• Journal of Practical Engineering Education
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• v.8 no.2
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• pp.103-109
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• 2016

In order to get the maintenance work for the normal operation of rail vehicles made safe maintenance training, which looked suffered direct physical train maintenance environment, gain experience to get out foster the practical skills, but experience the real maintenance in operational problems the maintenance procedures followed are difficult to be. So it can gain experience and knowledge of the actual maintenance work in safe conditions if you apply a simulation experience in a similar environment as possible to the actual train maintenance training can also reduce operational training costs. For a description of the current domestic and simulation programs of the railway sector it has been operating in overseas and is designed to train intensive training, maintenance and maintenance-related information is scarce situation. In this study, the contents of the theory of educational technology for effective training of train maintenance elements exhibit theory, theory of learning situations, designed to train maintenance training simulation through a previous study that investigated the problem-based learning theory.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.2
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• pp.18-25
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• 2016

Bascule bridge, with its use to help vessels ply, has a several examples overseas of being serviced for more than decades years by careful maintenance, admitted its significance as landmarks for its rareness. Yeongdo Bridge, the sole bascule bridge in Korea was reconstructed in 2013 after being demolished because of its corrosion and aging, and now operates once in a day. Recently, safety inspections are executed thanks to demands getting higher for maintenance and safety of bridges, but measurement and analysis about bascule bridges are scarce. This study includes the analysis of the bascule bridge's behavior such as stress, vibration and reaction in normal condition and while it lifts up, based on measurement. We expect that this study will be used as an initial data to compare and confirm bridge's changes as service year and the number of operation increase.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.1
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• pp.1-9
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• 2007

The performance of the small scale cyclone incinerate system (100kg/hr) to process the sewage sludge containing high moisture is evaluated. The incinerate system design is based on properties of the domestic sewage sludge. The combustion characteristics of the incinerate system is tested and analyzed with the various operation conditions of the moisture level, the sludge feed rate and the auxiliary fuel feed rate. The pressure loss of the whole system is appeared relatively small of 700mmAq under the normal operating condition and the temperature distribution of the incinerator internal combustion is maintained less than 1000C. Auxiliary fuel of 4.7 1/hr is required to incinerate 100kg sludge which include 87% moisture. Because the inside temperature of the incinerator is maintained less than $1000^{\circ}C$, it is predicted that the most NOx measured is produced not from the heat during the combustion process but from the oxidation of the N ingredient in the sludge. From the component analysis of ash, the organic matter is not entirely detected. Accordingly, it is estimated that the complete combustion has been accomplished in the incinerator.

• The Transactions of the Korea Information Processing Society
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• v.4 no.11
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• pp.2832-2839
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• 1997

In this paper, a testing architecture and procedure that an idle ATM virtual channel can be utilized for TCP channel is proposed. Four kinds or methodologies for protocol conformance testing have been standardized in ISO. Remote testing method used popularly have some disadvantages that developer must operate system manually in case of System Under Test (SUT) active testing and we cannot control and observe Implementation Under Test (IUT) often. It is proper to adopt distribute testing method than remote test in order to maximize test coverage and optimize fault coverage for conformance testing in ATM systems, and it is required that TCP channel is prepared for distribute testing method. The proposed architecture can adopt distributed testing method without extra physical channel for testing control. Also we can maximize the test coverage and implement the automation of testing without intervention of operator sustaining normal operation of ATM equipment.

• Journal of the Korean Institute of Gas
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• v.11 no.2 s.35
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• pp.55-59
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• 2007

This paper presents the strength safety of a LPG cylinder, which is fabricated by a steel sheet forming and a welding technology. The strength safety of a cylinder is guaranteed by analyzing a stress distribution of a LPG cylinder structure using a finite element method. The FEM computed results indicate that the hydraulic test gas pressure of $31kg/cm^2$ generates a concentrated local stress near the upper round end plate, which exceeds the yield strength of a LPG cylinder. Thus, the current hydraulic test pressure may be rechecked and revised because this pressure increases the fatigue failure and decreases the lift of the pressure vessel. The normal operation and sealing gas pressures such as $9kg/cm^2\;and\;18.6kg/cm^2$ are relatively safe for a steel LPG cylinder.

• Journal of the Korean Institute of Gas
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• v.12 no.2
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• pp.85-91
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• 2008

The deviation of measured pressures in pipeline networks from normal or reference pressures is useful information for judging the operation of the pipeline networks. A cost-effective monitoring of pipeline networks including a leak detection capability can be realized when transient pressure variation is accurately predicted using measured conditions at supply- and demand-sides of the networks. In this study, a pipeline network analysis program was developed based on one-dimensional flow equations for compressible fluids. The validity of the present analysis was demonstrated by simulating the flow in a straight pipeline and comparing the results with the previously reported ones. Pressure and flow rate transients in several simple city-gas pipeline networks were also analyzed to show the usefulness of the developed program.

