• Journal of the Korean GEO-environmental Society
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• v.9 no.2
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• pp.47-59
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• 2008

Application of mechanically stabilized earth wall (MSEW) abutment has been rapidly increasing in United States of America, Pennsylvania since 2002. MSEW is effective for reducing construction cost and period compared to general concrete reinforced wall. In the paper, theoretical background and conventional criterion of MSEW abutment that is widely used abroad are analyzed. Based on the results, application of suitable MSEW abutment to domestic bridge type is examined. For the application of MSEW abutment in Korea, load interacting with upper shoe in domestic bridge types and structural analyses of beam seat and pile are investigated. As a result, all applications are possible except for PSC BOX Bridge that has heavy self-weight of girder. Through two and three dimensional numerical analyses, horizontal behaviour mechanisms between pile and MSEW were analyzed and field tests are also carried out for seven piles behind earth walls. From results of field tests, it is confirmed that an angle of internal friction of backfill material needs to be greater than 34 degree to use H-Pile as foundation of MSEW.

• Smart Structures and Systems
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• v.21 no.3
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• pp.305-320
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• 2018

The second half of the 20th century was marked with a significant raise in amount of railway bridges in Austria made of reinforced concrete. Today, many of these bridges are slowly approaching the end of their envisaged service life. Current methodology of assessment and evaluation of structural condition is based on visual inspections, which, due to its subjectivity, can lead to delayed interventions, irreparable damages and additional costs. Thus, to support engineers in the process of structural evaluation and prediction of the remaining service life, the Austrian Federal Railways (${\ddot{O}}$ BB) commissioned the formation of a concept for an anticipatory life cycle management of engineering structures. The part concerning concrete bridges consisted of forming a bridge management system (BMS) in a form of a web-based analysis tool, known as the LeCIE_tool. Contrary to most BMSs, where prediction of a condition is based on Markovian models, in the LeCIE_tool, the time-dependent deterioration mechanisms of chloride- and carbonation-induced corrosion are used as the most common deterioration processes in transportation infrastructure. Hence, the main aim of this article is to describe the background of the introduced tool, with a discussion on exposure classes and crucial parameters of chloride ingress and carbonation models. Moreover, the article presents a verification of the generated analysis tool through service life prediction on a dozen of bridges of the Austrian railway network, as well as a case study with a more detailed description and implementation of the concept applied.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• no.1
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• pp.167-175
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• 2001

After World War II, Japan experienced a great political and social shift, which brought a concern of emerging public landscape in urban development. This paper analyses the management of the aesthetic intentions in urban design effort. We reviewed the development of various public installation of artworks concerning urban landscape aesthetics through its administrative process in chronological order. The monuments during the first decade marked a shift in emphasis from the militarism of the pre-war and wartime period to one of peace. However, some of the monuments and sculptures are not immune to controversy. This became an issue that could no be ignored by public officials whose responsibility was to place the sculptures while maintaining sensitivity to public opinion. As public administrators began to consider the possibility that sculptures may contribute to improving public amenities, the contextual concepts were basically ignored. Some of the programs in 1970s began to show more respect to the context, while other programs in this period expressed more interest in educational aspects of sculptures in the public spaces. Urban development projects also seek to introduce artworks integrated to their urban design concepts in 1990s. Generally, the administrators responsible for these programs were rarely trained in any relative field study other than public administration. Installing sculptures tended to be considered as part of public works projects on the level of urban planning and construction. The general public is basically removed from participating in the critical decisions that actually impact their lives in relation to the artworks. In conclusion, public art in japan has unique social and historic background both in its advantages and disadvantages. Issues pertaining to art in public spaces have evolved over the decades as the term "sculpture pollution" began to appear by the mid 1990s. most of the problems originated in either the lack of monumentality, contextual consideration, quality, or public participation. From another point of view, these programs played great roll in the development of modern Japanese sculpture and patronizing process, and the creation of new urban landscape with aesthetic value. In this sense, they must be considered as successful and noteworthy examples of cultural administration and urban design policy.

