• Title/Summary/Keyword: Bunker

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Oilspill Damage Assessment of Natural Fisheries Resources by Ecological Models (생태학적 모델을 이용한 유류유출 사고에 의한 자연 수산자원 피해의 추정)

  • YOO Sin jae;SHIN Kyoung Soon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.2
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    • pp.174-190
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    • 1996
  • Damage assessment based on in situ surveys for oil spills in marine environment is limited by fundamental difficulties as well as tremendous expenses. Except for intertidal zones, the damage is not preserved well. Also such surveys are usually confined to adult organisms. To overcome these limitations a computer model, NRDAM/CME, was developed in the case of USA (Reed et al., 1989), where an acute toxicity data base was used to assess indirect damages through food webs and loss due to recruitment as well as adult losses. In the present study damage assessment of natural biological resources for hypothetical oil spills is attempted using a computer model for hypothetical spills of Bunker C and heavy crude oil. In the model, the logical structure of NRDAM/CME was adopted, and biomass and productivity database were compiled for the Korean waters. The results showed that the damage increased in a nonlinear fashion as the spill amount increased. The magnitude of the damage depended upon the chemical properties of oil viscosity and solubility in particular, which implies that usage of oil dispersant might increase the damage by dispersing oil. The results also indicate that long term damage due to recruitment loss could be greater than short term damage.

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Environment Analysis of Kwangyang Bay after the Keumdong Oil Spill

  • Park, Yong-Chul;Han, Myung-Woo;Kim, Sung-Jun;Chung, Kyung-Ho;Son, Seung-Kyu;Chung, Jin-Won
    • Journal of the korean society of oceanography
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    • v.33 no.4
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    • pp.168-177
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    • 1998
  • Five and a half months after the Keumdong oil spill accident on the 21$^{st}$ of September 1993, 34 seawater samples and 94 sediment samples were collected from Kwangyang Bay and Namhaedo area to assess its environmental impacts. Hydrocarbon concentration in the seawater ranged from 0.8 to 9.2 ${\mu}$g/1 with an average of 3.3 ${\mu}$g/1. This average value was nearly the same as the value(3.7 ${\mu}$g/1) before the oil spill accident. This suggests that by the early March of 1994 majority of the coastal water in the study area restored to its background hydrocarbon concentration before the oil spill accident. Nutrients, heavy metals and other general environmental parameters of the seawater did not show any aggravated seawater quality compared with the previous records. From the regression analysis of time-course observation of hydrocarbon in the seawater, except the sediment environment, the effect of oil spill on the water column was estimated to last at least 4 months in the study area after the oil spill accident. In the shoreline sediments, oil deposits were, however, still found at the high water marks at several stations, and very high values were found in the west of Namhaedo, ranging from 3.7 to 40.1 mg/g of wet sediment. Gas chromatography of these samples showed a very distinct Bunker C chromatogram identical to the Keumdong oil spill. Hydrocarbons in the subtidal bottom sediments in the study area and the reference stations (YB and CB) ranged from 0.45 to 18.08 ${\mu}$g/g of wet sediment with an average of 3.09 ${\mu}$g/g. West of Namhaedo (Stations Bl2-B33) generally showed much higher values than inner Kwangyang Bay and in Chinju Bay. Chinju Bay generally showed the lowest value among the study area. Subtidal bottom sediments in inner Kwangyang Bay and Chinju Bay seemed to be less affected than west of Namhaedo. Heavy metal concentrations in the sediment were relatively higher in the Kwangyang Bay than in the Chinju Bay. However, metal concentrations in the study area were in general comparable to the reference areas.

