• Journal of applied mathematics & informatics
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• v.29 no.5_6
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• pp.1193-1204
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• 2011

In the present paper we consider a differential-algebraic prey-predator model with stage structure for prey and harvesting of predator species. Stability and instability of the equilibrium points are discussed and it is observed that the model exhibits a singular induced bifurcation when the economic profit is zero. It indicates that the zero economic profit brings impulse, i.e. rapid expansion of the population and the system collapses. For the purpose of stabilizing the system around the positive equilibrium, a state feedback controller is designed. Finally, numerical simulations are given to show the consistency with theoretical analysis.

• Korean System Dynamics Review
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• v.14 no.1
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• pp.5-29
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• 2013

This study tries to measure the direct and indirect effects of the Regional Strategic Industry (RSI) promotion projects in Chungbuk Province in Korea. In specific, it critically examines whether there exists policy consistency and connectivity between the hardware-oriented Stage I (2002~2007) and the software-centered Stage II (2008~2012) RSI promotion projects. Applying System Dynamics (SD) techniques, this study examines complex system characteristics of RSI promotion projects, all of which have been derived from the causal and stock-flow models and their simulated results. Major findings are as follows: Firstly, 'the continuous investment' is regarded as the most crucial policy leverage for the strategic industry promotion and regional economic growth. Secondly, without exceptions, the RSI promotion projects should switch their evaluation criteria to performance-oriented ones. Thirdly, in selecting their subprojects, the RSI promotion projects should pay due attention to evaluating technology value and marketability. Fourthly, it should put policy priority in strengthening cluster networking and interconnectivity among projects, inevitably supporting a selective number of virtuous network systems. Fifthly, auxiliary projects such as marketing, technology aid, and knowledge-based services should not be overlooked.

• Environmental and Resource Economics Review
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• v.10 no.1
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• pp.95-126
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• 2001

Functional values for wastewater treatment and atmospheric regulation in coastal wetland and rice paddy ecosystems are quantified, and an illustration is given on how to integrate biophysical parameters into a valuation framework. This is one of most controversial issues in economic analysis for wetland preservation versus wetland conversion to agricultural use. This paper includes theoretical considerations for estimating functional values of environmental ecosystems, and the integration of biophysical data and replacement cost method employed. Specific physical and geographical characteristics and data on ecosystem functions and services in coastal wetlands and rice paddies are addressed for evaluating their values in economic terms. In particular this paper indicates double counting problems and overestimation in the previous studies, and demonstrates how to avoid them and to maintain the consistency of valuation process involving a least-cost method, thus enables an accurate integration of the coastal wetland ecology and wetland economics. As a result which is far away from the previous studies, the total economic present value of wastewater assimilation by coastal wetland is estimated at 7,484,640 won/ha, and the net present value of positive effect for atmospheric regulation, negative effects for air pollution and water pollution by rice paddy is estimated at -37,934 won/ha, assuming that resources are infinitely long-lived and the annual value and the rate of discount (10%) is constant every year. In conclusion, for further reliability and validity of functional values for natural resources it is very noteworthy that a general equilibrium framework that could directly incorporate the interdependence between ecosystem functions and services would be preferred to the partial equilibrium framework.

• Journal of Distribution Science
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• v.20 no.3
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• pp.95-106
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• 2022

Purpose: This study aims to verify the effects of omnichannel characteristics on pleasure, resistance and repurchase intention in the omnichannel situation in order to provide the innovative commercial business. Research design, data and methodology: The study examined relations between research concepts centered on previous studies, set hypotheses, developed a research model, and verified the model through a questionnaire survey. A total of 297 questionnaires were used for the final analysis, excluding the questionnaires showing insincere or outliers. Results: First, Omnichannel showed multi-dimensional characteristics consisting of consistency, innovation, economy, and integration. Second, innovation and economic feasibility had a positive effect on pleasure. Third, only economic feasibility had a negative effect on user resistance. Fourth, consumers' shopping pleasure had a negative effect on user resistance. Fifth, repurchase intention of consumers was positively affected by innovation. Conclusions: This research contributed to extend academic framework of distribution research by examining causal relationship through adoption of economic and innovation factors as new characteristics from the integrated perspective beyond the research frame of the existing omnichannel distribution environment. Companies should provide meaningful experiences by resolving concerns about side effects caused by human-computer interaction and providing smart information that matches the products most suitable for consumer needs.

• Journal of Korea Society of Industrial Information Systems
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• v.28 no.5
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• pp.89-108
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• 2023

This study provides a comprehensive analysis of recent studies conducted on the topic of nowcasting in order to enhance the accuracy and promptness of official statistical data. Furthermore, we propose an alternative approach involving the utilization of real-time data and its corresponding collection methods to effectively operate a real-time nowcasting model capable of accurately capturing the current economic condition. We explore high-frequency real-time data that can predict economic indicators in both the public and private sectors and propose a pipeline for data collection processing and modeling that is based on cloud platforms. Furthermore we validate the essential elements required for the implementation of real-time nowcasting, as well as their data management protocols to ensure the reliability and consistency needed for accurate forecasting of official statistical indicators.