• Journal of the Korean Institute of Landscape Architecture
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• v.13 no.2
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• pp.13-26
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• 1985

^x The enviroment defines the living conditions for people and has at the same time the possibility to create new environment. In Korea, where the rate of urbanization reached more than 50% in 1970′s the priority has been put on the economic development and administrative function. Under the circumstance, visual environmental field was dealt lightly and it resulted in undesirable environment. The techniques of Mordern Arts (Montage, Depeysment, Tromp L′oeil, P.O.P Art, etc.) helped Super Graphics appear in the urban areas. Environmental Art has been expended into the public space and people came to recognize the Arts as the "Street Art" or "Street as Gallery". Super Graphics has four types 1) Resident′s Super Graphics ; Minority groups came to maintain social equality and rights, in cooperation with each other. Such maintenance required general urbanites to form communities which gave birth to the community art, Mural Painting. 2) Environmental Super Graphics ; Beauty has come to be stressed in order to improve the quality of urban lives in the course of inescapable urban development. Instead of renewal of all established construction conservation oriented renewal was encouraged. 3) Super Graphics as Population Arts ; In the 1960′s artists repulsed the establishments in an efforts to open new phase independent from the expressional in the arts. They recognized the relationship between painting, society and the public in different angle and tried to describe all living space on canvas. 4) Super Graphics as Advertisement ; Super Graphics functions as efficient media to deliver images to the urbanites. Super Graphics as media plays the role for political propaganda and commercial advertisements according to their purposes. In Korea, especially, it is required to introduce the environmental Super Graphics. But it is desirable to introduce Super Graphics with Korean culture and sense of beauty. Designers themselves are also required to have responsibility to improve the quality of urban culture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.6
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• pp.1428-1442
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• 2007

Nowadays, as IT environment is changing rapidly, traditional infra system such as hardware, software, and development methodology are changing as well. Legacy system has been filled with Intellectual property such as invested budget and development period for the time of IT is developing. Many countries around the world are having troubles with how to manage the legacy system. It is time to study on a development method and the implementation of supporting tool to reuse or process the legacy system. In this paper, it proves the definition, concept and also background of legacy system by showing real market and technology trend. Developed to handle the concrete development methodology, procedure and reference. We can get more profitability and productivity advance by reuse of legacy system and maintenance cost-saving through legacy migration.

• Environmental Engineering Research
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• v.17 no.4
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• pp.185-190
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• 2012

Rejection characteristics of perchlorate ($ClO_4^-$) were examined for commercially available reverse osmosis (RO) and nanofiltration (NF) membranes. A bench-scale dead-end stirred-cell filtration system was employed to determine the toxic ion rejection and the membrane flux. Model water solutions were used to prepare $ClO_4^-$ solutions (approximately, $1,000{\mu}g/L$) in the presence of background salts (NaCl, $Na_2SO_4$, and $CaCl_2$) at various pH values (3.5, 7, and 9.5) and solution ionic strengths (0.001, 0.01, and 0.01 M NaCl) in the presence of natural organic matter (NOM). Rejection by the membranes increased with increasing solution pH owing to increasingly negative membrane charge. In addition, the rejection of the target ion by the membranes increased with increasing solution ionic strength. The rejection of $ClO_4^-$ was consistently higher for the RO membrane than for the NF membrane and $ClO_4^-$ rejection followed the order $CaCl_2$ < NaCl < $Na_2SO_4$ at conditions of constant pH and ionic strength for both the RO and NF membranes. The possible influence of NOM on $ClO_4^-$ rejection by the membranes was also explored.

