• Nuclear Engineering and Technology
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• v.30 no.3
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• pp.262-272
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• 1998

The experiences and causes of pressure tube cracking accidents in the CANDU reactors and the development of the fuel channel at AECL(Atomic Energy Canada Limited) have been described. Most of the accidents were caused by Delayed Hydride Cracking(DHC). In the cases of the Pickering units 3&4 and the Bruce unit 2, excessive residual stresses induced by an improper rolled joint process played a role in DHC. In the Pickering unit 2, cracks formed by contact between the pressure and calandria tubes due to the movement of the garter spring were the direct cause of the failure. To extend the life of a fuel channel, several R&D programs examining each component of the fuel channel have been carried out in Canada. For a pressure tube, the main concern is focused on changing the fabrication processes, e.g., increasing cold working rate, conducting intermediate annealing and adding a third element like Fe, V, and Cr to the tube material. In addition to them, chromium plating on the end fitting and increasing wall thickness at both ends of the calandria tube are considered. There has also been much interest in the improvement of fuel channel performance in our country and several development programs are currently under way.

• Journal of the Korea Safety Management & Science
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• v.14 no.3
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• pp.59-66
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• 2012

Steel industry in Korea is a key national industry that has led economic growth for a long time. And accidents occurred from a variety of causes has endlessly made as much as remarkable achievements of steel industry. It is a fact that research achievements of disaster prevention in steel industry has not been significantly, compared to production technique achievements. And the level of interest on safety management in the steel industry is conspicuously low. Although support activity for a various safety management are provided reasonably to prevent disasters occurring with subcontractors. A method capable of quantitative evaluation, applied to subcontractors in most business places are relatively rare except parent firms-leading places. This study is to make and show safety management activities to purcue in advance in conjunction with a parent firm through development of a more systematic and quantitative evaluation model for disaster prevention with steel industry subcontractors, and to contribute to disaster prevention in domestic steel industry through advanced safety management method, by applying a proposed evaluation model of safety management activities as subcontractors in steel industry.

• East Asian Journal of Business Economics (EAJBE)
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• v.7 no.3
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• pp.1-11
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• 2019

Purposes - This study discusses various aspects of familiarity with the sea and how familiarity with the sea is perceived. This study also summarizes the literature on the factors of previous researches that affect the formation or decision of national image. Research design and methodology - Sea familiarity index was derived from the results of recognition of free association with the sea, friendliness with the sea, association of the sea with life, interest to the sea, Korea's representative marine regions, and sea related emotionalism. The familiarity with the sea (ocean) perceived by foreign visitors or foreigners in the future will be helpful in deriving a comparative research. Results - This study has identified the marine tourism resources, marine ecology, and the cognitive and emotional situations consumers feel that should be developed practically. If a continuous time series research is conducted in the future through these, it will be a chance to provide a basis for consumers' dynamic awareness. Conclusions - Through this study, it is pointed out that the research utilizing the sea and ocean to form national image highly suggested an opportunity to add and utilize new variables academically. This study on the perspective of the formation of national image suggests a new approach to add and utilize new variables to future research using the sea and ocean.

• Journal of Digital Contents Society
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• v.18 no.4
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• pp.631-639
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• 2017

Development and implementation of virtual training contents has been increasing along with the emphasis on the experience and practice in engineering education. Virtual training makes repeatable sessions possible within safe learning environment which is very similar with real work place. This feature is very helpful to learners when they manipulate real machines back at work after studying with the virtual training content. The purpose of this study is to develop "Total Station and GPSS surveying" virtual training content focusing on both theory and surveying practice within various circumstances and to explore learners experience. Results show high interest, immersion, perceived learning effectiveness, and satisfaction to the content.

• Bulletin of the Korean Chemical Society
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• v.24 no.3
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• pp.279-284
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• 2003

The One Pass Method (OPM) previously presented for the identification of single input single output systems is used to estimate the parameters of a Decentralized Control System (DCS). The OPM is a linear and therefore a simple estimation method. All of the calculations are performed in one pass, and no initial parameter guess, iteration, or powerful search methods are required. These features are of interest especially when the parameters of multi input-output model are estimated. The benefits of the OPM are revealed by comparing its results against those of two recently published methods based on pulse testing. The comparison is performed using two databases from the literature. These databases include single and multi input-output process transfer functions and relevant disturbances. The closed loop responses of these processes are roughly captured by the previous methods, whereas the OPM gives much more accurate results. If the parameters of a DCS are estimated, the OPM yields the same results in multi or single structure implementation. This is a novel feature, which indicates that the OPM is a convenient and practice method for the parameter estimation of multivariable DCSs.

