• Journal of Applied Reliability
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• v.16 no.4
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• pp.280-286
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• 2016

Purpose: Recently, Jiang defines the tradeoff B life to minimize a sum of life lost by preventive maintenance (PM) and corrective maintenance (CM) contribution parts and sets up an optimal replacement age of age replacement policy as this tradeoff life. In this paper, Jiang's model only considering the known lifetime distribution is extended by assigning different weights to two parts of PM and CM in order to reflect the practical maintenance situations in application. Methods: The new age replacement model is formulated and the meaning of a weight factor is expressed with the implied cost of failure under asymptotic expected cost model and also discussed with one-cycle expected cost criterion. Results: The proposed model is applied to Weibull and lognormal lifetime distributions and optimum PM replacement ages are derived with corresponding implied cost of failure. Conclusion: The new age replacement policy to escape the estimation of cost of failure in classical asymptotic expected cost criterion based on the renewal process is provided.

• 한국디지털정책학회:학술대회논문집
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• 2004.05a
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• pp.119-136
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• 2004

Business of various form such as industry, education, medium is appearing by supply of Internet of all the world. The Information Technology market is developing by leaps and bounds among them, but suitable school information education disgrace and improvement plan were not readied in domestic Information Technology and communication situation. Therefore, this proposal wishes to satisfy purpose by school information education improvement plan and manpower practical conditions about ERP education. So that, is used to accelerate medium and small enterprises information through qualitative, quantitative valuation of medium and small enterprises information manpower supply and demand as well as domestic school information.

• Journal of Industrial Technology
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• v.24 no.A
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• pp.47-57
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• 2004

Industrial efforts for increased market sales have directed towards the development and implementation of on-line marketing systems under recent e-business environment. Internet-based shopping mall is one of the most popular system. A business process model for an intermediary type shopping mall using IDEF0 has been presented in this study. Specific efforts have been focused on defining and analyzing a diversity of business processes embedded in practical B2B and B2C mall system operations. We first briefly examined the considered system with IDEF0 design. We then defined fundamental business processes within shopping mall systems. Upon careful examination and analysis of them, a detailed business process model based on IDEF methodology has been designed. The results in this study may well form a conceptual framework for shopping mall development and operations.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.4
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• pp.2254-2275
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• 2017

In this paper, we present an IND-CCA2 secure certificateless proxy re-encryption scheme in the random oracle model. A certificateless public key cryptography simplifies the certificate management in a traditional public key infrastructure and the built-in key escrow feature in an identity-based public key cryptography. Our scheme shares the merits of certificateless public key encryption cryptosystems and proxy re-encryption cryptosystems. Our certificateless proxy re-encryption scheme has several practical and useful properties - namely, multi-use, unidirectionality, non-interactivity, non-transitivity and so on. The security of our scheme bases on the standard bilinear Diffie-Hellman and the decisional Bilinear Diffie-Hellman assumptions.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.431-439
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• 2007

Data logger is generally needed for gathering field information automatically(or manually), using various sensors. However it, currently used in the county, is produced and developed by overseas. It is difficult to upgrade related program due to developed system and limited user in terms of environment it is used. On the other hand, several companies developed and sold unique data logger based their technique expertise in the country. But enhancement and practical use of related technology has much difficulties because feasibility, marketability and demand for technique are uncertain. In this study, it is the main purpose to offer basic information to select equipment suitable for field characteristic through analysis and comparison with features about method of information collection, operating program and process technique data logger which is used primarily in geotechnical engineering in both domestic and international.

• Journal of Families and Better Life
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• v.35 no.1
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• pp.59-69
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• 2017

The purpose of the study was to investigate the roles of child group home directors and their experiences with children. The study utilised the interpretive science paradigm and individual in-depth interviews for data collection. The qualitative theme analysis method explored the experiences of child group home directors. The participants, seven group home directors in the metropolitan area of Seoul, explained their multiple roles such as protector, nurturer, discipliner, mediator, and supporter of children while recognizing dysfunctions of children's family of origin. Participants claimed that the specialization of the child group home and the professionalism of its staffs were needed in order to improve the quality of child welfare. The results of this study might contribute to practical suggestions for group home professionals.

• Culinary science and hospitality research
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• v.12 no.3 s.30
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• pp.75-90
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• 2006

The purpose of this study is to understand how to activate field training internships through former researches related to training internships. The concept of field training is the same as education of work experience. Students have experienced the skills of practical jobs in the tourism industry and could enhance acquisition of professional theories. According to domestic former researches, students who participated in hotel field practice hardly satisfied with internships due to unreasonable duties, burdens and circumstances regardless of efficiency of school curriculum. Also, they showed dissatisfaction with compensation. However, foreign studies have only focused on communication between hotels and schools. Finally, in order to activate industrial field training internships, schools and hotels have more delicate harmonization to address training internship problems. In addition, promoting field training internships must include proper incentives and must be supported by school. And also the hotel management must offer incentives to the students who are under field training internships in the hotel. From internship programs, students could get much more benefits in hotel job application.

• International Journal of Ocean System Engineering
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• v.1 no.2
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• pp.68-75
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• 2011

This paper addresses an underwater landmark for updating UUV positioning information. A method is proposed in which the landmark's cubic shape and edge are recognized. The reliability, installation load, and management of landmark design were taken into consideration in order to assess practical applications of the landmark. Landmark recognition was based on topological features. The straight line recognition confirmed the landmark's location and enabled an UUV to accurately estimated its underwater position with respect to the landmark. An efficient recognition method is proposed, which provides real-time processing with limited UUV computing power. An underwater experiment was conducted in order to evaluate the proposed method's reliability and accuracy.

• Journal of Information Technology Applications and Management
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• v.12 no.1
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• pp.21-34
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• 2005

Object-oriented paradigm has required the fundamental changes in the developers' practice and orientation. However. the relevant literature has not still provided the solid practical methodology but created some myths regarding Use Case modeling. In this study. we attempt to 'demythologize' some key aspects of Use Case Modeling by describing what we have observed in our research and practice. In order to identify the developers' perceptions. the survey methodology was utilized. By discussing the differences between what must be done and what has been done. this study provides rich insights into the better understanding of the Use Case modeling and the successful development of object-oriented systems.

• Journal of Information Technology Applications and Management
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• v.10 no.2
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• pp.33-41
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• 2003

It is not easy to find desired information in the world wide web. In this research, we introduce a notion of concept network that is useful in finding information if it is used in search engines that are specialized in domains such as medicine, law or engineering. The concept network that we propose is a network in which nodes represent significant concepts in the domain, and links represent relationships between the concepts. We may use the concept network constructor as a preprocessor to speci-alized search engines. When user enters a target word to find information, our system generates and displays a concept network in which nodes are con-cepts that are closely related with the target word. By reviewing the network, user may confirm that the target word is properly selected for his intention, otherwise he may replace the target word with better ones discovered in the network. In this research, we propose a detailed method to construct concept net-work, implemented a prototypical system that constructs concept networks, and illustrate its usefulness by demonstrating a practical case.