• Journal of Navigation and Port Research
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• v.37 no.6
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• pp.587-595
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• 2013

Establishment and operation of Aids to Navigation in the process of port design, construction and management are crucial factor of maritime safety and collision prevention. According to the IMO SOLAS Chapter 5, regulation 13, the establishment and operation of maritime safety facilities are mandated for the competent authorities. The facilities of Aids to Navigations are moving to a concept of e-Navigation with state-of-the-art technology of radio navigation equipments such as AIS, DGPS and e-Loran from the traditional visual facilities (optics, shape), Although the autonomous maritime traffic system is a new trend, yet the traditional and conventional Aids to Navigation like lighthouses and beacons are still imperative for vessel's safe navigation. In this paper, for decision of service level of maritime traffic facilities to enhance the efficiency of visual navigation system management it was proposed the Aids to Navigation availability as an efficient management system incorporating the whole maritime traffic facilities under one management system. Comparison of foreign level of services and analysis of the theoretical background of them were analyzed and the proposed LOS was applied to Incheon area to evaluate the safety of navigation routes.

• The KIPS Transactions:PartA
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• v.14A no.3 s.107
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• pp.159-166
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• 2007

A arrival of u-teaming paradigm requires many u-teaming system and model that is varied and support to distance education, Accordingly, the distance education system in u-learning environment has attracted a fair amount of critical attention. However there remain many questions, as yet unresolved, such as it is difficult to maintain interaction between tutor and learner, the construction of system is a great expense to them, a tutor, who manages the system, lacks technologic background, in most current distance education system. To solve these problem, some preliminary observations have to be made first: to keep teaming process in situation that it is unconnected with tutor, to construct the system economically, and to make to be easy-to-use. Therefore, in this paper, we develop the 'Intelligent U-Learning System using Cyber Tutor', which includes the conception of u-learning such as mobility, immanency, supports to keep learning without real tutor by cyber tutor, and removes technological and economical costs, verify the validity.

• Journal of Korean Classical Literature and Education
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• no.35
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• pp.47-85
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• 2017

In literary works, space plays a background role, but in geography, it becomes the target of study. Space could, therefore, be a matter of common interest in literary and geographic education. "Chunhyangjeon" contains a great amount of geographic information, such as landscape, itineraries, and spatial consciousness. This information is a part of narrative development and represents the geographical situation of the late Yi-dynasty. Thus, "Chunhyangjeon" could be the common material for literary and geographic education. Using "Chunhyangjeon" as the common material, through narrative incidents, learners in a literature class can appreciate the role of geographic information in narrative development, and the same learners can, in geography class, recognize the geographic information and gather the sense of place that the characters experience. For the construction of common realm of the two subjects, it is necessary to compare the aims of two subjects and systematically ensure that the aims correspond. This systematic correspondence of aims could be the foundation for curriculum integration.

• Computers and Concrete
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• v.24 no.5
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• pp.459-468
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• 2019

The stability and safety of concrete plug structure of diversion tunnel is crucial for the impoundment of upstream reservoir in hydropower projects. The ongoing Wudongde hydropower plant in China plans to adopt straight column plugs and curved column plugs to replace the traditional expanded wedge-shaped plugs. The performance of the proposed new plug structures under high water head is then a critical issue and attracts the attentions of engineers. This paper firstly studied the joint bearing mechanism of plug and surrounding rock mass and found that the quality and mechanical properties of the interfaces among plug concrete, shotcrete, and surrounding rock mass play a key role in the performance of plug structures. By performing geophysical and mechanical experiments, the contact state and the mechanical parameters of the interfaces were analyzed in detail and provide numerical analysis with rational input parameters. The safety evaluation is carried out through numerical calculation of plug stability under both construction and operation period. The results indicate that the allowable water head acting on columnar plugs is 3.1 to 7.4 times of the designed water head. So the stability of the new plug structure meets the design code requirement. Based on above findings, it is concluded that for the studied project, it is feasible to adopt columnar plugs to replace the traditional expanded wedge-shaped plugs. It is hoped that this study can provide reference for other projects with similar engineering background and problems.