• International Journal of High-Rise Buildings
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• v.6 no.2
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• pp.139-147
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• 2017

Analyzing morphological evolution over a long period of time is deemed an effective way to identify problems occurring in the process of urban development, in addition to achieving a fundamental understanding of socio-cultural changes and growth rooted from the context. As far as the urban morphology is concerned, Hong Kong is characterized by its unique high-density and compact layout patterns, which have aroused the interest of a number of authors in the urban design domain. Whilst an increasing number of redevelopment projects in Hong Kong were criticized for ignoring and destroying the old urban fabric, there is a need for research to investigate the origins and changes of various urban patterns and their implications for society. By employing the theories and techniques of space syntax, this paper accordingly provides a morphological analysis based on the Wanchai District - a 'Segment-line' city, which particularly epitomizes various urban grids of Hong Kong and may have different implications for functional aspects. By axial-mapping the urban layouts of five stages of growth since 1842 and subsequently investigating their spatial and functional transformation over the past 170 years, this paper identifies a series of spatial characteristics underlying different grid patterns, as well as achieves a precise understanding of their ever changing relationship. Based on these understandings, this paper intends to provide valuable reference and guidance for upcoming spatial development in Hong Kong and other regions.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.5
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• pp.553-559
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• 2016

There has been increasing global interest in the environmental pollution problems produced by fossil fuel consumption and greenhouse gas emissions. In order to tackle these issues, new renewable energy such as solar, wind, bio gas, fuel cell and pressure retarded osmosis(PRO) have been developed extensively. Among these energy sources, PRO is one of the salinity gradient power generation methods. In PRO, energy is obtained by the osmotic pressure generated from the concentration difference between high and low concentration solutions separated by a semipermeable membrane. The development for high power density PRO membranes is imperative with the purpose of commercialization. This study investigates development of thin film composite PRO membrane and spiral wound module for high power density. Also, the influence of membrane backing layer on power density was identified, and the characteristic factors of PRO membranes was determined. Different backing layers were used to improve power density. As expected, the PRO membrane with more porous backing layer showed higher power density.

• Korean Journal of Human Ecology
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• v.21 no.6
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• pp.1059-1082
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• 2012

The purpose of this study was to analyze the trends, research methodology and findings of various researches on family resilience published in Korea over the past 13 years. A total of 93 publications related to family resilience between 1999 and June of 2012 were analyzed; 72 journal articles and 21 doctoral dissertations which had not been published in academic journals. The results are as follows; (1) There has been steady increase in the number of related researches since 1999, with a significant increase since the mid-2000s as various nontraditional families emerged and the perception of family problems began to change. (2) With regards to the methodology, the majority of the studies were empirical, using quantitative methods in both data collection and analysis. Most measurement scales employed were based on inventories developed by foreign researchers. (3) The research subjects encompass a wide range of individuals and groups from both vulnerable families and families from the general population. Additionally, some researches focused on special interest areas including program development & evaluation and scale development. Although research on family resilience has increased in quantity, there needs to be more qualitative, longitudinal and theory grounded studies on different families and individual types to better understand family resilience in depth. In addition, specific measurement scales reflecting the unique Korean family culture should be developed. Other challenges and suggestions for future research on family resilience are discussed.

• Journal of the Korean Institute of Educational Facilities
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• v.25 no.4
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• pp.3-9
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• 2018

In recent years, schools in the urban areas are also showing their interest in the integrated school and considering adapting the actual operation method. That is why decline of the school-age population is not limited to rural areas any more, and decreasing number of students in urban schools is raised as a social issue to reconsider the continuation of schools. To solve the problems of the small-scale schools in the urban area, the integrated school is being considered as an alternative. Furthermore, the newly built schools in the urban development areas are also planned as the integrated school. Accordingly, the purpose of this study is to examine the cases of integrated schools in urban area of developed countries and to analyze their architectural planning considerations in practice.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.758-762
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• 2008

As development of IT technology, Interest of Green building has been increasing rapidly. Because the construction industry is on the center of Green development, Green construction management is demanded for efficient analysis solution of building performance. BIM has a object-oriented parametric modeling technology. IT, which green building's performance management and analysis, is very useful. A green building certification is essential course in the green building construction. So this Paper suggest him based green building simulation system. The him based green building simulation system will support resonable decision making on the early construction phase.