• Nuclear Engineering and Technology
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• v.55 no.8
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• pp.2935-2940
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• 2023

A polystyrene phantom was developed following the guidance of the International Atomic Energy Association (IAEA) for gamma knife (GK) quality assurance. Its performance was assessed by measuring the absorbed dose rate to water and dose distributions. The phantom was made of polystyrene, which has an electron density (1.0156) similar to that of water. The phantom included one outer phantom and four inner phantoms. Two inner phantoms held PTW T31010 and Exradin A16 ion chambers. One inner phantom held a film in the XY plane of the Leksell coordinate system, and another inner phantom held a film in the YZ or ZX planes. The absorbed dose rate to water and beam profiles of the machine-specific reference (msr) field, namely, the 16 mm collimator field of a GK Perfexion^TM or Icon^TM, were measured at seven GK sites. The measured results were compared to those of an IAEA-recommended solid water (SW) phantom. The radius of the polystyrene phantom was determined to be 7.88 cm by converting the electron density of the plastic, considering a water depth of 8 g/cm². The absorbed dose rates to water measured in both phantoms differed from the treatment planning program by less than 1.1%. Before msr correction, the PTW T31010 dose rates (PTW Freiberg GmbH, New York, NY, USA) in the polystyrene phantom were 0.70 (0.29)% higher on average than those in the SW phantom. The Exradin A16 (Standard Imaging, Middleton, WI, USA) dose rates were 0.76 (0.32)% higher in the polystyrene phantom. After msr correction factors were applied, there were no statistically significant differences in the A16 dose rates measured in the two phantoms; however, the T31010 dose rates were 0.72 (0.29)% higher in the polystyrene phantom. When the full widths at half maximum and penumbras of the msr field were compared, no significant differences between the two phantoms were observed, except for the penumbra in the Y-axis. However, the difference in the penumbra was smaller than variations among different sites. A polystyrene phantom developed for gamma knife dosimetry showed dosimetric performance comparable to that of a commercial SW phantom. In addition to its cost effectiveness, the polystyrene phantom removes air space around the detector. Additional simulations of the msr correction factors of the polystyrene phantom should be performed.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.381-386
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• 2016

Background: Bladder cancer is an international public health problem. It is the ninth most common cancer and the fourteenth leading cause of death due to cancer worldwide. Given aging populations, the incidence of this cancer is rising. Information on the incidence and mortality of the disease, and their relationship with level of economic development is essential for better planning. The aim of the study was to investigate bladder cancer incidence and mortality rates, and their relationship with the the Human Development Index (HDI) in the world. Materials and Methods: Data were obtained from incidence and mortality rates presented by GLOBOCAN in 2012. Data on HDI and its components were extracted from the global bank site. The number and standardized incidence and mortality rates were reported by regions and the distribution of the disease were drawn in the world. For data analysis, the relationship between incidence and death rates, and HDI and its components was measured using correlation coefficients and SPSS software. The level of significance was set at 0.05. Results: In 2012, 429,793 bladder cancer cases and 165,084 bladder death cases occurred in the world. Five countries that had the highest age-standardized incidence were Belgium 17.5 per 100,000, Lebanon 16.6/100,000, Malta 15.8/100,000, Turkey 15.2/100,000, and Denmark 14.4/100,000. Five countries that had the highest age-standardized death rates were Turkey 6.6 per 100,000, Egypt 6.5/100,000, Iraq 6.3/100,000, Lebanon 6.3/100,000, and Mali 5.2/100,000. There was a positive linear relationship between the standardized incidence rate and HDI (r=0.653, P<0.001), so that there was a positive correlation between the standardized incidence rate with life expectancy at birth, average years of schooling, and the level of income per person of population. A positive linear relationship was also noted between the standardized mortality rate and HDI (r=0.308, P<0.001). There was a positive correlation between the standardized mortality rate with life expectancy at birth, average years of schooling, and the level of income per person of population. Conclusions: The incidence of bladder cancer in developed countries and parts of Africa was higher, while the highest mortality rate was observed in the countries of North Africa and the Middle East. The program for better treatment in developing countries to reduce mortality from the cancer and more detaiuled studies on the etiology of are essential.

