• Design & Manufacturing
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• v.11 no.3
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• pp.29-34
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• 2017

Increased demand for parts with micro-pattern structure made of metals, ceramics, and composites in various fields such as medical ultrasonic sensors, CT collimators, and ultra-small actuator parts. Micro powder injection molding (PIM) is a technology for manufacturing micro size, high volume, complex, precision, net-shape components from either metal or ceramic powder. In the present study, a standard mold with a variable insert core capable of producing various micro patterns was investigated. An injection molding test was performed on a standard mold using a line type micro-pattern core having an aspect ratio of 2, a slenderness ratio of 70, a pattern size of $200{\mu}m$, and a pattern spacing of $150{\mu}m$. During the filling process, the deformation of the mold with large aspect ratio and slenderness ratio was analyzed by the experiment and the numerical simulation according to the position of the gate. We proposed a mold structure that minimizes mold deformation by gate modification and enables uniform pattern filling behavior.

• Fashion & Textile Research Journal
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• v.24 no.5
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• pp.545-556
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• 2022

To overcome the pandemic, a new strategy for innovation is in demand throughout the value chains of the fashion industry that emphasize the importance of fashion technology. Accordingly, as various viewpoints and fields of debate are unfolding to consider the direction of change led by fashion technology, it is necessary to make an active value judgment precedent by understanding the differences between various opinions. This study aims to derive keywords from fashion technology used during the pandemic, to infer the characteristics of each type of perspective and to understand their characteristics. For the research, this study combines text mining analysis and content analysis. Text mining analysis is used to find statistical patterns by collecting keywords from big data from online media, and content analysis is used to interpret the data qualitatively. After analyzing the results of this study, the following observations are made. First, the perspective of positive acceptance seeks to maximize the perception and sensory action of fashion through technology; this amplifies experience, an opportunity for innovation and efficiency. Second, critical vigilance highlights the side effects of radical changes in fashion technology, characterized by concerns about capital-centered polarization, threats to human rights, and infringement of creative thinking. Lastly, the perspective of gradual adoption is the gradual convergence of technologies, characterized by the pursuit of an appropriate balance.

• Journal of Intelligence and Information Systems
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• v.22 no.4
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• pp.45-67
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• 2016

Given the recent development of smart devices, users are producing, sharing, and acquiring a variety of information via the Internet and social network services (SNSs). Because users tend to use multiple media simultaneously according to their goals and preferences, domestic SNS users use around 2.09 media concurrently on average. Since the information provided by such media is usually textually represented, recent studies have been actively conducting textual analysis in order to understand users more deeply. Earlier studies using textual analysis focused on analyzing a document's contents without substantive consideration of the diverse characteristics of the source medium. However, current studies argue that analytical and interpretive approaches should be applied differently according to the characteristics of a document's source. Documents can be classified into the following types: informative documents for delivering information, expressive documents for expressing emotions and aesthetics, operational documents for inducing the recipient's behavior, and audiovisual media documents for supplementing the above three functions through images and music. Further, documents can be classified according to their contents, which comprise facts, concepts, procedures, principles, rules, stories, opinions, and descriptions. Documents have unique characteristics according to the source media by which they are distributed. In terms of newspapers, only highly trained people tend to write articles for public dissemination. In contrast, with SNSs, various types of users can freely write any message and such messages are distributed in an unpredictable way. Again, in the case of newspapers, each article exists independently and does not tend to have any relation to other articles. However, messages (original tweets) on Twitter, for example, are highly organized and regularly duplicated and repeated through replies and retweets. There have been many studies focusing on the different characteristics between newspapers and SNSs. However, it is difficult to find a study that focuses on the difference between the two media from the perspective of supply and demand. We can regard the articles of newspapers as a kind of information supply, whereas messages on various SNSs represent a demand for information. By investigating traditional newspapers and SNSs from the perspective of supply and demand of information, we can explore and explain the information dilemma more clearly. For example, there may be superfluous issues that are heavily reported in newspaper articles despite the fact that users seldom have much interest in these issues. Such overproduced information is not only a waste of media resources but also makes it difficult to find valuable, in-demand information. Further, some issues that are covered by only a few newspapers may be of high interest to SNS users. To alleviate the deleterious effects of information asymmetries, it is necessary to analyze the supply and demand of each information source and, accordingly, provide information flexibly. Such an approach would allow the value of information to be explored and approximated on the basis of the supply-demand balance. Conceptually, this is very similar to the price of goods or services being determined by the supply-demand relationship. Adopting this concept, media companies could focus on the production of highly in-demand issues that are in short supply. In this study, we selected Internet news sites and Twitter as representative media for investigating information supply and demand, respectively. We present the notion of News Value Index (NVI), which evaluates the value of news information in terms of the magnitude of Twitter messages associated with it. In addition, we visualize the change of information value over time using the NVI. We conducted an analysis using 387,014 news articles and 31,674,795 Twitter messages. The analysis results revealed interesting patterns: most issues show lower NVI than average of the whole issue, whereas a few issues show steadily higher NVI than the average.

