• Title/Summary/Keyword: Sea Water Condition

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Wave Simulation for the Optimum Design of Jangjeon Harbour (장전항 최적 설계를 위한 정온도 해석)

  • Hong Keyyong;Yang Chankyu
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.3 no.2
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    • pp.49-59
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    • 2000
  • Wave distribution in Jangjeon Harbour is numerically simulated for an optimum design of the harbour facilities. A deep-water design wave is estimated based on stochastic extreme wave analysis of wind data in the vicinity of the harbour, and it is applied to the boundary condition at open sea. Boussinesq wave theory that includes effects of frequency dispersion and nonlinearity is employed for the wave simulation. The porosity and sponge layer are adapted at beach to depict partial reflection and complete absorption of waves, respectively. The design wave for breakwater is computed in global domain with coarse grids and the wave distribution inside of wharf is simulated in local domain with fine grids.

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A Study on the Fingerprint Recognition Algorithm Using Enhancement Method of Fingerprint Ridge Structure (지문 융선 구조의 향상기법을 사용한 지문인식 알고리즘에 관한 연구)

  • 정용훈;노정석;이상범
    • Journal of the Korea Computer Industry Society
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    • v.4 no.4
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    • pp.647-660
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    • 2003
  • The present of state is situation that is realized by necessity of maintenance of public security about great many information is real condition been increasing continually in knowledge info-age been situating in wide field of national defense, public peace, banking, politics, education etc. Also, loss or forgetfulness, and peculation by ID for individual information and number increase of password in Internet called that is sea of information is resulting various social problem. By alternative about these problem, including Biometrics, several authentication systems through sign(Signature), Smart Card, Watermarking technology are developed. Therefore, This paper shows that extract factor that efficiency can get into peculiar feature in physical features for good fingerprint recognition algorithm implementation with old study finding that take advantage of special quality of these fingerprint.

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Development of fillet-type seasoner and mixed powder-type seasoner using smoked mackerel (훈제 고등어를 이용한 필렛형 조미료 및 복합 분말조미료의 개발)

  • 오영주;오혁수
    • Culinary science and hospitality research
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    • v.7 no.3
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    • pp.145-161
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    • 2001
  • In odor to develop fillet-type seasoner and mixed powder-type seasoner using smoked mackerel as primary material, processing conditions of the mackerel meat and flavoring extract from various materials were examined. The approximate composition of mackerel meat and mixed powde-type seasoner using mackerel as primary material were 10.9 and 11.7%, for moisture 79.1 and 57.2% for crude protein, 5.3 and 2.9% for crude lipid, and 4.3 and 24.6% for crude ash, respectively. It was suitable to simmer raw mackerel in 3% chitooligosaccaride solution at 8$0^{\circ}C$ for 10 min., for the enhancement of reaction their meat and chitooligosaccharide. Considering effect of type of woodsmoke on organoletic properties of mackerel after smoking, oak and mixture(oak wood + citrus wood = 1 : 1) were superior to another woodsmoke, the smoking conditions favoring the most overall preference were 8$0^{\circ}C$, 25min. for smoking time, 20$0^{\circ}C$, 20min. for baking, and 10$0^{\circ}C$. 4hrs. for drying. The optimal material mixing ratio for mixed powder-type seasoner was powder of smoked mackerel 60%, dried anchovy 15%, dried sea tangle 10%. The most appropriate extraction condition of mixed powder seasoner with packing tea bag(10g/bag) was 98$^{\circ}C$ for 5min. in the boiling water.

