• 제목/요약/키워드: Cause Diagnosis

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Development of an Expert System (ESRCP) for Failure Diagnosis of Reactor Coolant Pumps (원자로냉각재펌프 고장진단을 위한 전문가시스템의 개발)

  • Cheon, Se-Woo;Chang, Soon-Heung
    • Nuclear Engineering and Technology
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    • v.22 no.2
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    • pp.128-138
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    • 1990
  • This paper presents a prototype expert system (ESRCP) for Reactor Coolant Pumps. The purpose of this system is to diagnose RCP failures and to offer corrective operational guides to plant operators. The first symptoms for the diagnosis are the alarms which are related to the RCP domain. Alarm processing is required to find a primary causal alarm when multiple alarms occur. The system performs the alarm processing by rule-based deduction or priority factor operation. To diagnose the RCP failure, the system performs rule-based deduction or Bayesian inference. Various sensor readings are required as symptoms to infer a root cause. When the symptoms are insufficient or uncertain to diagnose accurately, Bayesian inference is performed.

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Brown Tumor of the Thoracic Spine : First Manifestation of Primary Hyperparathyroidism

  • Sonmez, Erkin;Tezcaner, Tugan;Coven, Ilker;Terzi, Aysen
    • Journal of Korean Neurosurgical Society
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    • v.58 no.4
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    • pp.389-392
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    • 2015
  • Brown tumors also called as osteoclastomas, are rare nonneoplastic lesions that arise in the setting of primary or secondary hyperparathyroidism. Parathyroid adenomas or hyperplasia constitute the major Brown tumor source in primary hyperparathyroidism while chronic renal failure is the leading cause in secondary hyperparathyroidism. Most of the patients with the diagnosis of primary hyperparathyroidism present with kidney stones or isolated hypercalcemia. However, nearly one third of patients are asymptomatic and hypercalcemia is found incidentally. Skeletal involvement such as generalized osteopenia, bone resorption, bone cysts and Brown tumors are seen on the late phase of hyperparathyroidism. The symptoms include axial pain, radiculopathy, myelopathy and myeloradiculopathy according to their locations. Plasmocytoma, lymphoma, giant cell tumors and metastates should be ruled out in the differential diagnosis of Brown tumors. Treatment of Brown tumors involve both the management of hyperparathyroidism and neural decompression. The authors report a very rare spinal Brown tumor case, arisen as the initial manifestation of primary hyperparathyroidism that leads to acute paraparesis.

Fine Needle Aspiration Cytology of Pilomatrixoma - Two Cases Report - (모기질세포종의 세침흡인 세포학적 소견 - 2예 보고 -)

  • Paik, Seung-Sam;Kim, Dong-Hoon;Lee, How-Jin;Jang, Se-Jin;Park, Moon-Hyang;Lee, Jung-Dal
    • The Korean Journal of Cytopathology
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    • v.8 no.2
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    • pp.155-159
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    • 1997
  • Pilomatrixoma is a benign skin appendage tumor of hair matrix cell origin. The cytological appearance of this tumor may cause problems when attempting to establish a differential diagnosis with other neoplasms. Herein we report the aspiration cytology findings of two cases of pilomatrixoma. One case was diagnosed as atypical cell clusters initially and the other was diagnosed as pilomatrixoma. On cytologic examination, both cases showed clusters of tightly arranged basaloid cells with an uniform appearance, scanty cytoplasm and round hyperchromatic nuclei. There were histiocytes and multinucleated foreign body giant cells merged with the amorphous opaque orangeophilic materials of "ghost cells". The differential diagnosis with other neoplasms is discussed.

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Ultrasonographic Diagnosis of Soft Tissue Tumor that was Misdiagnosed as Achilles Tendinitis (초음파로 진단한 아킬레스건염으로 오인된 발목 후방의 종양 -증례 보고-)

  • Nam, Woo Dong;Kim, Ui Seok;Han, Kye Yong;Lee, Kang
    • The Journal of Korean Orthopaedic Ultrasound Society
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    • v.5 no.2
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    • pp.102-105
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    • 2012
  • Schwannoma is a common peripheral nerve tumor that mainly occur at head and neck, flexor muscle of upper, and lower extrimity. In posterior tibial nerve schwannoma, diagnosis is difficult, since physicians often consider achilles tendinitis, posterior impingement syndrome, retrocalcaneal bursitis, or injury of the flexor tendons, as the primary cause in patients with posterior ankle pain. Ultrasonogram may be a simple tool to differentiate such various diseases. The authors report a case of posterior tibial nerve schwannoma diagnosed with ultrasonogram, which was initially misunderstood as achilles tendinitis.

