• Title/Summary/Keyword: smooth water

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A Pregnant Smooth Hammerhead Sphyrna zygaena, Collected in the Western Coastal Water, Korea (우리나라 서해 연안에서 잡힌 귀상어 임신개체)

  • Choi, Youn
    • Korean Journal of Ichthyology
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    • v.30 no.3
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    • pp.167-169
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    • 2018
  • A smooth hammerhead, Sphyrna zygaena, was caught from the coastal water of Boryeoung-si, Chungcheongnam-do, Korea in June 13, 2014. The shark had a total of 23 fetuses in its body. There were 12 males and 11 females. The total length of the young sharks ranges from 49.0 cm to 54.7 cm. This collection suggested that western coastal water of Korea is a birth ground of smooth hammerhead, Sphyrna zygaena.

Falling Film Heat Transfer on a Horizontal Single Tube (수평단관 상의 유하액막 열전달)

  • 김동관;김무환
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.7
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    • pp.642-648
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    • 2000
  • Falling film heat transfer analyses with aqueous lithium bromide solution were peformed to investigate the transfer characteristics of the copper tubes. Finned(knurled) tube and a smooth tube were selected as test specimens. Averaged generation fluxes of water and the heat transfer performances(heat flux, heat transfer coefficient) were obtained. The results of this work were compared with the data reported previously. As the film flow rate of the solution increased, the generation fluxes of water decreased for both tubes. The reason is estimated by the fact that the heat transfer resistance with the film thickness increased as the film flow rate increased. The effect of the enlarged surface area at the knurled tube was supposed to be dominant at a small flow rate. The generation fluxes of water increased with the increasing degree of tube wall superheat. Nucleate boiling is supposed to occur at a wall superheat of 20 K for a smooth tube, and at 10 K for a knurled tube. The heat transfer performance of the falling film was superior to pool boiling at a low wall superheat below 10 K for both tubes tested. The knurled tube geometry showed good performance than the smooth tube, and the increased performance was mainly came from the effect of the increased heating surface area.

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Effects of Ponciri Fructus and Aurantii Fructus Immaturus on the Gastric Fundus Motility (위저부 평활근 운동에 대한 국산과 중국산 지실의 효능)

  • Kim, Tae-Wan
    • Journal of Veterinary Clinics
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    • v.30 no.1
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    • pp.27-31
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    • 2013
  • We investigated the effects of Ponciri Fructus (PF) and Aurantii Fructus Immaturus (AI) on the cicular and longitudinal smooth muscle of rat gastric fundus. Methanol extracts of PF (PFM) and AI (AIM), water-fractions (PFW, AIW) and chloroform-fractions (PFC, AIC) of the extracts induced relaxation in the rat fundic circular muscle pre-contracted by U46619. All extracts showed relaxation without significant differences among the extracts. In the longitudinal smooth muscle, PFM and its water fraction, PFW, showed multiphasic effects, fast relaxation and rebound contraction followed by lasting relaxation. AIM and AIW showed diphasic effects, transient contraction followed by lasting relaxation. However, PFC and AIC induced only relaxation in the rat fundic longitudinal muscle contracted by U46619. PFM showed significantly more effective relaxation compared with PFW, AIM and AIW. Hesperidin, flavonoids known as common constituent of PF and AI and it's an aglycon, hesperetin, induced relaxation in both fundic circular and longitudinal smooth muscle pre-contracted by U46619. Poncirin, known as flavonoid content of PF showed also induced relaxation in the both circular and longitudinal smooth muscle pre-contracted by U46619. These results suggest that both PF and AI has relaxing effects on the gastric fundus smooth muscle and its effects might be caused by their flavonoids constituents.

