• Journal of Korean Society of Environmental Engineers
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• v.30 no.2
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• pp.234-238
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• 2008

Coarse pore filter could be an alternative of membrane for solid-liquid separation in an activated sludge reactor because of inexpensive cost of the filter material and high flux at low filtration pressure. However such filter module has much less specific filtration area compared to the membrane. Therefore a certain effort is required to increase the specific filtration area in the module design of such coarse pore filter for solid-liquid separation in an activated sludge reactor. In this study, tubular type coarse pore filter was designed at various diameter and configuration. The filtration performance was investigated to separate solid in the activated sludge reactor for domestic wastewater treatment. Tubular type coarse pore filter module could be successfully applicable to solid separation in the activated sludge reactor. The design parameters were the tube diameter of 10mm and vertical installation. Smaller diameter of the tube caused faster increase of the filtration pressure because of the hydraulic head loss in the tube channel.

• The KIPS Transactions:PartA
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• v.11A no.1
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• pp.75-80
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• 2004

To interact database data with GRID system, implementation and installation of data manipulation module which manipulates database data and its index is required. Developing a search system searching data on web-based database, and integrating it with grid system, it is possible that searching data on web and use it directly on GRID system without independent data module. So, we can build easy and effective grid system, and the system could have more flexible architecture adapting data change. In this paper, we propose a searching system which interacting web-based database with GRID systems. We integrated the searching system with a bio god system which runs virtual screening jobs. As a result, UB Grid (Universal Bio Grid) is constructed. Developer could reduce time and effort required to integrate web data to GRID system, and user could use UB Grid system easily and effectively.

• The Journal of the Korea Contents Association
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• v.14 no.5
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• pp.411-424
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• 2014

This study tries to establish the evaluation standards of the service quality of local cultural festivals in an effort to identify public awareness of those festivals. Also, based on the importance-performance importance-performance analysis on the service quality, this research is aimed at finding ways to enhance service quality and to improve operation plans in more efficient ways for the maximization of visitors' use of festivals. Ultimately, the current study seeks to make a contribution to improving the quality of local cultural festivals. The results of the correspondence t-test analysis of importance and performance revealed that significant differences were found in following items of five factors; 1) in the responsiveness factor, the presence or absence of rest space, facility guide, communication, and installation of public restroom/cleanliness 2) in the certainty factor, food prices and staff members' kindness 3) in the reliability factor, all items including festival pamphlets (to the festival venue), guidance facilities/signposts, hospitality, schedule information, and quick responses 4) in the tangibility factor as well, all items such as the awareness of local culture, benefits, and storytelling 5) in the empathy factor, diversity of events and festival contents.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.2
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• pp.41-55
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• 2005

In an effort to preserve biodiversity in increasingly fragmented green patches, Korea has been installing eco-corridors over or under some arterial or expressways. In a survey of 43 such eco-corridors installed up until the year 2003, some problems and issues were identified. Some selected overseas eco-corridors were also investigated to find implications for the improvements of future installations in Korea. Major findings are; - For most existing eco-corridors, target species are not specified and locations of the eco-corridors are not well considered, and consequently it is questionable if wildlifes are crossing them - Most of existing eco-corridors lack supporting facilities such as fences that guide wildlife to cross them and prevent them from running into the road - Planting on the eco-corridors is not sufficient, not diverse enough in species, and not very considerate of wildlife but designed and planted in a similar manner as in urban parks - Where target species are not well specified, the location, width, cross section, and other aspects of the eco-corridors can not be optimized - It is suggested that eco-corridors are planned at early stages of road planning so that the number and locations of eco-corridor(s) decided as necessary and even the alignment and design of roads consider the installation of eco-corridors in advance - Monitoring of wildlife crossings is needed for improved eco-corridor planning and design - Nationwide green network plan is desirable to be made first and eco-corridors fit into it.

• Journal of Welding and Joining
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• v.33 no.3
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• pp.62-67
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• 2015

A very large shell-structure built in shipyards like ship hulls or offshore structures are joined by welding through full process. As the welding contains a high thermal cycle at a local area, the welded structures should be distorted unavoidably. Because a distorted ship block should be revised to the designed value before the next stage, the ability to predict and to control the weld distortion is an accuracy level of the yard itself. Despite the ship block size, several present thermal distortion methodologies can deal those sizes, but it is a different story to deal full ship size model. Even a fully constructed ship hull not remaining any welding can have an accuracy issue like outfitting installation problems. Any present thermal distortion methodology cannot accept this size for its recommended element size and the number. The ordinary welding breadth at erection stage is about 20~40 mm. It can hardly be a good choice to make finite element model of these sizes considering human effort and computational environment. The finite element model for structure analysis of a ship hull is prepared at front-end engineering design stage which is the first process of the project. The element size of the model is as fine as the longitudinal space, and it is not proper to obtain a weld distortion at the erection stage. In this study, a methodology is suggested that a weldment can be shrunk at original place instead of using structural finite element model. We cut the original shell elements at erection weld-line and put truss elements between the edges of cut elements for weld shrinkage. Additional truss elements are used to facsimile transverse weld shrinkage which cannot be from the weld-line truss element shrink. They attach to weld-line truss element like twigs from barks. The capacity of developed elements is verified through an accuracy check of erection process of a container vessel at the apt. hull. It can be a useful tool for verifying a centering accuracy after renew and for block-separating planning considering accuracy.

