• 수산해양기술연구
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• 제36권4호
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• pp.281-286
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• 2000

저층트롤 실물 어구를 이용한 해상 실험을 통하여 예망 중인 어구의 망구 형태에 관련되는 전개판의 간격 및 망고 등을 예망 속도별, 끌줄의 길이별로 측정하고, 이론적인 수치 해석 결과와 비교하여 실물어구의 수중 현황을 해석함으로서 어구의 효율적인 운용과 어획효과의 증대를 위한 기초자료를 제공하고자 한다. 수중 현황을 해석한 결과를 요약하면 다음과 같다. 1. 전개판의 전개간격은 예망 속도와 끌줄길이의 증가에 따라 직선적으로 증가하며 끌줄 길이에 의한 증가율이 예망 속도에 의한 증가율보다 현저히 크게 나타났으며, 그 간격의 변화는 57.0∼82.8m로서 후릿줄과 그물목줄 및 그물길이 전체의 43∼62%를 차지하였다. 2. 망구의 높이는 예망 속도와 끌줄길이의 증가에 따라 직선적으로 감소하며, 예망 속도에 의한 감소율이 끌줄 길이에 의한 감소율보다 현저히 크게 나타났는데 그 높이의 변화는 3.1∼4.0m로 나타났다. 3. 양 날개끝의 간격이 커지면 망고는 낮아지나 끌줄 길이가 증가할수록 날개 끝 간격의 증가에 대한 망구 높이 감소율의 비는 점차 작아졌다. 4. 망고에 대한 양 날개 끝 간격의 비는 예망속도와 끌줄 길이의 증가에 따라 점차 커졌는데, 그 비는 4.17∼7.81로 나타났다.

• Clinical and Experimental Pediatrics
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• 제59권7호
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• pp.292-297
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• 2016

Purpose: To compare different regimens of vitamin D with respect to its serum increment levels and bone mineral accrual in vitamin D-deficient children. Methods: Children identified as being vitamin D deficient (serum levels<20 ng/mL) were divided into 3 treatment groups by stratified block randomization (group 1, 4,000 IU/day of vitamin D3 plus 50 mg/kg/day calcium for 12 weeks; group 2, 30,000 IU/wk of vitamin D3 plus 50 mg/kg/day calcium for 12 weeks; and group 3, 300,000 IU of vitamin D3 once intramuscularly plus 50 mg/kg/day calcium). After regimen completion, each child received a maintenance dose of 400 IU/day vitamin D3 plus 50 mg/kg/day calcium. Their serum vitamin D level was measured after 3 and 12 months. Total body less head bone mineral concentration (BMC) and total body less head bone mineral density (BMD) were measured after 12 months. Results: The mean increment in serum vitamin D levels from baseline to 3 months was significantly higher in group 3 than in groups 1 and 2, but the levels from 3 to 12 months were almost similar among all 3 groups. There were no significant differences among the 3 groups with respect to percentage increase of BMD and BMC. Conclusion: The injectable form of vitamin D was more efficacious than the oral forms in increasing the serum level to the normal range. All 3 regimens were equally effective in increasing the BMC and BMD. The 400 IU/day maintenance dose was sufficient to keep the serum level within the normal range.

• 대한환경공학회지
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• 제35권11호
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• pp.776-780
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• 2013

본 연구에서는 마이크로파 조사를 통하여 디젤오염토양의 TPH (Total Petroleum Hydrocarbon) 제거양상을 살펴보고자 하였다. 건조토양을 마이크로파로 조사하였을 때 토양 내 온도의 상승은 완만하였으나 수분이 공급된 상태에서 온도 상승이 급격하게 나타났다. 함수량이 20% 이내 범위에서는 수분함량이 증가할수록 온도가 상승하였으나 20% 이상에서는 오히려 온도가 저하되었다. 100~700 W의 전력량으로 마이크로파를 조사한 후 각각의 TPH의 제거량을 확인하였을 때 300 W 이상의 범위에서는 전력량이 높아짐에도 TPH 제거량에 차이가 많지 않았다. 초기 수분량 20%에서 마이크로 조사 시 최종 TPH 제거량은 60%로 나타났으나 추가적으로 수분을 공급하여 토양 내 함수량을 일정하게 유지하였을 때 약 25%의 TPH 제거 증대효과가 나타났다. 이는 마이크로파를 이용할 때 반응이 지속됨에 따라 수분손실과 더불어 온도가 감소하므로 토양 내 함수량을 유지하는 것이 효율적인 TPH제거를 위해 중요한 요인이 될 수 있다는 것을 나타낸다.

