• Nuclear Engineering and Technology
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• v.15 no.4
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• pp.229-235
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• 1983

Common Mode Failures (CMFs) have been a serious concern in the nuclear power plant. There is a broad category of the failure mechanisms that can cause common mode failures. This paper is a theoretical investigation of the CMFs on the unavailability of the redundant system. It is assumed that the total CMFs consist of the potential CMFs and the dependent human error CMFs. As the human error dependence is higher, the total CMFs are more effected by the dependent human error. If the human error dependence is lower, the system unavailability strongly depends on the potential CMFs, rather than the mechanical failure or the dependent human error. And it is shown that the total CMFs are dominant factor to the unavailability of the redundant system.

• Tuberculosis and Respiratory Diseases
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• v.46 no.5
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• pp.718-722
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• 1999

Thymoma is the most common tumor in the compartment of anterior mediastinum. The malignant thymoma is classified into invasive thymoma(category I) and thymic carcinoma(category II). Recently, well-differentiated thymic carcinoma is a proposed category 1.5 used to describe a subset of thymic epithelial tumors, allowing for the existence of intermediate form based on the clinical features and the histological characteristics. Thymic cyst is a congenital or a acquired disorder. Congenital thymic cyst may develop due to failure of the thymopharyngeal duct to obliterate and acquired thymic cyst develops from inflammation(multilocular thymic cyst), or neoplasm(cystic thymoma). Cystic degeneration in thymoma is a relatively frequent but focal event. In rare cases, the process proceeds to the extent that most or all of the lesion becomes cystic. Until now, well-differentiated thymic carcinoma with extensive cystic degeneration has not been reported in our country. We experienced a case of 14 year-old female patient showing extensive cystic degeneration in well-differentiated thymic carcinoma. And so we report it with review of the articles related.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.396-401
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• 1995

Epoxy coated reinforcing steels (ECRs) were acquired from ten sources and coatings from each source were initially characterized in terms of defects, thickness, solvent extraction weight loss and hardness. Testing involved exposure in three aqueous solutions at elevated temperature (8$0^{\circ}C$) and in chloride-contaminated concrete slabs under outdoor exposure, It was found that the density and size of coating defects was the promary factor affecting ECR performance. The equivalent circuit analysis using electrochemical impedance spectroscopy (EIS) data indicated that the impedance response for well-performing ECR specimens showed no signs of active degradation at the interface although diffusional processes similar to those noted for poorly performing bars occurred here. Experimental results also indicated a relationship between corrosion behavior and bar source. Weight loss upon solvent extraction correlated with impedance reduction from hot water exposure. Coating defects during most of the tests, especially in high pH solutions containing chloride ions. ECRs with excessive coating defects, either initially present or ones which developed in service, performed poorly in every test category regardless of source. Forms of coating failure were extensive rusting at defects, blistering, wet adhesion loss, cathodic delamination, underfilm corrosion and coating cracks. These occurred sequentially or concurrently, depending on the condition of the ECR and nature of the environment

• Journal of Korean Society for Quality Management
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• v.39 no.4
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• pp.507-515
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• 2011

MIL-HDBK-217 has played a pivotal role in reliability prediction of electronic equipments for more than 30 years. Recently, RIAC developed a new methodology $217Plus^{TM}$which officially replaces MIL-HDBK-217. Sensitivity analysis of the 217Plus component models to various parameters has been performed and meaningful observations have been drawn in this study. We first briefly reviewed the $217Plus^{TM}$ methodolog and compared it with the conventional model, MIL-HDBK-217. We then performed sensitivity analysis $217Plus^{TM}$ component models to various parameters. Based on the six parameters and an orthogonal array selected, we have performed indepth analyses concerning parameter effects on the model. Our result indicates that, among various parameters, operating temperature and temperature rise during operation have the most significant impacts on the life of a component, and thus a design robust to high temperature is the most importantly required. Next, year of manufacture, duty cycle, and voltage stress are weaker but may be significant when they are in heavy load conditions. Although our study is restricted to a specific type of diodes, the results are still valid to other cases. The results in this study not only figure out the behavior of the predicted failure rate as a function of parameters but provide meaningful guidelines for practical applications.

• Research in Community and Public Health Nursing
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• v.23 no.4
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• pp.427-437
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• 2012

Purpose: In order to lower the infection rate and the reinfection rate of Clonorchiasis in high-risk areas, we performed and analyzed a case management on people with chlonorchisis. Methods: The data was collected from April 2010 to March 2011. A community health practitioner was selected as a case manager based on our training program. The intervention group had 58 participants with three months of case management and the control group had 144 participants handled with traditional methods. Results: the pre and post-test in the intervention group and the control group showed us improved knowledge of Clonorchiasis, attitudes and behavior toward eating freshwater fish. The results of post-test between the intervention group and the control group showed statistically significant differences in all categories, except a hand-washing category. However, one year after a case management, there was no significant difference in the failure rate of treatment. Conclusion: The case management was effective for people infected with Clornorchiasis near riverside areas; however, in order to lower the rates of reinfection and treatment failure, it is necessary to perform continuous monitoring and regular evaluations.

