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Estimate of Heat Flux in the East China Sea (동지나해의 열속추정에 관한 연구)

  • KIM Young-Seup
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.1
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    • pp.84-91
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    • 1996
  • Heat flux of the East China Sea was estimated with the bulk method, the East China mount based on the marine meteorological data and cloud amount data observed by a satellite. Solar radiation is maximum in May and minimum in December. Its amount decreases gradually southward during the winter half year (from October to March), and increases northward during the summer half year (from April to September) due to the influence of Changma (Baiu) front. The spatial difference of long-wave radiation is relatively small, but its temporal difference is quite large, i.e., the value in February is about two times greater than that in July. The spatial patterns of sensible and latent heat fluxes reflect well the effect of current distribution in this region. The heat loss from the ocean surface is more than $830Wm^{-2}$ in winter, which is five times greater than the net radiation amount during the same period, The annual net heat flux is negative, which means heat loss from the sea surface, in the whole region over the East China Sea. The region with the largest loss of more than $400Wm^{-2}$ in January is observed over the southwestern Kyushu. The annual mean value of solar radiation, long-wave radiation, sensible and latent heat fluxes are estimated $187Wm^{-2},\;-52Wm^{-2},\;-30Wm^{-2}\;and\;-137Wm^{-2}$, respectively, consequently the East China Sea losses the energy of $32Wm^{-2}(2.48\times10^{13}W)$. Through the heat exchange between the air and the sea, the heat energy of $0.4\times10^{13}W$ is supplied from the air to the sea in A region (the Yellow Sea), $2.1\times10^{13}W$ in B region (the East China Sea) and $1.7\times10^{13}W$ in C region (the Kuroshio part), respectively.

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Study on Measurements of the Mandible BMD According to the ROI Variation (관심영역 변화에 따른 하악골 골밀도 측정에 대한 연구)

  • Tak, Jeong-Nam
    • Journal of radiological science and technology
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    • v.32 no.3
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    • pp.271-276
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    • 2009
  • The aim of this study was to evaluate the effect of Bone Mineral Density(BMD) at mandible. So, we studied how to measure the BMD at mandible using DEXA(Dual energy X-ray absorptiometry, DEXA) by Horner er al (1996) and knew reproducibility of the measurements. Thirty-five patients (13 men, 22 women, mean age : 25.4 years) were examined using the GE Lunar Prodigy Advance(LUNAR Corporation, madison, USA). They were examined in Semiprone position of their body and true lateral position of their mandible selected the Lumbar lateral mode. We used the custom mode in analysis when ROI (area $30{\times}2.5\;mm^2$). Three ROIs ($30{\times}2.5\;mm^2$, $50{\times}2.5\;mm^2$, $20{\times}2.5\;mm^2$) were located each at the two different sites of the mandible (angle of mandible and mental symphysis) and BMD was measured. Differences in BMD measurement was statistically compared according to the size and location of ROI. BMD was $1.320{\pm}0.358g/cm^3$ in men and was $1.152{\pm}0.340g/cm^3$ in women. BMD at the angle of mandible was $1.201{\pm}0.361g/cm^3$ in men and was $1.025{\pm}0.377g/cm^3$ in women. BMD of men at the mental symphysis was $1.434{\pm}0.341g/cm^3$ and that of women was $1.19{\pm}0.358g/cm^3$. With the ROI of $20{\times}2.5\;mm^2$, BMD was $1.262{\pm}0.384g/cm^3$ in men and was $1.113{\pm}0.357g/cm^3$ in women. With the ROI of $50{\times}2.5\;mm^2$, BMD of men was $1.320{\pm}0.358g/cm^3$ and that of women was $1.129{\pm}0.340g/cm^3$. There was a statistically significant difference of BMD according to the size and location of ROI. When measuring mandible BMD, there are good for increasing ROI and locate between ramus and mental symphysis. Especially following exam, refer to same size and location with fore exam. According to study which measure mandible BMD, It's correct to measure better a portion of mandible then whole of BMD. Using DEXA protocol is studied good for the additional study to compare the BMD at mandible. Later date, It will be good for measurement value in implant and bone graft quantitatively. Using DEXA method gain BMD threshold value in korean.

