• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1998.03a
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• pp.113-116
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• 1998

A derivative based approach to process optimal design in powder forging is presented. The process model, the formulation for process optimal design, and the schemes for the evaluation of the design sensitivity, and an iterative procedure for the optimization are described in detail. The validity of the schemes for the evaluation of the design sensitivity is examined by performing numerical tests. The capability of the proposed approach to deal with diverse process parameters and objective functions is demonstrated through applications to some selected process design problems.

• Fashion & Textile Research Journal
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• v.6 no.4
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• pp.427-432
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• 2004

We evaluate what kinds of differences are existed to the visual sensitivity of college students m Daegu and Daejeon. Evaluation used the produced basic pattern to change modeling element of figure, direction, proportion, and color. The results are as below. The circle is preferred to the figure sensitivity and the triangle in Daegu and triangle and quadrangle in Daejeon is disliked. The direction sensitivity shows the difference of preferences according to figure. The angle of $0^{\circ}$ and $90^{\circ}$ which could be felt stability is preferred in general. In proportion sensitivity, the basic figure 1:1 rectangular proportions are preferred. The color sensitivity I shows the differences of preference according to figure and there are difference to the area in the degree of aversion.

• Journal of Electrical Engineering and Technology
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• v.8 no.4
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• pp.780-786
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• 2013

In the reliability-based design optimization of electromagnetic devices, the accurate and efficient reliability assessment method is very essential. The first-order sensitivity-assisted Monte Carlo Simulation is proposed in the former research. In order to improve its accuracy for wide application, in this paper, the second-order sensitivity analysis is presented by using the hybrid direct differentiation-adjoint variable method incorporated with the finite element method. By combining the second-order sensitivity with the Monte Carlo Simulation method, the second-order sensitivity-assisted Monte Carlo Simulation algorithm is proposed to implement reliability calculation. Through application to one superconductor magnetic energy storage system, its accuracy is validated by comparing calculation results with other methods.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.6
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• pp.685-691
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• 2014

The result of probabilistic maritime risk evaluation is represented by the probability(P=0.0~1.0) These results are shown by an index using Risk Acceptance Criteria(RAC) to base the evaluation generally to know the risk level easily. Current RAC is divided into 3 steps, 5 steps, 7 steps, etc. Despite need to evaluate whether the number of RAC for risk evaluation is reasonable, there is not a related research yet. In this study, It was proposed the evaluation method to determine the optimum index number of RAC using the Sensitivity distribution characteristics and the Sensitivity by the index number of RAC. As application result from the proposed method for probabilistic risk evaluation data obtained from the prior studies, It could be determined the optimum index number of RAC by Sensitivity below 10 times and confirmed that the proposed method is reasonable by this study.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.17 no.2
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• pp.126-136
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• 2021

During operation of nuclear power plants, the fatigue assessment should be conducted repeatedly, considering changes of operating environments. For the case that cumulative usage factors (CUFs) may exceed the acceptance limit, flaw tolerance evaluation can be an alternative method to meet the regulatory requirements. In this respect, this paper analyzes the effects of the input variables for flaw tolerance evaluation based on ASME BPVC Section XI Appendix L. The reference analysis is performed for the example problem in NUREG/CR-6934. Then effects of the crack orientation, stress intensity factor solutions, thermal stress profiles, fatigue stress decomposition and fatigue crack growth curves are considered for the sensitivity analysis. The results show that the stress analysis considering the actual environment plays a crucial role in flaw tolerance evaluation.

• Journal of applied mathematics & informatics
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• v.6 no.2
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• pp.631-638
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• 1999

Sensitive testing has been widely employed for many years in connection with the development and evaluation explosives detonation devices and propellants. Perhaps its earliest and possibly most important implementation was in biological studies of dosage mortality and response to drugs. Recently sensitivity experiments has been employed in the evaluation of new materials subject to stress in various environments and in delineanation of unstable combustion regions in chemical propulsion systems. This paper discussed a sta-tistical development of sensitivity testing.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2010.05a
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• pp.271-272
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• 2010

Sensitivity analysis by TSUNAMI clarifies the complex effects of key nuclides on the criticality probability quantitatively. As discussed above, the $K_{eff}$ of $UO_2$ fuel reaches the maximum value with 42w% concentration of intrusion water. The concentration of hydrogen affects the complexity of reaching criticality by its competition between the concentrations of $^{235}U$. Approximately if the weight percent of $H_2O$ in the mixture is less than 42%, the moderation effect of hydrogen surpasses its dilution effect on $^{235}U$. However, the importance of $^{235}U$ increases dramatically when the weight percent of water is bigger than 42%. In the sensitivity evaluation of $UO_2$ fuel employing TSUMAMI, there is a similar crosspoint of the sensitivity of $^{235}U$ and the sensitivity of $^1H$ where the criticality reaches summit. And the optimal water weight percent is determined to be 50%.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.4
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• pp.508-516
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• 2021

