• Title/Summary/Keyword: Common-cause failure

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Reliability Analysis system For Network with Dependent Components (종속을 고려한 Network동적 신뢰도 분석 시스템)

  • Yun, Won-Young;Ha, Young-Ju
    • IE interfaces
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    • v.10 no.2
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    • pp.41-50
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    • 1997
  • This paper considers the reliability computation of the network with dependent components and a software system is developed for supporting the reliability analysis and improvement of the system reliability. At first, We propose the common cause failure and load sharing models as the typical models considering the dynamic behaviors of networks with dependent components. Secondly, the algorithm is proposed to obtain the network reliability and reliability importance of component. The software, Delphi, is used to develop the our reliability analysis system.

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Systemic lupus erythematosus (전신성 홍반성 루푸스)

  • Kim, Kwang-Nam
    • Clinical and Experimental Pediatrics
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    • v.50 no.12
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    • pp.1180-1187
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    • 2007
  • Systemic lupus erythematosus (SLE) is an episodic, multi-system, autoimmune disease characterized by widespread inflammation of blood vessels and connective tissues and by the presence of antinuclear antibodies (ANAs), especially antibodies to native (double-stranded) DNA (dsDNA). Its clinical manifestations are extremely variable, and its natural history is unpredictable. Untreated, SLE is often progressive and has a significant fatality rate. The most widely used criteria for the classification of SLE are those of the American College of Rheumatology (ACR), which were revised in 1982 and modified in 1997. The presence of four criteria have been diagnosed as a SLE. Rashes are common at onset and during active disease. The oral mucosa is the site of ulceration with SLE. Arthralgia and arthritis affect most children and these symptoms are short in duration and can be migratory. Lupus nephritis may be more frequent and of greater severity in children than in adults. The initial manifestation of nephritis is microscopic hematuria, followed by proteinuria. The most common neuropsychiatric symptoms are depression, psychosis(hallucination and paranoia) and headache. CNS disease is a major cause of morbidity and mortality. Pericarditis is the most common cardiac manifestation. Libman-Sacks endocarditis is less common in children. The most frequently described pleuropulmonary manifestations are pleural effusions, pleuritis, pneunonitis and pulmonary hemorrhage. During the active phase ESR, CRP, gamma globulin, ferritin and anti-dsDNA are elevated. Antibodies to dsDNA occur in children with active nephritis. Antibodies to the extractable nuclear antigens (Sm, Ro/SS-A, La/SS-B) are strongly associated with SLE. Specific treatment should be individualized and based on the severity of the disease. Sepsis has replaced renal failure as the most common cause of death.

Study on Sanitary Management of Deceased Bodies through Categorical Analysis of Cause of Death (사망 원인별 유형 분석을 통한 사망자의 위생 관리에 대한 연구)

  • Choi, Jeungmok
    • The Journal of the Korea Contents Association
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    • v.17 no.7
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    • pp.265-275
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    • 2017
  • The aim of this study was to examine fluid excretions and changes in deceased bodies depending on type, location of, and causes of death for hygienic management of funeral homes. Based on the 858 cadavers studied, the average age at the time of death is 68.6 years, 83.0% had illness as the cause of death, and 79.5% passed away in a medical facility. Fluid excretion was observed in 46.2% of the cadavers. In manner of death, 78.8% of deaths -highest percentage- was due to an accident and 10.8% of deaths - lowest percentage- was due to age. Fluid excretion was observed in 46.3% of cadavers from medical facilities, 38.6% of cadavers from homes and 77.4% of cadavers from miscellaneous locations. There were various number of cadavers with recorded immediate, secondary and underlying cause of death; however, the fluid excretion rate was similar. In analyzing the immediate, secondary and underlying cause of death, respiratory and heart disease were the most common causes of death in categories of body organ and system. In terms of fluid excretion, liver disease followed by digestive and circulatory diseases were most common in immediate cause of death. Accidents and miscellaneous circumstances were most common amongst secondary and underlying causes of death for cadavers with fluid excretion. Based on the recorded illnesses of the cadavers, cardiopulmonary failure was most common as evident in 96 cadavers followed by pneumonia and sepsis. Cholangiocarcinoma (73.3%) had the highest rate of fluid excretion followed by pancreatic cancer, severe brain injury and liver cancer amongst categories of illnesses with more than 15 cadavers.

