• The Journal of Engineering Geology
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• v.13 no.1
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• pp.17-27
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• 2003

In this study, a phenomenon of saltwater intrusion was monitored under various conditions regarding recharge and pumping rate using time domain reflectometry for a laboratory scale unconfined aquifer to verify the basic theory behind seawater intrusion and to investigate movement of salt-freshwater interface in accordance with the ratio of pumping and recharge rate. Results showed that a thick mixing zone was formed at the boundary instead of a sharp salt-freshwater interface that was assumed by Ghyben and Herzberg who derived an equation relating the water table depth $(H_f)$ to the depth to the interface $(H_s)$. Therefore our experimental results did not agree with the calculated values obtained from the Ghyben and Herzberg equation. Position of interface which was adopted as 0.5 g/L isochlor moved rapidly as the Pumping rate $(Q_p)$ increased for a given recharge rate $(Q_r)$. In addition, interface movement was found to be about 7 times the ratio of $Q_p/Q_r$ in our experimental condition. This indicates that Pumping rate becomes an important factor controlling the seawater intrusion in coastal aquifer.

• Journal of Korea Game Society
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• v.15 no.1
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• pp.171-184
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• 2015

Looking at the existing game-related research, innumerable researches such as game acceptance, user satisfaction, continuance intention, wold-of-mouse intention have been carried out. However, there was no cases that applying the concept of service recovery in game researches. The purpose of this study is to evaluate the impact on the characteristic of the mobile social network game that based on domestic mobile social network game platform which focusing on KakaoTalk games on the service recovery. In addition, the study analyzed the characteristic factors of mobile social network game on the basis of Organizational Equity Theory and Innovation Diffusion Theory to identified the causal relationship between those factors and service recovery. As a result, except the independent variable-compatibility, all of the characteristics factors of mobile social network game showed direct or indirect effects on service recovery. The results of this study are expected as a reference for presenting a new business model, reducing risk factors and enriching the related research of the gaming industry.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.3
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• pp.111-121
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• 2015

Owing to the wide distribution of smart devices, more people enjoy online games. Previous research related to online game has mainly focused on the factors that increase users' intention to reuse and less focused on the influence of restrictions toward online game misbehavior. This study proposes a research model that considers factors that either increase or decrease the use of online games and presents the outcomes. The research results showed that: (1) Restriction policy had no impact on online game users' feelings of pleasure and arousal. (2) Restriction system had negative impact on users' feelings of pleasure and arousal. (3) In an environment where online game misbehavior was restricted, users' emotional states still had positive influence on users' intention to reuse. This research results implies that in order to lead to healthy online game environment, compared to repressive and systematic restriction methods, it is preferable to establish restriction policies that have no negative impact on users' emotional states and to change users' perception through education, so to achieve successful restrictions toward online game misbehavior without jeopardizing revitalization of online game industry.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.12
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• pp.1147-1152
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• 2013

In this study, the effect of an insulation coating on the start time of a linear region is theoretically investigated when an insulation-coated hot-wire is used for the transient hot-wire method (THWM). For this purpose, important parameters affecting the start time of the linear region are presented from an analytical solution of temperature-rise for an insulation-coated hot-wire. Furthermore, a critical time to ignore the influence of important parameters is studied. The theoretical results indicate that the effect of the insulation coating rapidly disappears with a decrease in the wire radius, coating thickness, thermal diffusivity of insulation material or an increase in the thermal conductivity of the insulation material. The results of this study will be helpful for selecting a proper start time of the linear region for the THWM using insulation-coated hot-wires.

• Membrane Journal
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• v.11 no.1
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• pp.14-21
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• 2001

Rapid backpulsing to reduce membrane fouling of hollow fiber ultrafiltration module (polyacrylonitrile with 50000 l'vlWCO, 1.4 rom OD and 0,9 mm ID) was studied with latex solutions. Values estimated by a theoretical model were compared with the ones obtained from the systems with or without backpulsing, Specific Cake resistance, time consUmt for cake growth, diffusion coefficient, and the rate constants of fnur fouling models; the complete, intermediate. standard blocking and cake filtration were calculated to obtain the theoretical values. High frequency backpulsing gave net increase of fluxes by 40~120%. Fluxes predicted by the model were in good agreement with experimental ones within 14% error bound, The optimum backpulsing strength was acquired at 20% in the ranges of 20~40% strength and the optimum frequcncv was acquired at 2 Hz in the ranges of 0.67~3 Hz.

