• KOREAN JOURNAL OF CROP SCIENCE
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• v.7 no.1
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• pp.129-132
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• 1969

The polygenic variation in flowering time of soybean irradiated with Co$^{60}$ gamma ray evaluated in the R$_2$ generation. The genetic variance in the irradiation treatment was about four times that of the control. The basic possibility of selection for the early and the late in flowering time of soybean after irradiated with Co$^{60}$ was suggested in this paper.

• Journal of Korean Society for Quality Management
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• v.51 no.4
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• pp.663-675
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• 2023

Purpose: Skewness is an indicator used to measure the asymmetry of data distribution. In the past, product quality was judged only by mean and variance, but in modern management and manufacturing environments, various factors and volatility must be considered. Therefore, skewness helps accurately understand the shape of data distribution and identify outliers or problems, and skewness can be utilized from this new perspective. Therefore, we would like to propose a statistical quality control method using skewness. Methods: In order to generate data with the same mean and variance but different skewness, data was generated using normal distribution and gamma distribution. Using Minitab 18, we created 20 sets of 1,000 random data of normal distribution and gamma distribution. Using this data, it was proven that the process state can be sensitively identified by using skewness. Results: As a result of the analysis of this study, if the skewness is within ± 0.2, there is no difference in judgment from management based on the probability of errors that can be made in the management state as discussed in quality control. However, if the skewness exceeds ±0.2, the control chart considering only the standard deviation determines that it is in control, but it can be seen that the data is out of control. Conclusion: By using skewness in process management, the ability to evaluate data quality is improved and the ability to detect abnormal signals is excellent. By using this, process improvement and process non-sub-stitutability issues can be quickly identified and improved.

• Nuclear Engineering and Technology
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• v.52 no.10
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• pp.2250-2261
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• 2020

Accurate localization of radioactive materials is crucial in homeland security and radiological emergencies. Coded-aperture gamma camera is an interesting solution for such applications and can be developed into portable real-time imaging devices. However, traditional reconstruction methods cannot effectively deal with signal-independent noise, thereby hindering low-noise real-time imaging. In this study, a novel reconstruction method with excellent noise-suppression capability based on a multi-layer perceptron (MLP) is proposed. A coded-aperture gamma camera based on pixel detector and coded-aperture mask was constructed, and the process of radioactive source imaging was simulated. Results showed that the MLP method performs better in noise suppression than the traditional correlation analysis method. When the Co-57 source with an activity of 1 MBq was at 289 different positions within the field of view which correspond to 289 different pixels in the reconstructed image, the average contrast-to-noise ratio (CNR) obtained by the MLP method was 21.82, whereas that obtained by the correlation analysis method was 5.85. The variance in CNR of the MLP method is larger than that of correlation analysis, which means the MLP method has some instability in certain conditions.

• International Journal of Contents
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• v.3 no.1
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• pp.1-8
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• 2007

The distributions of the minimum correlated F-variable arises in many applied statistical problems including simultaneous analysis of variance (SANOVA), equality of variance, selection and ranking populations, and reliability analysis. In this paper, negative binomial sampling technique is employed to derive the distributions of the minimum of chi-square variables and hence the distributions of the minimum correlated F-variables. The work presented in this paper is divided in two parts. The first part is devoted to develop some combinatorial identities arised from the negative binomial sampling. These identities are constructed and justified to serve important purpose, when we deal with these distributions or their characteristics. Other important results including cumulants and moments of these distributions are also given in somewhat simple forms. Second, the distributions of minimum, chisquare variable and hence the distribution of the minimum correlated F-variables are then derived within the negative binomial sampling framework. Although, multinomial theory applied to order statistics and standard transformation techniques can be used to derive these distributions, the negative binomial sampling approach provides more information regarding the nature of the relationship between the sampling vehicle and the probability distributions of these functions of chi-square variables. We also provide an algorithm to compute the percentage points of the distributions. The computation methods we adopted are exact and no interpolations are involved.

