• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.2
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• pp.118-123
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• 2016

Overlap cutting is a fundamental method of applying abrasive water jet (AWJ) machining to milling to produce a wider surface because the nozzle outlet is approximately 1.0 mm wide. In this study, the effects of overlap cutting on the depth profile and surface roughness are investigated. The overlapping area depends on the amount of step over, which is controlled in the pick-feed direction. If the step over is equal to or larger than the diameter of the nozzle, no overlap cut occurs but large cusps remain between the cut paths. A step over as small as one-thirds of the nozzle diameter may lead to triple-overlap cutting resulting in an extraordinary depth. By using pocket milling experiments with a step over of 0.46 (or 0.47), it is verified that AWJ can produce a milled surface of titanium, one of the hard-to-cut materials, with $76{\mu}m$ Ra.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.2
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• pp.126-131
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• 2004

On-machine automatic measuring software from 3-D solid modeler is generally applied to assess the functional performance of a final produce for computer numerical control (CNC) machine. Automatic measuring software may also be performed on individual components of CNC machine in which some functional aspect of the component must be examined and cannot be implicity determined by means of a mechanical inspection. The manufacturing specialist, combined with the appropriate software simulation, can not only create the commands to drive the virtual measuring but also can check for mistakes by viewing the computer graphics simulation of the tool cutting sequence.

• International Journal of CAD/CAM
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• v.3 no.1_2
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• pp.1-12
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• 2003

When milling concave corners, cutter load increases momentarily and fluctuates severely due to concentration and uneven distribution of material stock. This abrupt change of cutter load produces undesirable machining results such as wavy machined surface and cutter breakage. An important factor for studying cutter load in 2.5D pocket milling is the instantaneous Radial Depth of Cut (RDC). However, previous work on RDC under different corner-cutting conditions is lacking. In this different corner shapes. In our work, we express RDC mathematically in terms of the instantaneous cutter engage angle which is defined as Cutter Swept Angle (CSA). An analytical approach for modeling CSA is explained. Finally, examples are shown to demonstrate that the proposed CSA modeling method can give an accurate prediction of cutter load pattern at cornering cut.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10b
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• pp.901-908
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• 1988

In machining die cavities or mechanical parts, we often encounter the needs to remove a material within a given boundary. Even though this pocket cutting capability has been implemented in many NC packages, most of them can handle convex shaped pockets bounded by curves of limited types and numbers. In this work, a procedure has been developed to machine pockets of a free surface bounded by lines, circular arcs and free curves. Also, the cutter location data is computed directly without using iterative method for better computational efficiency.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.43-48
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• 2001

In this study, the characteristics of the surface around a hole on inlet and outlet of product which are manufactured by face mill or end mill cutting with a hole or a pocket in its surface, are investigated. Furthermore, experiment for optimization of process conditions to minimize the change of characteristics of milling cut surface after a hole cutting operation, is implemented. Applying the results in this study to surface manufacturing of mold products whose surface is uneven or metal products made by diecasting, reducing the number of sequence process to obtain fine surface is expected.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.5
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• pp.1-6
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• 2002

This study is to investigate the characteristics of the surface around a hole on inlet and outlet of product which are manufactured by face mill or end mill cutting with a hole or a pocket in its surface. Furthermore, experiments for optimization of process conditions to minimize the change of characteristics of milling cut surface after a hole cutting operation are implemented. This result is apply to manufacture of mold products and metal products by diecasting.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.9
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• pp.58-63
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• 2019

In this research, we examine the change of dimensional accuracy in the cutting process while changing cutting conditions such as feed rate and spindle rotational speed with chromium molybdenum steel (SCM415) material and TiCN- and TiAlN-coated end mill tools. According to dimensional accuracy measurement, TiCN-coated tool displays the most accurate dimensional tolerance at ${\varnothing}20mm$ at feed rates of 200 mm/min and 250 mm/min at a spindle rotation speed of 4,000 rpm. The largest dimension of the coating tool was able to make the TiAlN-coated tool suitable when comparing the smallest dimension.

• Journal of the Korean Society of Costume
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• v.56 no.7 s.107
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• pp.68-84
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• 2006

The aim of this study is to examine a structure of trousers worn by males in the western world during the 17th and 18th centuries in order to understand the characteristics of evolution in construction. it mainly examined engravings from these era because they provided me fine and detailed portrayals of what it needed to observe. Then, it classified them into models according to each era. it supplemented a flaw of depending on single type of studying material by examining other types of historical materials such as historical paintings and documents for comparative analysis of materials and decorations and previous studies on preserved historical documents to observe the examples of structures of trousers. Secondly, it studied both historical documents and previous studies on the trousers patterns used back in those days, analyzed the characteristics of each designing method by actually draping these patterns, and observed the differences in these completed patterns to understand the characteristics of changes in fashion design skill. As for the changes in length, these patterns show only a slight difference around above and below the knee line. However, the widths of waist, hip, girth and hem were significantly altered over the years to reduce wrinkles and the cutting lines became more refined to make the clothes fit to the body. As a result, a simple but fine patterning technique was born. In particular, new methods in cutting and sewing were invented for detailed parts such as waist, pocket, front and slit.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1994.04a
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• pp.691-700
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• 1994

Voronoi diagram of a set of geometric entities on a plane such as points, line segments, or arcs is a collection of Voronoi polygons associated with each entity, where Voronoi polygon of an entity is a locus of point which is closer to the associated entity than any other entity. Voronoi diagram is one of the most fundamental geometrical construct and well-known for its theoretical elegance and the wealth of applications. Various geometric problems can be solved with the aid of Voronoi diagram. For example, the maximum tool diameter of a milling cutter for rough cutting in a pocket can be easily found, and the pocketing tool path can be efficiently generated from Voronoi diagram. In PCB design, the design rule checking can be easily done via Voronoi diagram, too. This paper discusses an algorithm to construct Voronoi diagram of a simple polygon which consists of simple curves such as line segments as well as arcs in a plane with O(nlogn) time complexity by employing the divide and conquer scheme.

• Journal of the Korea Fashion and Costume Design Association
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• v.16 no.4
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• pp.99-116
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• 2014

The purpose of this study was to examine the state of scrub wearing among scrub uniforms medical staff. The results of the research is the following. First, As for the state of scrub uniforms, they wore scrubs only while they gave medical treatment and took care of routine work. Regarding the design of their current scrubs, type 1 was dominant, and the most common color was dark sky blue. Second, Concerning considerations for scrub design, they answered that scrubs should be designed to give no inconvenience during job performance. As for the image, they placed the most importance in a clean image due to hygiene. In relation to preference for color, pattern and materials, they had the most preference for dark blue, no pattern and materials that would not easily be contaminated. Third, As to preference for the length of the top, they were most fond of hip length, and short sleeves were their favorite length of sleeve. Concerning the design of the front and the back of the top, they had a liking for a box style with no straight cutting line. As for the design of the neckline, hem and pocket of the top, they had the most preference for round neckline, square bottom and round patch pocket respectively. Fourth, when the design preference of the respondents was analyzed, there were a difference between the men and the women in preference for neckline design. The women had a liking for round neck, whereas the men were fond of V neck. And the women showed a higher preference for rubber waistband than the men for the waist design of the pants. No gender differences were found in preference for color, pattern and the length of the top.