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Influence of Berseem and Lucerne Silages on Feed Intake, Nutrient Digestibility and Milk Yield in Lactating Nili Buffaloes

  • Sarwar, M.;Khan, M. Ajmal;Nisa, Mahr-un;Touqir, N.A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.4
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    • pp.475-478
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    • 2005
  • This study was conducted to evaluate feeding value of berseem and lucerne silage as a replacement for conventional fodder (berseem fodder) in lactating Nili buffaloes. Fifteen early lactating multi-parous Nili buffaloes, five buffaloes in each group were allotted three experimental diets. Berseem and lucerne fodders were ensiled at 30% DM (wheat straw was used to adjust the DM of fodders) with molasses (at the rate of 2% of fodder DM) in two bunker silos for 30 days. The diets contained 75% DM from berseem fodder (BF), 75% DM from berseem silage (BS) and 75% DM from lucerne silage (LS). Each diet contained 25% concentrate DM. Diets were mixed daily and fed twice a day at ad libitum intakes. Dry matter intake (DMI) was significantly higher (13.8 kg/d) in buffaloes fed BF diet than those fed LS (12.5 kg/d) and BS (11.9 kg/day) diets. The differences in digestible DMI and DMI as percent body weight were significant between fodder and silage based diets but non-significant when BS and LS were compared. Lower DMI with silage-based diets was probably because of low silage pH. Intake of NDF (NDFI) was higher (5.68 kg/d) in buffaloes fed BF diet followed by those fed LS (5.50 kg/d) and BS (5.00 kg/d) diets. The difference was significant (p<0.05) across fodder and silage based diets but NDFI was non-significant across both silage-based diets. The apparent DM digestibility was significantly different (p<0.05) between fodder and silage-based diets but was non-significant between LS and BS diets. Four percent fat corrected milk yield was significantly different (p<0.05) between fodder and silage-based diets but was non-significant between LS and BS diets. Higher milk yield with fodder based diet was because of more digestible nutrient intake (Table 3) compared with silage based diets. Milk CP, TP and NPN and SNF did not show any treatment effects. The present results indicated that the berseem and lucerne fodder ensiled at 30% DM level with 2% molasses could safely replace (75% DM) the conventional leguminous fodder in the diets of lactating Nili buffaloes.

Oil Absorptive Properties of Polypropylene Knit Fabric Treated with Oleophilic Acrylic Resin (친유성 아크릴 수지로 처리된 폴리프로필렌 편직물의 유흡착 성질)

  • Jeong, Hwa-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.2
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    • pp.528-535
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    • 2016
  • Two types of oleophilic acrylic prepolymers were prepared by the solution copolymerization of either ethyl acrylate (EA) or lauryl acrylate (LA) with hydroxy ethyl acrylate (HEA). For the formation of oil-absorbent materials, a mixed solution of the prepolymer and hexamethylene diisocyanate (HDI) as a cross-linker in toluene was applied to polypropylene knit velvet fabric through the conventional pad-dry-cure procedure. The gel fraction of the crosslinked resin, EA-HEA-HDI, increased with increasing feed ratio of HEA to total acrylate or HDI concentration. The oil absorbancy and retention ratio of the prepared materials were compared according to the add-on ratio of resin to fabric, and were assessed with n-decane, toluene, soybean oil, lubricant and bunker C oil as test oils. The optimal oil absorbancy of the materials were observed at around 6% of the add-on ratio for all these oils except for soybean oil. On the other hand, the oil retention ratio increased as the add-on ratio increased. Futhermore, heavier and more viscous oil generally showed higher oil retention ratios. In addition, the oil absorbancy of the materials treated with LA-HEA-HDI resin was higher than that treated with EA-HEA-HDI resin, which showed that the acrylic resins are more absorptive with increasing length of their side alkyl chain.

A Study on the Improvement of Dairy Rousing Systems in Kore (한국의 낙농시설 개선에 관한 연구)

