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A Study on Efficient Capacity Control of a Marine Pump with the Variation of Sea Water Temperature (선박용 펌프의 해수온도 변화에 따른 효율적인 유량제어에 관한 연구)

  • Choi, Sang-Bom;Im, Myeong-Hwan
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.6
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    • pp.788-793
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    • 2014
  • In this study, the electrical power consumption saving effect is studied through installing an inverter which is able to control the R.P.M. of marine sea water pump by effective flow control. The study looks at how sea water pump's flow control influences on the system without the Marine Growths Protection System(MGPS). Auxiliary sea water pump and refrigerator sea water pump in training ships, which are always operated not only in harbor but also in navigation, was used in the experiment and the experiment was conducted by dividing into harbor and navigation. As a result of research, in the case the sea water temperature is under $18^{\circ}C$, the operation was possible with a 58.3 % decrease in pump R.P.M. and electric power consumption was saved by 50 %. In spite of the sea water temperature increasing upto $34^{\circ}C$, pump R.P.M. at 91.6 % was sufficient to operate with a 20 % electric power consumption saving effect. In the pipelines without MGPS, lowering R.P.M. along with lowering pressure results in the attachment of various marine growths.

Comparison of Radiation Adaptive Responses in Peripheral Lymphocytes of Patients Undergoing Tc-99m MDP and Tc-99m DTPA Scintigraphies (Tc-99m MDP와 Tc-99m DTPA 신티그라피를 시행한 환자의 말초혈액 림프구에서 유도되는 방사선 적응반응의 비교)

  • Bom, Hee-Seung;Li, Ming-Hao;Min, Jung-Jun;Kwon, An-Sung;Kim, Ji-Yeul
    • The Korean Journal of Nuclear Medicine
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    • v.34 no.3
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    • pp.252-259
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    • 2000
  • Purpose: The purpose of this study was to compare the radiation adaptive response (RAR) in peripheral lymphocytes (PL) of patients induced by Tc-99m MDP and Tc-99m DTPA scintigraphies. Materials and Methods: Lymphocytes from 45 patients (25 males, 20 females, mean age $44{\pm}18$ years) were collected before and after scintigraphies using 740 MBq Tc-99m MDP (n=22) or Tc-99m DTPA (n=23). Lymphocytes from 20 controls (12 males, 8 females, mean age $43{\pm}7$ years) were also collected. They were exposed to challenge dose of 2 Gy ${\gamma}-rays$ using a Cs-137 cell irradiator Number of ring-form (R) and dicentric (D) chromosomes was counted under the light microscope. From them a representative score, Ydr, was calculated as Ydr=(D+R)/cells. Adaptation index (AI) was defined as difference of Ydr between unconditioned and conditioned lymphocytes. Ydr was also measured after an administration of cycloheximide (CHM), a protein synthesis inhibitor, before challenge dose. Results: RAR was induced in both groups of patients. CHM abolished the adaptive response in both groups. AI of Tc-99m MDP group was significantly higher than that of Tc-99m BTPA group. Conclusion: Tc-99m MDP induced RAR was more prominent than those induced by Tc-99m DTPA.

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The Limnological Survey and Phosphorus Loading of Lake Hoengsung (횡성호의 육수학적 조사와 인부하)

  • Kwon, Sang-Yong;Kim, Bom-Chul;Heo, Woo-Myung
    • Korean Journal of Ecology and Environment
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    • v.37 no.4 s.109
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    • pp.411-422
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    • 2004
  • A limnological survey was conducted in a reservoir, Lake Hoengsung located in Kangwondo, Korea, from July 2000 to September 2001 on the monthly basis. Phosphorus loading from the watershed was estimated by measuring total phosphorus concentration in the main tributary. Secchi disc transparency, epilimnetic (0-5 m) turbidity, chlorophyll a (Chl-a), total phosphorus (TP), total nitrogen(TN) and silica concentration were in the range of 0.9-3.5 m, 0.1-8.5 NTU, 0.3-32.4 mgChl $m^{-3}$, 5-46 mgP $m^{-3}$, 0.83-3.55 mgN $L^{-1}$ and 0.5-9.6 mgSi $L^{-1}$, respectively. Green algae and cyanobacteria dominated phytoplankton community in warm seasons, from July through October, 2000. In July a green alga (Scenedesmus sp.) was dominant with a maximum cell density of 10,480 cells mL. Cyanobacteria (Microcystics sp.) dominated in August and September with cell density of 3,492 and 295 cells mL ,respectively. Species diversity of phytoplankton was highest (2.22) in July. The trophic state of the reservoir can be classified as eutrophic on the basis of TP, Chl-a, and Secchi disc transparency. Because TP concentration was high in flood period, most of phosphorus loading was concentrated in rainy season. TP loading was calculated by multiplying TP and flow rate. The dam managing company measured inflow rate of the reservoir daily, while TP was measured by weekly surveys. TP of unmeasured days was estimated from the empirical relationship of TP and the flow rate of the main tributary; $TP=5.59Q^{0.45}\;(R^2=0.47)$. Annual TP loading was calculated to be 4.45 tP $yr^{-1}$, and the areal P loading was 0.77 gP $m^{-2}\;yr^{-1}$ which is similar to the critical P loading for eutrophication by Vollenweider's phosphorus model, 0.72 gP $m^{-2}\;yr^{-1}$.

