• Clinical and Experimental Pediatrics
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• 제54권4호
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• pp.176-178
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• 2011

Hemolytic-uremic syndrome (HUS) is the most common cause of acute renal failure in young children. It is classically characterized by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and uremia. Further, not only is intussusception one of the differential diagnoses of HUS but it may also become a complication during disease progression. We report a case of HUS. preceded by intussusception in a previously healthy 17-month-old boy. The patient presented at the emergency department with bloody stools that developed the day after reduction of intussusception. HUS was diagnosed 4 days after the reduction of intussusception. The patient was provided only supportive care and his laboratory test findings were normal at discharge.

• 대한기계학회논문집A
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• 제23권7호
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• pp.1094-1103
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• 1999

Ice-plugging of tube in nuclear power plant has been widely used for the purpose of preventing flow of the tube temporarily like a valve. Most common plugging method employs Liquid Nitrogen Gas of $-196^{\circ}C$. According to the change of tube materials and its dimension, the thermal stress caused from the application of the frozen gas can be varied. In this research, a series of experiments have been carried out to inspect the effect of tube geometry on thermal stresses induced due to ice-plugging. Two typical dimension of stainless and mild steels of 3 and 6 inch diameters were used for the experiments. Each critical spots were checked using strain rosette gages. Another inspection was made on the pressure and temperature of the fluid. It is shown that significant thermal stress level which can cause plastic deformation of failure has not been noticed in this series of experiments.

• 항공우주시스템공학회지
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• 제6권3호
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• pp.7-12
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• 2012

The contents of aircraft system safety assessment vary depending on factors such as the complexity of the system, how critical the system is to flight safety, what volume of experience is available on the type of system and the novelty and complexity of the technologies being used. If the system safety assessment is to substantiate that the developed products are 'safe enough' to be taken into use, then the system safety assessment should be planned and managed to provide the necessary assurance that all relevant hazards and failure conditions have been identified and that all significant combinations of hazards and failures which could cause those conditions have been considered. The assessment must assist the designer and management in making decisions. It must make clear what the critical features of each system are and upon which special manufacturing techniques, inspection, testing, crew drills and maintenance practice they are critically dependent. This paper has prepared to study on promoting the efficiency of aircraft system safety assessment and to present how to compile system safety assessment strategy.

• Journal of Chest Surgery
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• 제25권11호
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• pp.1346-1353
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• 1992

From Febrary 1984 to July 1992, 138 cases of multiple valve replacements were performed at the Department of Thoracic and Cardiovascular Surgery, Dongsan Medical Center, Keimyung University. There were 81 females and 57 males, and their ages ranged from 19 to 60 years [mean age, 40.1$\pm$10.9 years]. Thirteen of these patients had undergone previous cardiovascular procedures, with an average of 76.3 months between procedures[range, 3 to 180 months]. Mitral and aortic valve replacement were done in 135 patients, 2 underwent triple valve replacement and 1 underwent mitral and tricuspid valve replacement. Associated procedures were necessary in 20 patients[14.5%]. The operative mortality was 5.8% and the most common cause was low cardiac output. Late follow-up of 83% has been accomplished in 130 early survivors, with a late mortality of 5.9%. The late mortality was due to valve thrombosis in 2 patients, cerebral infarction in 1, heart failure in 1, arrhythmia in 1, and bleeding in l. Of those patients who survived, New York Heart Association functional class improved significantly[from 70% class III and IV before to 88% class I and II after]. Actuarial survival rate including all deaths was 88.8% at 8 years. The follow-up studies revealed that thromboembolism, reoperation and bleeding rate were 1.2%/patient-year, 0.85% /patient-year and 0.57%/patient-year at 8 years postoperatively. We concluded that valve thrombosis, embolism, and anticoagulant-related hemorrhage were the main risk factors of longterm survival of patients.

• Journal of Advanced Marine Engineering and Technology
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• 제40권2호
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• pp.131-137
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• 2016

In reliability analysis, it is quite common for the failure of any individual or item to be attributable to more than one cause. Moreover, observed data are often censored. Recently, progressive hybrid censoring schemes have become quite popular in life-testing problems and reliability analysis. However, a limitation of the progressive hybrid censoring scheme is that it cannot be applied when few failures occur before time T. Therefore, generalized progressive hybrid censoring schemes have been introduced. In this article, we derive the likelihood inference of the unknown parameters under the assumptions that the lifetime distributions of different causes are independent and exponentially distributed. We obtain the maximum likelihood estimators of the unknown parameters in exact forms. Asymptotic confidence intervals are also proposed. Bayes estimates and credible intervals of the unknown parameters are obtained under the assumption of gamma priors on the unknown parameters. Different methods are compared using Monte Carlo simulations. One real data set is analyzed for illustrative purposes.

