• Title/Summary/Keyword: failure case

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Static vulnerability of existing R.C. buildings in Italy: a case study

  • Maria, Polese;Gerardo M., Verderame;Gaetano, Manfredi
    • Structural Engineering and Mechanics
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    • v.39 no.4
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    • pp.599-620
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    • 2011
  • The investigation on possible causes of failures related to documented collapses is a complicated issue, primarily due to the scarcity and inadequacy of information available. Although several studies have tried to understand which are the inherent structural deficiencies or circumstances associated to failure of the main structural elements in a reinforced concrete frame, to the authors knowledge a uniform approach for the evaluation building static vulnerability, does not exist yet. This paper investigates, by means of a detailed case study, the potential failure mechanisms of an existing reinforced concrete building. The linear elastic analysis for the three-dimensional building model gives an insight on the working conditions of the structural elements, demonstrating the relevance of a number of structural faults that could sensibly lower the structure's safety margin. Next, the building's bearing capacity is studied by means of parametric nonlinear analysis performed at the element's level. It is seen that, depending on material properties, concrete strength and steel yield stress, the failure hierarchy could be dominated by either brittle or ductile mechanisms.

One Case Report of Chronic Renal Failure Patient Prescribed Gyulpyjeonwon (귤피전원(橘皮煎元)을 처방한 만성신부전 환자 1례에 대한 보고)

  • Jung, Gi-Hun;Chang, Sun-Kyu;Cho, Chung-Sik;Kim, Chul-Jung
    • Journal of Haehwa Medicine
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    • v.16 no.2
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    • pp.229-234
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    • 2007
  • Objectives : Chronic renal failure(CRF) is a pathophysiologic process with multiple etiologies, resulting in the inexorable attrition of nephron number and function and frequently leading to end-stage renal disease. It causes various symptoms(edema, general body weakness, nausea, anorexia, uremia, osteodystrophy and so on) which impair quality of life and long term complications. The purpose of this case is to report the improvement of a patient with chronic renal failure. Methods : We treated the patient with herbal medication(Gyulpyjeonwon) and measured the creatinine, BUN, albumin, hemoglobin in the serum. Results : Gyulpyjeonwon decreased serum creatinine and BUN level and increased serum albumin and hemoglobin level. And the symptoms of CRF(edema, general body weakness, anorexia) was improved significantly. Conclusions : This case suggests the efficacy of herbal medication(Gyulpyjeonwon) to patient who was involved CRF.

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Idiopathic infantile hypercalcemia with severe nephrocalcinosis, associated with CYP24A1 mutations: a case report

  • Yoo, Jeesun;Kang, Hee Gyung;Ahn, Yo Han
    • Childhood Kidney Diseases
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    • v.26 no.1
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    • pp.63-67
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    • 2022
  • Nephrocalcinosis often occurs in infants and is caused by excessive calcium or vitamin D supplementation, neonatal primary hyperparathyroidism, and genetic disorders. Idiopathic infantile hypercalcemia (IIH), a rare cause of nephrocalcinosis, results from genetic defects in CYP24A1 or SLC34A1. Mutations in CYP24A1, which encodes 25-hydroxyvitamin D 24-hydroxylase, disrupt active vitamin D degradation. IIH clinically manifests as failure to thrive and hypercalcemia within the first year of life and usually remits spontaneously. Herein, we present a case of IIH wih CYP24A1 mutations. An 11-month-old girl visited our hospital with incidental hypercalcemia. She showed failure to thrive, and her oral intake had decreased over time since the age of 6 months. Her initial serum parathyroid hormone level was low, 25-OH vitamin D and 1,25(OH)2 vitamin D levels were normal, and renal ultrasonography showed bilateral nephrocalcinosis. Whole-exome sequencing revealed compound heterozygous variants in CYP24A1 (NM_000782.4:c.376C>T [p.Pro126Ser] and c.1310C>A [p.Pro437His]). Although her hypercalcemia and poor oral intake spontaneously resolved in approximately 8 months, we suggested that her nephrocalcinosis and renal function be regularly checked in consideration of potential asymptomatic renal damage. Hypercalcemia caused by IIH should be suspected in infants with severe nephrocalcinosis, especially when presenting with failure to thrive.

Dam Failure and Unsteady Flow Analysis through Yeoncheon Dam Case(II) - Unsteady Flow Analysis of Downstream by Failure Scenarios - (연천댐 사례를 통한 댐 파괴 부정류해석 및 하류 영향 검토(II) -시나리오에 따른 댐 하류 부정류 해석 및 범랑특성 연구-)

  • Jang, Suk-Hwan
    • Journal of Environmental Science International
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    • v.17 no.11
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    • pp.1295-1305
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    • 2008
  • This study aims at the analyze of unsteady downstream flow due to dam failure along dam failure scenario and applied to Yeoncheon Dam which was collapsed August 1st 1999, using HEC-RAS simulation model. The boundary conditions of this unsteady flow simulation are that dam failure arrival time could be at 02:45 a.m. August 1st 1999 and failure duration time could be also 30 minutes. Downstream 19.5 km from dam site was simulated for unsteady flow analysis in terms of dam failure and non-failure cases. For the parameter calibration, observed data of Jeonkok station were used and roughness coefficient was applied to simulation model. The result of the peak discharge difference was 2,696 to $1,745\;m^3/sec$ along the downstream between dam failure and non-failure and also peak elevation of water level showed meanly 0.6m difference. Those results of these studies show that dam failure scenarios for the unknown failure time and duration were rational because most results were coincident with observed records. And also those results and procedure could suggest how and when dam failure occurs and downstream unsteady flow analyzes.

