• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.1
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• pp.35-44
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• 2005

Microclimate of Gwangneung forest watershed is characterized by analyzing wind, radiation, profiles of air temperature and humidity, soil and bole temperature, precipitation and soil water content measured at and around the flux tower from April 2000 to September 2003. Mountain-valley wind was prevalent due to the topographic effect with dominant wind from east during daytime and relatively weak wind from west during nighttime. Air temperature reaches its peak in July-August whereas monthly-averaged incoming shortwave radiation shows its peak in May due to summer monsoon. Albedo ranges from 0.12 to 0.16 during the growing season. Monthly-averaged bole temperature is in phase with monthly- averaged air temperature which is consistently higher. Monthly-averaged soil temperature lags behind air temperature and becomes higher with leaf fall. With the emergence of leafage in April, maximum temperature level during midday shifts from the ground surface to the crown level of 15-20m in May. Profiles of water vapor pressure show a similar shift in May but the ground surface remains as the major source of water. Vapor pressure deficit is highest in spring and lowest in winter. Monthly averaged surface soil temperatures range from 0 to 20℃ with a maximum in August. Monthly averaged trunk temperatures of the dominant tree species range from -5.8 to 21.6℃ with their seasonal variation and the magnitudes similar to those of air temperature. Annual precipitation amount varies significantly from year to year, of which >60% is from July and August. Vertical profiles of soil moisture show different characteristics that may suggest an important role of lateral movement of soil water associated with rainfall events.

• Journal of Korea Foresty Energy
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• v.25 no.2
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• pp.9-15
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• 2006

The quality of wood is largely depend on the characteristics of xylem tissue and their variation. They may include tracheid length, microfibril angle, distribution and amount of resin canal, as well as specific gravity as indicator of material properties. In this study, variation of these elements between and within 30 superior families of Pinus densifloa in progeny test forest were examined and the results are as follows; In terms of elongation ratio of tracheid length which is less than 1%, the sample tree showed a transition to matured wood after 13 years particularly in Kangwon 25, 30, 90, 56 and Chungnam 4 families. The average specific gravity were from 0.35 to 0.49, and differences between the families were significant. Number of transverse resin canal per unit area were also found to be significant between the families. The microfibril angles measured at 15th ring number ranged from 0.9 degree to 28.6 degree. More studies are necessary to tell whether these variation is inherited by genetic or individual characteristic. However it would be desirable that these elements be considered as key elements in the early stage of selection process of superior tree to ensure good quality of wood production in future.

• Korean Journal of Ecology and Environment
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• v.36 no.1 s.102
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• pp.57-65
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• 2003

The algal growth potential test (AGPT) bioassay were conducted to assess the water quality and fertility in the Chinyang Reservoir and the lower part of the Nam River from August 2000 to July 2001, The AGPT value of the Chinyang Reservoir ranged from 0 to 23.4 mg dw $1^{-1}$, while 79% of the algae cultivation have not grown. The AGPT value was in proportion to phosphorus concentration of the water, and it was less when chlorophyll-a was high. This value was higher in the middle and lower layers than in the upper layer, and in the inflow part where the water is shallower than in the lacustrine. The AGPT value has increased in the whole reservoir in August${\sim}$September when the water volume is high. In contrast, the AGPT value in the Nam River varied greatly compared to that of the reservoir, and ranged from 0 to 252.0 mg dw $1^{-1}$ and 65% of the algae cultivation have grown. The value was less than 10 mg dw $1^{-1}$ in the upstream, over the point where the treated wastewater discharged. It was 57 mg dw $1^{-1}$ on the average in the downstream, except in March and July when the discharged water influenced greatly, exceeding the hypertrophic condition. The result of AGPT shows the differences in the time and space on the reservoir and the streams. The AGPT value has increased in July${\sim}$September, and in December in the inflow part of the reservoir; in March and August${\sim}$December in the lower part; and in January, May, and November in the streams. AGPT is useful not only in defining the influence of the limiting nutrients on the algal growth, but also in evaluating the nutrients fertility in the inland water.

• Journal of Animal Environmental Science
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• v.9 no.2
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• pp.69-78
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• 2003

In this study, the energy conversion equipment from the radiation energy to mechanical energy by using n­pentane as the operating fluid was constructed and the performance to pump the water was tested for the utilization of solar powered water pump. The equipment was designed optimally, after the theoretical analyses of the water pumping head and water quantity per cycle were done. The pentane vapour temperature in the condenser and the temperature of the outlet water from the condenser became lowered and the heat transfer rate became higher with decreasing the water inlet level to the condenser. The temperature difference between the condenser and the water tank was significant. Therefore, the distance between the water tank and condenser was recommended to be shorten and the diameter of their connecting pipe was recommended to be narrow in order to reduce the resistance of the fluid passage and improve the heat transfer rate. The amount of water pumped was 1.6­2.4 liters. Mass flow rate of the cooling water became lowered when the cooling water pipe was prolonged from the condenser to improve the heat transfer rate.

