• Journal of the Korea Computer Industry Society
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• v.5 no.1
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• pp.131-146
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• 2004

As Electronic Commerce(EC) has been emerged and has developed, many researchers have tried to establish EC framework for automated contract and negotiation using agent technologies. Traditional researches, however, often had limitations. They often enforced the user's participations during the automated contract process of agents. They also could only consider a few of the user's requirements for a specific goods and did not have supported the procedures and methodologies for making the best contract. In this paper, we propose business model on EC based on multiagents to overcome the defects of the previous researches. We apply CSP techniques to brokerage process to satisfy various preferential requirements from the user. We also propose efficient negotiation mechanism using negotiation model of game theory. The contract candidates automatically negotiate and mediate in terms of their benefits through the proposed negotiation mechanism. For the optimal brokerage and automated negotiation, the agents process activities for contract on three layers, which are called competition layer, constraint satisfaction layer and negotiation layer in the proposed model. We also design the message driven communication protocol to support the automated contract among the agents. Finally, we have implemented prototype systems applying the proposed model and have shown the various experimental results for efficiency of the proposed model.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.4
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• pp.330-336
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• 2015

Purpose: This study evaluated the effect of loss of interproximal papilla, creating an undercut, on the accuracy of impression materials. Materials and methods: Two addition type silicone impression materials ($Extrude^{(R)}$ Speed Wash, $Imprint^{TM}$ II Quick Step Light Body) and one alginate impression material (Cavex Impressional) were used to make impressions of a maxillary master model simulating clinical conditions with or without interproximal papilla. Stone was poured in the impressions and working casts were fabricated. A total of 6 groups with 6 working casts in each group were scanned using 3-dimensional optical scanner. The accuracy of the impressions was assessed by measuring the dimensional changes (${\Delta}I$ (%)) of 6 distances on working casts compared to a master model with a 3-dimensional digitizing and inspection software. The data were analyzed by two-way ANOVA (P<.05). Results: Three of 6 distances showed statistically significant differences among the impression materials. Only 1 of 6 distances in alginate impression showed a statistically significant difference between casts with and without interproximal papilla (P=.047). Conclusion: The presence of undercut due to loss of interproximal papilla did not significantly influence the dimensional accuracy of addition type silicone and alginate impression materials.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.6
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• pp.1753-1764
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• 2014

Numerical flow simulation models in the riverine environments have been widely utilized for analyzing flow dynamics in various degrees in researches and practical applications. However, most of the simulated results have been validated based on the data from indoor experimental models or very limited in-situ measurements. Therefore, it has been required to more accurately validate the performance of the numerical models in terms of the detailed field observations. In particular, it was also hard to validate the performances of the existing numerical models in the real meandered river channels that encompass more sophisticated flow and geometric structures. Recently, advancements of the modern flow measuring instrumentations such as acoustic Doppler current profilers (ADCPs) enabled us to efficiently acquire the detailed flow field in the broad range of river channels, thus that it became to be possible to accurately validate any numerical models with the field observations. In this study, based on the detailed flow measurements in a actual meandered river channel using ADCP, we validated FaSTMECH model in iRIC in terms of water surface elevation, which is relatively new but began to get highlighted in the research areas. As the validation site, a meandering channel in River Experiment Center of KICT was chosen, which has 6.5 m of width, 0.38m of flow depth, 1.54 m3/s of flow discharge, 0.61 m/s of mean flow velocity, and 1.2 of sinuosity. As results, whereas the FaSTMECH precisely simulated water surface elevation, simulated velocity field in the bend did not match well with ADCP dataset.

• Journal of Korea Society of Industrial Information Systems
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• v.28 no.1
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• pp.57-69
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• 2023

In a situation where digital transformation using artificial intelligence is active around the world, the growth of domestic AI companies or AI industrial ecosystems is slow. Where a large amount of government funds related to AI are being invested to overcome the difficult economic situation, systematic research on the effect is insufficient. So, this study aimed to examine the policy effectiveness of the government artificial intelligence solution voucher support project for small and medium-sized enterprises (SMEs) using Propensity Score Matching (PSM) and Difference-in-Differences (DID) on the financial performance of beneficiary companies. For empirical analysis, PSM-DID analysis was performed using sales performance since 2019 for 461 companies with a history of voucher support among the AI SMEs data released by the National IT Industry Promotion Agency. As a result of the analysis, the beneficiary companies' asset growth, salary, and R&D expenses increased overall after government support, and no significant contribution could be confirmed in terms of profits. This study suggests that the voucher policy business directly contributed to the company's growth in the short term, but it requires a certain period of time to generate profits.