Studies on the Effects of Haengsoyeum (杏蘇飮) Water Extract on the Plasma Cortisol Concentration in the Rabbit and the Contraction of Isolated Guinea Pig Tracheal Smooth Muscle (행소음전탕액(杏蘇飮煎湯液)이 가토혈장(家兎血漿) COTISOL농도(濃度) 및 $PCO_2,\;CO_2$와 GUINEA PIG의 기관지(氣管支) 평활근(平滑筋)에 미치는 영향(影響))

  • Lee, Sueng-Ho
    • The Journal of Internal Korean Medicine
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    • v.13 no.1
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    • pp.143-155
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    • 1992
  • The following results were obtained from the observation on the change of plasma cortisol concentration in the experiment of intravenous administration of Haengsoyeum Water Extract in the rabbit. And the effects of Haengsoyeum extract on the contractile force of the isolated guinea pig trachea smooth muscle. 1. In intravenous administration the plasma cortisol concentration increased significantly about 1 hours after with a does of 0.2 ml/kg. 2. In intravenous administration the plasma cortisol concentration increased significantly about from 1 to 3 hours after with a does of 0.4 ml/kg. 3. The contractile response of the trachea smooth muscle of isolated guinea pig to histamine $10^{-4}\;M$ was significantly inhibited by Haengsoyeum extract. 4. The contractile response of the trachea smooth muscle of isolated guinea pig to acetylcholine $10^{-4}\;M$ was considerably inhibited by Haengsoyeum extract. 5. The contractile response of the trachea smooth muscle of isolated guinea pig to 5-hydroxytryptamine $10^{-4}\;M$ was inhibited by Haengsoyeum extract.

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A Molecular Dynamics Simulation for the Moving Water Droplet on Atomistically Smooth Solid Surface (원자적으로 균일한 평판 위에서 움직이는 물 액적에 대한 분자동역학 시뮬레이션)

  • Hong, Seung-Do;Ha, Man-Yeong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.33 no.8
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    • pp.559-564
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    • 2009
  • The variation in the shape of water droplet moving on atomistically smooth solid surface in the presence of a constant body force is simulated using molecular dynamics simulation. We investigated how the advancing and receding contact angle of the moving water droplet changes on a solid surface having various characteristic energies. From the MD simulation results, we obtained the density profile defined as the number of water molecules at a given position. Then, assuming the water droplet periphery to be a circle, we calculated the contact angles by using a nonlinear fitting of the half-density contour line. The present simulation clearly shows the different profile of the advancing and receding contact angle for these three different interaction potential between the water droplet and the solid surface.

A Study on the Additional Installation of Coastal Wave Buoys in Smooth Water Areas to Prevent Marine Accidents (해양사고 예방을 위한 평수구역 내 파고부이 추가설치 검토)

  • Min-Kyoon Kang;Dong-Il Seol
    • Journal of Navigation and Port Research
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    • v.47 no.6
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    • pp.350-357
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    • 2023
  • Marine accidents frequently occur due to the unreasonable operation of ships excluded from ship departure control during marine special weather warnings within smooth water areas. Coastal wave buoys installed in smooth water areas are major reference indicators for ship departure control and can be seen as being directly connected to the safety of ships navigating smooth water areas and the coast. In this study, the location appropriateness of currently operating coastal wave buoys and additional installation in the smooth water areas were assessed by analyzing coastal marine accidents over the past 30 years (1991-2020), the main wind direction and wind speed of each major trading port, and the GICOMS ship track data in 2018. The study results showed that an additional coastal wave buoy should be installed at each of the major trading ports(Inchon Port, Pohang Port, Ulsan Port, and Busan Port) and that the location of the coastal wave buoy needs to be moved in the case of Busan Port. Based on various data analysis in this study, the suggestion for an additional installation and movement of the coastal wave buoy presented in this study is expected to contribute to improving the reliability of ship departure control and resolving safety blind spots.

Evaluation of the Antioxidant and Antiproliferative Properties of a Hot-water Extract from Gulfweed, Sargassum fulvellum

  • Kim, So Jung;Kang, Mingyeong;Lee, Taek-Kyun
    • Journal of Marine Bioscience and Biotechnology
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    • v.10 no.2
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    • pp.53-61
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    • 2018
  • Sargassum fulvellum (gulfweed) is a widespread seaweed in the coastal areas of northeast Asia. In the present study, we identified the phenolic compounds present in aqueous and ethanolic extracts of S. fulvellum and evaluated their antioxidative properties and their abilities to block cell proliferation using in vitro assays: antioxidant activity was assessed by using a DPPH assay and superoxide anion scavenging activity, anti-tyrosinase activity, and anti-proliferative activity were assessed using MTT and lactate dehydrogenase [LDH] assays in vascular smooth muscle cells. The hot-water ($65^{\circ}C$) extract had a higher phenol content than the ethanolic extract. The hot-water extract showed a statistically significant increase in free radical scavenging activity and a greater ability to reduce proliferation of vascular smooth muscle cells stimulated with platelet-derived growth factor-BB. Taken together, hot-water extracts of S. fulvellum may be an important source of antioxidative and antiproliferative agents.