• 한국농공학회논문집
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• 제56권2호
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• pp.37-46
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• 2014

Water for crop growth were supplied by irrigation in protected cultivation and these are accumulated in the soil and utilized for crop evapotranspiration. The study for analyzing soil moisture characteristics is necessary for adequate irrigation water and soil water management in protected cultivation. Soil moisture content, irrigation water quantity and meteorological data were monitored to analyze soil moisture increment and extraction characteristics in terms of soil layers and cucumber crop growth stages. In first cropping period, the total amount of irrigation water was 5.07 mm/day, soil moisture increment was 4.82 mm/day and soil moisture extraction was 5.56 mm/day. In second cropping period, the total amount of irrigation water was 4.82 mm/day, soil moisture increment was 4.65 mm/day and soil moisture extraction was 4.73 mm/day. Soil moisture extraction rate from 0 to 75 cm is 90.3 % in first cropping period and 79.1 % in second cropping period. The majority irrigation water were consumed in root zone, however, about 15 % of soil moisture were losses by infiltration in lower soil layer. Soil moisture extraction and extraction pattern of cucumber crop calculated in this study can be utilized as a basic data for irrigation water management in protected cultivation.

• 한국자원식물학회지
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• 제26권6호
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• pp.709-717
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• 2013

The objective of this study was to examine the effect of root pruning intensity in combination with different initial seedling size on the growth of transplanting seedlings of Quercus acutissima. One-year-old seedlings were divided into three groups depending on their height, i.e. small (< 15 cm), medium (25-35 cm) and large size (35 cm <). Root of seedlings was pruned by three intensity such as, leaving 5 cm (severe), 10 cm (medium) and 15 cm (light) of taproot from the root-collar. After one year, we investigated survival rate, height and root-collar diameter (RCD) increment and final shoot dry weight. Also we measured characteristics of newly developed lateral roots such as number, total length, dry weight and diameter. Severe root pruning showed the lowest survival rate in all seedling size. Height increment, RCD increment and shoot dry weight were decreased with increasing intensity of root pruning. Seedlings of medium and light root pruning showed similar above-ground growth and dry weight of lateral roots. More large seedlings showed good survival rate, height increment and final shoot dry mass in all root pruning intensity. Therefore, one-year-old seedlings of Q. acutissima should be pruned taproot by 10 cm and transplanted to obtain excellent performance and increase the efficiency of transplanting work. Based on the findings of this study, it is important that applying to different root pruning intensity depending on initial seedling size for producing 2-year-old seedlings with excellent growth and high quality.

• 한국농공학회지
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• 제30권4호
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• pp.134-153
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• 1988

This paper was carried out to investigate the existence of a unique stress- strain behavior by obtaining some factors influencing the time dependent stress- strain behavior of clay. The results obtained from this study were summarized as follows ; 1. The relationship between stress ratro and strain in normally consolidated clay was in- dependent on pre-shear consolidation pressure. Therefore, shear strain could be expressed as a function with stress ratio. 2. The constitutive equation of shear strain on Modified Carn Clay Model coincided better with the observed value than Cam Clay Model. 3. The relationships between deviator stress and shear strain, between pore water pressure and shear strain were unified by the mean equivalent pressure. 4. The shear strain contour in norrnally consolidated clay was increased linearly through origin, but that in overconsolidated clay was not in accordance with the result of the former. 5. Because the effective stress path of normally consolidated clay was unified by the mean equivalent pressure, state boundary surface in (e,p,q) space was transformed into two dimensional surface. But it was considered to be suitable that the unified stress- strain in overconsolidated clay be expressed by a function with overconsolidation ratio. 6. The deviator for constant strain was increased linearly with increment of strain rate ($\varepsilon$) on semi-log scale, but pore water pressure was decreased. 7. The behavior of stress relaxation was transformed from linear to curvilinear with inc - rement of strain rate before stress relaxation test, and pore water pressure was increased in total range. 8. The strain of creep was increased linearly with increment of time on semi-log scale. The greater the strain rate before creep test became, the greater the increment of strain of creep became. And the pore water pressure during creep test was increased generally with increment of time on semi-log scale.

