• International Journal of Reliability and Applications
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• 제6권1호
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• pp.31-39
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• 2005

An economic life test sampling plan for products with exponential lifetime distribution is developed. To reduce test time, a test plan with curtailed Type II censoring is considered. A cost model is constructed which involves three cost components; test cost, accept cost, and reject cost. Determination of optimal plan minimizing the expected average cost per lot is discussed with a constraint related to consumer's risk. Some numerical examples are provided.

• Journal of applied mathematics & informatics
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• 제5권1호
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• pp.263-268
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• 1998

This paper proposes the two-sample comparison us-ing sign test based on ranked-set sample(RSS). We investigate the asymptotic properties of the proposed test statistic and compare the asymptotic relative efficiencies of the proposed test statistic with re-spect to Mann-Whitney-Wilcoxon test statistic based on RSS and Mann-Whitney-Wilcoxon test statistic based on the simple random sample(SRS).

• Journal of the Korean Statistical Society
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• 제27권1호
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• pp.11-23
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• 1998

A Bayes criterion for testing the equality of covariance matrices of two multivariate normal distributions is proposed and studied. Development of the criterion invloves calculation of Bayes factor using the imaginary sample method introduced by Spiegelhalter and Smith (1982). The criterion is designed to develop a Bayesian test criterion, so that it provides an alternative test criterion to those based upon asymptotic sampling theory (such as Box's M test criterion). For the constructed criterion, numerical studies demonstrate routine application and give comparisons with the traditional test criteria.

• Journal of the Korean Statistical Society
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• 제15권1호
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• pp.26-30
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• 1986

Basu (1980) examined Fisher Randomization Test (FRT) of matched pair experimental data with critical point of view. Additionally, Lane (1980) pointed out that "the experimenter may be interested in a weaker notion of equality between two treatments, " than the notion of equality which FRT relies on. In this study, a randomization test is developed so that it can test a weaker hypothesis of equality. equality.

• 대한본초학회지
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• 제22권4호
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• pp.51-58
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• 2007

Objectives : Investigation of the memory and cognitive enhancing effect of HT008-1 in scopolamine induced amnesia mice. Methods : At 60 min before acquisition trials, HT008-1 (30, 100, 300 mg/kg p.o.) was administered, and 30 min later, mice were injected with scopolamin (1.0 mg/kg, i.p.). In the passive avoidance test, acquisition trials were carried out 30 min after a single scopolamine treatment. Retention trials were carried out 24h after acquisition trials. Y-maze test was carried out 30 min after a single scopolamine treatment. Spontaneous alternation behavior during an 8-min session was recorded. Inhibitory effects of HT008-1 (0.01, 0.1, 1.0 mg/ml) on AChE activity was measured. Result : HT008-1 ameliorated scopolamine-induced learning impairments and spatial cognitive function in passive avoidance and Y-maze test, respectively. Moreover HT008-1 showed a significant inhibitory effect on AChE activity. Discussion: This study presented that eMultiherb mixture HT008-1 enhanced learning memory and spatial cognitive function in scopolamine-induced amnesia mice. These results suggest that the effect of HT008-1 may be dependent on the inhibition of AChE activity.

• 대한임상검사과학회지
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• 제39권3호
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• pp.151-155
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• 2007

Diagnosis and prevention of cytogenetics diseases are one of the most important parts in prenatal care. For that reason, it is necessary to examine birth defects. However, there is no reliable statistical data about birth defects in our country. In this study, the ratio of birth defects were determined by cytogenetics analysis and amniocentesis, in addition, the usefulness of amniocentesis was analyzed. The screening test and the triple marker test were conducted for 3,325 pregnant women of between 15 and 22 weeks gestation. Amniocentesis was performed for 170 pregnant women who were positive in the two tests, 184 women of advanced maternal age and 48 women with family history of chromosome aberrations. Among 419 women, 8 pregnant women who were positive in the triple marker test, 1 woman who close to the cut-off value in the triple marker test, 2 women with advanced maternal age and 1 woman who has history of chromosome aberration pregnance that was positive in cytogenetics analysis. The overall incidence of chromosomal aberration was 12 cases including 7 cases of Down's syndrome, 1 case of Patau syndrome, 1 case of Klinefelter syndrome, 1 case of Edward syndrome, 1 case of Robertsonian translocation and 1 case of XYY syndrome. These results show that amniocentesis for pregnant women who need chromosome test in prenatal cytogenetics analysis is very useful.

• 한국작물학회지
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• 제19권
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• pp.7-13
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• 1975

백미의 alkali 붕괴도 청정에 필요한 최적조건을 구하기 위하여 test-tube miller를 사용하여 도정하고 25$^{\circ}$, 30$^{\circ}$, 35$^{\circ}$ 및 4$0^{\circ}C$의 온도에서, 1.4%에서 2.8%까지 8수준의 KOH 농도로 일정한 시간을 두고, Indica, Japonica등 10품종을 사용하여 alkali붕괴도 시험을 행하여, 본 정 검정에 영향을 미치는 백미의 도정 정도, KOH 농도 처리온도 및 처리시간을 점토하였다. 그 결과를 요약하면 다음과 같다. 1. Test-tube miller에서 90분간 도정한 시료는 alkali검정에 적당한 도정도를 나타내었다. 2. Japonica와 Indica를동시에 검정할 경우에는 1.8%의 KOH농도에서, Japonica만을 검정할 경우에는 1.4% 혹은 그 이하의 농도에서, 또 Indica만을 검정할 경우에는 2.2%의 농도에서 각각 3$0^{\circ}C$, 18시간 동안 처리하는 것이 최적 조건으로 보였다.