• Journal of the Korean Home Economics Association
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• v.38 no.12
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• pp.131-143
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• 2000

This research aims to examine the pro-environmental food consumption behavior of two groups; the housekeepers and the restaurant cooks. The rationale for choosing these groups as target of research lies in the fact that they are expected to be the most active subject for enhancing the desirable culture of food consumption, through their close involvement in the whole process of food consumption in society. This study assumes the four areas of activity to be the meaningful categories in the investigation of the pro-environmental food consumption behaviour; planning of menu and purchasing the food materials, cooking, eating, and disposal of the leftover. By using these four categories, we attempt to provide with the empirical typology of pro-environmental food consumption behaviour and the analysis of the relations of it with socio-demographical variables. Their pro-environmental behaviors are divided into four types: $\circled1$ The positive awareness of pro-environmental cooking and eating, $\circled2$ The positive awareness of pro-environmental food consumption behavior, $\circled3$ The passive awareness of pro-environmental cooking and eating, $\circled4$ The passive awareness of pro-environmental food consumption behavior. There is no significant difference among the numbers of the cases that belong to each behavioral type. Seen in overall, however, we can say that the larger number of the cases belong to the passive type of behavior. Two socio-demographical variables of tole housekeepers and the restaurant cooks show significant corelations with the behavioral types of pro-environmental food consumption with the confidence level P<0.05, but there is no significant co-relations in other variables like gender, marital status, age, income, Engel coefficient, education. We also found that there is no great gap between the housekeepers and the restaurant cooks in their positive awareness of pro-environmental food consumption, the percentage of each group belonging to the type being 51.9% and 48.1%, respectively, but that the former shows much greater number than the latter in belonging to the passive awareness type of the pro-environmental food consumption, 75.3% and 24.7%, respectively. Although the restaurant cooks can be said to be more ego-friendly than the housekeepers, if we consider the rapidly growing trend of outgoing-diner, more efforts should be exerted to develop the education and advertisement program for enhancing the restaurant cook's pro-environmental awareness and propagating the desirable food consumption cloture.

• Korean Journal of Environment and Ecology
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• v.32 no.6
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• pp.686-697
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• 2018

Due to the advance in remote sensing technology, it has become easier to more frequently obtain high resolution imagery to detect delicate changes in an extensive area, particularly including forest which is not readily sub-classified. Time-series analysis on high resolution images requires to collect extensive amount of ground truth data. In this study, the potential of land coverage mapas ground truth data was tested in classifying high-resolution imagery. The study site was Wonju-si at Gangwon-do, South Korea, having a mix of urban and natural areas. KOMPSAT-3A imagery taken on March 2015 and land coverage map published in 2017 were used as source data. Two pixel-based classification algorithms, Support Vector Machine (SVM) and Random Forest (RF), were selected for the analysis. Forest only classification was compared with that of the whole study area except wetland. Confusion matrixes from the classification presented that overall accuracies for both the targets were higher in RF algorithm than in SVM. While the overall accuracy in the forest only analysis by RF algorithm was higher by 18.3% than SVM, in the case of the whole region analysis, the difference was relatively smaller by 5.5%. For the SVM algorithm, adding the Majority analysis process indicated a marginal improvement of about 1% than the normal SVM analysis. It was found that the RF algorithm was more effective to identify the broad-leaved forest within the forest, but for the other classes the SVM algorithm was more effective. As the two pixel-based classification algorithms were tested here, it is expected that future classification will improve the overall accuracy and the reliability by introducing a time-series analysis and an object-based algorithm. It is considered that this approach will contribute to improving a large-scale land planning by providing an effective land classification method on higher spatial and temporal scales.

