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Chronic Effect Exposed to Carbon Dioxide in Benthic Environment with Marine Invertebrates Copepod(Tisbe sp.) and Amphipod(Monocorophium acherusicum) (저서환경에서 이산화탄소 노출에 따른 국내산 해산무척추동물 요각류(Tisbe sp.)와 단각류(Monocorophium acherusicum)의 만성영향)

  • Moon, Seong-Dae;Choi, Tae Seob;Sung, Chan-Gyoung;Lee, Jung-Suk;Park, Young-Gyu;Kang, Seong-Gil
    • Journal of Environmental Science International
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    • v.22 no.3
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    • pp.359-369
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    • 2013
  • Chronic effects such as reproduction and population dynamics with elevated $CO_2$ concentration were evaluated using two representative marine benthic species, copepod (Tisbe sp.) and amphipod (Monocorophium acherusicum) adopting long-term exposure. Juvenile copepod and amphipod individuals were cultivated in the seawater equilibrated with control air (0.395 mmol $CO_2$/air mol) and high $CO_2$ air having 0.998, to 3.03, 10.3, and 30.1 mmol $CO_2$/air mol during 20 and 46 days, respectively. After the exposure period, the number of benthic invertebrate was counted with separate larval and juvenile stage such as naupliar, copepodid and adult for copepod, or neonate and adult for amphipod, respectively. The individual number of both test species at each life-stage was significantly decreased in seawater with 10.3 mmol $CO_2$/air mol or higher. Recently, the technology of marine $CO_2$ sequestration has been developed for the reduction of $CO_2$ emission, which may cause climate change. However, under various scenarios of $CO_2$ leaks during the injection process or sequestrated $CO_2$ in marine geological structure, the potential risk to organism including various invertebrates can be expected to exposure. So the results of this study suggested that the detailed consideration on the adverse effect with marine ecosystem can be prerequisite for the marine $CO_2$ sequestration projects.

Mixed Convection Heat Transfer in a Rectangular Enclosure with Various Outlets (좁은 환기구를 가진 사각공간에서의 혼합대류 열전달)

  • Lee, C.J.;Chung, H.S.;Kwon, S.S.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.7 no.2
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    • pp.207-216
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    • 1995
  • Flow and heat transfer characteristics of mixed convection heat transfer in a rectangular en-closure with various outlets are numerically investigated. The parameters considered here include Reynolds number, Grashof number and the position of outlet. The results show streamlines, isotherms, Nusselt numbers, velocity and temperature distributions. It has been shown that as Reynolds number increases, the size of cell decreases at Re$\leq$100 and increases at Re>100 for $Gr=10^4$. There is a minimum size of cells at Re=100, $Gr=10^4$. The maximum mean Nusselt number occurs at Re=400, $Gr=10^4$ and one right outlet. The mean Nusselt numbers can be formulated by the correlation equation $Nu=C{\cdot}Gr^a{\cdot}Re^b$.

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A COMPARATIVE STUDY OF TWO AND THREE DIMENSIONAL LOW REYNOLDS NUMBER FLOW (2차원 및 3차원 저레이놀즈수 유동 해석 비교 연구)

  • Lee, Jae-Hun;Jung, Kyoung-Jin;Lee, Kil-Tae;Kang, In-Mo
    • 한국전산유체공학회:학술대회논문집
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    • 2009.11a
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    • pp.3-7
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    • 2009
  • In this study, two and three dimensional low Reynolds number flows are compared. For the two dimensional flow, an airfoil was considered and for the three dimensional low wing and full-body aircraft were considered. Because a flight condition of the aircraft is in a low Reynolds number flow, itl requires reflecting flow transition. In the two dimensional analysis, transition is predicted using en method. In the three dimensional flow, the effect of transition is included using k-w SST turbulence models.