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Development of Diagnostic Expert Systems for A Rotor System (로터시스템의 이상진단시스템에 대한 연구)

  • Kim, Sung-Chul;Kim, Sang-Pyo;Kim, Young-Jin
    • Journal of Korean Institute of Industrial Engineers
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    • v.27 no.1
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    • pp.61-68
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    • 2001
  • A rotor system is composed of a rotating shaft with supporting bearings. The rotor system is widely used in every rotating machinery such as the turbine generator and the high precision machine tools. A negligible error or malfunction in the rotor, however, can cause a catastrophic failure in the system then result in the environmental and economic disasters. A diagnosis of the rotor system is important in preventing these kinds of failures and disasters. Up to now, many researchers have devoted in the development of diagnosing tools for the system. The basic principles behind the tools are to retrieve the data through the sensors for a specific state of the system and then to identify the specific state through the heuristic methods such as neural network, fuzzy logic, and decision matrix. The proper usage of the heuristic methods will enhance the performance of the diagnostic procedure when together used with the statistical signal processing. In this paper, the methodologies in using the above 3 heuristic methods for the diagnostics of the rotor system are established and also tested and validated for the data retrieved from the rolling element bearing and journal bearing supported system.

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The Analysis and Experimental Investigation of the Diagnosis of Rotor Faults for the Squirrel Cage Induction Motor (농형유도전동기의 회전자 불량진단에 관한 해석 및 실험적 고찰)

  • Kim, Chang-Eob;Chung, Gyo-Bum
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.21 no.3
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    • pp.27-34
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    • 2007
  • The rotor faults of induction motors may cause bad effects on the performance of the induction motor. This paper proposes the detecting technique of these faults by analyzing the waveform of the induced current and voltage of search coil using numerical analysis and the experiment. Several defective rotor bars are simulated to analyze the fault conditions-broken bars and high resistance of rotor bars. In order to prove the usefulness of the proposed method, we made an prototype experimental apparatus. The waveform of the induced voltages in search coil has the obvious characteristics and it is easy to differentiate the normal rotor from the abnormal one. The experimental results show that the proposed method is useful to detect the rotor fault conditions.

Practical stepwise approach to rhythm disturbances in congenital heart diseases

  • Huh, June
    • Clinical and Experimental Pediatrics
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    • v.53 no.6
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    • pp.680-687
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    • 2010
  • Patients with congenital heart diseases (CHD) are confronted with early- and late-onset complications, such as conduction disorders, arrhythmias, myocardial dysfunction, altered coronary flow, and ischemia, throughout their lifetime despite successful hemodynamic and/or anatomical correction. Rhythm disturbance is a well-known and increasingly frequent cause of morbidity and mortality in patients with CHD. Predisposing factors to rhythm disturbances include underlying cardiac defects, hemodynamic changes as part of the natural history, surgical repair and related scarring, and residual hemodynamic abnormalities. Acquired factors such as aging, hypertension, diabetes, obesity, and others may also contribute to arrhythmogenesis in CHD. The first step in evaluating arrhythmias in CHD is to understand the complex anatomy and to find predisposing factors and hemodynamic abnormalities. A practical stepwise approach can lead to diagnosis and prompt appropriate interventions. Electrophysiological assessment and management should be done with integrated care of the underlying heart defects and hemodynamic abnormalities. Catheter ablation and arrhythmia surgery have been increasingly applied, showing increasing success rates with technological advancement despite complicated arrhythmia circuits in complex anatomy and the difficulty of access. Correction of residual hemodynamic abnormalities may be critical in the treatment of arrhythmia in patients with CHD.

