• Special Issue of the Society of Naval Architects of Korea
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• 2015.09a
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• pp.85-92
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• 2015

In general, when ships are designed, structural strength and fatigue strength must be verified based on the relative rules respectively. In case of Slurry Iron Sand Carrier designed to carry Iron-Sand saturated at water content, there is no special consideration of fatigue strength analysis. However, this vessel is similar to Ore Carrier in consideration of the overall characteristics of loaded cargo and the shape of cargo hold. Therefore we verified fatigue strength based on fatigue analysis procedure of ore carrier in DNV Rules and carried out the study for improving of fatigue strength of Slurry Iron Sand Carrier.

• Bulletin of the Society of Naval Architects of Korea
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• v.53 no.2
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• pp.42-49
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• 2016

• Journal of Korean Society on Water Environment
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• v.31 no.2
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• pp.209-215
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• 2015

The purpose of this study is to evaluate the characteristic of the iron oxide carrier for removing arsenic contained in the groundwater. 4 types of iron oxide carrier used in the study is iron oxide coated sand carrier (IOCSC), iron oxide coated zeolite carrier (IOCZC), iron oxide plasticity carrier (IOPC) and platinum iron oxide plasticity carrier (PIOPC). The results of this study, IOPC is showed high arsenic adsorption strength and the maximum amount of adsorption than the IOCC. Based on the results of the arsenic adsorption characteristic, by using IOCC was conducted to column test. As a result, PIOPC is showed a high arsenic adsorption amount than IOPC, it was found that the time required to reach the breakthrough point is also extended. Therefore it is determined that stably compliance with water quality standards enhanced drinking water when using the PIOPC.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.5
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• pp.439-445
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• 2012

Only the sand carriers fitted with hopper doors can remove their hatch covers in current regulations. However, there is no sand carriers fitted with hopper doors in korea. Through the analysis of accidents, inspection of equipment installed on ships, and evaluation of stability and seakeeping performance concerning the sand carriers, it is expected that the current exemption requirement is modified for hatch covers for sand carriers. As the result, this paper proposed the removal of hatch covers and be fitted by tarpaulin instead to protect water ingress into the holds. This can be done by making the holds smaller designed to be filled full until the top of the hold without exceeding loadline. Also, the bilge pumps should have the sufficient capacity of pumping water out in the early stage of sand-water mixture to wetted condition in approximately 1 hour and be operationally ready in every voyage conditions.

• Computers and Concrete
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• v.21 no.2
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• pp.139-147
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• 2018

Due to enhanced construction requirement, ready mixed concrete are being popular day by day. The current study aimed to develop ready mixed concrete using GBFS contained cement and determine its properties of fresh and hardened states. A real scale experiment was set up in a ready mixed plant for measuring workability and compressive strength. The workability was tested after mixing (within 5 minutes), 30, 60, 90, 120 and 150 minutes of the running of bulk carrier. The ready mixed carrier employed spinning motion i.e., rotating around its axis with 20 RPM and running on road with 1km/h speed. The mixing ratio of cement: sand:gravel, water to cement ratio, super plasticizer were, 1:1.73:2.47, 0.40 and 6% of cement, respectively. The chemical composition of raw material was determined using XRF and the properties of cements were measured according to ASTM standards. The experimental results confirm that the cement with composition of 6.89% of GBFS, 4% of Gypsum and 89.11% of clinker showed the good compressive strength and workability of concrete after 150 minutes of the spinning motion in bulk carrier.

• Clean Technology
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• v.29 no.3
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• pp.185-192
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• 2023

This study was conducted to obtain basic process simulation data before conducting pyrolysis experiments for the development of a thermochemical conversion system by recirculation of heat carrier and gases thereby. In this study, polypropylene (PP) was used as a pyrolysis sample material as an alternative to waste plastics, and fluid sand was used as a heat transfer medium in the system. Manganese (Mn) was chosen as the catalyst for the pyrolysis experiment, and the catalyst pyrolysis was performed by impregnating it in the sand. The basic properties of PP were analyzed using a thermogravimetric analyzer (TGA), and liquid oil was generated through catalytic pyrolysis under a nitrogen atmosphere at 600℃. The carbon number distribution of the generated liquid oil was confirmed by GC/MS analysis. In this study, the effects of the presence and the amount of Mn loading on the yield of liquid oil and the distribution of hydrocarbons in the oil were investigated. When Mn/sand was used, the residue decreased and the oil yield increased compared to pyrolysis using sand alone. In addition, as the Mn loading increased, the ratio of C₆~C₉ range gasoline in the liquid oil gradually increased, and the distribution of diesel and heavy oil with more carbon atoms than C₁₀ in the oil decreased. In conclusion, it was found that using Mn as a catalyst and changing the amount of Mn could increase the yield of liquid oil and increase the gasoline ratio in the product.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.5
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• pp.469-490
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• 2003

