• Plant Journal
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• v.8 no.3
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• pp.49-54
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• 2012

In this study, the way how we can find the defects of motor windings in advance will be discussed. The magnetic flux spectrum in the high frequency region of the large motor was analyzed based on the actual fault practices related with motor windings. In case of defective motor relative amplitude ratio of the stator slot frequency to its sideband was very high compared to that of healthy motor. And the defective signal related with motor windings was indicated in advance in the magnetic flux spectrum prior to over 1 month before failure. Considering this aspect it can be estimated that magnetic flux spectrum in the high frequency region has the excellent predictive diagnostic capability.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.3
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• pp.555-561
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• 1998

Hypophosphatasia is a rare metabolic disorder which manifests characteristics such as abnormal mineralization of bone and dental tissues, diminished serum and tissue alkaline phosphatase, and increased urinary secretion of PEA. It inherited as an autosomal recessive or dominant trait and occurs in all races. In general, hypophosphatasia can be classified in 4 subtypes which are the perinatal, infantile, childhood, adult type depending upon the age at presentation and severity. In young children with Hypophosphatasia the long bones show irregular defects, and the skull showes poor calcification. In older children with premature closure of the skull sutures there may be multiple lucent area called gyral or convolutional markings, described as resembling beaten copper, presumably resulting from increased intracranial pressure. Examination of the jaws reveals a generalized lucency of the maxilla and mandible. the cortical bone and lamina dura are thin, and the alveolar bone may be deficient. Clinical features of Hypophosphatasia include premature loss of deciduous teeth, especially incisors, hypoplasia or aplasia of root cementum, enamel hypoplasia, irregular calcification of dentin, large pulp chamber, and resorption of marginal alveolar bone and roots. Our report involves a patient with a chief complaint of early loss of both Mx. and Mn. deciduous incisors. After conducting a through clinical and radiographic examination this patient was referred to pediatrics under the suspicion of hypophosphatasia, the diagnosis proved to be correct and successful results were accomplished through a denture made to improve esthetics and function.

• Clinical and Experimental Reproductive Medicine
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• v.38 no.2
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• pp.115-118
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• 2011

A 58-year-old woman who presented with inguinal hernia for the first time was diagnosed as seminoma and complete androgen insensitivity syndrome (CAIS). The patient received a late diagnosis, and therefore she could not take a proper management. CAIS is a rare X-linked recessive disease with an XY karyotype that is caused by androgen receptor defects. It usually present with primary amenorrhea or inguinal hernia. The risk of malignant transformation of undescended testis increases with age, thus gonadectomy should be performed after puberty. We present a case of large advanced seminoma in a woman with CAIS who was neglected and diagnosed lately.

• Journal of Genetic Medicine
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• v.13 no.2
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• pp.99-104
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• 2016

$Cant{\acute{u}}$ syndrome (CS, OMIM 239850) is a very rare autosomal dominantly inherited genetic disease characterized by congenital hypertrichosis, neonatal macrosomia, a distinct facial features such as macrocephaly, and cardiac defects. Since the first description by $Cant{\acute{u}}$ et al. in 1982, about 50 cases have been reported to date. Recently, two causative genes for CS has been found by using exome sequencing analyses: ABCC9 and KCNJ8. Most cases of clinically diagnosed CS have resulted from de novo mutations in ABCC9. In this study, we report three independent Korean children with CS resulting from de novo ABCC9 mutations. Our patients had common clinical findings such as congenital hypertrichosis, distinctive facial features. One of them showed severe pulmonary hypertension and hypertrophic cardiomyopathy, which require medical treatment. And, two patients had a history of patent ductus arteriosus. Although two of our patients had shown early motor developmental delay, it was gradually improved during follow-up periods. Although CS is quite rare, there are the concerns about development of various cardiac problems in the lifetime. Therefore, an accurate diagnosis followed by appropriate management and genetic counseling should be provided to CS patients.

• Journal of Electrical Engineering and Technology
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• v.9 no.5
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• pp.1686-1693
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• 2014

In this paper, oil-paper samples composed of transformer windings were used to investigate the insulation degradation process subjected to partial discharge (PD), with artificial defects inside to simulate the PD induced insulation degradation. To determine appropriate test voltages, the breakdown time obtained through a group of accelerated electrical degradation tests under high voltages was firstly fitted by two-parameter Weibull model to acquire the average breakdown time, which was then applied to establish the inverse power law life model to choose advisable test voltages. During the electrical degradation process, PD signals were synchronously detected by an ultra-high frequency (UHF) sensor from inception to breakdown. For PD analysis, the whole degradation process was divided into ten stages, and chaos theory was introduced to analyze the variation of three chaotic parameters with the development of electrical degradation, namely the largest Lyapunov exponent, correlation dimension and Komogorov entropy of PD amplitude time series. It is shown that deterministic chaos of PD is confirmed during the oil-paper degradation process, and the obtained results provide a new effective tool for the diagnosis of degradation of oil-paper insulation subjected to PD.

