• Title/Summary/Keyword: non-marine

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Design charts for estimating the consolidation times of reclaimed marine clays in Korea

  • Sang-Hyun Jun;Byung-Soo Park;Hyuk-Jae Kwon;Jong-Ho Lee
    • Geomechanics and Engineering
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    • v.32 no.1
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    • pp.1-20
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    • 2023
  • To predict the consolidation behavior of dredged and reclaimed marine clays exhibiting consolidation settlement with large strains, the finite strain consolidation theory must be used. However, challenges in appropriately applying the theory and determining input parameters make design and analysis studies difficult. To address these challenges, design charts for predicting the consolidation settlement of reclaimed marine clays are developed by a numerical approach based on the finite strain consolidation theory. To prepare the design charts, a sensitivity analysis of parameters is performed, and influencing parameters, such as initial void ratio and initial height, as well as the non-linear constitutive void ratio-effective stresspermeability relation, are confirmed. Six representative Korean marine clays obtained from different locations with different liquid limits are used. The design charts for estimating the consolidation times corresponding to various degrees of consolidation are proposed for each of the six representative clays. The consolidation settlements predicted from the design charts are compared to those in previous studies and at an actual construction site and are found to agree well with them. The proposed design charts can therefore be used to solve problems related to the consolidation of reclaimed marine clays having large strains.

An experimental study on heat transfer characteristics of variable conductance heat pipe (가변전열 히이트 파이프의 특성에 관한 연구)

  • 김주년;이영호;김용모
    • Journal of Advanced Marine Engineering and Technology
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    • v.8 no.1
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    • pp.4-16
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    • 1984
  • The heat-pipe is characterised by the highly effective thermal conductance. In order to change the thermal conductance, the heat-pipe is connected to a reservior having a space which is filled with non-condensable gas. In normal operation, the vapour of working fluid will tend to pump the non- condensable gas into the reservoir and the gas-vapour interface situates at some point along the condenser section. The thermal conductance is affected by non- condensable gas. It is concluded that the suitable position of interface can be used to control the temperature of condenser section. In this experiment, the evaporating part is connected to the lowest position of heat-pipe. The copper heat-pipe which is filled with Freon-113 or distilled water as working fluid utilized. As results of experimental study, thermal conductance can be increased by the operating pressure which is infulenced by non-condensable gas. A correlative equation between the thermal conductance and the mass of non- condensable gas is also obtained.

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A Study on the Stress Analysis ofAxi-symetric Body with N on-symetric Load and N on-symetric Given Displacements (비대칭 하중을 받고 비대칭 변위가 주어진 축대칭 물체의 응력해석에 관한 연구)

  • 전효중;왕지석;최순열
    • Journal of Advanced Marine Engineering and Technology
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    • v.14 no.4
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    • pp.46-56
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    • 1990
  • Stress analysis of axi-symetric body with non-symetric loading and non-symetric given displacements is investigated in this paper using the finite element method. As the non-symetric load and non-symetric given displacements of axi-symetric body are generally periodic functions of angle .theta., the nodal forces and nodal displacements can be expanded in cosine and sine series, that is, Fourier series. Furthermore, using Euler's formula, the cosine and sine series can be converted into exponential series and it is prooved that the related calculus become more clear. Substituting the nodal displacements expanded in Fourier series into the strain components of cylindrical coordinates system, the element strains are expressed in series form and by the principal of virtual work, the element stiffness martix and element load vector are obtained for each order. It is also showed that if the non-symetric loads are even or odd functions of angle ${\theta}$ the stiffness matrix and load vector of the system are composed with only real numbers and relatively small capacity fo computer memory is enough for calculation.

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Study on the Characteristics and Non-point Source Pollution Loads in Stormwater Runoff of Shihwa Lake (시화호 유역 비점오염물질의 유출특성 및 부하량 연구)