• Asia Marketing Journal
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• v.15 no.4
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• pp.1-32
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• 2014

The purpose of this paper is to investigate upon a diversification strategy through market creation of CJ Group, which has contributed in positioning of the firm as one of the leading conglomerates in South Korea. With such objective, the background of CJ Group, followed by its business diversification strategies were explored, with reference to several case studies. The history of CJ Group began with establishment of CheilJedang Industrial Corporation in 1953, as the first domestic sugar producer and exporter of South Korea. The corporation gradually expanded its business ever since at both national and global level, to include the fields of food production, pharmaceutical, biotechnology, and life chemicals. Later, CheilJedang (CJ) Group was established as an affiliate of CheilJedang Industrial Corporation. With such independence, extension of business has been witnessed across the industries of media, entertainment, finance, information technology and distribution. Thus, the current CJ Group pursues to define itself as a progressive global living culture company with four major business categories from food and food service, biotechnology, entertainment and media, and logistics. Despite its success in today's market, CJ Group underwent hardships in its business diversification in 1990s due to indiscreet management, along with the Asian financial crisis. Here, many firms overcame the financial difficulties by taking advantage of the exchange rate for overseas expansion. Though, CJ Group tried to differentiate itself by focusing on the domestic market by creating something out of nothing. Hence, CJ Group takes a unique position among many cases of business diversification and their categorization. In an effort to identify and classify the types of growth experienced by the top 30 companies in South Korea, the firms were categorized into four groups according to their diversification strategies adapted after the Asian financial crisis. Based on the mode and time of entry, corporations were identified either as the 'Explorer', 'Invader', 'Venture Capitalist', or 'Assimilator'. Here, the majority of the firms showed the qualities of Invader, entering mature markets through large-scaled mergers and acquisitions. However, CJ Group was the only firm that was categorized as an Explorer, for its focus on the newly emerging service sector in culture-contents industry. This diversification strategy through market creation is worth examining, due to its contribution in generating simultaneous growth between the market and the company itself. Diverse brands of CJ Group have been referred to as case studies in this regard, from 'Hatban', 'Cine de Chef', 'VIPS' to 'CJ GLS'. These four businesses, each to represent processed food, film, restaurant service, and logistics industries respectively, show CJ Group's effectiveness in creating a whole new category of goods and services that are innovative. In fact, such businesses not only contributed in advancement of consumers' wellbeing, but toward generating additional value and employment. It is true that the diversification strategy of CJ Group requires long-term capital investment with high risk, compared to the other strategies mentioned in the paper. However, this model does create high employment and additional values that are positive to both the society and the firm itself. Therefore, the paper comes to a conclusion that the diversification strategy through market creation conveys the most positive impact relative to the others.

• Child Health Nursing Research
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• v.4 no.2
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• pp.177-192
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• 1998

