• Journal of Science Education
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• v.34 no.2
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• pp.327-341
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• 2010

The purpose of this study is to obtain science high school students' perceptions of scientists and their work before and after the Green Investigation program with scientists. This study also attempts to determine whether the program affected the participants' perceptions of scientists and their work. A modified DAST was carried out with 64 high school students. Findings revealed that Korean science high school students had normal perceptions of scientists, such as images of 20 to 30 year old males wearing laboratory coats and working alone in research labs with test tubes, flasks, and several machines in the background. After the intervention, students drew fewer typical items representing scientists and had significantly different perceptions of their work places between the pretest (M=1.69, SD=1.14) and posttest (M=1.96, SD=1.24, t=4.43, p<0.001) with the eta squared statistics (.24). These findings reflect the need for continued efforts of developing green investigation programs with scientists for students. Some future studies based on this study are also introduced.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.05a
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• pp.239-242
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• 2009

최근 3 차원 측정 기술을 활용한 운동 기능성의 향상을 위한 연구가 활발히 진행되고 있다. 그 예로 3 차원 인체 정보를 이용한 의복패턴 제작 시에 필요한 절개선으로 피부상에서 동작 시 늘어나지 않는 선(Lines of Non-Extension, LoNE)을 찾아내어 활용한 연구가 발표된 바 있다. 이러한 LoNE 은 기존 의복구성을 위한 봉제선이나 기능선으로 활용될 때 동작기능성을 저해하지 않는 특징이 있다. 이에 본 연구에서는 스포츠웨어에서 활동성이 큰 상체의 어깨부위에서 Lines of Non-Extension 을 탐색하고자 하였다. 연구 방법으로는 20 대 후반 남성 2 명을 대상으로 체표의 등 부분에서 3cm 간격으로 계측점을 표시한 후 3D 인체 데이터 (Cyberware, WB)를 획득하였다. 측정시의 자세는 팔을 $30^{\circ}$, $90^{\circ}$, $135^{\circ}$, $180^{\circ}$ 외전시켰다. 피부 표면에서의 길이 변화는 구획의 크기를 달리하면서 가로, 세로, 사선방향으로 동작에 따라서 측정하였다. 변화량은 정자세($30^{\circ}$)를 기준으로 A 라 하였을 때, 기준자세와의 차이가 가장 큰 변화량을 보인 자세를 B 라 하고 A 와 B 간의 차이로 계산하였다. 연구결과, NASA 의 Biosuit 에서 소개된 Iberall(1970)의 LoNE 중 진동둘레를 포함한 팔 부위와 등, 어깨 부위에서 유사한 라인을 찾았다. 본 연구에서와 같이 구획별 사선방향 피부 변화량을 측정하는 것은 피부면에 숨겨진 인간공학적 의복 기능선을 탐색하는 데 효과적임을 확인하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.6
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• pp.504-510
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• 2004

The objective of this paper is to propose the image interpolation method with pseudomedian filter for Field warping and morphing, and to evaluate and analyze its subjective image quality. The Field warping relatively gives rise to more computing overhead, but it can use the control line to control the warping result with more elaboration. Due to the working characteristics of the image warping and morphing process, various complex geometrical transformations occur and a image interpolation technique is needed to effectively process them. Of the various interpolation techniques, bilinear interpolation which shows above average performance is the most widely used. However, this technology has its limits in the reconstructivity of diagonal edges. The proposed interpolation method is to efficiently combine the bilinear interpolation and the pseudomedian filter-based interpolation which shows good performance in the reconstructivity of diagonal edges. According to the proposed interpolation method, we could get more natural warping and morphing results than other interpolation methods.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.5
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• pp.59-67
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• 2014

In tension lap splices of straight deformed bars, KCI Code (KCI2012) and ACI Code (ACI318-11) requires that the lap lengths for class B splice are 1.3 times as development length. KCI2012 contains development length provisions for the use of headed deformed bars in tension and does not allow their tension lap splices. The purpose of this experimental study is to evaluate that KCI2012 equation for the development length, $l_{dt}$, of headed bars can be used to calculate the lap length, $l_s$, of headed deformed bars in grade SD400 and SD500, having specified yield strength of 400 and 500 MPa. Test results showed that specimens with $l_s$ equal to $1.3l_{dt}$ had maximum flexural strengths as 1.16~1.31 times as the nominal flexural strengths, flexural failure mode, and ductility. These observations indicate that $1.3l_{dt}$ is suitable to the tensile lap length of headed deformed bars in grade SD400 and SD500.

• Economic and Environmental Geology
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• v.23 no.4
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• pp.453-463
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• 1990

The Yechon shear zone developed by strike-slip movement was formed in a relatively high temperature condition just after the Jurassic syntectonic granites had been emplaced during Daebo Orogeny. Post-emplacement formation of the shear zone is favored by continuity of foliations and lineations within and without the granites, development of mylonitic structures in the wallrocks, deformation of pegmatite and felsite dikes, and pretectonic growth of porphyroblasts in the wallrocks. A variety of shear sense indicators in the shear zone are predominantly observed in the intensely to extremely deformed rocks. They show that bulk non-coaxial detormation has occurred, and that the sense of shear is consistently dextral with S-C fabrics, grain shape fabrics, asymmetric porphyroclast systems, mica fish, asymmetric extension structures and quartz C-axis fabrics.