• The Journal of Korean Medicine
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• v.25 no.1
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• pp.172-187
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• 2004

Objectives : To characterize four types of obesity and to effectively improve the treatment of obesity through Oriental medicine Methods : At 00 Oriental Medical Center, 203 female subjects who intented to lose weight were requested to complete a questionnaire. These participants were also given physical tests. The Questionnaire consisted of questions both about general life style and obesity in oriental medicine framework. The physical tests were blood tests, a body composition via Inbody 2.0, and physical strength tests. One-way analysis of variance was done to compare the means of items and physical tests between four types of obesity. Duncan was used by post hoc test. Results : 1. Significant differences between obesity type III and obesity type IV in ever tried to lose weight, childhood obesity and excercise times were observed in the questionnaire of general life style(p<0.05). 2. Ducan test showed significant differences between four obesity types in diseases (p<0.05). 3. Significant differences between four obesity types in height, % body fat muscular endurance, soft lean mass, fat mass, Trigliceride, Total cholesterol and ${\gamma}-GTP$ were observed (p<0.05). Conclusions : Further clinical research is necessary in the four types of obesity explored. The diagnosis and treatment based on these types should be further studied.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.4
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• pp.200-204
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• 2006

Purpose: Determination of pulmonary to systemic blood flow ratio (QP/QS) is important for the management of patients with left-to-right shunt. This study was performed to assess the agreement of Qp/Qs ratio using the radionuclide method and oxymetry, to investigate the factors influencing the agreement, and to know how interchangeable the results of each technique. Materials and Methods: We compared the Qp/Qs measured by single-pass radionuclide angiocardiography and oxymetry during catheterization in 207 patients who underwent both studies. In radionuclide method, Qp/Qs was calculated from the pulmonary time-activity curves using a gamma variate fit. The correlation and Bland-Altman analysis were performed according to the levels of shunt and associated lesions. Results: The mean Qp/Qs was $1.83{\pm}0.50$ by radionuclide, and $1.74{\pm}0.51$ by oxymetry. The overall correlation coefficient was 0.86(p<0.001), and Bland-Altman range of agreement encompassing 4SD was 1.05. For atrial septal defect, ventricular septal defect, patent ductus arteriosus, tricuspid and mitral insufficiency, the correlation coefficient was 0.78, 0.90, 0.84, 0.63 and 0.44, and Bland-Altman range was 1.51, 0.74, 0.96, 1.57, and 1.50, respectively. Conclusion: There is good agreement but wide variance between the Qp/Qs ratios by radionuclide method and oxymetry. Associated atrioventricular valvar insufficiency decreases the correlation coefficient and widens the variance. Wide overall variance suggests that Qp/Qs measurements by two techniques should not be used interchangeably.

• Research in Community and Public Health Nursing
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• v.30 no.3
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• pp.345-356
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• 2019

Purpose: The purpose of this study is to construct and test a structural equation model of posttraumatic growth (PTG) of earthquake victims based on Tedeschi and Calhoun's model (2004). Methods: Data were collected from 195 earthquake victims living in K. City. The exogenous variables include distress perception, resilience, and social support, and the endogenous variables include intrusive rumination, deliberate rumination, and posttraumatic growth. For data analysis, descriptive statistics, factor analysis, and structural equation modeling were performed. Results: The modified model showed a good fitness to the data. Moreover, 6 of the 9 paths of the final model were statistically significant, which include PTG affected by deliberate rumination (${\beta}=.58$, p<.001), resilience (${\gamma}=.18$, p=.001), and distress perception (${\gamma}=.20$, p=.002). These predictors explain 51.8% of variance in posttraumatic growth. Conclusion: Based on the results of this study, it is necessary to develop and disseminate preventive intervention programs to increase the resilience of earthquake-prone communities. In addition, after exposure to a community-scale traumatic event such as earthquake, we should provide social supports to alleviate distress perception and transition from intrusive rumination to deliberate rumination so that we can seek new meaning from the earthquake and facilitate posttraumatic growth.

