• Journal of the Earthquake Engineering Society of Korea
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• v.14 no.5
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• pp.41-51
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• 2010

For safe seismic evaluation and design, it is necessary to predict the plastic deformation demands of members. In the present study, a quick and reasonable method for the evaluation of member plastic deformations of dual systems was developed on the basis of results of elastic analysis, without using nonlinear analysis. Plastic deformations of beams, columns, and walls are functions of member stiffness, story drift ratio, and moment redistribution determined from elastic analysis. For dual systems with rigid connections between walls and beams, an increase in the plastic deformations of beams due to the rocking effect was considered. The proposed method was applied to 8-story dual systems and the predicted plastic deformations were compared with the results of nonlinear analysis. The results showed that the proposed method accurately predicted the member plastic deformations with simple calculations, but that for the accurate evaluation of member plastic deformations, the inelastic story drift ratio must also be predicted with accuracy. The proposed method can be applied to both the performance-based seismic design of new structures and the seismic evaluation of existing structures.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11A
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• pp.918-923
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• 2009

In this paper, a design method of the compact narrow band filter on the microstrip board is proposed using complementary split-ring resonators(CSRRs). The design technique of this filter is based on cascading filter stages consisting of the combination of circular CSRRs, capacitive gaps between patches, and inductive grounded stubs with the meander configuration. By these means, it was possible to get the nearly symmetric frequency responses, adjustable bandwidths, compact sizes. And also excellent characteristic of the out-of-band rejection is achieved in contrast to the conventional filter design technique. The measured insertion shows good results about -4.0dB at the center frequency($f_0=1GHz$) and passband return loss is less than -9.4dB. The 3dB fractional bandwidth(FBW) is approximately 4%. The results of the frequency response measured on the fabricated band pass filter substrate show satisfactory agreement with the simulated frequency responses by the HFSS in the region of interest.

• The Mathematical Education
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• v.58 no.2
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• pp.299-317
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• 2019

In this study, we analyzed the change of teacher knowledge through task design in the teacher-researcher community focused on knowledge of students in the area of derivatives application. The following subjects were studied. First, we have analyzed the focus of the discussion related to teacher knowledge of students within the teacher-researcher community. Second, we have analyzed the change of teacher knowledge of students according to the focus. The results of this study are as follows. First, community member' different knowledge of students led the discussion on the task solving paths. The main focus of the discussion was the possibility in inducing responses and motivation. Second, the process of reviewing and evaluating task solving paths and reaching consensus led the improvement of teacher knowledge. Teachers and researchers led changes of teacher knowledge by sharing the knowledge based on previous research and experience, respectively. This ultimately shows the necessity of co-learning between teachers and researchers in teacher education.

• The Journal of Korean Academy of Sensory Integration
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• v.19 no.3
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• pp.44-60
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• 2021

Objective : The purpose of this study was to identify the characteristics of domestic single-subject research related to the participation of students with intellectual disabilities in classes. Methods : We investigated a total of five papers to determine the features and qualitative levels of the papers being analyzed. Results : A total of 12 subjects were studied, and experiments were conducted at all stages. All research used a multiple baseline design. The independent variables were the positive behavior support approach (2), the strength-oriented activities approach, the self-decision teaching and learning model approach, and the self-monitoring approach. As a dependent variables, there were four pieces set up exclusively for class participation behavior, and one that was set up mixed with class interruptions behaviors. The qualitative level of the studies to be analyzed was 100% of the high level. Conclusion : Through this study, single-subject studies that applied interventions related to participation in class for intellectual disabilities in elementary schools have confirmed that effective interventions were applied and that the quality levels were reliable.

• Journal of the Korea Concrete Institute
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• v.22 no.4
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• pp.519-525
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• 2010

Data from beam-based bond tests for FRP bars in the literature were collected and regression analyses were conducted for the data of splitting failure. Average bond strengths obtained from splice tests were found to be lower and more affected by C/$d_b$ values than average bond strengths from anchorage tests, indicating needs of new design equation for the splice length of FRP bars based on the data of splice tests only. In addition, the variation of bond strengths was greater than that of tensile strengths of FRP bars and, therefore, a new safety factor should be involved for the design equation. Five percent fractile coefficients were used to develop the design equations based on the assumption that load and resistance factors for FRP reinforced concrete structures are same to the factors for steel reinforced concrete structures. The proposed design equations give economical and reliable lengths for development and splice of FRP bars. The proposed equation for splice provides shorter lengths than the ACI 440 equation in case of C/$d_b$ of 3.0 or greater. Because FRP bars are expected to be used in slabs and walls exposed to weather with thick cover and large spacing between bars, the proposed equation gives optimal splice lengths.

• Journal of Korean Society of Steel Construction
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• v.26 no.1
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• pp.43-53
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• 2014

A single plate connection(SPC) consists of a plate welded to the columns and bolts connected to the beam web. The SPC is widely used for a simple shear connection of steel structure because it is easy-to-fabricated, easy-to-installed and economical. The conventional SPC is used for 2 to 12 bolts in a single vertical row. It is designed to limit the plate thickness by bolt diameter to obtain flexible and ductile connections. The design strength for eccentric shear shall be the lesser of the shear strength of bolts or bearing strength of plate and when the design strength is decided by edge distance failure, the results can be very conservative. Although the research on special solution for 'weak-plate/strong-bolt' model with 2 to 4 bolts has been conducted by L. S. Muir, and W. A. Thonton, 2004, study on generalized design procedures did not conduct. This study proposed design procedure for evaluation of the design strength of eccentric shear bolt groups on a single plate connection based on the actual edge distance and the direction of bolt reaction forces by using elastic vector method(EVM) and instantaneous center of rotation method(ICM).