  • Ra, Kong-Tae;Kim, Kyung-Tae;Kim, Joung-Keun;Bang, Jae-Hyun;Lee, Jung-Moo;Kim, Sung-Keun;Kim, Eun-Soo;Yun, Min-Sang;Cho, Sung-Rok
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.14 no.1
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    • pp.40-50
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    • 2011
  • We study the characteristic and total flux of non-point pollutants such as total suspended solids (TSS), chemical oxygen demand (COD), dissolved nutrients, total phosphorus (TP) and total nitrogen (TN) in the storm water runoff from urban streams and sewer outlets of Banweol Industrial Complex around Shihwa Lake. The concentrations of non-point pollutants were generally increased with increasing of the duration and intensity of rainfall. Mean TSS concentration of Ansan stream was higher than that of sewer outlets but mean concentrations of COD, TP and TN were approximately 2~5 times higher of sewer outlet than of urban stream. TSS showed statistically positive relationships with COD and TP but it had negative correlation with dissolved nutrients. There was a significant correlation between total flux of non-point pollutants in the storm water runoff and total basin area of each sewer outlet, showing that the highest runoff flux was observed at 3rd sewer outlet which represents the largest basin area from Banweol industrial complex. Total runoff fluxes for TSS, COD, TP and TN in this study were 187,536 kg, 17,118 kg, 922 kg, 13,519 kg, respectively. Given the basin area of sewer outlet in Banweol industrial complex which corresponds only 3% from total catchment area around Shihwa Lake, enormous amount of non-point pollutants will be entered into Shihwa Lake without any treatment. It is necessary to manage and reduce of various non-point sources and pollutants because the runoff of nonpoint pollutants during storm events should be deteriorating the water quality of Shihwa Lake. Our results provides useful informations on the development of best managements practices (BMPs) for effective implementation of total pollution loads management system of Shihwa Lake.

Elementary School Teachers' Perceptions of Marine Aquaria Field Trips and Educational Roles of Marine Aquaria (초등교사의 해양수족관 현장학습에 대한 인식과 해양수족관의 교육적 기능)

  • Kim, Jong-Mun
    • Journal of Fisheries and Marine Sciences Education
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    • v.24 no.3
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    • pp.459-467
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    • 2012
  • Marine aquariums are excellent venues for accomplishing the purpose of marine education, and school field trips conducted at non-formal settings continue to be an important part of K-12 education. The purpose of this study is to provide quantitative data regarding the extent and quality of marine aquarium field trips conducted by elementary school teachers in Seoul. A web survey designed to explore elementary school teachers' experiences and perspectives on aquarium field trips identified several concerns regarding Korean marine aquarium education. Discussions for both Korean aquaria's educational roles and Korean elementary schools' successful field trips to aquaria are presented with the goal of improving the quality of Korean marine aquarium education.

Change of Various Characteristics between Spawning and Non-spawning Season in Diploid and Induced Triploid Far Eastern Catfish, Silurus asotus

  • Lim, Sun Young;Gil, Hyun Woo;Park, In-Seok
    • Development and Reproduction
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    • v.21 no.3
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    • pp.275-286
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    • 2017
  • The purpose of this study is to investigate the differences fatty acids and hormonal parameters in the spawning and non-spawning season between the diploid and induced triploid Far Eastern catfish, Silurus asotus. The measured triploids were produced by cold shock for 50 min at $4^{\circ}C$ in May 2014, the spawning season of diploid was in May, and the non-spawning season was designated in January. Estradiol and testosterone and gonadosomatic index of diploid were higher than those of induced triploid in spawning season (P<0.05), and those of diploid in spawning season were higher than non-spawning season. On the other hand, thyroid stimulating hormone and thyroxine of induced triploid were higher than those of diploid in spawning season (P<0.05). Erythrocyte count of diploid was higher than that of induced triploid in spawning season and non-spawning seasons. Mean corpuscular volume and mean corpuscular hemoglobin of induced triploid were higher than those of diploid in both seasons (P<0.05). Percentages of total saturated fatty acids and n-3 polyunsaturated fatty acids of induced triploid were higher than those of diploid in spawning season, but those of diploid were higher in non-spawning season (P<0.05). Percentages of total mono unsaturated fatty acids and total n-6 polyunsaturated fatty acids of diploid were higher than those of induced triploids in spawning season, while those of induced triploid in non-spawning season were higher (P<0.05). Therefore, induced triploids in the spawning season tend to concentrate on growth and lipid-synthesization, whereas, diploids concentrate on reproduction and gonadal maturation rather than on growth. In non-spawning season, growth and lipid-synthesization were not significantly different between diploid and induced triploid.

Effect of Dietary Supplementation with Alga (Hizikia fusiformis and Ecklonia cava) on the Non-specific Immune Responses of Parrot Fish Oplegnathus fasciatus (사료 내 해조류(톳, 감태) 첨가가 돌돔(Oplegnathus fasciatus) 치어의 비특이적 면역반응에 미치는 영향)

