• Proceedings of the KSME Conference
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• 2000.11a
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• pp.432-437
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• 2000

The purpose of this paper is to determine a two dimensional axisymmetric model through a comparative study between a three dimensional and an axisymmetric finite element analysis of the reactor coolant piping nozzle subject to internal pressure. The finite element analysis results show that the stress adopting the axisymmetric model with the radius of equivalent spherical vessel are well agree with that adopting the three dimensional model. The the radii of equivalent spherical vessel are 3.5 times and 7.3 times of the radius of the reactor coolant piping for the safety injection nozzle and for the residual heat removal nozzle, respectively.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.4146-4158
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• 2023

This paper proposes a combined plastic and creep constitutive model of A533B1 pressure vessel steel to simulate progressive deformation of nuclear pressure vessels under severe accident conditions. To develop the model, recent tensile test data covering a wide range of temperatures (from RT to 1,100 ℃) and strain rates (from 0.001%/s to 1.0%/s) was used. Comparison with experimental data confirms that the proposed combined plastic and creep model can well reflect effects of temperature and strain rate on tensile behaviour up to failure. In the companion paper (Part II), the proposed model will be used to simulate OECD lower head failure (OLHF) test data.

• The Korean Nurse
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• v.35 no.3
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• pp.61-76
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• 1996

The purpose of this study was to develop a nursing care delivery system which can provide patient focused care and increase satisfaction for both patients and nurses. This study was a quasi-experimental study to test the effectiveness of direct / indirect nursing care hours, patient satisfaction, nurse's job satisfaction, and the difference of the length of stay between model and control group. Control group data were collected from 100 patients who had lumbar disease in the neuro-surgical unit and model group data were from 66 patients who didn't have family residents from August 21, 1995 to February 29, 1996. Model unit was operated by modified PPM(Professional Practical Model) system for 3 months from December 1, 1995 to February 29, 1996. Working committee empowered nurses to make a decision to provide increased opportunities for autonomy, accountability, and control over the environment in which they deliver care. Satisfaction survey was done twice and analyzed by the SPSS program. The results of the study were as follows; 1. Mean direct nursing care hours of the model group was 90.47 minutes as it was 28.04 in the control group which shows significant statistical difference (t=-18.0, P=0.000). 2. Patient satisfaction to nursing care of in the model group was significantly higher than the control group (t=-6. 77, P=0.000) and it apples to the all subcategories, too. 3. Nurse's job satisfaction shows the significant increase in the model group than the control group(Z=-3.0405, p=0.0024). 4. There was no statistical difference between 2 groups in average length of stay except for the post-op patient which shows 5.4 days less in the model group. This study shows that patient satisfaction and nurse's job satisfaction were increased and length of stay was decreased in the model group. Even though this new developed Patient - Nurse Oriented Model can provide nursing with the opportunity to improve patient care to increase productivity and highly valued, it is very difficult to practice due to the limited nursing resources, higher acuity levels and nursing care cost. It is strongly recommended that the government needs to look at the unreasonable reimbursement system and recognize the nursing care costs to the high acuity level patients. Otherwise, make the patient responsible for the nursing care cost so that we can provide more efficient and patient focused care.

• Food Science of Animal Resources
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• v.40 no.6
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• pp.938-945
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• 2020

A dynamic model was developed to predict the Escherichia coli cell counts in pig trotters at changing temperatures. Five-strain mixture of pathogenic E. coli at 4 Log CFU/g were inoculated to cooked pig trotter samples. The samples were stored at 10℃, 20℃, and 25℃. The cell count data was analyzed with the Baranyi model to compute the maximum specific growth rate (μ_max) (Log CFU/g/h) and lag phase duration (LPD) (h). The kinetic parameters were analyzed using a polynomial equation, and a dynamic model was developed using the kinetic models. The model performance was evaluated using the accuracy factor (A_f), bias factor (B_f), and root mean square error (RMSE). E. coli cell counts increased (p<0.05) in pig trotter samples at all storage temperatures (10℃-25℃). LPD decreased (p<0.05) and μ_max increased (p<0.05) as storage temperature increased. In addition, the value of h₀ was similar at 10℃ and 20℃, implying that the physiological state was similar between 10℃ and 20℃. The secondary models used were appropriate to evaluate the effect of storage temperature on LPD and μ_max. The developed kinetic models showed good performance with RMSE of 0.618, B_f of 1.02, and A_f of 1.08. Also, performance of the dynamic model was appropriate. Thus, the developed dynamic model in this study can be applied to describe the kinetic behavior of E. coli in cooked pig trotters during storage.

