• International journal of advanced smart convergence
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• v.4 no.1
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• pp.71-87
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• 2015

Mobile users want to be provided with undisrupted network services when they navigate on the Next-Generation (NG) wireless networks. For that, interlocking with a heterogeneous network is important, but there have been few studies on the method for guaranteeing global mobility. Thus, this paper proposes the Proxy-LMA technique, the mobile IP-based global inter-networking system, to enhance global mobility and interoperability within the Next-Generation (NG) network environment. The purpose of the proposed Proxy-LMA system is to expand the boundary of the mobility with regards to the existing mobility management protocol (PMIPv6 and MIPv6) in order to guarantee global mobility and interoperability within the heterogeneous network environment. The results of the performance evaluation showed that the proposed Proxy-LMA system was more efficient than other methods from the standpoint of signaling cost and delay in the heterogeneous network environment.

• International Journal of Safety
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• v.2 no.1
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• pp.12-16
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• 2003

In Part 1, the flame structure of the counterflow nonpremixed flames computed by using Fire Dynamics Simulator was compared with that of OPPDIF for different concentrations of methane in the fuel stream. In this study, comparisons were made for the global strain rate that is an important parameter for diffusion flames for further evaluation of FDS. At each of the three fuel concentrations, $20% CH_4＋ 80% N_2, 50% CH_4 ＋ 50% N_2, 90% CH_4 ＋ 10% N_2$ in the fuel stream, the temperature and axial velocity profiles were investigated for the global strain rate in the range from 20 to $100s^{-1}$. Changes in flame thickness and radius were also compared with OPPDIF. There was good agreement in the temperature and axial velocity profiles between the axisymmetric simulations and the one-dimensional computations except for the regions where the flame temperature reach its peak and the axial velocity rapidly changes. The simulations of the axisymmetric flames with FDS showed that the flame thickness decreases and the flame radius increases with increasing global strain rate.

• Journal of Information Display
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• v.8 no.1
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• pp.26-31
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• 2007

This paper presents ergonomic approaches to editing and evaluating content for 3D displays. Two systems, a nonlinear editing system and an evaluation system, were developed to improve viewing safety and comfort for 3D content observers and provide better usability for the creators from the viewpoint of ergonomics.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.2
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• pp.153-163
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• 2020

After launching the GOCE (Gravity Field and Steady-State Ocean Circulation Explorer) which obtains high-frequency gravity signal using a gravity gradiometer, many research institutes are concentrating on the development of GGM (Global Geopotential Model) based on GOCE data and evaluating its precision. The precision of some GGMs was also evaluated in Korea. However, some studies dealt with GGMs constructed based on initial GOCE data or others applied a part of GNSS (Global Navigation Satellite System) / Leveling data on UCPs (Unified Control Points) for the precision evaluation. Now, GGMs which have a higher degree than EGM2008 (Earth Gravitational Model 2008) are available and UCPs were fully established at the end of 2019. Thus, EIGEN-6C4 (European Improved Gravity Field of the Earth by New techniques - 6C4), GECO (GOCE and EGM2008 Combined model), XGM2016 (Experimental Gravity Field Model 2016), SGG-UGM-1, XGM2019e_2159 were collected with EGM2008, and their precisions were assessed based on the GNSS/Leveling data on UCPs. Among GGMs, it was found that XGM2019e_2159 showed the minimum difference compared to a total of 5,313 points of GNSS/Leveling data. It is about a 1.5cm and 0.6cm level of improvement compare to EGM2008 and EIGEN-6C4. Especially, the local biases in the northern part of Gyeonggi-do, Jeju island shown in the EGM2008 was removed, so that both mean and standard deviation of the difference of XGM2019e_2159 to the GNSS/Leveling are homogeneous regardless of region (mountainous or plain area). NGA (National Geospatial-Intelligence Agency) is currently in progress in developing EGM2020 and XGM2019e_2159 is the experimentally published model of EGM2020. Therefore, it is expected that the improved GGM will be available shortly so that it is necessary to verify the precision of new GGMs consistently.

• Quality Improvement in Health Care
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• v.1 no.1
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• pp.26-31
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• 1994

• Journal of Korean Society for Quality Management
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• v.42 no.2
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• pp.253-264
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• 2014

Purpose: The aim of this study is to gain a competitive advantage in the global marketplace by examining the current situation of three domestic Food Dehydrator companies' products. Food Dehydrators are sort of small domestic appliances(SDA), first introduced by Korean companies. Furthermore, this study suggests the improvement plans in the rapidly changing world situation. Methods: Evaluate through comparing three domestic Food Dehydrator companies' products based on the PQI(Premium Quality Index) model, developed by product quality evaluation experts group. Results: At first, we classified evaluation factors into three parts - usability quality, emotional quality - and each of the factors includes sub factors. Under this condition, the results of this study are as follows; the brand quality is remaining at a high satisfaction level compare to other two factors but emotional quality is assessed to be low. This study has shown at customers consider brand and usability quality factors as the most important factor due to the nature of the product. Conclusion: As the possibility of increasing customer needs such as product design and sensitive quality besides usability quality has risen in a competitive global market, the manufacturing companies in Korea are recommended to put forth the necessary effort to improve their product quality, especially in terms of emotional quality.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.7
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• pp.2769-2784
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• 2020