  • Kim, Moon-Ki;Koh, Chae-Koon;Kim, H. U.
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.24 no.1
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    • pp.31-43
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    • 1982
  • Engineering phase of dairy housing systems has close connection with the milk produc- tivity of dairy cattle, the quality of milk, extension of dairy production systems, labor- saving in management of dairy cattle and the like. Moreover, the rate of investment of dairy housing facilities is of relatively high level, However, there has been almost no research effort for the improvement of engineering aspects of dairy housing systems in Korea. The purpose of this study is to find out general engineering problems and to recomm- end the improvement in dairy housing systems in Korea. Field survey by means of questionaire, direct measurements, taking pictures and sketching was conducted to get necessary information for the study. Kyung-ki Do region was firstly chosen for sampling area since it has included more than half of the number of dairy farms of the whole country. The results obtained are summarized as follows: 1. In overall dairy farm layout, the dwellings of workers were ignored in the light of sanitary environment 2. The layout of stalls in a dairy barn belongs mostly to the type of double-row face-out, which is compatible with the emphasis of manure disposal activities. 3. While the width and length of stalls were sufficiently close to the standard dimension, the width of mangers was much less than the standard dimension. 4. The width and depth of manure gutters and the width of working alleys were much. less than the standard dimension. 5. The mooring equipment was mostly in the classes of chain or rope. The watering equipment was not facilitated independantly except the one cese of using watercup. 6. The bucket milkers with one or two bucket milkers with the capacity of two cattles. each were used as milking equipment in most dairy farms. 7. There were only few milk rooms independently spaced from other space, in which the arrangement of milking equipment was much less than the standard condition. 8. The lounging ground area was averaged to be sufficient for the activity of dairy herd. 9. Silos for silage used during winter consisted of mostly bunker silos, trench silos and underground vertical silos. Ordinary vertical silos were considered for the farmers to be inconvenient for the labor saving. 10. From the view point of heat conservation and moisture removal within the dairy barns, windows were not flexible for the easy ventilation and ceiling part was not adequate for temperatur maintenance. 11. Waste treatment and disposal systems were not provided with most dairy farms, therefore the livestock waste pollution problems would be serious in the near future.

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Development of an Unmanned Conveyor Belt Recovery Skimmer for Floating Marine Debris and High Viscosity Oil (무인 컨베이어 벨트식 부유쓰레기 및 고점도유 회수장비 개발 연구)

  • Han, Sang-goo;Lee, Won-ju;Jang, Se-hyun;Choi, Jae-hyuk
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.23 no.2
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    • pp.208-215
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    • 2017
  • When persistent oil, such as crude oil or Bunker C oil, is spilled at sea, viscosity increases through the weathering process. Equipment that can collect this oil when mixed with floating marine debris is very limited. In this study, devices that can be attached to the outside of existing oil skimmers have been applied to the inside of the main body, to develop an unmanned conveyor belt type floating marine debris and high viscosity oil recovery skimmer, which is composed of a conveyor belt, a sweeper with a forced inflow device, and a collection tank equipped with a buoyant body. The resulting skimmer was operated at a speed of 1.2 knots at a distance of 30 m in a sea area test. It was stable when moving laterally in any direction. An oil recovery performance test was conducted using a portable storage tank, and oil was recovered from a minimum of $7.8k{\ell}/h$ to a maximum of $23.3k{\ell}/h$. Moreover, recovery of $7.7k{\ell}/h$ was obtained in a wave water tank test with floating marine debris such as PET bottles and oil mixed. If the equipment developed in this study was used in the field for oil pollution accidents, it could be expected to contribute to improved response capability. We believe our equipment could be used in further studies to improvement the performance of existing portable oil skimmers.

Experimental and Numerical Study of Berthing and Unberthing of LNG-Bunkering Vessels (실험 및 수치해석을 통한 LNG 벙커링 선박들의 이접안 안정성 평가 연구)

  • Jung, Sung-Jun;Oh, Seung-Hoon;Jung, Dong-Woo;Kim, Yun-Ho;Jung, Dong-Ho
    • Journal of Navigation and Port Research
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    • v.44 no.6
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    • pp.439-446
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    • 2020
  • The IMO has adopted emission standards through Annex VI of the International Convention for the Prevention of Pollution from Ships (MARPOL) that strictly prohibit the use of bunker C oil for vessels. In this study, we have adopted the turret-moored Floating LNG-Bunkering Terminal (FLBT) which is designed to receive the LNG from LNGCs and transfer it to LNG-bunkering shuttles in side-by-side moored condition. Numerical analyses were carried out using the high-order boundary-element method for four vessels at various relative distances. Mean wave drift forces were compared in an operational sea state. A model test was performed in the ocean engineering basin at the Korea Research Institute of Ships & Ocean Engineering (KRISO) to verify the safety of the berthing/unberthing operation. In the model test, a jig was designed to simulate tug boats pushing or pulling the bunkering vessels, so that the friction force of the g operation was not affected. Safety depended on the environmental direction, with more stable operation possible if the heading-control function of FLBT is applied to avoid beam-sea conditions.

