• Nuclear Engineering and Technology
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• v.38 no.8
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• pp.753-762
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• 2006

In this paper, works related to enhancement of the CHF are reviewed in terms of fundamental mechanisms and practical applications. Studies on CHF enhancement in forced convection are divided into two categories, CHF enhancement of internal flow in tubes and enhancement of CHF in the nuclear fuel bundle. Methods of enhancing the CHF of internal flows in tubes include enhancement of the swirl flow using twisted tapes, a helical coil, and a grooved surface; promotion of flow mixing using a hypervapotron; altering the characteristics of the heated surface using porous coatings and nano-fluids; and changing the surface tension of the fluid using additives such as surfactants. In the fuel bundle, mixing vanes or wire wrapped rods can be employed to enhance the CHF by changing the flow distributions. These methods can be applied to practical heat exchange systems such as nuclear reactors, fossil boilers, fusion reactors, etc.

• Journal of the Korean housing association
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• v.10 no.3
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• pp.153-164
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• 1999

The purpose of this study is to investigate preferences of middle-aged people for elderly housing in order to properly plan elderly housing; 1 ) To analyze the middle-aged peoples' preferences for elderly housing in each situation based on the following 4 categories; elderly couple/healthy, elderly couple/unhealthy, elderly living alone/healthy, elderly living alone/unhealthy. 2) To clarify the differences in preferences for elderly housing according to the subjects' backgrounds in each case. This research intends to understand the form of elderly housing and desire for the environment of subjects, middle-age, who will be old aged, and the change of preference to characteristics for elderly housing according to the change of situation. The data were collected through structured questionnaires. The subject were 298 middle-aged, 40-50's who will be experiencing aging, major customer of elderly housing in the future.

• IE interfaces
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• v.18 no.2
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• pp.184-192
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• 2005

In recent research there has been intense interest in understanding how real option valuation (ROV) approaches might usefully complement conventional discounted cash flow (DCF) techniques. However, investment decision makers in a real world have been worried about adopting the ROV approaches mainly because of difficulty in technically understanding the theory of the ROV approaches as indicated by many researchers. With this difficulty in mind, we propose the opportunity cost model as another discrete-time model to value a deferral option. The main advantage of observing a real options value in terms of the opportunity cost concept is to provide a technique for practitioners to estimate a wide range of real options values without sticking to a financial option modelling. The fundamental ground for developing the opportunity cost model proposed in this paper lies in the work of dissecting the structure of the real options value into three categories: capital gain, expected opportunity loss, and expected opportunity gain. At the end of the paper, we will present a short illustrative example to demonstrate the applicability of the model.

• Advances in concrete construction
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• v.10 no.6
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• pp.499-507
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• 2020

In current study, utilizing the Kelvin's theory with polynomial, exponential and trigonometric volume fraction laws for functionally graded cylindrical shell vibrations. Effects of different parameters for ratios of length- and height-to-radius and angular speed versus fundamental natural frequencies been determined for two categories of cylindrical shells with clamped-free edge condition. By increasing different value of height-to-radius ratio, the resulting backward and forward frequencies increase and frequencies decrease on increasing length-to-radius ratio. Moreover, on increasing the rotating speed, the backward frequencies increases and forward frequencies decreases. The frequencies are same when the cylinder is stationary. The frequencies increases and decreases on changing the constituent materials. The frequency results are verified with the earlier literature for the applicability of present model.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.3
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• pp.29-43
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• 2012