• Steel and Composite Structures
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• v.13 no.3
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• pp.295-308
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• 2012

This paper experimentally investigated the buckling capacity of built-up steel columns mainly, Cruciform Columns (CC) and Side-to-Side (SS) columns fabricated from two Universal Beam (UB) sections. A series of nine experimental tests comprised of three UB sections, three CC sections and three SS sections with different lengths were tested to failure to measure the ultimate axial capacity of each column section. The lengths used for each category of columns were 1.8, 2.0, and 2.2 m with slenderness ratios ranging from 39-105. The measured buckling loads of the tested specimens were compared with the predicted ultimate axial capacity using Eurocode 3, AISC LRFD, and BS 5959-1. It was observed that the failure modes of the specimens included flexural buckling, local buckling and flexural-torsional buckling. The results showed that the ultimate axial capacity of the tested cruciform and side-by-side columns were higher than the code predicted design values by up to 20%, with AISC LRFD design values being the least conservative and the Eurocode 3 design values being the most conservative. This study has concluded that cruciform column and side-to-side welded flange columns using universal beam sections are efficient built-up sections that have larger ultimate axial load capacity, larger stiffness with saving in the weight of steel used compared to its equivalent universal beam counterpart.

• Nuclear Engineering and Technology
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• v.50 no.8
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• pp.1234-1245
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• 2018

The risk of multi-unit nuclear power plants (NPPs) at a site has received considerable critical attention recently. However, current probabilistic safety assessment (PSA) procedures and computer code do not support multi-unit PSA because the traditional PSA structure is mostly used for the quantification of single-unit NPP risk. In this study, the main purpose is to develop a multi-unit Level 2 PSA method and apply it to full-power operating six-unit OPR1000. Multi-unit Level 2 PSA method consists of three steps: (1) development of single-unit Level 2 PSA; (2) extracting the mapping data from plant damage state to source term category; and (3) combining multi-unit Level 1 PSA results and mapping fractions. By applying developed multi-unit Level 2 PSA method into six-unit OPR1000, site containment failure probabilities in case of loss of ultimate heat sink, loss of off-site power, tsunami, and seismic event were quantified.

• Journal of English Language & Literature
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• v.57 no.1
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• pp.51-72
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• 2011

This paper explores the issue of strangers and of hospitality in Mary Shelley's Frankenstein, based on Kant's concept of hospitality as "the right of a stranger" and on Derrida's discussion of hospitality. It first examines the similarities between the domestic relations within the Frankenstein family and Frankenstein's relation to the monster: an effort to create unity out of a multiplicity of elements, and what can be called a "debt economy." Then, reading the animation scene of the monster as a version of the advent of a stranger, it deals with the question of hospitality. More specifically, the arrival of Clerval immediately follows the animation of the monster because it effectively dramatizes the paradox that there is no hospitality without hostility. The opposition and the apposition between hospitality and hostility are also seen in the De Lacey family's welcoming Safie and rejecting the monster. Frankenstein's failure and the De Lacey family's failure to welcome the monster show that hospitality as "right" exemplified by Kantian hospitality does not apply to a stranger like the monster who has neither name nor relation and who is categorized into what Derrida terms "an absolute other." This paper also looks at Safie's problematic subversion against her father, which loses its subversive charge in the context of racial relations between Turkish Mahometans and European Christians. Safie's father looms large in the context of the issue of hospitality because his episode suggests that the category of race causes hospitality to malfunction.

• Advances in Computational Design
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• v.8 no.2
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• pp.97-112
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• 2023

The Finite Element (FE) modeling of Reinforced Concrete (RC) under seismic loading has a sensitive impact in terms of getting good contribution compared to experimental results. Several idealized model types for simulating the nonlinear response have been developed based on the plasticity distribution alone the model. The Continuum Models are the most used category of modeling, to understand the seismic behavior of structural elements in terms of their components, cracking patterns, hysteretic response, and failure mechanisms. However, the material modeling, contact and nonlinear analysis strategy are highly complex due to the joint operation of concrete and steel. This paper presents a numerical simulation of a chosen RC column under monotonic and cyclic loading using the FE Abaqus, to assessthe hysteretic response and failure mechanisms in the RC columns, where the perfect bonding option is used for the contact between concrete and steel. While results of the numerical study under cyclic loading compared to experimental tests might be unsuccessful due to the lack of bond-slip modeling. The monotonic loading shows a good estimation of the envelope response and deformation components. In addition, this work further demonstrates the advantage and efficiency of the damage distributions since the obtained damage distributions fit the expected results.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.72-82
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• 2016

Various studies have been done in medical service area but they have just focused on the examination of the relationships between cause and effect variables. This study, thus, empirically analyzed qualitative data regarding medical service problems using word cloud technique. The major results of the paper are as follows. The data reveal ten sources in medical service - forced treatment, excess inspection, misdiagnosis, carelessness, inexperienced service, waiting for emergency, reservation problem, unkindness, process problem, and inconvenience. Major words in the category of irrecoverable service failure are misdiagnosis, careless treatment, and inexperienced service whereas those in recoverable service failure are unkind attitude and negative experience in reservation system. Those who experienced a medical service problem are usually engaged in a public act and they make public protests and legal action against very severe problems. The conclusion of this study also suggests a summary, implication, and agenda of the research.