Analysis of Factors Affecting on the Freight Rate of Container Carriers (컨테이너 운임에 미치는 영향요인 분석)

  • Ahn, Young-Gyun;Ko, Byoung-Wook
    • Korea Trade Review
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    • v.43 no.5
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    • pp.159-177
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    • 2018
  • The container shipping sector is an important international logistics operation that connects open economies. Freight rates rapidly change as the market fluctuates, and staff related to the shipping market are interested in factors that determine freight rates in the container market. This study uses the Vector Error Correction Model(VECM) to estimate the impact of factors affecting container freight rates. This study uses data published by Clarksons. The analysis results show a 4.2% increase in freight rates when world container traffic increases at 1.0%, a 4.0% decrease in freight rates when volume of container carriers increases by 1.0%, a 0.07% increase in freight rates when bunker price increases by 1.0%, and a 0.04% increase in freight rates accompanying 1.0% increase in libor interests rates. In addition, if the current freight rate is 1.0% higher than the long-term equilibrium rate, the freight rate will be reduced by 3.2% in the subsequent term. In addition, if the current freight rate is 1.0% lower than the long-term equilibrium rate, the freight rate will decrease by 0.12% in the following term. However, the adjusting power in a period of recession is not statistically significant which means that the pressure of freight rate increase in this case is neglectable. This research is expected to contribute to the utilization of scientific methods in forecasting container freight rates.

Factor Analysis Affecting on the Charterage of Capesize Bulk Carriers (케이프사이즈 용선료에 미치는 영향 요인분석)

  • Ahn, Young-Gyun;Lee, Min-Kyu
    • Korea Trade Review
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    • v.43 no.3
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    • pp.125-145
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    • 2018
  • The Baltic Shipping Exchange is reporting the Baltic Dry Index (BDI) which represents the average charter rate for bulk carriers transporting major cargoes such as iron ore, coal, grain, and so on. And the current BDI index is reflected in the proportion of capesize 40%, panamax 30% and spramax 30%. Like mentioned above, the capesize plays a major role among the various sizes of bulk carriers and this study is to analyze the influence of the factors influencing on charter rate of capesize carriers which transport iron ore and coal as the major cargoes. For this purpose, this study verified causality between variables using Vector Error Correction Model (VECM) and tried to derive a long-run equilibrium model between the dependent variable and independent variables. Regression analysis showed that every six independent variable has a significant effect on the capesize charter rate, even at the 1% level of significance. Charter rate decreases by 0.08% when capesize total fleet increases by 1%, charter rate increases by 0.04% when bunker oil price increases by 1%, and charter rate decreases by 0.01% when Yen/Dollar rate increases by 1%. And charter rate increases by 0.02% when global GDP increases by one unit (1%). In addition, the increase in cargo volume of iron ore and coal which are major transportation items of capesize carriers has also been shown to increase charter rates. Charter rate increases by 0.11% in case of 1% increase in iron ore cargo volume, and 0.09% in case of 1% increase in coal cargo volume. Although there have been some studies to analyze the influence of factors affecting the charterage of bulk carriers in the past, there have been few studies on the analysis of specific size vessels. At present moment when ship size is getting bigger, this study carried out research on capesize vessels, which are biggest among bulk carriers, and whose utilization is continuously increasing. This study is also expected to contribute to the establishment of trade policies for specific cargoes such as iron ore and coal.

