• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.12
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• pp.1018-1027
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• 2003

This study treats the analysis of the performance and the design of plume abatement wet/dry cooling tower with dry type heat exchanger using a numerical method. A two-dimensional analysis is performed using the finite volume method for mechanical draft counterflow and crossflow tower. For a coupling problem between water and air system, a turbulent two phase flow is considered. Effectiveness-NTU method is used for modeling of the dry type heat exchanger. The parameter change simulations of the outer wall shape, the relative flowrate of air, and attachment of an air mixer are performed to examine the effect on plume abatement. It is found that if the relative air flowrate ratio and the adequate air mixer type are chosen well in addition to the ratio of water to air flowrate, the loss of the cooling capacity and the additional cost are reduced and the plume is abated.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.389-394
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• 1993

Die making process is classified into design,manufacturing,polishing,assembly, and performance test. Die polishing is not a machining process by cutting edge of tool, but it is finishing by relative cutting movement under the surface contact between grinding particles and workpiece, and this process comprised 30~40% of total manufacturing hours. However, die polishing process is still performed by the skilled workers. Now a days, it is very difficult to secure skilled workers due to the hardworking environment and this situation will be getting worse in the future which has great difficulty of dies and molds industries.This process has the common problem on the elimination of tedious manual polishing among the tool making industries. Therefore this study is aimed at the development of an automatic polishing attachment which could be attached onthe spindle of CNC machine tool and controlled by the NC program data created by CAD/CAM system. As a result, this study will contribute the realization of automatic fine polishing process and improvement of quality level of dies and molds.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1514-1517
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• 2005

In recent years, as the demands of VBNS(Very high speed Backbone Network Service) and VDSL(Very high-data rate Digital Subscriber Line) increase, the development of kernel parts of optical communication such as PLC(Planar Light Circuit), Coupler, WDM elements increase. The alignment and the attachment technology are very important to fabricate the optical elements for communication. In this paper, the mechanism of rotational stage are studied. with the three different method and the results of them are applied to the design of the system. The performance test of resolution and travel is performed.

• Magazine of the Korean Society of Agricultural Engineers
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• v.11 no.4
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• pp.1803-1809
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• 1969

The newly designed mole drainage plower which is attached to tractor is tested for work capacity comparing with the pulling by man animal and winch. Besides. the effect of desalinization by the mole drainage in reclaimed tideland was observed. The results as obtained in this experiment are as follows: 1. The mole drainage plower of tractor attachment has higher work capacity by 3 to 5 times than that of winch 2. The suitable soil moisture content to carry out the layout of mole drains is from 21 to 25 percent. 3. The new design mole drainage plower requires th lowest cost as comparing with the other methods. 4. Carrying out the mole drainage in reclaimed tideland it is effective in desalinization from 2 to 3 times than the only use of irrigation water. 5. The reasonable depth and interval of mole drains may be 60cm and 3m respectively. 6. The desalinization by the mole drainage increases the yield of rice from 40 to 45 percent in reclaimed tideland.

• The Journal of Advanced Prosthodontics
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• v.3 no.1
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• pp.37-42
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• 2011

Partial edentulism has multiple implications in relation to function, esthetics and future rehabilitative treatment. This case report illustrates the management of a patient with extreme consequences of partial edentulism. The main clinical findings were unopposed remaining teeth, overeruption of the remaining teeth, loss of vertical dimension of occlusion, and significant disfigurement of the occlusal plane. Following the diagnostic procedure, a well-coordinated prosthodontic treatment involving liaison with other dental disciplines was indicated. The management involved an innovative combination of fixed and removable prostheses in conjunction with crown lengthening surgery and strategic implant placement. Series of provisional prostheses were applied to facilitate the transition to the final treatment.

• International Journal of Precision Engineering and Manufacturing
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• v.1 no.1
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• pp.22-32
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• 2000

This paper describes the development of a precision 3-component load cell with plate beams which may be used for measuring forces Fx, Fy and moment Mz simultaneously in industry. The equations to predict the bending strains on the surface of the beams under forces or moment are derived, the attachment location of strain gages of each sensor is determined, and 3-component load cell is carried out. It reveals that the rated strain calculated from the derived equations are good agreement with the results from Finite Element Method analysis.

• Journal of the korean Society of Automotive Engineers
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• v.14 no.3
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• pp.57-70
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• 1992

As automobile industry develope, design techniques to satisfy light weight and high efficiency in automobile parts is demanded. In this study modal analysis is performed using transfer matrix method to identify dynamic characteristics of exhaust system. It is estimated the theoretical transfer function by Pestel-Leckey method and the mode shapes in 3-D graphic. the validity of developed program is verified by comparing with the experimental results of exhaust system. Estimated modal parameters(natural frequency, vibrational mode, transfer function) are in accord with the experimental results. From the developed program, we can predict a location of the hanger which is determined by the lowest RMS value point, when displacement is given as an input at the engine side. We can find that attachment of spring modelled hanger at the hanger location bring vibration level down.

• Journal of Biosystems Engineering
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• v.23 no.3
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• pp.271-276
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• 1998

A gripper mechanical design using a pneumatic system was developed to successfully grip, hold, and release a seedling plug for transplanting it. The gripper comprised of two air cylinders and shovel-type fingers. The gripper can grasp and hold a seedling by sliding the two fingers attached to the two separate air-cylinders, mounted at an angle of 15$^{\circ}$ When releasing a plug, retraction of the fingers gives a seedling little attachment to the gripper. To prevent seedling from attaching to the fingers, press-plates were attached to the end of the gipper. Transplanting performance of the developed gripper was tested with cucumber seedlings at different soil moisture contents. Overall transplanting performance of developed gipper was higher than the performance of the previously developed gripper. Best transplanting result was achieved at medium level of soil moisture content.

• Journal of the Korean Society of Safety
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• v.23 no.4
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• pp.36-41
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• 2008

This report describes the analytical solution of back EMF for BLDC motor using numerical analysis of air gap flux density. The analysis of air gap flux density is the key to expect the performance of back EMF for the design of brushless motor. The numerical analysis and FEM analysis are performed to vary attachment of stator side or rotor side, radial flux magnetization or parallel flux magnetization, magnet arc angle in the condition of constant air gap. This results have more reliable data comparing with test result of the back EMF for 7 phase BLDC motor.

• Journal of the Korean Society of Costume
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• v.59 no.2
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• pp.101-110
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• 2009

This is a study regarding the development of cultural products with applied traditional Saekdong-image. The objective of this study is to develop unique cultural products which combine traditional korean images with modern feel by utilizing traditional Saekdong-image. Saekdong has been an object of deep attachment and regarded as a tool for expressing korean images from ancient times to the present. Chosun dynasty shows a wonderful growth of fashion not only in dress but also in such accessories as patchwork wrapping-cloth and Saekdong, which imply a lot on formation or color arrangement. Approximately 24 pieces of cultural products that can be used in daily life were created using Saekdong, including traffic or credit card cases, name card cases, pouches, coin purses, bags, Vest, teapot wrapping-cloth, brooch. After design plans were made for each works, natural dyes were used to dye(dip dyeing) the fabrics(cotton, silk, linen) by theme. In addition, the increased quality of the products will be a competitive edge in the world market where products compete with no national bounds.