• Structural Engineering and Mechanics
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• v.25 no.3
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• pp.347-363
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• 2007

A novel methodology, referred to as Auxiliary Domain Method (ADM), allowing for a very efficient solution of nonlinear reliability problems is presented. The target nonlinear failure domain is first populated by samples generated with the help of a Markov Chain. Based on these samples an auxiliary failure domain (AFD), corresponding to an auxiliary reliability problem, is introduced. The criteria for selecting the AFD are discussed. The emphasis in this paper is on the selection of the auxiliary linear failure domain in the case where the original nonlinear reliability problem involves multiple objectives rather than a single objective. Each reliability objective is assumed to correspond to a particular response quantity not exceeding a corresponding threshold. Once the AFD has been specified the method proceeds with a modified subset simulation procedure where the first step involves the direct simulation of samples in the AFD, rather than standard Monte Carlo simulation as required in standard subset simulation. While the method is applicable to general nonlinear reliability problems herein the focus is on the calculation of the probability of failure of nonlinear dynamical systems subjected to Gaussian random excitations. The method is demonstrated through such a numerical example involving two reliability objectives and a very large number of random variables. It is found that ADM is very efficient and offers drastic improvements over standard subset simulation, especially when one deals with low probability failure events.

• Journal of the Korean Data and Information Science Society
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• v.28 no.3
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• pp.709-720
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• 2017

In healthcare and medical research, many important variables have a measurement error such as body mass index and laboratory data. It is also not easy to collect samples of large size because of high cost and long time required to collect the target patient satisfied with inclusion and exclusion criteria. Beside, the demand for solving a complex scientific problem has highly increased so that a semiparametric regression approach could be of substantial value solving this problem. To address the issues of measurement error, small domain and a scientific complexity, we conduct a multivariable Bayesian smoothing under structural measurement error covariate in this article. Specifically we enhance our previous model by incorporating other useful auxiliary covariates free of measurement error. For the regression spline, we use a radial basis functions with fixed knots for the measurement error covariate. We organize a fully Bayesian approach to fit the model and estimate parameters using Markov chain Monte Carlo. Simulation results represent that the method performs well. We illustrate the results using a national survey data for application.

• Journal of Forest and Environmental Science
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• v.34 no.3
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• pp.246-248
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• 2018

Urban development and population have augmented the increase of impervious land-cover. This phenomenon has amplified the effects of climate change and increasing urban island effects due to increases in urban temperatures. Seoul, South Korea is one of the largest metropolitan cities in the world. While land uses in Seoul vary, land cover patterns have not changed much (under 2%) in the past 10 years, making the city a prime target for studying the effects of land cover types on the urban temperature. This research seeks to generalize the urban temperature of Seoul through a series of statistical tests using multi-temporal remote sensing data focusing on multiple scales and typologies of green space to determine its overall effectiveness in reducing the urban heat. The distribution of LST values was reduced as the size of urban forests increased. It means that changing temperature of large-scale green-spaces is less influenced because the broad distribution could be resulted in various external variables such as slope aspect, topographic height and density of planting areas, while small-scale urban forests are more affected from that. The large-scale green spaces contributed significantly to lowering urban temperature by showing a similar mean LST value. Both of concentration and dispersal of urban forests affected the reduction of urban temperature. Therefore, the findings of this research support that creating urban forests in an urban region could reduce urban temperature regardless of the scale.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.77-85
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• 2020

The aim of this study is two-fold. Firstly, it attempts to assess the level of management accounting practices (MAPs) in manufacturing companies in Vietnam. Secondly, it purports to explore the impact of potential contingency factors on the current level of MAPs in the sample of studied companies from the industrial sector in Vietnam. The study examines the hypotheses that MAPs in Vietnamese manufacturing firms are affected by a range of contingent variables. A quantitative research was conducted by sending questionnaires to the target respondents that comprise both accountants and managers in 160 manufacturing enterprises in the north of Vietnam. The first main findings from the study reveal that MAPs in Vietnam are mainly traditional rather than contemporary ones, and oriented toward the short-term rather than the long-term. The second main research findings resulted from multiple regression model show that MAPs in Vietnam are significantly affected by company size, commitment of directors, advanced manufacturing technology, and distinct number of products. However, no significant associations are found between MAPs and intensity of competition from the emerging market as hypothesized in this study. Research findings are bases for recommendations to promote the application of contemporary practices and enhance management accounting functions in manufacturing companies in Vietnam.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.697-706
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• 2021

