• Journal of the Korean Geotechnical Society
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• v.16 no.1
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• pp.191-201
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• 2000

In this study, the earth retaining structure using a row of piles considering plastic flow of the ground is suggested for shallow excavation works instead of conventional anchored sheet-pile wall method in the marine clays with high groundwater level. The behavior of the earth retaining structure using a row of piles is precisely observed during excavation by inclinometer and piezometer installed in opposite to the excavation side. As a result of field measurement, it was found that the behaviors of the piles and the soil were influenced mainly by slope of excavation face, interval ratio of piles, fixity condition of pile head, and stability number, etc. The earth retaining structure using a row of piles is ascertained for workability, stability, and economical construction on the soft ground having no adjacent structures.

• Steel and Composite Structures
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• v.5 no.6
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• pp.443-458
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• 2005

Steel angles are widely used in roof trusses as web and chord members and in lattice towers. Very often angle members are connected eccentrically. As a result, not only an angle member is under an axial force, but it is also subject to a pair of end eccentric moments. Moreover, the connection at each end provides some fixity so neither pinned nor the fixed end represents the reality. Many national design codes allow for the effects due to eccentricities by modifying the slenderness ratio and reducing the compressive strength of the member. However, in practice, it is difficult to determine accurately the effective length. The concept behind this method is inconsistent with strength design of members of other cross-sectional types such as I or box sections of which the buckling strength is controlled by the Perry constant or the initial imperfection parameters. This paper proposes a method for design of angle frames and trusses by the second-order analysis. The equivalent initial imperfection-to-length ratios for equal and unequal angles to compensate the negligence of initial curvatures, load eccentricities and residual stresses are determined in this paper. From the obtained results, the values of imperfection-to-length ratios are suggested for design and analysis of angle steel trusses allowing for member buckling strength based on the Perry-Robertson formula.

• English & American cultural studies
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• v.14 no.2
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• pp.77-96
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• 2014

As the cyberspace several decades ago created a cyber fiction fever, the augmented reality as the future of imagination can generate another kind of literary genre and new social ambiance where books tend to come to life more realistically. This newly created "smart fiction," "smart movies," and "smart environment" will be full of fun, hopes and conveniences. But addiction to smart kinds will create unwanted dangerous plethora like ghost-like avatars, wild animals and Farid due to the limitations of human control over hi-technology. If so, the adventures we plan to take will turn fantasy into horror in no time. Instead of loving new scientific things blindly, the emphasis hereafter must be put rather on the potentially negative aftermaths of the new innovative technology. Some viewers after watching the film Avatar are still suffering from the syndrome called "avatar blues," a homesick for Pandora. After their experiencing of the experimental 3D effects in books and media, audience and readers are required to actively deal with the increased lack of the darker cave which the comparatively unsatisfactory present can never fill with fixity and limit. Like the prevention against the addictive online game or the manual of 3D television or 3D printer, the extreme off-limits and safety zone for this virtually and expendably subverting technology must be seriously reviewed by community before using and adopting it. Also, these technologically expanded and augmented environments must be prudently criticized by the in-depth study of literature just as cyber space begun by Gibson's cyber fiction and its criticism.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.3
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• pp.293-300
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• 2015

In this study, a series of forced vibration testing and ambient vibration measurement were performed at a lowrise masonry-infilled reinforced concrete frame structure before and after seismic retrofit and its dynamic properties were extracted using system identification techniques. Also, analytical models which show similar dynamic properties to the measures ones were constructed. The system identification results showed that damping ratios in x direction along which the dampers were installed has been increased. From the comparison between the analytical models, the effective stiffness of post-installed member and post-reinforced members(shear walls and damper frames) were only 50% of gross sectional stiffness of the members, which indicates that the these members were not fully integrated with the existing structure or members. In addition, support condition of post-installed footing has to be pinned in y direction to match the dynamic properties, which is seemingly caused by the change of fixity of the soil due to the installation of new footing.

