• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.256-259
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• 2008

Ejector system is a device to transport a low-pressure secondary flow by using a high-pressure primary flow. Ejector system is, in general, composed of a primary nozzle, a mixing section, a casing part for suction of secondary flow and a diffuser. It can induce the secondary flow or affect the secondary chamber pressure by both shear stress and pressure drop which are generated in the primary jet boundary. Ejector system is simple in construction and has no moving parts, so it can not only compress and transport a massive capacity of fluid without trouble, but also has little need for maintenance. Ejectors are widely used in a range of applications such as a turbine-based combined-cycle propulsion system and a high altitude test facility for rocket engine, pressure recovery system, desalination plant and ejector ramjet etc. The primary interest of this study is to set up an applicable model and operating conditions for an ejector in the condition of sonic and subsonic, which can be extended to the hydrogen fuel cell vehicle. Experimental and theoretical investigation on the sonic and subsonic ejectors with a converging-diverging diffuser was carried out. Optimization technique and numerical simulation was adopted for an optimal geometry design and satisfying the required performance at design point of ejector for hydrogen recirculation. Also, some ejectors with a various of nozzle throat and mixing chamber diameter were manufactured precisely and tested for the comparison with the calculation results.

• Journal of Korean Tunnelling and Underground Space Association
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• v.5 no.1
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• pp.55-70
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• 2003

Ammunition magazine, which is installed on the ground, has difficulty in protecting from the external attack, and accidental explosion should cause great damage to the life and property. For these reasons, it is needed to develop underground magazine that it has the advantages of safety, security and maintenance. This paper introduce the design case for blasting facilities, which should resist blasting pressure, as well as layout of underground magazine, which takes a safety for explosion and a working space of loading/unloading machine into consideration. On the layout, in case of ${\bigcirc}{\bigcirc}$ underground magazine, put three storage chambers in position almost parallel with principle stress direction, where less effected on discontinuity and hard rock area. Also, secured safe distance according to safety criteria of the Defense Ministry, and verified suitable layout by trace simulation for loading/unloading machine on working stage. Blasting design was performed on evaluation of maximum blast pressure between donar and acceptor chambers, and design condition for blast door, valve, etc. Diminution facilities against explosion, such as thrust block or debris trap, determined its size after plan in accordance with blasting criteria and calculation by structural analysis.

• The Journal of the Korea Contents Association
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• v.16 no.3
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• pp.257-268
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• 2016

The purpose of this research is to find the cause of low degree of utilization of medical equipment that are provided as Official Development Assistance(ODA) and to suggest an effective medical equipment support system for ODA. This research analyzes the supporting process of the medical equipment as ODA in Kitengela Health Center in Kenya. As the result of analysis, it has been found that the following problems. 1) It was found that users was attended insufficient to demand medical equipment. 2) The determination of medical equipment request was inadequate. 3) It was appeared to be organized the compilation of the budget for purchases and operation of medical equipment 4) The improvement of procurement system of medical equipment was appeared to need. 5) It was appeared to need to build conditions for installation of medical equipment. 6) It was necessary to secure finance, to conduct periodic management training, and to ensure available human resources in management and maintenance in order to sustain the medical equipment management ability and it is encouraged to promote leadership in healthcare facility management. Finally, the theoretical and practical implications of this research are discussed.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.433-440
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• 2013

The Ministry of Land, Infrastructure and Transport was developed the Construction CALS system for improvement of the construction economy. Construction CALS system is consist by Construction Portal System, Construction Management System, Construction Authorization and Permission System, Compensation Management System, Facility Maintenance Management System and has utilized at construction site of more than 900. Ministry of Land, Infrastructure and Transport and related researcher was proposed method of various function improvements for usability of the system. However, the proposed method was expanded the problems like increase of system management cost and development cost with decrease of data process rate. The problem was increases because has added of only service function without modify of software structure to the system on each different platform base. One of the methods for solving problems is to apply the e-Government framework and then integrated the different platform. The purpose of this paper is analyse of the applicability and efficiency of e-Government framework to the construction CALS system. For that was analyzed the e-Government standard framework and the developments case. And then was verified about the adaption possibility and efficiency by use the Function Point tool.

• Journal of Advanced Navigation Technology
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• v.19 no.4
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• pp.305-310
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• 2015

A controlling system for airport refueling facilities is connected to sensors which collect various informations. Informations which are transmitted at a high speed in various sensors are processed by a dedicated software in the controlling system. The problems of system maintenance and network traffic caused by the use of dedicated software reduce the efficiency of the system operation. Therefore, a web-based system that can be accessed using the Internet environment is required. In this paper, we propose a system showing web-based real-time informations. To do this, we change the function of the communication by each sensor to a facade structure, and design a system for transferring web-based real-time informations. Also we propose data-driven infographics for displaying the real-time big data information at a high speed on the web. Finally, we compare and analyse the proposed system between the existing system and show that our system can effectively display the real-time information on the web.