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Influence of the application of Tithonia diversifolia and phosphate rocks on the performances of rainfed rice

  • Rusaati, Butoto Imani wa;Kang, Jun-Won;Gendusa, Patience Arusi;Bisimwa, Pacifique Bulakali;Kasali, Joseph Lumande;Rolly, Nkulu Kabange;Park, Joowon;Rehema, Esther Matendo;Ndabaga, Cephas Masumbuko;Kaboyi, Gentil Iragi;Nankafu, Orleanne Nangalire;Chirimwami, Anastasie Bahati
    • Korean Journal of Agricultural Science
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    • v.47 no.3
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    • pp.403-414
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    • 2020
  • Gradient concentrations of Tithonia diversifolia green leaves and phosphate rocks were used to investigate their contributions as a fertilizer to the yield and quality improvement of a rainfed rice cultivar. Six treatments were compared: (1) T0, no fertilization (control); (2) T1, 1.28 g of phosphate rocks; (3) T2, 250 g of organic matter; (4) T3, 500 g of organic matter; (5) T4, 250 g of organic matter + 1.28 g of phosphate rocks; (6) T5, 500 g of organic matter + 1.28 g of phosphate rocks. The results showed that the germination percentage recorded 15 days after sowing varied from 58 - 76% between T0 and T5. The number of panicles ranged between 2 (T0) to 6.3 (T5). Moreover, the recorded length of the panicles ranged between 7.5 (T1) to 15.8 cm (T2), and the number of grains per panicle ranged between 25.5 (T1) to 273.5 (T3). The plant height was significantly increased in the T5 (79.27 cm) group compared to the T1 (33.63 cm) and control treatment (T0) (40.08 cm) groups. Although the plant height in the T2, T3, and T4 groups was slightly lower than the T5 group, the difference was not statistically significant. The average of the grain number per plant was high in the T3 (273.6 grains) group compared to the T1 and T0 (25.5 and 32.8 grains) groups, respectively. These results suggest that the combination of T. diversifolia leaves and phosphate rocks as a natural fertilizer would be beneficial when integrated into soil fertility management strategies and would contribute to improving crop yield and quality.

The Outcome of Nutrition Support of Surgery Patients with Hypermetabolic Severity by Total Parenteral Nutrition and Enteral Nutrition and Biochemical Data (경장영양과 중시정맥영양을 공급받는 외과계 수술 환자의 과대사 정도에 따른 영양 섭취량 및 생화학적 검사 결과)

  • Rha Mi-Yong;Kim Eun-Mi;Cho Young-Y.;Seo Jeong-Meen;Choi Hay-Mie
    • Korean Journal of Community Nutrition
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    • v.11 no.2
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    • pp.289-297
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    • 2006
  • This study evaluated the nutrition intake and changes in laboratory data of surgery patients with hypermetabolic severity on nutrition support. From January 2002 to September 2002, 66 hospitalized surgery patients who had received enteral nutrition (EN, n=19) and total parenteral nutrition (TPN, n=47) for more than 7 days were prospectively and retrospectively recruited. The laboratory data was examined pre-operatively, and on the post-operative 1, 3, 7 day and at the time of discharge. The characteristics of the patients were examined for the hypermetabolic severity, The hypermetabolic scores were determined by high fever ($>38^{\circ}C$), rapid breathing (>30 breaths/min), rapid pulse rate (>100 beats/min) , leukocytosis ($WBC>12,000/{\mu}l$), leukocytopenia ($WBC>3,000/{\mu}l$), status of infection, inflammatory bowel disease, surgery and trauma. The scores for the hypermetabolic status were divided into three groups (mild 0-10, moderate 11-40, severe>41). According to the results of the study, 38.3% (n=23), 45.4% (n=30) and 19.6% (n=13) were in the mild, moderate, and severe groups, respectively. There was a decrease in the serum albumin level and weight loss according to the hypermetabolic severity. However, the white blood cells (WBC), fasting blood sugar (FBS), c-reactive protein (CRP), total bilirubin, GOT, and GPT increased. The nutritional intake was TPN (32.5 kcal/kg, protein 1.2 g/kg, fat 0.25 g/kg), EN (28.1 kcal/kg, protein 1.0 g/kg, fat 1.01 g/kg). The serum albumin, hemoglobin and cholesterol were higher in the EN group than in the TPN group. But the FBS, total bilirubin, GOT and GPT were higher in the TPN group than the EN group. In conclusion, there was a negative correlation between the changes in the laboratory data and the hypermetabolic severity. There was an increase in the number of metabolic complications in the TPN group.

