. This information will be very important for evaluation of the UV index for prevention of both skin cancer and ecosystem damages as well as to understand UV climatology over the Korean Peninsula.

A Study on the Analysis of Solar Radiation Characteristics on a High Elevated Area (고지대 일사량 특성분석에 관한 연구)

  • Jo, Dok-Ki;Kang, Young-Heack;Auh, Chung-Moo
    • Journal of the Korean Solar Energy Society
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    • v.23 no.3
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    • pp.23-28
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    • 2003
  • The purpose of this study is to procure basic data to be used for solar power plant and concentrating collector designs. Site elevation is one of the major factors which influences the incoming insolation to the earth surface. Because the nonpermanent gases such as ozone, water vapor are unmixed components of the atmosphere and their concentrations are the function of height, the site elevation effects the relative proportion of the atmospheric constituents. We have measured solar radiation on Jiri Mt. (1,400m) and in Gurye area(115m) at the near same latitude. These values were then compared to obtain their characteristics and to investigate the potential for the solar utilization for both high and low elevated areas. From the experimental results, we concluded that 1) Daily mean horizontal global radiation and normal beam radiation on Mt. Jiri are 9.5%, and 35.3% higher than Gurye area respectively for a clear day. 2) A significant difference in atmospheric clearness index is observed between Mt. Jiri and Gurye areas.

Aerosol Optical and Spectral Characteristics in Yellow Sand Events on April, 1998 in Seoul. Part I: Observation (분광복사계와 일사계 관측에 의한 황사 및 에어러솔의 광학적 특성 연구)

  • Hye-Sook Park;Hyo-Sang Chung;Gyun-Myeong Bag;Hong-Ju Yoon
    • Korean Journal of Remote Sensing
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    • v.14 no.3
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    • pp.307-314
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    • 1998
  • To examine the detectability of the yellow sand and/or aerosol from China crossing over the Yellow Sea within the range of OSMI wavelengths(400-900 nm), we have investigated the optical characteristics of aerosols in yellow sand events observed on April, 1998 in Seoul. The spectral reflectance(%) and aerosol optical thickness in the range of Visible(VIS) and near Infrared (NIR) wavelengths were derived from the measurements of solar radiation using the GER-2600 spectroradiometer and sunphotometer during the April, 1798. The average spectral reflectance for the yellow sand events is over 40% and higher around 14:30 than 12:00 LST, but that for clear days is about 20% both at 12:00 and 14:30 LST in the range of 500-900 nm. The aerosol optical thickness at 501 nm varied from 0.25 on very clear day to 1.01 during a so-called "yellow-sand" episode and that for 673 nm varied from 0.14 to 0.92, respectively.

An Experimental Study on the Thermal Performance of the Flat Roof in Proportion to Directional Changes (평지붕의 방위별 열성능에 관한 실험적 연구)

  • 박병규;황하진;이경희
    • Journal of the Korean housing association
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    • v.12 no.2
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    • pp.191-198
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    • 2001
  • The aim of this research was to examine the thermal performance of the flat roof in proportion to various directional changes, the results of which were drawn from the miniature model experiment. In this process, various thermal environmental factors were measured and compared with one another to research their aspects of changes. The brief results of this research are as follows: 1) The indoor temperature and load per hour in proportion to directional changes shows the same degree of changes. As for the results of the clear-sky and cloudy-sky experiments, both of them generally appear advantageous in the order of S, $S-30^{\cire}C$-E, $S-30^{\cire}C$-W, $S-60^{\cire}C$-W, E, $S-60^{\cire}C$-E, despite slight differences in the indoor temperature and load per hour in proportion to directional changes. 2) As for the total load of degree day per direction of the clear-sky and cloudy-sky experiments, both of them shows their advantageous results in the order of S, $S-30^{\cire}C$-E, $S-30^{\cire}C$-W, $S-60^{\cire}C$-W, E, $S-60^{\cire}C$-E, despite minor differences in their loads. 3) As for the peak load of degree hour, while the clear-sky experiment shows its advantage in the order of $S-30^{\cire}C$-E, S, $-30^{\cire}C$-W, $S-60^{\cire}C$-W, E, $S-60^{\cire}C$-E, the cloudy-sky experiment does so in the order of S, $S-30^{\cire}C$-E, $S-30^{\cire}C$-W, E, $S-60^{\cire}C$-W, $S-60^{\cire}C$-E.