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Efficacy of Pamidronate in Nephropathic Children with Ongoing Long Term Corticosteroid Therapy (장기 스테로이드 치료요법 중인 신질환 환자에서 Pamidronate의 효과)

  • Hong Hyun-Kee;Kim Eun-Seong;Kim Sung-Do;Cho Byoung-Soo
    • Childhood Kidney Diseases
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    • v.8 no.1
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    • pp.43-50
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    • 2004
  • Background : Steroid-induced osteoporosis(SIO) is one of the serious complications of long-term steroid therapy, especially in growing children. Recently bisphosphonates have been used to treat or prevent SIO in adult, which is rare in children with glomerular diseases. We studied the effect of pamidronate on SIO using dual energy X-ray absorptiometry and biochemical markers of bone turnover. Methods : Forty four children receiving moderate-to-high doses of steroids were enrolled. They had no history of bone, liver, or endocrine disease. Patients were stratified by their baseline bone mineral density(BMD) findings. All patients received corticosteroids for 3 month and oral calcium supplementation(500 mg/day) daily. Among them, 28 patients were treated with placebo and 16 were treated with pamidronate(125 mg) for 3 months. Blood chemistry and bone mineral density(BMD) were measured at baseline, and 3months. In addition, parathyroid hormone(PTH), serum osteocalcin, and urinary dipyridinoline levels were evaluated. Results : In overall population, the mean lumbar spine BMD decreased from $0.754{\pm}0.211(g/cm^2)$ to $0.728{\pm}0.208(g/cm^2)$ in the placebo group(P<0.05) and increased from $0.652{\pm}0.194(g/cm^2)$ to $0.658{\pm}0.226(g/cm^2)$ in the pamidronate group(P>0.05). Conclusion : Pamidronate appears to be effective in preventing SIO in children with glomerular diseases requiring long-term steroids therapy. Further careful observation and follow-up might be needed for children receiving bisphosphonates such as pamidronate.

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Improved Activity Estimation using Combined Scatter and Attenuation Correction in SPECT (단일광자방출단층촬영 영상에서 산란 및 감쇠 보정에 위한 절대방사능 측정)

  • Lee, Jeong-Rim;Choi, Chang-Woon;Lim, Sang-Moo;Hong, Seong-Wun
    • The Korean Journal of Nuclear Medicine
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    • v.32 no.4
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    • pp.382-390
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    • 1998
  • Purpose: The purpose of this study was to evaluate the accuracy of radioactivity quantitation in Tc-99m SPECT by using combined scatter and attenuation correction. Materials and Methods: A cylindrical phantom which simulates tumors (T) and normal tissue (B) was filled with varying activity ratios of Tc-99m. We acquired emission scans of the phantom using a three-headed SPECT system (Trionix, Inc.) with two energy windows (photopeak window: $126{\sim}154keV$ and scatter window: $101{\sim}123keV$). We performed the scatter correction with dual-energy window subtraction method (k=0.4) and Chang attenuation correction. Three sets of SPECT images were reconstructed using combined scatter and attenuation correction (SC+AC), attenuation correction (AC) and without any correction (NONE). We compared T/B ratio, image contrast [(T-B)/(T+B)] and absolute radioactivity with true values. Results: SC+AC images had the highest mean values of T/B ratios. Image contrast was 0.92 in SC+AC, which was close to the true value of 1, and higher than AC (0.77) or NONE (0.80). Errors of true activity by SPECT images ranged from 1 to 11% for SC+AC, $22{\sim}47%$ for AC, and $2{\sim}16%$ for NONE in a phantom which was located 2.4cm from the phantom surface. In a phantom located 10.0cm from the surface, SC+AC underestimated by 24%, NONE 40%. However, AC overestimated by 10%. Conclusion: We conclude that accurate SPECT activity quantitation of Tc-99m distribution can be achieved by dual window scatter correction combind with attenuation correction.