• Journal of Korean Society of Rural Planning
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• v.26 no.3
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• pp.91-102
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• 2020

The purpose of study was analyze the pumping characteristics, Irrigation Efficiency(IE), and irrigation pattern by period of rice growing stage with based on the performance of design irrigation water requirement and operational Galshin Pumping(GP) station in GP irrigation district constructed under rural water development project master plan. GP station was located in Yedang reservoir, Yesan-gun, Chungcheongnam-do and has been supplying irrigation water since 2006. The research data are the Irrigation Water Requirement(IWR) and the Pumping Water Amount(PWA) from 2006 to 2015 at the GP station, which is the supplied amount. The IWR were calculated using the Blaney-Criddle formula of the HOMWRS program, Hydrological Operation Model for Water Resource System, developed by Korea Rural Community Corporation. The Blaney-Criddle formula was used to calculate design irrigation water requirement of Galshin rural water development project master plan. During 2006-2015, the study period, the annual average IWR is 763.2(±149.1)mm, the annual PWA of the GP station is 397.4mm to 1,056.9mm, and those average annual PWA is 643.4(±208.4)mm. The annual IE of GP station 96.5% to 169.0%, and the average annual IE is 124.3%, which is higher than the research results conducted in other pumping stations. Analyzing the irrigation patterns of the GP irrigation district, the IWR Ratio per 10days(IWRR) and the PWA Ratio per 10days(PWAR) of the G P station were obtained. The IWRR is the percentage of IWR for each 10 days of a month to total IWR per year, and the PWAR is the percentage of PWA for each 10 days of a month to total PWA per year. The Kolmogorov- Smirnov(K-S) test results of IWRR and PWAR showed the characteristics classification by rice growing stage and stable normal distribution characteristics. Average IWRR(AIWRR) and Average PWAR(APWAR) are presented as irrigation patterns. Irrigation pattern analysis will be able to standardize comparison, analysis and probability calculation of the pumping station characteristics of different pumping stations and apply to objective evaluation of the pumping station district.

• Nuclear Engineering and Technology
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• v.50 no.2
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• pp.253-258
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• 2018

A microcell $UO_2$ pellet, as an accident-tolerant fuel pellet, is being developed to enhance the accident tolerance of nuclear fuels under accident conditions as well as the fuel performance under normal operation conditions. Improved capture-ability for highly radioactive and corrosive fission product (Cs and I) is the distinct feature of a ceramic microcell $UO_2$ pellet, and the enhanced pellet thermal conductivity is that of a metallic microcell $UO_2$ pellet. The fuel temperature can be effectively decreased by enhanced thermal conductivity. In this study, the material concepts of metallic and ceramic microcell $UO_2$ pellets were designed, and the fabrication process of microcell $UO_2$ pellets embodying the designed concept was developed. We successfully implemented the microcell $UO_2$ pellets and produced microcell $UO_2$ pellets. In addition, an assessment of the out-of-pile properties of a microcell $UO_2$ pellet was performed, and the in-reactor performance and behavior of the developed microcell pellets were evaluated through a Halden irradiation test. According to the expectations, the excellent performance of the microcell $UO_2$ pellets was confirmed by the online measurement data of the Halden irradiation test.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.398-400
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• 2011

Purpose: Subungual tumors are a common cause of nail plate deformity, and may be caused by fibrokeratoma, Koene's tumor and glomus tumors. Neurofibromas, either as part of neurofibromatosis or as a solitary tumor are exceptionally rare in the digits. Methods: A 44-year-old man presented with painless onychodystrophy and nail plate elevation of the right thumb due to a small subungual mass that had started growing 3 years ago. Sensory evaluation of the distal phalanx was normal, and no discoloration nor infection signs were seen. The nail plate was extracted under local anesthesia, and the mass was delicately removed without injury to the nail bed. The nail matrix was repaired with primary closure. Results: Histopathology shows a well circumscribed, cellular tumor with myxoid stroma. Tumor cells were S-100 protein positive, and the patient was diagnosed with myxoid neurofibroma. There has been no sign of recurrence to date, 14 months after the operation. Conclusion: Presentation of cutaneous neurofibromas in the digits is an uncommon finding. They may occur as a manifestation of neurofibromatosis or as a solitary tumor. Subungual neurofibromas are exceptionally rare. To our knowledge, there are only ten reports of solitary subungual neurofibroma unrelated to neurofibromatosis to date. We report a rare case of solitary subungual myxoid neurofibroma of the thumb, that was treated through total excision, with preservation of the nail matrix.

• Journal of Chest Surgery
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• v.39 no.3 s.260
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• pp.230-235
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• 2006

Systemic arterialization of lung with/without sequestration (Sequestration/Anomalous Origin of Left Pulmonary Artery, AOLPA) is a rare form of congenital anomalous systemic arterial supply to the lungs. In this anomaly, the arterial supply of one or more arteries of the basal segments of the lower lobe derives from an aberrant vessel arising from the aorta. We report two adult cases of systemic arterialization of normal basal segments of left lower lobe lung with/without sequestration. The one (AOLPA) was treated by left lower basal segmentectomy and the other (Sequestration) by therapeutic angiographic embolization. Based on the favorable follow-up result in our patients, although lobectomy (segmentectomy) is the basic treatment modality, embolotherapy could also be a mode of treatment that could be selectively applied to elderly, infirm patients or high risk patients with poor pulmonary function.