• 한국안전학회지
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• 제35권3호
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• pp.86-95
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• 2020

This paper describes the work and the results of the final Probabilistic Safety Assessment (PSA) for the Jordan Research and Training Reactor (JRTR). This final PSA was undertaken to assess the level of safety for the design of a research reactor and to evaluate whether it is probabilistically safe to operate and reliable to use. The scope of the PSA described here is a Level 1 PSA, which addresses the risks associated with core damage. After reviewing the documents and its conceptual design, nine typical initiating events were selected regarding internal events during the normal operation of the reactor. AIMS-PSA (Version 1.2c) was used for the accident quantification, and FTREX was used as the quantification engine. 1.0E-15/yr of the cutoff value was used to deliminate the non-effective Minimal Cut Sets (MCSs) when quantifying the JRTR PSA model. As a result, the final result indicates a point estimate of 2.02E-07/yr for the overall Core Damage Frequency (CDF) attributable to internal initiating events in the core damage state for the JRTR. A Loss of Primary Cooling System Flow (LOPCS) is the dominant contributor to the total CDF by a single initiating event (9.96E-08/yr), and provides 49.4% of the CDF. General Transients (GTRNs) are the second largest contributor, and provide 32.9% (6.65E-08/yr) of the CDF.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2008년도 정기 학술대회
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• pp.387-390
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• 2008

The importance of the life cycle cost analysis for construction projects of bridge has been recognized over the last decades. Accordingly, theoretical models, guidelines, and supporting softwares have been developed for the life cycle cost analysis of bridges. However, it is difficult to predict life cycle cost considering uncertainties precisely. This paper presents methodology for optimal design of substructure for a steel box bridge. Total life cycle cost for the service life is calculated as sum of initial cost, damage cost considering uncertainty, maintenance cost, repair and rehabilitation cost. The optimization method is applied to design of a bridge substructure with minimal cost, in which the objective function is set to life cycle cost and constraints are formulated on the basis of Korean Bridge Design Specification. Initial cost is calculated based on standard costs of the Korea Construction Price Index and damage cost on the damage probabilities to consider the uncertainty of load and resistance. An advanced first-order second moment method is used as a practical tool for reliability analysis using damage probability. Maintenance cost and cycle is determined by a stochastic method and user cost includes traffic operation costs and time delay costs.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권2호
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• pp.757-770
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• 2020

We propose a hand gesture recognition method that is compatible with a head-up display (HUD) including small processing resource. For fast link adaptation with HUD, it is necessary to rapidly process gesture recognition and send the minimum amount of driver hand gesture data from the wearable device. Therefore, we use a method that recognizes each hand gesture with an inertial measurement unit (IMU) sensor based on revised correlation matching. The method of gesture recognition is executed by calculating the correlation between every axis of the acquired data set. By classifying pre-defined gesture values and actions, the proposed method enables rapid recognition. Furthermore, we evaluate the performance of the algorithm, which can be implanted within wearable bands, requiring a minimal process load. The experimental results evaluated the feasibility and effectiveness of our decomposed correlation matching method. Furthermore, we tested the proposed algorithm to confirm the effectiveness of the system using pre-defined gestures of specific motions with a wearable platform device. The experimental results validated the feasibility and effectiveness of the proposed hand gesture recognition system. Despite being based on a very simple concept, the proposed algorithm showed good performance in recognition accuracy.

• 대한기계학회논문집
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• 제17권5호
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• pp.1183-1192
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• 1993

본 연구에서는 다음과 같은 두가지 관점에서 공구경로 최적화를 위한 기존 방 법의 문제점을 검토하고 이의 개선 방안을 제시하였다. 첫째, 기존의 공구경로 산출 방법에서는 고려되지 않는 공구대의 공구 장착 현황(turret configuration)이 최적화 과정에서 고려되어야 한다. 둘째로, 제작과 관련한 구속조건(manufacturing con- straints)이 최적화 과정에 직접 반영되어야 한다.

• 전력전자학회논문지
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• 제4권2호
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• pp.166-174
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• 1999

최적효율제어를 통한 유도전동기의 효율향상은 에너지 절감측면에서 매우 중요하며 인공신경망을 사용하면 시스템의 특성이 충분히 해석되지 않은 상태에서도 우수한 제어특성을 얻을 수 있다. 본 논문은 유도전동기 구동시스템에서 최적 슬립주파수를 추종하는 실시간 인공신경망 회로를 구성하여 운전효율을 최적화하는 제어방법을 제안한다. 제안된 최적 효율제어기는 인공신경망 제어기에 의해 시스템의 비선형성을 포함하여 전동기의 내부손실이 최소가 되는 운전점을 추종한다. 시뮬레이션과 실험을 통하여 기존의 일정v/f 방식에 비하여 고속 경부하시 경제성 있는 에너지 절감효과를 충분히 확보할 수 있었다.

• Journal of Biosystems Engineering
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• 제32권3호
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• pp.145-152
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• 2007

Uniformity of spray deposit is one of the important factors in spray performance affecting efficacy of pest management. Distributions of spray deposit on artificial targets were measured and analyzed to enhance the efficiency of spray application. The research was studied to understand the deposition characteristics of spray droplets and to determine the optimum conditions of chemical application. The deposit and its pattern by the lower fan speed was more uniform and higher than that by the higher fan speed. The upward blasting distance was limited within 3 m, but the limit to the ground level was expanded the distance more than 3.5 m because of the accumulated droplets. When the fan speed was higher at the distance of 2.5 m, deposit reached to maximum. When the distance increased, deposit was getting lower. At the both fan speeds, the deposit was concentrated below $30^{\circ}$ because of the gravitation and the resistance of wind. This research can be useful in designing an orchard sprayer and its operation for various tree canopies. To achieve a uniform distribution of deposit using the air-blast type orchard sprayer, the application rate from the middle boom should be increased as the air velocity to the upward increased. The spray rate to the side boom should be limited in a minimal level.

