• Transactions of Materials Processing
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• v.5 no.2
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• pp.97-104
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• 1996

It is very important to obtain the knowledge of loads and flow patterns in most processes because these information are the fundamental data of die design and process design. The objective of present study is to investigate loads and metal flow patterns for various process conditions in flat die extrusion of square-bars from circular billets. For analyzing the metal flow patterns of the billets photo etching is used on sections of split specimen. From this method metal flow patterns are analyzed for various area reductions friction factors and punch stroke through the process from initial-stage to final-stage. Experiments are carried out with hard solder billets at room temperature.

• 한국금형공학회:학술대회논문집
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• 2008.06a
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• pp.35-38
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• 2008

A pattern master and a Ni stamper for 50nm class of patterns are fabricated through e-beam lithography and Ni electroforming process. A model pattern set is designed, which is based on unit patterns of 50nm, 100nm, 150nm and 200nm in length and 50nm in width. The e-beam process is optimized to fabricate designed patterns with some parameters including dose, accelerating voltage, focal distance and developing time. For Ni electroforming to fabricate Ni stamper, a seed layer, a conducting layer, is deposited first on the pattern master fabricated by an e-beam lithography process. Ni, Ti/Ni and Cr are first tested to find optimal seed layer process. Currently the best result is obtained when adopting Cr deposited to be 100nm thick with continuous tilting motion of the master substrate during the deposition process.

• The Research Journal of the Costume Culture
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• v.18 no.4
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• pp.741-754
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• 2010

The current study aims to link Korean tradition to modern culture; to re-produce patterns of lotus depicted in Minwha, The study also aims to discover the beauty of Korean tradition and to modernize it. The current study is based upon document searches(including research papers) and the Internet searches. Through these searches, it investigates the concept of Minhwa, the origin of lotus depiction and its symbolic meanings, the traits of such pattern. Based upon this investigation, the study attempts to modernize the patterns of lotus and apply the modernized patterns to designing shirts. The process which employs the lotus patterns illustrated in Minhwa to shirt design includes four sub-processes: selecting, allocating, coloring, and selecting production techniques. The sub- process of selecting patterns is two folded: the first stage covers carbon-copying the distinctive features of lotus, lotus leaf, lotus bud, lotus pip, and lotus stem; the second stage is making these features suitable to shirt sizes. For the process of coloring those shirts, Piccaso's work(Pablo Picasso, 1881~1973) has been selected and the colors in his work have been adopted to dye the rest of the shirts as well as the lotus features. The process of selecting production techniques includes ornament tail in order to modernize the patterns allocated in the shirts. Once these processes are completed, the shirts are made on a scale of real-life size. These processes of creating shirt design by modernizing traditional patterns will hopefully contribute to researchers expanding the domain of shirt design.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.1
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• pp.63-68
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• 2015

Micro/nano patterns for optical concentration and diffusion have been studied in the various fields such as displays, optics, and sensors. Conventional micro patterns were continuous and linear shapes due to using linear-type light sources, however, recently non-continuous patterns have been applied as point sources are used for dot-type light sources such as LEDs and OLEDs. In this study, a hybrid machining technology combining an indentation machining method and an AAO process was developed for manufacturing the non-continuous micro patterns having nano patterns. First, mirror-like surfaces ($R_a<20nm$) of pure Aluminum substrates were obtained by optimizing cutting conditions. Then, The letter of 'K' consisting of the arrays of the micro patterns was manufactured by the indentation machining method which has a similar principle to indentation hardness testing. Finally, nano patterns were machined by AAO process on the micro patterns. Conclusively, a specific letter having nano-micro hybrid patterns was manufactured in this study.

• Journal of Intelligence and Information Systems
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• v.29 no.2
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• pp.285-301
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• 2023

Due to the increasing demand and importance of non-face-to-face education, open online learning platforms are getting interests both domestically and internationally. These platforms exhibit different characteristics from online courses by universities and other educational institutions. In particular, students engaged in these platforms can receive more learner autonomy, and the development of tools to assist learning is required. From the past, researchers have attempted to utilize process mining to understand realistic study behaviors and derive learning patterns. However, it has a deficiency to employ it to the open online learning platforms. Moreover, existing research has primarily focused on the process model perspective, including process model discovery, but lacks a method for the process pattern and instance perspectives. In this study, we propose a method to identify learning patterns within an open online learning platform using process mining techniques. To achieve this, we suggest three different viewpoints, e.g., model-level, variant-level, and instance-level, to comprehend the learning patterns, and various techniques are employed, such as process discovery, conformance checking, autoencoder-based clustering, and predictive approaches. To validate this method, we collected a learning log of machine learning-related courses on a domestic open education platform. The results unveiled a spaghetti-like process model that can be differentiated into a standard learning pattern and three abnormal patterns. Furthermore, as a result of deriving a pattern classification model, our model achieved a high accuracy of 0.86 when predicting the pattern of instances based on the initial 30% of the entire flow. This study contributes to systematically analyze learners' patterns using process mining.