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The Optimal TDN Levels of Concentrates and Slaughter Age in Hanwoo Steers (거세한우에 있어서 배합사료의 적정 TDN 수준과 도축 월령)

  • Kim, K.H.;Lee, J.H.;Oh, Y.G.;Kang, S.W.;Lee, S.C.;Park, W.Y.;Ko, Y.D.
    • Journal of Animal Science and Technology
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    • v.47 no.5
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    • pp.731-744
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    • 2005
  • Ninety Hanwoo steers(initial BW=167.2$\pm$13.4kg) were used to determine the effect of energy concentrations in concentrates and slaughter age on performance, carcass characteristics. Steers were allotted by BW to one of eighteen pens. Eighteen pens were randomly allotted to a low(70-70-71-72% for the growing, the early, the middle or the late fattening periods), medium(70-71-72-73%) or high(70-72- 73-74%) TDN level of concentrates. Five steers for each treatment of energy level were slaughtered every one month from 26 month of age to 31 month of age. Concentrates was fed restrictedly to achieve a predicted gain of 0.7-0.9kg from growing stage to middle fattening stage. All steers were fed orchard grass(Dactylis glomerata L.) hay as roughage during the growing period, fed rice straw gradually substituted for orchard grass hay during the early fattening period, and fed rice straw only thereafter. Overall body weight and feed intake were not affected by TDN levels of concentrates. Average daily gain for all treatments was higher than 0.9kg/d during the 19-21 month of age and decrease thereafter, but sustained above 0.7kg/d. Mean concentrates intake for all treatments was 1.0-1.3% of live BW during the growing period and 1.5% during the early fattening. Thereafter, it decreased up to 1.4% during the middle fattening and 1.0% during late fattening period. Delay of slaughter end point resulted in a gradual increase of rib-eye area, back fat thickness and marbling score, especially after slaughter age of 29 month there was significant increases(P<0.05). The appearance rate of 1+ and 1 grade related to the slaughter ages was 100% at 29, 30 and 31 months of age, whereas those at 26, 27 and 28 months were 93, 86 and 80%, respectively. Dressing rate was significantly(P<0.05) increased and rate of retailed cut weight significantly(P<0.05) decreased when slaughter age increased. In economic analysis, there was pronounced increase in net income up to 32-46% after slaughter age of 29 months. Under the conditions of this study, high TDN intake is not necessarily required for high quality Hanwoo meat production and slaughter age of 29 month might be the optimum for Hanwoo steers.

Impact of Sulfur Dioxide Impurity on Process Design of $CO_2$ Offshore Geological Storage: Evaluation of Physical Property Models and Optimization of Binary Parameter (이산화황 불순물이 이산화탄소 해양 지중저장 공정설계에 미치는 영향 평가: 상태량 모델의 비교 분석 및 이성분 매개변수 최적화)

  • Huh, Cheol;Kang, Seong-Gil;Cho, Mang-Ik
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.13 no.3
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    • pp.187-197
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    • 2010
  • Carbon dioxide Capture and Storage(CCS) is regarded as one of the most promising options to response climate change. CCS is a three-stage process consisting of the capture of carbon dioxide($CO_2$), the transport of $CO_2$ to a storage location, and the long term isolation of $CO_2$ from the atmosphere for the purpose of carbon emission mitigation. Up to now, process design for this $CO_2$ marine geological storage has been carried out mainly on pure $CO_2$. Unfortunately the $CO_2$ mixture captured from the power plants and steel making plants contains many impurities such as $N_2$, $O_2$, Ar, $H_2O$, $SO_2$, $H_2S$. A small amount of impurities can change the thermodynamic properties and then significantly affect the compression, purification, transport and injection processes. In order to design a reliable $CO_2$ marine geological storage system, it is necessary to analyze the impact of these impurities on the whole CCS process at initial design stage. The purpose of the present paper is to compare and analyse the relevant physical property models including BWRS, PR, PRBM, RKS and SRK equations of state, and NRTL-RK model which are crucial numerical process simulation tools. To evaluate the predictive accuracy of the equation of the state for $CO_2-SO_2$ mixture, we compared numerical calculation results with reference experimental data. In addition, optimum binary parameter to consider the interaction of $CO_2$ and $SO_2$ molecules was suggested based on the mean absolute percent error. In conclusion, we suggest the most reliable physical property model with optimized binary parameter in designing the $CO_2-SO_2$ mixture marine geological storage process.