• Journal of Science and Technology Studies
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• v.13 no.2
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• pp.71-110
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• 2013

As a patient has recently been recognized as not a passive object but a subject of medical services, various attempts are being made to strengthen the status of a patient. Medical communication which has been led by a doctor so far is being made with a focus on a patient due to sovereignty of a consumer and activation of medical information. The purpose of this paper is to investigate the process to strengthen the status of a patient as a consumer of health care service through a patient association and consumer movement as medical information becomes public. As the patient centered medical service is creating a variety of health care service market using IT technologies, it has contributed to the improvement on asymmetry of medical information. As the expansion of IT fusion health care market is bringing the fundamental change into the traditional relationship between a doctor and a patient, the medical service market is being re-organized. A patient centered medical service such as expansion of mobile health care model led by a patient is being accelerated.

• Korean journal of communication and information
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• v.48
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• pp.280-305
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• 2009

By conceptualizing UCC users' active behavior, this study newly presents two key concepts, 'self-expression' and 'artistic activity' of UCC users. Then, this study suggests a research framework to analyze text, image, and video UCC adoption processes by integrating those concepts with already-built UCC research tradition. Using the framework, we found that individuals who has a hard time expressing themselves in reality are likely to have a favorable attitude toward UCC, and the stronger the faith about the justice of self-expression and its freedom, the more the favorable attitude toward UCC. Furthermore, we confirmed that individuals who are very interested in artistic activity, and individuals who has high self-efficacy to their artistic talent are likely to participates more in UCC production. The role of other factors such as perceived enjoyment, the perception of critical mass of UCC adoption, and subjective norm also were discussed with limitations of this study.

• The Journal of the Korea Contents Association
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• v.13 no.1
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• pp.64-72
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• 2013

In this study, we contemplated types, essence, characteristics of text data which is material for visual expression of text visualization part of data visualization research and also analysed the multidirectional means of expressive approach for it. Studies of text visualization are spread dramastically under the influence of computer development, open data, wide use of visualization tools, etc. For these reasons, text visualization works have been creating as art works or output of research through various inter-discipline convergent research with engineering, art, humanities, sociology, etc. Nevertheless the theoretical studies on text data itself and its visualization, and also systematic analysis of its approach are rarely made. Data is target of understanding and interpretation, and it has infinite information and possibility with process and approach for it. Considering the attainable status of data in future human society, text visualization which is convergent academic field of study starting with understanding and interpretation of data needs further methodological research and theoretical accumulate.

• Water for future
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• v.28 no.4
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• pp.185-194
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• 1995

The objective of this study is to explore scale problem and to analyze the relations between scale and geomorphologic parameters of the rainfall-runoff model. Generally, measurement and calculation of geomorphologic parameters rely on and are sensitive to the resolution of source information available. Therefore, rainfall-runoff models using geomorphologic parameters should take account of the effects of the map scale used in their development. The derived rainfall-runoff model considering scale problem in this research is the GIUH type model, that is a basin IUH consisting of the channel network response and hillslope response. The cannel network response is computed by means of the diffusion analogy transformed from linearized St. Venant equation and hillslope response is calculated by 2-parameter gamma distribution function. Representing geomorphologic structure of the channel network and initial distribution of its response is width function. This width function is derived by fractal theory and Melton's law to consider scale problems and is weighted by the source location function (SLF) proposed in this research to increase the applicability.

• Informatization Policy
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• v.18 no.4
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• pp.3-21
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• 2011

Knowledge ecosystem means a dynamic knowledge circulation, including knowledge creation, exchange and sharing and utilization. It is also the field of knowledge practice, which creates interactions in knowledge exchange between people and groups. The key premises of knowledge ecosystem, based on the nature of general ecosystems, can be characterized as follows: first, it primarily focuses on social networks between people and organizations participating in the process of knowledge circulation; secondly, knowledge ecosystem thrives on diversity of knowledge; and thirdly, it is significant for selection of valuable knowledge and adoption of appropriate knowledge. This review attempts to make a systematic examination of a wide range of existing studies on knowledge ecosystem. In so doing, it is expected to provide a basis for further inquiry into more critical and complicated issues. Although the scarcity of existing research-at least those in Korea-may limit the implications of findings, this review offers a set of suggestions for future research.