• Fire Science and Engineering
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• v.26 no.6
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• pp.109-117
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• 2012

The author analyzed and compared the relationship mechanism among measured variables effecting to posttraumatic stress and posttraumatic stress, psychological wellbeing, and depression in the case of 360 policemen and 360 firefighters working in Korean police stations and fire stations by the structural equation modeling. The results showed that firefighters' posttraumatic stress deteriorated psychological wellbeing and depression more than policemen's posttraumatic stress did. In conclusion, systematic prevention and management program for posttraumatic stress and mental health of public servants are needed.

• Journal of Digital Convergence
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• v.10 no.6
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• pp.49-59
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• 2012

This study is to explain why internet users are unconcerned with their privacy information. For this purpose, this study focuses on the Nate.com case. Nate.com recently suffered from external intrusion. They announced this fact to their users. However, users did not leave the Nate.com. To explain the reason, this study used a combination of qualitative and quantitative techniques. The grounded theory approach was used to analyze responses to open-ended questions answered by 240 Nate.com users. Using these responses, a survey instrument was developed. Survey results were analyzed using structural equation modeling. The conclusions and implications are discussed.

• Korean Journal of Construction Engineering and Management
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• v.3 no.3 s.11
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• pp.94-102
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• 2002

It expresses well result measurement system's the importance that 'It can not manage that can not measure.' In this way, there is no expressivity that express difficulty. While Corporation's tangible asset is possible measuring by specific amount of money of financial statement or loss and gain statement etc, Method of corporation's intangible asset measurement is much had been introduced, but some one is not presenting objective frame. This research did size of construction corporation's intangible Asset(Intellectual Asset) through knowledge asset storing accumulation model(XYZ model) that present in LG economy research institute so that do quantification objectively. Through this, can presume construction corporation's intrinsic value level.

• The Korean Journal of Applied Statistics
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• v.24 no.1
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• pp.103-114
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• 2011

Current series for testing stock market cointegrations tend to be restricted to analyzing the relations between stock market prices and may not be able to understand the whole picture of the variations in the stock market system. The nature of the variations in the stock prices, between the countries that experienced economic crisis and those did not, are different for a certain period of time, and accordingly excluding the potentially important variables in the stock market system causes statistical bias. This study considers domestic foreign exchange markets and financial markets in testing for the cointegrating relations of the stock prices in Korea and major investing countries. The results demonstrate the possibility of specification errors unless those markets are included in the statistical modeling process.

• Journal of the Korean Institute of Rural Architecture
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• v.11 no.2
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• pp.29-36
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• 2009

The recently research shows that the many tourists of Suanbo hot spring waters haven't satisfied the service. These reasons due to that they did not properly consider the satisfaction of tourists' services and index. However, satisfaction level of hot spring waters tourists is interacted complicatedly with various factors, the interactions are not easily identified. A structural equations model is adopted to capture the complex relationships among variables. In the model estimation, we used 140 survey data of Suanbo hot spring waters tourists. The SEM with several factors mentioned above as exogenous variables shows that they have complex and strong relationships. As results of a SEM, it was shown that variables influencing in pleasance are surrounding scenery, clean condition inside hot springs and congestion for use in satisfaction level most. Secondly, in case of kindness, attitudes of employees influence in satisfaction level most, followed by attitudes of residents and kindness of employees. Thirdly, in case of information, it was shown guidance on internal roads influencing in satisfaction level most, followed by guidance on owner drivers, guidance on surrounding tourist attractions and guidance on public transportation. Finally, a variable influencing in accessibility most is satisfaction level of public transportation.

• The Journal of the Korea Contents Association
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• v.17 no.9
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• pp.353-362
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• 2017

The purpose of this study aimed to investigate the mediating effect of self-esteem between attachment and depression in adolescents. The study specified theoretical assumptions based on internal working model and vulnerability model. The data were analyzed by structural equation modeling. A total of 2,058 adolescent data from 2015 Korean Children and Youth Panel Survey was used in this study. The results showed parent attachment, peer attachment, and teacher attachment did not have direct effects on adolescent depression, but have indirect effects. Self-esteem had direct and mediating effect on depression. The implications were discussed in relation to interpersonal relationships and self-esteem of adolescents for depression prevention.