• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.9
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• pp.907-915
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• 2008

The computational fluid dynamic analysis has been conducted for the thermo-chemical flow field in an arcjet thruster with mono-propellant Hydrazine (N2H4) as a working fluid. The Reynolds Averaged Navier-Stokes (RANS) equations are modified to analyze compressible flows with the thermal radiation and electric field. the Maxwell equation, which is loosely coupled with the fluid dynamic equations through the Ohm heating and Lorentz forces, is adopted to analyze the electric field induced by the electric arc. The chemical reactions of Hydrazine were assumed to be infinitely fast due to the high temperature field inside the arcjet thruster. The chemical and the thermal radiation models for the nitrogen-hydrogen mixture and optical thick media respectively, were incorporated with the fluid dynamic equations. The results show that performance indices of the arcjet thruster with 1kW arc heating are improved by amount of 180% in thrust and 200% in specific impulse more than frozen flow. In addition thermo-physical process inside the arcjet thruster is understood from the flow field results.

• Journal of Korea Water Resources Association
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• v.39 no.6 s.167
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• pp.511-520
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• 2006

Riverbank filtration is a natural process, using alluvial aquifers to remove contaminants and pathogens in river water for the production of drinking water. In Korea, most of the drinking water is supplied by surface water in-take. However, maintaining the quality of the drinking water becomes more and more difficult due to the increase of contamination. In riverbank filtration, the understanding of contaminant transport is an important task for the production of high quality drinking water and for the maintenance of facilities. In this paper, the transport behavior of hydrophobic organic contaminants is investigated when contaminants coexist with dissolved organic matter (DOM) and bacteria. In the developed model, the aquifer is thought of as a four phase system: two mobile colloidal phases, an aqueous phase, and a stationary solid matrix phase. The model equations are solved numerically for various situations. Results indicate that the presence of colloidal matters can enhance the mobility of contaminant significantly and that partitioning coefficients play an important role in the process.

• The Journal of the Korea Contents Association
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• v.13 no.12
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• pp.966-973
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• 2013

It has been frequently asked the question not only by academicians but also by practitioners whether employment flexibility can be compatible with employment stability. This study tries to find the answer by investigating the German model of employment flexibility practices and job stability policies. The German model of employment flexibility is mainly based on working-time accounts and short-time work programs. It is found that social partnership and government support have played a crucial role to stabilize German labour market. Workers, employers, and government have harmoniously interplayed in order for overcoming the economic hardship. Adapting the German experience of overcoming economic turbulence by introducing employment flexibilization can help Korean firms. However, it is important to recognize that there are some differences in practices of labour relations, cultural and social background while applying the German practices.

• Archives of design research
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• v.15 no.4
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• pp.149-156
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• 2002

The success of a product is only possible on the basis of user preference for products and the user preference for products is greatly influenced by the design. Designers have to understand user preference and convert it into the combination of specified design attribute, and after that they should design products which have the image that they want to get. Then the product will be sure to be a hit. Therefore, on the point of view of design, it is necessary to find oui definitely the consumer preference frame : the relationship among design preference - design images - design attribute. This study will give you guidelines on which designers can select and design some more objective and reliable design factors, finding out the relation of cause and effect by which they can know what kind of product designs their consumers like and how the popular image which that products offer is composed of. Therefore, in this study, after we developed the consumer response framework which is proposed by Bloch(1995) : distinct relationship model among preference - design image adjective - design factors, we analyzed the relationship among preference-design image adjective - design factors through the empirical researches. And then we give the way of design.

• Journal of Food Hygiene and Safety
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• v.14 no.4
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• pp.386-396
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• 1999

Commonly eaten fish, meat and other protein-containing foods show some level of mutagenic activity following normal cooking such as broiling, frying, grilling, roasting etc. The main food mutagens found in cooked products are“heterocyclic aromatic amines”. Several of them have been shown to be carcinogenic in rodent and suggested to be relevant for human cancer etiology. This review summarizes the chemistry, formation, occurrence and toxicity of food-borne heterocyclic aromatic amines. Factors that influence the formation of them are also discussed with special emphasis on dietary factors. From a health safety point of view, it is desirable to estimate the intake of heterocyclic amines via foods, and reduce or prevent the formation of food mutagens.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.1
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• pp.35-44
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• 2010

In this paper, we propose a method about producing skin color model adaptively in input image and face detection. The principle process which we proposed is finding eyes candidates by applying the eye features to neural network, and then using the around color to find the distribution of color value. There will be a verification process that producing face region by using color value distribution which is detected as skin region and find mouth candidate in corresponding face region; if eye candidate and mouth candidate's connection structure is similar with face structure, then it can be judged as a face. Because this method can detect skin region adaptively by finding eyes, we solve the rate of false positive about the distorted skin color which is used by existing face detection methods. The experiment was performed about detecting the eye, the skin, the mouth and the face individually. The results revealed that the proposed technique is better than the traditional techniques.