The Usefulness of Tc-99m MIBI SPECT in the Localization and the Assessment of Radiotherapy in Non-Small Cell Lung Cancer (비소세포 폐암의 국소화 및 방사선치료 판정에 있어 Tc-99m MIBI SPECT의 유용성)

  • Bom, Hee-Seung;Song, Ho-Chun;Kim, Ji-Yeul;Nam, Taek-Keum;Ahn, Sung-Ja;Chung, Woong-Ki;Nah, Byung-Sik
    • The Korean Journal of Nuclear Medicine
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    • v.28 no.2
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    • pp.186-191
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    • 1994
  • Tc-99m MIBI, a lipophilic cation, was reported as a useful agent for localization of lung cancer. The effect of radiation therapy on the uptake of Tc-99m MIBI in lung cancer, however, was not well evaluated. The aim of the present study was to elucidate the usefulness of Tc-99m MIBI SPECT in the localization and the assessment of radiotherapy in non-small cell lung cancer. Twenty patients(19 males and 1 female, mean age 59, 16 squamous cell ca and 4 adenoca) were studied with Tc-99m MIBI SPECT before radiation therapy. Eleven patients(10 males and 1 female, mean age 59, 8 squamous cell ca and 3 adenoca) were repeated the study 1 month after the completion of radiation therapy(mean dose 6453cGy). All patients showed positive uptakes of Tc-99m MIBI in their tumors. One patient showed a hot uptake in atelectatic area. There was no difference of Tc-99m MIBI uptakes between squamous cell ca and adenoca either on planar or tomographic images. Tc-99m MIBI uptake ratios of squamous cell ca and adenoca were $1.50{\pm}0.16$ and $1.45{\pm}0.15$ on planar images, and $2.73{\pm}0.46$ and $2.54{\pm}0.37$ on tomographic images, respectively. The concordance between radiological change(chest x-ray and CT) and change of Tc-99m MIBI uptakes was 9/11 (81.8% ). In conclusion, Tc-99m MIBI SPECT was useful in the localization of tumor and the assessment of radiation therapy in non-small cell lung cancer.

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Dynamics of Cyanobacterial Toxins in the Downstream River of Lake Suwa (Suwa호 하류하천에서의 남조류 독소의 동태)

  • Kim, Bom-Chul;Park, Ho-Dong;Katagami, Yukimi;Hwang, Soon-Jin;Kim, Ho-Sub
    • Korean Journal of Ecology and Environment
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    • v.34 no.1 s.93
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    • pp.45-53
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    • 2001
  • Transport of cyanobacterial toxins (microcystin-LR, -RR, -YR) were assessed from a eutrophic lake, Lake Suwa, through the outflowing river, the Tenryu River, and its irrigation channel branch. Temporal variation of phytoplankton species composition in the river coincided with those of the lake; Microcystis ichthyoblabe dominated from June to July, and M. viridis dominated from August to September. When cyanobacterial bloom occurred, microcystins were continuously detected at the concentration of $0.3{\sim}3.2\;{\mu}g/l$ even at 32 km downstream. The change of the content of three microcystin variants were related both with the total cell density of Microcystis and with the change of Microcystis species composition. When Microcystis ichthyoblabe dominated during July, only microcystin-RR (MC-RR) and -LR (MC-LR) were detected, while when Microcystis viridis dominated between August and October, microcystin-RR,-YR (MC -YR) and -LR were detected. Along 29 km flowing distance (flow time 11 hours) between site 2 and site 5 in the Tenryu River, cyanobacterial density and microcystin concentration were reduced by 73% and 72%, respectively, which is mostly contributed by the dilution effect of tributary waters (61% and 57%, respectively) . In the artificial irrigation channel microcystins and cyanobacterial cells were decreased less than in the natural river. The results indicate that cyanobacterial toxins can be transported far downstream without much removal and give hazards to water usage in downstream of eutrophic lakes with cyanobacterial blooms.

