• Title/Summary/Keyword: Sea Control

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Heading Control of URI-T, an Underwater Cable Burying ROV: Theory and Sea Trial Verification (URI-T, 해저 케이블 매설용 ROV의 선수각 제어 및 실해역 검증)

  • Cho, Gun Rae;Kang, Hyungjoo;Lee, Mun-Jik;Li, Ji-Hong
    • Journal of Ocean Engineering and Technology
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    • v.33 no.2
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    • pp.178-188
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    • 2019
  • When burying underwater cables using robots, heading control is one of the key functions for the robots to improve task efficiency. This paper addresses the heading control issue for URI-T, an ROV for underwater construction tasks, including the burial and maintenance of cables or small diameter pipelines. Through modeling and identifying the heading motion of URI-T, the dynamic characteristics and input limitation are analyzed. Based on the identification results, a PD type controller with appropriate input treatment is designed for the heading control of URI-T. The performance of the heading controller was verified in water tank experiments. The field applicability of the proposed controller was also evaluated through the sea trial of URI-T at the East Sea, with a water depth of 500 m.

Biochemical analysis of blood serum from wintering seabream with green liver syndrome (저수온기 돔류의 녹간증 혈청성분)

  • Choi, Hye-Sung;Park, Sung-Real;Jung, Choon-Goo
    • Journal of fish pathology
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    • v.15 no.1
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    • pp.43-48
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    • 2002
  • A blood biochemical analysis was carried out for the serum of wintering sea bream (red sea bream Pagrus major, black sea bream Acanthopagrus schlegeli, rock bream Oplegenathus fasciantuas) with green liver syndrome. GOT and GPT were significantaly elavated in the diseased sea bream. The value of $NH_{3}$ was slightly higher but those of TBIL. TP and UA were lower than the control. But there were no differences in albumin. Ca and glucose between the diseased and the control. These results suggent that a green liver syndrome in the sea bream might be related with nutritional defects and the stress of low water temperature during the winter.

Antitumor Effects of Glycoportein Extracted from Sea Cucumber (Stichopus japonicus)

  • Moon, Jeung-Hye;Ryu, Hong-Sool;Suh, Jae-Soo
    • Preventive Nutrition and Food Science
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    • v.4 no.2
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    • pp.117-121
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    • 1999
  • The anititumor and immunologic activities of the glycoproteins extracted from sea cucumber (Stichopus japonicus) on mice bearing sarcoma 180 cells were investigated . Maximum tumor suppression (64%) occurred at the dose of 100mg glycoprotein/kg. The highest prolongation ratio was achieved at the level of 100mg/kg an dincreased by 395 more than that of control. Glycoproteins from sea cucumber exhibited direct cytotoxic effect on the tumor cells. Dose dependent increase of leucocyte, peritoneal exudate cell and weights of immunoorgans revealed the improvement of immunity. When the glycoportein-administered group was compared with the control, a significant difference was not noted in the clinico-chemical values such as S-GOT, S-GPT , alkaline phoshatse activity, total protein, cholesterol, triglyceride, urea nitrogen and glucose levels in blood. These results suggests that the antitumor activity of sea cucumber glycoprotein is associated with activation of cells in the immune system.

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Hypoglycemic and Antioxidative Effects of Dietary Sea-Tangle Extracts Supplementation in Streptozotocin-Induced Diabetic Rats (Streptozotocin-유발 당뇨쥐에서 다시마 추출물 첨가식이의 항당뇨 및 항산화 효과)

  • 조영자;방미애
    • Journal of Nutrition and Health
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    • v.37 no.1
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    • pp.5-14
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    • 2004
  • The purpose of this study was to investigate the effect of dietary sea-tangle extracts on blood glucose levels, serum lipid levels, thiobarbituric acid reactive substance (TBARS) and glutathione enzymes in diabetic rats treated with streptozotocin (STZ) Four groups of rats (Sprague-Dawley male rats, 180 - 200g) were consisted of normal rats fed control diet (C), diabetic rats fed control diet (CD), normal rats fed sea-tangl extracts diet (E), and diabetic rats fed sea-tangle extracts diet (ED). Diabetes was induced by single injection of streptozotocin (60 mg/kg B.W.). After 7 weeks, rats were sacrificed, serum glucose, serum total cholesterol, triglyceride levels and glutathione enzymes were measured. Urine was significantly higher in CD and ED groups than those of others (p < 0.05). Levels of amylase, calcium, uric acid, hemoglobin, cholesterol and low density lipoprotein (LDL)-cholesterol were different among four groups. But high density cholesterol (HDL)-cholesterol of ED group was significantly higher (p < 0.05) than other groups (C and E group) And the weekly change of serum glucose was decreased in the 3th,4th and 5th weeks. But serum triglyceride (TG) of diabetic rats fed sea-tangle extracts diet (ED) was lower than diabetic rats fed control diet (CD). Activity of hepatic microsomal G6Pase was significantly increased CD and ED groups higher than C and E group, but kidney was decreased ED group. Hepateic glutathione S-transferase (GST) of CD and ED group were significantly lower than C and E group (p<0.05), glutathione peroxidase (GPX) of E and ED group were significantly higher than C and CD group (p<0.05), glutathione reductase (GR) activities of ED group was significantly lower than other groups, malondialdehyde (MDA) of ED was lower than E and CD group, but kidney was increased significant in ED group compared to liver. These results suggested that dietary sea-tangle extracts reduce .hepatic disorders such as oxidant than kidney. In conclusion, dietary sea-tangle extracts groups reduced blood TG and hepatic MDA levels in STZ-induced diabetic rats.