• The Journal of the Korea Contents Association
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• v.13 no.5
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• pp.199-209
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• 2013

The purpose of this research is to develop elements of place branding and correspondent evaluation indicators for place brand strategy making, analysis and its evaluation. First, I criticise that previous research employed unclear and limited evaluation elements. I then suggest an plausible evaluation system and evaluation indicators through a theoretical proof for place branding under the concept of place-based value. Interviews with specialists for case evaluations were carried out in an effort to approve the plausibility of this suggested evaluation system. As an extension, a direction is suggested for a general and effective place branding that would satisfy a diversity of places, which could hopefully contributes for the development of future city brand and marketing evaluation criteria. Creating a specialized place brand requires precise understanding and evaluation on the place characteristics that should directly contribute to the strategy making based on the situatedness suggested by the place which meets an appropriate place branding category. In addition, a successful place branding requires active and effective communication among the participating members of interest and sustainable maintenance systems.

• The Journal of the Korea Contents Association
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• v.16 no.2
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• pp.546-557
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• 2016

Tooth carving practice is required for novice learners in dentistry to understand dental morphology and acquire clinically underlying skills. Tooth carving practice is more effective when sequential models can be observed. The purpose of this study is to suggest a tooth carving practice model and to develop a mobile practice supporting tool based on tutorial providing 3D modeling information about steps of tooth carving. As a result, tooth carving practice model consists of the class activity including tooth information lecture and practice and mobile seamless learning connecting learners' practice and regular learning with the mobile tutorial tool. The mobile tutorial tool is implemented with tooth morphology dictionary, tooth carving practice/training tutorial, and 3D tooth modeling. The experts' evaluation on the developed contents shows that the content and function are valid(content validity: 5.0, interface validity: 4.53). Therefore, the mobile tutorial tool is suitable for supporting mobile seamless learning for tooth carving practice. Further researches are expected to be conducted to develop instructional models utilizing ICT and mobile contents in dentistry.

• The Journal of the Korea Contents Association
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• v.20 no.10
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• pp.284-293
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• 2020

The rapid progress of AI technology gives us the expectation to solutions to various problems in our society, and at the same time, it gives us anxiety about the side effects that can occur if AI develops beyond human control. This study was conducted in the early 20s with less objection to advanced devices. We attempted to provide clues to understand thoughts and attitudes of the targets about the future environment that will be brought by AI through the process of finding intent the acceptance of strong AI technology. For this, we applied the Theory of Planned Behavior, and further expanded this research model to identify factors affecting the attitude toward AI. As a result, the attitude toward AI and perceived behavioral control had a significant effect on the intention to use to strong AI. In addition, we found that the expectation of the benefit of improving task performance and the anxiety on the threat of relationship disturbance had a significant effect on the attitude toward AI. This study suggests implications for AI-related companies establishing the direction of technology development and for government setting a policy direction for AI adoption.

• Journal of KIISE:Software and Applications
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• v.37 no.2
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• pp.95-103
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• 2010

Improving the competitiveness of software products in the market involves procuring the means to design software architecture that deliver qualities necessitated by stakeholder requirements within allocated budget, thereby improving the cost-effectiveness of the end product. Currently, software architecture evaluation methods are used to predict and review qualities inherent in software architecture designs and to choose a candidate architecture that delivers desired qualities. Existing software architecture evaluation methods, however, fail to address the cost considerations dependent on the architecture chosen for product implementation. In this paper we suggest a cost estimation method for software architecture which adapts the cost drivers in the software cost estimation model COCOMO II to support cost estimation during architecture evaluation. The suggested method can be performed in coordination with existing software architecture evaluation efforts and supplements existing architecture evaluation techniques with guidelines for identifying and evaluating cost drivers in candidate software architectures without incurring extra overhead. The accuracy of the cost estimation using the suggested method is verified through application of the method to the architecture candidates used in RPS (Robot Patrol System), a surveillance embedded system.