• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.7
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• pp.1638-1656
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• 2013

The demand for multimedia streaming services is increasing rapidly. To meet this demand, there has been much research and many practical developments for providing multimedia services. A push-to-talk (PTT) service is one of the multimedia streaming services that have been deployed not only over IP multimedia subsystem (IMS) but also in peer-to-peer (P2P) overlay networks. The benefit of PTT has been demonstrated in the literature. However, the need for using PTT service in communication can be arbitrary among users, regardless what kind of PTT services they use. This demand does not support current PTT systems, so an expansion of PTT services still be limited. Moreover, the combination of PTT services in IMS and P2P networks will help operators to provide more scalable PTT services. Therefore, in this paper, we proposed a model to support PTT service interworking between IMS and P2P overlay networks. We also introduced our system design and some interworking service scenarios. We confirmed our architecture through implementation and testing.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.14-20
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• 2006

During the 11 year period of 1995-2005, there was about a 40% increase in the world copper demand mainly because of the Asian economic growth. In the increase, about a half was consumed by China. Most of the China's copper demand increase has been taken place over the final 5-6 years of that period. The growth is expected to continue for several years, and in 10 years or sooner the same situation is expected for India. Copper is the third metal in global demand, but its little abundance in the Earth's crust is not well recognized. From the production rate and the abundance, a copper shortage, or crisis, has a high probability than the other metals. Deep ocean mineral resources such as manganese nodules in the Clarion-Clipperton Fracture Zones, Kuroko-type massive seafloor sulfides (SMS), and cobalt-rich manganese crusts in the EEZ and the high sea areas have big potentials for the future sources. We need to re-evaluate their potentials as copper resources and other metals to realize their developments. The same situation is under progress in the hydro-carbon markets. Methane hydrates that are classified into non-conventional hydro-carbon resources have an important role as the future sources, too.

• Journal of the Korean Dietetic Association
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• v.16 no.3
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• pp.255-269
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• 2010

The purpose of this study was to investigate consumer awareness and demand related to country-of-origin labeling at restaurants, and to provide basic data to reexamine the need for current policies and to determine problems. The study found that 70% of the respondents thought that the implemented representation policy had improved food quality, and 81.3% of the respondents checked country-of-origin labeling at restaurants. In addition, 74.7% of the respondents answered that "reward for accusation" was appropriate policy. Regarding the degree of recognition of the meat importers, the respondents were well aware of the importing countries, but did not recognize the importing country of chicken. In terms of preference for meat importers, Australian beef was rated highest, but beef from the U.S. was ranked seventh. However, in preferences for pork and chicken, U.S. products were rated highest. According to the survey, in a question regarding the perception toward country-of-origin labeling, the respondents recognized that rice, beef, pork, and chicken were the targeted items. In addition, the respondents suggested that other food ingredients at restaurants should be designated as target items for country-of-origin labeling.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.1
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• pp.41-54
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• 2019

Although retailers deals with a large number of single-term inventory items, but few cases have been considered in the areas of practical decision making. However, recent moves to strengthen fair trade have created a real need for single-period inventory decision-making problems. This study addresses the problem of ordering quantity decisions that are expected to maximize profits using classical newsvendor models. The research target is data on seasonal and perishable products from retail. We also use data from retailers to actually apply the newsvendor model and calculate the results to compare performance. It also suggests solutions for estimating demand for products sold in order to apply newsvendor models that utilize actual demand ratio versus forecast demand. This study would like to examine the effectiveness of this research through data analysis and make some suggestions for applying it to reality.

• Communications for Statistical Applications and Methods
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• v.28 no.4
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• pp.393-410
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• 2021

The Korean Long-Term Care Insurance (K-LTCI) provides financial support for long-term care service to people who need various types of assistance with daily activities. As the number of elderly people in Korea is expected to increase in the future, the demand for long-term care insurance would also increase over time. Projection of future expenditure on K-LTCI depends on the number of beneficiaries within the grading system of K-LTCI based on the test scores of applicants. This study investigated the suitability of mixture distributions to the model K-LTCI score distribution using recent empirical data on K-LTCI, provided by the National Health Insurance Service (NHIS). Based on the developed mixture models, the number of beneficiaries in each grade and its variability under the current grading system were estimated by simulation. It was observed that a mixture model is suitable for K-LTCI score distribution and may prove useful in devising a funding plan for K-LTCI benefit payment and investigating the effects of any possible revision in the K-LTCI grading system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1091-1096
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• 2004