• 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 Veterinary Clinics
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• v.18 no.4
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• pp.380-389
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• 2001

Non-human primates have been increasing in demand as important experimental animals and companion animals, domestically and internationally. The number of non-human primates for these purposes will be much enhanced in the near future. Despite this trend, basic physiological data are scarcely available in these animal species, leading to the difficulty to diagnose diseases when necessary, due to the absence of reference values. Particularly, there is not any report on the total activity of LDH of non-human primates, let alone LDH isoenzyme patterns, in Korea. LDH isoenzymes have a high level of efficaciousness as diagnostic and prognostic aids in various diseases. In this study, total activities and isoenzyme patterns of LDH were measured to obtain their reference values in domestically reared common marmosets, crab-eating macaques and Japanese macaques. There were widespread different values of serum total LDH among the non-human primate species experimented in this study. Serum LDH values of common marmosets and crab-eating macaques were 597.5$\pm$243.1 IU/l and 605.3$\pm$312.6 IU/l, respectively, whereas those of Japanese macaque showed 1,209$\pm$473.8 IU/l. Five isoenzyme fractions of LDH were observed in all experimented non-human primates but their ranks and proportions represented different patterns one another. In common marmosets, the percent of fraction for serum LDH1, LDH$_2$, LDH$_3$, LDH$_4$, and LDH$_{5}$ was 13.7$\pm$6.4%, 23.3$\pm$3.6%, 29.2$\pm$5.0%, 9.4$\pm$1.4% and 24.4$\pm$7.5%, respectively. The rank of LDH isoenzymes was LDH$_3$>LDH$_{5}$>LDH$_2$>LDH$_1$>LDH$_4$, in the descending order. For crab-eating macaques, the fraction of serum LDH$_1$, LDH$_2$, LDH$_3$, LDH$_4$, and LDH$_{5}$ occupied 19.5$\pm$12.7%, 25.3$\pm$9.3%, 23.8$\pm$8.1%, 10.2$\pm$2.8% and 21.3$\pm$14.2%, respectively. The order of LDH isoenzymes was LDH$_2$>LDH$_3$>LDH$_{5}$>LDH$_1$>LDH$_4$, from top to down. On the while, in Japanese macaques, the fraction of serum LDH$_1$ to LDH$_{5}$ showed 23.4$\pm$11.8%, 30.5$\pm$4.1%, 17.4$\pm$3.9%, 11.3$\pm$3.7% and 13.8$\pm$5.6%, respectively. The decreasing order indicated LDH$_2$>LDH$_1$>LDH$_3$>LDH$_{5}$>LDH$_4$. In conclusion, values such as LDH and LDH isoenzyme patterns of investigated for the first time from non-human primates reaared in Korea, could be reference values for the optimal diagnosis and therapy of diseases of the corresponding animal species. Other parameters of hematology and blood biochemistry are urgently needed to study for the benefit of our intimate non-human primates.an primates.

• Journal of Fashion Business
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• v.6 no.2
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• pp.41-52
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• 2002

At the beginning of the modern times, orientalism and ethnic character was the main stream of current fashion. Early in the twentieth century, orientalism had a tremendous affect on various areas of society, culture, and art. Particularly, it inspired and activated the design of costume. A great variety of colors and construction of the Orient and geometrical simplicity were based on the creation of modern costume. Ethnic placed weight on the Orient because Japan strengthened competitiveness and China opened the door to foreign countries. Therefore, a large number of the oriental costume produced by a variety of fashion designers. The oriental handicraft, motif and colors of the traditional costume have been used in modern costume. In addition, they are precious ideas for designers. This thesis is about a Study on costume embroidery close to fashion through the oriental embroidery and the concept of oriental embroidery. It is also a study on patterns, skills and colors of the oriental embroidery shown in modern fashion and practical use through the designers works. First, concept, process of change, patterns, skills and colors of the oriental embroidery are mainly discussed. 1.The oriental embroidery consists of life, Buddhism, appreciation and costume embroidery. Embroidery was widely used for a variety of purposes. First, it is to make a good impression and beauty. Second, to decorate many kinds of patterns and shapes. Last, to indicate social status and stages. 2.The origin of the oriental embroidery started in Persia. was It greatly developed in Iran and was introduced in Korea via China. We are reminded of the oriental embroidery of China. China is the original place of oriental embroidery. Oriental embroidery has developed the peculiar embroidery according to each climate, custom and nationality. On the basis of these, the practical use of the oriental embroidery on modern fashion is presented through patterns, skills and colors which leads Korean designers use. Even though the oriental embroidery is not very popular among people owing to a great deal of cost and a demand for labor, the patterns and colors of the embroidery has been already familiar with the contemporaries A more profound study on the oriental embroidery will supply a great deal of material and ideas to the fashion industry. Moreover, an effort to raise self-pride in traditional culture will be also in need.

