• Journal of Korean Society of Water and Wastewater
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• v.27 no.6
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• pp.711-721
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• 2013

Optimal operation of a combined sewer network with distributed storage facilities aims to use the whole retention capacity of all reservoirs efficiently before overflows take place somewhere in the considered network system. An efficient real-time network control (RTNC) strategy has been emerging as an attractive approach for reducing substantially the overflows from a sewer network compared to the conventional fixed or manually adjusted gate setting method, but the related concrete framework for RTC development has not been throughly introduced so far. The main goal of this study is to give a detailed description of the RTNC systems via reviewing several guidelines published abroad, and finally to suggest methods for the proper application of RTNC on distributed storage facilities. Especially, this study is focused on emphasizing the importance of hierarchical structure of RTNC system that consists of three control layers (management, global control and local control). Further, with regard to the global control layer which is responsible for the central overall network control, the wide-ranging details of two components (adaption and optimization layers) are also presented. This study can provide the valuable basis for the RTNC implementation in the particular sewer network with distributed multiple storage facilities.

• Journal of the Korean association of regional geographers
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• v.14 no.3
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• pp.199-211
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• 2008

This study looks into existing discussion about the entry time and the geographical criteria point of 'Ho-Nam' as a place name. And discusses the reason which the geographical criteria point is not clear with emphasis on the possibility of the geographical range change of place name. The result is as follows. Firstly, the regional criteria of 'Ho-Nam' is Kum-River if we consider direction and the role as a regional barrier among the existing offered criteria. Secondary, the criteria of Ho-Nam and Ho-Seo might be different each other. A place name of Ho-Nam had appeared before Chosun period as a geographical concept and changed to the cultural concept during Chosun period. And Ho-Seo was established in Chosun period. But 'Ho-Nam=Jeon-la Province' and 'Ho-Seo=Chung-cheong Province' is established during Chosun period as a cultural concept. Thirdly, the geographical range of Ho-Nam of Go-Ryeo period and Chosun period were different each other. Fourthly, the criteria of Ho-Nam may be the Han-River if we consider the entry time and geographical range change.

• Journal of the Korea Concrete Institute
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• v.25 no.3
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• pp.295-304
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• 2013

Ultra-High Performance Concrete (UHPC) has recently been one of the most active research fields in Korea as well as in foreign countries, because it can contribute to a longer life and economic efficiency of structures. Although precast-type UHPC fabricated in a factory is preferable in terms of quality control and reduction of construction period, there exist, even in the precast structure, some parts that need to be cast in-place such as the joints between precast segments. In the cast-in-place UHPC, however, it is probable that an optimum curing condition can hardly be realized in contrast to the factory production. In this study, therefore, the trend of compressive strength development of UHPC was experimentally investigated by assuming various inferior curing conditions that may be anticipated at a construction site. Concrete specimens were fabricated and cured under different conditions with the variables such as curing temperature, delay time before the initiation of curing, duration of curing time and moisture condition. The strengths were compared with those of the specimens cured by standard high temperature steam. Through the analysis of the test results, some minimum requirements for curing have been proposed that are required when the UHPC is cast in-place. It is expected, through this study, that practical use of UHPC in construction sites can be increased.

• The Korean Journal of Ceramics
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• v.2 no.4
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• pp.251-256
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• 1996

Effect of mixed grinding with a planetary ball mill of starting materials before heat treatment on the crystal structure and superconduction properties in the YBaCu composite oxide was studied. The size reduction of powders too place in the early stage of grinding, followed by aggregation of the resultant fine particles. The uniformity of the composition in the mixture was improved with grinding, which later decreased in the crystal grain size and well distribution of twin phase in the sintered bodies. The critical current density of the sintered bodies obtained from the mixture ground for 60 minutes showed the maximum value about 150 A/$\textrm{cm}^2$, while critical temperatures were around 90K and were independent of the grinding time.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.2
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• pp.106-111
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• 2007

