• Structural Engineering and Mechanics
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• 제38권1호
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• pp.125-140
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• 2011

This study presents an innovative method to estimate the reliability sensitivity based on the low-discrepancy sampling which is a new technique for structural reliability analysis. Two advantages are contributed to the method: one is that, by developing a general importance sampling procedure for reliability sensitivity analysis, the partial derivative of the failure probability with respect to the distribution parameter can be directly obtained with typically insignificant additional computations on the basis of structural reliability analysis; and the other is that, by combining various low-discrepancy sequences with the above importance sampling procedure, the proposed method is far more efficient than that based on the classical Monte Carlo method in estimating reliability sensitivity, especially for problems of small failure probability or problems that require a large number of costly finite element analyses. Examples involving both numerical and structural problems illustrate the application and effectiveness of the method developed, which indicate that the proposed method can provide accurate and computationally efficient estimates of reliability sensitivity.

• JSTS:Journal of Semiconductor Technology and Science
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• 제15권1호
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• pp.101-113
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• 2015

The Monte-Carlo (MC) technique is very efficient solution for statistical problem. Various MC methods can easily be applied to statistical circuit performance analysis. Recently, as the number of process parameters and their impact, has increasingly affected circuit performance, a sufficient sample size is required in order to consider high dimensionality, profound nonlinearity, and stringent accuracy requirements. Also, it is important to identify the performance of circuit as soon as possible. In this paper, Fast MC method is proposed for efficient analysis of circuit performance. The proposed method analyzes performance using enhanced-precision Latin Hypercube Sampling Monte Carlo (LHSMC). To increase the accuracy of the analysis, we calculate the effective dimension for the low discrepancy value on critical parameters. This will guarantee a robust input vector for the critical parameters. Using a 90nm process parameter and OP-AMP, we verified the accuracy and reliability of the proposed method in comparison with the standard MC, LHS and Quasi Monte Carlo (QMC).

• 한국태양에너지학회 논문집
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• 제29권2호
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• pp.70-75
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• 2009

In this experiment, we did sampling 6 kinds of photovoltaic modules and analyzed the discrepancy of measurement results between l laboratory and 4 PV makers to have performance repeatability at Standard Test Condition(STC) condition. From the KIER's results, Korea's standard test laboratory, other laboratory showed -10% measurement variation. The causes came from correction of reference cell, test condition and the state of skill. Form the comparison test, we analyzed the problems. But three PV maker reduced measurement variation, other one PV maker and one test laboratory didn't improve the problems of correction of reference cell, test condition and the state of skill. Also, High Efficiency Module had a big discrepancy of -10.0$\sim$-6.2% among 3 laboratories which have a less than 10msec light pulse duration time. This made low spectrum response speed so the Fill Factor decreased maximum output power under 10msec light pulse duration time

• 환경영향평가
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• 제19권4호
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• pp.421-429
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• 2010

The reliability of the measurement of ambient trace species is an important issue, especially, in background area such as Gosan in Jeju Island. In a previous episodic study, it was suggested that the PM10 measurement result by the gravimetric method(GMM) was not in agreement with the result by the ${\beta}$-ray absorption method(BAM). In this study, a systematic comparison was carried out for the data between 2001 and 2008 at Gosan(GMM and BAM) and Jeju city (BAM) which is near to Gosan. It was found that at Gosan the PM10 concentration by BAM was higher than GMM and the correlation between them was low. The BAM results at Gosan and Jeju city showed similar trend implying the discrepancy at Gosan was not caused by instrumental problem of the BAM at Gosan. Based on the previous studies two probable reasons for the discrepancy are identified; (1) negative measurement error by the evaporation of volatile ambient species at the filter in GMM such as nitrate and ammonium and (2) positive error by the absorption of water vapor during measurement in BAM. There was no heater at the inlet of BAM at Gosan during the sampling period. Based on the size-segregated measurement data, it was identified that the evaporation error was minor, if any. The relationship between the two methods did not vary with the ambient relative humidity. Thus, at present, it is not clear why the discrepancy had been occurring and when using the PM10 data at Gosan, one should be aware the possible errors.

