• Journal of Korean Society for Atmospheric Environment
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• v.16 no.E
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• pp.47-57
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• 2000

This study focuses on the investigation of the effects of windspeed and particle size on the dust control characteristics inside a test dome built in the Port of Inchon to reduce the fugitive dust originating from the handling of animal feed stuff in the open pile area. The flow field inside the test dome and the trajectories of the particles were calculated using a commercial CFD code, FLUENT, assuming that the animal feed stuff handling activity took place inside the test dome. It was found from the simulation results that high windspeed and small particle size give rise to the increase in both the escaped fraction and the suspended fraction of the particles emitted from the animal feed stuff handing activity. Here, high escaped fraction represents the high possibility of fugitive dust problem outside the test dome, whereas high suspended fraction means the high possibility of severe dust pollution inside the test dome. Ore simulation results clearly show that the existing test dome was not designed properly to meet the proposed goal, low escaped fraction and low suspended fraction. Hence, we suggest the need of an efficient ventilation system inside the dome to control the dust.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.706-710
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• 2008

The experiment of dome port cover under shock impact is performed with shock tube. The dome port cover blocked intake air duct up from the solid propellant during air breathing vehicle speed reach Mach 2.0. When the air breathing vehicle reach Mach 2.0, the inlet cover is removed and the dome port cover is broken to pieces by detonator or pressure of inlet air. Thus the dome port cover not only must stand the pressure of combustion chamber but also easy to break from the RAM pressure. In this study, a fracture evaluation on the $Al_2O_3$ ceramic spherical dome and circular plate port under impact has been presented. Ceramic were supported by the rigid body and a couple of O-ring. The Mooney-Rivlin model have been used to describe behaviors of both O-ring. And spherical dome and circular plate fracture results of the LS-DYNA code using Johnson-Holmquist(JH-2) constitutive equation was compared.

• Structural Engineering and Mechanics
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• v.73 no.4
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• pp.397-405
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• 2020

In this study size optimization of large-scale dome structures with dynamic constraints is presented. In the optimal design of these structure, the Jaya algorithm is used to find minimal size of design variables. The design variables are the cross-sectional areas of the steel truss bar elements. To take into account the constraints which are the first five natural frequencies of the structures, the finite element analysis is coded in Matlab programs using eigen values of the stiffness matrix of the dome structures. The Jaya algorithm and the finite elements codes are combined by the help of the Matlab - GUI (Graphical User Interface) programming to carry out the optimization process for the dome structures. To show the efficiency and the advances of the Jaya algorithm, 1180 bar dome structure and the 1410 bar dome structure were tested by taking into the frequency constraints. The optimal results obtained by the proposed algorithm are compared with those given in the literature to demonstrate the performance of the Jaya algorithm. At the end of the study, it is concluded that the proposed algorithm can be effectively used in the optimal design of large-scale dome structures.

• Journal of Korean Foot and Ankle Society
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• v.5 no.2
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• pp.149-155
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• 2001

Purpose: To evaluate the clinical results of Mitchell osteotomy and proximal metatarsal dome osteotomy in hallux valgus deformity. Materials and Methods: From January 1993 to June 2000, 28 cases (17 patients) with hallux valgus deformity who underwent Mitchell osteotomy were categorized as group I, 26 cases (16 patients) who underwent proximal metatarsal dome osteotomy were categorized as group II. We analyzed clinical results according to preoperative and postoperative clinical functional analysis and objective comparison of correction angle between two groups. Results: The average hallux valgus correction in the Mitchell osteotomy group went from $36^{\circ}$ to $11^{\circ}$, and in the proximal metatarsal dome osteotomy group, the hallux valgus angle was reduced from $32^{\circ}$ to $6^{\circ}$. The intermetatarsal angle in the Mitchell osteotomy group was corrected from $13^{\circ}$ to $9^{\circ}$, and in the proximal metatarsal dome osteotomy group the intermetatarsal angle was reduced from $14^{\circ}$ to $7^{\circ}$. Although, proximal metatarsal dome osteotomy group have shown better correction angle and radiographic results in the correction of hallux valgus angle and intermetatarsal angle but, all patients in the Mitchell osteotomy and proximal metatarsal dome osteotomy groups had no statistically significant differences of clinical functional results between two groups. Conclusion: In our studies, the proximal metatarsal dome osteotomy applied to. hallux valgus deformity was found as a good radiographic results than Mitchell osteotomy, but there were no differences between the two operations in terms of functional satisfaction.