Wave Run-up and Reflection on Slopes of S-berm Breakwaters Armored with Tetrapods (테트라포드를 이용한 S-berm 경사식 방파제의 처오름과 반사)

  • Ahn, Tae-Jun;Lee, Seung-Hyeob;Cho, Yong-Sik
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.05b
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    • pp.1078-1082
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    • 2005
  • In this study, the run-up height and reflection property on slopes of S-berm and smooth slopes breakwaters are investigated by laboratory experiment. The run-up height analyzed the effect of reflection coefficient, surf similarity parameter. Measured reflection coefficients of smooth slope breakwaters are compared with those of S-berm breakwater with variable widths. In general, measured coefficients of S-berm breakwaters are smaller than those of smooth slope breakwaters.

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Effects of Radix Angelicae Gigantis and Resina Ferulae on the Relaxation of Smooth Muscle and Expression of iNOS (당귀 및 아위가 평활근 이완과 iNOS 발현에 미치는 영향)

  • 김성재;송봉근;이언정;김형균;김중길
    • The Journal of Korean Medicine
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    • v.21 no.2
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    • pp.60-67
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    • 2000
  • Objectives : Radix Angelicae Gigantis(RAG) and Resina Ferulae(RF) have been used in oriental medicine or folk medicine to increase stamina. The aim of this study was the characterization of the mechanism of action of RAG and RF on smooth muscle and macrophages in rats to find new substances for the treatment of erectile dysfunction, cardiovascular diseases and immune dysfunction. Methods : We investigated the effects of the water extracts of RAG and RF on phenylephrine or KCl-contracted rat endothelium-denuded aorta, the production of NO in vascular smooth muscle cell (VSMC) and the production of NO and induction of iNOS in the $IFN-{\gamma}-primed$ RAW 264.7 cells. Results : The water extracts of the RAG and RF showed significant concentration-dependent relaxation effects on phenylephrine or KCl-contracted rat endothelium-denuded aorta. It also reduced the tension of the rat endothelium denuded aorta which was contracted in $Ca^{2+}-free$ media. On the other hand, it increased production of NO in VSMC which was stimulated with $IL-{\beta}$ or $IL-{\beta}$ plus $IFN-{\gamma}$. The water extracts of RAG and RF increased production of NO and induction of iNOS in the $IFN-{\gamma}-primed$ RAW 264.7 cells. Conclusions : According to the above results, the water extracts of RAG and RF relaxed the smooth muscle effectively and increased the production of NO in VSMC and macrophages. So, these herbs can be applied to erectile dysfunction, hypertension, angina pectoris, artherosclerosis and a defense defect for virus or microbe.

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Evaporation of Water in an Aqueous Lithium Bromide Solution flowing over a Horizontal Tube

  • Kim, Dong-Kwan;Kim, Moo-Hwan
    • International Journal of Air-Conditioning and Refrigeration
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    • v.9 no.3
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    • pp.57-62
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    • 2001
  • Falling film heat transfer analyses with aqueous lithium bromide solution were performed to investigate the transfer characteristics of the copper tubes. Finned (knurled) tube and a smooth tube were selected as test specimens. Averaged generation fluxes of water and the heat flux were obtained. As the film flow rate of the solution increased, the generation fluxes of water decreased for both tubes due to the fact that the heat transfer resistance increased with the film thickness. The effect of the enlarged surface area at the knurled tube was supposed to be dominant at a small flow rate. The generation fluxes of water increased with the increasing degree of tube wall superheat. Nucleate boiling is supposed to occur at a wall superheat of 20K for a smooth tube, and at 10K for a knurled tube. The increased performance of the knurled tube was supposed to mainly come from the effect of the increased heating surface area.

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