• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.6
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• pp.331-338
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• 1988

A simple algorithm is presented for solving the thermal unit commitment problem which is one of very important areas in economic operation of power systems. This algorithm is based on simple priority ordering by the unit operation cost and it is shown that the operation cost of chosen sets of generators is the minimum. The proposed method differs from the conventional priority-based formulations in that the unit operation are calculated in every load level. Further the poerating reserve requiements are satisfied by the newly derived analytical security function or the expectation of reserve. The proposed method is proven to be very simple, accurate and efficient in a sample system.

• Journal of Labour Economics
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• v.33 no.3
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• pp.25-46
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• 2010

The outstanding performance of some nations in Central and Northern Europe such as Denmark and the Netherlands in the labor market is much indebted to their policy to help labor flexicurity. In this study, the possibility of replicating the Dutch or Danish performance in the labor market is explored in case of adopting such policy in the 22 OECD countries. If implementing the flexicurity policy in the 22 member countries of the OECD leads to strong performance in the labor market, this policy can be globally shared as universal labor policy to provide a win-win situation among the labor, management and the authorities on the matter, paving the way for replacing the Anglo-Saxon policy characterized by high flexibility and low security, or the European alternative with a lower level of flexibility and a higher level of security. According to findings from our research, flexicurity policy can not produce any tangible accomplishments in the labor market by only itself. Therefore, we may safely reach the conclusion that flexicurity policy has a limited positive influence on the labor market of some northern or central European countries. Given the striking difference in inherent conditions between such European countries and OECD countries, it is not sensible for OECD nations to adopt labor policy in the direction of flexicurity.

• Journal of the Korea Convergence Society
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• v.9 no.7
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• pp.69-75
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• 2018

The key technology of Industry 4.0, Smart factory is evaluated as the driving force of our economic development hereafter and a lot of researches have been established. Various entities including devices, products and managers exist in smart factory, but roles of these entities may be continuous or variable and can become extinct not long after. Existing methods for access control are not suitable to adapt to the variable environment. If we don't consider certain security level, important industrial data can be the targets of attacks. We need a new access control method satisfying desired level of efficiency and security without excessive system loads. In this paper, we propose a new RBAC-PAC which extend AC defined for PKC to the authority attribute of roles. We distribute PACs for roles through block chain method to provide the efficient access control. We verified that RBAC-PAC is more efficient in the smart factory with large number of entities which need a frequent permission update.

• Communications for Statistical Applications and Methods
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• v.22 no.1
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• pp.31-40
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• 2015

This study proposes a mathematical model that can forecast national defense expenditures. The ongoing European debt crisis weighs heavily on markets; consequently, government spending in many countries will be constrained. However, a forecasting model to predict military spending is acutely needed for South Korea because security threats still exist and the estimation of military spending at a reasonable level is closely related to economic growth. This study establishes two models: an Auto-Regressive Moving Average model (ARIMA) based on past military expenditures and Transfer Function model with the Gross Domestic Product (GDP), exchange rate and consumer price index as input time series. The proposed models use defense spending data as of 2012 to create defense expenditure forecasts up to 2025.

• The Southeast Asian review
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• v.20 no.2
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• pp.135-178
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• 2010

This study is to seek alternatives for regional governance related to transnational labor migration issues in Southeast Asia. This study examined the present situation and trends of labor migration in the region, reviewed involved transnational issues, and identified the current issues of governance to seek alternatives for regional governance. The increase in cross-border labor migration is no doubt a sign of growth and dynamism of the region and greater integration of their economies. But it also poses complex policy and management issues as well as transnational issues over such as unequal economic profits, illegal migration, human rights, and social security issues. In this reality, regional governance is a very important theme and the efforts to manage their migration inherently involve fundamental conflict and tension between related countries and regions. However, politics and governance of transnational migrant workers in Southeast Asia are still pursued at the national level. To resolve these issues, it is urgently required to secure not only collaboration between the parties concerned but also governance at the regional level. Findings of this study are: First, although labor migration has been a relatively long-time transnational issue, the history of addressing the issue at the regional governance is very short and still inceptive. Second, given its size, labor migration in Southeast Asia requires effective regional governance but no breakthrough was possible due to the conflict of interests between origin and destination countries and the conflict of logic between the labor market and the state. Third, the issue of labor migration is an important element for the formation of economic and socio-cultural communities the ASEAN countries have pursued. Fourth, it is urgently needed to seek alternatives for good and effective regional governance as a key to resolving these issues over migrant workers in Southeast Asia.

