• Journal of the Chungcheong Mathematical Society
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• v.28 no.1
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• pp.65-72
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• 2015

The (affine) development of a smooth curve in a smooth manifold M with respect to an arbitrarily given affine connection in the bundle of affine frames over M is well known (cf. S.Kobayashi and K.Nomizu, Foundations of Differential Geometry, Vol.1). In this paper, we get the generalized affine development of a smooth curve $x_t$ ($t{\in}[0,1]$) in M into the affine tangent space at $x_0$ (${\in}M$) with respect to a given generalized affine connection in the bundle of affine frames over M.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.391-399
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• 2018

In this paper, experimental study performed on steel-pipe connections for structural members of a greenhouse is presented. By those experiments performed, bending moment, deformation and stress distribution of specimens were investigated under four point bending test. The bending performance according to connection method using pin and the stretching is also investigated. The results of bending performance of the no connection specimen were compared to those of other connection specimens. The pin and stretching connection specimens showed lower banding performance than the no connection specimen. The stretching connection method was relatively higher bending performance than the pin connection specimens. According to the results, we proposed the connection method with good bending performance that can be applied to steel-pipe connection in greenhouse.

• Steel and Composite Structures
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• v.17 no.5
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• pp.573-599
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• 2014

A new type of connection for steel-concrete composite bridges was developed by the Steel Structures Laboratory of Ecole Poytechinque $F{\acute{e}}d{\acute{e}}rale$ de Lausanne. Resistance to longitudinal shear is based on the development of shear stresses in the confined interfaces which form the connection. Confinement is provided by the reinforced concrete slab which encloses the connection and restrains the uplift (lateral separation) of the interfaces by developing normal stresses. The experimental investigation of the interfaces, under static and cyclic loading, enabled the development of the laws describing the structural behaviour of each interface. Those laws were presented by the authors in previous papers. The current paper focuses on the continuity of the research. It presents the experimental investigation on the new connection by means of push-out tests on specimens submitted to static and cyclic shear loading. Investigation revealed that the damage in the connection, due to cyclic loading, is expressed by the accumulation of a residual slip. A safe fatigue failure criterion is proposed for the connection which enabled the verification of the connection for the fatigue limit state with respect to the limit of fatigue. A numerical model is developed which takes into account the laws describing the interface behaviour and the analytical expressions for the confinement effect, the latter obtained by performing finite element analysis. This numerical model predicts the shear resistance of the connection and enables to assess its fatigue limit which is necessary for the fatigue design proposed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.11a
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• pp.129-133
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• 2008

For the construction of Top-Down structures, it is crucial to have a solid connection between prefounded columns and slabs. This paper presents a new construction method for the connection when using a circular Concrete Filled Tube (CFT) as a prefounded column as an alternative to currently using wide flange type columns. The development of shear studded jackets along with a shear band suitable for the circular shape of the column has been made. The details and mechanism of the connection is explained together with the results of experiments which verified the structural integrity of the connection.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.515-520
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• 1997

This research is aimed at the development of the composite beam-column connection system by which the steel beam can be connected to the R/C column with smooth stress transfer. As the first step of the structural performance tests of the system, bearing resistance test has been carried out for actual size specimen. From the test, the connection system has been proved to take good bonding and stress transfer to the surrounding concrete with negligible relative displacements.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.2255-2262
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• 2015

Recent study about near-surface is proposed to overcome non-economic of underground railway and to reduce people's complaints of ground elevated railway. In this report, precast modular structure system replacing temporary facilities is applied to ensure the construction ability and economic feasibility. To verify the performance of connection joint between permanent structural wall and upper slab, loading test is carried out. As a result of the test, wall replacing temporary structure to slab connection is possible to transfer bending moment. By 30% increase of bending resistant performance for connection joint using coupler, coupler connection joint is more advantageous to resist bending moment compared to channel connection.

• Journal of Korean Association for Spatial Structures
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• v.7 no.3 s.25
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• pp.141-151
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• 2007

The appearance of many Glass Fiber Reinforced Plastic (GFRP) constructions look like ordinary steel construction, because GFRP has been imitated by the same way with the traditional steel's cross section as well as connection system. In terms of detachable connection, there was not enough appropriate option of GFRP connection, such as a traditional bolt connection for steel and wood structures. Most of all, from material characteristic of GFRP related to the deficient ductility, the shearstress principle of GFRP s not proper for the material property, which causes ineffective and not economic application of material. With this research problem, the innovative and detachable onnection system, which is more considered with appropriate material characteristic for FRP, is developed. Not only short time but also long time research with various connection variations is carried out.

• Journal of the Korean Society of School Health
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• v.30 no.3
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• pp.306-316
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• 2017

Purpose: The purpose of this study was to investigate the operational status and operational problems of health promoting model schools, particularly of the large-sized elementary schools in urban areas. Methods: The study analyzed the data of 14 large-sized elementary schools in urban areas selected from 85 health promoting model schools, an initiative led by the Ministry of Education from 2012 to 2014. Results: The study examined the operation process of health promoting schools in five stages; system development, needs survey & current status survey, school health policy development, program development & execution, and evaluation. In addition, the study discovered three key factors in operating health promoting schools and examined the status of each factor; connection with the curriculum, connection with the community, and consensus among members. Four problems were identified as operational problems: lack of research on faculty health issues, school physical environment and community resources, inadequate presentation of performance indicators, no close coordination in core task development and lack of linkage with the curriculum. Conclusion: It turned out the concept of health promoting school suggested by WHO was relatively faithfully realized in this study. Compared to small-sized elementary schools in rural areas, health promoting schools in this study showed better aspects overall. The connection with the community was good, but the connection with the curriculum was poor.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1056-1058
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• 2005

It shows a tendency to increase rapidly underground of the city due to the build up of the large residential districts with industrial development, so there is required the development of the connection device for underground low voltage cable with high quality & convenient for use with consideration for installation condition of the underground. Hence, We will have the development of the connection device for underground low voltage cable, which is made waterproof perfectly under the flood of the underground for the long time, is convenient for use in spite of narrow area such as manhole or handhole, and can be able to prevent the release by the vibration.

• Korean Institute of Interior Design Journal
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• v.13 no.2
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• pp.159-167
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• 2004

To realize the above concepts of underground space, several underground facilities are concentrated upon and around subway stations in harmony with underground pedestrian walkways. As a result, the reduction of transit time and pedestrian distance make it easy to get to an object. In this study, underground space is considered not just as pedestrian walkways, but as space for various activities and as a positive element in connection with its circumstances. The purpose of the study is to understand underground space's elements and develop more aesthetic and efficient design of the space to give mental composure and familiarity to users. The development of underground connection space is one of the methods to improve the quality of the whole downtown area. This paper studied the general characteristics of connection space and space improvements after spot inspections and suggested several aspects useful for substantial design as essential data for development of underground connection space.