• 한국수산과학회지
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• 제32권5호
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• pp.550-555
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• 1999

경남 사천시 신수도 연안에서 1988년 3월 20일부터 5월 1일까지 약 15일 간격으로 4회 채집한 표본으로부터 까나리 치어의 일령, 성장 및 산란 시기를 조사하였다. 일령 형질로는 이석을 사용하였고, 윤문은 불투명대에서 투명대로 이행하는 경계로 하였다. 일륜은 1일 1개 형성되었고, 산란 시기는 1987년 11월3일부터 1988년 3월8일까지로 추정되었다. 이석경 (R)과 전장(TL)간의 관계식은 TL=25.336+232.895R이었고, 전장 (TL)과 체중 (BW)간의 상대 성 장은 $BW=1.27{\times}10^{-7}TL^{3.707}$으로 나타났다. 치어의 성장식은 von Bertalanffy model에 의하면, $TL=87.80(1-e^{-0.0074(t+10.79)})$로 나타났으며 , Gompertz model에 의하면 $TL=72.59 e^{-1.8417\;e-0.0152t}$로 추정되었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.613-616
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• 1999

The bond between reinforcing bar and concrete is a significant factor to confirm that they behave uniformly in the reinforced concrete. Thus, the studies on this field have been conducted by many researchers. But for the high strength lightweight concrete few studies have been done. In this study, the steel fiber reinforced high strength lightweight concrete developed to complement the brittleness of the high strength lightweight concrete was studied experimentally to find the local bond stress. Total 20 specimens were tested and the measured test values were compared with those calculated according to ACI 318-95 code and CEB-FIP code, respectively. The results indicate that the maximum bond stress has been influenced by increment of volume fracture of steel fiber, compressive strength and cover, Especially steel fiber caused not only increment of bond strength but also ductile behaviro.

• 물과 미래
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• 제12권1호
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• pp.60-71
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• 1979

In general, the lock structure is built at place of having great deal range for dealing with effective ships operation such as in the west coast of Korea. In Inchon harbour, the two locks of 10 KT and 50 KT tonnage class in total has been constructed for several years age, however, it has been recorded many waiting vessels at outer harbour due to the increment of oceangoing vessels & shortage of berthing facilities in accordance with beyond expectation of cargo amount increment. This paper attempts to solves the waiting vessels problem at outer harbour by simulation in applying queing theory. It is found that the simulation results such as average queue time, service time, and queue length during lock operation can be applied to find the minimum of the cost function for determination of optimum Lock Size

• The Korean Journal of Physiology
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• 제2권1호
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• pp.17-21
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• 1968

Total body oxygen uptake was measured in rats following hemorrhage (16 rats) and blood transfusion (7 rats) under light Nembutal anesthesia. Arterial blood Pressure measured on the tail artery decreased or increased following hemorrhage or transfusion. No direct relationship was observed between arterial blood pressure alteration and oxygen intake variation. Hematocrit ratio which changed after hemorrhage or transfusion showed a direct relationship with oxygen intake. Decrease in hematocrit ratio resulted in a decrease in oxygen intake of rats. The correlation coefficient between decrement of hematocrit ratio and decrement of oxygen intake was r=.56. The correlation coefficient between increment of hematocrit ratio and increment of oxygen intake was r=.86. Thus it was concluded that alteration in oxygen intake was limited by the systemic oxygen transport capacity of blood.