It is necessary to consider the stability, economic environmental-friendly problems by the development of the road, supply of the automobile, environmental problem as designing the exhaust system. To reduce the noise and the vibration of the automobile. The need for stricter regulation limits emission and demand for lower fuel comsumption. According to motor vehicle company develop variable type muffler, dual muffler and active intelligence exhaust system unit. Improvement in engine performance and fuel consumption for demand information of pressure fraction and heat characteristics. To be able to determine these factor for we experiment on each case of exhaust system unit. In this study, in order to establish the optimized conditions design factors which are taking many performance as the variable valve, it shows how the standard performance and the additional element of the exhaust system effects on the engine performance.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.10
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• pp.63-73
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• 2018

As the life cycle of buildings is expected to increase, new constructions will decrease and the proportion of remodeling and repair will increase. Therefore, there is an increasing need for overall performance management of old buildings. In 2020, the proportion of buildings over 30 years old is expected to reach a half. As a result, the demand for securing and improving the performance in the stage of using the building is increasing due to the change in the demand for the building, such as the decrease in the construction permit and the increase in the use of the existing building. From this perspective, the study sought to consider institutional measures to organize the preventive and conservative maintenance of buildings. For this purpose, the conceptual goals of inspection for building maintenance were set through a literature review, and the status and problems associated with building maintenance were analyzed to suggest ways to improve the inspection system for building maintenance.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05b
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• pp.77-79
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• 2011

As residents and building owners demand maintenance that is required to achieve sustainable building performance, efficient building management methods are required. Even though the demand for maintenance systems is increasing, current maintenance work for high-rise buildings mostly uses conventional ropes and gondolas that pose a high risk of accidents and exhibit poor performance and efficiency. Thus, there is an urgent need to develop an automation robot system that can reduce accidents and improve the maintenance efficiency of the conventional high-rise building façade maintenance system. As a preceding work for the development of an automation robot system, this study classified and analyzed the work processes of actual construction sites and proposed basic techniques for the work mechanisms of the robot system by investigating the motions of cleaning workers.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.4
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• pp.227-233
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• 2019

The study examines how business conditions, demand conditions and the role of government can influence the development of batik clusters in Pekalongan. This research is expected to be able to provide recommendations for both employers and local governments in order to help in optimizing the development of batik clusters. The research applied a quantitative research by engaging multiple regression analysis as an effort to understand the effect of the relationship between independent and dependent variables. In addition, this research was conducted in three largest batik clusters in Pekalongan, Indonesia namely batik cluster of Pasindon, Kauman, and Jenggot. These results indicate that business conditions positively affect the batik clusters development. It implies that the greater both business conditions in a cluster will lead the better the development. Indeed, the demand conditions also have an impact on the cluster development. This finding remarked that demand conditions are variable that need to be considered to development of batik cluster. Lastly, Government's role is confirmed that positively related to the Development of Batik Clusters. It implies that the more active the government's role in a cluster will have a good impact on the development of the cluster in certain area.

• Korean Journal of Occupational Health Nursing
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• v.21 no.2
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• pp.87-97
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• 2012

Purpose: This study was to examine the relationship between recovery experience and the burnout among hospital nurses. Methods: A cross-sectional survey design was used. The participants were 281 nurses working at three general hospitals located in Seoul and Gyeonggi Province. The data were collected by convenience sampling using self-reported questionnaires that consisted of general characteristics, burnout, recovery experiences, self-efficacy, social support, job demand and organizational system. The data were analyzed with descriptive statistics, t-test, ANOVA, correlation, and stepwise multiple regression. Results: Stepwise multiple regression showed that organizational system had the greatest impact on hospital nurses' burnout, followed by job demand, self efficacy, position and recovery experience. Conclusion: Recovery experience is found to be a new factor that influences the burnout among hospital nurses. Therefore, further research is needed for confirming that recovery experience influences the burnout of hospital nurses. Also there is a need to develop a program to increase recovery experience from job stress at the organizational level to reduce hospital nurses' burnout.