The early postpartum period is crucial toward in recovery from childbirth and attainment of the maternal role. Maternal role attainment is a complex social and cognitive process of stimulus-response accomplished by learning. Helping for maternal role attainment is one of nursing goals in the early postpartum period. Based on King's conceptual framework for nursing, this study was planned as descriptive correlation study to determine the significant differences of the degree of nursery room nurses' role performance according to several variables of personal, interpersonal, and working system of nurses in nursery room. The purpose of this study was to contribute to the planning of nursing care to help maternal role attainment of the early postpartum period of mothers and to the development of relevant nursing theory. The data were collected from Feb. 3 to 28 by questionnaires with 273 nurses in nursery room. The instruments for this study were consisted of four parts : 21 questions for rot performance of nurse. 37 questions for personal system of nurse including 31 questions for role perception of nurse : 65 questions for interpersonal system including 63 questions for job stress of nurses , 18 questions for working system of nurse. The toos to measure role performance and role perception, and job stress of nurse were tested for internal reliability. Cronbach's Alphas were 0.9612, 0.9058, and 0.9649. The data were analysed by using in S.A.S. computerized program and included percentage, t-test, ANOVA Pearson Correlation Coefficient, and Duncan multiple range test. The conclusions obtained from this study are summerized as follows : 1. The mean score of the items of role performance was 2.12(SD=0.55) in Likert's 4 points scale. 2. The degree of role performance was significantly different according to role perception(p=0.0001), age (p=0.006), educational background(p=0.002) , and certificate of midwife (p=0.03) among variables of personal system of subjects. 3. The degree of role performance was significantly different according to job stress (p=0.0001) and numbers of children(p=0.006) among variables of interpersonal system of subjects. 4. The degree of role performance was significantly different according to having opportunities for baby(p=0.03), the degree of flexibility to bring baby to mother's room(p=0.046), the scope of visitor for baby(p=0.016) , the degree of flexibility of visiting for baby (p=0.049) , the degree of participation of nurse in establishing visiting rules(p=0.017), existence and/or nonexistance of rules for breast feeding(p=0.010) , existence and/or nonexistance of education for breast feeding (p=0.009), existence and/or nonexistance of breast feeding room(p=0.013) , concert methods for breast feeding (p=0.003), working place (p=0.0001), and career(p=0.019) among variables of personal system of subjects.

• Korean journal of food and cookery science
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• v.25 no.1
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• pp.74-83
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• 2009

We investigated the food service management practices in child care centers operated by various types of foundations in the Chonbuk area of Korea. Self-administered questionnaires were collected from 125 child care center directors. The statistical analysis was completed using an SPSS v11.5 program. Approximately 82.4% of the directors were women with an the average age of 45 years old. The average number of children in each public and private child care center was 84.7 and 88.8, respectively (P<.001), and the difference in time of operation was significant(P<.001). Only 20.8% of the centers employed a dietitian, whereas 92.0% of the centers employed a cook, thus, food service was not managed by professionals in most centers. In approximately 99.2% of the centers, meals were prepared in a conventional manner. The difference in daily meal frequency was significant(P<.05), with approximately 85.6% of the centers serving snacks twice a day primarily to supplement the intake of nutrients(4.44 point) and to add fun to the daily lives of the children(4.12 point). Approximately 40.7% of the directors of public centers and 57.6% of the directors of private centers responded that the most difficult aspect of food service management was financial management. Overall, 56.8% of the directors responded that the details of financial management had the greatest effect on their ability to improve the quality of food service. In most centers, the center director was also the purchasing manager and half of them purchased food every day. Approximately 97% of the directors responded that they do not include instant foods in their menu plans but they would use them if the children wanted to eat them. These results indicate that the food service management in child care centers in the Chonbuk area is relatively inadequate. We strongly recommend that they hire dietitians for food service administration and focus on strengthening sanitation management.

• Korea journal of population studies
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• v.16 no.2
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• pp.125-139
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• 1993