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A Study on the Actual Condition of Microplastic Contamination in Mackerel

  • Kwon, Woo-Taeg;Kim, Kui-Sung;Lee, Woo-Sik;Kwon, Lee-Seung;Rha, Young-Ah
    • Culinary science and hospitality research
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    • v.24 no.2
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    • pp.119-127
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    • 2018
  • The purpose of this study is to investigate the contamination level of micro plastics in Korean mackerel and to investigate the detection method of micro plastics in fish. This study analyzed the detection and composition of micro plastics using natural mackerel and wild mackerel. 30% hydrogen peroxide and surfactant were added to GF/C filter paper in order to detect micro plastics in the sea. If micro plastics are exposed to the ocean for a long time, accumulation of heavy metals in the water will make pollutant bioaccumulation more serious. Microscopic consequences The risk to human health of plastics has already been studied by many researchers and the risks to human health already caused by marine microorganisms and zooplankton are becoming clear. The conclusion of this study is that there is a difference between the length and height of the mackerel when it is cooked from the standpoint of food in terms of practical implications. The conclusion of this study is that the probability of micro-plastic-contaminated mackerel to reach and be consumed by end-consumers is low in academic implications. Residual contaminants adsorbed on micro plastics are absorbed by digestive organs and cause disruption, and further research on micro plastics is needed in the future.

Biodegradation of Diesel by Rhodococcus fascians in Sand Column (Rhodococcus fascians를 이용한 모래 컬럼내 디젤유 분해)

  • Moon, Jun-Hyung;Koo, Ja-Ryong;Yun, Hyun-Shik
    • KSBB Journal
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    • v.26 no.1
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    • pp.1-6
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    • 2011
  • Contamination of soils, groundwater, air and marine environment with hazardous and toxic chemicals is major side effect by the industrialization. Bioremediation, the application of microorganism or microbial processes to degrade environmental contaminant, is one of the new environmental technologies. Because of low water solubility and volatility of diesel, bioremediation is more efficient than physical and chemical methods. The purpose of this study is biodegradation of diesel in sand by using Rhodococcus fascians, a microorganism isolated from petroleum contaminated soil. This study was performed in the column containing sand obtained from sea sides. Changes in biodegradability of diesel with various flow rates, inoculum sizes, diesel concentrations, and pH were investigated in sand column. The optimal condition for biodegradation of diesel by R. fascians in sand column system was initial pH 8 and air flow rate of 30 mL/min. Higher diesel degradation was achieved at larger inoculum size and the diesel degradation by R. fascians was not inhibited by diesel concentration up to 5%.

A Study on Modelling for Prediction of Concrete Drying Shrinkage according to Properties of Aggregate (잔골재 특성에 따른 콘크리트 건조수축 모델링에 관한 연구)

  • Park Do-Kyong;Yang Keek-Young
    • Journal of the Korea Institute of Building Construction
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    • v.6 no.1 s.19
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    • pp.73-77
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    • 2006
  • Drying Shrinkage has much complexity as it has relations with both internal elements of concrete and external factors. Therefore, experiments on Concrete Drying Shrinkage are carried out in this study under simplified circumstances applying temperature & Humidity test chamber which enables constant temperature and humidify. Comparative analyses have been made respectively according to the consequences aiming at modelling for prediction of Concrete Drying Shrinkage and making out measures to reduce it. As a result Strain Rate of Drying Shrinkage of concrete was measured to increase by average $10{\times}10^{-5}$ in proportion to additional 4% increase in fine aggregate ratio, when water/cement ratio constant. Strain Rate of Drying Shrinkage in pit sand concrete increased 20% higher than measured when in river sand under the condition of 90-day material age. 6. Strain Rate of Drying Shrinkage in sea sand concrete increased $10%{\sim}15%$ higher than measured when in river sand. The results of prediction of Rate of Drying Shrinkage by Response Surface Analysis are as fellows. The coefficient of correlation of Drying Shrinkage in concrete was over 90%.

Fundamental Study on Cathodic Protection and Material Development as Erosion-Control Methods of Oceanic Centrifugal Pump(1) (해상용 원심펌프 임펠러의 침식억제법으로 음극방식 및 재료개발에 관한 기초연구 1)

  • 이진열;임우조
    • Journal of Advanced Marine Engineering and Technology
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    • v.19 no.2
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    • pp.56-66
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    • 1995
  • Recently, with theraped advancement in th oceanology such an ocean-going vessel and oceanic structures, there is a need to study the cavitation erosion-corrosion control of pump impeller, the partial element of ocean machinery, for more effective operation. Especially, the cathodic protection (impressed current method & Al-sacrificial anode method) was applied to sea water, and Cu-alloy material mixed Zn & Al was used as a control method of cavitation erosion-corrosion. In this study, used the piezoelectric vibrator with 20KHz, 24.mu.m to cavity generation apparatus, and investigated the weight loss, weight loss rate, electrode potential & current density etc. under this condition. According to test result, thos describes how to indentify an influence of the cathodic protection and Al & Zn addition in material development for the control of cavitation erosion-corrosion, and those will serve as fundamental data on the cavitation erosion-corrosion control of oceanic centrifugal pump.

