• Structural Engineering and Mechanics
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• 제17권2호
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• pp.245-266
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• 2004

Incremental launching method is one of the highly competitive techniques for construction of concrete bridges. It avoids costly and time consuming form work and centralizes all construction activities in a small casting yard, thus saving in cost and time against conventional bridge construction. From the quality point of view, it eliminates the uncertainty of monolithic behaviour by allowing high repetitiveness and industrial environment. But, from analysis and design point of view, the most characteristic aspect of incrementally launched bridges is that, it has to absorb the stresses associated with the temporary supports that are gradually taken on by the deck during its launch. So, it is necessary to analyse the structure for each step of launching which is a tedious and time consuming process. Effect of support settlements or temperature variation makes the problem more complex. By using transfer matrix method, this problem can be handled efficiently with minimal computational effort. This paper gives insight into method of analysis, formulation for optimization of the structural system, effect of support settlement and temperature gradient, during construction, on the stress state of incrementally launched bridges.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 춘계학술대회 논문집
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• pp.364-367
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• 2003

In this paper, a realistic launching method for railway bridge is developed. When bridge is launched, it might experience the excessive deflection. Launching method with cable-stayed scheme is developed to control the deflection. The developed method was applied to the launching of an actual bridge. This study results show that bridges can be launched with favorable deflection by the proposed method.

• Structural Engineering and Mechanics
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• 제24권6호
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• pp.741-764
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• 2006

The time-dependent analysis of prestressed concrete bridges built adopting the incremental launching technique is presented. After summarizing the well known results derived from the elastic analysis, the problem is approached in the visco-elastic domain taking into account the effects consequent to the complex load history affecting the structure. In particular, the effects produced by prestressing applied both in the launching phase and after it and by application of imposed displacements and of delayed restraints during the launching phases are carefully investigated through a refined analytical procedure. The reliability of the proposed algorithm is tested by means of comparisons with reference cases for which exact solutions are known. A case study of general interest is then discussed in detail. This case study demonstrates that a purely elastic approach represents a too crude approximation, which is unable to describe the specific character of the problem.

• 한국공간정보시스템학회:학술대회논문집
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• 한국공간정보시스템학회 2005년도 추계학술대회
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• pp.239-244
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• 2005

In North Korea, there has been the considerable loss of human lives every yew due to the deficiency of foods. Thus, in order to reduce such damages, a research project should be launched to provide various information for cooperation with North Korean government, and to develop proper agricultural management system. Furthermore, based on the water resources information map generated by KOWACO (Korea Water Resources Corporation) and the environmental information system developed by MOE (Ministry of Environment), an agricultural information infrastructure of North Korea and a management system need to be effectively performed. Therefore, this research is mainly to develop the Agricultural Information Management System of North Korea (NKAIMS), which can collect, manage and analyze agricultural information and water resources utilization status of North Korea, and further support to make relevant decisions and establish the agricultural land-use plans. This research has three phases. The major outcome of the first phase is collecting the agricultural and water resources utilization data such as soils, rivers, streams, collective farms, etc., designing and building database, and developing integrated management system considering the users' requirements. The main work of the second phase is improving and reinforcing database such as adding the information of dams, land-over data, bridges, tunnels, satellite images, etc., inspecting and renewing such as importing detail attribute information of reservoirs, and improving system for more conveniently using. The third phase will be to supplement more useful functions such as statistic analysis, continually inspecting and improving database, and developing web-based system. The product of this research supports collecting and analyzing relevant data to facilitate easier agricultural activities and support effective decision making for food production in the preparation of unification. Moreover, through designing database considering sharing information and system expendability, it can support systematic data usability of agricultural information and save cost for data management.

• 대한토목학회논문집
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• 제28권4A호
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• pp.487-495
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• 2008

본 연구에서는 압출가설시 압출노즈와 가설거더 시스템의 거동에 대한 압출노즈의 휨강성비, 단위중량비 및 길이비의 영향을 살펴보고, 압출과정에서 발생하는 부모멘트 및 정모멘트를 최소화할 수 있는 압출노즈에 대한 최적조건을 도출하고자 하였다. 또한, 도출된 최적조건을 사용하여 압출노즈의 단위중량비와 길이비의 관계식을 유도하고 압출가설시에 발생하는 절대최대 정모멘트 및 부모멘트의 산정식을 제시하였으며, 연속거더교량의 압출가설시에 사용되는 압출노즈의 최적설계 방안을 제안하였다. 가장 이상적인 압출노즈의 설계는 절대최대 부모멘트를 최소화하면서 절대최대 정모멘트의 발생을 억제할 수 있는 단위중량비 0.167, 길이비 0.836을 적용한 경우임을 확인하였다.