• English Language & Literature Teaching
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• v.13 no.3
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• pp.117-132
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• 2007

Playwright Eugene O'Neill's expressionistic text-based approach to The Emperor Jones, with an emphasis on fixity, was at odds with African American actor Charles Gilpin's improvisational performance technique, stressing rupture, spontaneity, and discontinuity. The contemporary avant-garde performance troupe The Wooster Group likewise produces subversive and interrogative forms of identity in performing the play, which challenge the normative approach to gender, race, and an imagined orientation. The historical foundation of subversion and destabilization laid by O'Neill and Gilpin were manifold in the Wooster Group's production of The Emperor Jones, and not only formed a backdrop to it but also played a central role in the group's representation of race and even gender on the stage. In this essay, I use O'Neill's play, The Emperor Jones, a crucial example of racialized fantasies of identification, to explore how the modernist stage through the performances of Gilpin and The Wooster Group constructed racialized subjects of both its performers and audiences. Gilpin and the Wooster Group's strategies each shared a similar complexity in the portrayal of black identity in performance. Offering an examination of how ideologies of race and gender overlap in The Emperor Jones, I hope to show how each performance signifies a range of subversions and differences simultaneously and sometimes oppositionally that needs to be explored both holistically and in detail to offer a fuller picture of these remarkable attempts. Through this approach, I examine Gilpin's creative adaptations of O'Neill's text and illuminate how it is that the Wooster Group's appropriative use of blackface in their performance has come to gain critical acceptance.

• Computational Structural Engineering
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• v.5 no.1
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• pp.119-132
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• 1992

The objective of this study is to perform extensive parametric studies of the lateral-torsional buckling of short 1-beams under repeated loadings, and to gain a further insight into the lateral-torsional beam buckling problem. A one-dimensional geometrically (fully) nonlinear beam model is used, which includes superposed infinitesimal transverse warping deformation in addition to finite torsional warping deformation. A multiaxial cyclic plasticity model is also implemented to better represent cyclic metal plasticity in conjunction with a consistent return mapping algorithm. The general response for the lateral-torsional buckling of short I-beams under repeated loadings is examined through several parametric studies around the standard case : the material yield strength, the yield plateau, the strain hardening, the kinematic hardening, the residual stresses, the load eccentricity with respect to the shear center, the height of the load with respect to the cross-section of the beam, the location of the load along the length of the beam, the dimensions of the cross-section of the beam and the fixity of the supported end remote from the load.

• Journal of Biosystems Engineering
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• v.29 no.2
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• pp.151-158
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• 2004

This research was conducted to study the offensive odor adhesion efficiency of filter bed materials using the experimental column that was designed and constructed in this work. The offensive odor adhesion experiment was conducted using mixture of high physical adhesion efficiency material, and the fixity of deodorization microorganism of selected filter bed material was tested using ammonia exclude microorganism A4-2 and sulfur oxidation microorganism S5-5.2 those were cultured at the Agricultural Chemical Department of Chungnam National University, and deodorization efficiency of selected filter bed material mixture was tested. Followings are summary of these tests results. 1) Amount of elimination of the offensive odor gas ammonia and hydrogen sulfide per unit volume were 0.054 and 0.016 $\ell$/㎤ in rice hull, 0.01 and 0.004 $\ell$/㎤ in rice straw, 0.158 and 0.01 $\ell$/㎤ in coconut, 0.014 and 0.02 $\ell$/㎤ in perlite, 0.004 and 0.003 $\ell$/㎤ in high road ball, and 0.112 and 0.015 $\ell$/㎤ chaff of pine, respectively. 2) Amount of elimination of offensive odor gas of ammonia and hydrogen sulfide per unit vloume were 0.079 and 0.016 $\ell$/㎤ in mixture 1, 0.045 and 0.014 $\ell$/㎤ in mixture 2, 0.123 and 0.017 $\ell$/㎤ in mixture 3, 0.055 and 0.016 $\ell$/㎤ in mixture 4, 0.031 and 0.015 $\ell$/㎤ in mixture 5, and 0.111 and 0.020 $\ell$/㎤ in mixture 6, respectively. 3) The offensive odor elimination microoraganism inoculated to the mixture of chaff of pine (70%) and pert (30%) showed the elimination efficiency of 99.06% and 96.61% against the ammonia and hydrongen sulfide, respectively, during 24 hours period.