This quantitative study aims to examine the effect of family ownership on company performance empirically. Specifically, this study examines the moderating effect of corporate governance on the relationship between family ownership and company performance which has never been explored in the previous studies. This study's main target population was all listed companies in the Indonesian Capital Market Directory (ICMD) for 2008-2018. The study used criteria, namely data completeness, to measure research variables and obtained 2996 data or firm-year observations. The research contingency model to test the proposed hypothesis was the General Moment Method (GMM). The study presents the results of data descriptions shows the average, median, maximum, minimum, and standard deviation values for each variable. The descriptive data shows that family ownership is common in Indonesia: 64% of 244 companies in the sample. The inferential analysis results using a multiple regression model test show that family ownership significantly reduces company performance. However, corporate governance proxied by the board of directors, managerial risk profile, and independent commissioners significantly moderate the relationship between family ownership and company performance. Besides, the managerial risk profile and independent commissioners strengthened while the board of commissioners' presence weakened the effect of family ownership on performance.

• Journal of Korea Trade
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• v.26 no.1
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• pp.113-125
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• 2022

Purpose - The primary purpose of this study is to verify whether the target set out by the International Maritime Organization (IMO) for reducing carbon emissions from ships can be achieved by quantitatively analyzing the trends in technological advances of fuel oil consumption in the container shipping market. To achieve this purpose, several scenarios are designed considering various options such as eco-friendly fuels, low-speed operation, and the growth in ship size. Design/methodology - The vessel size and speed used in prior studies are utilized to estimate the fuel oil consumption of container ships and the pace of technological progress and Energy Efficiency Design Index (EEDI) regulations are added. A database of 5,260 container ships, as of 2019, is used for multiple linear regression and quantile regression analyses. Findings - The fuel oil consumption of vessels is predominantly affected by their speed, followed by their size, and the annual technological progress is estimated to be 0.57%. As the quantile increases, the influence of ship size and pace of technological progress increases, while the influence of speed and coefficient of EEDI variables decreases. Originality/value - The conservative estimation of carbon emission drawn by a quantitative analysis of the technological progress concerning the fuel efficiency of container vessels shows that it is not possible to achieve IMO targets. Therefore, innovative efforts beyond the current scope of technological progress are required.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.1
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• pp.109-117
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• 2000

The purpose of this study is to examine the effect factors in suburban rural landscape and significant factors of apartment complex which are effective to the skyline of the sloped mountains. Also it is to propose the basic resources to preserve and improve the suburban rural landscape. The target site is Young-In, which shows the typical of rural development. Sides were take in young-In City along the roads and selected for 20 pieces. This study used questionnaire about the suburban rural landscape surveying of 45 students in Kyunghee Univ.. Also we found 2 dependent variables and 8 independent variables totally. Moreover, we have analyzed the data using descriptive statistics, correlation analysis, and multiple linear regression method between the preference and physical factors, and between the vulnerability and perceptional factors. The results are as follows: 1) With the dependent variable of preference, the areas of "green space" and "agricultural productive lands" were highly influenced in the suburban rural landscape positively, but the areas of "apartment complex" and "other buildings" were negatively effected. 2) With the dependent variable vulnerability, the area "apartment complex" and cutting numbers of the "skyline of mountainous ridge" were proved as significantly positive factors, but the length of the "skyline of mountainous ridge" turned out to be a negative factor. Although this study has the difficulty to be generalized, it can be used for planning and designing of the apartment complex in suburban rural landscapes, and it will provide the basic guideline for preserving and managing of the suburban rural landscapes.uideline for preserving and managing of the suburban rural landscapes.