In this research work attempts were made to study the bonding of thermo-plastics with adhesives using solar radiation. In order to study the curing behaviour necessary experiments were conducted under varying conditions of temperature, exposure time and power of solar energy. The cured samples were then studied under the optical microscope before subjecting to tensile testing in order to study their mechanical properties of thermo-plastics. The fracture surfaces were further studied under the Scanning Electron Microscopy(SEM) in order to research the microstructural changes that are taken place during curing. In order to measure the performance of solar energy cured joints the parameters such as; bond strength, surface morphology, the microstructual changes, variation in properties of adhesives bonded joints are compared to that of specimen cured at ambient conditions and specimen cured using microwave techniques.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.974-979
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• 2007

From '1994 Gwacheon accident of the Electric Multiple Unit(EMU)' till '2004 Seoul subway 2 lines Guui station accident', the accident is increasing at day and the service demand of the citizen is coming to be various. But it does not deal with technical or operation side demands. There is a possibility of saying that the accident of the EMU or deficit operation is caused by the RCM. The EMU where the efficiency is good though does the time passes and it becomes old anger and does not display that efficiency not only the cause of formation accident does becomes. The breakdown about under occurring before getting up an accident, appropriately shifting the parts is to a maintenance very the pending question fact which is important is a possibility of doing. From there is by an EMU, RCM in reliability base grudge is a tool of confirms an improvement point and the place where it judges. From the research which it sees will present about technical development plan of RCM.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.532-533
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• 2006

In this research work attempts were made to study the bonding of thermoplastics with adhesives using solar energy. In order to study the curing behaviour necessary experiments were conducted under varying conditions of temperature, exposure time and power. The cured samples were then studied under the optical microscope before subjecting to tensile testing in order to study their mechanical properties. The fracture surfaces were further studied under the Scanning Electron Microscopy in order to study the microstructural changes that are taken place during curing. From the present study it is evident that curing under higher solar energy temperature, generally improves bond strength and quality of the adhesive joints when compared to other modes of curing process expect the microwave curing process.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.754-759
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• 2008

Recently, the construction of buildings and large bridges has been increasing rapidly causing foundation structure growing larger then before, especially in the use of large size cast-in-place piles. Barrette Pile will usually be used at the site where diaphragm wall is the retaining wall to save time and cost in mobilization of equipments. This study uses bi-directional loading test data obtained from two different sites to observe the bearing capacity and displacement characteristics of barrette pile. Numerical analysis of the test is done by using commercial 3D computer program and the interface effect and capacity of the pile as well as displacement characteristics of the pile is verified.

• Restorative Dentistry and Endodontics
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• v.24 no.2
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• pp.426-429
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• 1999

When the tooth avulsion occur in accidents the drying damage to the periodontal ligament has extremely detrimental effects on healing. Pulp necrosis always occurs after an avulsion injury, but revascularization can only take place in teeth with immature apexes. Therefore complications after avulsion injuries are common, and treatment must be carried out in a timely and correct fashion to prevent or limit these complications. Every effort should be made to replant the tooth within the first 15 to 20 minutes. If doubt exists that the tooth can be replanted adequately, the tooth should quickly be stored in an appropriate medium until the patient can get to the dental office for replantation. A complication of inflammatory root resorption is occurred by bacterial infection of periodontal ligament and dental pulp. Therefore aseptic endodontic treatment must be carried out in a timely and systemic antibiotics given at the time of replantation and before endodontic treatment are effective in preventing bacterial invasion. Further studies are needed to establish the clinical importance of preparation of the socket and root.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1177-1178
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• 2007

There is a possibility of saying that the accident of urban transit vehice or deficit operation is caused by the m.aintenance. urban transit vehice where the efficiency is good though does the time passes and it becomes old anger and does not display that efficiency not only the cause of formation accident does becomes. The breakdown about under occurring before getting up an accident, appropriately shifting the parts is to a maintenance very the pending question fact which is important is a possibility of doing. From there is by an urban transit vehice, Mauntenance in reliability base grudge is a tool of confirms an improvement point and the place where it judges. From the research which it sees will present about technical development plan of Maintenance.