• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6B
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• pp.641-649
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• 2006

The behavior of a three-dimensional pure rectangular water jet with aspect ratio of 10 was experimentally investigated based on the results of the mean velocity field obtained by PIV. The saddle back distribution was observed in the lateral distribution along the major axis. The theoretical centerline velocity equation derived from the point source concept using the spreading rate for the axisymmetric jet was in good agreement with the measured centerline velocity and gave the division of the potential core region, two-dimensional region, and axisymmetric region. The range of the two-dimensional region divided by the criterion of the theoretical centerline velocity decay for the aspect ratio of 10 was observed to be smaller than that of the transition region. The applicability of the two-dimensional model to the behavior of the rectangular jet with low aspect ratio or the wastewater discharged from a multiport diffuser in the deep water of real ocean may result in significant error in the transition and axisymmetric regions after the two-dimensional region. In the two-dimensional region, the Gaussian constant tended to be conserved, and the spreading rate slightly decreased at the end of the two-dimensional region. The normalized turbulent intensity along the centerline of the jet initially abruptly increased and showed relatively higher intensity for higher Reynolds number.

• Journal of Service Research and Studies
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• v.13 no.4
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• pp.47-69
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• 2023

The main purpose of this study is to examine the mediating effects of performance satisfaction and audience loyalty through the motivation and community satisfaction of non-profit performance attendees in the local community. Motivations were examined by distinguishing between intrinsic and extrinsic factors to understand the profound desires of the audience. A survey was conducted targeting attendees who had experienced non-profit performances in the Jeju area over the past year to gather data. Ultimately, the survey responses from 363 participants were used as the basis for analysis. The results of the analysis indicated that higher levels of intrinsic and extrinsic motivations generally led to greater satisfaction and loyalty towards performances (H1, H2, H3). However, extrinsic motivation did not directly influence loyalty (H4). Nevertheless, both types of motivations were found to positively influence loyalty through performance satisfaction (H5, H8). While satisfaction with performances did not have a direct impact on community satisfaction (H6), audience loyalty was found to have a positive influence on community satisfaction (H7). Regarding motivations, performance satisfaction did not mediate the relationship between motivations and community satisfaction (H9). In the case of audience loyalty, intrinsic motivation showed mediating effects, while extrinsic motivation did not (H10). The process of motivation-satisfaction-loyalty-community satisfaction demonstrated a sequential pathway (H11). In conclusion, if local residents show interest and participate in non-profit performances, they develop a positive perception of the respective community. Therefore, performances provided at the local level should be recognized as crucial elements for the development of the community.

• Information Systems Review
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• v.22 no.1
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• pp.125-146
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• 2020

With the penetration of the Internet and e-commerce, a 'crowdfunding' has emerged as a new way of financing. Crowdfunding has the advantage for a person to able to a simple way to finance her/his an innovative product or service from crowd. However, the success rate for crowdfunding projects is less than half. In this study, we introduce social exchange theory to explore the impact of trust and perceived psychological risk on the intention to participate in a crowdfunding website. Different from previous studies that have focused on a crowdfunding creator, we consider two different perspectives of a project creator and a project supporter. In addition, we compare perceptions of crowdfunding in different cultural contexts by conducting survey in two different countries Korea and Austria. Result shows that trust in recommendation and trust in website have different impacts on the intention to participate from two different perspectives. It also shows that perception of the quality and transparency of information provided by crowdfunding website has greater impact on trust in Korea than that in Austria. In case of perception of psychological risk, it has a negative impact on Austria's intention to create or support a project. On the other hand, it has relatively small impact on the intention to support and does not affect the intention to create a project in Korea.

• Information Systems Review
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• v.23 no.4
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• pp.1-22
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• 2021

In the newly encountered economy caused by the Corona virus Disease-19, remote transaction becomes a new normal that disrupt traditional economic order. In the middle of the disruption, mobile tech is placed and remote finance on mobile is highly noticed and considered as an infra-tech to support the new ecology, In mobile finance. remote payment is becoming the most common service and personal identification on it is critical to operate the new service. There are various means of remotely identifying a person. Recently the use of biometric information is increasing. In this study, a correlation analysis was conducted on factors that effects to biometrics usage and the intention to use in remote personal identification. Variables for critical factor in the remote identification were classified into 4 groups such as Performance expectancy, Effort expectancy, Social influence, and Security. The empirical analysis based on the Unified Theory of Acceptance and Use of Technology (UTAUT) was conducted. The relationship between variables and the intention to use is also analyzed. In the study, stepwise regression analysis was conducted four times in which variables were adjusted in individual stage. As a result, the analysis suggests that performance expectancy, effort expectancy, social influence, security have positive effects for intention to use. Additionally, effort expectancy and security have moderating effects to intention to use depends on biometric authentication experience. The analysis has shown positive effect of variables grouped on the intention to use them. It also suggests that the intention to use biometric authentication will quickly grow. This study is expected to make a contribution to utilize and improve the use of biometric information in mobile payment.

• Information Systems Review
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• v.21 no.3
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• pp.131-149
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• 2019

As smart phones, tablets, and other digital devices become more pervasive, theoretical arguments around digital divide, which has previously focused on "access," is now expanding to effectively "utilize," actively "produce" and "share" information. Such discussion is significant because the impact on inter-personal and social networks depends on how digital divides are used, which can then recreate or exacerbate social inequality structures. This study examines the effect of individual's social relations and two types of social capital (i.e., bonding and bridging) on economic and socio-participatory usage of digital devices. An empirical analysis of dataset from 740 surveys reveals that the more horizontal the social relations of the individual, the more both bonding and bridging social capital increase. However, rather than the social relationship of the individual directly influencing the two types of digital device usage, it has an indirect effect on both economic and socio-participatory usage of digital devices. In particular, mediating effects of both bonding and bridging social capital exist in the case of economic usage of digital devices, whereas bonding social capital only has mediating effects on economic usage of digital devices. We discuss the role of social capital on digital devices usage and present the theoretical and practical implications.

