• Journal of the Korean Society for Precision Engineering
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• v.20 no.10
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• pp.31-40
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• 2003

In this paper, optimal cutting condition to minimize the form error in side wall machining with a flat end mill is studied. Cutting forces and tool deflection are calculated considering surface shape generated by the previous cutting such as roughing. Using the form error prediction method from tool deflection, optimal cutting condition considering form accuracy is investigated. Also, the effects of tool teeth number, tool geometry and cutting conditions on form error are analyzed. The characteristics and the difference of generated surface shape in up and down milling are discussed and over-cut free condition in up milling is presented. Form error reduction method through successive up and down milling is also suggested. The effectiveness and usefulness of the presented method are verified from a series of cutting experiments under various cutting conditions. It is confirmed that form error prediction from tool deflection in side wall machining can be used in optimal cutting condition selection and real time surface error simulation for CAD/CAM systems. This study also contributes to cutting process optimization for the improvement of form accuracy especially in precision die and mold manufacturing.

• Journal of Korean Society of Transportation
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• v.29 no.2
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• pp.7-14
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• 2011

This paper discusses operational technique and effectiveness of Variable Speed Limits system that is implemented to control the traffic-flow on the Naebu Expressway. As the first step of the analysis, traffic data collected from vehicle detectors are corrected and smoothed. Applying a pattern analysis technique to the traffic data, the weekday traffic is classified into four different groups, and median of each group is calculated. Using three state variables, i.e., diverted traffic volume, average density and average speed, the conditions of roadway segments are determined. Computational outputs resulted from the application of the proposed model to the scenarios show that implementation of Variable Speed Limits system improved both safety and efficiency of the expressway. For the operational strategy, this paper also presents the change rate of the speed limit, and the effective duration of the speed limit according to the entering traffic volume.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.5
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• pp.324-329
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• 2008

A coal mine drainage sludge(designated as CMDS) is mainly generated during physicochemical treatment or electrical purification of the drainage abandoned mine that include dissolved heavy metal. To understand the possibility of an application of the dehydrated CMDS as the landfill cover medium of hygienic a reclaimed ground, an laboratory experiment was performed to investigate the physicochemical and geoengineering characteristics of the dehydrated CMDS. To improve the geoengineering characteristics of the dehydrated CMDS, the liquid limit, plasticity limit test, compaction method test, strength test, and hydraulic conductivity test ware performed with the lithification material mixed sludge. When the mixed ratio of the sludge and the lithification material was more than 1:06, the compaction method was A method, the moisture content less than 33.5%, the strength of mixed sludge was $8.2kg\;cm^{-2}$, the hydraulic conductivity was $2.7\times10^{-6}cm\;sec^{-1}$, the sludge was up to the landfill standard of US Environmental Protection Agency (US EPA).

• Journal of the korean veterinary medical association
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• v.28 no.6
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• pp.321-329
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• 1992

'주' 필자는 최근(1992년 3월 5일$\~$30일)에, 한일공동 연구사업 수행을 위하여 일본정부 과학기술청의 <개별 전문가 초청계획>에 의한 초청을 받아 일본 농림수산성 가축위생시험장을 다녀왔다. 본래, 일본에 가게된 주 목적은 '소 타일레리아병에 관한 병원학적 비교연구'이었으며, 진드기 체내 및 우체내에 있어서의 타일레리아 원충의 발육단계별 정밀진단과 정제백신 개발을 위한 생물공학적 기술응용 연구가 주요 과제내용이었다. 마침, 제 113회 일본 수의학회 학술대회(1992년 4월 2일$\~$4일)의 개최가 예정되어 있었고, 이 학회의 <기생충학 분과회 심포지움>의 주제가 '톱밥 축사에 있어서의 새로운 선충성 질병'이었으며, 그 심포지움의 대장으로 예정되어 있는 평 조형 박사(일본 농림수산성 가축위생시험장 기생충연구실 실장)및 공동연구자 중촌의남 박사 등과 접촉하여 연구실 견학 및 토의를 할 수 있는 기회를 가진 바 있으며(사진 참조), 관련된 최신문헌을 입수한 바 있다. 본 편에서는, 최근에 일본에서 새로운 기생충성 질병으로 문제시 되고 있는 '송아지 돌연사'와 관련하여, 그 병원체인 유두분선충(Strongyloides papilosus)의 감염피해 실태와 인공감염시험 결과 등에 대하여 금년도 일본수의학회 기생충학 분과회 심포지움 주제발표 내용을 중심으로 하여 해설을 드리고 한편, 유두분선충증의 병원체 및 생활환모형, 감염역학과 감염성립조건, 진단 및 치료대책, 향후 연구문제와 전망 등에 대하여 함께 고찰해 보고자 한다.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.912-917
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• 2003

In this paper a new truss modeling technique for describing the beam shear resistance mechanism is proposed based on the reinterpretation of the well-known relationship between shear and the rate of change of bending moment in a reinforced concrete beam subjected to combined shear and moment loads. The core of the model is that a new perspective on the shear resistance can be gained by viewing the internal stress filed in terms of the superposition of two base components of shear resistance; arch action and beam action. The arch action can be described as a simple tied-arch which is consisted of a curved compression chord and a tension tie of the longitudinal steel, while the beam action between the two chords can be modeled as a membrane shearing element with forming a smeared truss action. The compatibility of deformation associated to the two action is taken into account by employing an experimental factor or internal state force factor a. Then the base equation of V=dM/dx is numerically duplicated. The new model was examined by the 362 experimental results. The shear strength predicted by the internal force state factor a show better correlation with the tested values than the present shear design.