• Geotechnical Engineering
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• v.7 no.2
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• pp.67-82
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• 1991

When bridge abutments are constructed on pile foundations in unstable slope, horizontal deflections may be developed in the piles and the abutments due to lateral soil movements arisen from backfills. In most of the above mentioned cases, the piles are situated in a soft layer where lateral earth pressures are developed between the piles and the soils. The undesirable lateral earth pressures decreases the stability of the piles. However, the piles may have a preventive effect against lateral soil movements and improve the stability of the slope. For the stability problem of such slope containing piles in a row, two kinds of analyses for the slope-stability and the pile-stability have to be performed. The whole stability of bridge abutments on pile foundation can be obtained only by the stabilization for both the slope and the piles. A reasonable analytical method for the bridge abutments on pile foundation was established in this study By use of the analytical method for an example, several factors which influence affect the stability of bridge abutment were investigated. Finally, for the bridge abutment subjected to lateral deflections damage, the fixity condition of pile head was investigated.

• Computers and Concrete
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• v.1 no.3
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• pp.325-354
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• 2004

Slabs in buildings and bridge decks, which are restrained against lateral displacements at the edges, have ultimate strengths far in excess of those predicted by analytical methods based on yield line theory. The increase in strength has been attributed to membrane action, which is due to the in-plane forces developed at the supports. The benefits of compressive membrane action are usually not taken into account in currently available design methods developed based on plastic flow theories assuming concrete to be a rigid-plastic material. By extending the existing knowledge of compressive membrane action, it is possible to design slabs in building and bridge structures economically with less than normal reinforcement. Recent research on building and bridge structures reflects the importance of membrane action in design. This paper describes the finite element modelling of membrane action in reinforced concrete slabs through optimisation of a simple concrete model. Through a series of parametric studies using the simple concrete model in the finite element simulation of eight fully clamped concrete slabs with significant membrane action, a set of fixed numerical model parameter values is identified and computational conditions established, which would guarantee reliable strength prediction of arbitrary slabs. The reliability of the identified values to simulate membrane action (for prediction purposes) is further verified by the direct simulation of 42 other slabs, which gave an average value of 0.9698 for the ratio of experimental to predicted strengths and a standard deviation of 0.117. A 'deflection factor' is also established for the slabs, relating the predicted peak deflection to experimental values, which, (for the same level of fixity at the supports), can be used for accurate displacement determination. The proposed optimised concrete model and finite element procedure can be used as a tool to simulate membrane action in slabs in building and bridge structures having variable support and loading conditions including fire. Other practical applications of the developed finite element procedure and design process are also discussed.

• Journal of the Korean association of regional geographers
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• v.23 no.2
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• pp.288-310
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• 2017

This paper aims to provide a conceptual framework to see the special zones in East Asia in relation to the territorialities of the state. For this, it will introduce Aihwa Ong's notion of 'spaces of exception', and provide some critical discussions on it. Unlike Ong, I do not see the spaces of exception as an outcome of neoliberal changes of the state. Instead, I propose to see the special zones in terms of the internal limitations of the modern state territoriality. In particular, I try to theorize the special zones in relation to the dialectics of the contradictory relations between mobility and fixity inherent in the territoriality of the modern nation state. In addition, it will be suggested to see special zones as an essential part of the spatiality of the East Asian developmental states, given the spatio-temporal contexts of the East Asian capitalist development. On the basis of these theoretical discussions, this paper will divide the special zones that have been developed in East Asia since the 1960s into 3 different types, including 1) developmentalist special zones, 2) neo-liberal special zones, and 3) special zones for transition, and discuss their characteristics.