• Journal of the Korean Data and Information Science Society
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• v.21 no.1
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• pp.21-32
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• 2010

Graphical regression is a paradigm for obtaining regression information using plots without model assumptions. The general goal of this approach is to find lowdimensional sufficient summary plots without loss of important information. Model assessments using residual plots are less likely to be successful in models that are not linear. As an alternative approach, marginal model plots provide a general graphical method for assessing the model. We apply the methods of graphical regression and model assessment using marginal model plots to the logistic regression model.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.1 s.145
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• pp.32-42
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• 2006

This study aims at establishing a technique for sailing yachts model tests with sailing condition. It is very important to estimate a ship's potential speed performance before building a real ship. Several methods are used to estimate a ship's potential speed performance such as using parent ship data, standard vessel chart and model test. Model test is the most precise among these options. In korea. model testing is widely used with general vessels but not with sailing yachts. Because sailing yachts are propelled with heeling and leeway. using the wind. another method is needed to estimate their speed. The new model test. which is different from tests for upright general vessels, is in a great demand. In this paper. we describe a test method for the sailing yacht model test. based on Masuyama's equation of motion. And we describe choosing scale ratio. production process and materials of the model. Also. various ways of measuring instruments. attaching jigs and adjusting calibration are described so that they can be utilized as useful data for model testing.

• The Korean Journal of Applied Statistics
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• v.21 no.2
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• pp.183-200
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• 2008

Research for efficient management of the National Pension has been emphasized as the current society trends toward aging and low birth rate. In this article, we suggest a statistical model for effective classification and prediction of the reserve for the survivor's pension in Korea. Logistic regression model is incorporated; correct classification rate, and distribution of the posterior probability for the reserve of survivor's pension are investigated and compared with the results from the general logistic models. Assessment of predictive model is also done with lift graph, ROC curve and K-S statistic. We suggest strategies for reducing financial risks in managing and planning the pension as an application of the suggested model.

• Informatization Policy
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• v.20 no.1
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• pp.85-109
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• 2013

This study presents a model and its implementation methodology assessing not only maturity but also applicability in order to increase the practical usage of open source software(OSS). Since this model measures applicability which can not be assessed by the previous models, it is able to support users in many ways when they introduce OSS for the first time, replace commercial software with OSS, and compare OSS with commercial software. For the purpose of design and implementation of this model, we presented a methodology with 7 phases and conducted a survey to evaluate the appropriateness and reliability of the model. In addition, we proved the practical usability of the model by providing a practical example assessing maturity and applicability of OSS in the area of the infra category on the basis of the methodology. In the future, not only general users but also officers in charge of informatization will be able to select optimal OSS by using this model for industrial application. Therefore, the result of this research is expected to greatly contribute to OSS promotion policy.

• The Journal of Society for e-Business Studies
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• v.19 no.4
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• pp.31-43
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• 2014

These days a lot of cyber attacks are exploiting the vulnerabilities of S/W. According to the trend of vulnerabilities is announced periodically, security directions are suggested and security controls are updated with this trend. Nevertheless, cyber attacks like hacking during the year 2011 are increased by 81% compared to 2010. About 75% of these cyber attacks are exploiting the vulnerabilities of S/W itself. In this paper, we have suggested a VIR model, which is a spread model of malware infection for measuring economic loss by S/W vulnerability, by applying the SIR model which is a epidemic model. It is applied to estimate economic loss by HWP(Hangul word) S/W vulnerabilities.

• Transactions of Materials Processing
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• v.27 no.6
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• pp.363-369
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• 2018

This study measured the mechanical properties of an ash wood under various temperature and humidity conditions and a finite element model was developed to predict the behavior of the wood. A humidity-controlled chamber was developed and used for measuring the dimensional changes of woods under various humidity conditions. The thermal expansion coefficient and the elastic stiffness constants were measured by using a thermal chamber and the three-point bending test along the three principal axes of the wood. A constitutive model was proposed to describe the moisture content and temperature dependent behavior of wood. The proposed model was validated for the warping test of a wood plate. The warping of the plate was calculated using the finite element method. The calculated amount of warping was in consistence with the measurements.