Fault Tolerant Control with Variable Time Weight (가변시간비중을 갖는 내고장성 제어)

  • Hee Gyoo Lee;Zeungnam Bien
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.29B no.4
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    • pp.22-30
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    • 1992
  • A redundant control scheme which can maintain its tracking capability in the case of a controller failure is proposed for the industrial applications which need high reliability with fault-tolerance. It consists of two identical controllers and a switching mechanism which includes failure detection and reconfiguration algorithm. The new detection method against controller failure using fuzzy logic enables the detection of controller failures without failure assumptions through the instability of the failed controller. The failed controller is smoothly removed from the control loop by reducing time weight of the failed controller.

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Correction of Acute Renal Failure After Mitral Valve Replacement: A Case Report (승모판 협착증 판막 이식후 발생한 급성 신부전증 치험 1예)

  • 조규석
    • Journal of Chest Surgery
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    • v.11 no.2
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    • pp.117-122
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    • 1978
  • With the increasing performance of open heart surgery during recent years, the occurrence of renal failure associated with cardiopulmonary aypass has received considerable attention. This patient was 33 yaar old woman who undertaken mitral valve replacement under the cardiopulmonary bypass. Acute renal failure developed after 2nd postoperative day. So we report here the course of renal failure as it occur in immediate relation to open heart surgery and examine the role of preoperative, intraoperative and postoderative factors.

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Fatal progressive right heart failure in a pancreatic cancer patient

  • Byoun, Jeong Tae;Cho, Jae Young
    • Journal of Yeungnam Medical Science
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    • v.37 no.2
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    • pp.122-127
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    • 2020
  • Pulmonary tumor thrombotic microangiopathy (PTTM) is a rare but fatal complication of cancer and causes pulmonary hypertension and acute/subacute right heart failure. PTTM is most commonly associated with gastric cancer and more rarely associated with pancreatic cancer. We report a case of progressive right heart failure associated with clinically diagnosed pancreatic cancer, suggesting PTTM.

Estimating Parameters of Field Lifetime Data Distribution Using the Failure Reporting Probability (고장 보고율을 이용한 현장 수명자료 분포의 모수추정)

  • Kim, Young Bok;Lie, Chang Hoon
    • Journal of Korean Institute of Industrial Engineers
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    • v.33 no.1
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    • pp.52-60
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    • 2007
  • Estimating parameters of the lifetime distribution is investigated when field failure data are not completelyreported. To take into account the reality and the accuracy of the estimates in such a case, the failure reportingprobability is incorporated in estimating parameters, Firstly, method of maximum likelihood estimate (MLE) isused to estimate parameters of the lifetime distribution when failure reporting probability is known, Secondly,Expectation and Maximization (EM) algorithm is used to estimate the failure reporting probability and parame-ters of the lifetime distribution simultaneously when failure reporting probability is unknown. For both cases,procedures of estimation are illustrated for single Weibull distribution and mixed Weibull distribution. Simula-tion results show that MLE obtained by the proposed method is more accurate than the conventional MLE.

Analysis of Discontinuity Distribution Property to Predict Rock Slope Failure (암반 사면의 파괴 예측을 위한 불연속면 분포 특성 분석)

  • 윤운상;김정환;배기훈
    • Proceedings of the Korean Geotechical Society Conference
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    • 1999.10a
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    • pp.147-152
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    • 1999
  • Distribution of fracture system is an important factor to analyse instability of jointed rock slope. In the most case of rock slopes, joint distribution properties are related to potential, shape, size and locality of slope failure. The purpose of this paper is to present an application of fracture characterization related to rock slope failure. Fracture data used in this study are collected by scanline survey. Two aspects of fracture characterization for rock slope are handled in this study First, In order to determine the potential and shape of slope failure, trace length of joints is considered as the weighting factor about collected orientation data. Second, Relationship between trace length and spacing is analysed to estimate failure location and size. The distribution of fracture system is directly influenced on wedge failure. It is effective to analyse the orientation of fractures by using weighting factors associated with the trace length of fractures rather than to analyse only that of fractures. It gives a conclusion that the wedge failure occurred along the peak of fracture density(or intensity) cycles.

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A Case of Brain Abscess in a Patient with Primary Mucociliary Transport Failure - Case Report - (원발성 점액섬모 이송기능 장애 환자에서 발생한 뇌농양 - 증례보고 -)

  • Yoon, Sung Hoon;Lee, Hyung Jin;Yi, Jin Seok;Yang, Ji Ho;Lee, Il Woo;Song, Kyu Sang;Kang, Joon Ki
    • Journal of Korean Neurosurgical Society
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    • v.30 no.12
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    • pp.1430-1434
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    • 2001
  • The authors present a case of brain abscess in a patient with primary mucociliary transport failure. Primary mucociliary transport failure is unfamiliar term to neurosurgeon. It encompasses three hereditary disorders, that is, primary ciliary dyskinesia, cystic fibrosis and Young's syndrome. Clinical manifestations in these disorders appear to overlap each other, e.g., male infertility and chronic sinopulmonary infections. These are characterized by ciliary dysfunction or abnormality of mucus secretion therefore recurrent infection occurs in organs containing the mucociliary transport system. Major causes of non-traumatic brain abscess are sinusitis and pulmonary infection. So the possibility of brain abscess is much higher if mucociliary transport failure exists. Especially, young patients who have brain abscess coexisting with chronic sinopulmonary infection should be considered primary mucociliary transport failure.

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