• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 추계학술대회 논문집
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• pp.437-438
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• 2007

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.247-248
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• 2007

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1424-1428
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• 2004

A new design for deburring tools for intersecting holes is introduced. The tool tip is mounted on a slender cantilever assembled into a circular shank. The tool tip has been design to cover ranges of exit angle and diameter ratio between intersecting holes. The design is an improvement over the previous ones by the authors. Experiments have been performed on AL6061. With the new design, mild exit burrs with exit angles greater than 45$^{\circ}$ are successfully removed. For large burrs with smaller exit angles, however, the deburring could be incomplete.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 추계학술대회 논문집
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• pp.399-400
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• 2006

• 한국기계가공학회지
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• 제15권4호
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• pp.109-117
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• 2016

For efficient deburring of burrs that form inside mechanical parts after drilling, new special deburring tool was developed specifically for the burr found at intersecting holes. In this paper, the process for finding ideal cutting conditions has been carried out to identify the efficient performance of deburring using a new tool. The burrs at the entrance and exit surface were analyzed for efficient removal. The surface roughness after deburring was also reviewed for better performance. In addition, the influence of the feed rate on deburring quality was analyzed for improved productivity. Through this process, a new deburring tool can be applied effectively to remove burrs formed at intersecting holes.

• 한국정밀공학회지
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• 제23권9호
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• pp.47-53
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• 2006

An Experiment was carried out to find the scheme far minimization of burr formation on inclined exit surface in drilling. Several drills with different geometry are used for drilling the workpiece with inclined exit surface. Step drills are specified with step angle and step size. The influence of the inclination angle of exit surface on burr formation was observed, which enables to analyze the burr formation mechanism on inclined exit surface. Along the edge on the inclined exit surface, burrs are formed by the bending deflection to feed direction and also burrs are formed in exit direction of cutting edge. To minimize the burr formed in feed direction, the corner angle which is formed by the inclination angle and step angle must be large enough not to be bent to burr. By decreasing step angle of drill and decreasing the distance between two axes of two holes, burr formation at the intersecting holes can be minimized. Burr formation mechanisms are analyzed according to the drill geometries and cutting conditions. Several schemes far burr minimization on inclined exit surface were proposed.

• 한국의상디자인학회지
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• 제26권3호
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• pp.163-177
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• 2024

Korea has preserved a highly sophisticated silk fabric culture throughout its history. Among these fabrics, Ra (羅) was considered to be a premium gauze fabric that required advanced skill and dedication to utilize. Ra is a complex gauze fabric in which four warp threads are twisted together and intersect with the weft to form intricate holes. This unique structure gives Ra its distinctive transparency and elasticity among silk textiles. It was widely used for veils, garments, and various items from the Three Kingdoms period to the Joseon Dynasty. However, its complex weaving process limited production efficiency, leading to its decline. Today, Ra has become obsolete. This study focuses on the elastic characteristics of Ra, where intersecting warp threads create net-like structured holes. This stucturre was emulated by developing a silk knit using a Raschel knitting machine. The developed product consists of three types: one replicating the alternating complex structure present in the traditional patterns of Munra (紋羅), another reproducing the distinctive hexagonal holes of the 4-end complex gauze, and the last expressing the hexagonal holes with the weft passing through them. Inspired by Ra's traditional uses in clothing and everyday items, various products were designed and produced. These include a women's coat with Akjureum, a 17th-century Joseon-style women's Jeogori, a modern market-style Jeogori, and a envelope inspired by a Goryeo Dynasty pouch artifact. These items confirm the potential and applicability of the developed silk knit as a material for modern Hanbok products. This study underscores the significance of developing new textiles that incorporate traditional materials, highlighting how tradition can be preserved in diverse ways.

• Structural Engineering and Mechanics
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• 제90권2호
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• pp.143-157
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• 2024

Cold-formed steel (CFS) I sections are increasingly being used as load-bearing components in building constructions, and such I sections frequently incorporate web holes to facilitate service installation. The economical and structural advantages of these elements have prompted many researchers to investigate the behavior of such structures. Despite numerous studies on the buckling stability of castellated beams, there is a notable absence of experimental investigation into oval castellated beams with stiffeners. This study examines the local buckling of cold-formed steel castellated I-beams stiffened with oval constellations through experimental and numerical analysis. Four specimens are fabricated with and without stiffeners, including parallel, perpendicular, and intersecting types attached to the web portion of the beam, along with cross stiffeners for the oval-shaped openings at the beam ends. Additionally, a numerical model is developed to predict the behavior of castellated beams with oval openings up to failure, considering both material and geometric nonlinearities. Codal analysis is performed using the North American specification for cold-formed steel AISI S-100 and the Australian/New Zealand design code AS/NZS 4600. The anticipated outcomes from numerical analysis, experimental research, and codal analysis are compared and presented. It will be more helpful to the preliminary designers.