• Laser Solutions
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• v.18 no.3
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• pp.6-8
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• 2015

Finishing process includes deburring, polishing and edge radiusing. It improves the surface profile of specimen and eliminates the alien substance on surface. Deburring is the elimination process for debris of edges. Polishing lubricates surfaces by rubbing or chemical treatment. There are two types for electron finishing. The one is using pulse beam. The other is using the convergent and scanning electron beam. Pulse type device appropriates the large area process. But it does not control the beam dosage. Scanning type device has advantages for dosage control and edge deburring. We design the convergence and scan type. It has magnetic lenses for convergence and scan device for scanning beam. Magnetic lenses consist of convergent and objective lens. The lenses are designed by the specification(beam size and working distance). In this paper, we evaluate the convergence performance by pattern process. Also, we analysis the results and important factors for process. The important factors for process are beam size, pressure, stage speed and vacuum. These results will be utilized into systematizing pattern shape and the factors.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.4
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• pp.32-37
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• 2010

One of the most common engineering processes using plastics is the injection molding. In addition, plastics are utilized over the entire areas in our life including cars and home appliances among others for their characteristics with no deterioration even after a long time, as well as for their light weights in addition to their good durability. This paper aimed to minimize defects through prior analyses on the weld line, air traps, filling time, molding temperature and deformation patterns among others while carrying out interpretations on the cooling, filling and deformation in the injection process using the moldflow for rear lamp reflectors among components for a car in making parts through the coating process after injection.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.116-116
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• 2012

국내 섬유산업의 경쟁력을 향상시키고 채산성을 확보하기 위해 고부가가치 섬유 제품의 개발이 요구된다. 심미성을 발현하는 대표적인 후가공 기술인 카렌더 가공은 국내뿐만 아니라 국외 후진국에서도 보편화된 기술로 대량 생산으로 인한 가공비 저하, 물량 확보 등에 많은 어려움을 격고 있어 고부가가치의 신기술을 요구한다. 최근 이태리, 일본 등의 선진국에서 후가공 기술인 EMBO 롤러를 이용한 무아레 가공 원단이 고가로 거래되고 있다. 무아레(Moire)는 프랑스어로 "물결 모양의 무늬"라는 뜻으로 직물에 파형(波形)또는 나뭇결 무늬를 나타나게 하는 가공 기술로, 국내에서도 EMBO 롤러를 이용하여 무아레 가공을 하거나 두 겹의 원단을 이용한 무아레 가공이 시도되고 있으나, 전자의 경우 사용되는 롤러가 일반 롤러에 비해 훨씬 고가이고 한 종류의 롤러로 제한된 패턴 밖에 표현할 수 없고 적용 소재가 한정되는 등 많은 단점을 지니고 있고, 후자의 경우 세탁내구성이 나빠 상품화조차 되지 못하고 있어 현재 국내 섬유가공 기술로는 고내구성을 가지고 다양한 효과를 발현하는 무아레 가공이 불가능한 실정이다. 직물의 경 위사 밀도차이를 이용하여 무아레를 형성할 수 있다는 점에 착안하여, 경 위사 조직을 갖는 이형(離型)원단에 PU 수지를 코팅하여 격자무늬(grid) 필름을 제조하고 제조된 Grid 필름과 Base원단을 라미네이팅하여 경 위사 밀도차에 의해 무아레 무늬를 형성할 수 있었다. 이형원단과 Base원단의 경 위사의 밀도에 따라 다양한 패턴의 3차원 무아레 무늬를 발현시킬 수 있으며 합성섬유 및 천염섬유 등의 원단 소재에 제약 없이 영구 내구성의 무아레 제품을 생산할 수 있을 것으로 판단된다. 본 연구에서는 Grid 필름을 이용한 무아레 가공을 위하여 이형원단 제조 조건을 확립하였고, grid 필름 캐스팅 조건, 라미네이팅 조건을 달리하여 이형성 및 무아레 형상을 비교하여 고찰함으로써 제품화에 필요한 요소 기술의 기초를 마련하고자 한다.

• Korean Journal of Optics and Photonics
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• v.21 no.2
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• pp.53-60
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• 2010

An integrated light guide plate (LGP) was designed for liquid crystal displays (LCD) without using prism and diffuser sheets. The integrated LGP is textured with micro-patterns on both the top and bottom surfaces. The textures effectively substitute for a single prism-sheet and a diffuser sheet in LCD displays without decreasing the brightness and uniformity. A LCD display with our integrated light guide is simulated to give average luminance of 4560 cd/$m^2$, luminance uniformity of 83% horizontal viewing angle $60^{\circ}$ and vertical viewing angle $56^{\circ}$. Therefore an ultra thin (slim) back light unit can be constructed with fewer optical sheets, which reduces the manufacturing cost and so improves price competitiveness.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.6
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• pp.7-13
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• 2015

The production processes were reviewed through the injection analysis of the shift lever as a core component of an auto lever installed in the automatic transmission of cars. The injection analysis was carried out for the shift lever and rod among the components in a shift lever module. The shift lever and rod are designed for injection molding with the insertion of a tube, a pin cable plate, and a steel rod for securing the strength of the product. The charging time, failure of injection molding, weld line, air trap, and deformation were reviewed according to this insert. Analyses on various gate positions were carried out for reviewing the cultivation and deformation of fiber around major components, such as the generation section of manipulation feeling and assembly section, so that optimal gate conditions might be reviewed and reflected in the mold design. Finally, we plan to compare the analysis results with the production of trial products.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10c
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• pp.363-365
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• 1998