• 아동학회지
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• 제1권
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• pp.28-39
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• 1980

I. OBJECTIVES The aim of this study lies in examining following items: 1. Difference in creativity between boys and girls 2. Inter correlation of the sub-variables of creativity 3. Correlation between parent-child relationship and creativity 4. The relationship between creativity and number of siblings 5. Creativity and birth-order II. METHODS & PROCED URES 1. Instruments: Standardized Creativity Test and Parent-Child Relationship Test for children 2. Objects: 118 boys and 97 girls enrolled in primary schools in Seoul who were selected by random sampling 3. Procedure: (1) The data of the boy group and the girl group were analized by means of M,t, SD. (2)The relationships between creativity and the number of siblings as well as the relationship between creativity and birth order were analyzed by M. (3) Inter-correlations among the sub-factors of creativity were obtained in boys and girls. (4) Complex-correlations between creativity and parent child relationship were produced. III. RESULTS 1. There were no significant differences between boy and girl in creativity. 2. Inter correlation among the sub-factors of creativity Boy: The highest scores were obtained in fluidity, and adaptability, the lowest in originality and openness. Girl: The highest score were obtained in world scribbling and fluidity, the comparatively low were in originality and a match-problem. 3. Inter-correlation between creativity and parent-child relationship a. Father-son: The positive refusal type has the most significant relation and conflict type, discrepancy type, negative type in turn have significant inter-coorelations. b. Mother-son: Discrepancy type, conflict type, positive refusal type have high correlations, while negative refusal type, anticipation type, and anxiety show significance in 5% level. c. Father-daughter: Positive refusal type shows correlation of 5% level significance, while indulgence type shows negative correlation in 1% level significance. d. Mother-daughter: Discrepancy type shows 5% level significance, while indulgence type shows negative correlation in 1% level. 4. Concerning the number of siblings, it was found that, boys and girls alike, those grown among 3 or 5 showed most creativity. 5. Concerning the birth order, it was found that, boys and girls alike, the first child showed the most creativity, and the youngest showed the next to the most, while the middle showed the least creativity.

• 농업과학연구
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• 제42권3호
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• pp.237-244
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• 2015

Four ruminally cannulated Holstein steers (BW $401.0{\pm}2.22kg$) fed TMR containing low protein (CP 9.63 %) as a basal diet were used to investigate the effects of cornell net carbohydrates and protein system (CNCPS) fraction enriched protein feeds on rumen fermentation and blood metabolites. The steers used in a $4{\times}4$ Latin square design consumed TMR only (control), TMR with rapeseed meal (AB1), TMR with soybean meal (B2) and TMR with perilla meal (B3C), respectively. The protein feeds were substituted for 30 % crude protein of TMR intake. For measuring ruminal pH, ammonia-N and volatile fatty acids (VFA), ruminal digesta was sampled through ruminal cannula at 1 h-interval after the afternoon feeding. Blood was sampled via the jugular vein after the ruminal digesta sampling. Different CNCPS fraction-enriched proteins did not affect (p>0.05) ruminal pH except B3C being numerically low compared with the other groups. Ammonia-N and VFA were not significantly different among the experimental groups. Numerically low ammonia-N appeared in the steers fed rapeseed meal even though it contained high soluble N composition (A and B1 fractions). The discrepancy is unclear; however this may be related to low protein level in the diet and/or low DM intake. Blood metabolites were not significantly affected by the protein substitution except for blood urea nitrogen that was significantly (p<0.05) increased.

• Journal of Gastric Cancer
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• 제10권4호
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• pp.175-181
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• 2010

Purpose: There is controversy over the treatment for low grade dysplasia, while resection is recommended for high grade dysplasia. But the concordance of the grade of dysplasia between pre- and post-resection is low because of sampling errors with endoscopic biopsy. We attempted to establish a clearer direction for the treatment of dysplasia by clarifying the discrepancy between the pre- and postresection diagnoses. Materials and Methods: We performed a retrospective review of 126 patients who had undergone resection with the diagnosis of dysplasia on biopsy at Bundang CHA Hospital from 1999 to 2009. Results: Seventy patients were diagnosed with low grade dysplasia and 56 patients were diagnosed with high grade dysplasia. Among the 33 patients who received gastrectomy with lymph node dissec-tion, 30 patients were revealed to have invasive cancers and 4 patients showed lymph node metastasis. Discordance between the diagnoses from biopsy and resection occurred in 55 patients (44%). There was no correlation on the comparative analysis between the size, location or gross type of lesion and the grade of dysplasia. Conclusions: The rate of discordance between the diagnoses of endoscopic biopsy and the post resection pathologic report was as high as 44%. Endoscopic mucosal resection was not sufficient for some patients who were diagnosed with dysplasia on biopsy due to the presence of lymph node metastasis. It is necessary to be prudent when determining the follow-up and treatment based solely on the result of the biopsy.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제16권1호
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• pp.34-40
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• 2013