Korea has successfully achieved a lowered fertility level owing to the strong population control policy and effective family planning program. Along with fertility decline and decreased number of children in family, average number of household members has decreased and nontraditional households such as one person household and households composed of unrelated individuals have prolifirated, even though the absolute number of them are found minimal in Korea. However in recent years several data and survey results suggest that one person households are gradually in the increasing trend. The study aimed at investigating the real state of one person households in Korea and next analyzing the proportional distribution of one person households by a few socioeconomic characteristics, thus providing basic for eatablishing far-singhted population and social welfare policy in the future. Korea has experienced high growth rate of economy through government-led development plans starting from the 1960s. During the past three decades, Korea has shifted from the agricultural state to the industrialized one. In compliance with the economic growth, urbanization and industrialization have brought about rural-to-urban migration and a great bulk of young population migrated to urban areas, who are seeking for educational and job opportunities. Korean society has also been under drastic change in every aspect of life involving norms, tradition, and attitude, etc. Therefore, in spite of the prejudice on 'living alone' still remaining, young people gradually leave parents and home, and further form nontraditional households in urban areas. Current increase in the number of one person households is partly attributable to the increase in high female educational attainment and female participation in economic activities. As the industrial structure in Korea changes from primary into secondary and tertiary industries, job opportunities for service/sales and manufacturing are opened to young female labor force in the process of industrialization. Contrary to the formation of one person households by young people, the aged single households are composed when children in family leave one by one because of marriage, education, employment. In particular, a higher proportion of aged female single households occur in rural areas due to the mortality difference by sex. Based on the data released form the 1990 Population and Housing Census and National Fertility and Family Health Survey in 1985 and 1991, the study tried to examine the state of one person households in Korea. According to Census data, the number of one person households increased to 1, 021, 000 in 1990, comprising 9.0 percent of total households. And the survey reveal that among total 11, 540 households, 8.0 percent, 923 households, are composed of one person households. Generally, the proportion of female single households is greater than that of male ones, and a big proportion of one person households is concentrated in the 25-34 age bracket in urban areas and 65 years and more in rural areas. It is shown than one person householders in urban areas have higher educational attainment with 59.2 percent high schooling and over in 1991, Job seeking proved to be the main reason for leaving home and forming one person households. The number of young female single households with higher education and economic self-reliance are found nil and the study did not allow to analyze the causal realtionship between female education and employment and one person household formation. However more research and deep analysis on the causal facors on one person household formation using statistical method are believed to be necessary.

• Journal of Korean Home Economics Education Association
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• v.19 no.4
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• pp.153-173
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• 2007

The purpose of this study is to investigate the middle school students' allowance managing behaviors and consumer education by the educational subject in order to explore a desirable direction of consumer education for allowance management. Questionnaire survey was conducted with 468 middle school students in Gyeongnam. The major findings are as follows: First, as for recognition of consumer education, the consumer education from home was the highest, and then the from school and mass media followed in that order. Second, the average score of the students' allowance managing behavior was low. The fulfillment ability was relatively high compared to planning and evaluative ability. Third, as for overall allowance managing behaviors, the more promoted a students' level of consumer education from school and mass media, the more cultivated his/her allowance managing behaviors. As for allowance managing behaviors in accordance with sub-factors, students' planning and fulfillment abilities were more cultivated, the more promoted his/her level of consumer education from school and mass media. Students' evaluative ability was more cultivated, the more promoted his/her level of consumer education from school and mass media. Fourth, there were differences in educational contents the students wanted in accordance with the educational subjects of consumer education. The consumer education can be more practical when it is connected with home, school, and mass media, development of an educational program with such connection is necessary.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.6
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• pp.1001-1012
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• 2018

Regarding the small- and medium-sized enterprises in Korea that manufacture the railway vehicle parts, there are over 250 related companies. And they have been surviving in the form of producing and delivering the parts of the railway vehicles by importing the technologies and the products of the foreign countries rather than possessing their own technological abilities. Due to this, regarding the industry of the core components of the railroads, the dependence on the overseas has been high. As such, although, for supporting the small- and medium-sized enterprises that manufacture the railway vehicle parts, the government has been strengthening the diverse policy supports, it is a fact that the effectiveness of the support is not high. And, in order to effectively support these, there is a need to understand clearly and definitely what the important promotion factors are in the process of the technology commercialization. Accordingly, through the precedent researches regarding the factors that promote the technology commercializations of the small- and medium-sized enterprises that manufacture the railway vehicle parts, this research had extracted 10 main items. And the level of the importance of these indices was analyzed by using the AHP (Analytic Hierarchy Process). As a result of the AHP analysis, the factors within a corporation appeared to be the most important factor. And, as for the lower-ranking item, the commercialization capability was analyzed to be the most important item. It is highly expected that the contents and the results of this research will be usefully used when formulating the planning of the support program and the support policy for the technology commercializations by the public research organizations and the railroad management organization, which is an organization that supports the small- and medium-sized enterprises that manufacture the railway vehicle parts.