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Analysis of Solar Irradiance Measurement From a Multi-Filter Radiometer At Kwangju, South Korea.

  • Ogunjobi, K.O.;Kim, Y.J.;He, Z.;Ryu, S.Y.
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2001.11a
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    • pp.335-335
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    • 2001
  • Direct-normal, total horizontal and diffuse horizontal irradiance data obtained from a multi-filter rotating shadowband radiometer over seven different wavelength bands (416nm, 151nm, 616nm, 675nm, 870nm and 940nm and the entire spectrum) has been analyzed at Kwangju, South Korea from June 1998 December 2000. The maximum hourly global radiation flux ranged from 0.44 MJ/$m^2$ to 2.68 MJ/$m^2$ at around 11:00-12:00 Hr local time while the maximum hourly diffuse radiation flux ranged from about 0.96 MJ/$m^2$ to 1.37 MJ/$m^2$. The maximum hourly direct irradiance ranged from 1.42 MJ/$m^2$ to 2.92 MJ/$m^2$ from June1998-2000. During the period under consideration, the average monthly global radiation recorded were 13.09 MJ/$m^2$/day, 10.58MJ/$m^2$/day and 9.78MJ/$m^2$/day for years 1998, 1999 and 2000 respectively, while the diffuse irradiance were 6.54 MJ/$m^2$/day, 5.33 MJ/$m^2$/day and 5.14 MJ/$m^2$/day for f998, 1999 and 2000 respectively. The direct irradiance values at the site were 11.63 MJ/$m^2$/day, 8.24MJ/$m^2$/day and 7.75 MJ/$m^2$/day for 1998, f999 and 2000 respectively. It was observed that each of the years has its own unique meteorological parameters that affect the quality and quantity of radiation received for each month. The annual average daily fractions of the diffuse to the global radiation (KD) were 0.51, 0.61 and 0.59 for years 1998, 1999 and 2000 respectively. Analysis indicated that the average daily KD ranged from 0.13 to a maximum value of 0.99 in May for irradiance measured at the broadband channel while the maximum and minimum KD value of 0.91 and 0.23 was recorded at wavelength band 870nm and 940nm in January and September respectively. The lowest average daily clearness index (Kt) value recorded was 0.03 in May (Spring) and the annual average daily clearness indexes are 0.45, 0.34 and 0.35 for years 1998, f999 and 2000 respectively. The frequency of clear days annually at Kwangju is 67.95%, 29.57% and 40.72% for years 1998, 1999 and 2000 respectively.

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Does Fibrin Sealant Reduce Seroma after Immediate Breast Reconstruction Utilizing a Latissimus Dorsi Myocutaneous Flap?

