• Title/Summary/Keyword: Control of the Sea

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Sensitivity Study of Simulated Sea-Ice Concentration and Thickness Using a Global Sea-Ice Model (CICE) (전구 해빙모델(CICE)을 이용한 해빙 농도와 해빙 두께 민감도 비교)

  • Lee, Su-Bong;Ahn, Joong-Bae
    • Atmosphere
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    • v.24 no.4
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    • pp.555-563
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    • 2014
  • The impacts of dynamic and thermodynamic schemes used in the Community Ice CodE (CICE), the Los Alamos sea ice model, on sea ice concentration, extent and thickness over the Arctic and Antarctic regions are evaluated. Using the six dynamic and thermodynamic schemes such as sea ice strength scheme, conductivity scheme, albedo type, advection scheme, shortwave radiation method, and sea ice thickness distribution approximation, the sensitivity experiments are conducted. It is compared with a control experiment, which is based on the fixed atmospheric and oceanic forcing. For sea ice concentration and extent, it is found that there are remarkable differences between each sensitivity experiment and the control run over the Arctic and Antarctic especially in summer. In contrast, there are little seasonal variations between the experiments for sea ice thickness. In summer, the change of the albedo type has the biggest influence on the Arctic sea ice concentration, and the Antarctic sea ice concentration has a greater sensitivity to not only the albedo type but also advection scheme. The Arctic sea ice thickness is significantly affected by the albedo type and shortwave radiation method, while the Antarctic sea ice thickness is more sensitive to sea ice strength scheme and advection scheme.

Effect of Supplementation of Dietary Sea Tangle on the Renal Oxidative Stress in Diabetic Rats (식이 다시마의 섭취가 당뇨 쥐 신장의 산화적 스트레스 및 당뇨성 병변에 미치는 영향)

  • Park, Min-Young;Kim, Kyung-Hee;Jeong, Kyu-Shik;Kim, Hyeon-A
    • Journal of the Korean Society of Food Culture
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    • v.22 no.1
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    • pp.140-148
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    • 2007
  • Diabetic nephropathy has been increasing, although blood glucose and blood pressure can be controlled by angiotensin converting enzyme(ACE) or advanced glycosylation end products(AGE) inhibitors in the diabetic patients. We investigated the effect of dietary supplementation of sea tangle on the blood glucose, and pathological scoring of diabetic kidneys in the streptozotocin(STZ) induced diabetic rats. Male Sprague-Dawley rats were divided into normal rats fed control diet and diabetic rats fed control diet or control diet supplemented with powder or oater extract of sea tangle. Diabetes was induced by a single injection of STZ(60mg/kg, ip) in citrate buffer. The animals were fed the experimental diet and water for 13 weeks. Dietary supplementation of sea tangle decreased blood glucose in the diabetic rats. However, dietary supplementation of sea tangle did not affect the antioxidant enzyme activities, MDA content and pathology of diabetic kidneys. These results indicate that decreased blood glucose by sea tangle could not delay the progression of diabetic kidney disease.

Status of Observation Data at Ieodo Ocean Research Station for Sea Level Study

  • Han, MyeongHee
    • Journal of the Korean earth science society
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    • v.41 no.4
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    • pp.323-343
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    • 2020
  • Observation data measured at Ieodo Ocean Research Station (IORS) have been utilized in oceanographic and atmospheric studies since 2003. Sea level data observed at the IORS have not been paid attention as compared with many other variables such as aerosol, radiation, turbulent flux, wind, wave, fog, temperature, and salinity. Total sea level rises at the IORS (5.6 mm yr-1) from both satellite and tide-gauge observations were higher than those in the northeast Asian marginal seas (5.4 mm yr-1) and the world (4.6 mm yr-1) from satellite observation from 2009 to 2018. The rates of thermosteric, halosteric, and steric sea level rises were 2.7-4.8, -0.7-2.6, 2.3-7.4 mm yr-1 from four different calculating methods using observations. The rising rate of the steric sea level was higher than that of the total sea level in the case with additional data quality control. Calculating the non-steric sea level was not found to yield meaningful results, despite the ability to calculate non-steric sea level by simply subtracting the steric sea level from total sea level. This uncertainty did not arise from the data analysis but from a lack of good data, even though tide, temperature, and salinity data were quality controlled two times by Korea Hydrographic and Oceanography Agency. The status of the IORS data suggests that the maintenance management of observation systems, equipment, and data quality control should be improved to facilitate data use from the IORS.