• Fire Science and Engineering
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• v.22 no.3
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• pp.258-264
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• 2008

This study proposes the experimental methods which shows various guidelines for systematic study of surface forest fuels. The thermal characteristics of surface fire fuels such as Quercus Variabilis and Pinus Densiflora fallen leaves are measured using TGA and Oxygen Bomb Calorimeter. Both of them are common species of Korean forest. Also the combustion characteristics of surface fire fuels are analysed according to the methods which are commonly used in Pool Fire analysis. The measured parameters are gas velocity, temperature, flame height, heat release rate and mass loss rate. A system is designed to simulate the surface fire. Methods and results are shown for the application of forest fire study.

• Journal of Digital Convergence
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• v.11 no.12
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• pp.747-759
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• 2013

This study posits the activities of the fandom as information behavior: information producing, information diffusion, information sharing. The authors identify the underlying motivation and needs which lead fandom to these behavior on the basis of contents theory. In particular, the manner in which the those needs influence the information behavior of fandom is explored. The data used in this study came from various Fan Caf$\acute{e}$s which are communities of star fan. The results from the survey shows that the fandom is a kind of culture closely connected to social needs. Fandom can be viewed as an important driving force in the entertainment industry as they are co-creating the value in entertainment market.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.408-408
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• 2012

반세기가 지나는 동안 우리는 반도체의 크기가 계속해서 작아지는 것을 경험해왔다. 반도체 디바이스들의 차원이 100 nm 이하로 작아지면서, 나노와이어나 나노튜브로 이루어진 나노 소자들은 필연적으로 양자효과[1] 같은 저차원효과가 나타나게 된다. 특히 1차원 반도체 구조에서는 전자상태 밀도의 변화에 수반되는 전자-포논의 상호작용이 감소되어 전자이동도가 증가할 것으로 예측되었고, 이러한 이동도의 증가는 그동안 나노와이어나 나노튜브의 전기 전도도 증가가 일어난 실험적 데이터를 설명하는 이론적 받침이 되었다[2]. 한편 일차원 반도체 구조 체에서는 채널의 저차원화에 따른 전기장의 불균일성이 심화되고 이로 인하여 벌크와 매우 다른 전기수송 특성이 나타날 수 있는데 이러한 점이 그동안 간과되어 왔다. 본 연구에서는 시뮬레이션을 통하여 양자효과를 배제한 정전기적인 저차원 효과만으로도 전기 전도도가 증가할 수 있음을 보이고자 한다. 우리는 푸아송 방정식과 표동-확산 방정식을 SILVACO사의 ATLAS 3D 시뮬레이터를 이용하여 풀었다. 이 시뮬레이션에 사용된 실리콘 나노와이어는 길이를 $2{\mu}m$로 고정시키고 다양한 정사각형 단면적을 가진 구조로 하였다. 여기서 정사각형의 한변을 10nm 에서 100 nm까지 변화시켰다. 실리콘 채널의 도핑농도가 $1{{\times}}1016cm-3$일 경우, 낮은 전압, 즉 < 0.5 V 이하 영역에서는 벌크와 같은 선형적인 전류-전압 특성이 나타나지만, 그 이상의 전압 영역에서는 전류-전압 그래프가 위로 휘어지며(super-linear) 전기전도도가 확연히 증가함을 알 수 있었다. 예를 들어 2 V에서는 벌크에 비하여 흐르는 전류가 2배나 더 향상되었다. 이런 비선형적인 성질은 높은 전압을 인가하였을 때 나노와이어 채널 전반에 걸쳐 charge neutrality가 깨지게 되고 전하밀도가 증가하여 전도도 증가가 일어나는 것으로 밝혀졌다. 이 결과는 기존의 나노선에서의 전기전도도 증가 현상을 설명할 수 있는 대안을 제공할 수 있다.

• Journal of Digital Convergence
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• v.10 no.5
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• pp.7-17
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• 2012

This paper identifies the determinants of adoption and diffusion of e-government services, and examines the causal relationship among the variables of adoption behavior. The main findings, based upon survey responses from service users, are as follows: first, both the value of service and the socially influencing factor have the positive effect to the intention of utilizing services. Second, the socially influencing factor has the indirect effect to the intention of utilizing services, because it positively affects the value of service. The interaction factors, however, do not directly affect the intention of utilizing services. These interaction factors indirectly affect the intention of utilizing services through the path which increases the value of service, and its effect is larger than the socially influencing factor.

• Journal of Korea Society of Industrial Information Systems
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• v.22 no.3
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• pp.49-61
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• 2017

Due to Proliferation of Mobile Devices, the Global Mobile Application (App) Market is Set to Continue its Impressive Growth Trajectory. However, like other Digital Contents, Prevalent Piracy of Smartphone Apps has Become One of the Major Obstacles to the Growth of the Newborn App Industry. The Objective of this Study is to Examine and Better Understand the Effects of Factors Which has been Known to Influence PC Software Piracy. A Research Model Explaining the Impact of Various Factors to Smartphone App Piracy Attitude and Intention is Constructed Based on Theories of Ethical Behavior. A Survey of College Students was Conducted to Test the Research Model. Findings Show that PC Software Piracy Habit and Attitude have Significant Effects on Smartphone Piracy Attitude and Intention. Beliefs Concerning Judicial and Performance Risks Due to Piracy have Little Effects on Smartphone App Piracy Attitude.