A Study on the Regional Cooperation for the Prevention of Marine Pollution in the Yellow Sea (황해에 있어서의 해양오염방지를 위한 지역적 협력에 관한 연구)

  • 이윤철;최성규
    • Journal of the Korean Institute of Navigation
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    • v.16 no.2
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    • pp.41-52
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    • 1992
  • It is, as everyone knows, very important for human beings to protect and conserve marine environment. We has believed the ocean is so wide and deep that it cannot be polluted. But it has begun to doubt the capacity of self-purification of the ocean due to pollution arising from marine casualities. It has proved that semi-enclosed sea is likely to be polluted and cannot be restored easily once pollution occurs. Therefore, first of all it is important to take preventive measures for prevention of marine pollution in the semi-enclosed sea like the Yellow Sea. Many of regional conventions for prevention of marine pollution have come into existence. this dissertation was set out for the fact that the Yellow Sea is semi-enclosed sea which is vulnerable to marine pollution. It is desirable not to deal with marine preservation of the Yellow Sea by a single exclusively but to deal with it by cooperation of all coastal states under the present circumstances. I proposed a program of regional cooperation to protect and conserve the Yellow Sea. This program must be progressed with gradual arrangements. First, they must establist a basic cooperation committee to work basic affairs on the protection of marine environment within the Yellow Sea. The Committee Mainly play parts of study and research concerned with pollution of the Yellow Sea in the non-governmental side and consist of legal and scientific experts. Second, they must establish the control Committee to prevent marine pollution of the Yellow Sea substantially. There is a reason that regional cooperation cannot be directly concluded with the regional tready. Because there is a problem of Recognition of States left. In principle, a subject of tready must be a state in the International Law. But they have not made Recognition of State which is demanded by International Law between North and South Koreas. Therefore, the Control committee must play a substantial part of prevention from pollution instead of the treaty. Finally, we concluded tentatively named $\ulcorner$Convention on Regional Cooperation for Protection of Marine Environment of the Yellow Sea from Pollution$\lrcorner$ if the matter is settled which is related to Recognition of States in the International Law.

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Effect of Addition of Mushroom and Sea Tangle Extracts and Mustard Leaf on Anti-oxidant Properties of Kimchi (버섯 및 다시마 추출물과 갓의 첨가가 김치의 항산화 특성에 미치는 영향)

  • Ha, Seon-Hye;Kang, Soon Ah
    • The Korean Journal of Food And Nutrition
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    • v.31 no.4
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    • pp.471-477
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    • 2018
  • The antioxidant properties of mushroom and sea tangle extracts and mustard leaf added to Kimchi were investigated by total phenolic content, DPPH radical scavenging, ABTS anion scavenging, FRAP reducing power, and ORAC value. Total phenolic content of functional Kimchi (FK) was significantly higher than that of control Kimchi (CK). DPPH radical and ABTS anion scavenging activities of functional Kimchi were significantly higher than those of control Kimchi by 2.7 and 1.7 fold, respectively (p<0.05). Also, the FRAP reducing power and ORAC value of functional Kimchi increased compared to those of the control Kimchi by 1.6 and 1.1 fold, respectively (p<0.05). Our results suggest that functional Kimchi made by mushroom and sea tangle extracts and mustard leaf may be a potent antioxidant source and could be developed as a antioxidant functional food that may be for the effective treatment of oxidant conditions. Through continuous research and development of functional Kimchi by the use of mushroom and sea tangle extracts, it will be necessary to try to identify other functions that could be useful for preventing various diseases.

A Robust Neural Control of Robot Manipulator Operated Under the Sea (해저작업 로봇 매니퓰레이터의 강건한 신경망 제어기)

  • 박예구;최형식;이민호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.10a
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    • pp.337-341
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    • 1995
  • This paper presents a robust control scheme using a multilayer network for the robot manipulator operating under the sea which has large uncertainties such as the buoyancy and the added mass/moment of inertia. The multilayer neural network acts as a compensator of the conventional sliding mode controller to maintain the control performance when the initial assumptions of uncertainty bounds are not valid. By the computer simulation results, the proposed control scheme dose not effectively compensate large uncertainties, but also reduces the steady stare error of the conventional sliding mode controller.