• 말소리와 음성과학
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• 제7권2호
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• pp.55-62
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• 2015

It is widely accepted that Parkinson's disease(PD) is the most common cause of hypokinetic dysarthria, and its characteristics of 'short rushes of speech' have become more evident along with the severity of motor disorders. Speech alternate motion rates (AMRs) are particularly useful for observing not only rate abnormalities but also deviant speech. However, relatively little is known about the characteristics of 'short rushes of speech' in terms of AMRs of PD except for the perceptual characteristics. The purpose of this study was to examine which acoustic features of 'short rushes of speech' in terms of AMRs are a robust indicator of Parkinsonian speech. Numbers of syllabic repetitions (/pə/, /tə/, /kə/) in AMR tasks were analyzed through acoustic methods observing a spectrogram of the Computerized Speech Lab in 9 patients with PD. Acoustically, we found three characteristics of 'short rushes of speech': 1) Vocalized consonants without closure duration(VC) 76.3%; 2) No consonant segmentation(NC) 18.6%; 3) No vowel formant frequency(NV) 5.1%. Based on these results, 'short rushes of speech' may affect the failure to reach and maintain the phonatory targets. In order to best achieve the therapeutic goals, and to make the treatment most efficacious, it is important to incorporate training methods which are based on both phonation and articulation.

• 전기기술인
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• 제228권8호
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• pp.43-48
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• 2001

우리나라에서는 3 Θ 4w 배전방식을 채택하고 있는데 최근에는 컴퓨터 등 OA 기기 사용증가로 이때 발생하는 영상분 고조파에 의하여 중성선에 상전류 보다 큰 전류가 흐르게 된다. 고조파에 의한 중전선 과전류는 케이블, 변압기, 과열소손, 변압기, 발전기 출력저하, 역률저하, 전력손실 증가, ELB, MCCB 오동작, 유도장해, 중성선 대지전위 상승 등 심각한 장애를 일으키고 있다.

• 한국기계가공학회지
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• 제17권1호
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• pp.144-152
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• 2018

The cleanability of machine parts is becoming increasingly important in the industrial field. In particular, cleanability is the most important factor in hydraulic products. The burr and chips are dominant factors of cleanability. If the burrs are not removed completely before the beginning of the machining stage, this will cause many problems, such as scratches and operation failure. Due to the complexity of the valve body itself, it is very difficult to use common deburring tools. In this study, a brush-like deburring tool was suggested and verified as a proper tool for removing the burrs and forming a proper edge shape through a real experiment. Various kinds of brush materials and process conditions were tested for proper deburring of the valve body. It was shown that the suggested method was successful for valve body deburring.

• 대한기관식도과학회지
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• 제4권2호
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• pp.188-192
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• 1998

Background and Objectives： The most common cause of the failure of endoscopic dacryocystorhinostomy is closure of the osteotomy site due to granulation or adhesion. We used mitomycin-C, an antineoplastic antibiotic agent, soaking over the osteotomy site to suppress fibrous proliferation and scar formation during the endoscopic dacryocystorhinostomy. Materials and Methods : A total of 20 Patients diagnosed with nasolacrimal duct obstruction were assigned randomly to either a mitomycin-C group or a control group. Endoscopic dacryocystochinostnmy has been used in both groups. In the mitomycin-C group, a piece of merocel soaked with 0.2 mg/ml mitomycin-C was applied to the osteotomy site and then after 30 minutes was removed. Results : All patients in the mitomycin-C group remained symptom free after removal of their silicone tube (100% success), and there were two patients in the control group who had recurrent epiphora (67% success). In the mitomycin-C group, the average surface area of the osteotomy at the end of the sixth postoperative month was 4.1 $\textrm{mm}^2$, whereas that of the control group was 2.5 $\textrm{mm}^2$. Neither serious systemic nor local toxicity were noted in the mitomycin-C group. Conclusion : Intraoperative mitomycin-C may possibly improve success rates over the endoscopic dacryocystorhinostomy procedure.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권4호
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• pp.775-787
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• 2014

Availabilities of subsea Blowout Preventers (BOP) in the Gulf of Mexico Outer Continental Shelf (GoM OCS) is investigated using a Markov method. An updated ${\beta}$ factor model by SINTEF is used for common-cause failures in multiple redundant systems. Coefficient values of failure rates for the Markov model are derived using the ${\beta}$ factor model of the PDS (reliability of computer-based safety systems, Norwegian acronym) method. The blind shear ram preventer system of the subsea BOP components considers a demand rate to reflect reality more. Markov models considering the demand rate for one or two components are introduced. Two data sets are compared at the GoM OCS. The results show that three or four pipe ram preventers give similar availabilities, but redundant blind shear ram preventers or annular preventers enhance the availability of the subsea BOP. Also control systems (PODs) and connectors are contributable components to improve the availability of the subsea BOPs based on sensitivity analysis.