• Food Science and Preservation
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• v.10 no.3
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• pp.376-380
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• 2003

This aims is to estimate the consumers' preference on the brand rice using factor analysis, completed research on the consumption of brand rice revealed that the household supply in the Seoul area is increasing. An analysis whether housewives' preference in chosing the brand of rice was developed through the consumption experience and re-purchase intention investigation for the brand rice. Also the paper analyzed the consumers' preference using the logit and probit model. Number of respondents who participated in the study(95 ％) totaled 1000 and the sampling method utilized was the multistage stratification and assignment abstraction. Results showed that the preference of housewives' depends on age, education and level of income. Such that as age, education, income level increase so thus their preference for brand rices also increase. Also the re-purchasing of brand rice is high when housewives have a higher educational attainment and prefers to go to work. Conclusively, the long-term sale view for brand rice is closely related to the economic conditions of a household. Hence, with the economic growth, there is a possibility that consumption of brand rice would increase compared to the ordinary rice. We can propose the following political intent from analysis of these results. First, There is a need for continuous public information as reinforcement for brand rice. Second, Marketing operation reinforcement could also be done for customer class security etc.

• Electronics and Telecommunications Trends
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• v.38 no.4
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• pp.12-24
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• 2023

The acquisition of advanced scientific and technological knowledge is essential for the economic and security interests of any nation. Major countries are actively accumulating capacities by strategically identifying and nurturing key technologies, aiming to gain a competitive advantage amidst internal and external environmental shifts and the global competition for technological dominance. By comparing and analyzing trends in strategic technology policies in leading countries, we may be able to understand Korea's technology status and level as well as identify technologies to focus or develop. Accordingly, this study scrutinizes policy trends, criteria for technology selection, objectives, and strategies adopted by major countries regarding strategic technologies and offers insights into Korea's technological development by means of comparative analyses across strategic technologies among these countries.

• 한국노년학
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• v.27 no.2
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• pp.427-443
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• 2007

The purpose of this study is to find out how work participation of the elderly and their general characteristics - socio-demographic, economic, and health traits - influence on their self-esteem. The data was collected through one on one interviews of 295 elderly. Data on general attributes and the discrepancies in the level of self-esteem between work participants and non-participants were analyzed by using t-test and ANOVA, while the effects of work participation on their self-esteem were analyzed by multiple regression analysis. Results of this study shows us that work participation is the strongest predictor that determine the level of self-esteem for the elderly. In other words, work participation can make the aged better off and give them a sense of security and satisfaction. Finally, these findings may be used for realizing us the importance of the work participation program and developing and designing new promising approaches of work participation program, which meet psychological needs of the elderly as well as their economic needs.

• Journal of the Korea Fashion and Costume Design Association
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• v.19 no.1
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• pp.107-120
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• 2017

The purpose of this study was to investigate the effects of fashion shopping orientation and mobile shopping characteristics on consumer's perceived value. In addition, mobile purchase experiences of male consumers in their 20s~30s were analyzed. Questionnaires were carried out from November 10, 2015 to November 20, 2015 and 230 useful data were analyzed by descriptive statistics, exploratory factor analysis, reliability analysis, ANOVA, duncan test, multiple regression using Spss 21. The results of this study were as follows: First, fashion shopping orientation of male consumers was composed of five factors, which were 'brand ostentatious orientation', 'pleasure/trend orientation', 'economic orientation', 'impulse orientation' and 'time-saving orientation'. Second, mobile shopping characteristics were divided into three factors including 'ease of use', 'personalization', and 'security'. Third, fashion shopping orientation factors such as 'pleasure/trend orientation', 'economic orientation', and 'time-saving orientation' had a significant influence on the perceived value, while all the factors of mobile shopping characteristics affected the perceived value significantly. Fourth, there were significant differences among the classsified groups based on the level of purchase frequency and the period of using mobile shopping mall in fashion shopping orientation factors. Fourth, there were significant differences among the group classified by the level of purchase frequency in mobile shopping characteristics factors. These results suggested the differenciated strategies for customer management to make male consumers lead to mobile purchase.

• International Journal of Computer Science & Network Security
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• v.21 no.11
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• pp.301-311
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• 2021

The technological advancements of the last two decades directed the era of the Internet of Things (IoT). IoT enables billions of devices to connect through the internet and share their information and resources on a global level. These devices can be anything, from smartphones to embedded sensors. The main purpose of IoT is to make devices capable of achieving the desired goal with minimal to no human intervention. Although it hascome as a social and economic blessing, it still brought forward many security risks. This paper focuses on providing a survey of the most commonly used application layer protocols in the IoT domain, namely, Constrained Application Protocol (CoAP), Message Queuing Telemetry Transport (MQTT), Advanced Message Queuing Protocol (AMQP), and Extensible Messaging and Presence Protocol (XMPP). MQTT, AMQP, and XMPP use TCP for device-to-device communication, while CoAP utilizes UDP to achieve this purpose. MQTT and AMQP are based on a publish/subscribe model, CoAP uses the request/reply model for its structuring. In addition to this, the quality of service provision of MQTT, AMQP, and CoAP is not very high, especially when the deliverance of messages is concerned. The selection of protocols for each application is very a tedious task.This survey discusses the architectures, advantages, disadvantages, and applications of each of these protocols. The main contribution of this work is to describe each of the aforementioned application protocols in detail as well as providing their thorough comparative analysis. This survey will be helpful to the developers in selecting the protocol ideal for their system and/or application.