• Journal of Korean Association for Spatial Structures
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• v.1 no.1 s.1
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• pp.157-166
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• 2001

In general, the cutting pattern of the membrane structures is determined by dividing the complicated curved 3-D surface into several 2-D plane strip by using flattening technique. In this procedure, however, some discrepancies ore occurred between actual stresses of equilibrated state and designed uniform stresses because the material properties are not considered. These deviations can cause the critical structural problems, wrinkling or overstress, and thus a optimization process should be considered. In this paper, a new analytical method for determining an optimum cutting pattern considering material properties is presented. Here, iterative procedure is introduced to decrease the errors caused in numerical process. The optimization method proposed can diminish the deviations occurred by material properties and numerical errors, simultaneously. As a results, it is shown that the final stress distributions for the HP shell model are sufficiently near to design stress distributions, and it can be concluded that this method can be used to obtain the optimized cutting pattern of membrane structures.

• The Research Journal of the Costume Culture
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• v.31 no.1
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• pp.18-33
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• 2023

Zero-waste pattern cutting is a groundbreaking sustainable fashion practice. However, few brands and designers have pursued this method because it requires creative pattern design that diverges from the existing process of using pattern slopers. Therefore, application within the fashion industry is not sufficient. Therefore, in an attempt to highlight the key characteristics of zero-waste pattern design, this study classifies and analyzes cases in which similar designs employ zero-waste pattern-cutting techniques. We hope to make zero-waste pattern design more accessible by presenting realistic pattern-cutting guidelines. To this end, theoretical research on relevant literature, previous research, and online resources and an empirical analysis of cases involving zero-waste pattern cutting were conducted in parallel. As a result of the study, we were able to classify the factors of zero-waste pattern design in terms of fabric use, design, and composition. Regarding materials, our research revealed the importance of appropriate fabric width, understanding the difference between waste minimization and minimal fabric use, and easy reuse and recycling. In terms of design, the simultaneous progress of pattern and design work, adjustable loose silhouettes, and the use of surplus fabric for functional and decorative details emerged as key characteristics. For composition, we found that size adjustment limits, arrangement irregularity, and pattern shapes were crucial elements and that various arrangements revealed unlimited design potential.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.5
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• pp.969-983
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• 2020

Zero waste fashion design to minimize the 15% fabric waste generated during production can be difficult to industrialize instead of having strong originality. This study designed shirts that are practical and reflect trends using the zero waste pattern cutting method and suggest the possibilities for industrial production. The content of the study are as follows. First, the pattern cutting method of zero waste fashion design was studied. Second, the recent trends of shirt design were analyzed and reflected in the design development. Third, 4 zero waste shirt designs were developed and produced by applying the geometric cutting, puzzle cutting, and minimal cutting methods. As for the research method, literature research was conducted on related references; in addition, design development and production were conducted empirically. As a result, the developed zero waste shirts are practical and trendy. In addition, the results of the study are meaningful to provide basic data for the commercialization and industrial application of zero waste fashion design.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.11a
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• pp.725-726
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• 2008

• Journal of the Korean Society for Precision Engineering
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• v.13 no.12
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• pp.30-37
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• 1996

On-line process control equipment for CO$_{2}$ laser cutting is not available for industrial applications. The major part of the industrial laser cutting machines are adjusted off-line by highly educated engineers. The quality inspection of the sample is visual and referred to different quality scales. Due to the lack of automation the potential laser users hesitate to implement the cutting method. The first step toward an automation of the process is the development of a process monitoring system and the research is cincentrated on the area of on-line quality monitoring during CO$_{2}$ laser cutting. The method is based on the detection of the emitted light from the cutting front by photo diode. The developed monitoring system consists of the OP Amplifier, A/D convertor, power supply and PC. The signal from the photo diode has been undertaken from Fourier analysis and statistical analysis with real time. The photograph of striation pattern was taken by metallurgical microscope. As a result, it is possible to predict the striation pattern according to the beam traveling speed.

• Journal of Powder Materials
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• v.22 no.3
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• pp.169-174
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• 2015

The optical film for light luminance improvement of BLU that is used in LCD/LED and retro-reflective film is used as luminous sign consist of square and triangular pyramid structure pattern based on V-shape micro prism pattern. In this study, we analyzed machining characteristics of Cu-plated flat mold by shaping with diamond tool. First, cutting conditions were optimizing as V-groove machining for the experiment of micro prism structure mold machining with prism pattern shape, cutting force and roughness. Second, the micro prism structure such as square and triangular pyramid pattern were machined by cross machining method with optimizing cutting conditions. Burr and chip shape were discussed with material properties and machining method.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.04a
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• pp.175-182
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• 1998

The object of this study is shape finding and cutting pattern generation of membrane structures under the following assumptions : (1) material is linearly elastic (2) stress state is plane stress. Cable and membrane structures should introduce the nonlinear analysis considering geometric nonlinearity because these structures deform largely under the external loads. The analysis procedure is consisted of three steps considering geometric nonlinearity unlike any other structures. First step is the shape finding analysis to determine the initial equilibrium shape. Second step is the stress-deformation analysis to investigate the behaviors of structures under various external loads. Once a satisfactory shape has been found, a cutting pattern based on the shape finding analysis may be generated from the view point of construction. In this paper, (1) shape finding analysis formulation and an example, (2) cutting pattern determination procedure using weighted least-square minimization flattening method and some results are presented.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.266-273
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• 1998

The object of this study is shape finding and cutting pattern generation of membrane structures under the following assumptions: (1) material is linearly elastic (2) stress state is plane stress. Cable and membrane structures should introduce the nonlinear analysis considering geometric nonlinearity because these structures deform largely under the external loads. The analysis procedure is consisted of three steps considering geometric nonlinearity unlike any other structures. First step is the shape finding analysis to determine the initial equilibrium shape. Second step is the stress-deformation analysis to investigate the behaviors of structures under various external loads. Once a satisfactory shape has been found, a cutting pattern based on the shape finding analysis may be generated from the view point of construction. In this paper, after shape finding analysis, cutting pattern determination procedure using weighted least-square minimization flattening method and some results are presented.

• Geomechanics and Engineering
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• v.20 no.5
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• pp.421-432
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• 2020

Cutting of rocks is very common encountered in tunneling and mining during underground excavations. A deep understanding of rock-tool interaction can promote industrial applications significantly. In this paper, a distinct element method based approach, PFC^3D, is adopted to simulate the rock cutting under different operation conditions (cutting velocity, depth of cut and rake angle) and with various tool geometries (tip angle, tip wear and tip shape). Simulation results showed that the cutting force and accumulated number of cracks increase with increasing cutting velocity, cut depth, tip angle and pick abrasion. The number of cracks and cutting force decrease with increasing negative rake angle and increase with increasing positive rake angle. The numerical approach can offer a better insight into the rock-tool interaction during the rock cutting process. The proposed numerical method can be used to assess the rock cuttability, to estimate the cutting performance, and to design the cutter head.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.629-630
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• 2008