Effect of Nitrogen Impurity on Process Design of $CO_2$ Marine Geological Storage: Evaluation of Equation of State and Optimization of Binary Parameter (질소 불순물이 이산화탄소 해양 지중저장 공정설계에 미치는 영향 평가: 상태방정식의 비교 분석 및 이성분 매개변수 최적화)

  • Huh, Cheol;Kang, Seong-Gil
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.12 no.3
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    • pp.217-226
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    • 2009
  • Marine geological storage of $CO_2$ is regarded as one of the most promising options to response climate change. Marine geological storage of $CO_2$ is to capture $CO_2$ from major point sources, to transport to the storage sites and to store $CO_2$ into the marine geological structure such as deep sea saline aquifer. Up to now, process design for this $CO_2$ marine geological storage has been carried out mainly on pure $CO_2$. Unfortunately the captured $CO_2$ mixture contains many impurities such as $N_2$, $O_2$, Ar, $H_2O$, $SO_x$, $H_2S$. A small amount of impurities can change the thermodynamic properties and then significantly affect the compression, purification and transport processes. In order to design a reliable $CO_2$ marine geological storage system, it is necessary to perform numerical process simulation using thermodynamic equation of state. The purpose of the present paper is to compare and analyse the relevant equations of state including PR, PRBM, RKS and SRK equation of state for $CO_2-N_2$ mixture. To evaluate the predictive accuracy of the equation of the state, we compared numerical calculation results with reference experimental data. In addition, optimum binary parameter to consider the interaction of $CO_2$ and $N_2$ molecules was suggested based on the mean absolute percent error. In conclusion, we suggest the most reliable equation of state and relevant binary parameter in designing the $CO_2-N_2$ mixture marine geological storage process.

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Nutrient Intakes and Physical Activity Self-efficacy of High-rade Elementary School Students according to Obesity Index (초등학교 고학년 아동의 비만도에 따른 영양소 섭취량 및 신체활동 자기효능감)

  • Jang, Hyun-Sook;Hwang, In-Jung
    • Journal of Korean Home Economics Education Association
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    • v.18 no.4 s.42
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    • pp.67-84
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    • 2006
  • This study was carried out to investigate nutrient intake, dietary self-efficacy, and physical activity self-efficacy of elementary school students by obesity index in Gyeongbuk area. The survey was conducted from June 7 to June 18 in 2005. The study was peformed by analyzing a questionnaire answered by 523 elementary school student in 5th and 6th grade. The obesity index was gained by height and weight data. Nutrient intakes was evaluated by 24hr-dietary record. Statistical data analysis were completed using the SPSS 12.0 program. The results were summarized as follows; The result of the body measurement was that 31.7% of underweight group, 45.1% of normal group, 12.8% of overweight group, 10.3% of obese group. 13.9% of underweight group experienced weight control, and 17.5% of the subject respond they will try the weight control in the future. Male students showed significantly higher exercise frequency than female students(p<0.001). Male underweight group and female obese group show the highest exercise frequency. Daily energy intake of the subject showed 80.1% in male students and 87.5% in female students revealed under the recommended dietary allowance(RDA) for Korean. The intake ratio of energy nutrients was identical in male and female of underweight group and obese group, so this showed that intake style was similar in two groups. By investigating through MAR(mean adequacy ratio), underweight group of male students and both normal and overweight group of female students were lowest, while overweight group of male students and underweight group of female students were the highest. Physical activity self-efficacy of male students was higher than female students, and physical activity self-efficacy by obesity index was higher in underweight group of male students and obese group in female.