• 보건행정학회지
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• 제26권3호
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• pp.207-218
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• 2016

Background: This study was performed to identify factors associated with the utilization of tests for diabetes complication and hemoglobin A1c (HbA1c) among diabetes patients in Jeollanam-do, Korea. Methods: The study subjects were 2,310 diabetes patients participated in 2014 community health survey in Jeollanam-do, Korea. Dependent variables were the utilizations of fundus examination, microalbuminuria test, and HbA1c test. The used statistical analysis methods were chi-square test and hierarchical regression analysis with weight in consideration of complex sample design. Results: The utilization rates of fundus examination, microalbuminuria test, and HbA1c test were 25.8%, 27.4%, and 12.3%, respectively. In the results of hierarchical regression, fundus examination was significantly related to age, education level in predisposing factors, residential area in enabling factors and recognition of blood sugar, drug therapy, and subjective health status in need factors. Microalbuminuria examination was significantly related to monthly income, residential area in predisposing and health screening, recognition of blood sugar, drug therapy, diabetic education, number of chronic disease, and subjective health status in need factors. HbA1c examination was significantly related to age, education level, marital status in predisposing factors, residential area in enabling factors and drinking, recognition of blood sugar, drug therapy, and diabetic education in need factors. Conclusion: The results of this study were shown that perception of their disease seriousness, education about diabetes management, and accessibility of tests were important to utilization of test for diabetes complication and HbA1c. It might be necessary to the develop and strength strategies for enhancing the utilization of tests for diabetes complication and management in diabetes patients.

• 대한기계학회논문집A
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• 제30권9호
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• pp.1034-1040
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• 2006

Due to the need of increasing thermal efficiency, supercritical pressure and temperature have been utilized in power plants. It is well known that 9Cr1Mo steel is suitable fer use in power plants operating at supercritical conditions. Therefore, to ensure the safety and the soundness of the power plant, creep characterization of the steel is important. In this study, the creep characterization of the gCr1Mo steel using small punch creep(SP-Creep) test has been described. The applied load and the central displacement of the specimen in SP-Creep test have been converted to bearing stress and strain of uc, respectively. The converted SP-Creep curves clearly showed the typical three-stage behavior of creep. The steady-state creep rate and the rupture time of the steel logarithmically changed with the bearing stress and satisfied the Power law relationship. Furthermore, the Larson-Miller parameter of the SP-Creep test agreed with that of the tensile creep test. From the comparison with low Cr-Mo steels, the creep characteristics of 9Cr1Mo steel proved to be superior. Thus, it can be confirmed that the 9Cr1Mo steel is suitable for supercritical power plant.

• Journal of Periodontal and Implant Science
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• 제29권1호
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• pp.15-30
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• 1999

The purpose of this study was to evaluate the effect of mixed extracts of aralia cortex and phellodendron cortex (P55A) on activities of human gingival fibroblasts and periodontal ligament cells in vitro. First experiment was done to evaluate the effect of P55A in normal condition. In control group, the cells($4.5{\times}10^4$ cells/ml) were cultured with Dulbecco's Modified Eagle's Medium contained with 10% fetal bovine serum. In experimental groups, P55A was added to the above culture condition at the final concentrations of 0.1 ${\mu}g/ml$(Test group 1), 1 ${\mu}g/ml$(Test group 2) and 10 ${\mu}g/ml$(Test group 3). Then each group was tested for the cell proliferation rate at $\frac{1}{2}$, 2, 5 days, protein levels at 2, 5 days, and alkaline phosphatase activity at 2, 5 days. Second experiment was done to evaluate the effect of P55A in high glucose condition. 200 mg/dl glucose was added to the same culture condition of all groups in first experiment. Then each group was tested for the cell proliferation rate at $\frac{1}{2}$ , 2, 5 days, protein levels at 2, 5 days, and alkaline phoaphatase activity at 2, 5 days. The results were as follows ; 1. First experiment 1) As P55A concentration increased, cell proliferation rate increased significantly in test group 2 at 2 days, and test group 2 and 3 at 5 days in human gingival fibroblasts and periodontal ligament cells(P<0.05). 2) In human gingival fibroblasts, all test groups showed significantly increased protein levels as compared to control group at 5 days. In periodontal ligament cells, test group 2 and 3 showed significantly increased protein levels as compared to control group at 2, 5 days(P<0.05). 3) Alkaline phosphatase activity of human periodontal ligament cells increased as P55A concentration increased. The test group 2 and 3 showed significant increase as compared to control group at 5 days(P<0.05). 2. Second experiment 1) As P55A concentration increased, cell proliferation rate increased significantly in test group 2 at 2 days, and test group 2 and 3 at 5 days in human gingival fibroblasts and periodontal ligament cells(P<0.05). 2) In human gingival fibroblasts, test group 3 showed significantly increased protein levels as compared to control group at 2 days, and all test groups at 5 days. In periodontal ligament cells, test group 2 and 3 showed significantly increased protein levels as compared to control group at 2, 5 days(P<0.05). 3) Alkaline phosphatase activity of human periodontal ligament cells increased as P55A concentration increased. The test group 2 and 3 showed significant increase as compared to control group at 2 days, and all test groups at 5 days(P<0.05). From the above results, mixed extracts of aralia cortex and phellodendron cortex appeared to enhance cellular activities including cell proliferation rate, protein levels and alkaline phosphatase activity of human gingival fibroblasts and periodontal ligament cells in normal and high glucose condition. This study suggests that mixed extracts of aralia cortex and phellodendron cortex seem to be able to subside the inflammation of periodontal tissue and regenerate the destructed periodontal tissue.