• Journal for History of Mathematics
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• v.23 no.3
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• pp.1-20
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• 2010

Hong Jung Ha(洪正夏, 1684~?) is the greatest mathematician in Chosun dynasty and wrote a mathematics book Gu Il Jib(九一集) which excels in the area of theory of equations including Gou Gu Shu. The purpose of this paper is to find his influence on the history of Chosun mathematics. He belongs to ChungIn(中人) class and works only in HoJo(戶曹) and hence his contact to other mathematicians is limited. Investigating his colleagues and kinship relations including the affinity and consanguinity, we conclude that he gave a great influence to those people and find that three great ChungIn mathematicans Gyung Sun Jing(慶善徵, 1684~?), Hong Jung Ha and Lee Sang Hyuk(李尙爀, 1810~?) are all related through marriage.

• Journal of the Korean Society for Nondestructive Testing
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• v.29 no.4
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• pp.344-350
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• 2009

The goal of this study is to introduce the theoretical background of acoustic nonlinearity in surface wave and to verify its characteristics by experiments. It has been known by theory that the nonlinear parameter of surface wave is proportional to the ratio of $2^{nd}$ harmonic amplitude and the power of primary component in the propagated surface wave, as like as in bulk waves. In this paper, in order to verify this characteristics we constructed a measurement system using contact angle beam transducers and measured the nonlinear parameter of surface wave in an Aluminum 6061 alloy block specimen while changing the distance of wave propagation and the input amplitude. We also considered the effect of frequency-dependent attenuation to the measurement of nonlinear parameter. Results showed good agreement with the theoretical expectation that the nonlinear parameter should be independent on the input amplitude and linearly dependent on the input amplitude and the $2^{nd}$ harmonic amplitude is linearly dependant on the propagation distance.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.1
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• pp.117-125
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• 2014

The temperature distribution of steady state rolling tires with detailed tread blocks is numerically predicted using the three dimensional full patterned tire model. A three dimensional periodic patterned tire model is constructed by copying 1-sector mesh in the circumferential direction. Using the static tire contact analysis, the strain cycles during one revolution are approximated with the strains at Guassian points of the elements which are sector-wise repeated within the same circular ring of elements, by neglecting the tire rolling effect. Based upon the multi-axial fatigue theory, the maximum principal strain is used to represent the combined effect of six strain components on the hysteretic loss. In the following, the deformation due to the inflation and vertical load is calculated using ABAQUS. Then heat generation rate in each element is calculated using an in-house code. Lastly, temperature distribution is calculated using ABAQUS again. Through the numerical experiments, the validity of the proposed prediction method is examined by comparing with the experiment and the temperature distribution of a patterned tire model is compared with those of the main-grooved simple tire model.

• Journal of the Korean Society for information Management
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• v.27 no.3
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• pp.241-264
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• 2010

This study aimed to construct the Library Map Information System(LMIS) based on the Wiki theory of Web 2.0. We built this system because there was no collective source of information about every library in the world. Also, this system was developed to provide a library location information service by mashing-up with the Google Map. Through this study, the metadata applied to the newly constructed system was developed by using the Delphi method. A total of 13 experts including librarians of schools, public, academic, special, and national libraries as well as LIS faculty members and researchers, were commissioned as Delphi experts. Through three rounds of a Delphi survey analysis, the addition, modification, and deletion of the initial metadata elements was accomplished, and then the library contact/location information, library information, collection information, and event information was proposed. The metadata for LMIS was organized into four sectors and then 49 elements, each assigned to a sector.

• The Journal of the Korea Contents Association
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• v.9 no.7
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• pp.241-247
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• 2009

The purpose of this study was to investigate consciousness about the disabled on dental hygiene students and search for course of dental hygiene education as oral health care with the disabled. The subjects in this study were 538 dental hygiene students from three college in Jeonnam province. For statistical analyses of collected data, the descriptive analyses and chi-square were adopted. The obtained results were as follows. Seniors showed positive attitude about the disabled and dental service of the disabled(p<0.05). The common types of contact the disabled were physical Cerebral palsy and inner disabled were rarely. The problems are difficulty in communication, short of clinical experience in dental service of the disabled, noncooperation of the disabled, short of knowledge in dental service of the disabled. To dental service of the disabled, demand as necessity of education was 87.5%, theory and practice at the same time was 68.0% in pattern of education. Finally, 49.5% of respondents observed special dental clinic to utilization pattern of dental service of the disabled.

• Journal of Korea Multimedia Society
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• v.12 no.1
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• pp.31-40
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• 2009

Call centers have become the prevalent contact points between companies and their customers. By virtue of recent advances in communication technology, the number and size of call centers have grown dramatically. As a large portion of the operating costs are related to the labor costs, efficient design and workforce staffing are crucial for the economic success of call centers. Therefore it is very important to determine the adequate number of agents. In this context, the workforce staffing level can be modeled as mathematical optimization problem using queueing theory. In this paper, we deal with an approximate analysis of an N-design call center with two finite queues and two types of reneging customers by using the state decomposition method. We also represent some numerical examples and show the impact of the system parameters on the performance measures of the call center.