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Effects of a variety of treatments affecting Chinese cabbage protoplast culture, and plant regeneration from protoplast-derived callus (배추 원형질체 배양에 미치는 다양한 처리의 효과와 원형질체 유래 캘러스로부터 신초 재분화)

  • Han, Jeung-Sul;Yoon, Moo-Kyeong;Jeong, Mi-Hye
    • Journal of Plant Biotechnology
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    • v.35 no.3
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    • pp.235-243
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    • 2008
  • Here we describe a procedure for Chinese cabbage protoplast culture and effects of various treatments. Chinese cabbage protoplasts were isolated from different parts of young seedlings as using an enzyme mixture, of which yield was maximized in seven hours around after digestion. The highest rate of initial cell division followed by micro-callus formation was obtained in the medium with 1.0 mg/L 2,4-D, 0.5 mg/L NAA, and 1.0 mg/L BA when the cotyledon-derived protoplasts were cultured. Initiation of cell division and micro-callus proliferation significantly depended upon Chinese cabbage genotype under a same culture circumstances. The micro-calli developed from cotyledon tissue of Norang-Bom cultivar successfully grew toward callus colonies on the solidified medium with 0.2 mg/L zeatin and 0.1 mM spermidine. The callus colonies generated de novo shoots at the maximum frequency of 4.3% on the medium with 5.0 mg/L BA and 1.0 mg/L NM. Our results might be helpful for further studies to enhance the regeneration efficiency in Chinese cabbage protoplast culture.

Scintigraphic Assessment of Myocardial Viability (신티그라피에 의한 심근생존능 평가)

  • Bom, Hee-Seung
    • The Korean Journal of Nuclear Medicine
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    • v.27 no.2
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    • pp.155-160
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    • 1993
  • The identification of viable myocardium in patients with coronary artery disease and left ventricular dysfunction is an issue of increasing clinical relavance in the current era of myocardial revascularization. There are at least two forms of reversible myocardial dysfunction. Early reperfusion does not always lead to immediate functional improvement; rather, the return of contractility in tissue salvaged by reperfusion is delayed for hours, days or even weeks, a phenomenon that has been termed "stunned myocardium". Some patients with coronary artery disease show myocardial dysfunction at rest which are associated with reduced perfusion, and which disappear after revascularization; this phenomenon has been termed "hibernating myocardium". Recently, cardiac imaging techniques that evaluate myocardial viability on the basis of perfusion-contraction mismatch and inotropic reserve have gained substantial popularity and clinical success. This review focus on the application of $^{201}TI$ and $^{99m}Tc-MIBI$ to address myocardial viability in patients with hibernating and stunned myocardium. It is clear that 4-hour redistribution images of $^{201}TI$ underestimate ischemia and overestimate scar. Delayed imaging and reinjection imaging have been developed for the assessment of viability. Among many protocols suggested, stress-redistribution-reinjection imaging gained most popularity. Although $^{99m}Tc-MIBI$ could identify myocardial viability, $^{201}TI$ reinjection technique was regarded as superior to it. In conclusion, $^{201}TI$ stress, 4-hr rest redistribution, and reinjection imaging technique may be the most preferable method for evaluation of myocardial viability.

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Primary Productivity of Phytoplankton at the Eutrophic down Reach of a Regulated River (the Han River, Korea) (부영양한 한강하류수역에서 식물플랑크톤의 1차생산)

  • Nam, Kung-Hyun;Hwang, Gil-Son;Kim, Kap-Soo;Kim, Bom-Chul
    • Korean Journal of Ecology and Environment
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    • v.34 no.4 s.96
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    • pp.267-276
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    • 2001
  • The downstream reach of the Han River adjoining Seoul in Korea was the upper boundary of an estuary where tidal effect on the flow rate could be exerted. According to the comprehensive river regulation project, the river was channelize dand impounded by two overflow dams, which provided favorable condition for algal growth in this sewage polluted eutrophic reach. In this study primary productivity of phytoplankton was measured in the down reach and the autochthonous and allochthonous organic carbon loadings were estimated. Primary production of phytoplankton measured by C-14 uptake and P-I model method ranged from 140 to $4,890\;mgC\;m^{-2}\;d^{-1}$ (median value $1,865\;mgC\;m^{-2}\;d^{-1}$) showing the level of eutrophic lakes. Phytoplankton density that varied according to water flow rate was highest in spring. Allochthonous organic carbon loading was dominated by sewage input through tributaries in most of days except flood flow period. The average proportion of autochthonous carbon generation by phytoplankton was 40.9%, which is very high proportion for a lotic habitat.

