• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 제5회 박판성형 SYMPOSIUM
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• pp.49-54
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• 2006

During most of manufacturing processes of auto-body panels, the trimming line should be designed in advance prior to flanging. It is an important task to find a feasible trimming line to obtain a precise final part shape after flanging. This paper proposes a new fast method to find feasible trimming line based on one-step analysis. The basic idea of the one-step analysis is to seek for the nodal positions in the initial blank from the final part, and then the distribution of strain, stress and thickness in the final configuration can be calculated by comparing the nodal position in the initial blank sheet with the one of the final part. The one-step analysis method is able to predict the trimming line before flanging since the desired product shape after flanging can be defined from the final configuration and most of strain paths are simple during the flanging process. Finally, designers can obtain a discrete trimming line from the boundary of the developed meshes after one-step analysis and import it into CAD system in the early design stage. The proposed method has been successfully applied to two basic curve flanging processes demonstrating many advantages.

• 산업공학
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• 제18권3호
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• pp.247-252
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• 2005

In the automated production environment in the present days, the minimization of manual operation becomes a very important factor in increasing the efficiency of the production system. The exit burr produced through the milling operation on the edge of workpiece usually requires manual deburring process to enhance the level of precision of the resulting product. So far, researchers have developed various methods to understand the formation of exit burr in cutting process. One method to analytically identify the formation of exit burr was to use the geometrical information of CAD and CAM data used in automated machining. This method, in turn, generated the information resulting from the analysis such as burr type, cutting region, and exit angle. Up to now, the geometrical data were restricted to the single feature and single path. In this paper, a method to deal with the complicated geometric features such as line segment, arc, hole, and spline will be presented and validated using the field data. This method also deals with the complex workpiece shape which is a combination of multiple features. As for the cutting path, multiple tool path is analyzed in order to simulate the real cutting process. All this analysis is combined into a Windows based software and real data are used to validate the program in the conclusion.

• 한국압력기기공학회 논문집
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• 제11권2호
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• pp.61-67
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• 2015

3D FEM modeling based on 3D CAD data has been performed to evaluate the efficiency of CP system in a real operating nuclear power plant. The results of it successfully produced sophisticated profiles of electrolytic potential and current distributions in the soil of an interested area. This technology is expected to be a breakthrough for detection technology of damages on buried pipes when it comes into combining with a brand of area potential earth current (APEC) and ground penetrated radar (GPR) technologies. 2D current distribution and 2D current vectors on the earth surface from the APEC survey will be used as boundary conditions with exact 3D geometry data resulting in visualization of locations and extents of corrosion damages on the buried pipes in nuclear power plants.

• 한국BIM학회 논문집
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• 제1권1호
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• pp.26-31
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• 2011

국내에서 BIM의 실무 활용은 건축공사 중심으로 적용되고 있다. 건축공사의 부위별 객체 특성이 정형적, 수직적, 반복적인 형태를 갖는 반면에 토목공사의 객체 특성은 비정형적, 수평적, 비반복적인 형태를 갖으므로 3D객체 구성이 어렵기 때문이다. 본 연구에서는 토목공사의 기획단계부터 설계단계까지의 업무 및 정보관리의 문제점을 파악한 후 BIM기반에서의 적용 프로세스를 제안하며, 제시한 프로세스를 기반으로 BIM시스템을 구축하여 교량공사를 대상으로 실무 적용성을 검토한다.

• 한국분무공학회지
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• 제23권2호
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• pp.58-65
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• 2018

An analytic strategy to control the variable valve actuation applied to two intake valves (flow port intake valve and swirl port intake valve) was performed in this study. we considered the variation in phasing of intake valve profiles by using the Cam-in-Cam technology. The analytic model was implemented in the GT-Power simulation program and analyzed the result of regulated emissions such as, NOx and Soot, especially with IMEP characteristics. Namely, we meticulously investigated the sources of having effect on the amount of NOx and soot formation under the test conditions with retard timing of both flow port and swirl port intake valves for decreasing the opening duration by 35CAD. Also, we analyzed the effect of incylinder pressure and temperature with NOx variations and in-cylinder pressure and temperature on NOx variations and normalized turbulent intensity. Through this analysis, some useful results on the combustion and flow characteristics of the swirl port and flow port control of the intake valve were obtained by this study.