Atmospheric concentrations of persistent organic pollutants (POPs) were measured at Gosan, Jeju in November 2001 and spring 2002, each time for two weeks. Primary target pollutants were organochlorine pesticides, coplanar polychlorinated biphenyls (co- PCBs), and dioxin/furans listed in the Stockholm Convention adopted in May 2001. Polycyclic aromatic hydrocarbons (PAHs) were also measured in order to understand the overall characteristics of the POPs distribution as well as PM$_{2.5}$, a potent carrier of POPs. In the latter part of the measurement period of November 2001, almost every pollutant of combustion origin including dioxin/furans went high probably due to influence of emissions in the nearby area. The characteristics of atmospheric environment at Gosan in this period were rather close to urban areas far from those of a background area. A severe dust storm swept for three days at the end of the measurement period of spring 2002. However, changes in pollutant concentrations were relatively small except PM$_{10}$. Nevertheless, increases in particulate PAHs and OCDD (octachlorinated dibenzo-p-dioxins), mostly present in fine particles, were observed. Trends in organochlorine pesticide variations were mixed although possible volatilization of DDT residues from soil was inferred from the measurements of spring 2002.2.2.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.462-473
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• 2019

The effects of the location and dimension of the gate, location, and volume of the feeder, application of a chill, chill volume, and heating method of the feeder with respect to the effect of the mold-designing technologies on the defect status of the products are described. It is possible to increase the solidification time of the feeder by heating feeder. Furthermore, the pressure generated from the feeder is imposed on a product, and this decreases the generation of shrinkage porosities. In this study, two types of gating and feeding systems had been proposed: the bottom L-type junctions and the top L-type junctions. Additionally, solidification behaviors, such as solidification time, shrinkage porosities, weight percentage of chill system to product, hot spot, and solidification time ratio (=Solidification time of feeder/solidification time of product), are extensively analyzed by using commercial casting simulation software. Based on the solidification behaviors, reasonable mold design, feeding system, critical feeder heating temperature, and solidification time ratios are proposed in the sand casting process for the fabrication of carrier housing in order to reduce the casting defects and to increase the recovery rate.

• Current Research on Agriculture and Life Sciences
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• v.2
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• pp.56-62
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• 1984

This experiment was carried out to investigate the effects of distilled water, pH, uv-irradiation, carrier, emulsifier and organic solvent on the stability of butachlor formulations in the course of storage. The uv-irradiation increased the decomposition rate of butachlor formulations in the order of emulsifiable concentrate, sand coated granular and zeolite adsorbed granular. Decomposition of butachlor emulsion was not affected by water and pH. Decomposition of butachlor emulsifiable concentrate which were prepared with various organic solvents at $50^{\circ}C$ was higher in the polar organic solvents than in the non-polar organic solvent. Decomposition of butachlor-emulsifiable concentrate emulsified in Tween-60 was higher than in Hy-620C or Newkalgen-MC.

• Culinary science and hospitality research
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• v.3
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• pp.271-289
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• 1997

The purpose of this study is to investigate previous data and possibility of the new culture building, insuring substantiality of the education in junior college, increasing of practical carrier, acquiring the money for practical class, and the direction of demand for education in a high level of industrial society. There's two parts to consist of investigation and the model case in wedding business in Junior college. The research groups in one part consist of 277 students in Junior college. The result were as follows: 1) The students would like to get the wedding business in new culture building. (72%) 2) The student shave got a idea to recommend to use the wedding facilities for their for their relative sand friends. (51%) 3) The trend of selecting in wedding facilities is outside than inside of facilities. (75%) 4) They would like to have the buffet service after wedding celemony, not a la carte for choose the meal. The above research data suggest that if the wedding facility's management would be accept, we could have expectation about development of junior college, emphasis of practical education and good wedding culture in this areas. For the most of student, they has a righ hand to manage the wedding facility in their college. First, the culinary students could have an experience of service practies to the customer in wedding celemony, as the result of training will be great. Second, the college could show their vision and hope to customer to interest it. Third, it can be supplied the right wedding culture and the wedding facilities which is low price and good circumstance for wedding. Fourth, it's very resonable to use the culture facilities during no class, Saturday and Sunday. Fifth, income from business can be used only a scholarship and a community development. Sixth, it can be induced the self-participication and motivation to take up a positive attitude for their life.