• Journal of architectural history
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• v.30 no.4
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• pp.41-52
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• 2021

This study examines the Gyeongju Seokguram Grotto restoration project (1961-1962) by architect Kim Chung Up (1922-1988) and introduces the documents he wrote at the time of planning. The study highlights Kim's Plan attempt to adopt Buckminster Fuller's idea of the Geodesic Dome, while inheriting the architect Pai Ki Hyung's previous design plan which was nullified. As Seokguram Grotto's water leak and deterioration issues have been brought up, the four-times survey was carried out by experts team between 1958 and 1960, under Ministry of Education's direction. Pai designed an initial restoration plan based on the survey's result, which was a double-dome structure with a concrete film on the outer periphery as a way to protect Seokguram Grotto in January 1961. However, as drawbacks, such as the heavy load of the concrete dome, and non-installation of entrance hall, have been indicated in the review process, the Cultural Properties Committee rejected the plan. Subsequently, Kim was appointed as the supervisor of the second restoration project. Kim drew up a process management schedule to be implemented from August 1961 to December 1963 and designed the conception plans for the second restoration design. This study analyzes Kim's Plan by examining sketches, site plans, floor plans, and sections. Kim planned to maintain the idea of the double-dome structure proposed by Pai while applying Buckminster Fuller's idea of the Geodesic Dome. Kim planned to lighten the dome structure by applying a steel-frame Geodesic Dome so that the dome structure could be supported by its own. The study is expected to reclaim the omitted parts from Seokguram Grotto's historical description and Kim's careers.

• Journal of Korean Association for Spatial Structures
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• v.14 no.1
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• pp.85-91
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• 2014

The purpose of this paper is to study comparative of dynamic instability characteristic of Geiger-typed cable dome structures by load condition, which is well-known among the cable dome structures that are the lightweight hybrid structure using compression and tension element continuously. Dynamic buckling process in the phase plane is very important thing for understanding why unstable phenomena are sensitively originated in nonlinear dynamic by various initial conditions. But there is no paper for the dynamic instability of hybrid cable dome by Sinusoidal Excitations, many papers which deal with the dynamic instability for shell-structures under the step load have been published. As a result of Geiger-typed cable dome, which shows chaotic behavior in dynamic nonlinear analysis with initial imperfection.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.10
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• pp.2634-2645
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• 1993

Dome structures of pressure vessels subjected to internal pressure are usually analyzed by linear elastic theory assuming small deformation. Geometric and material nonlinear behaviors appear in actual dome structures because of large deformation and loads exceeding yield strength. In this paper, linear and nonlinear analyses were performed for various hemispherical and torispherical domes to check the effects of geometric and material nonliearity on the stress and displacement by the finite element method. The effect of the geometric nonlinearity decreased the stress levels a lot for very thin general torispherical domes, which enables more realistic and effective design. The material nonlinear effects are negligible for hemispherical and optimum torispherical domes, and those are large for most of the general torispherical domes.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.04a
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• pp.295-302
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• 1999

This paper is the experimental and analytic of reinforced concrete hemisphere dome under vertical load. It is described that when the reinforced concrete hemispherical dome supported on cylindrical wall is loaded vertically, how the opening part of dome will behave mechanically The experimental and analytic model is a Hemispherical dome with opening and the meridian angle of opening is 76$^{\circ}$at the center of sphere under concentrated load around the opening, but this is reinforced by a ring is sufficient stiffness. The diagrams of crack development are represented to understand the behavior of the reinforced concrete hemispherical dome. The method of crack analysis will be applied the rigid element spring model. The rigid element spring model is a new discrete element analysis, each divided element is assumed by rigid elements without deformation which is interconnected with elasto-plastic spring system.

• 한국공간정보시스템학회:학술대회논문집
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• 2004.05a
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• pp.83-88
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• 2004

First author proposed a proportioning method for member sections of a single layer reticulated dome subjected to uniform and non-uniform load without any geometrical initial imperfection, and discussed the validity and effectiveness of the method which was based on linear buckling stress and a knock down factor. However, buckling of a single layer reticulated dome is strongly affected by initial imperfection. It is well known that geometrical initial imperfections reduce the nonlinear buckling capacity of a single layer raticulated dome. Thus, structural engineers may be recommended to reflect the effects of geometrical initial imperfections in proportioning member sections. In this paper, firstly, the presented proportioning method by first author is applied to dome without consideration of any imperfections and the thickness and diameter of each member are determined. Secondly, the load bearing capacities of the proportioned domes are checked with the imperfection, by the inelastic buckling analysis.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.119-120
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• 2011

Dome structure to form a space-efficient, applied a lot of beautiful buildings with structural systems, as well as a large space structure in the form of new residential lots have been applied. And domestic demand for housing in the dome with increasing dome house using various materials, are becoming commonplace. But now the Dome House is mainly used in construction steel, wood, stone, FRP construction and building materials per unit area and the high cost, long construction time, energy efficiency, has some disadvantages such as degradation. And structural strength of the structure is weak, the natural ingredients used come from natural damage is so big. In addition, demolition of buildings in trouble when handling the environmental problems has emerged. Recently expanded polystyrene to improve these problems by using the various approaches and research is being attempted and there.