• Journal of Information Technology and Architecture
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• v.10 no.3
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• pp.295-303
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• 2013

This paper presents a new approach to managing dynamic business process changes based on business process change patterns. We identify and categorize business process change patterns that occur recurrently in a dynamic business environment. Several issues regarding management of process versions are discussed, and a pattern-based version management method for handling process changes more flexibly is explained in detail. We propose a mechanism for abstract process execution with runtime encapsulation of a business process, which can maximize the flexibility of process execution using multiple process versions. In addition, we propose a concept of process promotion and demotion that can dynamically choose an actual version of the process at run-time. With our pattern-based process change management and versioning approach, it is expected that the flexibility and efficiency of BPM systems can be enhanced significantly.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.143-145
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• 1996

A new method of fabricating 3-dimensional patterns on single crystal silicon is presented in this paper. The method utlizes both chemical and mechanical reactions to make patterns with dimensions of few microns in width and submicron in height. The primaryadvantage ofthis new method over conventional methods of making patterns on silicon lies in its cost effectiveness and speed. The process introduced in this paper is a maskless process and does not reauire expensive capital investment. It is expected that this method can be employed for flexible and cost effective fabrication of micro-machine components in MEMS application.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.180-183
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• 2006

The recognition of emotionality becomes so important that it is called 'emotional consumption society'. The emotional design, which is mostly concerned about users consensus and experiences, is understood from a interactive point of view, human, and space. Today, the emotional design is a new paradigm. From this point of view, this paper, which presents patterns analysis of outdoor lighting by the emotional design, applies expression techniques of the emotional design in Analysis process of outdoor lighting patterns. Also, this paper shows examples at analysis process.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.11
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• pp.1256-1263
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• 2012

The present study covers the ultrasonic patterning process to replicate micro-patterns on a polymer substrate. The ultrasonic patterning process uses ultrasonic waves to generate frictional heat between an ultrasonic horn and the polymer substrate, from which the surface region of the polymer substrate is softened sufficiently for the replication of micro-patterns. The ultrasonic patterning process can divided into two categories according to the direction of vibration transmission: direct patterning and indirect patterning. The direct patterning uses a patterned horn, and the ultrasonic vibration is transferred directly from the patterned horn to the substrate. On the contrary, the indirect patterning process uses a plain horn, and the micro-patterns are engraved on a mold that is located below the substrate. Thus, the micro-patterns are replicated as an indirect manner. In this study, these direct and indirect patterning processes are compared in terms of the replication characteristics. Additionally, the possibility of double-side patterning is also discussed in comparison with the conventional single-side patterning process.

• The Research Journal of the Costume Culture
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• v.31 no.5
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• pp.607-626
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• 2023

This study analyzes consumer fashion purchase patterns from a big data perspective. Transaction data from 1 million transactions at two Korean fashion brands were collected. To analyze the data, R, Python, the SPADE algorithm, and network analysis were used. Various consumer purchase patterns, including overall purchase patterns, seasonal purchase patterns, and age-specific purchase patterns, were analyzed. Overall pattern analysis found that a continuous purchase pattern was formed around the brands' popular items such as t-shirts and blouses. Network analysis also showed that t-shirts and blouses were highly centralized items. This suggests that there are items that make consumers loyal to a brand rather than the cachet of the brand name itself. These results help us better understand the process of brand equity construction. Additionally, buying patterns varied by season, and more items were purchased in a single shopping trip during the spring season compared to other seasons. Consumer age also affected purchase patterns; findings showed an increase in purchasing the same item repeatedly as age increased. This likely reflects the difference in purchasing power according to age, and it suggests that the decision-making process for pur- chasing products simplifies as age increases. These findings offer insight for fashion companies' establishment of item-specific marketing strategies.