Effect of Hypersonic Missiles on Maritime Strategy: Focus on Securing and Exploiting Sea Control (극초음속 미사일이 해양전략에 미치는 영향: 해양통제의 확보와 행사를 중심으로)

  • Cho, Seongjin
    • Maritime Security
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    • v.1 no.1
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    • pp.241-271
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    • 2020
  • The military technology currently receiving the most attention is the hypersonic missile. hypersonic is faster than the speed of sound or Mach 5+. The vast majority of the ballistic missiles that it inspired achieved hypersonic speeds as they fell from the sky. Rather than speed, today's renewed attention to hypersonic weapons owes to developments that enable controlled flight. These new systems have two sub-varieties: hypersonic glide vehicles and hypersonic cruise missiles. Hypersonic weapons could challenge detection and defense due to their speed, maneuverability, and low altitude of flight. The fundamental question of this study is: 'What effect will the hypersonic missile have on the maritime strategy?' It is quite prudent to analyze and predict the impact of technology in the development stage on strategy in advance. However, strategy is essential because it affect future force construction. hypersonic missiles act as a limiting factor in securing sea control. The high speed and powerful destructive power of the hypersonic missile are not only difficult to intercept, but it also causes massive ship damage at a single shot. As a result, it is analyzed that the Securing sea control will be as difficult as the capacity of sea denial will be improved geographically and qualitatively. In addition, the concept of Fortress Fleet, which was criticized for its passive strategy in the past, could be reborn in a modern era. There are maritime power projection/defence, SLOC attack/defence in exploiting sea control. The effects of hypersonic missiles on exploiting sea control could be seen as both limiting and opportunity factors.

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Dietary Supplementation of Sea Tangle (Laminaria japonica) Improves Blood Glucose and Lipid Metabolism in the Streptozotocin-induced Diabetic Rats

  • Park, Min-Young;Kim, Eun;Kim, Min-Sook;Kim, Kyung-Hee;Kim, Hyeon-A
    • Food Science and Biotechnology
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    • v.18 no.3
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    • pp.712-716
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    • 2009
  • The purpose of this study was to investigate the effect of dietary supplementation of sea tangle (Laminaria japonica) on the blood glucose and lipid metabolism in streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats were divided into 3 groups fed control, sea tangle powder (15%, w/w), or sea tangle water extract (4%, w/w) diet. Diabetes was induced by a single injection of STZ (60 mg/kg, i.p.) in citrate buffer. The animals were fed each of the experimental diet for 13 weeks. Serum insulin was increased by dietary supplementation of sea tangle in diabetic rats. Dietary sea tangle reduced blood glucose level of diabetic rats compared to the diabetic rats fed control diet. Dietary sea tangle also reduced the serum total cholesterol, low density lipoprotein (LDL)-cholesterol, and triglyceride in the diabetic rats. While hepatic lipids were reduced, fecal excretion of lipids was increased by supplementation with dietary sea tangle in the diabetic rats. These results indicate that dietary sea tangle decreased blood glucose and improved lipid metabolism in STZ-induced diabetic rats and this effect might be exerted by increases in serum insulin and fecal excretion of lipids.

Larval Anisakid Infections in Marine Fish from Three Sea Areas of the Republic of Korea

  • Cho, Shin-Hyeong;Lee, Sang-Eun;Park, Ok-Hee;Na, Byoung-Kuk;Sohn, Woon-Mok
    • Parasites, Hosts and Diseases
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    • v.50 no.4
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    • pp.295-299
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    • 2012
  • The present study was performed to determine the infection status of anisakid larvae in marine fish collected from 3 sea areas of the Republic of Korea. Total 86 marine fish (8 species) collected from the East Sea (Goseong-gun, Gangwon-do), 171 fish (10 species) from the South Sea (Sacheon-si, Gyeongsangnam-do), and 92 fish (7 species) from the Yellow Sea (Incheon Metropolitan City) were examined by both naked eyes and artificial digestion method. Among the total of 349 fish examined, 213 (61.0%) were infected with 8 species of anisakid larvae, i.e., Anisakis simplex, 6 types of Contracaecum spp., and Raphidascaris sp., and the mean larval density was 13.8 per infected fish. Anisakid larvae were detected in 45 fish (52.3%) from the East Sea, 131 fish (76.6%) from the South Sea, and 37 fish (40.2%) from the Yellow Sea. The average numbers of larvae detected were 4.0, 16.6, and 15.9, respectively. Anisakis simplex larvae were detected in 149 fish (42.7%), and the mean larval density was 9.0 per infected fish. They were found in 26 fish (30.2%) collected from the East Sea, 96 fish (56.1%) from the South Sea, and 27 fish (29.3%) from the Yellow Sea. The average numbers of larvae detected were 2.9, 10.3, and 10.5, respectively. Conclusively, the present study suggests that the infection rate and density of anisakid larvae are more or less higher in the fish from the South Sea than those from the East Sea or the Yellow Sea.