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Studies on Dairy Farming Status, Reproductive Efficiencies and Disorders in New Zealand (I) A Survey on Dairy Farming Status and Milk Yield in Palmerston North Area (뉴질랜드 (Palmerston North) 의 낙농 현황과 번식 및 번식장해에 관한 연구(I) Palmerston North 지역의 낙농 현황과 우유 생산량에 관한 조사 연구)

  • 김중계;맥도날드
    • Korean Journal of Animal Reproduction
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    • v.24 no.1
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    • pp.1-18
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    • 2000
  • Eighty dairy farms in Palmers ton North area in New Zealand were surveyed on 1) general characteristics (10 Questions), 2) milk yield and feed supplementary (7 questions), 3) reproductive efficiencies (12 questions) and 4) reproductive disorders (12 questions) by mail questions from February to July, 1998. Among those 4 items from 38 dairy farms (47.5%), especially in items 1) and 2), overall dairy farming situation, supplementary feeding and milk yields were surveyed and analyzed for Korean dairy farmers (especially in Cheju island) to have better understanding or higher economical gains. The results were as follows. 1. In dairy experience, 21 (45%) among 38 dairy farms surveyed were answered that farming less than 15 years, 15~19 year, 20~25 years and over 26 years experience were 3 (7.9%), 7 (18.4%), 6 (15.8%) and 5 (13.2%) which generally showed longer experience compare to Korean dairy farming situation. In survey of labour input and business goal of dairy farming, self-managing farms, sharemilkers, unpaid family manpowering farms, manager running farms, farms with hired worker, farms with part time helper and other type was 21 (55.3%), 10 (26.3%), 2 (3.5%), 3 (5.3%), 18 (31.6%), 2 (3.5%), and 1 (1.8%), respectively. 2. Analyzing pasture and tillable land, pasture according to feeding scale (200, 300 and 400 heads) were 56, 90 and 165.3 ha, and tillable lands were 51, 78 and 165 ha which showed some differences among feeding scale. In recording methods in 38 farms replied, 36 (95%) dairy handbook and 23 (70%) dual methods taking farms were higher than that of 10 (26.3%) computer and 15(39.5%) well-recorder methods. 3. Dairy waste processing facilities in environmental field were almost perfect except of metropolitan area, and so no problem was developed in its control so far. Hence, 26 farm (68.4%) of pond system was higher rather than those in 8 (21.2%) of using as organic manure after storing feces of dairy cattle, 1(2.6%) bunker system and 3 (7.9%) other type farms. 4. In milking facilities, 33 farms (86.9%) of Harringbone types were higher than those in 3 (7.9%) of Walkthrough types, 1 (2.6%) of Rotary system and other types. Although the construction facilities was not enough, this system show the world-leveled dairy country to attempted to elevate economic gains using the advantage of climatic condition. 5. In milking day and yearly yield per head, average 275 milking days and 87 drying days were longer than that of 228 average milking days in New Zealand. Annual total milk yield per head and milk solid (ms) was 3,990 kg and approximately 319 kg. Dairy milk solid (ms) per head, milk yield, fat percentage was 1.2 kg, 15.5 kg and average 4.83% which was much higher than in other country, and milk protein was average 3.75%. 6. In coclusion, Palmerstone North has been a center of dairy farming in New Zealand for the last 21 years. Their dairy farming history is 6~9 year longer than ours and the average number of milking cows per farm is 355, which is much greater than that (35) of Korea. They do not have dairy barn, but only milking parlors. Cows are taken care of by family 0.5 persons), are on a planned calving schedule in spring (93%) and milked for 240~280 days a year, avoiding winter. Cows are dried according to milk yield and body condition score. This management system is quite different from that of Korean dairy farms. Cows are not fed concentrates, relying entirely on pasture forages and the average milk yield per cow is 3,500 kg, which is about 1/2 milk yield of Korean dairy farms. They were bred to produce high fat milk with an average of 4.5%. Their milk production cost is the lowest in the world and the country's economy relies heavily on milk production. We Korean farmers may try to increase farming size, decreasing labor and management costs.

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