• Tribology and Lubricants
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• v.31 no.2
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• pp.35-41
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• 2015

A water-pump located in the cooling area of a car circulates cooling water. A particular bearing element, known as a water-pump bearing, installed in the rotating part carries the entire load. The failure of this water-pump bearing has a direct impact on the failure of the automobile engine, and so securing its reliability is crucial. Several researchers have examined the design principles of the water-pump bearing, but there are no reports on the life characteristic of the bearing yet. Herein, we report the construction of test equipment to reproduce the spalling of the roller contact, which is the main failure mode of the chosen water-pump bearing. We chose the radial load as an accelerated stress factor and validated the failure mode by monitoring the surface defects. We conducted the accelerated life test after determining the accelerated stress level through a combination of finite element analysis and a preliminary test. In the life tests, we used an accelerometer to perform failure diagnosis. In the last stage of this study, we present a statistical reliability analysis. Thus, we fully estimated the shape parameter of the water-pump bearing, accelerating level on the load , and the lifetime (MTTF and B₁₀ life) under real use conditions, and finally proposed an interval estimation value considering the uncertainty of the estimated value.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.2 no.2
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• pp.262-266
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• 1999

Obstruction of the extrahepatic bile ducts is the most common cause of conjugated hyperbilirubinemia in early infancy. More than 90% of such obstructive lesions are accounted for by extrahepatic biliary atresia. A rare lesion is obstruction of the common duct by impacted, thickened secretions and bile. Bile plug syndrome is defined as extrahepatic obstruction of the bile ducts by bile sludge in term infants without anatomic abnormalities, congenital chemical defects of bile, or hepatocellular lesions. Obstruction of extrahepatic ducts by plugs of biliary material apperas to be due to the inspissation and precipitation of bile and mucus within the lumen of the ducts. Cholestasis and precipitation of bile develop in association with abnormal composition of bile in cystic fibrosis, hepatocellular damage, prolonged erythroblastic jaundice, altered biliary dynamics with total parenteral nutrition, gut dysfunction, diuretic therapy, exchange transfusions and perinatal hemolysis. In those cases, the term inspissated bile syndrome is used. The clinical and laboratory findings in bile plug syndrome are identical to those observed in biliary atresia and choledochal cyst. The diagnosis can be suspected based on the findings of clinical and laboratory examinations together with hepatobiliary imaging, ultrasonography, radionuclide scan and liver biopsy. We experienced a case of spontaneous resolution of bile plug syndrome in a 4-year-old girl. We report this case with brief review related literatures.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.1
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• pp.53-59
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• 2016

Ultrasonic nonlinear evaluation is generally utilized for detection of not only defects but also microdamage such as corrosion and plastic deformation. Nonlinearity is determined by the amplitude ratio of primary wave second harmonic wave, and the results of its comparison are used for evaluation. Owing to the experimental features, the experimental nonlinearity result contains system nonlinearity and material nonlinearity. System nonlinearity is that which is unwanted by the user; hence, it acts as an error and interrupts analysis. In this study, a bulk wave mixing technique is implemented in order to minimize the system nonlinearity and obtain the reliable analysis results. The biggest advantage of this technique is that experimental nonlinearity contains less system nonlinearity than that for the conventional nonlinear ultrasonic technique. Theoretical and experimental verifications are performed in this study. By comparing the results of the bulk wave mixing technique with those of the conventional technique, the strengths, weaknesses, and application validity of the bulk wave mixing technique are determined.

• Archives of Craniofacial Surgery
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• v.22 no.5
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• pp.268-275
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• 2021

Background: The study aimed to evaluate nasal reconstruction techniques customized for Asians. The currently available nasal reconstruction guidelines are based on Caucasian patients, and their applicability is limited in Asian patients due to differences in anatomical and structural features. Methods: A retrospective analysis was performed of the medical records of 76 patients who underwent nasal reconstruction at a single center between January 2010 and June 2020. A comprehensive evaluation was conducted of patients' baseline demographics and clinical characteristics, including age, sex, medical history, defect size and location, reconstructive procedure, pathological diagnosis, postoperative complications, and recurrence. Results: In 59 cases (77%), nasal defects resulted from tumor ablation, and the remaining 17 cases involved post-traumatic (20%) and infection-induced (3%) tissue damage. The most common defect location was the alae, followed by the sidewalls, tip, and dorsum. Forehead flaps were the most commonly used reconstructive technique, followed by nasolabial advancement flaps, rotation flaps, and skin grafts. Each procedure was applied considering aspects of structural anatomy and healing physiology specific to Asians. Complications included nasal deformity, hypertrophic scarring, secondary infection, and partial flap necrosis, but no cases required additional surgical procedures. Tumors recurred in two cases, but tumor recurrence did not significantly affect flap integrity. Conclusion: Nasal reconstruction techniques applied considering Asians' facial features resulted in fewer postoperative complications and higher patient satisfaction than the approaches that are currently in widespread use. Therefore, this study is expected to serve as an essential reference for establishing treatment guidelines for nasal reconstruction in Asians.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.4
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• pp.382-394
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• 2022

The treatment of patients with severe periodontitis should be proceeded step-bystep through an accurate diagnosis of each patients' individual tooth and with a strategic treatment plan. Implant-supported fixed prosthetic restoration has the advantage of high patient satisfaction and stable vertical dimension compared to the removable partial denture. However, multiple teeth defect areas lacking hard tissue may be disadvantageous in aesthetic failure and longer treatment time. In addition, it takes a certain period of time to manufacture and install a conventional fixed prosthesis, and during this process, the provisional prosthesis must satisfy the mechanical, biological, and aesthetic requirements of teeth. The purpose of this article is to describe the fabrication of implant-supported fixed prosthesis through a step-by-step approach in a partially edentulous patient.