Variation of Cardiac Output and Blood Pleasure after Flooding Water into Lungs (폐 침수시의 심장 박출량과 혈압의 변동)

  • Cho, Sung-Doo;Nam, Kee-Yong
    • The Korean Journal of Physiology
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    • v.1 no.1
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    • pp.57-66
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    • 1967
  • Cold $(0^{\circ}C)$ or warm $(25^{\circ}C)$ fresh and sea water were flooded into the lungs of rabbits through tracheal canule. Respiratory arrest ensued in 19.5 minutes in the warm fresh water flooded rabbits and was the longest survival time among the experimental groups. The survival times in the other groups were: 2.32 minutes in cold fresh water group, 2.75 minutes in .warm sea water group, and 4.57 minutes in cold sea water group. Cardiac output was measured by means of T-1824 dilution technique after 2 or 3 minutes of flooding in 27 rabbits. Blood pressure was observed by mercury manometer throughout the survival time in 40 rabbits. The following results were obtained. 1. Cardiac output in the warm fresh water flooded and sea water flooded animal was smaller than that of control rabbits. In the cold fresh water flooded animal cardiac output was greater than that of the control animal. 2. Time constants of T-1824 dilution curve of experimental group were elongated than the normal curve. 3. Central blood volume showed an increase in the fresh water group, a decrease in cold sea water group and no change in warm sea water group. 4. In all of the experimental groups arterial blood Pressure showed an abrupt and great variations after flooding of lungs and lasted about 30 seconds. Thereafter, arterial pressure remained at a plateau level until the sudden fall to zero and this was almost coincided with the time of respiratory arrest. The Plateau level of arterial Pressure in fresh water group was about 10 mmHg higher than the control value, and it was lower than the control value in warm sea water group. In cold sea water group the plateau was made up by fluctuations around the control value. 5. Osmosis of water through the lung alveolar membrane occured in all animals. Fresh water caused hemodilution and sea water caused hemoconcentration. 6. In sea water flooded animal more volume of water was recovered through the tracheal canule than the volume injected into trachea. This was interpreted as the consequence of the shift of water from plasma to alveolar sac. 7. Relative freight of lung was greater in fresh water group than sea water group. In all animal lung edema ensued. 8. The mechanisms of cardiac output variations were discussed.

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Occurrence of scutica-like ciliate (SLC) and its control during the mass seed production of the Japanese scallop, Patinopecten yessoensis (참가리비 (Patinopecten yessoensis) 대량 종묘생산시의 Scutica-like ciliate 발생 및 대책)

  • Jo, Q-Tae;Bang, Jong-Deuk;Kim, Su-Kyeong;Rahman, Mohamad M.;Gong, Yong-Geun;Kim, Dae-Kwon;Lee, Joo-Seok
    • Journal of fish pathology
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    • v.21 no.3
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    • pp.167-174
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    • 2008
  • Few studies on parasitic scutica-like ciliates (SLCs) influencing larval growth and survival during the seed production of the Japanese scallop, Patinopecten yessoensis have been performed in spite of relatively high magnitude of their infectious damage to the larvae. In the mass seed production of the scallop, SLCs were never infectious during D-larval stage which lasted 6 to 7 days. Indeed, the infection first occurred in 2 to 4 days after first umbo-staged larvae. A regular selection of active larvae in swimming behavior kept larval SLC infection low throughout the culture compared to unselected control (P<0.05) in which all the larvae alive were contained. Higher infection frequencies of the unselected control resulted in lower larval survivals and wider range of larval size distribution that drove larval attachment rate lower. To the worse, the nursery spats from the higher SLC infection exhibited a retarded growth and elevated occurrence of abnormal scallop.

A Study on the Energy Saving Method by controlling Capacity of Sea Water Pump in Central Cooling System for Vessel (선박용 중앙냉각시스템의 해수 펌프 용량조절에 따른 에너지 절감 기법에 관한 연구)

  • Lee, Ji-Young;Yoo, Heui-Han;Kim, Yun-Hyung;Oh, Jin-Seok
    • Journal of Advanced Marine Engineering and Technology
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    • v.31 no.5
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    • pp.592-598
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    • 2007
  • The fuel charge is getting higher in navigation cost. Therefore, shipowners try to find the method for reducing oil consumption. ESS(Energy Saving System) is one of he method. ESS is the system consisted with two inverters, ESS control unit and monitoring system. Two inverters control two main sea water cooling pumps. In the ESS control Unit, the control algorithm finds optimized point to decrease a power consumption of main sea water cooling pumps. Monitoring system observes ESS not to work improperly. ESS is experimented in the laboratory with real condition and analyzed in every view. After experiment, the result of the experiment shows that the control algorithm works correctly and safely. ESS has a plan to be operated in the ship soon. In that case, additional devices are needed to connect ESS with cooling system of the vessel. So the development of addition device is needed and being studied.

A Sliding Mode Control of Robot Manipulator Operated Under the Sea (해저작업 로봇 매니퓰레이터의 슬라이딩 모드 제어)

  • Park, H.S.;Park, H.I.
    • Journal of the Korean Society for Precision Engineering
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    • v.13 no.12
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    • pp.106-113
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    • 1996
  • This paper presents a modeling of undersea robot manipulators and a control scheme appropriate for manipulating the manipulators working under the unstrcuctured sea water environment. Under the sea, the added mass and added moment of inertia, buoyancy, and drag forces should be considered in modeling the dynamics of the robot manipulators. Due to the complexity of them, the desired dynamics of manipulators can not be accomplished by the conventional control schemes. Hence, a sliding mode control is applied to control the modeling error.

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