International case study comparing PSA modeling approaches for nuclear digital I&C - OECD/NEA task DIGMAP

  • Markus Porthin;Sung-Min Shin;Richard Quatrain;Tero Tyrvainen;Jiri Sedlak;Hans Brinkman;Christian Muller;Paolo Picca;Milan Jaros;Venkat Natarajan;Ewgenij Piljugin;Jeanne Demgne
    • Nuclear Engineering and Technology
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    • v.55 no.12
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    • pp.4367-4381
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    • 2023
  • Nuclear power plants are increasingly being equipped with digital I&C systems. Although some probabilistic safety assessment (PSA) models for the digital I&C of nuclear power plants have been constructed, there is currently no specific internationally agreed guidance for their modeling. This paper presents an initiative by the OECD Nuclear Energy Agency called "Digital I&C PSA - Comparative application of DIGital I&C Modelling Approaches for PSA (DIGMAP)", which aimed to advance the field towards practical and defendable modeling principles. The task, carried out in 2017-2021, used a simplified description of a plant focusing on the digital I&C systems important to safety, for which the participating organizations independently developed their own PSA models. Through comparison of the PSA models, sensitivity analyses as well as observations throughout the whole activity, both qualitative and quantitative lessons were learned. These include insights on failure behavior of digital I&C systems, experience from models with different levels of abstraction, benefits from benchmarking as well as major contributors to the core damage frequency and those with minor effect. The study also highlighted the challenges with modeling of large common cause component groups and the difficulties associated with estimation of key software and common cause failure parameters.

A Case Study of Continuous Improvement Methodology by Calculated Quality-Cost (품질비용 산정에 의한 지속적 개선 방법 사례 연구)

  • Lee, Kang-In;Han, Seok-Man
    • Journal of Korean Society for Quality Management
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    • v.33 no.3
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    • pp.19-30
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    • 2005
  • Recently many organization to become survival in changing marketplace, they must commit to implementing tools, systems, and quality management techniques. In this paper we develop process method of Team's problem-solving to reduce in failure costs. This paper suggest the step process how to measure quality cost reasonably that works in all types organizations. Or what is continuous improvement? Continuous improvement can be described as the continuous reduction of variation. Variation has many sources(machines, methods, materials, measurements, people, and environments) and cause(special & common in organization). As quality cost are not the answer to every organization financial, or quality-related problem, it's real results are designing & implementing quality cost system might be the answer.

Trends of the Precedent Case concerning Hospitalized Acquired Infection (병원감염에 관한 판례의 동향)

  • Lee, Dong-Pil
    • The Korean Society of Law and Medicine
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    • v.8 no.1
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    • pp.61-105
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    • 2007
  • The Hospitalized Acquired Infection is defined as the case where the hidden infection or not found at the time of hospitalization occurs during the hospitalized period or, within 30 days to those who performed the surgery operation and then left the hospital. About 2/3 of the Hospitalized Acquired Infection are found as having the internal infection cases that are occurred by the patients' own virus due to the lowered immune system, while about 1/3 are found as having the external infection. The latter 1/3 of the external infection cases can be prevented through the infection management. And in case the new Hospitalized Acquired Infection case occur to the patient who was treated in the hospital, its responsibility issue will matter. As well in the disputes over the Hospitalized Acquired Infection cases, the cause-result relation between the damages and the medical staff's fault and as to whether there is failure of the medical staff or not. personnel should be proved in the medical-malpractice cases. In addition, the difficulties in proving such as expertise, secrecy propensity, discrete propensity and incompleteness will be considered to ease the burden of patient side's proving. Probability theory, Fact based assumption theory, Most adequate plaintiff preassumption or Expressed evidence theories are being discussed as the theories of eased burden of proof. In the result of gathering and reviewing Korea's precedent cases concerning the Hospitalized Acquired Infection, there are only a few accumulated prece dent cases and the attitude of the court also are also not consistent. Therefore, there are the precedents where the cause-result relation and the failure are immediately assumed when (1) timely proximity between the medical behavior and malpractice results, (2) proximity between the medical behavior-applied parts and the malpractice results-found parts, and (3) lack of other causes are separately evidenced; while the are the precedents only when 'the existence of the medical faults based on the common sense' is separately evidenced. It was found that the former and latter cases coexisted. The former is considered as based on the theory that separates the fault and cause-result relation not to consider them together, or regarded as based on the doubts that assumes the medical staff's neglect even though the Hospitalized Acquired Infection might be completely prevented by their efforts. However, the modern medical technology has the limitation as far as the prevention of the Hospitalized Acquired Infection. In conclusion, the assumption of the cause-result relation and that of the fault should be separately reviewed. Therefore, the latter precedents are considered as more reasonable, in the point the faulty behavior may be proved based on the common sense.