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Phosphorus Cycle in a Deep Reservoir in Asian Monsoon Are3 (Lake Soyang, Korea) and the Modeling with a 2-D Hydrodynamic Water Quality Model [CE-QUAL-W2] (아시아 몬순지역의 대형댐(소양호)에서의 인순환과 2차원모델의 적용)

  • Kim, Yoon-Hee;Kim, Bom-Chul
    • Korean Journal of Ecology and Environment
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    • v.37 no.2 s.107
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    • pp.205-212
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    • 2004
  • Phosphorus cycle was studied in a deep stratified reservoir in summer monsoon area (Lake Soyang, Korea) by surveying phosphorus input from the watershed and the movement of phosphorus within the reservoir. And the spatial and temporal distribution of phosphorus was modeled with a 2-dimensional water quality model (CE-QUAL-W2), Phosphorus loading was calculated by measuring TP in the main inflowing river (the Soyang River) accounting for 90% of watershed discharge. TP of the Soyang River showed a large daily variation with the flow rate. High phosphorus loading occurred during a few episodic storm runoff laden with suspended sediments and phosphorus. Because storm runoff water on rainy days have lower temperature, it plunges into a depth of same temperature (usually below 20m depth), forming an intermediate turbidity layer with a thickness of 20 ${\sim}$ 30 m. Because of stable thermal stratification in summer the intermediate layer water of high phosphorus content was discharged from the dam through a mid-depth outlet without diffusing into epilimnion. The movement of runoff water within the reservoir, and the subsequent distribution of phosphorus were well simulated by the water quality model showing a good accuracy. The major parameter for the calibration of phosphorus cycle was a settling velocity of detritus, which was calibrated to be 0.75 m ${\cdot}$ $day^{-1}$. It is concluded that the model can be a good simulator of limnological phenomena in reservoirs of summer monsoon area.

The Effects of Pilates Exercise on Static and Dynamic Balance in the Elderly

  • Park, Ji-Hye;Lee, Joong-Sook;Yang, Jeong-Ok;Lee, Bom-Jin;Bae, Kang-Ho;Shin, Jin-Hyung
    • Korean Journal of Applied Biomechanics
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    • v.26 no.4
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    • pp.397-405
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    • 2016
  • Objective: Pilates is a low/mid-intensity exercise that can be easily performed by elderly individuals as it is an individual body-oriented exercise. It is also a cardio workout that can be performed anywhere to develop strength and flexibility. Therefore, we investigated the effects of 8 week Pilates program on the balancing ability of elderly individuals. Method: The research participants were selected from elderly residents in B city. Ten individuals voluntarily signed an agreement to undergo free measurements as well as to participate in the workout program. (Height: $157.1{\pm}11.9cm$, Weight: $61.7{\pm}8.0kg$). The Pilates exercise was performed 60 minutes a day, three times a week for a total of eight weeks. The measurement variables used to test balance were the vestibular test, 5 m habitual and maximum walk test and 3 m tandem walk test. A series of paired t-test were conducted using IBM SPSS Statistics 23.0 to analyze all the research data collected in order to determine the balance ability of the participants before and after the Pilates program. Additionally, the statistically significant level for all analysis was set to ${\alpha}=.05$. Results: In the vestibular test, some meaningful changes were observed in the length envelope area (ENV) while standing on one foot, but there were no significant differences in the ENV, rectangle(REC), root mean square, and total length. Results also revealed that statistically significant differences existed in the 5 m habitual and maximum walk test, as well as the 3 m tandem walk test. Conclusion: To summarize the findings, the 8 week Pilates program employed in this study significantly improved the dynamic balance of the elderly participants. Thus, elderly individuals that frequent perform Pilates are expected to enjoy positive benefits such as increased balance and fewer falling accidents.