텍스트 마이닝(Text Mining)이란 텍스트형태의 문서들의 패턴 또는 관계를 추출하여 사용자가 원하는 새로운 정보를 가공하거나 기존의 정보를 변형하는 과정을 말한다. 텍스트 마이닝의 기능에는 문서 범주화(Document Categorization), 문서 군집화(Document Clustering), 그리고 문서 요약(Document Summarization)이 이에 해당된다. 문서 범주화란 문서에게 사전에 정의한 범주를 부여하는 과정을 말하고, 문서 군집화란 문서들을 계층적 구조로 형성하는 과정을 말하고, 문서 요약이란 문서의 전체 내용을 대표할 수 있는 내용의 일부만을 추출하는 과정을 말한다. 이 논문에서는 문서 범주화만을 다룰 것이며 그 대상으로는 신문기사로 설정하였다. 그의 범주는 4가지로 정치, 경제, 스포츠, 그리고 정보통신으로 설정하였다. 문서 범주화는 문서 분류(Document Classification)라고도 하며 문서에 범주를 자동으로 부여하여 기존에 인위적으로 부여함으로써 소요되는 시간과 비용을 절감하는 것이 목적이다. 문서 범주화에 대하여 k-NN(k-Nearest Neighbor)와 신경망을 이용하였으며, 신경망을 이용한 경우가 k-NN을 이용한 경우보다 성능이 우수하였다.

• The Journal of Bigdata
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• v.8 no.1
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• pp.131-156
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• 2023

The traditional retail industry significantly changed over the past decade due to the mobile and online technologies. This change has been accompanied by a shift in consumer behavior regarding purchasing patterns. Despite the rise of online shopping, there are still specific categories of products, such as "Processed food" in Mongolia, for which traditional shopping remains the preferred purchase method. To prepare for the inevitable future of retail businesses, firms need to closely analyze the performance of their offline stores to plan their further actions in a new multi-channel environment. Retailers must integrate diverse channels into their operations to stay relevant and adjust to the shifting market. In this research, we have analyzed the performance data such as sales, profit, and amount of sales of offline stores by using clustering approach. From the clustering, we have found the several distinct insights by comparing the circumstances and performance of retail stores. For the certain retail stores, we have proposed three different strategies: a fulfillment hub store between online and offline channels, an experience store to elongate customers' time on the premises, and a merge between two non-related channels that could complement each other to increase traffic based on the store characteristics. With the proposed strategies, it may enhance the user experience and profit at the same time.

• Journal of the Korea Convergence Society
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• v.12 no.1
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• pp.89-97
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• 2021

Recently, as the importance of forced indoor living has increased in the untact era, the connection and relationship between space environments is increasing. That is, the smart interaction environment for providing services in various spaces collects and processes a number of surrounding environment information through various sensors to provide desired information according to the required place and time. In this environment, a new type of interaction paradigm is needed for the user to select and focus on environmental information. In this paper, we provide guidelines based on models and patterns for designing various interactions around space. Through interaction model-based technology, we provide guidelines for space-oriented interaction design. We propose an ideal interaction environment through guideline-based patterns and templates. Finally, by providing a space-oriented interaction environment suitable for smart interaction, users can freely obtain desired information.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.13 no.3
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• pp.10-24
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• 2014

Bicycle is a useful transportation mode that is healthy, emission-free, and environmentally compatible. Although large efforts have been made to promote the use of bicycling to date, there still exist various hurdles and limitations. One of the key issues to increase bicycling is how to gather bicycle-related data from the field and to generate valuable information for both users and operations agencies. This study proposes a method to process bicycle trajectory data which is obtained from tracing global positioning systems(GPS) equipped bicycle, which is defined as the probe bicycle. The proposed method is based on the concept of statistical quality control of data. In addition, a data collection and processing scenario in support of public bicycle system is presented. The outcomes of this study would be valuable fundamentals for developing bicycle traffic information systems that is a part of future intelligent transportation systems(ITS).

• Journal of Nutrition and Health
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• v.57 no.1
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• pp.153-169
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• 2024

Purpose: The main goal of this study was to identify the impact of coronavirus disease 2019 (COVID-19) on grocery purchases (i.e., fresh and processed foods by grain, vegetable, fruit, seafood, and meat categories) in Korea. To understand the specific impact of COVID-19, the study period was divided into 3 segments: PRE-COVID-19, INTER-COVID-19, and POST-COVID-19. Methods: We used the microdata of household income and expenditure from Statistics Korea (KOSTAT), representing households across the country. The data comprised monthly grocery expenditure data from January 2019 to September 2022. First, we compared the PRE-COVID-19 period to INTER-COVID-19 and then INTER-COVID-19 to POST-COVID-19 and used multiple regression analysis. The covariates used were the gender and age of the head of the household, the household's monthly income, the number of family members, the price index, and the month (dummy variable). Results: The expenditures on all grocery categories except fresh fruit increased from PRE-COVID-19 to INTER-COVID-19. From INTER-COVID-19 to POST-COVID-19, almost all grocery category spending declined, with processed meat being the only exception. Most purchases of protein sources, increased during INTER-COVID-19 compared to PRE-COVID-19, while ham/sausage/bacon for meat protein, fish cakes and canned seafood for seafood protein, and soy milk for plant-based protein did not decrease during POST-COVID-19 compared to INTER-COVID-19. Conclusion: These results show an overall increase in in-home grocery expenditure during COVID-19 due to an increase in eating at home, followed by a decrease in this expenditure in the POST-COVID-19 period. Among the trends, the protein and highly processed convenience food categories did not see a decline in spending during the POST-COVID-19 period, which is a reflection of the preferences of consumers in the post-COVID-19 period.