  • Cha, Han Gyu;Kang, Sang Gue;Shin, Ho Seong;Kang, Moon Seok;Nam, Seung Min
    • Archives of Plastic Surgery
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    • v.39 no.5
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    • pp.504-508
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    • 2012
  • Background The most common complication of latissimus dorsi myocutaneous flap in breast reconstruction is seroma formation in the back. Many clinical studies have shown that fibrin sealant reduces seroma formation. We investigated any statistically significant differences in postoperative drainage and seroma formation when utilizing the fibrin sealant on the site of the latissimus dorsi myocutaneous flap harvested for immediate breast reconstruction after skin-sparing partial mastectomy. Methods A total of 46 patients underwent immediate breast reconstruction utilizing a latissimus dorsi myocutaneous island flap. Of those, 23 patients underwent the procedure without fibrin sealant and the other 23 were administered the fibrin sealant. All flaps were elevated with manual dissection by the same surgeon and were analyzed to evaluate the potential benefits of the fibrin sealant. The correlation analysis and Mann-Whitney U test were used for analyzing the drainage volume according to age, weight of the breast specimen, and body mass index. Results Although not statistically significant, the cumulative drainage fluid volume was higher in the control group until postoperative day 2 (530.1 mL compared to 502.3 mL), but the fibrin sealant group showed more drainage beginning on postoperative day 3. The donor site comparisons showed the fibrin sealant group had more drainage beginning on postoperative day 3 and the drain was removed 1 day earlier in the control group. Conclusions The use of fibrin sealant resulted in no reduction of seroma formation. Because the benefits of the fibrin sealant are not clear, the use of fibrin sealant must be fully discussed with patients before its use as a part of informed consent.

Development of the reticulum of fetuses and neonates in Korean native goats (한국재래산양의 태아 및 신생아의 제2위 발달에 관하여)

  • Huh, Chan-kwen;Kim, Chong-sup;Jung, Soon-hee
    • Korean Journal of Veterinary Research
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    • v.34 no.4
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    • pp.695-703
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    • 1994
  • The development of reticulum in fetuses between 60, 90, 120 days of gestation and neonates of Korean native goats was investigated by light, scanning electron microscopy. The results were summarized as follows; 1. In the 60-day-old fetuses, the stomach was developed and differentiated into four compartments of rumen, reticulum, omasum, and abomasum. The reticular epithelial layers were differentiated into two zones; a small dark basal and a large light luminar zones. The wall of reticulum resembled that of the rumen except that the mucosa was in the cranio-dorsal region of the reticulum. 2. In the 90-day-old fetuses, the light luminar zone of the reticulum was about 10-16 times thicker than the dark zone. The outlines of the reticular ribs were visible. 3. In the 120-day-old fetuses, the wall of the reticlum had also increased in thickness. The reticular mucosa exhibited an irregular luminar surface and the invaginations had differentiated into large regularly arranged ones separated by 3-5 and small irregularly arranged ones. 4. In the neonate, the luminar surface of the reticular mucosa demonstrated clear furrows, at which the superficial cells of the light zone had undergone degenerative changes. 5. Scanning electron microscopic studies; In the 60-day-old fetuse, numerous microvilli were observed on the superficial epithelial layer of shape or dome like at 120 days. In the neonate, the reticular papillae liked the little finger.

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Effects of stress induced by changes of water temperature on the non-specific defense mechanism in cultured olive flounder, Paralichthys olivaceus (수온 변동 자극이 양식 넙치, Paralichthys olivaceus의 비특이적 생체 방어에 미치는 영향)

  • Lee, Deok-Chan;Kim, Do-Hyung;Kim, Su-Mi;Kang, Myong-Seok;Hong, Mi-Ju;Kim, Hyun-Jeong;Park, Soo-Il
    • Journal of fish pathology
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    • v.15 no.2
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    • pp.65-75
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    • 2002
  • This study was performed to know the effects of stress induced by the daily fluctuation of water temperture from 18$^{\circ}C$ to 25$^{\circ}C$ up and down for 30 days on the defence mechanism of olive flounder. Puralichthys olivaceus. To make clear the temperature stress on the defense mechanism of the tested fish. several factors of immune response such as counting of leucocyte appearance in peripheral blood, phagocytic activity in whole blood cells, nitroblue tetrazolium(NBT) reduction, chemiluminescence(CL) response, and lysozyme activity were investigated at 28 days after giving the change of water temperature. The fish was controlled under the none feeding condition during experimental period. Mortality of the tested fish was rapidly increased up to 22% within the first one week of the experimental period without any additional stress factors. The number of neutrophil of peripheral blood in the tested group was significantly higher than the control group at the 2nd week. but the number of lymphocyte was significantly lower than the control group at the 1st and 3rd day of the experimental period. respectively. In the NBT reduction test, the activity of macrophage in the control group fish was the highest on the 7th day while that in the tested group was on the 3rd day. Also. the phagocytosis of tested group against formalin killed cells was retarded compared with the control. CL response of the tested group was significantly lower from 2nd to 5lh day of the experimental period than the control. 'The lysozyme activity of tested group was remained higher during the experimental period than the control. Even though the tested fish showed different results in some non-specific factors of immune respceses between tested and control group fish, olive flounder seems highly adaptable in repealed water temperature change in condition after one week under the given temperature fluctuation range.

