• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.4
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• pp.59-64
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• 2006

High Speed Machining(HSM) reduces machining time and improves surface accuracy because of the high cutting speed and feedrate. Development of HSM makes it allowable to machine difficult-to-cut material and use small-size-endmill. It is however limited to cutting condition and tool material. In the machining operation, it is important to check main parameter of tool life and select optimal cutting condition because tool breakage can interrupt progression of operation. In this study, cutting parameters are determined to 3 factors and 3 levels which are a spindle speed, a feedrate and a width of cut. Experiment is designed to orthogonal array table for L9 with 3 outer array using Taguchi method. Also, it is proposed to inspect significance of the optimal factors and levels by ANOVA using average of SN ratio for tool life. Finally, estimated value of SN ratio in the optimal cutting condition is compared with measured one in the floor shop and reduction of loss is predicted.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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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.

• The Journal of Sustainable Design and Educational Environment Research
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• v.21 no.3
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• pp.26-37
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• 2022

This study was conducted to develop a tool to investigate and analyze the educational effect of the school space innovation project, which is being promoted on a large scale at the national level. In order to analyze the educational effect of school space innovation, it is first necessary to analyze the structure of the space altered by the school space innovation. Research and analysis should be possible, so a user survey tool was developed for this purpose. It is expected that the survey tool in this study can be used for pre-investigation in the pre-planning stage of the school space innovation project and as a post-evaluation tool for investigating and analyzing the educational effects of space innovation.

• Journal of Korea Foundry Society
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• v.42 no.3
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• pp.191-197
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• 2022

This study aims to improve the machinability of gray cast irons in high speed cutting by using nonmetallic inclusions. In this research, small quantities of AL and Mg were added to conventional gray cast irons without influencing their mechanical characteristics and castability to investigate the effects of these nonmetallic inclusions in the gray cast irons on tool wear in high speed cutting. During the high speed turning of gray cast iron containing Al and Mg using a cermet tool, protective layers consisting of Al, Mg, Si, Mn, S and O were detected on the flank face and rake face of the tool, and flank and crater wear were significantly reduced compared to the turning of conventional gray cast iron and gray cast iron added with Al. The effect of inclusions on tool wear increased with increasing cutting speed, and flank and crater wear was the smallest at the cutting speed of 700m/min. Moreover, in face milling, the addition of Al and Mg drastically decreased the wear rate, and wear hardly progressed even in prolonged cutting length after initial wear. The amount of adhesion on tool faces increased as the cutting speed increased. This increase in cutting speed resulted in the formation of a thick protective layer and the reduction of tool wear. Furthermore, the addition of small amounts of Al and Mg prevented thermal cracks in the face milling of gray cast irons.

• The Research Journal of the Costume Culture
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• v.30 no.1
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• pp.161-171
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• 2022

Traditional tie-dyeing is widely implemented in the clothing handicraft culture in China, South Korea, and Japan. Since it was developed 2,000 years ago, it has become a popular method of fabric making in the world and is highly respected by fashion designers. Based on the existing traditional tie-dyeing methods, this study conducted specific research on the 3D printing technology of the SLS laser method and the micro tool design application method of the clamp-dyeing process. Through the experimental methods of this study, it proposes to use the "7000 Nylon" material, which is commonly used in 3D printing, to develop a new clamp-dyeing tool. This new tool can be widely used in the clamp-dyeing of fabrics, such as cotton, hemp, silk, and some chemical fibers. The applied method and principle can be consistent with the traditional clamp-dyeing method. Therefore, the innovation of tie-dyeing technology is the best protection measure for the development and inheritance of traditional fabric making. The continuation of artistic life needs originality, which is also the best response to market competition. At the same time, this new design of the clamp-dyeing tool has the characteristics of novelty, innovation, and rich changes, which aligns with the new fashion demands of current fabric design.

• The Journal of Economics, Marketing and Management
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• v.12 no.1
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• pp.53-64
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• 2024

Purpose: The purpose of this study is to develop a satisfaction evaluation survey tool that reflects the characteristics of the program for housing welfare supported in long-term public rental housing in Seoul. Research design, data and methodology: The main research methods of the study were review of previous studies, literature review, and expert consultation. Results: First, the characteristics of each housing welfare program being promoted by Seoul City were summarized, and the characteristics were reflected in the evaluation survey tool. Second, the SERVOUAL model, a service quality model, was used to measure satisfaction with the housing welfare program and modified to suit the characteristics of the program. Third, an evaluation survey tool was constructed by dividing the evaluation tool into common questions and individual questions, and for the operation and sustainability of the housing welfare program, rather than just evaluating satisfaction, program loyalty was used as a survey item. Fourth, through expert advice, more than 10 evaluation questions for each housing welfare program were revised. Conclusions: The results of future research are expected to be used to prepare practical operation plans through annual monitoring of housing welfare programs and comparative analysis between programs.

• Journal of Digital Convergence
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• v.10 no.3
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• pp.99-104
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• 2012

The digital forensics are new kinds of security that investigate and verificate fact relation about activities based on digital data. In this paper, we implemented digital forensic tool that can be used in collecting, analyzing, and reporting evidences. This tool support intuitional GUI that everybody can analyze easily. And a simple operation can collect and analyze active data. Also, we can decrease much time and endeavor by using this forensic tool that support reliable data.

• Korean Journal of Computational Design and Engineering
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• v.9 no.4
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• pp.334-350
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• 2004

Until now, architects have used traditional methods in order to develop architectural forms and use a digital technology as presentation tools. The field of digital technology has been expanded to control easily architectural data, eventually leads to the creation for creative ideas, which were belong to mainly designer's talent. It has been educated by using digital tool in foreign universities but in our case a little university try to do. So we need an adequate curriculum and educational media because of digitalized data, originated architectural form and reduction of time and money. In this paper, as it is surveyed the present situation of architetural education by using digital tool in domestic and foreign country, it can be used as the fundamental data that architectural education by using digital tool is initiated In our universities.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.48-52
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• 2002

The fault analysis of the CNC machine tool which is controlled sequentially by PLC is generally based on ladder diagram. When machine tool has faults, it takes a lot of operator's experiences and times to identify logical relationship because ladder diagram is a step structured language. Therefore the technologies of finding out fault reasons automatically is necessary. In this paper, the SFG(Switching Function Generator) system is developed to analysis fault reasons correctly. The SF(Switching Function) and SSF(Step Switching Function) generated from SFG based on ladder diagram are experimented to identify the performance of SFG.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.4
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• pp.129-134
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• 2000

This paper presents the development of ultra-precision machining process of large aspheric aluminum mirrors with a maximum diameter of 620 mm. An ultra-precision machine, "Nanoturn60", developed by Daewoo Heavy Industries Ltd. is used for machining and motion errors of the machine are compensated by using the FTS developed by IAE(Institue for Advanced Engineering) during the machining process. To check the form accuracy of machined aspheric surfaces, on-machine form measurement system is developed. This measurement system consists of air bearing touch probe, straight edge, and laser sensor. With in-process error compensation by FTS(Fast Tool Servo), aspheric mirrors with the from accuracy of submicron order are obtained. obtained.