• Steel and Composite Structures
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• v.18 no.6
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• pp.1391-1404
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• 2015

A radially retractable roof structure based on the concept of the hybrid grid shell is proposed in this paper. The single-layer steel trusses of the radially foldable bar structure are diagonally stiffened by cables, which leads to a single-layer lattice shell with triangular mesh. Then comparison between the static behavior between the retractable hybrid grid shell and the corresponding foldable bar shell with quadrangular mesh is discussed. Moreover, the effects of different structural parameters, such as the rise-to-span ratio, the bar cross section area and the pre-stress of the cables, on the structural behaviors are investigated. The results show that prestressed cables can strengthen the foldable bar shell with quadrangular mesh. Higher structural stiffness is anticipated by introducing cables into the hybrid system. When the rise-span ratio is equal to 0.2, where the joint displacement reaches the minimal value, the structure shape of the hyrbid grid shell approaches the reasonable arch axis. The increase of the section of steel bars contributes a lot to the integrity stiffness of the structure. Increasing cable sections would enhance the structure stiffness, but it contributes little to axial forces in structural members. And the level of cable prestress has slight influence on the joint displacements and member forces.

• Geomechanics and Engineering
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• v.12 no.1
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• pp.161-183
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• 2017

This paper investigates the damage identification of the concrete pile element through axial wave propagation technique using computational and experimental studies. Now-a-days, concrete pile foundations are often common in all engineering structures and their safety is significant for preventing the failure. Damage detection and estimation in a sub-structure is challenging as the visual picture of the sub-structure and its condition is not well known and the state of the structure or foundation can be inferred only through its static and dynamic response. The concept of wave propagation involves dynamic impedance and whenever a wave encounters a changing impedance (due to loss of stiffness), a reflecting wave is generated with the total strain energy forked as reflected as well as refracted portions. Among many frequency domain methods, the Spectral Finite Element method (SFEM) has been found suitable for analysis of wave propagation in real engineering structures as the formulation is based on dynamic equilibrium under harmonic steady state excitation. The feasibility of the axial wave propagation technique is studied through numerical simulations using Elementary rod theory and higher order Love rod theory under SFEM and ABAQUS dynamic explicit analysis with experimental validation exercise. Towards simulating the damage scenario in a pile element, dis-continuity (impedance mismatch) is induced by varying its cross-sectional area along its length. Both experimental and computational investigations are performed under pulse-echo and pitch-catch configuration methods. Analytical and experimental results are in good agreement.

• The Journal of the Korea Contents Association
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• v.10 no.6
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• pp.275-285
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• 2010

As we enter an era of emotional and endlessly competitive society, there has been a lot of changes happening to the styles and images of men, traditionally associated with strength and power. Today, the media is giving information on today's trendy men's styles and images to meet the growing demand by consumers, and giving appropriate gains in the process to all - both information providers and consumers. Generally speaking, the cover of a magazine represents the concept and image of the magazine. The cover model is closely tied with the symbolic image of the magazine, the current times, and what the general public wants. Therefore, research on the cover models of a lifestyle magazine has significance in that the current style trends will be able to be understood directly. The present research investigated the sexual images of men's magazine cover models. In carrying out the research, the sexual images were classified into the following: homosexual, cross sexual, metro sexual, and uber sexual. The research findings showed that uber sexual is the dominant sexual image in men's magazines in Korea, followed by metro sexual. In conclusion, the findings suggest an expansion of the traditional image of men, happening with the changes in traditional sex roles.

• Journal of Korean Academy of Nursing Administration
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• v.23 no.2
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• pp.161-169
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• 2017

Purpose: This study was a cross-sectional study done to determine the relevance and impact factors of nursing practice environment and self-esteem on critical thinking disposition in clinical nurses. Methods: A survey was conducted from March to May 2015 with self-report questionnaire. Participants were 281 registered nurses working in one tertiary hospital. Data were analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation, and multiple regression with SPSS/WIN 21.0. Results: Factors affecting the nurses' critical thinking disposition included age (F=7.23, p<.001), educational background (F=7.82, p<.001), position (F=14.95, p<.001), clinical career (F=7.66, p<.001). Further, critical thinking disposition had a positive correlation with nursing practice environment (r=.60, p<.001) and self-esteem (r=.41, p<.001). Self-esteem and nursing practice environment accounted for 43% of the variance in critical thinking disposition. Conclusion: The study findings show that critical thinking disposition is influenced by nursing foundations for quality of care and the collegial nurse-physician relations of nursing practice environment. Therefore, it's necessary to provide continuing education for clinical nurses to reconstruct the organizational culture of nurses and physician partnerships. In addition, increasing self-esteem through various motivational programs should increase critical thinking disposition.

• Journal of the Korea Concrete Institute
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• v.21 no.1
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• pp.65-74
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• 2009

Glass fiber reinforced polymer (GFRP) bars are sometimes used when corrosion of conventional reinforcing steel bar is of concern. In this study, a total of 36 beams and one-way slabs reinforced using GFRP bars were tested in flexure. Four different GFRP bars of 13 mm diameter were used in the test program. In most test specimens, the GFRP bars were lap spliced at center. All beams and slabs were tested under 4-point loads so that the spliced region be subject to constant moment. Test variables were splice lengths, cover thicknesses, and bar spacings. No stirrups were used in the spliced region so that the tests result in conservative bond strengths. Average bond stresses that develop between GFRP bars and concrete were determined through nonlinear analysis of the cross-sections. An average bond stress prediction equation was derived utilizing two-variable linear regression. A splice length equation based on 5% fractile concept was then developed. As a result of this study, a rational equation with which design splice lengths of the GFRP bars can be determined, was proposed.