Studies on the Migratory Ability of Primordial Germ Cells from Embryonic Gonads at Different Developmental Stages in Quail (메추리의 발달 중 배자 생식선에서 분리한 원시생식세포의 이동능에 대한 연구)

  • D. K. Kim;G. H. Song;J. N. Kim;D. K. Jeong;K. D. Kim
    • Korean Journal of Poultry Science
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    • v.28 no.1
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    • pp.69-76
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    • 2001
  • Avian primordial germ cells (PGCs) originate from the epiblast and appear in the germinal crescent. These PGCs enter the developing blood vessels during stage 10∼12 (H&H), circulate in the blood stream, migrate into the developing gonadal anlage and differentiate into germ cells. However, it is not clear until when the migratory ability of PGC is maintained. This study was conducted to examine whether migratory ability is present in PGCs from the gonad at later embryonic developmental stages. In the present study, gonads were dissected from 5-, 6- and 10-day old quail embryos and treated with trypsin-EDTA. Gonadal PGCs (gPGCs) were purified by Ficoll-density-gradient-centrifugation and labeled with PKH26 fluorescent dye. The PKH26-labeled gPGCs were microinjected into the blood vessel of the recipient quail embryo. Manipulated recipients were incubated for 3 days, embedded in paraffin and sdctioned. The foreign gPGCs were detected by fluorescent and confocal laser microscopy. As a result, quail gPGCs, from 10, 6 and 5 day old embryos could migrate through the recipient blood stream at early stage and settle in the gonads. Thus, results suggest that gPGCs from upto 10-day old embryos keep properties seen in circulating PGC. Therefore, the PGCs of 10-day old embryonic gonads can be used for the tools of genetic manipulation.

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Influence of milking frequency on genetic parameters associated with the milk production in the first and second lactations of Iranian Holstein dairy cows using random regression test day models

  • Damane, Moslem Moghbeli;Fozi, Masood Asadi;Mehrgardi, Ahmad Ayatollahi
    • Journal of Animal Science and Technology
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    • v.58 no.2
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    • pp.5.1-5.9
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    • 2016
  • Background: The milk yield can be affected by the frequency of milking per day, in dairy cows. Previous studies have shown that the milk yield is increased by 6.25 % per lactation when the milking frequency is increased from 2 to 3 times per day while the somatic cell count is decreased. To investigate the effect of milking frequency (3X vs. 4X) on milk yield and it's genetic parameters in the first and second lactations of the Iranian Holstein dairy cows, a total of 142,604 test day (TD) records of milk yield were measured on 20,762 cows. Results: Heritability estimates of milk yield were 0.25 and 0.19 for 3X milking frequency and 0.34 and 0.26 for 4X milking frequency throughout the first and second lactations, respectively. Repeatability estimates of milk yield were 0.70 and 0.71 for 3X milking frequency and 0.76 and 0.77 for 4X milking frequency, respectively. In comparison with 3X milking frequency, the milk yield of the first and second lactations was increased by 11.6 and 12.2 %, respectively when 4X was used (p < 0.01). Conclusions: Results of this research demonstrated that increasing milking frequency led to an increase in heritability and repeatability of milk yield. The current investigation provided clear evidences for the benefits of using 4X milking frequency instead of 3X in Iranian Holstein dairy cows.