• Journal of National Security and Military Science
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• s.3
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• pp.121-167
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• 2005

The great strategy of China has been changing depending on the time, change of surrounding environment and personality of leaders of the time. However, the process of the change was not the drastic change but has maintained the consistency through the course of modification and development. The great strategy of Mao Ze-dong was to have the objective in 'World Great Nation' with the facilitation of the 'Surpass Strategy' and 'Autonomy, Independence and Alliance strategy' to successfully build up the political great nation, but he entrapped China's politics and economy into the point of no return by excessive war preparation under 'The Principle of Inevitable World War', striving of rapid communism and other policies. The Deng Xiao-ping era also targeted for ‘World Great Nation’ but, unlike Mao Ze-dong, he had the foundation in the 'The Principle of Evitable World War' and undertook the ‘Peace and Development Strategy’ and ‘Peaceful Coexistence' to build up the advantageous surrounding environment for China to focus on the economic construction as the core of the nation by establishing ‘The Reform and Opening Strategy’ and 'Three-step Development Strategy‘ to have the successful soft landing of the Chinese economy with the astonishing economic development. The system of leader's group of China after Deng Xiao-ping succeeded the practical and realistic spirit of Deng Xia-ping, and based on the drastically grown economic strength, the great strategy of China is on the ‘The Great Reinvigoration of Chinese Nation’. This is one step further from the strategy of 'World Great Nation' of the past that it embraces all the minority races in China, Chinese economic sphere, foreign citizens of Chinese origin as well as Chinese residing abroad. China contemplates the time of making 'The Great Reinvigoration of Chinese Nation’ in 2050, 100 anniversary of the birth of new China.

• Journal of Korea Port Economic Association
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• v.37 no.2
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• pp.119-131
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• 2021

Energy is an essential element in economic activity and people's lives, an important resource used by various industries, and the financialization of commodity markets has led to the growing importance of crude oil turning into the same asset as other assets. Accordingly, studies analyzing the correlation between energy prices and investor sentiment explain that investor sentiment affects oil prices through economic factors and speculation. In this study, we wanted to analyze whether the impact of the most representative changes in oil prices affects investor decision making, affecting investor sentiment, and applying wavelet consistency analysis to determine how energy prices relate to investor sentiment. Studies show that policies should be focused on policy and market changes because energy prices differ by time scale and investment sentiment should be more influential in the long term than in the short term.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.5
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• pp.175-185
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• 2019

Despite the rapid growth and importance of social enterprises in recent years, most social enterprises have many limitations such as small business size, financial dependence on government, lack of professional management personnel and knowledge, and low consumer awareness. Therefore, empirical research in the field of marketing is needed for economic independence of social enterprises. This study is based on the following: First, the identity of the social enterprise and the self-image of the consumer, second, the functional correspondence between the consumer's expectation and actual performance of the social enterprise's product, and third, the social value of the social enterprise product, the purpose of this study was to examine the effects of consumer value consistency on customer satisfaction and loyalty to social enterprises. Finally, this study aimed to suggest the moderating role of social enterprise clubs in this process to give implications for the long-term marketing of social enterprises. The results of this study are as follows. First, self-image consistency, functional correspondence, and value correspondence all have positive effects on the satisfaction of social enterprise and its products and form a loyalty. Secondly, whether or not the social enterprise club belonged to them is a moderating variable that raises sensitivity in the effects of self image consistency and functional consistency on customer satisfaction and customer satisfaction on loyalty. It was found to be.

• Journal of Preventive Medicine and Public Health
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• v.41 no.2
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• pp.74-79
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• 2008

Since the positive listing system for prescription drug reimbursement has been introduced in Korea, the number of pharmacoeconomic evaluation studies has increased. However it is not clear if the quality of pharmacoeconomic evaluation study has improved. Due to the lack of randomized clinical studies in Korean health care setting, Korean economic evaluation studies have typically integrated the local cost data and foreign clinical data. Therefore methodological issues can be raised in regard to data coherence and consistency. But the quality of data was not questiened and the potential bias has not been investigated yet. Even though changes in policy have encouraged the undertaking of pharmacoeconomic evaluations, there is few public-side funding for validation study of cost-effectiveness models and data. Several companies perform economic evaluation studies to be submitted on behalf of their own products, but do not want the study results to be disclosed to the academic community or public. To improve the present conduct of pharmacoeconomic evaluations in Korea, various funding sources need to be developed, and, like other multidisciplinary areas, the experts in different fields of study should collaborate to ensure the validity and credibility of pharmacoeconomic evaluations.

• Communications for Statistical Applications and Methods
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• v.22 no.1
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• pp.15-18
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• 2015

Reunification, (considered a 'bonanza'), is often expected to bring economic and social benefits as well as solutions to the population aging problem; consequently, the study on the population structure of North Korea is salient. This paper reviews and talks on the North Korean population and implications. In view of reliability and consistency, the North Korean population appears at an explicit change compared to the past, and shows significant differences from the South, implying that it needs significant resources to integrate during reunification. Therefore, it is opportune to discuss the North Korean population prior to the clamor for the reunification.