• Wind and Structures
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• v.25 no.1
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• pp.79-100
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• 2017

The use of wind energy resources is developing rapidly in recent decades. There is an increasing number of wind farms in high wind-velocity areas such as the Pacific Rim regions. Wind turbine towers are vulnerable to tropical cyclones and tower failures have been reported in an increasing number in these regions. Existing post-disaster failure case studies were mostly performed through forensic investigations and there are few numerical studies that address the collapse mode simulation of wind turbine towers under strong wind loads. In this paper, the wind-induced failure analysis of a conventional 65 m hub high 1.5-MW wind turbine was carried out by means of nonlinear response time-history analyses in a detailed finite element model of the structure. The wind loading was generated based on the wind field parameters adapted from the cyclone boundary layer flow. The analysis results indicate that this particular tower fails due to the formation of a full-section plastic hinge at locations that are consistent with those reported from field investigations, which suggests the validity of the proposed numerical analysis in the assessment of the performance of wind-farms under cyclonic winds. Furthermore, the numerical simulation allows to distinguish different failure stages before the dynamic collapse occurs in the proposed wind turbine tower, opening the door to future research on the control of these intermediate collapse phases.

• Journal of Korean Society for Quality Management
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• v.51 no.4
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• pp.551-571
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• 2023

Purpose: The purpose of this study is to propose useful suggestions by analyzing the causal effect relationship between the failure rate of quality and the process variables in the C5ISR domain of the defense industry. Methods: The collected data through the in house Systems were analyzed using Big data analysis. Data analysis between quality data and A/S history data was conducted using the CRISP-DM(Cross-Industry Standard Process for Data Mining) analysis process. Results: The results of this study are as follows: After evaluating the performance of candidate models for the influence of inspection data and A/S history data, logistic regression was selected as the final model because it performed relatively well compared to the decision tree with an accuracy of 82%/67% and an AUC of 0.66/0.57. Based on this model, we estimated the coefficients using 'R', a data analysis tool, and found that a specific variable(continuous maximum discharge current time) had a statistically significant effect on the A/S quality failure rate and it was analysed that 82% of the failure rate could be predicted. Conclusion: As the first case of applying big data analysis to quality issues in the defense industry, this study confirms that it is possible to improve the market failure rates of defense products by focusing on the measured values of the main causes of failures derived through the big data analysis process, and identifies improvements, such as the number of data samples and data collection limitations, to be addressed in subsequent studies for a more reliable analysis model.

• Clinical and Experimental Reproductive Medicine
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• v.43 no.3
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• pp.181-184
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• 2016

The aim was to report a healthy live birth using re-vitrified-warmed cleavage-stage embryos derived from supernumerary warmed embryos after frozen embryo transfer (ET) in a patient with recurrent implantation failure (RIF). The case was a 39-year-old female with a history of polycystic ovarian syndrome and adenomyosis, along with RIF. After ovarian hyperstimulation, 33 cumulus-oocyte complexes were retrieved and fertilized with conventional in vitro fertilization and intracytoplasmic sperm injection. Because of the risk of ovarian hyperstimulation syndrome, 16 grade B and C embryos were vitrified. After 3 and 6 months, 3 and 4 B-C warmed embryos were transferred to the uterus, respectively. However, implantation did not take place. Ten months later, four embryos were warmed, two grade B 8-cell embryos were transferred, and two embryos were re-vitrified. One year later, the two re-vitrified cleavage-stage embryos were warmed, which resulted in a successful live birth. This finding showed that following first warming, it is feasible to refreeze supernumerary warmed embryos for subsequent ET in patients with a history of RIF.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.28 no.1
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• pp.285-297
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• 1998