• Land and Housing Review
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• v.10 no.4
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• pp.1-12
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• 2019

The purpose of this study is to set the direction of development of the design guideline of the New-Hanok-Style public building in apartment complex and to use it as basic data for future architecture plans. The existing Hanok architecture standards and guidelines were analyzed and the characteristics of New-Hanok-Style Public Building in apartment complex were applied. The planning direction of the design guideline was derived. First, although the criteria and guidelines related to the Hanok produced and distributed were classified differently according to the purpose of production, the details and contents were similar. Second, the general planning criteria items were divided into layout, external space plan, building plan, and performance plan. Third, the elements of 'creative inheritance of traditional architecture' and 'modern building technology', which are the characteristics of New-Hanok-Style Public Building, were applied. In addition, we analyzed elementary welfare facility guidelines and applied elements such as layout type and zoning setting. Fourth, a special planning standard for applying the building system required for the New-Hanok-Style Public Building in apartment complex was added. In the future, it is expected to revitalize New-Hanok-Style Public Building containing the unique identity(genetic factor; DNA) of the nation by developing and disseminating relevant building standards, design guidelines, and maintenance manuals.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.06a
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• pp.95-112
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• 1998

Water quality in the public water course has been polluted more seriously than ever before due to the increase of the number and aremount of pollution sources such as domestic and industrial wastewater. For water quality conservation, the Korean government has been trying to construct sewage treatment facilities continually, of which treatment capacity reached to 11,452,400m$^{3}$/day in 1996. Night soil treatment facilites of m nationwide have the treatment capacity of 24,038m$^{3}$/day. But water quality has not been improved because the sewer systems were insufficient and the treatment efficiencies of sewage were not high, enough. For renovation of water quality, miscellaneous domestic wastewater must be treated because 27g BOD/day out of total 40g BOD/person-day come from miscellaneous wastewater, comparing to 13g BOD/day from night soil. However, sole treatment purifier treat only night soil from the flushing toilet. Therefore, it may be desirable to treat the miscellaneous domestic wastewater and the night soil from flushing toilet together by joint treatment purifier system as on-site domestic wastewater treatment technology. In Korea, the joint treatment purifier system, introduced in 1997, have the benefit as follows; i) good water poiluion control effect, ii ) good effect on river water flow, iii) water pollution control with sewage treatment facility, and iv) rapid pollution control effect, etc. In order to achieve a good effect as stated before, i ) strengthening effluent guideline including BOD, nitrogen and phosphorus, ii ) specializing operation to maintain high performance, and iii) supporting its construction and maintenance costs by the governmental level may be necessary: In addition, automation system of joint treatment purifier, technology for its package and compactness, and a new bio-media bio-filter with higher capacity should be further developed in agreement with a more stringent effluent guideline.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.348-354
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• 2018

This study proposes MF (Model Filter)-based M-BDL (MF-based BIM Data Linkage), which is a model filter-based data mapping method for BIM (Building Information Modeling)-BEMS linkage. Recently, BEMS (Building Energy Management System) is actively utilizing 3D spatial information. This allows the user to intuitively manage the facility energy linked to spatial information. To use BIM data in energy management systems, it is essential to link BEMS with BIM data only in terms of the user requirements. On the other hand, if the BIM is a rich dataset and is linked as it is, the user will need to manage the unnecessary information. By mapping only the data required for BEMS in heavy BIM data through M-BDL, the BIM data can be lightened and the amount of data required for maintenance can be reduced. This technology proposes a mapping method that can link the BIM data with the filtered BIM data.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.4
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• pp.231-236
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• 2011

When the Fukushima nuclear power plant accident occurred in March of 2011, a hydrogen explosion in the reactor building at the 4th unit of Fukushima plants led to a big surprise because the full core of the unit 4 reactor had been moved and stored underwater at the spent nuclear fuel storage pool for periodic maintenance. It was because the possible criticality in the fuel storage pool by coolant loss may yield more severe situation than the similar accident happened inside the reactor vessel. Fortunately, it was assured to be evitable to an anxious situation by a look of water filled in the storage pool later. In the paper, the safety state of the spent fuel storage pool and rack structures of the domestic nuclear plants would be roughly reviewed and compared with the Fukushima plant case by engineering viewpoint of potential severe accidents.

• Journal of Conservation Science
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• v.29 no.4
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• pp.407-420
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• 2013

The stone sculptures in Gyeongbokgung Royal Palace are mainly composed of granite (884 sculptures, 96.7%) and marble (25 sculptures, 2.7%) that originated in several different quarries. Main deterioration forms are crack (24%), break-out (21%), exfoliation (36%), granular disintegration (9%) and blackening (20%). Crack and break-out are dominant contributors to high physical deterioration degree, and blackening is major weathering form of intensive discoloration. The Gyeonghoeru, Geunjeongjeon and Pumgyeseok areas require urgent and high conservation maintenance with short-term periodic monitoring since proportions of 3-grade deterioration were calculated higher than others as 55% for Gyeonghoeru, 29% for Geunjeongjeon, 11% for Pumgyeseok area. The Pumgyeseok (officials' rank stone), especially, needs intervention for protective facility due to its material vulnerability to weathering in outdoor environment.