• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.2
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• pp.185-189
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• 2010

This study considered the feasibility of controlling the air concentration by oscillating flow in fuel cell channels. The fuel cell stack performance is largely influenced by the air concentration. If the air concentration is lower than 2.5 times the stoichiometric of the inlet air, the fuel cell stack performance seriously deteriorates because of air starvation. In this respect, optimizing the air concentration is crucially important to maximizing the fuel cell stack performance. In this work, the effects of oscillating actuation were studied to control the concentration. Studies have shown that there are two non-dimensional key parameters related to the frequency and oscillating amplitude. This paper presents how those parameters affect the performance of the stack.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.6
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• pp.25-31
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• 2004

In this paper, we introduce kinetic Monte Carlo (kMC) methods for simulating diffusion process in nano-scale device fabrication. At first, we review kMC theory and backgrounds and give a simple point defect diffusion process modeling in thermal annealing after ion (electron) implantation into Si crystalline substrate to help understand kinetic Monte Carlo methods. kMC is a kind of Monte Carlo but can simulate time evolution of diffusion process through Poisson probabilistic process. In kMC diffusion process, instead of. solving differential reaction-diffusion equations via conventional finite difference or element methods, it is based on a series of chemical reaction (between atoms and/or defects) or diffusion events according to event rates of all possible events. Every event has its own event rate and time evolution of semiconductor diffusion process is directly simulated. Those event rates can be derived either directly from molecular dynamics (MD) or first-principles (ab-initio) calculations, or from experimental data.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.8
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• pp.889-897
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• 2011

In this work, we investigated the theoretical forming limit models for Zircaloy-4 and Zirlo used for spacer grid of nuclear fuel rods. Tensile and anisotropy tests were performed to obtain stress-strain curves and anisotropic coefficients. The experimental forming limit diagrams (FLD) for two materials were obtained by dome stretching tests following NUMISHEET 96. Theoretical FLD depends on FL models and yield criteria. To obtain the right hand side (RHS) of FLD, we applied the FL models (Swift's diffuse necking, M-K theory, S-R vertex theory) to Zircaloy-4 and Zirlo sheets. Hill's local necking theory was adopted for the left hand side (LHS) of FLD. To consider the anisotropy of sheets, the yield criteria of Hill and Hosford were applied. Comparing the predicted curves with the experimental data, we found that the RHS of FLD for Zircaloy-4 can be described by the Swift model (with the Hill's criterion), while the LHS of the FLD can be explained by Hill model. The FLD for Zirlo can be explained by the S-R model and the Hosford's criterion (a = 8).

• Journal of Distribution Research
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• v.7 no.1
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• pp.61-86
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• 2002

The number of people who perform their banking business on Internet has been increasing drastically during the recent period and the trend still continues. Banks and other types of financial institutions are now competing intensely with each other in attracting customers to this new innovative banking service. The marketers in charge of formulating and implementing the strategies for this new banking business need to understand the behavioral factors as well as the technical factors in order to succeed in attracting more customers to this new service. products. A deep understanding as to why and how the customers are adopting the new service developed on information technology is a prerequisite for a successful marketing effort. The purpose of this dissertation is to find out what factors are playing important roles in the customers'decision related to the adoption of the Internet banking services. The focus of the research is threefold. First. by testing the hypotheses proposed by the Technology Adoption Model, a well-known theory in the IT-related behavioral science, an analysis was made as to which factors are more important in affecting the attitudes and adoption of the Internet banking on the part of customers. Secondly, an analysis was made as to whether the three criteria of the Technographics- -the attitude toward new technology, level of income, and the motivational factor- -are useful as the criteria for segmenting the Korean users of the online banking. Thirdly, an analysis was made as to whether each customer group segmented by the criteria of the Technographics reveal a differential decision process and thus requires a differential approach strategywise.

• Design Convergence Study
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• v.15 no.2
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• pp.37-52
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• 2016

The purpose of this study is to suggest functional priority to increase probability to be adopted by single-person household by designating single-person household as potential early adopter of smart home service. Smart home service is spread slowly for its value. This study applied diffusion of innovations theory to solve this problem. Single-person household who has no other family member who can take care of household is chosen as potential early adopter. This study tried to find grounds of functional priorities through an online survey. The survey questionnaires were composed as following. First, representative attributes of single- person household were reviewed, then measuring questions according to the attributes were recomposed based upon preceding study. After that, concept and status of smart home service were reviewed. and smart home service functions to be measured in this study were selected through analysis based upon representative cases, then Measuring questionnaire were made were three factors which chosen by referring to preceding study about perceived attributes of innovations applied to selected functions. As a result of analyzed 62 responses, except excluded functions which has perceived any special value, set priorites with 9 functions. These functional priorities obtained from these studies will play a role as fundamental data to provide valuable service to single-person household and have a meaning as a starting point to increase rate of adoption for smart home service.