• 복식문화연구
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• 제14권3호
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• pp.443-456
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• 2006

The purpose of this study is to present inner wear design making use of domestic characters that can represent the emotions of those kidults, to develop differentiated products as a result of recent revitalization of inner wear industry and to propose the possibility of total marketing in domestic character industry. Three characters of Barunson, which leads the way in developing domestic character products for inner wear design to satisfy the needs of the emotional generation were selected and work began on the designs based on the selected characters' images and themes. The result of this study was as follows. First, adding new designs using characters to inner wear fits the trend. Second, it was able to expand a range of characters' marketability by developing inner wear designs using domestic stationary and fancy characters as motives, and to seek the possibility of developing 'total marketing' plans in domestic character industry. Third, we were able to recognize the possibility of domestic character development and the importance of design development by developing products making use of domestic characters rather than foreign characters.

• 대한치과기공학회지
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• 제33권1호
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• pp.7-14
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• 2011

Purpose: As the demand and importance of aesthetic aspects in dental treatment become higher, much attention is paid to materials used for dental prostheses. Thus, the marginal fidelity of most-commonly used alloy, IPS - Empress and ZrO2 ceramic is compared. Methods: The alloy core made by casting, IPS - Empress core made by pressing and ZrO2 ceramic core made by CAD/CAM are used to make 10 samples respectively. For each core, three points were measures and the optical microscope (Axio Imager.Alm,Zeiss co., Oberkochen, Germany) was used to observe the cores with a magnification of 100. Results: As for alloy, IPS - Empress and ZrO2 ceramic, the average and deviation of their marginal distance are $29.91\;{\pm}11.93{\mu}m$ for alloy, $33.45\;{\pm}8.61{\mu}m$ for IPS - Empress, and $31.55\;{\pm}9.85{\mu}m$ for ZrO2. The one-way ANOVA test was conducted to compare them. However, there was no statistically significant difference among them. Conclusion: The study on marginal fidelity of alloy, IPS - Empress, and ZrO2 ceramic shows they have no marginal fidelity problem clinically. Therefore, if a system is selected based on the patient's condition or treatment method, there will be no problem.

• 한국의류산업학회지
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• 제8권3호
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• pp.303-309
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• 2006

This study intended to compare and analyze marking efficiencies of basic slacks, based on different cloth and production conditions, the width of cloth, the number of marking pieces and the direction for marking deployment and proposed an efficient marking method. The results were as follows. On the whole, the marking efficiencies increased with increasing cloth widths. In the case of small number of marking pieces, the efficiency increased with increasing cloth widths, while, for large number of marking pieces, there was no differences in the efficiency with the cloth widths. From the result of the comparison of the marking efficiencies with the number of marking pieces, it was shown that, in the case of small cloth width, the efficiency increased considerably with increasing number of marking pieces, while, in the case of large cloth width over two markers, there was no distinct effect of the number of markers on the marking efficiency. Thought there were some differences of the marking efficiencies with the marker directions, bi-direction marker was the most efficient marker, followed by one-direction for each size marker and one-direction marker.

• 한국디지털건축인테리어학회논문집
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• 제12권2호
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• pp.67-76
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• 2012

BIM and its quantity take-off widely apply to the construction projects and LCCO2 Assessment using the BIM's quantity take-off function can be tried recently. Because BIM modeling programs such as Revit and ArchiCAD do not provide adequate library for LCCO2 Assessment, quantity take-off data should be conversed and applied to Carbon Emission Coefficient using Excel program or manual work. Therefore, the purpose of this research is 1) to propose the Unit Conversion Systems for Carbon Emission Coefficient, 2) to provide basic library sets for BIM based LCCO2 Assessment method, and 3) to apply 11 material library sets on a apartment unit plan modeling to pursue the CO2 emission evaluation of the material production in the process of LCCO2 Assessment. Research results showed CO2 emission amount of 458.64kgCO2/m2 from the apartment unit plan modeling.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.224-230
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• 2005

In order to realize a three-dimensional shape on CAD, the machining process has been widely used because it offers practical advantages such as precision and versatility. However, the traditional machining process needs a large amount of time in cutting a product and the remained material causes trouble such as inconvenience due to cleaning process. This paper introduces a new rapid manufacturing process called Rapid Heat Ablation process (RHA) using the rotary hot tool to overcome limitations of traditional machining process. The rotary hot tool to satisfy requirements of RHA process is designed and produced. In order to examine relationships between kerfwidth and process parameters such as heat input, speed of tool and speed of revolution, experiments were carried out. In addition, relationship between the kerfwidth and the effective heat input was obtained. Based on the experimental results, double-curved shape was ablated to show the validity of proposed process. In the procedure, the rough cut and fine cut were performed according to the conditions of process parameters without tool change process. The practicality and effectiveness of the proposed process have been verified through ablation of three-dimensional shape.