• Journal of Yeungnam Medical Science
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• v.1 no.1
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• pp.101-106
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• 1984

Before beginning the extracorporeal circulation, perfusionists should supply oxygen into the oxygenator and establish blood flow through the blood line of the heart-lung machine. But these manipulation can induce severe hypocarbic state of priming solutions due to wash out of $CO_2$ gas in the solution. This study was carried out to examine the relationship of blood gas changes between hypocarbic priming solutions and body circulation in 15 patients undergoing open heart surgery with extracorporeal circulation. $PaCO_2$, pH, buffer base and $PaO_2$ were measured from priming solutions before and 15 minutes after the extracorporeal circulation. The results were as follows; 1) Before the extracorporeal circulation, mean $PaCO_2$ level was $12.1{\pm}7.8mmHg$ in the priming solution. However, 15 minutes after extracorporeal circulation, the $PaCO_2$ level was maintained at $35.7{\pm}5.7mmHg$. 2) pH in the priming solution was variable from 6.93 to 7.99 (mean $7.45{\pm}0.29$), but after 15 minutes it was ranged from 7.28 to 7.42 (mean $7.35{\pm}0.05$). 3) Mean buffer base level in the priming solution was $7.9{\pm}3.5mmol/l$, but after 15 minutes, it was $19.6{\pm}1.2mmol/l$. 4) Mean $PaO_2$ level in the priming solution was $667.1{\pm}45.6mmHg$, but after 15 minutes, it was $280.7{\pm}131.7mmHg$.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.2
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• pp.120-129
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• 2012

We investigated seasonal variation of sediment-water oxygen and inorganic nitrogen fluxes, and denitrification at tidal flat sediments located in the Nakdong River Estuary from July 2005 to September 2006. Net oxygen fluxes, measured with sediment incubations at in situ temperature, varied from -37.0 to $0.5mmol\;O_2\;m^{-2}\;d^{-1}$. Oxygen fluxes into the sediments from the overlying water increased due to the increased water temperature. Denitrification rate ($4{\sim}2732{\mu}mol\;N\;m^{-2}\;d^{-1}$) in this study was higher compared to the other Korean coast measured with the same method. Denitrification showed the same seasonal variation as oxygen fluxes. Denitrification rate based on $^{15}N$-nitrate showed a strong correlation with nitrate flux into the sediments from the overlying water. Denitrification via "water column supplied nitrate ($D_w$)", calculated from Isotope pairing technique, also correlated well with nitrate flux into the sediments. Nitrate from water column seems to account for seasonal variation of denitrification in Nakdong River Estuary. To understand general patterns and trends of biogeochemical processes of sediments in the Nakdong River Estuary, we categorized biogeochemical fluxes measured in this study according to direction and sizes of fluxes. Type 1(high oxygen and inorganic nitrogen fluxes into the sediments and high denitrification) occurred in summer, whereas Type 2(low oxygen and inorganic nitrogen fluxes into the sediments and low denitrification) occurred in rest of the season. Intertidal flat sediments seem to react sensitively to influence of freshwater from the Nakdong River.

• Parasites, Hosts and Diseases
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• v.35 no.4
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• pp.259-264
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• 1997

This study was carried out to determine whether dermal mast cell responses to Parasoninn westemoni in an abnormal host, the mouse, were dependent on the site of metacercarial inoculation. In mice during subcutaneous infection, the number of der- mal mast cells were increased significantly (p<0.05) at the first week ($38.3/\textrm{mm}^2$) and then persisted at a high level until the sixth week ($45.2/\textrm{mm}^2$) of infection compared with PBS- injected (control) mice (range: $19.4-25.1/\textrm{mm}^2$). In mice during oral infection, the number of dermal mast cells were increased significantly (p<0.05) at two weeks ($33.5/\textrm{mm}^2$) after infection and remained at these levels thereafter compared loth non-infected (control) mice (range: $17.4-22.3/\textrm{mm}^2$). In mice both during subcutaneous and oral infection, the recruited dermal mast cells showed extensive degranulation at the second week (68.4%) and 60.7%, respectivelyl, reached a peak at the third week (81.4%, and 92.1%, respectively) and then declined slightly thereafter. By contrast, in both control mice, about 10% of dermal mast cells were degranulated. In conclusion, this study suggests that dermal mast cell responses to p. westemcni in mice are dependent on cutaneous sensitization by larval excretory-secretory antigens, irrespective of infection route.

• Journal of Korean Society of Steel Construction
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• v.20 no.6
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• pp.723-730
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• 2008

Due to the higher ratio of live load to total loads of railway bridges, the accumulated damage by cyclic fatigue is significant. Moreover, it is highly possible that the initiated crack grows faster than that of highway bridges. Therefore, it is strongly needed to assess the safety for the accumulated damage analytically. The initiation and growth of fatigue-crack are related with the stress range, number of cycles, and the stiffness of the structural system. The stiffness of the structural system includes uncertainties of the planning, design, construction and maintenance, which varies as time goes. In this study, the authors developed the design and risk assessment techniques based on the reliability theories considering the uncertainties in load and resistance. For the probabilistic risk assessment of crack growth and the remaining life of the structures by the cyclic load of railway and subway bridges, response surface method (RSM) combined with first order second moment method were used. For composing limit state function, the stress range, stress intensity factor and the remaining life were selected as input important random variables to the RSM program. The probabilities of failure and the reliability indices of fatigue life for the considered specimen under cyclic loads were evaluated and discussed.