Purpose: We investigated the positivity rate and the time period to the positive color change of the urease test in children and adults and assessed the correlation of the urease test to histopathologic findings. Methods: From 1995 to 2000, endoscopic biopsies of the antrum and body were collected from 811 children and 224 adults and subjected to urease tests and histopathology. Results: The positivity rate of the urease test was 49.4% for 0-4 years, 48.4% for 5-9 years, 47.3% for 10-15 years, and 62.5% for 20-29 years in the antrum. The positivity rate was 85.1% in 0-4 years, 82.3% in 5-9 years, 74.7% in 10-15 years, and 74.1% in 20-29 years for the body. In the antrum, the highest positivity rate was <1 hour for the group aged 10-29 years and 6-24 hours in the group <10 years old (p<0.0001). In the body, the highest positivity rate was <1 hour in adults and 6-24 hours in children (p<0.0001). The proportions of the positive reactions within 1 hour were similar for the antrum and the body. In the cases of more severe chronic gastritis, active gastritis, and Helicobacter pylori infiltration, a positive urease test reaction occurred more quickly (p<0.0001). Conclusion: There were significant differences in urease tests according to age and sampling site. The discrepancy between the antrum and the body was greater in younger children. These results might be related to the low density and patchy distribution of bacteria in children and in the body.

• 동서간호학연구지
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• 제7권1호
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• pp.68-81
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• 2002

The purpose of this study is to analyze the type of ego states and stress coping style on female college students who are in the course of nursing study. This study is performed in the view of Transactional Analysis and designed to scrutinize descriptive correlations between the type of ego states and stress coping style. The subject is consists of 144 freshmen and sophomore, 138 junior and senior students group, who are students of K nursing college located in Seoul. The sampling investigation period is on Sept. 14, 2002 to Oct. 26, 2002. The measuring instrument used for Transactional Analysis ego state is 50 items Ego-gram research paper devised by Dusay(1997). For studying coping style, Folkman & Lazarus's measurement(1984) was adopted, which is translated and modified by Han, and Oh,(1990). Health states is adopted by standardized health inspecting instrumental table (Cornell Medical Index:CMI) which is designed for Korean people by Ko and Park(1980) Statistic average and standard deviation were generated by using SPSS PC+, t=test and Pearson correlation. The results were as follows: 1) In the type of ego states on both groups indicated the arithmetic apex NP(maximum value), then the point A was high and the data made a down slope to point AC. In the comparison to type of ego states between two groups, only at point CP, the data value of upper year students represented higher than that of lower year ones by c(t=2.28, p=.023). 2) Stress coping style of whole students were highly and affirmatively dedicated to research. Especially hopeful aspect(t=.67, p=.05), relaxation of tension(t=-2.16, p=.03) made significant difference each other in the view of arithmetic calculation. 3) In view of nursing students' physical health states, there is significant difference in past history(t=2.50, p=.013) and in case of mental health states, there are considerable discrepancies between lower group(73.52) and upper group(75.11)(p<.05). In view of all field, state of tension(t=2.13, p=.048) has difference. 4) While verifying coping style in terms of ego states level between lower and upper students group, In type CP, high level ego states group indicated significant difference on stress coping style area than low leveled group and made such sequences as the central point of problem, In type NP, sequences such as the central point of problem, In type A, the central point of problem, In type FC, hopeful aspect and In type AC, hopeful aspect and indifference were derived significantly different (p<.05). 5) While verifying health state differences in the level of lower and upper ego states, In type FC, low level group(150.29) marked higher point than upper group(145.19), there is remarkable discrepancy and so did whole health state(p=.014), In type AC both mental state(p=.000) and whole health state (p=.015) showed differences. 6) When analyzing correlations between whole students' ego states, copying style and health state, all type of ego state showed differences(p<.001). In correlations between ego state and health state, in type FC physical state had an apex and there are inverse correlations among the other types. Especially, type FC showed inverse correlations with great discrepancies(p<.05). In mental state, type NP(${\gamma}=.198$, p<.001) and type A(${\gamma}=.166$, p<.05) represented straight correlations with remarkable differences. Especially, In type AC showed inverse correlations(${\gamma}=.282$, p<.001). In case of correlations between copying style and health state, indifference(${\gamma}=-.157$) and relaxation of tension(${\gamma}=-.158$) presented great difference(p<.05). In mental state, central point of problem and search for social support showed straight correlations with great discrepancies(p<.05), hopeful aspect and indifference showed inverse correlations with considerable differences(p<.001).