This study evaluated 23 botanic gardens and arboretums under two main categories including professional group and operational group. As for professional group, the main difference between the functions of botanic gardens and arboretums was analyzed. In the case of operational group compared professional group respectively, on categories including importance of function and implementation, seeking to provide fundamental data of botanic gardens and arboretums by enhancing the quality of visitors and examining functional differences. The result of a difference in arboretums' function between professional and operational groups, the study analyzed the importance of botanic gardens and arboretums in terms of detailed categories such as research, education, collection, display, retention, and service for visitors. As a result, professional group showed retention 4.32>education 4.11>research 4.09>service for visitors 4.05, and operational group showed retention 3.70>service 3.52>education 3.41>research 3.37, indicating that both groups had retention as the most selected answer. Looking closely at the functions of the currently implemented detailed categories of botanic gardens and arboretums, such as research, education, collection, display, retention, and service for visitors, the study showed that 91.3% selected rare species and individual multiplication for research function, 78.3% chose education of natural ecosystem for children for education, 73.9% answered space for experiencing nature for display, and 73.9% also replied managon, diof rare species, reproduction, and retention of native plants' species for retention category, and service for visitors showed 95.7% for implementation. The study could not clearly point out the influence between predictors due to absence of an established comprehensive evaluation model. Also, it analyzed and reviewed comparison of functions of professional group and operational group, but in the future, it should conduct study on a systemic and objective classification of botanic gardens and arboretums to clearly examine the difference in views between groups, which also requires, at the same time, study on management policy of botanic gardens and arboretums or suggesting guidelines that suit types of forms, and also study on facilities and program development that can be applied to each class.

• The Korean Nurse
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• v.35 no.2
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• pp.52-70
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• 1996

This historical research was conducted to analyze and categorize the titles which were presented in the journal, The Korean Nurse, from August 1962 to October 1995. Titles which were published with the purpose of educating graduate nurses and to update 0 their nursing knowledge to improve professional practice were included. There were 348 articles published from the beginning of publication in August, 1962 to October, 1995. All of the journals were reviewed except nine missing journals which were not available in any library. According to the characteristics of the articles in the periodical, the articles were divided into three periods. In each of the three peroids there were five categories: Subject, Clinical Practice, Fundamentals of Nursing Science, Nursing Administration, Others. These categories were adopted from Kim's(1994) division system which was developed to analyze nurse's insurance education program. The special feature peroid was from August, 1962 to December, 1974. In this period the articles were presented in an unorganized manner in the area of special feature or main issue. The largest area was the subject category(44%). The second largest area wes the fundamental of nursing science category(31%). From May, 1975 to December, 1977, the articles with the educational purposes were published in a designated area called continuing education. This period was labelled as the continuing education period. Among the published articles in this period, 45% focused on the subject category and 45% on the fundamentals of nursing science category. In this period the articles were focusing on nurses 'work in specific areas such as industry, nurses' aid schools, and nursing administration, articles on physical assessment first started to appear. The written continuing education period was from January 1978 to October, 1995. All the educational articles published in this area were analyzed and categorized into five areas as for the other periods. 48% of the articles focused on the subject category. In the mid-eighties, the term nurse specialist first.appeared and ten years later in 1990, the titles were subdivided into more specific titles, such as, home nursing, industrial nursing, emergency nursing, 23% were in the fundamental nursing science category and they dealt with nursing process, nursing theories, theory development. For the content analysis, three articles, one from each period, dealing with cardiovscular diseases were selected for comparsion. First, the special feature period, the title of the article was on diet therapy for cardiovascular disease patients, but instead the content was about rest, hygiene, medication, observation. They recommended rings to prevent bed sores, which is now considered as a cause for bed sores. In the continuing education period, the content was more focused on rehabilitation rather than general nursing .care. It became more specific, systematic, and organized compared with the special feature period. In the written continuing education period, the focus was on rehabilitation, not broadly, but very specifically on exercise. The further research on the content analysis is recommended along with a comparison of the trends in the Journal of Nurses Academic Society.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.147-159
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• 2016