• Korean Journal of Weed Science
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• v.4 no.2
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• pp.135-142
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• 1984

To obtain the basic information for weed management in polder land, a colligated assessment on weed distribution and it`s plant sociological indices on Gyewha polder land were arranged. At the situation of assessment, the Gyewha polder land was reclaimed with aim with paddy-rice production. As a result of reclamation, the salinity of most soil samples were below 0.3%, and acidity ranged from pH 5.5 to 6.5. Total weed species were counted as much as 17 species (3 gramineae, 7 cyperucese, and 8 broad-leaved species), and a most dominant species, Scirpus maritimus, were succeeded with Monochoria v., Eleocharis a., and Cyperus d., etc. by reclamation. Declining of soil salinity and soil pH, the number of weed species, individuals, biomass, species diversity, evenness, sociability index were increased, but the population particularity was weaken in tendencies. By developing of reclamation, the weed species which is summer annual broad leaf, wind and water disseminating, and tussock formed species are increased instead of salt-resistant, perennial cyperus, and rhizomatous extending species.

• The Korean Journal of Nuclear Medicine
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• v.28 no.2
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• pp.200-205
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• 1994

그레이브스 갑상선기능항진증은 자가면역질환의 하나로 방사성 옥소가 간편하고 경제적이며 효과적인 치료법임이 알려져 있는데 방사성 옥소 투여 후 갑상선 조직의 자극 및 파괴에 따라 각종 항원의 노출의 증가와 이에 대한 자가항체의 변동이 예상된다. 저자들은 추정 갑상선 무게를 고려한 6-10 mCi의 방사성 옥소를 투여 받은 그레이브스 갑상선기능항진증 환자 90명을 2년간 추적하여 치료 전 후의 혈청 갑상선자극 면역글로불린(TBIIl)활성도와 thyroglobulin 및 antithyroglobulin antibody의 변화를 관찰하였다. 1) 대상환자 90명의 연령분포는 14-58세(중앙치 30)였으며 여자가 72명(80%)이었다. 2) 평가대상 환자 중 치료 전 TBIIl 활성도가 정상범위였던 경우는 15명(30%)이었고 증가된 경우는 35명(70%)이었다. 치료 전보다 치료 3개월 후에 TBII 활성도가 더 증가된 경우는 31명(62% )이었다. 3) TBII 활성도가 치료 전에 증가하였거나, 치료 전에 정상범위였다가 치료 3개월 후에 증가한 환자의 TBII 활성도의 동태는 치료 3개월 후에 가장 높았고 그 후 점차 감소하였다. 이들의 TBIIl 활성도가 15%이내로 정상화된 정도는 치료 후 6개월에 40%, 12개월에 82%였다. 4) 치료 전 antithyroglobulin antibody가 양성인 경우 80%에서 3개월 후에도 혈청 thyroglobulin의 동태는 치료 3개월 후에 높았다가 증가가 없었으며 치료 전 antithyroglobulin antibody가 음성인 경우 60%에서 치료 3개월 후에 혈청 thyroglobulin의 증가가 있었다. 5) antithyroglobulin antibody가 음성인 경우의 혈청 thyroglobulin의 동태는 치료 3개월 후에 높았다가 점차 감소하는 경향을 보였으며 antithyroglobulin antibody가 양성인 경우의 혈청 thyroglobulin의 동태는 치료 후 시간이 지남에 따라 점차 감소하였다. 6) 치료 전 antithyroglobulin antibody가 음성인 경우 치료 후 시간 경과에 따라 동시에 측정한 혈청 TBII 활성도와 thyroglobulin 사이에는 통계적으로 유의한 상관관계가 있었다(p<0.01). 한편 치료 전 antithyroglobulin antibody가 양성인 경우 치료 후 시간 경과에 따라 동시에 측정한 혈청 TBII 활성도와 thyroglobulin 사이에는 통계적으로 유의한 상관관계가 없었다(p= 0.16). 이상의 결과로 방사성 옥소를 투여 받은 그레이브스 갑상선기능항진증 환자에서 혈청 TBII 활성도는 항갑상선제를 투여 받은 경우와는 달리 초기에 증가하였다가 시간이 지남에 따라 점차 감소함을 알 수 있었으며 그 감소 정도는 항갑상선제만을 쓴 경우보다 더 빠를 것으로 생각된다. 따라서 혈청 TBII 활성도와 thyroglobulin은 방사성 옥소 치료효과의 관찰에 중요한 역할을 할 것으로 생각되며 특히 antithyroglobulin antibody가 음성인 경우 혈청 thyroglobulin은 혈청 TBII 활성도를 반영할 것으로 사료된다.