• Smart Structures and Systems
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• v.21 no.4
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• pp.521-535
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• 2018

The main purpose of this paper is to predict missing absolute out-of-plane displacements and failure limits of infill walls by artificial neural network (ANN) models. For this purpose, two shake table experiments are performed. These experiments are conducted on a 1:1 scale one-bay one-story reinforced concrete frame (RCF) with an infill wall. One of the experimental models is composed of unreinforced brick model (URB) enclosures with an RCF and other is composed of an infill wall with bed joint reinforcement (BJR) enclosures with an RCF. An artificial earthquake load is applied with four acceleration levels to the URB model and with five acceleration levels to the BJR model. After a certain acceleration level, the accelerometers are detached from the wall to prevent damage to them. The removal of these instruments results in missing data. The missing absolute maximum out-of-plane displacements are predicted with ANN models. Failure of the infill wall in the out-of-plane direction is also predicted at the 0.79 g acceleration level. An accuracy of 99% is obtained for the available data. In addition, a benchmark analysis with multiple regression is performed. This study validates that the ANN-based procedure estimates missing experimental data more accurately than multiple regression models.

• Journal of Radiation Protection and Research
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• v.16 no.1
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• pp.53-72
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• 1991

An integrated model is developed in this paper for the performance assessment of high level radioactive waste repository. This integrated model consists of two simple mathematical models. One is a multiple-barrier failure model of the repository system based on constant failure rates which provides source terms to biosphere. The other is a biosphere model which has multiple pathways for radionuclides to reach to human. For the parametric uncertainty and sensitivity analysis for the risk assessment of high level radioactive waste repository, Latin hypercube sampling and rank correlation techniques are applied to this model. The former is cost-effective for large computer programs because it gives smaller error in estimating output distribution even with smaller number of runs compared to crude Monte Carlo technique. The latter is good for generating dependence structure among samples of input parameters. It is also used to find out the most sensitive, or important, parameter groups among given input parameters. The methodology of the mathematical modelling with statistical analysis will provide useful insights to the decision-making of radioactive waste repository selection and future researches related to uncertain and sensitive input parameters.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.1
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• pp.51-58
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• 1992

The primary objective of this study is the development of the system reliability analysis of offshore structures against progressive fatigue failure. Two methods based on the second moment reliability methods are used. One is the improved first order reliability method(IFORM) and the other is the modified probabilistic network evaluation technique(MPNET). Using idealized parallel member models, reliability analyses for progressive fatigue failures are carried out for various cases with multiple members composed of multiple connecting joints per member. Numerical results indicate that the effectiveness of the used methods over the conventional ones (i.e. the FORM and the PNET) increases very significantly as the number of failure modes of the system increases.

• Biomolecules & Therapeutics
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• v.25 no.1
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• pp.80-90
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• 2017

Initial discovery on sphingosine 1-phosphate (S1P) as an intracellular second messenger was faced unexpectedly with roles of S1P as a first messenger, which subsequently resulted in cloning of its G protein-coupled receptors, $S1P_{1-5}$. The molecular identification of S1P receptors opened up a new avenue for pathophysiological research on this lipid mediator. Cellular and molecular in vitro studies and in vivo studies on gene deficient mice have elucidated cellular signaling pathways and the pathophysiological meanings of S1P receptors. Another unexpected finding that fingolimod (FTY720) modulates S1P receptors accelerated drug discovery in this field. Fingolimod was approved as a first-in-class, orally active drug for relapsing multiple sclerosis in 2010, and its applications in other disease conditions are currently under clinical trials. In addition, more selective S1P receptor modulators with better pharmacokinetic profiles and fewer side effects are under development. Some of them are being clinically tested in the contexts of multiple sclerosis and other autoimmune and inflammatory disorders, such as, psoriasis, Crohn's disease, ulcerative colitis, polymyositis, dermatomyositis, liver failure, renal failure, acute stroke, and transplant rejection. In this review, the authors discuss the state of the art regarding the status of drug discovery efforts targeting S1P receptors and place emphasis on potential clinical applications.

• Archives of Craniofacial Surgery
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• v.18 no.2
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• pp.112-116
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• 2017

The ideal scalp reconstruction involves closure of the defect with similar hair-bearing local tissue in a single step. Various reconstructions can be used including primary closure, secondary healing, skin grafts, local flaps, and microvascular tissue transfer. A 53-year-old female patient suffered glioblastoma, which had recurred for the second time. The neuro-surgeons performed radial debridement and an additional resection of the tumor, followed by reconstruction using a serratus anterior muscle flap with a split-thickness skin graft. Unfortunately, the flap became completely useless and a bilateral rotation flap was used to cover the defect. Two month later, seroma with infection was found due to recurrence of the tumor. Additional surgery was performed using multiple perforator based island flap. The patient was discharged two weeks after surgery without any complications, but two months later, the patient died. Radical surgical resection of tumor is the most important curative option, followed by functional and aesthetic reconstruction. We describe a patient with a highly malignant tumor that required multiple resections and subsequent reconstruction. Repeated recurrences of the tumor led to the failure of reconstruction and our strategy inevitably changed, from reconstruction to palliative treatment involving fast and stable wound closure for the patient's comfort.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.14 no.1
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• pp.48-53
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• 2014