This paper aims to compare the scenic images of four ancient Chinese cities including Lijiang, Pingyao, Huizhou and Langzhong, so as to provide specific development strategies for the ancient cities. In this paper, the ancient cities' scenic images are divided into three sub-indexes and eight evaluation dimensions. Based on this, the study first uses Python software to collect tourists' online comments on the four ancient cities. Then, the social network analysis method is used to build a high-frequency keywords matrix of tourist comments and the R language is used to generate a visual network graph. After this, the entropy weight method is used to determine the weights and values of eight evaluation dimensions. Finally, the tourists' overall satisfaction indexes of the four ancient cities are calculated accordingly. The results show that (1) the overall satisfaction of Lijiang is the highest, while that of Huizhou is the lowest; (2) from the weight of each evaluation dimension, it can be seen that tourists care more about the national culture and historical culture; (3) from tourists' satisfaction index on each evaluation dimension of the four ancient cities, we can find that the four ancient cities has their own advantages and disadvantages in tourism development. (4) local tourism-related institutions should strengthen their advantages and improve their deficiencies so as to enhance tourists' overall image of the ancient city.

• Journal of Korean Society for Quality Management
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• v.50 no.4
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• pp.863-876
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• 2022

Purpose: The purpose of this study is to propose the product quality satisfaction index based on multiple linear regression using customer reviews. Methods: The proposed framework is composed of four steps. First, we collect online reviews and divide it into insight phrases. The insight phrases are classified using product attribute dictionary and sentiment analysis is conducted. Second, the importance of attributes is calculated in consideration of both regression coefficient and frequency. Third, the positive rate is calculated concerning sentiment analysis result. Therefore, the quality satisfaction index is measured by the weighted sum of importance and positive rate in the last step. Results: We conduct a case study using 2-years(2020, 2021) of Samsung TV reviews to confirm the effectiveness of the proposed methodology. As a result, we found that Picture quality is the most crucial attribute in TV evaluation. The importance of Gaming and content has grown up as the positive rate has also increased. Therefore, the overall satisfaction of TV has increased in 2021 compared to 2020. Conclusion: The result of this study shows that the proposed index reveals the customer's mind efficiently and can be explained by the importance and positive rate of each attribute. By using the proposed index, companies are able to improve and the priority of improvement can be determined.

• Journal of Drive and Control
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• v.14 no.3
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• pp.8-17
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• 2017

With automobiles sharply increasing in numbers worldwide, we are faced with critical social issues such as traffic accidents, traffic jams, environmental pollution, and economic inefficiency. In response, research on ITS is promoted mainly by regions with advanced automotive industry such as the U.S., Europe, and Japan. While Korea is working on moving forward in the global market through developing and turning to global standards systems related to ASV (Advanced Safety Vehicle), the country is not fully prepared for such projects. The purpose of ACC (Adaptive Cruise Control) is to control a vehicle's longitudinal speed and distance and minimize driver workload. Such a system should be valuable in preventing accidents, as it reduces driver workload in the 21st-century world of telematics created by development of the automobile culture industry. In this light, the thesis presents a method to test and evaluate ACC system and a mathematical method to assess distance. For the proposed test and evaluation, theoretical values are tested with vehicle test and a database is acquired, by using vehicles equipped with an ACC system. Theoretical evaluation criteria for developing ACC system may be used and scenario-specific evaluation methods may find useful application through testing the formula proposed by comparing the database and mathematical method.

• Journal of Science and Technology Studies
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• v.15 no.2
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• pp.33-64
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• 2015

World Wide Views (WWViews) on Climate and Energy was an experiment of public deliberation which was held in 77 countries with over 10,000 global citizens on June 6, 2015. The coordinator of this project (the Danish Board of Technology with Missions Publiques and the French National Commission for Public Debate) developed the overal procedure, and local partners implemented the actual events in each country on the same day. The coordinator gathered the results of the events from all local sites in order to submit them as global citizens' voice to the COP21 negotiations at the United Nations Framework Convention on Climate Change (UNFCCC) in Paris. This study examines the extent to which such new method of WWViews, standardized at global level to be implemented in different local contexts, achieves its quality of public deliberation (representativeness, transparency, impartial inclusion, deliberativeness, influence) by evaluating the Korean WWViews held in Seoul.