• 대한견주관절학회:학술대회논문집
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• 대한견주관절학회 2008년도 제16차 학술대회
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• pp.175-175
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• 2008

We report a rare case of late-onset brachial artery occlusion caused by subclavian artery stenosis with excessive scar tissue after open reduction and plate fixation for clavicular fracture. When he referred to us, the right hand were pale and the radial and ulnar pulses at the wrist were absent. CT-angiogram showed compression of subclavian artery by excessive scar tissue beneath the fracture site and angiography revealed stenosis of subclavian artery with thrombus and complete obstruction of blood flow in the brachial artery with emboli. Therefore, we performed embolectomy. 2 years after operation, patient was essentially asymptomatic except mild pain after long standing elevation of arm. We recommend that minimal soft tissue dissection should be needed in the operative treatment of clavicular fracture, especially soft tissue beneath the clavicle should be protected maximally.

• Journal of Chest Surgery
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• 제24권2호
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• pp.153-160
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• 1991

Tetralogy of Fallot was repaired by a transatrial-transpulmonary approach in 91 of 250 patients treated surgically [including redo operations] between April 1986 and December 1989. Their age ranged from 6 months to 14 years [mean 39.7 months]. Associated cardiovascular anomalies were right aortic arch [n=22], ASD [n=12], PDA [n=5], persistent left SVC [n=5], and others [n=6]. PA index was measured pre-operatively since 1987 to estimate pulmonary artery size and safe total correction[mean 289$\pm$110mm2/BSA]. Eight patients received previous shunt take down procedure concomitantly. Pulmonary arteriotomy was extended through small pulmonary annulus to a minimal distance upon the right ventricular infundibulum and transannular patch was applied in 38 patients [41.3%], in 31 of them monocuspid patch was utilized. pRV/LV was measured at operation room in 77 patients [mean 0.58$\pm$0.36]. Operative mortality was 6.6% [6/91]. The causes of death were low cardiac output [n=5], arrhythmia[n=1] and respiratory failure [n=1]. At follow-up between 12 months and 57 months [mean 30.8 months] most patients were in New York Heart Association class I without cardiac medication. There was no late death, but reoperations were required in 3 patients to relieve residual right ventricular outflow obstruction. Thus successful repair of tetralogy of Fallot can be accomplished in most patients including infants by transatrial-transpulmonary approach and the better result can be anticipated with respect to postoperative right ventricular function and arrhythmia than the conventional transventricular approach.

• Journal of Chest Surgery
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• 제7권2호
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• pp.139-144
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• 1974

Clinical observations were made on 513 cases of pulmonary resection for tuberculosis, those were treated at the Department of Thoracic Surgery in National Medical Center from January 1964 to December 1973. 1. The ratio of male to female cases of operation was 2.8:1 in male predominence and age from 21 to 30 occurred 74.3% of the total cases. 2. The extent of disease showed 59.3% moderately advanced, 38.4% far advanced and 2.3% minimal cases. Duration of chemotherapy before surgery was more than one year in 92.7% and only 7.3% was treated less than one year. Preoperative sputum examination for AFB was persistent negative in 8.6,% of cases. 3. Different operative procedures were performed in 513 cases, lobectomy in 230, pneumonectomy and Pleuropneumonectomy in 172, segmentectomy in 63, lobectomy and supplemental segmentectomy with conventional thoracoplasty in 32 cases. 4. The postoperative complications occurred in 67 cases [13.0%]. Of these complications, bleeding in 4.6% , dead space problem in 2.5% and empyema with or without bronchopleural fistula occurred in 2.3% of cases. 5. Overall mortality within 5 months postoperative period was 1.5,0/0 and the most common causes of death were due to shock and empyema with bronchopleural fistula. 6. In all our 867 cases of report I and II, complications occurred in 13.9% and mortality rate was 1.8%.

• Journal of Korean Neurosurgical Society
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• 제43권4호
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• pp.194-197
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• 2008

Primary cerebellar glioblastoma multiforme (GBM) is a rare tumor in adults that accounts for just 1% of all cases of GBM. Due to their rarity, cerebellar GBMs are not yet completely understood about the pathogenesis and the prognosis. Here, we present a case of GBM in a 69-year-old man. Neurologic examination revealed the presence of cerebellar signs. Magnetic resonance imaging (MRI) showed a 4.5${\times}$3.6 cm-sized, ill-defined, heterogeneously enhancing mass in the left cerebellum and two patchy hyperintense lesions in the right cerebellum with minimal enhancement. After operation, glioblastoma was histologically confrimed. Postoperative radiotherapy with concomittent and adjuvant temozolomide chemotherapy was subsequently followed. Here, a case of unusual GBM in the cerebellum is reported with review of literature regarding the pathogenesis, the differential diagnosis and prognosis. There was no evidence of recurrence during postoperative one year. This patient showed a good prognosis in spite of the multiple lesions.