• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.553-558
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• 2001

Recent destructive seismic events demonstrated the importance of mitigating human casualties and serious property damages in design and construction of structures. The Korean Bridge Design Specifications (1992) adopted seismic design requirements based on the AASHTO specification, and minor modification was made in 2000. The longitudinal steel connection of reinforced concrete bridge column is sometimes practically unavoidable. The longitudinal reinforcement details affect seismic performance such as flexural failure and shear failure. This research aims to develop longitudinal steel connection details with confinement steel by experimental study for seismic performance of reinforced concrete bridge columns. Quasi-static test under three different axial load levels was conducted for 12 spiral column specimens. All the column specimens had the same aspect ratio of 3.5. The column specimens were transversely reinforced with spiral and with five different longitudinal steel connection. The final objective of this study is to suggest appropriate longitudinal reinforcement connection details for the limited ductility design concept and improve construction quality.

• Journal of the Korean School Mathematics Society
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• v.15 no.1
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• pp.199-214
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• 2012

Stochastic independence of events is not only important concept but useful role in statistics and probability. In this paper, we investigate and analyze the definition of stochastic independence used in the middle and high school mathematics education course. and We investigated that students know concept of independent events. As a result, students was a lack of understanding about the concepts associated with independence of events. and the connection between concepts associated with independent of events were partially. Also, Connections between lower-level concepts and high-level concepts can be done well so teaching-learning was needed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.2
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• pp.231-241
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• 1994

To overcome the limit of a point-point connection type service which is common to the ISDN bearer services, a new concept of network element, Service Node, which can provide multiparty connections and control the teleservices on those connections is proposed. This will support conference type multiparty multimedia services among normal ISDN subscribers. In this paper, as a primary study on this concept, we deduce some attributes of the general conference type services and examine the methods and procedures to provide that kind of services through the ISDN. Based on this study, we also define the general requirements and basic structure for the Service Node realization, thus give shape to the concept of it.

• Journal of Applied and Pure Mathematics
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• v.5 no.1_2
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• pp.9-22
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• 2023

In this paper, the connection and convergence between mathematics and science (physics) concepts were investigated. In addition, methods to closely analyze the degree of mathematics and science (physics) learning were looked into. Furthermore, methods to express and analyze the learning states of individual learners were investigated and a plan to organize educational programs was sought.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.713-717
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• 2001

This paper focuses on a network model for GCTs which can be used to investigate high power circuits with or without using RC-snubbers. The series connection of GCTs is commonly applied in the high power inverter field. Here expensive and space-consuming snubbers are applied, to overcome the problem of an asymmetric distribution of the blocking voltage among the single GCTs. As an alternative to large snubbers, a new active gate drive concept is proposed and investigated by simulation.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.09a
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• pp.155-162
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• 2003

The evolved energy concept has been demonstrated to fir the seismic evaluation of various steel connection details with the objective basis. For this, the strain energy stored in the structural system obtained from the experimental database has been normalized by that of a benchmark system. In this notion, the ideal elastic-perfectly plastic structural system has been assumed as a benchmark. In addition, the attempt shows that those previously peformed experimental database can be recycled to have further significance.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.9
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• pp.1772-1781
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• 1994

The concept of Service Node as the network element which can provide the multiparty multimedia services based on the ISDN was presented in last study. In this study, a multiparty connection service system(Service Node and terminals) was designed using the concepts, procedure, function, and structure of Service Node given above. Based on this, a small scale experimental model giving multiparty call connection control and voice service control function was implemented and tested, which proved the applicability of the concept and validity of the procedure of the Service Node. The experimental model of service system for 4 subscriber capacity was composed of a Service Node emulator and terminals with general S-interface card. The goal of implementation and testing was concentrated of the verification of the proposed functions and procedures of service system and the test results told us that the proposed concept is adequate.

• Journal of the Korean School Mathematics Society
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• v.14 no.2
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• pp.199-213
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• 2011

The factors contributing to learning can be broadly classified into four different groups; Learner's characteristic variable, Instructor's characteristic variable, Learning task characteristic variable and environmental characteristic variable. And the first thing we need to do here is understanding of learner's characteristics among those factors in order to devise a plan for education. Accordingly, the purpose of this study is to find out what impact the affective traits (self-concept learning habits learning attitude), one of the learner's features, have on the mathematics-learning achievement and to seek for a good teaching method with reference to elementary school students' learning accomplishments and attitudes. For this, a questionnaire survey was conducted of 78 students of two fifth-grade classes in an elementary school located in South Chungcheong Province in this study. In consequence, it has been shown that the mathematics-learning achievement has the greatest relevance to the self-concept in connection with mathematics followed by the self-concept in connection with learning, the learning habits relating to mathematics, the attitude towards mathematics, the learning habits concerning studies and the attitude towards learning.

• Bulletin of the Korean Mathematical Society
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• v.35 no.4
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• pp.641-652
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• 1998

Chung and et al. ([2].1991) introduced a new concept of a manifold, denoted by $^{\ast}g-SEX_n$, in Einstein's n-dimensional $^{\ast}g$-unified field theory. The manifold $^{\ast}g-SEX_n$ is a generalized n-dimensional Riemannian manifold on which the differential geometric structure is imposed by the unified field tensor $^{\ast}g^{\lambda \nu}$ through the SE-connection which is both Einstein and semi-symmetric. In this paper, they proved a necessary and sufficient condition for the unique existence of SE-connection and sufficient condition for the unique existence of SE-connection and presented a beautiful and surveyable tensorial representation of the SE-connection in terms of the tensor $^{\ast}g^{\lambda \nu}$. Recently, Chung and et al.([3],1998) obtained a concise tensorial representation of SE-curvature tensor defined by the SE-connection of $^{\ast}g-SEX_n$ and proved deveral identities involving it. This paper is a direct continuations of [3]. In this paper we derive surveyable tensorial representations of constracted curvature tensors of $^{\ast}g-SEX_n$ and prove several generalized identities involving them. In particular, the first variation of the generalized Bianchi's identity in $^{\ast}g-SEX_n$, proved in theorem (2.10a), has a great deal of useful physical applications.

• International Journal of Concrete Structures and Materials
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• v.9 no.1
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• pp.61-67
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• 2015

The concept of horizontal shear connection utilization on wood-concrete beams intends to be an alternative connection detail for composite wood-concrete decks. The volume of sawn-wood is over three times more expensive than concrete, in Brazil. In order to be competitive in the Brazilian market we need a composite deck with the least amount of wood and a simple and inexpensive connection detail. This research project uses medium to high density tropical hardwoods managed from the Brazilian Amazon region and construction steel rods. The beams studied are composed of a bottom layer of staggered wood boards and a top layer of concrete. The wood members are laterally nailed together to form a wide beam, and horizontal rebar connectors are installed before the concrete layer is applied on top. Two sets of wood-concrete layered beams with horizontal rebar connectors (6 and 8) were tested in third-point loading flexural bending. The initial results reveal medium composite efficiency for the beams tested. An improvement on the previously conceived connection detail (set with six connectors) for the composite wood-concrete structural floor system was achieved by the set with eight connectors. The new layout of the horizontal rebar connectors added higher composite efficiency for the beams tested. Further analysis with advanced rigorous numerical Finite Element Modeling is suggested to optimize the connection parameters. Composite wood-concrete decks can attend a large demand for pedestrian bridges, as well as residential and commercial slabs in the Brazilian Amazon.