• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.1
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• pp.7-12
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• 2006

Recently, the fractal interpolation methods have been widely introduced and used to estimate and analyze various theoretical and experimental data. Because of the chaotic behaviors of dynamic cutting force data, some method for end-milling force analysis must be used. The fractal analysis used in this paper is fractal linear interpolation and fractal dimension. Also, several methods for computing fractal dimensions have been used in which the fractal dimension of the typical dynamic end-milling force was calculated according to number of data points that are generally lower than 200 data points sampled. This fractal analysis shows a possible prediction of end-milling force that has some dynamic chatter property or stationary property in endmilling operation.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.5
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• pp.142-147
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• 2012

Machining tool conditions directly affect to quality of product and productivity of manufacturing. Many researches performed for tool condition monitoring in machining process to improve quality and productivity. Conventional methods use characteristics of signal for cutting force, motor current consumption, vibration of machine tools and machining sound. Recently, diameter of machining tool is become smaller for minimizing of mechanical parts. Tool condition monitoring using conventional methods are relatively difficult because micro machining using small diameter tool has low machining load and high cutting speed. These days, the direct monitoring for tool conditions using vision system is performed actively. But, vision system is affected by external conditions such as back ground of image and illumination. In this study, minimizing technology of external conditions using distribution analysis of image data are developed in micro machining using small diameter drill and tap. The image data is gathered from vision system. Several sets of experiment results are performed to verify the characteristics of the proposed machining technology.

• Journal of Korean Society for Quality Management
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• v.31 no.3
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• pp.172-184
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• 2003

Many companies in Korea are paying close attention to Six Sigma to get better business results. And there are numerous success stories on the use of statistical methods in solving problems, improving processes and cutting costs. However, there are many cases in which statistical methods are misused or inappropriately applied. In this paper, the pitfalls to avoid in using statistical methods are discussed. Also the role of statistics in Six Sigma is examined.

• Journal of Korean Association for Spatial Structures
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• v.12 no.1
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• pp.109-119
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• 2012

For membrane structure, there are three main steps in design and construction, which are form finding, statistical load analysis, and cutting patterning. Unlike the first two stages, the step of cutting pattern involves the translation of a double-curved surface in 3D space into a 2D plane with minimal error. For economic reasons, the seam lines of generated cutting patterns rely greatly on the geodesic line. Generally, as searching regions of the seam line are plane elements in the step of shape analysis, the seam line is not a smooth curve, but an irregularly divided straight line. So, it is how we make an irregularly divided straight line a smooth curve that defines the quality of the pattern. Accordingly, in this paper, we analyzed interpolation schemes using spline, and apply these methods to cutting pattern generation on the curved surface. To generate the pattern, three types of spline functions were used, i.e., cubic spline function, B-spline, and least-square spline approximation, and simple model and the catenary-shaped membrane was adopted to examine the result of generation. The result of comparing the approximation curves by the number of elements and the number of extracted nodes of simple model revealed that the seam line for less number of extracted nodes with large number of elements were more efficient, and the least-square spline approximation provided smoother seam line than other methods.

• Journal of the Korean Society of Costume
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• v.66 no.7
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• pp.124-138
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• 2016

The present study observes collaboration methods in which 3D printing was a part of the fashion manufacturing process, expression methods of such cases, and their ripple effects. As a result, the three types of collaborations between fashion designers and other industry fields, fashion brands and 3D printing companies, and fashion designers and artists. Case analysis results and ripple effects found according to each collaboration method were as follows. First, in collaborations found were between fashion designers and other industry fields, 3D printed fashion works with futuristic images were seen through the fusion of future industries, which claim to support cutting edge digital technology, and creative fashion design. As they were mainly collaborations between automobile industries with cutting edge images or digital related industries and fashion designers, they were expressed as a new form of experimental clothing, and were used as strategies to improve future corporate images of the high tech industry. Second, in collaborations between fashion brands and 3D printing technology businesses, the sporting good brands and the shoe industry attempted to let their products be known through the promotion of functional material or ergonomic technology. While they emphasize practicality by mainly using flexible material, they were mainly proposed as functional sporting goods for famous players or as shoe accessories, so methods are still used for public distribution as brand promoting marketing strategies. Third, with collaborations between fashion designers and artists, creative pieces were shown through the grafting of 3D printing technology, the artistry of artists, and the experimentation of fashion designers. In particular, the innovative value of fashion as art was created through the union of the artistic 3D modeling technology support of artists and the creativity of designers. Like this, 3D printing fashion can graft the cutting edge nature of fashion to other industry fields through collaborations, enhancing pacesetting images, and in the fashion field, it can improve possibilities for innovations in the fashion industry through the support of 3D printing technology businesses and artists, raising expectations towards future human living.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.6
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• pp.220-228
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• 2010