This report details a case of 8-year-old girl showing failure of odontogenesis after chemo-radiation therapy for the rhabdomyosarcoma at the age of 4. The observed results were as follows : 1. Past history revealed that she had received for a total radiation dose of 4430cGy, 29 fractions in 6 weeks and chemotherapy with vincristine, actinomycin D and cytoxan, followed as maintenance phase for 2 years. 2. The patient was symptom -free and appointed for the treatment of multiple dental caries. 3. Oral examination showed hypoplastic enamel on whole erupted permanent teeth and showed retarded eruption. 4. Conventional radiograms showed failure of root development including abrupt cessation of root formation and root agenesis, and microdontia, missing teeth, irregular enamel, dislocation of the impacted teeth. Additional finding showed good healing bone pattern on the left mandibular ramus and angle area. 5. Cephalometric analysis revealed failure of bite raising due to incomplete eruption of all the first molars and made it possible to suspect entrapped mandibular growth and then Class II tendency growth. 6. There was correlation between the time of chemo-radiation therapy and the damage of the teeth.

• Journal of Veterinary Clinics
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• v.19 no.1
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• pp.103-106
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• 2002

Specific diagnosis of orthopedic disease can be diffcult in canine practice. Failure to detect the clinical signs of a disorder during physical examination of dogs with acute or chronic lameness is the most common reason for failure to make specific diagnosis. A 6-month-old, female doberman with history of swelling and non-weight-bearing lameness in the left forelimb was referred to Beterinary Teaching Hospital of Chungbuk National University. Physical examination, plain radiography, and conventional three-phase radionuclide bone scan were performed in the patient. Based on the physical exam and radiography, this case was diagnosed as elbow strain and subluxation. Conventional three-phase bone scan detected soft tissue inflammation and osteochondral lesions of elbow joint, and revealed good agreement with clinical findings. Therefore, conventional three-phase bone scan was able to provide the precise information about inflammation of soft tissue and osteochondral lesions of joint.

• Journal of The Korean Society of Clinical Toxicology
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• v.6 no.2
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• pp.110-116
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• 2008

Purpose: Acute toxic hepatitis is a common cause of acute liver failure (ALF). We investigated the causes, clinical manifestation, and outcomes of ALF patients who underwent liver transplantation due to acute toxic hepatitis caused by herbal medicines and preparations. Methods: Between January 1992 and May 2008, we retrospectively reviewed the medical records of 24 patients who were transplanted due to acute toxic hepatitis caused by herbal medicines and preparations. We applied the RUCAM score to patients with acute toxic hepatitis and assessed the relationship between herbal preparations and liver injury. We studied the patients' medication history, liver function tests, and clinical outcomes. Results: The type of liver injury was divided into three groups: hepatocellular type, 14 patients (58.3%); cholestatic type, 4 patients (16.7%); and mixed type, 6 patients (25%). Polygonum multiflorum Thunberg (3 cases) was the most common cause of acute toxic hepatitis, followed by Acanthopanax senticosus (2 cases), pumpkin juice (2 cases), Dictamnus dasycarpus Turcz (2 cases), Hovenia dulcis (1 case), Phellinus linteus (1 case), and Artemisia capillaries (1 case). One year survival after liver transplantation was 76%. Conclusion: We identified the herbal preparations leading to acute liver failure. Many patients consider herbal remedies to be completely free of unwanted side effects. However, we found that many herbal products have biological activities that can lead to severe hepatotoxicity.

• Pediatric Infection and Vaccine
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• v.13 no.2
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• pp.201-205
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• 2006

Immunodeficiency affected by antibody formation is most common among primary immuno-deficiencies. Selective IgA deficiency is more common but, one or more IgG subclass level is low or deficient in some patients. Patients with antibody production deficiency are vulnerable to pneumococci, staphylococci and H.influenzae leading to sinusitis, otitis media and pneumonia. A 10-year-old girl had suffered from frequent upper respiratory infections, a history of tuberculous lymphadenitis tuberculosis medication, and frequent pneumonia that requires hospital adimission. Her height and weight were below 3 percentile normal growth as a manifestation of failure to thrive. When she had another severe pneumonia, all the immunologic test was normal at first, and then we checked the IgG subclass levels. Her IgG1 was within normal, IgG2 was very low, IgG3 and IgG4 was not detected. We report a case of IgG subclass deficiency in frequent upper respiratory infection and failure to thrive.