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Iron Status According to Serum Selenium Concentration and Physique in Young Female Adults (젊은 여성의 혈청 셀레늄 농도 및 체격에 따른 체내 철 수준)

  • Lee, Ok-Hee;Chung, Yong-Sam;Moon, Jong-Wha
    • Journal of Nutrition and Health
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    • v.43 no.2
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    • pp.114-122
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    • 2010
  • Se and Fe are trace minerals acting as antioxidant scavenging free radicals. Iron deficiency is the most frequently reported nutritional deficiency in females. Body iron status are known to be dependent not only upon dietary iron intake, but also upon micro-mineral nutrition and obesity. Antioxidants such as selenium are reported to play an important role on the regulation of erythropoiesis by protecting RBC membrane from antioxidative damage. In this study, iron status in young females and its relationships with selenium status and physique were examined. Serum selenium and iron concentrations were measured by HANARO research reactor using neutron activation analysis method (NAA-method). The proportion with iron deficiency and anemia were 27.1% and 8.6%, respectively in young females, but the proportion with iron deficient anemia was 1.4%. The mean serum selenium level was $12.0\;{\mu}g/dL$ and in normal range in the young women. The study participants were tertiled according to BMI and serum selenium levels. Serum ferritin and iron levels inclined with increasing BMI tertiles. Serum iron and RBC count were higher in middle selenium group than low selenium group. Individuals had significantly lower hematocrit level in the lowest tertile for their serum selenium levels compared with the highest tertile. The serum ferritin level was predicted 25% by BMI and RBC count 26.2% by the serum selenium level and body fat%. In conclusion, this study shows that body iron status in young adult females are influenced by obesity and body selenium status.

College Students' Dietary Behavior, Health-Related Lifestyles and Nutrient Intake Status by Physical Activity Levels using International Physical Activity Questionnaire (IPAQ) in Incheon Area (국제신체활동설문(IPAQ)을 이용한 신체활동도에 따른 인천지역 대학생의 식행동, 건강관련 생활습관 및 식이섭취 조사)

  • Yoo, Jeong-Soon;Chin, Jeong-Hee;Kim, Mi-Jung;Jang, Kyung-Ja
    • Journal of Nutrition and Health
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    • v.41 no.8
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    • pp.818-831
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    • 2008
  • The purpose of this study was to investigate the dietary behavior, health-related lifestyles and nutrient intake status of college students according to physical activity levels. The physical activity levels were measured using the Korean version of the International Physical Activity Questionnaire (IPAQ) short form. The subjects of this study were 438 college students (243 males and 195 females) in Incheon area and were divided by gender and by physical activity levels, which included low, moderate and high physical activity groups. The average age of male and female students were 23.7 and 21.0 years old, respectively. The prevalence of the low physical activity group was 11.5% for males and 30.8% for females and that of the high physical activity group was 38.7% for males and 22.6% for females. According to the criteria for obesity in Asia-Pacific region, 39.1% of the males and 64.1% of the female students investigated were in the normal range of BMI and 30.9% of the males and 4.6% of the female students were in the obesity category. However, percent of body fat in the female students was significantly higher than that of the male students. The soft lean mass of the high physical activity group was higher compared to the other groups. In the low physical activity group, frequency of “eating out” was lower compared to the other groups. The average consumption of energy was 74.4% for males and 80.1% for females of the estimated energy requirement (EER). The mean intakes of vitamin C, vitamin B2, folic acid and Ca were 67.3%, 84%, 52.7% and 36.7% for males and 64.8%, 99.9%, 51.1% and 40.1% for females of recommended intake (RI), respectively. Therefore, it was necessary for obesity prevention as well as health promotion to increase physical activity and to eat an adequate, balanced diet in female college students.