Smith-Lemli-Opitz syndrome (SLO) is a rare, autosomal recessive disease caused by an inborn error in cholesterol synthesis. Patients with this disease suffer from multiple malformations due to reduced activity of 7-dehydrocholesterol reductase (DHCR7), which increases 7-dehydrocholesterol (7DHC) and 8-dehydrocholesterol (8DHC) concentrations and decreases cholesterol concentration in body fluids and tissue. Here, we describe Korean siblings with SLO who were diagnosed recently, and performed a review of literature about Korean cases with SLO to date. Microcephaly and syndactyly of the second and third toes are the most common physical finding in SLOS patients. Other malformations including growth failure, cleft palate or bifid uvula, various heart malformation, genital ambiguity in males are also accompanied. Not all patients showed low levels of serum cholesterol, so DHCR7 mutation analysis can be helpful to confirmative diagnosis. Two mutations on p.R352 locus (p.R352W and p.R352Q) are commonly identified in Korean SLO patients. Although rare in Korea, SLO should be considered in the differential diagnosis of growth failure with intellectual disability, especially in patients with multiple congenital anomalies.

• Tuberculosis and Respiratory Diseases
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• v.53 no.2
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• pp.234-237
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• 2002

A 77-year-old female was admitted 3 hours after intentionally ingesting 5g of aluminum ammonium sulfate ('Alum') powder dissolved in water. Gastric lavage with normal saline, activated charcoal chelation, and supportive therapies were performed. She showed a high anion gap metabolic acidosis, which rapidly progressed to multiple organ failure including ARDS. The patient subsequently progressed to a refractory shock which eventually led to death.

• Journal of Chest Surgery
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• v.29 no.12
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• pp.1373-1376
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• 1996

From October 1993 to February 1996, 9 patients with Wolfr-Parkinson-White syndrome underwent surgical ablation of the accessory atrioventricular conduction pathways. The indications for surgical ablation we e radiofrequency ablation failure in 6 cases, multiple accessory pathways in 1 case, catheter tip fracture ducting catheter ablation in 1 case and additional procedure(redo mitral valve replacement due to valve thrombosis) in 1 case. There was no operative mortality. The postoperative complications were noted In 2 cases pericardial effusion and wound Infection. All patients had accessory atrioventricular connections ablated which were proven by surface ECG and follow-up electrophysiologic study and have remained free of symptomatic tachycardia. The indications for surgical treatment of Wolff-Parkinson-White syndrome are radiofrequency ablation failure, multiple pathways, or when additional procedures are required The present results were satisfactory.

• Journal of Preventive Medicine and Public Health
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• v.22 no.4 s.28
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• pp.454-465
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• 1989

In a small island community with a population of less than 100 residents, nine persons died and five experienced severe illnesses during the period from November 1986 to May 1988. Their initial symptoms were sore throat and fever. Renal failure and hepatitis developed within one week after the onset. Oral mucosal ulcer developed in some cases. After one week, progressive respiratory failure and dyspnea developed evidently and severe respiratory distress and hypoxia preceded those fatal cases. Chest X-ray findings revealed bilateral diffuse multiple cystic lesion with occasional multiple large emphysematous bullae. Based on these features paraquat poisoning was diagnosed and route of poisoning was investigated. In three sources of drinking water, trace amount of paraquat was detected in November 1988, six months after the incidence of recent fatal case. In November 1988, soybean sauces and soybean pastes from 12 households were found contaminated with high concentration of paraquat, the cause could not be identified. The possibility of the contamination of drinking water as the cause of this mass poisoning has been suggested.

• Journal of the Korean Society of Safety
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• v.38 no.6
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• pp.72-78
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• 2023

The purpose of this paper is to derive a quantified approach for Operator Manual Actions (OMAs) based on the existing fire Human Reliability Analysis (HRA) methodology developed by the Korea Atomic Energy Research Institute (KAERI). The existing fire HRA method was reviewed, and supplementary considerations for OMA quantification were established through a comparative analysis with NUREG-1852 criteria and the review of the existing literature. The OMA quantification approach involves a timeline that considers the occurrence of Multiple Spurious Operations (MSOs) during a Main Control Room Abandonment (MCRA) determination and movement towards the Remote Shutdown Panel (RSP) in the event of a Main Control Room (MCR) fire. The derived failure probability of an OMA from the approach proposed in this paper is expected to enhance the understanding of its reliability. Therefore, it allows moving beyond the deterministic classification of "reliable" or "unreliable" in NUREG-1852. Also, in the event of a nuclear power plant fire where multiple OMAs are required within a critical time range, it is anticipated that the OMA failure probability could serve as a criterion for prioritizing OMAs and determining their order of importance.