• The Journal of Engineering Geology
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• v.19 no.4
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• pp.433-439
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• 2009

The compressed packer device is designed to improve the underground contamination prevention facilities of ground water wells. As for the device, the installation is simple because of the safety lock device and the compression of the casing are simple the installation is simple. There is no leakage of ground water because the pressure resistance with $4.5\;kg/cm^2$ makes it equipped with the watertightness The single casing is installed and the reaming for grouting is possible with 300 mm excavation so that installation cost can be saved. Silicon rubber is used for the compressed packer so that the extension rate is 590%. In terms of environmental pollution, it is an environmental friendly product which does not contain harmful ingredients such as Pb, Cd, and phenol. below the standard or undetectable level Furthermore, the installation costs are 35 to 62% or lower than the conventional grouting construction method and are 87% or lower than the expansion packer construction method, the new environmental technology No.47 Also, the device is designed to meet the relevant regulations such as Rules on Preserving the Ground Water Quality, The Standard on Jeju Island Ground Water Development and Facility Installation and Management, and The Plan and Guideline on Operating and Managing the Small-Scale Tap Water Facilities of Ministry of Environment and Ministry of Food, Agriculture, Forestry and Fisheries.

• Journal of the Korean GEO-environmental Society
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• v.14 no.8
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• pp.37-44
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• 2013

The superiority of bearing ground anchor system has been recognized for the stability and economical efficiency since 1950s in Japan, Europe and etc. The ground anchor introduced in Korea, however, has the structural problem that the tensile strength comes only from the ground frictional force caused by the expansion of the wedge body and it is impossible to evaluate the bearing resistance because the adhering method of the anchor body to hollow wall is not appropriate. In this study, the underreamed ground anchor system was developed so that the bearing pressure of ground anchor can exert as much as possible. And the in-situ tests were performed to evaluate the pullout behavior characteristics and to verify the decreasing effect of the bonded length. The pullout tests were performed with the non-grouted tension condition and grouted tension condition in order to identify the pull-out resistance of each conditions. In addition, it was compared with the results of friction anchor. Finally, the numerical analysis was fulfilled to verify the bearing effect at the bonded part through the detailed modeling by PLAXIS-2D, which is general finite element method analysis program.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.58.1-58.1
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• 2010

In solar cell module manufacturing, single solar cells has to be joined electrically to strings. Copper stripes coated with tin-silver-copper alloy are joined on screen printed silver of solar cells which is called busbar. The bus bar collects the electrons generated in solar cell and it is connected to the next cell in the conventional module manufacturing by a metal stringer using conventional hot air or infrared lamp soldering systems. For thin solar cells, both soldering methods have disadvantages, which heats up the whole cell to high temperatures. Because of the different thermal expansion coefficient, mechanical stresses are induced in the solar cell. Recently, the trend of solar cell is toward thinner thickness below 180um and thus the risk of breakage of solar cells is increasing. This has led to the demand for new joining processes with high productivity and reduced error rates. In our project, we have developed a new method to solder solar cells with a laser heating source. The soldering process using diode laser with wavelength of 980nm was examined. The diode laser used has a maximum power of 60W and a scanner system is used to solder dimension of 6" solar cell and the beam travel speed is optimized. For clamping copper stripe to solar cell, zirconia(ZrO)coated iron pin-spring system is used to clamp both joining parts during a scanner system is traveled. The hot plate temperature that solar cell is positioned during lasersoldering process is optimized. Also, conventional solder joints after $180^{\circ}C$ peel tests are compared to the laser soldering methods. Microstructures in welded zone shows that the diffusion zone between solar cell and metal stripes is better formed than inIR soldering method. It is analyzed that the laser solder joints show no damages to the silicon wafer and no cracks beneath the contact. Peel strength between 4N and 5N are measured, with much shorter joining time than IR solder joints and it is shown that the use of laser soldering reduced the degree of bending of solar cell much less than IR soldering.