• Journal of Forest and Environmental Science
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• v.34 no.2
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• pp.176-179
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• 2018

To restore the connectivity of fragmented habitats, 415 wildlife crossings have been built between 1998 and 2014 in South Korea. However, their effect on wildlife conservation is still in doubt. As a first step to examine the effectiveness, our study aims to assess compliance with the guideline for wildlife crossing construction and management, developed by the Ministry of Environment Korea that provides fundamental information to understand the status and the problem of wildlife crossings in Korea and thus to provide practical guidance for the improvement. According to our survey, the Korea National Park Service complied with the guideline best (62.5%) while local government followed the guideline least (46.1%). In addition, the compliance rate was the highest for wildlife crossings in national roads (53.6%) followed by highways (53.2%) and local and municipal roads (52.2%). For the overpass wildlife crossings, the compliance rates for installation of an escaping facility in the drainage and prevention of pedestrian and vehicle access were particularly low. In case of underpass wildlife crossings, small ditches for amphibians and reptiles were not sufficient, and the linkage between wildlife fences and underpass were weak. In order to ensure the effectiveness of wildlife crossings, the effort to increase the compliance rate with the guideline is critical, and mandating the guideline could be a practical way to enforce the compliance.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.248-259
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• 2010

In the case of relatively good ground and construction condition in the deep excavation for the construction of subway, railway, building etc., flexible earth retaining systems are often used in an economical point of view. It is generally known that the mechanism of behavior in the flexible earth retaining system is relatively more complicated than the rigid earth retaining system. Moreover in the case of long span strut supporting system the analysis of strut axial force change becomes more difficult when the differences of ground condition and excavation work progress on both sides of excavation section are added. When deeper excavation than the specification or installation delay of supporting system is done or change of ground condition is faced due to the construction conditions during construction process, lots of axial force can be induced in some struts and that can threaten the safety of construction. This paper introduces one example of long span deep excavation where struts and rock bolts were used as a supporting system with flexible wall structure. The characteristics of ground deformation and strut axial force change, the measured data obtained during construction process, were analysed, the effects of relatively deeper excavation than the specification on one excavation side and rapid drawdown of ground water level on the other excavation side were deeply investigated from the viewpoint of mutual influences between ground deformations of both excavation sides and strut axial force changes. The effort of this article aims to improve and develop the technique of design and construction in the coming projects having similar ground condition and supporting method.

• KIEAE Journal
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• v.8 no.4
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• pp.63-69
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• 2008

The thesis is a comparative analysis of Infill Technologies between Korea's long-life Mock-up House, a study driven by 'Durability and Flexibility of Long-life Housing Technology Development' of R&D, and Japan's KSI experimental house, the major example of Japan's long-llfe housing. In terms of the domestic Mock-up House, a system of building the floor first was applied. The floor material of each housing unit required a development of dry heating component that is partially substitutable in order to avoid conflict with the finishing. Also, a development of a floor system that can counteract against the construction inaccuracy was required. In the Case of an outer wall, need to make the wall with the chassis. In the case of ceiling, need to develop the double ceiling system which is good for sound insulation. Also, in comparison to KSI experimental house in Japan, it would require to develop a wiring system of the ceiling which can react to the movement of the wall. Especially, to assure the flexible nature of an internal wall, it would desperately require the research and development of the products related to components and flexible system of mechanical/electrical/communication parts as well as supporting institutionalized system for this development. Furthermore, for KSI experimental house in Japan, it would be necessary to formulate a construction manual as well as a systematic and practical planning guide to invent a new interface rule which will secure simplicity of assembling, dismantling, installation and replacement of architectural components for which research development is quite insignificant at the moment. This effort will have to continue to give a solid direction for better application of such reference manual during construction and development of long life span apartment by public sector as well as private corporations.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.354-359
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• 2012

With the long-term use of fossil fuel, the whole world is suffering from serious abnormal changes in weather caused by global warming. For this reason, many countries are reducing greenhouse gas emissions out of obligation and the allowable emissions are assigned to each country. Korea is also putting much effort into reducing greenhouse gas emissions by 30 percent against BAU(Business As Usual) by 2020, and is pushing ahead with several projects such as 'Million Green Home' and 'Hatsal Gaduk Home' to expand the use of new renewable energy in house as part of its policy. This study was designed to come up with improvements and help to expand photovoltaic facilities, by investigating and analyzing the current state of photovoltaic facilities in the country and problems in installing them through an in-site reconnaissance and a survey in Jecheon area. As the result, it was found that residents in the area were inadequate to operate and install photovoltaic facilities, lacked awareness of them and felt burdened economically by managing and installing them, although they had a high awareness of solar energy and photovoltaic facilities are constantly increasing with governmental support. In conclusion, it is considered that as improvements, operational effects should be increased through development of techniques, factors to reduce the effects in operating them due to insufficient management and installation should be removed and awareness of residents need to be improved through long-term plans, political support and education of the government.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.3
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• pp.42-48
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• 2016

Extensive research effort has been made during the last decade to utilize wireless smart sensors for evaluating and monitoring structural integrity of civil engineering structures. The wireless smart sensor commonly has sensing and embedded computation capabilities as well as wireless communication that provide strong potential to overcome shortcomings of traditional wired sensor systems such as high equipment and installation cost. However, sensor malfunctioning particularly in case of long-term monitoring and unreliable wireless communication in harsh environment are the critical issues that should be properly tackled for a wider adoption of wireless smart sensors in practice. This study presents a wireless smart sensor network(WSSN) that can estimate unmeasured responses for the purpose of data recovery at unresponsive sensor nodes. A software program that runs on WSSN is developed to estimate the unmeasured responses from the measured using the Kalman filter. The performance of the developed network software is experimentally verified by estimating unmeasured acceleration responses using a simply-supported beam.