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Contribution Analysis to Identify the Source of Ship Hull Vibration (선체 진동 특성 규명을 위한 기여도 분석)

  • Lee, Jun Woo;Ahn, Se Jin;Oh, Jun Seok;Kim, Tae Hyeong;Jeong, Weui Bong
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.26 no.5
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    • pp.528-535
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    • 2016
  • The vibration of a ship gives a significant effect on the noise radiated into the water. This paper focused on the vibration of ship hull due to the sub-generator located on the deck in the anchored condition. The contributions of the transfer paths between sub-generator and ship hull were analyzed using the TPA and the OTPA method. While the sub-generator was operation and the main engine was turned off, the vibrations were measured simultaneously at the 38 locations of the ship and the one hydrophone was arranged to measure the underwater radiated noise at the overside ship. The results of the transfer path by applying TPA and OTPA were compared and discussed. As a result of these methods, the top of stovepipe and valve are contributive. Reinforcing these structures is the most effective to reduce the vibration of ship hull.

Corrosion behaviors of cement mortar specimens with different cover thickness in natural sea water

  • Jeong, Jin-A;Jin, Chung-Kuk;Jeong, Eun-Seok
    • Journal of Advanced Marine Engineering and Technology
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    • v.40 no.2
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    • pp.107-111
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    • 2016
  • This paper presents electrochemical corrosion behaviors of cement mortar specimens in the high salinity condition. Chloride ion is known as the most detrimental parameter to cause the corrosion in reinforced concrete. Increasing the concrete cover thickness is one of the corrosion protection methods against chloride ion; so, this study mainly focuses on the effects of mortar cover thickness on corrosion protection. In specimens, rebar, which was a height of 200 mm and a diameter of 10 mm, was installed at the center of the small size form. Later on, mortar was injected into the form, and 10, 20, 30, 40, and 50 mm of the different mortar cover thicknesses were selected. Potential measurements, linear polarization resistance tests, and cyclic potentiodynamic polarization tests were performed for specimens that were exposed to seawater. These results were compared with visual inspection results of rebar. The results show that an increase in the cover thickness contributes to corrosion protection. In addition, the result of electrochemical corrosion tests generally agreed with that of an autopsy visual inspection.

Spatial Variations of Heavy Metal Accumulation in Manila clam Ruditapes philippinarum from Some Selected Intertidal Flats of Korea (우리나라 갯벌 조간대 바지락 Ruditapes philippinarum의 지역별 중금속 농축 변화)

  • Ahn In-Young;Ji, Jung-Youn;Choi, Hee-Seon;Pyo, Sei-Hong;Park, Hyun;Choi, Jin-Woo
    • Ocean and Polar Research
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    • v.28 no.3
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    • pp.215-224
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    • 2006
  • Spatial variation of heavy metal accumulation was investigated in Manila clam Ruditapes philippinarum collected from several tidal flats. Sediment metal levels varied highly among the sites, which was attributed primarily to differences in Fe and organic carbon contents and in part to gain size. Significant differences in metal concentrations also were found in the clam tissue among the different sampling sites. However, except for a few metals (Mn, Zn, Pb), which showed some elevation, the variations in the clam tissue were not related to the variations in the sediment. This is likely because most metals in filter-feeding herbivores such as R. philippinarum accumulated as a result of feeding on suspended particles such as phytoplankton and organic detritus in the water column, not in bottom sediment. In addition, tissue weight for a specific shell size varied significantly among the sites, and increased tissue mass indicating a good nutritive condition likely caused a subsequent dilution of body metals leading to reduced weight-specific concentrations of some metals (Cd, Zn, Cu, Co).