• Cartoon and Animation Studies
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• s.37
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• pp.221-245
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• 2014

With the success of the world's first 3D computer animated film, "Toy Story" in 1995, industrial development of 3D computer animation gained considerable momentum. Consequently, various 3D animations for TV were produced; in addition, high quality 3D computer animation games became common. To save a large amount of 3D animation production time and cost, technological development has been conducted actively, in accordance with the expansion of industrial demand in this field. Further, compared with the traditional approach of producing animations through hand-drawings, the efficiency of producing 3D computer animations is infinitely greater. In this study, an experiment and a comparative analysis of markerless motion capture systems for facial expression animation has been conducted that aims to improve the efficiency of 3D computer animation production. Faceware system, which is a product of Image Metrics, provides sophisticated production tools despite the complexity of motion capture recognition and application process. Faceshift system, which is a product of same-named Faceshift, though relatively less sophisticated, provides applications for rapid real-time motion recognition. It is hoped that the results of the comparative analysis presented in this paper become baseline data for selecting the appropriate motion capture and key frame animation method for the most efficient production of facial expression animation in accordance with production time and cost, and the degree of sophistication and media in use, when creating animation.

• Applied Chemistry for Engineering
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• v.27 no.4
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• pp.444-448
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• 2016

Hollow silicon/carbon (H-Si/C) composites as anode materials for lithium ion batteries were investigated to overcome the large volume expansion. H-Si/C composites were prepared as follows; hollow $SiO_2\;(H-SiO_2)$ was prepared by adding $NaBH_4$ to $SiO_2$ synthesized using $st{\ddot{o}}ber$ method followed by magnesiothermic reduction and carbonization of phenolic resin. The H-Si/C composites were analyzed by XRD, SEM, BET and EDX. To improve the capacity and cycle performance, the electrochemical characteristics of H-Si/C composites synthesized with various $NaBH_4$ contents were investigated by charge/discharge, cycle, cyclic voltammetry and impedance tests. The coin cell using H-Si/C composite ($SiO_2:NaBH_4=1:1$ in weight) in the electrolyte of $LiPF_6$ dissolved in organic solvents (EC : DMC : EMC = 1 : 1 : 1 vol%) has better capacity (1459 mAh/g) than those of other composition coin cells. It is found that the coin cell ($SiO_2:NaBH_4=1:1$ in weight) has an excellent capacity retention from 2nd cycle to 40th cycle.

• Journal of Korean Society of Transportation
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• v.22 no.5
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• pp.139-149
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• 2004

As the expansion of road capacity has become impractical in many urban areas, congestion pricing has been widely considered as an effective method to reduce urban traffic congestion in recent years. The principal reason is that the congestion pricing may lead the user equilibrium (UE) flow pattern to system optimum (SO) pattern in road network. In the context of network equilibrium, the link tolls according to the marginal cost pricing principle can user an UE flow to a SO pattern. Thus, the pricing method offers an efficient tool for moving toward system optimal traffic conditions on the network. This paper proposes a continuous network design program (CNDP) in network equilibrium condition, in order to find optimal congestion toll for maximizing net economic benefit (NEB). The model could be formulated as a bi-level program with continuous variable(congestion toll) such that the upper level problem is for maximizing the NEB in elastic demand, while the lower level is for describing route choice of road users. The bi-level CNDP is intrinsically nonlinear, non-convex, and hence it might be difficult to solve. So, we suggest a heuristic solution algorithm, which adopt derivative information of link flow with respect to design parameter, or congestion toll. Two example networks are used for test of the model proposed in the paper.

