• IE interfaces
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• v.21 no.3
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• pp.254-261
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• 2008

Connected-(r,s)-out of-(m,n) : F system is an important topic in redundancy design of the complex system reliability and it's maintenance policy. Previous studies applied Monte Carlo simulation and genetic, simulated annealing algorithms to tackle the difficulty of maintenance policy problem. These algorithms suggested most suitable maintenance cycle to optimize maintenance pattern of connected-(r,s)-out of-(m,n) : F system. However, genetic algorithm is required long execution time relatively and simulated annealing has improved computational time but rather poor solutions. In this paper, we propose the ant colony optimization approach for connected-(r,s)-out of-(m,n) : F system that determines maintenance cycle and minimum unit cost. Computational results prove that ant colony optimization algorithm is superior to genetic algorithm, simulated annealing and tabu search in both execution time and quality of solution.

• The Journal of Information Systems
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• v.24 no.3
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• pp.155-169
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• 2015

While information technology(IT) users' behaviors has been considered one of the most important research topics and studied in very many ways, 'non-use' has not been focused as a research topic. However, understanding non-use provides new insights for analyzing and understanding the essential nature of IT uses with wider frames and more qualitative dimension. The objective of this study is to provide some guidelines for studying non-use. For this purpose, the previous studies for non-use were reviewed focusing on resistance, suggested potential research issues and some research methodologies based on grounded theory.

• Journal of the Korean Society for information Management
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• v.14 no.2
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• pp.123-141
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• 1997

This study examined the extent to which variations in relevance assessments affect the evaluation of the performance of full-text retrieval system. Four sets of relevance judgments obtained by examining the full-text of documents were used to test the retrieval effectiveness. There was no noticeable difference in retrieval performance among the four relevance judgment sets. It implies that a variety of definitions of relevance has no effect on the evaluation of the performance of the full-text retrieval system. Furth r retrieval experiments on this topic incorporating relevance feedback, which is one of the sophisticated retrieval techniques using relevance information, are suggested.

• Journal of Engineering Education Research
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• v.18 no.3
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• pp.39-45
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• 2015

Many methods have been suggested for a creative problem solving approach. TRIZ approach is ranked top in its practical application because it is originated from the real patent analysis. This approach is assumed to be generic which can be applied to any types of problems regardless of problem type and its domain. The objective of this study is to propose a creative problem solving approach using TRIZ's contradiction analysis, then introduce a case study of applying this approach to a creative design coursework. Main topic covers a creative problem solving approach, a problem definition using TRIZ contradiction analysis, finding invention principles, and problem solving from the generic approach. For the course project, Roborobo tool is adopted to implement the design concept. This coursework helps students finding a general problem solving approach, and applying a generic solution for their specific problem domain.

• Journal of Engineering Education Research
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• v.13 no.2
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• pp.16-21
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• 2010

The objective of this study was to evaluate Environmental microbiology (EM) as a basic course for the environmental engineering program of Korea Maritime University which has been accredited by Accreditation Board for Engineering Education of Korea (ABEEK). Evaluation result of the lecture objectives was more than the average (3.5/5.0). The overall score for learning achievement assessment was more than average level of learning achievement (3.4/5.0). Interestingly, engineering design implementation regarding a specific topic as an extensive learning process has proven to be more effective (3.5/5.0). Some of effective class improvement strategies suggested were to encourage students to participate in the class with self-motivation and accountability: preview and review of the lecture, team presentation in English-speaking settings, and submitting project report written in English. In the future class of EM, test and evaluation of application capability of EM and environmental biotechnology (EB) theories to engineering problem solving should be emphasized.

• Journal of the Semiconductor & Display Technology
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• v.15 no.2
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• pp.16-19
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• 2016

More efficient use of the battery pack is dependent upon how to measure the remaining capacity of the battery accurately. Among various measurement methods, the basic correction measurement method has still been a hot research topic area to reduce the errors. In this paper, the problems of the existing methods have been investigated and the research direction for measuring more accurate remaining capacity has been suggested by applying the numerical simulations in the future.

• Journal of the Korea Safety Management & Science
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• v.9 no.1
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• pp.1-8
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• 2007

To improve the practical application of the thermal expansion of closed long pipeline exposing to external heating sources such as solar energy, safety engineering and system optimization for relief valve in the closed piping system are suggested through theoretical approach, correlation in view of temperature and pressure increase caused by external solar energy in the closed piping system. The profile for thermal relief valve including relieving capacity, influx heat energy, sizing criteria, set pressure, selection against back pressure is also presented. It is noted that following topic on solar relief valve should be applied to engineering, installation and commissioning.

• Journal of the Korea Safety Management & Science
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• v.8 no.4
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• pp.39-51
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• 2006

Based on the practical process engineering design and commissioning and startup operation experiences focused on chemical process safety, the comprehensive review of engineering design and installation of the thermal relief valve with its surrounding facility in a chemical plant piping system is provided to enhance the better understanding of the piping system of characteristics of thermal relief valve which is comprised of the theoretical approach, correlation in terms of temperature and pressure increase caused by external heat supply in a piping system, consideration of thermal relief valve engineering design, pressure relieving system of serial thermal relief valves and exception of their installation. It is earnestly suggested that following topic should be implemented during thermal relief valve engineering design, installation and normal operation as well.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.757-759
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• 2015

I use a common educational spectrographic device (SV2100R) in order to obtain astronomical spectra after inventing a new adaptor for telescopes. Experimental classes and learning projects in schools and public outreach are well established regarding imaging and photometry observations. However, experiments using astronomical spectrographs are rather hard to find because the procedures of spectral extraction and wavelength calibration is less convenient. SV2100R is a 1D CCD array and thus has the advantage of not requiring spectral extraction. In addition, basic wavelength calibration is preformed by the the provided software. It was adapted to a 12-inch reflecting telescope in the Korea Science Academy of KAIST in Busan and a spectrum of the bright object, Arcturus, was successfully obtained. This means one can provide educational programs on the topic of astronomical spectra. A few suggested projects are presented.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.12
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• pp.852-857
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• 2012

Recently, the indoor air pollution by microbes such as fungi and mites have become a concern as important research topic on indoor air quality. Fungal growth is significantly affected by humidity. In this study, we examined the influence of relative humidity on the surface of building materials and the water content of building materials on the fungal growth rate by measuring the mycelium length of fungi in the fungal detector placed on the surface of building materials. As a result, even if the relative humidity on the surface of building materials is identical, the more water content of building materials is, the more fungi grow faster. It was suggested that fungal growth rate depends on not only the relative humidity on the surface of building materials but also the water content of building materials.