• Korean Journal of Heritage: History & Science
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• v.53 no.3
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• pp.80-109
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• 2020

The Sacheonwangsa Temple in Silla is an esoteric temple that was founded provisionally in 670, and was completed in 679. This study attempted to elucidate the planning method of the Sacheonwangsa Temple based on the results of research on excavations and investigations into its construction processes and construction measures thereof. The research results are as follows. (1) In the site construction, assuming the size of one Bang (坊) on the south of Nangsan Mountain, after dividing the north-south width into three equal parts, there is a possibility that two of these parts were set to the flat portion. (2) In the 'Jochang (祖創, 670)', it is estimated that an area of 300 cheoks by 300 cheoks was postulated on the flat surface, and, as an initial conception, the mandala's plane design of the outer square 2 hasta (3 cheoks) and inner square 1 hasta (1.5 cheoks) was originally devised for the setting of 'Mudra (神印)', and an area 100 times greater has been set as the basis in the scale and layout planning of the central block. (3) During 'Gaechang (攺刱, ~679)', it is judged that because of the narrowness of the distance between the Pagoda and Geumdang Hall, which occurs when the center of the Geumdang Hall coincides with the center of 'the first stage of the foundation (先築基壇)', the scale and layout planning were adjusted from the initial conception. (4) The arrangement of the building was determined by dividing the fixed size of the central block (280 cheoks by 320 cheoks). Specifically, the east-west direction is set on the quartile's line of the east-west width of the central block, and in contrast, the north-south direction is based on the structural characteristics of the central block. It is presumed that the position of the transept was determined through the division and adjustment of the column spacing of the east-west corridor, then the Geumdang Hall and Altar were based on this. (5) The scale of the Geumdang Hall and Pagoda is determined by the petition of the division by the unit fraction starting from the quartile's line of the central block's east-west width. This planning is understood to be based on the self-similarity, which is rooted in the mandala's plane design as the model.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.11a
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• pp.253-260
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• 2004

In these days, 8000TEU container ship service launches in shipping service at latest based on the economy of scale, unit cast related with ship operation on ocean decreases in proportion to increase of ship scale and mega ship over 10,000TEU is on planning. This paper is analyzed the economic efficiency for reduction qf calling port in the operation cost, port chnrge, feeder cost, etc by an empirical analysis.

• Magazine of the Korea Concrete Institute
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• v.3 no.1
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• pp.79-85
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• 1991

This paper aims at experimentally investigating the relationship between tensile load and average strain in the tension zone of SFRC beam. Also, it is attempted to find post cracking tension behavior of SFRC under tensile loading condition. The tension stiffening test is conducted on the long prizm of SFRC which embeds reinforcing bar in both ends of member. From this study, an empirical equation which represents the tension stiffening effect(i.e.effect of increasing tensile-~3trengthening contnbuted by SFRC when the reinforcing bar embeded in the SFRC member is under tensile loading condition) as a function of the average strain is presented .

• The monthly packaging world
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• s.260
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• pp.45-55
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• 2014

최근 환경오염과 생태학적 환경문제가 사회적 중요한 관심사로 인식되고 있다. 포장디자인에 있어서도 재활용과 재사용에 대한 요구와 함께 스티로폼이나 플라스틱을 대체하는 친환경 포장용기와 생분해성 필름 등의 포장재의 개발과 생산이 점차 증가하고 있다. 이러한 사회적 배경에서 본 연구에서는 환경친화적 포장디자인의 개발을 위한 가이드라인 설정을 목적으로 하고 있다. 연구내용은 환경친화적 디자인의 개념과 에코 포장디자인 적용범주, 국내외 에코패키지의 동향 및 포장재 현황을 살펴보고, 각종 정책과 규정 및 관련지침 등의 이론적 자료들을 근거로 일반적으로 고려되고 있는 에코패키지의 기본 방향과 체크리스트를 분석하였으며 이에 따른 가이드 라인 및 수행 절차를 고찰하였다. 에코 패키지의 기본방향은 첫째, 포장디자인의 제작, 사용, 폐기에 이르는 전과정에서 환경측면을 고려해야 하며 둘째, 비용과 품질, 시장성, 디자인 등 다중요소를 고려해야 한다. 셋째, 디자인 부서와 제품설계부서, 생산부서, 환경팀 등 조직 내의 다른 시스템과 기능적으로 협력하여야 하며 넷째, 기업의 다른 여러 가지 환경 활동을 통해 잠재적인 소비자와 시장을 확대할 수 있다는 것이다. 가이드라인의 내용은 자원 절감과 물질 사용량 절감, 재활용성 확대, 에너지 효율 향상, 유해 물질 저감과 안전성 확보, 폐기 효율성을 중심으로 하고 있다. 환경 친화적 포장디자인의 실천을 통해 환경영향성을 개선하고 비용을 감소시키며 소비자의 이미지 개선에도 기여할 것으로 기대된다.