• Journal of Environmental Science International
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• v.19 no.11
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• pp.1423-1436
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• 2010

The effects of meteorological and reclaiming conditions on the reduction of suspended particles are investigated using a computational fluid dynamics (CFD) model with the k-$\varepsilon$ turbulence closure scheme based on the renormalization group (RNG) theory. Twelve numerical experiments with different meteorological and reclaiming conditions are performed. For identifying the meteorological characteristics of the target area and providing the inflow conditions of the CFD model, the observed data from the automatic weather station (AWS) near the target area is analyzed. Complicated flow patterns such as flow distortion, horse-shoe vortex, recirculation zone, and channeling flow appeared due to the topography and buildings in the domain. Specially, the flow characteristics around the reclamation area are affected by the reclaiming height, reclaiming size and windbreak height. Reclaiming height affected the wind speed above the reclaiming area. Windbreak induces more complicated flow patterns around the reclaiming area as well as within the reclaiming area. In front of the windbreak, flow is distorted as it impinges on the windbreak. As a result, upward flow is generated there. Behind the windbreak, a secondary circulation, so called, a recirculation zone is generated and flow is reattached at the end of the recirculation zone (reattachment point). At the lower part of the recirculation zone, there is a reverse flow toward the windbreak. Flow passing to the reattachment point starts to be recovered. Total amounts of suspended particles are calculated using the frictional and threshold frictional velocities, erosion potential function, and the number of surface disturbance. In the case of a 10 m-reclaiming and northerly wind, the amount of suspended particles is largest. In the presence of 5 m windbreak, the friction velocity above the reclaiming area is largely reduced. As a result, the total amount of the suspended particles largely decreases, compared to the case with the same reclaiming and meteorological conditions except for the windbreak The calculated suspended particle amounts are used as the emission rate of the dispersion model simulations and the dispersion characteristics of the suspended particles are analyzed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.661-665
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• 1996

An inverse kinemetics problem of a reclaimer which digs and transports ironstones or coals in the raw yard is investigated. Because of the special features of the reclaimer of which scooping buckets are attached around the rotating drum at the end of boom, kinematic redundancy occurs in determining the joint varialbes For a given reclaiming point in space the forward kinematics yields 3 equations, however the number of involved variables in the equations are four. A plane equation approximating the surface near a reclaiming point is obtained by considering 8 adjacent points surrounding the reclaiming point. One extra equation to overcome redunduncyis further obtained from the condition that the normal vector at a reclaiming point is perpendicular to the plane. An approximate solution for a simplified problem is first discussed, Numerical solution for the oritinal nonlinear porblem with a constraint equation is also investigated. Finally a closed form solution which is not exact but sufficiently close enough is proposed by exploiting geometric constraint.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.296-299
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• 2001

Data on the oil spill recovery from the water surface by light floating electromagnetic plants using a new magnetic adsorbent are given. The feasibility scope for further oil recovery from such gathered mixtures(oil + adsorbent), reuse of this magnetic adsorbent and its property reclaiming and recycling were shown. The basic conception of the oil spill recovery and efficiency of this method were set forth.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.296-299
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• 2001

Data on the oil spill recovery from the water surface by light floating electromagnetic plants using a new magnetic adsorbent are given. The feasibility scope for further oil recovery from such gathered mixtures(oil+adsorbent), reuse of this magnetic adsorbent and its properly reclaiming and recycling were shown. The basic conception of the oil spill recovery and efficiency of this method were set forth.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.37-43
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• 1996

The high Temperatures and long residence times in the combustion zones of cement kiln can use to burn liquid and solid wastes, such as fuel-wastes, sludges and tire-wastes. To the lastest time, treatment methods of industrial waste are incineration treatment, ocean dumping and land dumping. These are the main methods, but all of them may cause vatious kinds of secondary pollution, including air pollution and water pollution. From this point of view, to reuse the Reclaiming-Fuel in Cement Kiln is the most outstanding waste treatment plant in the world and dose not cause any pollution at all.

• Resources Recycling
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• v.10 no.3
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• pp.43-50
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• 2001

Characteristics of crushing and magnetic separation on the spent batteries, were investigated for reclaiming spent carbon-zinc and alkaline manganese dioxide batteries. Crushing of carbon zinc battery was easier than that of alkaline $MnO_2$battery using impact type crusher with rotary blades. Most of magnetic products were distributed in the range of 8 mesh size. With crushing 1 ton of spent carbon-zinc and alkaline $MnO_2$batteries respectively, magnetic separation of 8 mesh oversize particles, we can get 214 kg and 235 kg of magnetic products which is composed of 94% and 88% of Fe.

• Journal of Environmental Science International
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• v.26 no.4
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• pp.457-466
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• 2017

The extensive construction works of container terminals progressed since 2006 was converted to small scaled construction works or reclaiming works since 2012 in Busan New Port area. To investigate changes in activity of otters with the change of construction work scales, the linear densities of spraints at 15 localities of 5 areas (I-V) near the Busan New Port construction areas were surveyed during the period from 2012 to 2016. As the results, the average linear density of spraints has a tendency to increase since 2014. That is, the linear densities of spraints have increased at the area II and IV where the reclaiming works have been progressed, although have decreased or unchanged in the areas I, III and V where small scaled construction works have been progressed. Based on the fact that there were habitats at the Honamdo in the area II and the Yeondo in the area IV, otters seemed to restore their activities around the habitats as the center regardless of the reclaiming works.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.1
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• pp.75-80
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• 2008

A scrapped fiber-reinforced plastic(FRP) fishing vessel causes many environmental problems, because technology development for recycling FRP vessel has not been adequately addressed. FRP is a main material for constructing a small coastal fishing vessel that is an object of reduction policy. Therefore, the FRP wastes derived a scrapped fishing vessel are increasing. In this study, I investigated an effective disposal process for FRP through the analysis of the actual conditions of scrapped FRP fishing vessel. The treatment processes of scrapped FRP fishing vessel are carried out with oil-removing, dismantling, intermediated processing(crushing), and then reclaiming follows burning in the final processing in Korea. However, in Japan, several recycling methods have been developed, for example, the incineration including thermal recovery, the use of cement-reclamation, and the use of asphalt concrete aggregate, because the method of reclaiming after incinerating which is generally used in Korea produces a toxic by-product such as dioxin.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.555-558
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• 2003

This study carried out to analyze the characteristics of water concentration for Saemangeum reclaiming area during two seasons. Total nitrogen appeared by thing which all mean values are the biggest at two survey at ST.4 that is near with Mangyoung river. At the same time, change by range of tide was seen. Therefore, is thought that ST.4 suffers impact of river and seawater at the same time. But is thought that water of Mangyoung river exerts bigger effect than seawater because ST.4 appears that concentration is high clearly with different Sampling point. Therefore, is thought that pollution occurs better than different sampling point if ST.4's flowing deters.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.5
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• pp.469-475
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• 1997

A method for solving the inverse kinematic problem of reclaimer is presented in this paper. The reclaimers in the raw yard are being used to dig raws and transfer them to the blast furnaces. The kinematic configuration of the reclaimer is different from that of commercially available robots, because it has a rotating disk with several buckets at the end of the boom to dig raws. The reclaimer has a redundancy due to the rotating disk : the degrees of freedom are greater than the number of forward kinematic equations. A plane equation in the 3-dimensional space is determined by using several points adjacent to the reclaiming point of the raw ores pile. A constraint is obtained from the relation ship of the plane equation and trajectories of the bucket of the reclaimer. Finally, a solution of the inverse kinematics of the reclaimer is determined by a numerical method.