• Information Systems Review
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• v.19 no.4
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• pp.135-156
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• 2017

An intelligent personal assistant (IPA) is a software agent that assists people to perform basic tasks or services for an individual by commonly providing information via natural language. In spite of the versatile capabilities of the IPA to answer a user's simple information-based queries, such as the weather and driving directions, the actual usage rates for IPA services are limited to date. In this research, to evaluate the factors affecting the intention to use IPA, we develop an empirical model based on technology acceptance model, innovation diffusion theory, and IS success model. Afterward, we collect 203 questionnaires from actual users of IPAs. Finally, the structural equation model validates the causal relationship between the constructs of the model. Consequently, the innovation characteristics of IPA drawn from innovation diffusion theory, namely, relative advantage, compatibility, observability, all exerted a positive influence on perceived usefulness. Furthermore, information quality, a quality characteristic of IPA obtained from DeLone and McLean's IS success model, presented a positive effect on perceived usefulness and perceived ease of use. Finally, the perceived intelligence of IPA displayed a positive influence on perceived usefulness and ease of use. This characteristic was also a major factor that can increase the intention to use the IPA. Given these research findings, this study is significant for identifying factors that may influence the intention to use the IPA by providing strategic guidelines to relevant business operators and establishing an integrated model.

• The Journal of the Korea Contents Association
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• v.15 no.4
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• pp.246-262
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• 2015

The digital divide has become an important social issue in the two waves of informatization and aging society. This study is to comprehensively examine various theoretical approaches and discussions on the mechanisms of the digital divide and to synthetically understand the features of the digital divide in old age. This study examines 1) four theoretical approaches on the mechanisms of digital divide among people in general, 2) three theoretical perspectives and six specific explanations on the digital divide in old age, and 3) five controversial features and concepts of the digital divide in old age. Consequently, this study suggests the need for a comprehensive approach to the multi-dimensional digital divide in old age and more attention to the digital divide in old age in terms of individual well-being and social inequalities. Further implications and limitations are discussed.

• Journal of Service Research and Studies
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• v.7 no.3
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• pp.37-55
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• 2017

Recently, many business organizations have been increasingly expanding the utilization of the intelligent chatbot services for effective customer relation management. The purpose of this study is to empirically investigate the factors which affect the use of the intelligent chatbot services. Above all, the research model and the hypotheses were derived through reviewing the major relevant theories such as UX(user experience) theory(Honeycomb model), TRA(theory of reasoned action), TAM(technology acceptance model) and ETAM(extended TAM). And then, structural equation analyses using SmartPLS 3.0 for 233 valid questionnaires replies collected through the field survey was performed to test the hypotheses. Theoretically, this study can contribute to providing the conceptual framework with regard to enhancing the use of intelligent chatbot services. And practically, this study sheds new light on suggesting the guidelines to designing the UX(user experience) of the intelligent chatbot services.

• International Commerce and Information Review
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• v.1 no.2
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• pp.325-344
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• 1999

연구방법론의 관점에서 통상정보학은 매우 다양한 방법으로 접근이 가능하며, 특히 정보통신기술을 적극적으로 활용할 수 있기 때문에 향상 새로운 접근 방법이 출현할 수 있다. 또한, 정보기술의 급격한 발전으로 국제전자상거래가 급격히 확산되고 있는 현 시점에서 수출기업의 단순한 무역자동화 수준을 벗어난 국제간 B to B 전자상거래의 전략적 활용방안에 대한 연구가 필요한 때이다. 이에 본 연구에서는 통상정보학의 실용성 제고를 위한 구체적인 연구방향으로써 전략 정보시스템과 조직이론을 가미한 조직간 정보시스템 이론을 제시함으로써, 조직간의 전략적 연계를 통한 전략적 통합정보시스템 구축전략을 제시하고자 하였다. 이를 통하여 정보화의 이점을 통상학 분야에 도입하고, 전략적으로 활용 가치가 있는 정보를 생산, 저장, 유통 및 활용함으로써 학술적 비용발생을 최소화하며, 기업의 이윤 발생을 촉진함으로써 국가경쟁력의 확보에 기여할 수 있도록 하는 것이 통상정보학의 궁극적인 지향 목표이다.

• The Journal of Art Theory & Practice
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• no.6
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• pp.123-145
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• 2008

Artist-in-residence which gets chances to create by artists' moving and encountering new culture is heightening its level in 21th century. Under the circumstance that issue of cultural diversity and the role of artists which is for city revitalization and sustainability are affect residency program in the midst of highly proceeded globalization that international exchange. Therefore, in the aspect of creative city, a new model is creating by reuse of abandoned industrial facilities and Asia or Eastern country become the subject in residency program management, the issue of cultural diversity is getting more important, programs based on project not just residence are managing. Furthermore, it has inter-country cooperating system in the rage of cultural management. It means that artists' space of creating activity has a new, social role in spontaneously we need to approach to following model in Korea, as well.