This study is intended to draw a scale for problem behaviors of young children. To achieve this, an empirical survey was carried out on experts from three groups of daycare center teachers, kindergarten teachers and early childhood education-majored professors. A total of 209 items were measured by the scale for young children's problem behaviors from the 1970s to now. The results showed that 96 of a total 209 items in 5 categories related to the scale for young children's problem behaviors were adopted as major items. Using these 96 major items in 5 categories, 17 out of 40 items in a peer relationship category, 13 out of 41 items in a development category, 20 out of 50 items in a fundamental habit category, 22 out of 38 items in a morality category, and 24 out of 40 items in an emotion category were adopted. Most items were adopted in the emotion category, whereas most items were rejected in the development category. Therefore, it is judged that their problem behaviors are caused mainly by anxiety, shrinking, unexpected behaviors, dependence on parents or teachers, and slow behaviors due to the latent negative emotions of young children at the developing stage.

• The Journal of Society for e-Business Studies
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• v.8 no.4
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• pp.129-149
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• 2003

Explosive growth of mobile devices over the past years has greatly increased commercial interests in mobile commerce, but mobile commerce has not yet seen enough increase on demand side as anticipated. Despite the slow start, mobile commerce has a lot of potential from users' perspective. In order to make this potential a reality, businesses must focus on the values from their customers' perspective, not technical competencies. This research employed Keeney's(1992) value focused thinking approach and explore values of mobile commerce from actual users' viewpoint. In depth interviews were conducted with seventy Practical users of mobile commerce. Through an extensive focus group sessions, 748 statements obtained from actual users were classified into 18 categories of means objectives and 12 categories of fundamental objectives of mobile commerce. The means-ends network diagram of values seen in mobile commerce by actual users were presented and compared to typical electronic commerce diagram. Results suggest the mobile commerce needs to be handled differently from the traditional electronic commerce.

• Journal of the Korea Fashion and Costume Design Association
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• v.12 no.1
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• pp.25-34
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• 2010

Design in the 21st Century requires showing extraordinary and revolutionary possibilities by merging multiple cultures or different art forms. 21C fashion also increases its's complexity through the blending in of other design field's styles and forms. In other words, 21C's fashion design involves not only clothing, but combines techniques, aspects and functions fulled from various design categories. As a result, Current fashion design becomes more unique, and shows various styles. From this point of view, this study focuses on creating and suggesting unique textile designs through the understanding of design processes of textiles, which are inspired by high tech architectural structures. The fundamental shape of the architectural structures were simplified into thick lines and geometric shapes. these design elements were then transferred into textile designs. As a result, unique textile looks were created, and were applied to the apparel designs by CAD to see 3d simulations. Exchanging or merging ideas of different design categories leads innovative and fresh looks. 21C is rapidly changing, and designers need to continually introduce new looks every season. Incorporating 21st Century consumption patterns, designers must understand the process of creating original designs through various methods. The innovative fabric designs for this study involved a creative process of drawing from a step by step breakdown of two separate design fields, which were then merged into one finished design. The data and research from this study can be used as a reference tool for any further applicable fashion and textile designs in the future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.135-138
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• 2003

Appropriate allocation of personal and financial resources of a research organization is important for the successful accomplishment of its goals. Direct-seeding of rice is a technology compatible with sustainable agriculturer and much research on the technology has been carried out in the research institutes of Rural Development Adminstration (RDA). We analyzed, with a special interest in research on rice direct-seeding technology, patterns of resource allocation in RDA by technology to evaluate congruency levels in research resource allocation. Research on direct-seeding technology had been focused on its fundamental field in the past. However, research to solve the practical difficulties encountered by farmers such as those in seedling establishment weed control, and water management practices, has been increased in recent years. Research resource allocation had largely been made to the projects for variety and seeding-technology development in the early years, however, allocation to the projects for the fertilization, weed control, and water management fields has been increased in recent years. Allocation of resources to the projects in soil management and seedling establishment categories was decreased, indicating that difficulties encountered by farmers in these fields were mostly solved. High congruency between economic outcome of research and allocation of resources by technology categories indicates a rational allocation of resources for research on direct-seeding of vice in RDA.