• Journal of the Society of Disaster Information
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• v.13 no.2
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• pp.249-257
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• 2017

Recently, a cable disconnection accident occurred due to a lightning strike at the Seohae Bridge located in Dangjin-Pyeongtaek City. This is a natural occurrence, but it is a recall that it is very important to review the safety issues due to the disconnection of cable bridges. In other words, the role of cables in cable bridges has a profound effect on the safety of the structure, and it has become necessary to grasp the effect on the entire structural system. The cable bridge is an economic bridge that builds the main tower and supports the bottom plate by cable. The influence of the cable is the main member, which is a big influence on the safety of the whole bridge system. In the cable-stayed bridge, the cables exhibit nonlinear behavior because of the change in sag, due to the dead weight of the cable, which occurs with changing tension in the cable resulting from the movement of the end points of the cable as the bridge is loaded. Modal analysis is conducted using the deformed dead-load tangent stiffness matrix. A new concept was presented by using divided a cable into several elements in order to study the effect of the cable vibration (both in-plane and swinging) on the overall bridge dynamics. The result of this study demonstrates the importance of cable vibration on the overall bridge dynamics.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.7
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• pp.29-36
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• 2004

In this work, the effect of composite couplings on hub loads of a hingeless rotor in forward flight is investigated. The hingeless composite rotor blade is idealized as a laminated thin-walled box-beam. The nonclassical effects such as transverse shear, torsional warping are considered in the structural formulation. The nonlinear differential equations of motion are obtained by applying Hamilton's principle. The blade response and hub loads are calculated using a finite element formulation in space and time. The aerodynamic forces acting on the blade are calculated by quasi-steady strip theory. The theory includes the effects of reversed flow and compressibility. The magnitude of elastic couplings obtained by MSC/NASTRAN is compared with the classical pitch-flap $({\delta}3)$ or $pitch-lag({\alpha}1)$ coupling. It is found that the elastic couplings have a substantial effect on the behavior of $N_b/rev$ hub loads. Nearly 10 to 40% of hub loads is reduced by appropriately tailoring the fiber orientation angles in the laminae of the composite blade.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.4
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• pp.108-113
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• 2018

Researches on strengthening and rehabilitation methods are being widely conducted due to the deterioration of existing concrete structures. Use of externally bonded Carbon Fiber Reinforced Polymers (CFRP) strips for the rehabilitation is a cost-effective and time-saving method. Generally, the CFRP layout for the shear strengthening was a uni-directional layout. Many researches have focused on the variables of the uni-directional CFRP layout such as the amount of material, angle, and spacing. Pilot tests indicated that the effective confinement of the concrete member can be provided with the bi-directional CFRP layout than the uni-directional layout. Therefore, the test was carried out after the uni- and bi-directional strengthening work using the same amount of CFRP material. CFRP anchors were installed to prevent unexpected premature CFRP delamination failure before reaching CFRP fracture strain. The effectiveness of the CFRP anchor and bi-directional CFRP layout for shear strengthening was verified based on the principal tensile strain contours.

• Journal of the Institute of Convergence Signal Processing
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• v.11 no.2
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• pp.151-156
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• 2010

This paper is a study on image noise reduction of modified sigma filter by image decomposition using directivity. Conventional sigma filter has been shown to be a good solution both in terms of filtering accuracy and computational complexity. However, the sigma filter does not preserve well small edges especially for high level of additive noise. In this paper, we propose here a new method using a modified sigma filter. In our proposed method the input image is first decomposed in two components that have features of horizontal, vertical and diagonal direction. Then, two components are applied HPF and LPF. By applying a conventional sigma filter separately on each of them, the output image is reconstructed from the filtered components. Added noise is removed and our proposed method preserves the edges from the image. Comparative results from experiments show that the proposed algorithm achieves higher gains, on average, 2.6 dB PSNR than the sigma filter and 0.5 dB PSNR than the modified sigma filter. When relatively high levels of noise added, the proposed algorithm shows better performance than two conventional filters.

• Journal of Korea Society of Industrial Information Systems
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• v.18 no.2
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• pp.19-25
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• 2013

In this paper, we propose an approach to tracking road regions from video sequences. The proposed method segments and tracks road regions by utilizing the prior information from the result of the previous frame. For the efficiency of the system, we have a simple assumption that the road region is usually shown in the lower part of input images so that lower 60% of input images is set to the region of interest(ROI). After initial segmentation using flood-fill algorithm, we merge neighboring regions based on color similarity measure. The previous segmentation result, in which seed points for the successive frame are extracted, is used as prior information to segment the current frame. The similarity between the road region of the previous frame and that of the current frame is measured by the modified Jaccard coefficient. According to the similarity we refine and track the detected road regions. The experimental results reveal that the proposed method is effective to segment and track road regions in noisy and non-noisy environments.