Evaluation of accuracy for measurement of Dioxins (PCDDs/PCDFs) by using certified reference material (CRM) (인증표준물질(Certified reference materials, CRM)을 이용한 이옥신류(PCDDs/PCDFs) 측정의 정확도 평가)

  • Youn, Yeu Young;Park, Deok Hie;Lim, Young Hee;Cho, Hye Sung
    • Analytical Science and Technology
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    • v.22 no.5
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    • pp.376-385
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    • 2009
  • In our study, the accuracy for measurement of seventeen 2,3,7,8-substituted PCDDs/PCDFs in certified reference material (CRM) which is the sample of homogeneous sediment matrix taken from an area known to have significant chemical contamination, particularly PCBs (polychlorinated biphenyls), was evaluated. Though the methodology in this study followed the official method of unintentionally produced persistent organic pollutants (UPOPs) announced by the Ministry of Environment of the Republic of Korea in 2007, there were slight changes using additional purification step by activated carbon column because the interferences of sample were not sufficiently removed when only multi-silica column and alumina column have been used for purification. The |En| number proposed by the Korea Research Institute of Standards and Science was used for a valuation basis of the accuracy. The |En| numbers of seventeen 2,3,7,8-substituted PCDDs/PCDFs have been indicated as 1 and below, they were decided "Pass" in this test, when DB-5MS column and SP-2331 column were used together. Because 1,2,3,7,8-PeCDD and #169-HxCB were not separated on DB-5MS column, the ions of 1,2,3,7,8-PeCDD were selected at M/M+2 instead of M+2/M+4 suggested by EPA 1613. It is possible to distinguish them in HRGC/HRMS analysis.

Development of the KOBAS2 for monitoring the health status of KOMPSAT-2

  • Koo, In-Hoi;Lee, Myeong-Shin;Ahn, Sang-Il;Kim, En-Kyu
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.824-826
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    • 2006
  • The number of satellite under operation is being on the increase, however, because the number of operator is limited the reliable control system is necessary for stable mission operation. Especially it is necessary that error event indication such as colour or sound should be displayed with high reliability for intuitional monitoring. The limit range of KOBAS2 provides realistic value that is defined with in-orbit value and related document. It makes it possible for operator to monitor a number of telemetry data easily through single screen system instead of monitoring each mnemonics. The development and operation experience of KOBAS2 will contribute to the development of the evolved automatic telemetry monitoring system for future mission.

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Evaluation of the Effects of the Longitudinal Baffle on Settling Efficiency within Rectangular-shaped Sedimentation Basin (장방형 침전지내 도류벽의 침전효율에 대한 영향 평가)

  • Park, No-Suk;Kim, Seong-Su;Seo, In-Seok;Min, Kyong-En
    • Journal of Korean Society of Water and Wastewater
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    • v.23 no.5
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    • pp.573-581
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    • 2009
  • In the case that the average velocity within rectangular-shaped sedimentation basin is less than 1.5cm/sec, and Froude number less than $10^{-6}$, it can not be expected that the longitudinal baffle improves the sedimentation efficiency. Also, since relatively lower velocity increases the effect of geostrophic body force, asymmetric flow pattern on a plane occurs within the basin. From the results of CFD (Computational Fluid Dynamics) simulation, in the case that the highest velocity within rectangular-shaped sedimentation basin is over 1.5cm/sec, and Froude number over $10^{-6}$, it can be expected that the longitudinal baffle installed within rectangular-shaped sedimentation basin improves the sedimentation efficiency.

Procedure for improving dynamic operability of chemical processes

  • Kwon, Youngwoon;Chang, Tae-Suk;Yoon, En-Sup
    • 제어로봇시스템학회:학술대회논문집
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    • 1995.10a
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    • pp.332-335
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    • 1995
  • A simple and effective method for improving Euclidean norm condition number for chemical processing system is presented. The singular value sensitivities of Freudenberg et al. (1982) is used to estimate the behavior of singular values of process transfer function matrix when design parameter is changed, then the condition number can be calculated straightforwardly. The method requires explicit dependencies of each transfer function matrix elements on design parameters. These dependencies can be obtained either by symbolic differentiation in the form of explicit function of design parameters, or by numerical perturbation studies for units with large and complicated models. Gerschgorin-type lower bound for minimum singular value is introduced to detect the large divergencies near singular point due to linearity of sensitivities. The case studies are performed to show the efficiency of the proposed method.

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