• The Journal of the Korea Contents Association
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• v.15 no.9
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• pp.118-125
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• 2015

According to the children's crime risk is increased, national police agency has implemented child safety keeper system since 2009. Despite the importance of child safety keeper studies, there was no seeking of empirical research and development plan for the operation. The purpose of the study is to find ways to improve the effectiveness of the child safety keeper system. To achieve the research objectives, all the child safety keepers were surveyed by quota sampling in the 16 provincial police agency. Questionnaire analyzed by frequency analysis, t-test, Avova, multiple regression analysis. The result of analysis is the need to strengthen links with child safety keeping house, participatory setting for the patrol route, the improvement of education management and supervision, adequacy of allowance, strengthening contact with children for job success awareness.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.1-14
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• 1998

The purpose of this study is to find out how the urban landscape of Korea, especially Seoul, changed during the last half century since 1945. The modernization of Korea, which had begun in 1960's after the chaotic period caused by Korean War, influenced the rapid growth of cities and the radical changes of its structures. But the Western-minded planning theories based on rationalism and positivism was directly applied in developing our traditional cities and consequently the modern urban landscape including urban pattern, architectural style, and commercial and residential landscape revealed disharmony, discrepancy and inconsistency in skylines, streetscape and so on. The findings are summarized as follows. 1. Because the urban structure and pattern changed in undesirable manner in terms of land use and traffic circulation, cities as a whole resulted in exclusive and heterogeneous landscape, and citizens lost their identity and felt alienated. 2. Because the architectural forms of important and monumental buildings which influenced the character of streetscape were not so successful in inventing contemporary Korean Style in true sense, we still have difficulty in creating the urban landscape of originality and legibility. 3. Because from the beginning of this era almost all highrise buildings were designed by modernism-oriented western architects, the commercial landscape of central cities did not evoke a sense of place, and after the introduction of postmodernism this tendency is ore striking even in everyday ordinary streetscape. 4. The newly formed residential landscape which was mainly composed of highly dense and highrise apartment, not only evolved very overwhelming and ugly visual impact but also exposed many social problems in living condition, neighboring and face-to-face contact. In conclusion, in ordr to define the 'Koreanness' of our urban landscape, we have to struggle to combine traditional architectural heritage and native townscape with Western shape, thought and theory, no matter how difficult it may be.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.4 s.148
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• pp.512-520
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• 2006

The effects of flexibilities of supporting structures on shaft alignment are growing as ship sizes are Increasing mainly for container carrier and LNG carrier. But, most of classification societies not only do not suggest any quantitative guidelines about the flexibilities but also do not have shaft alignment design program considering the flexibility of supporting structures. A newly developed program, which is based on innovative shaft alignment technologies including nonlinear elastic multi-support bearing concept and hull deflection database approach, has S basic modules : 1)fully automated finite element generation module, 2) hull deflection database and it's mapping module on bearings, 3) squeezing and oil film pressure calculation module, 4) optimization module and 5) gap & sag calculation module. First module can generate finite element model including shafts, bearings, bearing seats, hull and engine housing without any misalignment of nodes. Hull deflection database module has built-in absolute deflection data for various ship types, sizes and loading conditions and imposes the transformed relative deflection data on shafting system. The squeezing of lining material and oil film pressures, which are relatively solved by Hertz contact theory and built-in hydrodynamic engine, can be calculated and visualized by pressure calculation module. One of the most representative capabilities is an optimization module based on both DOE and Hooke-Jeeves algorithm.

• Korean Journal of Health Education and Promotion
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• v.20 no.3
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• pp.145-170
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• 2003

The purpose of this study was to clarity the concept of health insensitivity using Hybrid model, which consists of three phases： theoretical, empirical, and analytic. In the theoretical phase, the definitions of health insensitivity were searched in korean dictionary and examples used in the websites because the concept of health insensitivity has never been studied before. Two dimensions of health insensitivity emerged out from this investigation were cognitive and behavioral. And then a working definition of health insensitivity was established. The sub-concepts and related factors of health insensitivity were identified through the extensive reviews of the literature focusing on two dimensions of cognitive and behavioral. In the empirical phase, in order to obtain description of health insensitivity, face-to-face in-depth interviews were conducted with nine persons who are not related to professional health care. Grounded theory approach was applied to analyze these qualitative data. In the final analytic phase, theoretical results and empirical results were analyzed in the integrated way and a theoretical framework of health insensitivity was established. A refined definition of health insensitivity was that decreased health risk perception in cognitive dimension and conduction of the unhealthy behaviors in behavioral dimension. Sub-concepts of decreased health risk perception were optimistic bias and decreased general fear. Sub-concepts of unhealthy behavior were doing health threatening behavior and not doing desirable health behavior. The contact of health information was a causal condition of health insensitivity. Optimistic disposition, health locus of control, and avoidance coping style were intervening conditions of health insensitivity. Three types of health insensitivity were identified： unconcern or ignorance type, optimistic bias type, and cognitive dissonance type. Finally, The implications of these findings for further research and nursing practice are discussed.