• Spatial Information Research
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• 제13권4호
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• pp.365-372
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• 2005

북한에서는 매년 기근 때문에 상당한 인명 손실이 있어왔다. 이러한 손실을 줄이기 위해 북한 정보와 함께 다양한 정보 공유를 통해 조사 연구가 필요한 실정이다. 또한, 그에 맞는 농작물 관리 시스템의 개발이 필요하다. 이 연구는 북한의 농작물 관리 시스템의 개발을 목적으로 하고 있다. 이 시스템은 북한의 수자원의 이용 상태뿐만 아니라, 농작물에 관한 정보를 수집하고, 관리하며, 분석하는 기능을 담고 있다. 그리고 이 시스템은 최종적으로 농작물 관리에 필요한 토지 이용 계획을 수립하고, 관련된 의사 결정을 하는데 도움을 준다. 첫 번째 결과물은 농작물과 수자원 관련 데이터를 수집하고 데이터베이스로 구축한 다음 사용자 요구에 맞춰 통합 시스템을 구축하는 것이다. 두 번째는 댐, 토지 피복도, 다리, 터널, 위성영상 등의 데이터를 이용하여 데이터베이스를 업데이트하고, 강화시킨다. 세 번째는 통계분석, 지속적인 데이터베이스 갱신, web-based 시스템으로 개발 등과 같은 유용한 기능 등을 추가하는 것이다. 본 연구의 결과물은 농업활동을 더 용이하게 하기 위해 연관된 데이터를 수집하고 분석하게 해준다. 그리고 식량 생산을 위해 효과적인 의사결정을 하게 한다. 게다가, 정보 공유를 통해, 농작물 관련 정보를 유용하게 사용하고 데이터 관리의 비용을 줄일 수 있다.

• 미술이론과 현장
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• 제2호
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• pp.27-48
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• 2004

Robert Rauschenberg's artistic career has often been regarded as having reached its culmination when the artist won the first prize at the 1964 Venice Biennale. With this victory, Rauschenberg triumphantly entered the pantheon of all-American artists and firmly secured his position in the history of American art. On the other hand, despite the artist's ongoing new experiments in his art, the seemingly precocious ripeness in his career has led the critical discourses on Rauschenberg's art to the artist's early works, most of which were done in the mid-1950s and the 1960s. The crux of Rauschenberg criticism lies not only in focusing on the artist's 50's and 60's works, but also in its large dismissal of the significance of the imagery that the artist employed in his works. As art historians Roger Cranshaw and Adrian Lewis point out, the critical discourse of Rauschenberg either focuses on the formalist concerns on the picture plane, or relies on the "culturalist" interpretation of Rauschenberg's imagery which emphasizes the artist's "Americanness." Recently, a group of art historians centered around October has applied Charles Sanders Peirce's semiotics as art historical methodology and illuminated the indexical aspects of Rauschenberg's work. The semantic inquiry into Rauschenberg's imagery has also been launched by some art historians who seek the clues in the artist's personal context. The first half of this essay will examine the previous criticism on Rauschenberg's art and the other half will discuss the artist's 1955 work Rebus, which I think intersects various critical concerns of Rauschenberg's work, and yet defies the closure of discourses in one direction. The categories of signs in the semiotics of Charles Sanders Peirce and the discourse of Jean-Francois Lyotard will be used in discussing the meanings of Rebus, not to search for the semantic readings of the work, hut to make an analogy in terms of the paradoxical structures of both the work and the theory. The definitions of rebus is as follows: Rebus 1. a representation or words or syllables by pictures of object or by symbols whose names resemble the intended words or syllables in sound; also: a riddle made up wholly or in part of such pictures or symbols. 2. a badge that suggests the name of the person to whom it belongs. Webster's Third New International Dictionary of the English Language Unabridged. Since its creation in 1955, Robert Rauschenberg's Rebus has been one of the most intriguing works in the artist's oeuvre. This monumental 'combine' painting($6feet{\times}10feet$ 10.5 inches) consists of three panels covered with fabric, paper, newspaper, and printed reproductions. On top of these, oil paints, pencil and crayon drawings connect each section into a whole. The layout of the images is overall horizontal. Starting from a torn election poster, which is partially read as "THAT REPRE," on the far left side of the painting. Rebus leads us to proceed from the left to the right, the typical direction of reading in a Western context. Along with its seemingly proper title. Rebus, the painting has triggered many art historians to seek some semantic readings of it. These art historians painstakingly reconstruct the iconography based on the artist's interviews, (auto)biography, and artistic context of his works. The interpretation of Rebus varies from a 'image-by-image' collation with a word to a more general commentary on Rauschenberg's work overall, such as a work that "bridges between art and life." Despite the title's allusion to the legitimate purpose of the painting as a decoding of the imagery into sound, Rebus, I argue, actually hinders a reading of it. By reading through Peirce to Rauschenberg, I will delve into the subtle anxiety between words and images in their works. And on this basis, I suggest Rauschenberg's strategy in playing Rebus is to hide the meaning of the imagery rather than to disclose it.