Although scientist have been reporting recently that changes in ocean environment influence the species composition, movements, and growth of fish in Korea waters. Previous studies on fish vulnerability owing to climate changes are insufficient to explain the effect of fluctuating ocean environments on fisheries ground. In this study, we suggested a method for the assessment of fisheries sensitivity to various factors in ocean environments in Korean waters. To evaluate the fisheries sensitivity, catch data (Chub mackerel, Hairtail, Common squid, small yellow croaker) from National federation of fisheries cooperatives in Korea (1991-2017) and oceanographic data from Korea Ocean Data Center (KODC; 1960-2017) were normalized using the z-score method. Thereafter, the fisheries sensitivity was calculated using the difference between the catch data and the oceanographic data. Finally, the fisheries sensitivity was evaluated based on evaluation grade ratings. Result revealed that in the south sea, variability in catch data was obviously higher than environmental fluctuation (evaluation grade 1), indicating that catch variability in response to environmental change is most sensitive in the south sea among Korean waters in 2017. These results would be helpful for fishery management and policy for sustainable yield in Korean waters.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.4
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• pp.1-12
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• 2008

The aim of this study is to investigate the sensitivity evaluation of human beings in reacting to the correlated color temperature of the optical properties of white LED lighting. For the sake of this study, white light-emitting diode modules have been fabricated their correlated color temperature have been measured, test cabinets for the sensitivity evaluation have been constructed with the white LED modules, and their sensitivity reactions on the test cabinets have been evaluated and analyzed. The sensitivity reaction has been evaluated by the semantic differential method with 15 selected questions, and the reliability and the content validity of their lighting have been analyzed to 3 factors which foe the activity as the first factor, the stability as the second one, the potency as the third one, respectively. For the data analysis on the sensitivity reaction, the dependent variable is the score of the sensitivity evaluation and the independent one is the correlated color temperature of the test module. The results of this study is as follows: In the case of the sensitive evaluation on the activity and the potency in the white LED lighting compared with the fluorescent lamp, the subjects have made higher mark on $MA_3$ with 8,300[K], and in the factor of the stability, they have made higher mark on $MA_1$ with 3,800[K].

• The Korean Journal of Nuclear Medicine Technology
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• v.27 no.1
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• pp.29-35
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• 2023

Purpose The concentration of PSA (Prostate Specific Antigen) after radical prostatectomy in prostate cancer patients is a predictor of biochemical recurrence, and the AUA (American Urological Association) is defined as biochemical recurrence when the concentration of PSA is measured at 0.2 ng/mL or more, and when the concentration is measured at 0.2 ng/mL or more at the retest. This standard is also applied our hospital. In this laboratory, the PSA reagent using IRMA (Immunoradiometric Assay) is used, and the sensitivity at a very low value was not as good as the reagent used in the department of laboratory medicine. This study aims to increase the reliability of the results by improving the precision and sensitivity of very low values. Materials and Methods As a reagent for the study, PSA reagent using IRMA was used. As a method to improve the precision and sensitivity of very low values, a variation method on the serum volume(25 uL, 50 uL, 100 uL, 200 uL) was studied, and variation usefulness evaluation was conducted. The evaluation items were compared the results of precision, analytical sensitivity, recovery rate, dilution test, high-dose hook effect test, parallel test and very low concentration values(n = 20). Results The validation results were displayed in the order of 25 uL, 50 uL, 100 uL, 200 uL. As the serum volume increased, it was confirmed that CV (Coefficient of Variation)(%) improved. Analytical sensitivity(ng/mL) was 0.038, 0.041, 0.017, 0.015 and recovery rate(%) was 101±3, 101±3, 99±2, 97±4. very low concentration values(ng/mL) between each volume(n=20) were 0.135±0.068, 0.076±0.050, 0.048±0.034, 0.046±0.034. and high dose hook effect appeared as the serum volume increased. Conclusion Through the variation usefulness evaluation, it was confirmed that as the serum volume increased, the precision and sensitivity improved at very low concentration values. However, it is necessary to pay special attention to the occurrence of high-dose hook effect as the serum volume increases. In the case of tests that requires very low concentration values, it is thought that the reliability of the result will be increased if the variation method is properly used after the variation usefulness evaluation.