• Food Science and Preservation
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• v.11 no.3
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• pp.325-330
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• 2004

This study was conducted to investigate optimal processing conditions, cooking characteristics, antioxidant activity and packaging method of rice coated with bamboo extract. In sensory evaluation of cooked rice, rice coated with bamboo ethanol extract was higher smell and taste than the other extraction methods, but texture showed no difference. As coating concentration increasing, L, a and b values of coated rice were increased. But L value of coated rice after cooking was decreased. On sensory evaluation of cooked rice, smell and taste were best in 10$\%$ coated with bamboo ethanol extract. Mineral contents of coated rice with bamboo extract were higher than those of uncoated. Water absorption and volume expansion of coated rice were lower than uncoated rice but showed higher toyo value. Hardness, gumminess and chewiness values of cooked rice with coated rice were higher than uncoated rice. Antioxidant activity of coated rice was higher than uncoated rice about twice times. Toyo values and alkali digestive values of coated rice were highest in paper package than the other packaging conditions. The total bacterial counts of rice coated with bamboo extract after cooking was lower than uncoated rice during storage at 25 and 6O$^{\circ}C$.

• Journal of the Korea Computer Graphics Society
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• v.14 no.4
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• pp.7-18
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• 2008

To realistically produce fluids such as smoke for the visual effects in the films or animations, we need two main processes: a physics-based modeling of smoke and a rendering of smoke simulation data, based on light transport theory. In the computer graphics community, the physics-based fluids simulation is generally adopted for smoke modeling. Recently, the interest of the particle-based Lagrangian simulation methods is increasing due to the advantages at simulation time, instead of the grid-based Eulerian simulation methods which was widely used. As a result, because the smoke rendering technique depends heavily on the modeling method, the research for rendering of the particle-based smoke data still remains challenging while the research for rendering of the grid-based smoke data is actively in progress. This paper focuses on realistic rendering technique for the smoke particles produced by Lagrangian simulation method. This paper introduces a technique which is called particle map, that is the expansion and modification of photon mapping technique for the particle data. And then, this paper suggests the novel particle map technique and shows the differences and improvements, compared to previous work. In addition, this paper presents irradiance map technique which is the pre-calculation of the multiple scattering term in the volume rendering equation to enhance efficiency at rendering time.

• Korean Journal of Construction Engineering and Management
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• v.17 no.2
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• pp.110-117
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• 2016

This paper shows procedure and strategies to improve military facilities and local residents' welfare through a civil-military sustainable cooperation project. Military installations tend to impede urban developments, so that a few civil compliant have been often filed. Meanwhile, it is sometimes impossible to relocate military units due to their own unique purpose, even though they belong to core sites of civil developments, which are generally indispensible due to urban expansion, magnified road networks and so on. The solution to offset these conflicts between civil and military demands, which are associated with military units and urbanization surrounding them, is to establish sustainable strategies which enable both civil and military be beneficial. In this study, it is described, decision making procedure to make some facilities of a military unit be better as well as promote local residents' welfare through securing high-quality sports facilities. Delphi-technique and Paired Comparison Method are used to collect civil and military opinions regarding sustainable agreements. As a case study, a civil military cooperation project between a military unit and a local government is introduced. With successful projects, it is expected that the better installations could lead positive images of a military unit, provide advanced athletic environments for both local residents and military personnels, and lessen defense cost to maintain them. Moreover, this project will go down as a paragon of civil military sustainable cooperation.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.12 no.3
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• pp.139-148
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• 2000

In this paper, the interaction of oblique incident waves with a bottom-mounted and fluid-filled flexible membrane structure is investigated in the frame of linear hydro-elastic theory. The static shape of a membrane structure containing the fluid of a specific density is initially unknown and must be calculated before the hydrodynamic analysis. To solve hydrodynamic problem, the fluid domain is divided into the inner and outer region. The inner solution based on discrete membrane dynamic model and simple-source distribution over the entire fluid boundaries is matched to the outer solution ba~ed on an eigenfunction expansion method. The numerical results were compared to a series of Ohyama's experimental results. The measured reflection and tran¬smission coefficients reasonably follow the trend of predicted values. Using the computer program developed, the performance of a bottom-mounted and fluid-filled flexible membrane strocture is tested with various system parameters (membrane shape, internal pressure, density ratio) and wave characteristics (wave frequencies, incident wave angle). It is found that a bottom-mounted and fluid-filled flexible membrane structure can be an effel;tive wave barrier if properly designed.