A Study on the Effects of Immediate Side Shift to the Pantographic Reproducibility Index (Immediate Side Shift가 Pantographic Reproducibility Index에 끼치는 영향에 관한 연구)

  • Nam, Cheon Woo;Han, Kyung Soo
    • Journal of Oral Medicine and Pain
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    • v.12 no.1
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    • pp.75-83
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    • 1987
  • This study was designed to investigate the effects of TMJ incoordination to condylar movements, especially, the ISS. The sounds are one of the symptoms in TMJ incoordinated disorder, and it may cause the changes of mandibular movement trajectory. 19 students with only TMJ sounds and 16 students with no TMJ problems participated in this study. The subject performed Rt. lateral, Lt. lateral and protrusive movements, and repeated 3 times on each movement. Pantronic was used to record the measures of condylar movement paths. The obtained results were as follows : 1. The mean values of RISS and LISS in control group were 0.29mm, 0.36mm respectively, and those in experimental group were 0.49mm, 0.41mm repectively. The mean values of RISS was higher in experimental group than that of RISS in control group. 2. Correlation coefficients between PRI and RISS, LISS were slightly higher in experimental group than those in control group, therefore, PRI was more likely to be affected by ISS in experimental group. 3. In control group PRI was correlated to RISS, LORB, RPRO and LPRO, but in experimental group PRI was not correlated to those items. From the study, the author knew that the condylar movements was stable in control group.

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Biomarkers for Evaluation of Prostate Cancer Prognosis

  • Esfahani, Maryam;Ataei, Negar;Panjehpour, Mojtaba
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.7
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    • pp.2601-2611
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    • 2015
  • Prostate cancer, with a lifetime prevalence of one in six men, is the second cause of malignancy-related death and the most prevalent cancer in men in many countries. Nowadays, prostate cancer diagnosis is often based on the use of biomarkers, especially prostate-specific antigen (PSA) which can result in enhanced detection at earlier stage and decreasing in the number of metastatic patients. However, because of the low specificity of PSA, unnecessary biopsies and mistaken diagnoses frequently occur. Prostate cancer has various features so prognosis following diagnosis is greatly variable. There is a requirement for new prognostic biomarkers, particularly to differentiate between inactive and aggressive forms of disease, to improve clinical management of prostate cancer. Research continues into finding additional markers that may allow this goal to be attained. We here selected a group of candidate biomarkers including PSA, PSA velocity, percentage free PSA, $TGF{\beta}1$, AMACR, chromogranin A, IL-6, IGFBPs, PSCA, biomarkers related to cell cycle regulation, apoptosis, PTEN, androgen receptor, cellular adhesion and angiogenesis, and also prognostic biomarkers with Genomic tests for discussion. This provides an outline of biomarkers that are presently of prognostic interest in prostate cancer investigation.

Factors Affecting Survival Time of Cholangiocarcinoma Patients: A Prospective Study in Northeast Thailand

  • Woradet, Somkiattiyos;Promthet, Supannee;Songserm, Nopparat;Parkin, Donald Maxwell
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.3
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    • pp.1623-1627
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    • 2013
  • Cholangiocarcinoma (CCA) is a major health problem and cause of death among people in Northeastern Thailand. In this prospective study 171 patients newly diagnosed with CCA by physicians in 5 tertiary hospitals in four provinces of northeastern of Thailand between February and July 2011 were followed up to January 2012. The outcome was survival time from diagnosis to death. A total of 758.4 person-months of follow-up were available. The mortality rate was 16.9 per 100 person-months (95%CI: 14.1-20.1). The median survival time among CCA patients was 4.3 months (95%CI: 3.3-5.1). Cox's proportional hazard model was used to study the independent effects of factors affecting survival time among patients. Statistically significant factors included advanced stage at diagnosis (HR: 2.5, 95%CI: 1.7-3.8), presentation with jaundice (HR: 1.7, 95%CI: 1.1-2.4) or ascites (HR: 2.8, 95%CI: 1.8-4.4), and positive serum carcinoembryonic antigen (HR: 2.3, 95%CI: 1.2-4.3). Patients who had received standard treatment had a better prognosis that those who did not (HR: 0.5, 95%CI: 0.3-0.7).