• Tunnel and Underground Space
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• v.18 no.4
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• pp.289-299
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• 2008

Based on the case study on the causes for the failure of cutting slope composed of weathered rock and soil, the factors influencing the design of a cutting slope have been examined, This type of rock and soil is widely distributed on the region whose parent rock is granite. To analyze the stability of the cutting slope, the following series of progress has been conducted: (1) ground characterization by geological survey and ground investigation, (2) the safety factor examination by limit equilibrium analysis and numerical analysis and (3) the comparison and analysis of rainfall and failure history. As a result, the main factors to cause the failure is determined to be the decrease of shear strength in the upper parts whose ground condition is weakened during localized heavy rain. Moreover, the analysis indicates the failure is also closely related to the groundwater inflow path. On the base of this investigation, a reinforcement method is proposed to ensure the stability of the cutting slope.

• Journal of Veterinary Clinics
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• v.41 no.2
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• pp.106-111
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• 2024

A 4-year-old neutered female domestic shorthair cat weighing 5.1 kg was referred to Jeju National University Hospital with acute onset respiratory distress, weakness, and anorexia. The patient had a history of stressful antecedent events that involved bullying by a newly introduced cat. Thoracic radiography and echocardiography revealed a stage C hypertrophic cardiomyopathy phenotype based on the American College of Veterinary Internal Medicine classification system with pulmonary edema, pleural effusion, and pericardial effusion at the same time. The patient was treated with furosemide, pimobendan, and rivaroxaban. Pericardiocentesis was performed because pericardial effusion was identified. Reevaluation after 30 days revealed a normal respiratory rate on physical examination, normal cardiac shape on thoracic radiographs, and normal cardiac measurements on echocardiography. The patient was tentatively diagnosed with transient myocardial thickening (TMT) and all medications were discontinued. Six months after the initial hospitalization, the cat continued to do well without any clinical signs or left ventricular wall thickening. This case is the first report describing feline TMT in Korea. Moreover, it involves a rare case in which pulmonary edema, pleural effusion, and pericardial effusion, which induce cardiac tamponade, occurred simultaneously due to TMT-related congestive heart failure.

• The Korean Journal of Quaternary Research
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• v.18 no.1 s.22
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• pp.31-39
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• 2004

The stable-unstable curve graph (S-U curve) and the ignition los curve graph (IL curve) for pollen composition and inorganic material content in three areas (namely, Kawadoi Basin, Moniwa-Takada moor, and Nenoshiroishi moor) were prepared to reconstruct the recurrence history of slope failure during the Holocene in Northeastern Japan. Through the S-U curve, a period with a high slope failure frequency of 5,600~4,670yrB.P. was identified in Kawadoi Basin, two of 6,390~5,070yrB.P. and 4,750~3,800yrB.P. in Moniwa-Takada moor, and three of 6,630~6,070yrB.P., 5,890~5,360yrB.P., and 5,000~4,650yrB.P. in Nenoshiroishi moor. Through the IL curve, a period with a high slope failure frequency of 5,600~5,140yrB.P. was identified in Kawadoi Basin, and two of 6,390~6,170yrB.P. and 4,750~2,840yrB.P. in Moniwa-Takada moor. Most of above-mentioned periods were included in the period of slope instability in precedent studies. However, the periods with high slope failure frequency in this study were rather different from those in precedent studies. The times and numbers associated with these periods in each study area also showed discrepancies. Accordingly, to achieve the above-mentioned purpose, more case studies must be performed to improve the reconstruction level of slope failure frequency, which could be explained through the analysis of pollen composition and inorganic material content.