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Identification of LAMP2 mutations in early-onset hypertrophic cardiomyopathy by targeted exome sequencing

  • Gill, Inkyu;Kim, Ja Hye;Moon, Jin-Hwa;Kim, Yong Joo;Kim, Nam Su
    • Journal of Genetic Medicine
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    • v.15 no.2
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    • pp.87-91
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    • 2018
  • X-linked dominant mutations in lysosome-associated membrane protein 2 (LAMP2) gene have been shown to be the cause of Danon disease, which is a rare disease associated with clinical triad of cardiomyopathy, skeletal myopathy, and mental retardation. Cardiac involvement is a common manifestation and is the leading cause of death in Danon disease. We report a case of a 24-month-old boy with hemizygous LAMP2 mutation who presented with failure to thrive and early-onset hypertrophic cardiomyopathy. We applied targeted exome sequencing and found a novel hemizygous c.692del variant in exon 5 of the LAMP2 gene, resulting a frameshift mutation p.Thr231Ilefs*11. Our study indicates that target next-generation sequencing can be used as a fast and highly sensitive screening method for inherited cardiomyopathy.

CONSTRUCTION ERROR TYPES - THE EXECUTION STAGE OF DUBAI PROJECTS

  • Hamad Aljassmi;Sangwon Han
    • International conference on construction engineering and project management
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    • 2011.02a
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    • pp.459-467
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    • 2011
  • Construction errors can have significant effects on project performance. Yet, any attempt to tackle error should be driven by the ability to understand its archetypal nature. This study aims to analyze a variety of construction errors at the execution stage, in order to develop a comprehensive set of categories that shall provide insights about the effect of different error types on the industry. We investigate a database provided by an authoritative source, which includes a number of 256 construction errors that occurred in the year 2009 in Dubai construction industry. Results from this study reveal that the most common error arose from 'poor workmanship' which accounted for 21% of the total encountered faults. The next most common types arose from the 'usage of impaired materials', followed by the 'deviation from an intended dimension'. These observations infer that the majority of construction errors are driven by workers' lack of skill or competence. Moreover, it suggests that execution-oriented errors are the major cause of faults and accidents rather than design errors.

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Pulse-Width Modulation Strategy for Common Mode Voltage Elimination with Reduced Common Mode Voltage Spikes in Multilevel Inverters with Extension to Over-Modulation Mode

  • Pham, Khoa-Dang;Nguyen, Nho-Van
    • Journal of Power Electronics
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    • v.19 no.3
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    • pp.727-743
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    • 2019
  • This paper presents a pulse-width modulation strategy to eliminate the common mode voltage (CMV) with reduced CMV spikes in multilevel inverters since a high CMV magnitude and its fast variations dv/dt result in bearing failure of motors, overvoltage at motor terminals, and electromagnetic interference (EMI). The proposed method only utilizes the zero CMV states in a space vector diagram and it is implemented by a carrier-based pulse-width modulation (CBPWM) method. This method is generalized for odd number levels of inverters including neutral-point-clamped (NPC) and cascaded H-bridge inverters. Then it is extended to the over-modulation mode. The over-modulation mode is implemented by using the two-limit trajectory principle to maintain linear control and to avoid look-up tables. Even though the CMV is eliminated, CMV spikes that can cause EMI and bearing current problems still exist due to the deadtime effect. As a result, the deadtime effect is analyzed. By taking the deadtime effect into consideration, the proposed method is capable of reducing CMV spikes. Simulation and experimental results verify the effectiveness of the proposed strategy.

Etiology and clinical characteristics of fever of unknown origin in children: a 15-year experience in a single center

  • Kim, Yi-Seul;Kim, Kyung-Ran;Kang, Ji-Man;Kim, Jong-Min;Kim, Yae-Jean
    • Clinical and Experimental Pediatrics
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    • v.60 no.3
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    • pp.77-85
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    • 2017
  • Purpose: Fever is one of the most common symptoms in children. In previous studies, infectious disease was the most common cause of pediatric fever of unknown origin (FUO). The aim of this study is to investigate the etiology, clinical characteristics and prognosis of pediatric FUO in 21 century with more diagnostics available and to analyze the factors for certain disease categories. Methods: Among the children under 18 years old who were hospitalized at Samsung Medical Center from January 2000 to December 2014, the patients who met the criteria including fever of ${\geq}38.0^{\circ}C$ for longer than ${\geq}14days$ and failure to reach a diagnosis after one week of investigations were included. Results: Total 100 patients were identified. Confirmed diagnosis was achieved in 57 patients (57%). Among them, infectious diseases (n=19, 19%) were most common, followed by connective tissue diseases (n=15, 15%), necrotizing lymphadenitis (n=8, 8%), and malignancies (n=7, 7%). Children with fever duration over 28 days had a trend for higher frequency of connective tissue diseases (28.3%) except undiagnosed etiology. The symptoms such as arthritis, lymph node enlargement and only fever without other symptoms were significantly related with connective tissue diseases, necrotizing lymphadenitis and undiagnosed respectively (P<0.001). Ninety-two patients have become afebrile at discharge and 1 patient died (1%). Conclusion: Almost half of our patients were left without diagnosis. Although it has been known that infectious disease was most common cause of pediatric FUO in the past, undiagnosed portion of FUO have now increased due to development of diagnostic techniques for infectious diseases.