• Information Systems Review
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• v.12 no.1
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• pp.189-207
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• 2010

We applied IT ecosystem analysis to Smart Grid system in this paper and thereby compared various arguments about Smart Grid technologies against the reality of the power generation and distribution in South Korea with a special attention to the power distribution side. Our work attempts to propose policy implications in the government-level based on a firm-level analysis using the framework of the competitive strategy and advantage. The Smart Grid initiative is expected to enhance the efficiency in the power generation and distribution. In addition, the Smart Grid initiative aims at capturing the opportunities in the electric power business such as parts, components, supplies, and system products in the global arena. Prerequisites of smart distribution system include building infrastructure based on smart distribution parts, information systems, communication technologies, and developing various application programs and interfaces that would interact with the consumers. Consumers are expected to play an integral role by changing their consumption patterns in response to dynamic pricing and quality choices enabled by the smart distribution technologies. In order to induce the consumers to participate actively in the program, firms and policy makers should consider providing consumers economic incentives and proper education for better understanding of new technologies. Our work helps policy makers and firm better understand the nature of technology and stakeholders for the successful implementation of smart distribution technologies.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.6
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• pp.1398-1417
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• 2013

A method is proposed to reduce excess resources from a virtual machine(VM) while avoiding subsequent migrations for a computer cluster that provides cloud service. The proposed scheme cuts down on the resources of a VM based on the probability that migration may occur after a reduction. First, it finds a VM that can be scaled down by analyzing the history of the resource usage. Then, the migration probability is calculated as a function of the VM resource usage trend and the trend error. Finally, the amount of resources needed to eliminate from an underutilized VM is determined such that the migration probability after the resource reduction is less than or equal to an acceptable migration probability. The acceptable migration probability, to be set by the cloud service provider, is a criterion to assign a weight to the resource reduction either to prevent VM migrations or to enhance VM utilization. The results of simulation show that the proposed scheme lowers migration frequency by 31.6~60.8% depending on the consistency of resource demand while losing VM utilization by 9.1~21.5% compared to other known approaches, such as the static and the prediction-based methods. It is also verified that the proposed scheme extends the elapsed time before the first occurrence of migration after resource reduction 1.1~2.3-fold. In addition, changes in migration frequency and VM utilization are analyzed with varying acceptable migration probabilities and the consistency of resource demand patterns. It is expected that the analysis results can help service providers choose a right value of the acceptable migration probability under various environments having different migration costs and operational costs.

• Journal of the Korean Society of Systems Engineering
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• v.18 no.1
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• pp.1-13
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• 2022

The Yongin Light Rail train was manufactured by Bombardier Transportation in Canada in 2008 and is a privately invested railway line that has been operating in Yongin-si, Gyeonggi-do, since 2013. When the frequency of train failure increases due to aging, and there is a delay in the delivery period of imported parts used in the Bombardier manufactured trains, timely vehicle maintenance may not be performed due to lack of parts. To solve this problem, it is necessary to build a 'vehicle parts maintenance demand forecasting system' that analyzes the accurate and actual maintenance demand annual based on the condition of vehicle parts. The full scope of analysis in this paper analyzes failure data from various angles after opening of Yongin light rail vehicle to analyze failure patterns for each part and identify replacement cycles according to possible failures and consumption of parts. Based on this study, it is expected that Yongin Light Rail's maintenance system will change from the existing time-based replacement (TBM) concept to the condition-based maintenance (CBM) concept. It is expected that this study will improve the efficiency of the Yongin Light Rail maintenance system and increase vehicle availability. This paper is a fundamental for establishing of a system for predicting the replacement timing of vehicle parts for Yongin Light Rail. It reports the results of data analysis on some vehicle parts.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.1
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• pp.1-14
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• 2020

Various policies and studies regarding use of PBSS (Public Bike Sharing System) and Programs (PBSP) have been conducted worldwide as the number systems or programs has increased. Although various phenomena and demands have been generated by the use of PBSS in everyday life, the majority of research and the policies in South Korea have been implemented focused on commuting life. The purpose of this study aimed to understand various PBSS demands using PBSS usage data in 2018 in the Yeouido districts through classifying usage patterns and analyzing features. The rental stations were classified into three types based on weekday/weekend usage rates. The usage of Yeouido's PBSS accounted for 4.3% of the total usage in Seoul Metropolitan City, while the number of PBSS rental stations accounted for 2% of all rental stations in the Seoul urban areas. Rental stations with a higher weekday utilization rates showed high utilization rates in all four seasons and were mainly distributed in work and residential areas. Other stations showed a concentrated usage pattern in spring (April-May) and autumn (September-October) seasons, and their locations were close to the entrance of nearby parks. Besides, renting and returning were often concentrated at certain rental stations for high weekend utilization as compared to the pattern of high weekday usage. Therefore, PBSS management and programs should be operated to reflect various usage demands rather than uniform PBSS operations. The result of this study is meaningful to provide basic data for effective PBSS operation by monitoring the demand for PBSS usage in spatio-temporal terms.