A steel wire-integrated deck plate that welds integrated triangle truss steel wires on a galvanized steel sheet is developed to reduce construction costs of a slab or formwork such as shores and supports, and it is already widely applied in many construction fields. This study selected upper and lower steel wires, lattice steel wires, span, and cutting methods of ends as variables, and conducted an experimental test by manufacturing a total of 32 full scale test bodies. According to the result, changes in final destruction types of the test bodies and cutting methods of ends didn't affect structural performance of test bodies, and for a 3.2m-span test body, there was no big problems in using ${\Phi}4.5$ of lattice steel wires.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.1
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• pp.89-98
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• 2012

A steel wire-integrated deck plate that welds integrated triangle truss steel wires on a galvanized steel sheet is developed to reduce construction costs of slabs or formworks such as shores and supports, and it is already widely applied in many construction fields. In this research, experimental tests for 14 full scale specimens, which are in the same field conditions, are conducted on several parameters such as the diameter of top, bottom and lattice steel wire, cutting methods of ends. According to the result, changes in final destruction types of the test bodies and cutting methods of ends didn't affect structural performance of test specimens, and for a 4.0m-span test specimen, there was no big problems in using bottom bar D7 or D8.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.26 no.1
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• pp.35-40
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• 2016

End milling process is one of the broadly used manufacturing process for precision machined parts and products. Machining performance is often limited by chatter vibration at the tool-workpiece interface. Chatter vibration is a type of machining self-excited vibration which originated from the variation in cutting forces and the flexibility of the machine tool structure. Even though lots of cutting tooling methods are developed and used in machining process, precise analysis of cutting tooling effect in view of chatter vibration behavior. This study presents numerical and experimental approaches to verify and effects of various cutting parameters to affect to chatter vibration stability. Acquired knowledge from this study will apply the optimal cutting conditions to improve a machining process.

• The Korean Journal of Community Living Science
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• v.17 no.1
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• pp.101-108
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• 2006

This study was conducted to develop the regulating methods for the optimal harvest stage of new sprout for woody plants, and to clarify the effects of storage condition and period on the growth of new sprout formed of Aralia elata cv. 'Jeongkwang'. Japanese angelica tree were collected in the Jangheung district of Jeonnam on 20. March, 2005, and those cut branches were stored at $5{\pm}2^{\circ}C$ and 80 to 90% of the relative humidity, and were cut in water. Survival rate of cut branches for Aralia elata cv. 'Jeongkwang' was significantly increased when that was used for the cutting after the collection with no storage. And those survival rate was much more increased when that was stored at 80 to 90% of relative humidity than 40 to 50% of relative humidity. Number of new sprouts formed which were not stored immediately after the collection 3.2 to 3.4, and that were stored at cold storage room before cutting and cut on 1. June and 1. August were 5.1 to 5.3. Leaf growth of cut branches cut in water on 20. March started at ten days after cutting, and that on 1. June and 1. August at one to two days after cutting. Slow and mature sprout growth of Aralia elata cv. 'Jeongkwang' which were cut in water were different by the cold storage periods. Nineteen days were needed for the mature growth of sprout when cut in water on 20. March, and thirteen days on 1. August.

• Archives of Plastic Surgery
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• v.47 no.3
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• pp.250-255
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• 2020

Background Rosenthal et al. classified female, habitual, non-suicidal wrist cutters as a group and introduced the concept of wrist-cutting syndrome. We investigated the characteristics of wrist-cutting patients at our institution in comparison with results reported previously. Methods We conducted a retrospective study involving 115 patients who had cut their wrists and been examined at the emergency department of a single hospital in Seoul, Korea, between March 2014 and August 2018. Results There were more women (73 patients; 63.5%) than men (42 patients; 36.5%), and the women (mean age, 34.42 years) were significantly younger than the men (mean age, 50.07 years). The patients who had cut their wrists repeatedly were mainly women (22 of 26 patients; 84.6%); however, men caused more severe damage than women. Substance use before a suicide attempt did not significantly increase the severity of wrist cutting. Our institution planned and implemented a suicide prevention intervention program to improve the continuity of outpatient care. The number of patients who continued psychiatric treatment increased significantly after program completion. Conclusions We confirmed that most patients were young women who were not suicidal in the true sense because their wounds were not severe. Our study showed a protective role of the barrier tendons (flexor carpi radialis, palmaris longus, flexor carpi ulnaris), and we suggest careful repair of the barrier tendons to protect neurovascular structures against subsequent cutting events. We found that it was possible to improve the continuity of patient counseling by managing patients through a psychiatric treatment program.