• Korean Journal of Ichthyology
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• v.13 no.1
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• pp.1-5
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• 2001

Taxonomic review of Cobitis laterimaculata was carried out based on 17 specimens collected from the Caozejiang River, Huangzezhen, Shengxian county, Zhejiang province, China. The species shares several notable characters with Niwaella spp., including the posterior position of the dorsal fin, small head, color pattern without pigmentary zones of Gambetta, short and curved suborbital spine, short and subequal barbels, strong carina on caudal peduncle, and lack of a lamina circularis on the pectoral fin base in males. We conclude that Cobitis laterimaculata should be transferred from Cobitis to Niwaella.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.10 no.2
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• pp.15-21
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• 2012

Purpose : The purpose of this study is to compare the rehabilitation effects of hydrotherapy and Bobath therapy. Methods : The study was performed with patients of hemiparesis caused by cerebral stroke. The participants were divided into two groups based on random sampling method. One group received hydrotherapy while the other received Bobath therapy. Each rehabilitation program lasted 40 minutes a day, 5 days a week, for 6 weeks. Pertinent indicators-Berg's balance scale (BBS), gait parameter, and static balance analysis-were recorded before andafter the programs, as well as every 2 weeks during the rehabilitation programs Results : There was showed a significantly increase of BBS score. Static open and close showed statistically significant in interaction by time and groups. There was significant differences of gait velocity. Conclusion : These findings in this study that the hydrotherapy was effective therapy in improving balance and gait velocity.

• Journal of Ocean Engineering and Technology
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• v.22 no.6
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• pp.95-99
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• 2008

The block assembly of ship consists of a certain type of heat processes such as cutting, bending welding residual stress relaxation and fairing. The residual deformation due to welding is inevitable at each assembly stage. The geometric inaccuracy caused by the welding deformation tends to preclude the introduction of automation and mechanization and needs the additional man-hours for the adjusting work at the following assembly stage. To overcome this problem, a distortion control method should be applied. For this purpose, it is necessary to develop an accurate prediction method which can explicitly account for the influence of various factors on the welding deformation. The validity of the prediction method must be also clarified through experiments. This paper proposes a simplified analysis method to predict the welding deformation of panel block structure. For this purpose, a simple prediction model for fillet welding deformations has been derived based on numerical and experimental results through the regression analysis. On the basis of these results, the simplified analysis method has been applied to some examples to show its validity.

• Journal of Technologic Dentistry
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• v.29 no.2
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• pp.65-77
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• 2007

This study is for the purpose of studying the validity of the construction of items and grading of the evaluation table at clinical practice used as the method of evaluation when clinical practice of Dept. of Dental Technology. 205 dental technicians in 4 cities were questioned to analyze the relation between items of the evaluation table at clinical practice and its grading. The collected materials were inspected by SAS V8 for Windows. The results are as follows: 1. Making up all the items and grading seem to be appropriate because they had the marks more than midium(more than 3.28). 2. Making up detailed items and grading seem to be trusted because they had the marks more than 3.30. 3.The significance level of the relation between items of the evaluation at clinical practice and its grading by t-inspection is p<0.0001 and so it appears to be meaningful. 4. It proved to be meaningful in result of regression analysis of the influence on the construction of the evaluation at clinical practice and its grading. With this result, further study is needed for the better methods of the evaluation in its adjustment and graduated grading among the items.

• Journal of Korean Institute of Fire Investigation
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• v.11 no.1
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• pp.41-58
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• 2008

The history of illumination has been much long since the discovery of lamplight caused huge changes in human lives. However, the swift development of the illumination actually started with the invention of a carbon filament lamp by Thomas Edison in 1878. Generally, the illumination tools plays important roles in human lives such as reduction of fatigue, improvement of safety and working efficiency, and the creation of enjoyable atmosphere. But, the illumination tools can be an origin of the fire due to carelessness and lack of management. In this study, the principle and structure of the illumination lamp were dealt with. The possibility of the fire outbreak caused by the incandescent lamp and fluorescent lamp most used in home was investigated. The examples of the fire outbreaks by the incandescent and fluorescent lamps and by the contact between the inflammable materials and the distributing wires were mentioned and demonstrated by the experimental.