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Antioxidative Activity of Sea Buckthorn and Quality Characteristics of Brown Rice Sulgidduk (비타민나무 잎 첨가 현미설기떡 제조 및 항산화 활성)

  • Cho, Gang-Sug;Kim, Ae-Jung
    • Human Ecology Research
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    • v.53 no.1
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    • pp.17-27
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    • 2015
  • This study was performed to investigate the antioxidative properties of sea buckthorn (Hippophae rhamnoides L.; leaf, fruit and stem) and the quality characteristics of brown rice sulgidduk prepared using a powder of sea buckthorn leaves. First, the antioxidative activities of sea buckthorn were measured to choose the most effective part of this plant. By analyzing the measured values, we concluded that the effective part of sea buckthorn was its leaves. The $IC_{50}$ value of the DPPH radical scavenging activity and the ABTS radical scavenging activity in sea buckthorn leaves were $7.78{\mu}g/mL$ and $264.04{\mu}g/mL$, respectively. The total polyphenol and total flavonoid contents of sea buckthorn leaves were 3.80 mg/mL and .19 mg/mL, respectively. Therefore, the brown rice sulgidduk was prepared using a powder of sea buckthorn leaves in the weight ratio of 0%, .5%, 1.0%, 1.5%, 2.0% and 2.5%. For analyzing the quality characteristics of the prepared sulgidduk, proximate compositions, color and texture profiles were measured and a sensory evaluation was conducted. With an increase in the added content of the sea buckthorn leaf powder (SBLP), the L-value significantly decreased while the a-value and the b-value increased. In the case of texture profiles, the control group (control A) had a higher score for hardness than the case groups in which the SBLP was added. However, springiness, chewiness and adhesiveness were not significantly different among the groups. In the sensory evaluation, the sample containing 1.5% SBLP yielded the best results. Therefore, we suggest that the powder of sea buckthorn leaves is a good ingredient for increasing the consumer acceptability and functionality of sulgidduk.

The influence of sea surface temperature for vertical extreme wind shear change and its relation to the atmospheric stability at coastal area

  • Geonhwa Ryu;Young-Gon Kim;Dongjin Kim;Sang-Man Kim;Min Je Kim;Wonbae Jeon;Chae-Joo Moon
    • Wind and Structures
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    • v.36 no.3
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    • pp.201-213
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    • 2023
  • In this study, the effect of sea surface temperature (SST) on the distribution of vertical wind speed in the atmospheric boundary layer of coastal areas was analyzed. In general, coastal areas are known to be more susceptible to various meteorological factors than inland areas due to interannual changes in sea surface temperature. Therefore, the purpose of this study is to analyze the relationship between sea surface temperature (ERA5) and wind resource data based on the meteorological mast of Høvsøre, the test bed area of the onshore wind farm in the coastal area of Denmark. In addition, the possibility of coastal disasters caused by abnormal vertical wind shear due to changes in sea surface temperature was also analyzed. According to the analysis of the correlation between the wind resource data at met mast and the sea surface temperature by ERA5, the wind speed from the sea and the vertical wind shear are stronger than from the inland, and are vulnerable to seasonal sea surface temperature fluctuations. In particular, the abnormal vertical wind shear, in which only the lower wind speed was strengthened and appeared in the form of a nose, mainly appeared in winter when the atmosphere was near-neutral or stable, and all occurred when the wind blows from the sea. This phenomenon usually occurred when there was a sudden change in sea surface temperature within a short period of time.

Development of a Remotely Operated Vehicle for Investigation the Coastal Sea (근해 조사용 무인잠수정의 개발)

  • Kim, Kyeong-Ki;Choi, Hyeung-Sik;Kang, Hyung-Suk;Jeong, Gu-Rak;Gwon, Kyeong-Yeop
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.32 no.11
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    • pp.997-1002
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    • 2008
  • This paper is mainly concerned with the development of a remotely operated vehicle for investigation of the coastal sea. For this, we have designed and constructed a vehicle entitled KMU-ROV(Korea Maritime University Remotely Operated Vehicle), for purpose of investigation mission under 50(m) of the sea surface. We have designed six independent waterproof actuators and the housing of the controller for underwater operation. For six degree-of-freedom motion, we have analyzed the dynamics of the KMU-ROV and have designed a new composition of six actuators including the driving system. For motion control, we have composed a concurrent velocity control algorithm for controlling the speed of all the actuating motors. The control system for the KMU-ROV is composed of a master DSP controller, DSP controller for the motor control and various sensors. We composed the PID control algorithm and a network system for controlling motors using the CAN communication. The performance of the KMU-ROV was presented by testing the developed control algorithm and control system under the water.