• Child Health Nursing Research
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• v.17 no.3
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• pp.161-166
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• 2011

Purpose: This study was done to examine body satisfaction of children, self-rated health of children and parent-child attachment as perceived by children and their mothers in relation to children's health behavior and to identify factors affecting health behavior of children. Ultimately the purpose of this study was to provide basic data to develop health promotion programs for children. Methods: Participants were 140 couples, 4th grade elementary school students and their mothers residing in Busan. Data collection was done during June 1 and July 31, 2010. The data were analyzed using paired t-test, Pearson correlation coefficients and stepwise multiple regression with PASW 18.0 program. Results: Children and mothers rated body satisfaction of the child differently. Children's responses for body satisfaction of child and parent-child attachment were associated with health behavior of children. Self-rated health perceived by children was also a factor affecting health behavior, as were body satisfaction perceived by children and mothers' perception of body satisfaction of child in that order. These variables explained 18.2% of the total variances in health behavior of children. Conclusion: The findings indicate that body satisfaction and self-rated health of children are important variables to target within intervention research and treatment programs for health promotion behavior of children at home and school.

• Journal of Preventive Medicine and Public Health
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• v.23 no.4 s.32
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• pp.404-415
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• 1990

This study was conducted to analyze the relations among nutritional knowledge, nutrional attitude, eating practice and total nutritional diagnosis and also to find the influencing factors of them. The survey was done during the period from April 1990 to June 1990 and the target population were Ewha Womans University students (freshmen and senior) of whom 1,354 peoples were surveyed. The summarized results are as follows ; 1. For the teaming environment, the percentage of completion on nutritional knowledge course was 28.6% and among them the department of foods and nutrition had the highest score(100.0%) and the next was dept. of medicine (53.4%). 2. To find the relation which the nutritional knowledge, nutritional attitude, eating practice and the total nutritional diagnosis influence on one another, the multiple correlation analysis was done. The attitude and the practice were highly correlated with total nutritional diagnosis, but the correlation between nutritional knowledge and total nutrional diagnosis was not significant. The correlation between the practice and nutritional knowledge which were positively and significantly correlated with attitude respectively was positive but not significant. 3. The difference which were analyzed by department, grade and completion on knowledge course on the nutritional knowledge, attitude, eating practice were significant (p<0.01) by ANOVA. 4. The significant variables on nutritional diagnosis are the eating practice points, the grade, the knowledge course, the breakfast and the attitude ($r^2=10.3%$) by multiple regression analysis. This study has the limitation that it did not consider the environmental factors of dietary life such as dietary culture, family environment, cultural habit. Therefore important points of these dietary studies are to extend to the practical nutritional education and dietary improvement for the national health not restricted to the local area or local population.

• Progress in Medical Physics
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• v.15 no.2
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• pp.84-93
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• 2004

Stereotactic radiosurgery (SRS) is a technique that delivers a high dose to a target legion and a low dose to a critical organ through only one or a few irradiations. For this purpose, many mathematical methods for optimization have been proposed. There are some limitations to using these methods: the long calculation time and difficulty in finding a unique solution due to different tumor shapes. In this study, many clinical target shapes were examined to find a typical pattern of tumor shapes from which some possible ideal geometrical shapes, such as spheres, cylinders, cones or a combination, are assumed to approximate real tumor shapes. Using the arrangement of multiple isocenters, optimum variables, such as isocenter positions or collimator size, were determined. A database was formed from these results. The optimization procedure consisted of the following steps: Any shape of tumor was first assumed to an ideal model through a geometry comparison algorithm, then optimum variables for ideal geometry chosen from the predetermined database, followed by a final adjustment of the optimum parameters using the real tumor shape. Although the result of applying the database to other patients was not superior to the result of optimization in each case, it can be acceptable as a plan starling point.