• Journal of Korean Association for Spatial Structures
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• v.12 no.3
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• pp.63-70
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• 2012

In this study, the displacement-based design concept, the performance by the existing reinforced concerte column and steel reinforced concrete composite column for SRC purchased the maximum design ground acceleration improvement compared to the performance design. SRC have several advantages such as strength enhancement and high ductility. H-beam or steel tubes were used for embedded elements of the SRC composite columns. SRC cross-section for the P-M diagram and analysis on the nominal bending monent SRC designed for composite columns for disparity estimation is presented to the displacement-based seismic design. Performance improvement of the performance-based design performance targets for the design seismic displacement and design criteria for the direct displacement-based design methods and to improve the seismic performance due to the displacement coefficient method is proposed to design. SRC compared with the RC column designed to improve the performance and displacement ductility ratio displacement results in the performance design results showed significantly improved performance.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.10
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• pp.3334-3343
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• 1996

A quantitative flow visualization technique was developed to measure velocity and temperature fields simultaneously in a two-dimensional cross section of thermo-fluid flows. Thermochromic liquid crystal(TLC) particles are used as temperature sensor and velocity tracers. Illuminating a thermo-fluid flow with a thin sheet of white light, the reflected colors from the TLC particles in the flow were captured simultaneously by two CCD cameras; a 3-chip CCD color camera for temperature field measurement and a black and white CCD camera for velocity field measurement. Variations of temperature field were measured by using a HSI true color image processing system and TLC solution. The relationship between the hue values of TLC color image and real temperature was obtained and this calibration curve was used to measure the true temperature under the same camera and illumination condition. The velocity field was obtained by using a 2-frame PTV technique using the concept of match-probability to track true velocity vectors from two consecutive image frames. These two techniques were applied at the same time to the unsteady thermal-fluid flow in a Hele-Shaw cell to measure the temperature and velocity field simultaneously and some results are discussed.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.4 s.70
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• pp.395-404
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• 2005

This paper presents a reliable numerical procedure for nonlinear time-history analysis of space steel frames subjected to dynamic loads. Geometric nonlinearities of member (P-$\delta$) and frame (P-$\Delta$) are taken into account by the use of stability functions in framed stiffness matrix formulation. The gradual yielding along the member length and over the cross section is included by using a tangent modulus concept and a softening plastic hinge model based on the New-Orbison yield surface. A computer program utilizing the average acceleration method for the integration scheme is developed to numerically solve the equation of motion of framed structure formulated in an incremental form. The results of several numerical examples are compared with those derived from using beam element model of ABAQUS program to illustrate the accuracy and the computational efficiency of the proposed procedure.

• Proceedings of the Korean Society for Language and Information Conference
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• 2001.06a
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• pp.199-225
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• 2001

The main goal of this paper is to investigate and compare English, German and Korean non-head-bound-intensifiers such as English ‘x-self’, German ‘selbst’, and Korean ‘susulo, casin’. That is, this paper is mainly concerned with the semantic domain where the respective contributions of the expressions in question overlap. The phenomenon under discussion with the label “intensifiers” is regarded as universal, which provides the ground of the comparative/contrastive or semi-cross-linguistic study of this paper. Not only the semantic concept of intensification by these expressions but also the combination of grammatical features or syntactic behaviours thereof seem to have highly invariant common denominators among the wide varieties of languages, even if they come from apparently different language families. In comparing English, German and Korean intensifiers, this paper is interested in the more general features of the expressions in question rather than some language-specific idiocyncracies. Intensifiers work similarly not only in English and German, but also in Korean. Each of three languages under investigation provides some sort of a safegard against confusing instances and misleading judgements on the issues under discussion. Morphologically, however, English expressions in question agree with their rele-vant NP in number, gender and person. Whereas German and Korean counterparts do not have such specific morphological properties. Intensifiers in their non-head-bound-use are subject-oriented, just as in their head-bound use. Non-head-bound-intensifiers differ from head-bound-intensifiers mostly in their syntactic behaviours or distributional properties, whereas they share the semantic domain “intensification” regarding relevant subject-NP. They introduce an ordering and distinguish center and periphery, and ‘self-involvement (directness of involvement)’seems a additional possible characterisation of the relevant dimension of these intensifiers in common. An assertion of identity also can be reg

• The Journal of the Korean dental association
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• v.55 no.12
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• pp.842-849
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• 2017

The term, 'crossed occlusion' implies clinical situation in which the residual teeth in one arch have no contact with those in the antagonistic arch, resulting in the collapse of occlusal vertical dimension. The treatment goal of this pathologic condition is restoration of the collapsed vertical dimension and stabilization of abnormal mandibular position. Previously, konus removable prostheses or tooth supported overdentures were suggested to solve crossed occlusion. Nowadays, dental implants have been used for definitive support to solve this problem. In this case report, a 65 years old female patient had a crossed occlusion, in which the maxillary posterior residual teeth and mandibular anterior residual teeth cross. Interim removable and fixed dental prostheses were used to confirm the proper vertical and horizontal jaw relation. After that, the mandibular posterior edentulous region was restored with implant-supported fixed dental prostheses. Computer tomography guided implant surgery was performed according to the concept of the restoration-driven implant placement. The maxillary anterior edentulous region was restored with Kennedy class IV removable prosthesis, considering the patient's economic status. The patient's jaw position and prostheses have been well maintained at the follow-up after 6 months of definitive restoration. The antero-posterior crossed occlusion problems appeared to be effectively solved with the combination of removable in one arch and implant-supported fixed prostheses in the other.