  • Song, Jin-Woo;Jang, Ji-Woong;Kim, Sung-Sam;Oh, Dae-Han;Cha, Ji-Hoon;Lee, Kyeong-Jun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.4
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    • pp.332-338
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    • 2011
  • Two feeding trials were conducted to determine the effects of dietary supplementation with Hizikia fusiformis or Ecklonia cava on the non-specific immune responses of parrot fish Oplegnathus fasciatus. Fish were fed experimental diets to which H. fusiformis or E. cava powder were added to final concentrations of 0, 2, 4 and 6%, respectively. After feeding for two weeks, phagocytic activity was significantly higher in fish fed diets containing H. fusiformis, but not E. cava, than in fish fed the basal diet. Lysozyme activity was significantly increased in the fish fed diets containing 6% H. fusiformis and E. cava. Myeloperoxidase activity was also significantly higher in fish fed diets containing 2 and 4% H. fusiformis, as compared to the basal diet, but not in those fish fed E. cava. These two studies indicate that dietary supplementation with H. fusiformis or E. cava could enhance the innate immune responses of parrot fish during their growth stage.

Insurance-Growth Nexus: Aggregation and Disaggregation

  • ZULFIQAR, Umera;MOHY-UL-DIN, Sajid;ABU-RUMMAN, Ayman;AL-SHRAAH, Ata E.M.;AHMED, Israr
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.12
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    • pp.665-675
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    • 2020
  • The aim of this article is to investigate the relationship between insurance and economic growth at aggregate and disaggregate level for the period 1982-2018. Very few studies have been carried out in this field, with contradictory results and using an aggregate data while, according to different authors, an aggregate data might provide spurious results. The author used Ordinary Least Squares Regressions (OLS) and Granger Causality tests to explore the strength and direction of the relationship between insurance and economic growth at an aggregate level. To check the relationship at disaggregate level life insurance, marine insurance, and property insurance are regressed on trade openness and investment, respectively. Non-life insurance at an aggregate level plays a positive and significant role in promoting economic growth, but life insurance has an insignificant impact on the Pakistan economy. On the other hand, non-life insurances at a disaggregated level such as marine insurance negatively affect a vital part of economic growth, i.e., trade. At the same time, property insurance has a significant and positive role in boosting investment. Life, marine, and property insurance Granger cause economic growth, trade, and investment in a single direction. Nevertheless, is a bi-directional relationship between economic growth and non-life insurance.

Characteristics of Settling and Consolidation Behavior for Non-Plastic Dredged Soils (비소성 준설토의 침강-압밀 거동 특성)

  • Park, Yun-Gyun;Park, Byung-Soo;Jeong, Gil-Soo;Yoo, Nam-Jea
    • Journal of Industrial Technology
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    • v.24 no.A
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    • pp.251-261
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    • 2004
  • A series of column test with a silty marine soil mixed with Jumunjin Standard Sand were performed to investigate the characteristics of settling and consolidation of non-plastic dredged soils. Column tests were carried out by using the separable column to measure the grain size distribution of consolidated layer. Column tests were performed with changing the mixing ratio of Jumunjin Standard Sand to the silty marine soil, initial water content of slurry and initial height of slurry. Height of interface of slurry was monitored during tests and grain size distribution tests were carried out after finishing tests. Influencing factors on the particle segregation, eventually to the characteristics of settling and consolidation of non-plastic soil, were analyzed on the thesis of test results. As results of column tests, the mixing ratio of sand to the silty marine soil and the initial water content of slurry were known to affect the characteristics of settling and consolidation resulted in significant particle segregation of slurry. Initial height of slurry was found not to affect seriously to particle segregation.

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Effect of Korean Mistletoe (Viscum album Coloratum) on the Non-Specific Immune Responses in Japanese Eel (Anguilla japonica)

  • Cho, Young-Hye;Choi, Dae-Han;Choi, Sang-Hoon
    • Journal of fish pathology
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    • v.18 no.1
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    • pp.59-66
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    • 2005
  • In the present paper, the immunostimulatory effects of Korean mistletoe (Viscum album Coloratum) on the non-specific immune responses of Japanese eel (Anguilla japonica) were examined. Eel were innoculated with mistletoe, Freund's complete adjuvant (FCA), or phosphate-buffered saline (PBS) as a control into their peritoneal cavities. The number of nitrobule tetrazolium (NBT)-positive cells in the head kidney of fish was significantly increased by the second day post-injection of mistletoe. ROI products were more enhanced in mistletoe-injected fish kidney leucocytes than in FCA-injected ones. The level of lysozyme activity detected in the serum of fish 2 days after injection with mistletoe was also significantly higher than that found in the serum of the control fish. The appropriate concentration of mistletoe to induce the highest level of serum lysozyme activity was revealed to 1000${\mu}g$/200 g of fish. In phagocytic activity assay, mistletoe-sensitized eel kidney phagocytes captured more zymosan than did the control fish. Korean mistletoe appeared to be a good activator of the non-specific immune responses of Japanese eel.