• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.5 no.1
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• pp.33-37
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• 1975

The author has observed 64 films from M. P. D. syndrome cases taken in Dept. of Radiology, the Infirmary of Dental College, Seoul National University in 1974, and obtained the following results: 1. In M. P. D. syndrome, the ratio between the female and the male were 2:l. 2. The prevalenting age were aged 20, 30, 10, and 40 in decreasing order. 3. The incidence was 21.8% in the left side, 29% in the right, and 21% was bilaterally, which show the right most frequent. 4. The roentgenograms revealed variable findings in each case, but there were not recognized any significant differences.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.345-348
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• 2000

본 사례는 국내 APT 건설 현장에서 수행된 식스시그마 프로젝트에 대한 것으로 폐콘크리트 발생 저감 및 잔량발생에 영향을 미치는 주요 인자들을 파악하고 개선안을 도출하는 과정을 보였다. 프로젝트는 식스시그마의 방법론을 따라 정의, 측정, 분석, 개선, 관리의 절차에 따라 주요 변수를 규명하고 개선안을 찾아내는 식으로 진행되었다. 분석결과 폐콘크리트 발생을 줄이기 위해서는 첫째, 거푸집 시공 및 타설 프로세스를 개선하고 둘째, 압송관 및 펌프카 내 잔여 레미콘을 최소한으로 감소시키며 셋째, 최종적으로 남은 레미콘을 재활용할 수 있도록 하는 세가지로 요약되었다

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.879-882
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• 1997

This paper aims to clarify the effect of the sol-gel sintered alumina grain and the PbO content of binder on the performance of the vitrified alumina stone for superfinishing the ball bearing race with the vitrified alumina superfinishing stone. The main conclusions obtained were as follows. The stone that contain 8- 11% PbO in binder shows the highest grinding ratio, and increasing or decreasing the PbO contents causes lower grinding ratio. When superfinishing with the stone using the 45% fused alumina and 55% sol-gel sintered alumina grain, the grinding ratio becomes the best, the other ratio of grain contents shows lower performance. With increasing the bending strength of stone, the grinding ratio becomes larger. The roughness of the finished surface is the lowest in case of using the stone of the above mentioned conditions.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.607-610
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• 2002

As machines become smaller and faster multileaf foil bearings are used to overcome the problems with heat, friction and wear Systems with foil bearings do not need a separate system for lubrication. These bearings are self acting and are therefore green systems. Until now, there have been many studies on the structural and dynamical performances. Therefore the object of the present study is to predict the flow and structural characteristics by using the Fluid/structure interaction method. The increase in RPM led to the increase in pressure, temperature difference, maximum velocity, Mach number, shear stress and torque. In the case of 90,000 RPM effects such as choking led to a non-lineararity in the system. Also the effect of eccentricity ratio was observed and showed that eccentricity increased the maximum pressure and the density difference while decreasing the shear stress and torque.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.10a
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• pp.273-278
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• 1998

In this paper, basic micro-mechanical properties of unidirectional CFRP composite shell such as bonding strength, fiber volume fraction and void fraction are measured and tensile strength test is performed with a fixture. And then fracture surfaces are observed by SEM. In case of basic micro-mechanical properties, bonding strength is reduce with decreasing of radius of each ply in a shell for the effect of residual stress, fiber volume fraction is smaller than plate, and void fraction is vise versa. For these reason, tensile strength of shell is smaller than plate fabricated with same prepreg. For failure mode shell has many splitted part along its length, and it is assumed that this phenomenon is caused by the difference of bonding strength for residual stress.

• Journal of the Korean Society of Marine Environment & Safety
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• v.5 no.1
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• pp.79-93
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• 1999

By the IMF condition, tax revenues of local governments are decreasing, under these conditions, container tax take important proportion in financial resources in Pusan Metropolitan City. However the container tax have time limit until 2001, that is, purposeful tax. But after the creating container tax, the level of accomplishment is very insufficient. So for the activation of local economy, we need active study on the existence problem of container tax. Though the abolition of container tax item is frequently discussed in central government, If the worst case comes, namely the abrogation, it gives big damages to the financial management of Pusan Metropolitan City. Therefore the container tax should be existent for both residents and local government. Because the expansion rate of container tax is so rapid, it makes very critical contribution to the stability and sound condition of Pusan Metropolitan City's finances.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.04a
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• pp.374-381
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• 2003

In this study, the reduction schemes of ICRS(In-Cabinet Response Spectra), the main part of seismic safety qualification of old nuclear power plant(USI A-46 problem), are studied. To obtain accurate dynamic characteristics of cabinet structure, the cabinet structure modeled by frame model and its eigen analysis is performed. The three types of seismic retrofitting scenarios, such as 1) the installation of bracing, 2) installation of damper, 3) installation of tuned mass damper(TMD), are established and evaluated for the decreasing of ICRS. In the cases of 1) ＆ 2), since, the retrofitted structures show larger ICRS than that of original structure, the careful considerations are need in the application of these methods. Though, the case of TMD show the best retrofitting result, the tuning between the real structure and analysis model is estimated the essential step of retrofitting.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.347-354
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• 2006

In this paper, we work with steel circular tubes and propose analysis model which can consider local buckling that it has an effect on failure of steel structures and induce the relation between loading and deformation. First of all, in respect to axial symmetry local buckling, which is simplest case, elasto-plastic behavior acting only axial loads is object Therefore, it suggests analysis model for axial symmetry local buckling. And that is explainable the process from increasing internal force to decreasing passing maximum internal force. Besides, we induce the relation between the axial force and axial deformation.

• Journal of the Korea Society for Simulation
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• v.10 no.1
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• pp.51-62
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• 2001

For the productivity improvement, it is necessary to analyze problem of the system and evaluate alternative plans. But, it if hard to experiment and evaluate alternative plans in real existing system. Therefore, it is necessary to synthetically analyze and evaluate alternative plans using simulation and statistical analysis method. In this case study, as a simulation language, Promodel is used to compare and evaluate four alternatives which are considered to improve the productivity of an object system. The object system is constituted of a pretreatment line and a painting line. The purpose of this study is to analyze whether the decrease of the down time in pretreatment line can be effective to the productivity improve comparing with exiting system and other alternatives. The other purpose is to choose an alternative that has the best productivity improvement. The results of the simulation show that the possibility of improvement in productivity by decreasing the down time of pretreatment line. Two-Stage Bonferroni Procedure is used to choose the best alternative.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.19 no.3 s.31
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• pp.201-208
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• 2006

Object : In this study, the effect of herbal external therapy, aromatherapy, herb medication against atopic dermatitis was investigated. Method : Atopic dermatitis grade and the effect of medication was determined using Kunz type and SCORAD index. Atopic dermatitos lesion was checked by taking pictures Result : The patient's admission SCORAD index was 74.2 but during 32 days admission treatment the patients's symptoms are getting reduced. At last when she discharged, the SCORAD index was 16.1. Conclusion : In this study, herbal external therapy, aromatherapy and herb medication were shown to treat atopic dermatitis effectively by decreasing itching, oozing, crust, dryness, lichenification. It is very possible that external therapy can offer a valuable mode of the treatment of not only atopic dermatitis but also another eczema.