• Economic and Environmental Geology
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• v.35 no.6
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• pp.545-552
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• 2002

In order to investigate the influence of nuclear power plant operation on its nearby environment, soil, stream and marine sediment samples were collected in the vicinity of the Youngkwang Nuclear Power Plant in Korea, and analyzed for artificial and natural radionuclide radioactivity. From the analytical result, Cs-137 was detected in most soil samples. but it may have been derived fiom past nuclear weapon tests because Cs-134 having short half-live was not detected. The radioactivities of Cs-137 in the sediment samples were also detected which are within the normal range in the sediments based upon the published literature between 1997 and 1999. For the quality control of radioactivity analysis of environmental samples, sets of marine sediments in the Gamami area were analyzed using two HPGe Gamma-ray Spectroscopes (30% and 45%) according to the geostatistical sampling strategy, and Cs-137 and K-40 results were interpreted by analysis of variance (ANOVA). In the two-way ANOVA, variances derived from the geochemical variation were significant, but errors from sampling and analytical procedures are negligible. In conclusion. all the radioanalytical procedures of this study including sampling are validated to be acceptable.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.277-286
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• 2017

This study assesses the association of nurses' hope, grateful disposition, and workplace spirituality with the goals of providing human resource management plans that lead to efficient and competitive nurse structure by building a nurse organizational culture based on analyzing the influences affecting organizational citizenship behavior. Participants were 147 nurses working in four general hospitals in Seoul and Gyeonggi-do. The survey data were analyzed by frequencies, t-test, ANOVA, Pearson correlation coefficients and multiple stepwise regression via SPSS WIN 18.0. Results showed that organizational citizenship behavior is positively associated with nurse's hope (${\gamma}=.22{\sim}.36$, p<.001), grateful disposition (${\gamma}=.38$, p<.001) and workplace spirituality (${\gamma}=.38{\sim}.54$, p<.001). The significant predictors of organizational citizenship behavior were workplace spirituality (${\beta}=.54$, p<.001), hope of turnover (${\beta}=.12$, p<.001), hope (${\beta}=.09$, p<.001) and grateful disposition (${\beta}=.08$, p<.001), which explained 41.6% of the variance in organizational citizenship behavior. This study systematizes a theory for workplace spirituality processing the early stage research in nurse structure. To improve organizational citizenship behavior among nurses, educational programs and supporting systems should be developed to increase nurses' hope, disposition of grateful disposition, and workplace spirituality.

• Journal of Environmental Health Sciences
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• v.39 no.3
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• pp.256-267
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• 2013

Objectives: The purpose of this study was to evaluate food hygiene and safety knowledge, attitudes, and practices (KAP) among the elementary school children, and furthermore, to explain the interrelations among these three variables. A second purpose was to compare gender differences of KAP. Methods: A self-administered, structured questionnaire was designed and completed by 376 elementary school children. A five-point Likert scale with twenty questions was used to gather information. Data was analyzed by frequency analysis, Pearson's correlation and analysis of variance or Student's t-test. Results: Children generally had good knowledge of food hygiene and safety, and knowledge of children was superior to the attitudes and also to their practices (p < 0.05). The attitude score was mediated between knowledge and practice scores. Significant differences (p < 0.05) were found between boys and girls in an item of knowledge, three items of attitudes, and six items of practices. A significant positive correlations were observed between knowledge and practices (${\gamma}$ = 0.70, p < 0.001), and between attitudes and practices (${\gamma}$ = 0.45, p < 0.001), as well as between attitudes and practices (${\gamma}$ = 0.51, p < 0.001), revealing that increased knowledge and even attitudes toward food hygiene safety could result in positive change in practices or behaviors. Conclusions: The results of this study indicate that despite good knowledge and attitudes of children, their practices toward food hygiene and safety are not acceptable. Gender differences in practices were highlighted. In order to create effective educational interventions on the food hygiene and safety of children, a better understanding of their awareness and the required related information is necessary.