• Magazine of the Korean Society of Hazard Mitigation
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• v.11 no.2
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• pp.90-95
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• 2011

본 연구에서는 자연사면을 대상으로 적용되는 급경사지 대응공법을 체계적으로 분류하였다. 급경사지재해 대응공법을 합리적으로 조사하기 위하여, 자연사면에 설치된 급경사지 대응공법의 특징을 기록할 수 있는 현장조사 양식을 개발하였다. 자연사면에서 급경사지재해 대응공법은 사면부 적용공법과 계곡부 적용공법으로 분류한다. 따라서 개발된 조사양식도 사면부과 계곡부로 구분하여 작성하도록 하였다. 무주 및 장수지역에 설치된 50개소의 급경사지재해 대응공법에 대한 현장조사결과 사면부의 경우 비탈다듬기와 표면보호를 위한 선떼붙이기, 비탈덮기 등이 주로 보강되어 있다. 계곡부의 경우 대부분 콘크리트 사방댐과 기슭막이가 시공되어 있으며, 슬랫댐과 콘크리트 사방댐 및 기슭막이가 복합적으로 적용되고 있음을 알 수 있다.

• Journal of the Korean School Mathematics Society
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• v.16 no.2
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• pp.289-318
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• 2013

This study was conducted to provide practical ways to apply observation assessments in classrooms. Observation assessments have been asserted to assess elements of mathematical processes which cannot be effectively assessed in traditional paper-and-pencil tests. In order to propose the ways for teachers to actively use observation assessment of mathematics assessments, relevant instruments were developed by analyzing a number of related theories. The observation assessments were applied in classroom settings and the results of this application were analyzed. The findings from this study are expected to suggest beneficial implications for teachers who are interested in practicing observation assessments in classrooms.

• Journal of The Korean Association of Information Education
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• v.21 no.3
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• pp.267-275
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• 2017

The purpose of this study is to analyze the teachers' perceptions about the various evaluation methods used in SW education and to find ways to improve the usefulness of the field. To do this, we surveyed the teachers who were educated about SW education evaluation. As a result of the study, it was recognized that the use of output, portfolio, and observation evaluation in SW education class is suitable for evaluating Computational Thinking(CT) and useful for field application. On the other hand, paper and self-evaluation are useful for field application, but they are relatively inadequate to evaluate CT. Portfolio, design, and interview evaluations are good for measuring CT, but they are difficult to apply to the field. Also, evaluation criteria, evaluation factors, and strategies were found to be difficult to apply. Therefore, we suggest the necessary measures to apply SW education evaluation method more effectively.

• Journal of the Korea Institute of Building Construction
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• v.23 no.5
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• pp.595-605
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• 2023

With the escalating prevalence of modular construction projects, there is a concurrent surge in scholarly and industrial intrigue in this domain, leading to a broadened spectrum of its applications. Modular construction, inherently facilitated by controlled factory settings, boasts the capability to consistently deliver edifices of superior quality. To optimize this advantage, the judicious integration of quality assurance methodologies during the site-specific phases of lifting and assembly is non-negotiable. This research embarked on a survey directed at project stakeholders, aiming to gauge the perceived significance and efficaciousness of prevailing quality preservation and oversight protocols during the aforementioned site stages, subsequently employing the Importance-Performance Analysis(IPA) for data interpretation. The findings elucidated that, while a majority of quality assurance procedures were adeptly executed, perceptual disparities existed among stakeholders regarding certain aspects, prompting recommendations for enhancement. This investigative endeavor lays a foundation, aiding future studies in amplifying the quality assurance cognizance among professionals during modular construction's site-assembly phase.

• Journal of the Korean GEO-environmental Society
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• v.13 no.8
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• pp.5-13
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• 2012

This research have investigated the application and the injection effect of the alkaline silicasol grouting materia (which is) recently developed. To compare the engineering characteristics of the alkaline silicasol which is formed with 3D-gel and the sodium silicate, it have studied the strength and environmental effects through the laboratory test, and field application was investigated with a review of the injection effect and waterproof through the field test. As a result of the laboratory test, unconfined compression strength of alkaline silicasol was 5 times more than sodium silicate. As a result of the leaching test, a total amount of the eluviated elements was very small, it considered the environment-friendly material. As a result of the field test, considerable reduction of the coefficient of permeability at the hydraulic layer was confirmed, and it could secure that the coefficient of permeability showed a lower than standard value of $10^{-5}cm/sec$.

• Tunnel and Underground Space
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• v.18 no.3
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• pp.202-213
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• 2008

In this study, theoretical approach of 3D seismic traveltime tomography was investigated. To guarantee the successful field application of 3D tomography, appropriate control of problem associated with blind zone is pre-requisite. To overcome the velocity distortion of the reconstructed tomogram due to insufficient source-receiver array coverage, the algorithm of 3D seismic traveltime tomography based on the Fresnel volume was developed as a technique of ray-path broadening. For the successful reconstruction of velocity cube, 3D traveltime algorithm was explored and employed on the basis of 2nd order Fast Marching Method(FMM), resulting in improvement of precision and accuracy. To prove the validity and field application of this algorithm, two numerical experiments were performed for globular and layered models. The algorithm was also found to be successfully applicable to field data.

• Journal of the Society of Disaster Information
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• v.20 no.1
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• pp.20-31
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• 2024

Purpose: Research and development of high-strength concrete enables high-rise buildings and reduces the self-weight of the structure by reducing the cross-section, thereby reducing the thickness of beams and slabs to build more floors. A large effective space can be secured and the amount of reinforcement and concrete used to designate the base surface can be reduced. Method: In terms of field construction and quality, the effect of reducing the occurrence of drying shrinkage can be confirmed by studying the combination of low water bonding ratio and minimizing bleeding on the concrete surface. Result: The ease of site construction was confirmed due to the high self-charging property due to the increased fluidity by using high-performance water reducing agents, and the advantage of shortening the time to remove the formwork by expressing the early strength of concrete was confirmed. These experimental results show that the field application of ultra-high-strength concrete with a design standard strength of 100 MPa or higher can be expanded in high-rise buildings. Through this study, we experimented and evaluated whether ultra-high-strength concrete with a strength of 130 MPa or higher, considering the applicability of high-rise buildings with more than 120 floors in Korea, could be applied in the field. Conclusion: This study found the optimal mixing ratio studied by various methods of indoor basic experiments to confirm the applicability of ultra-high strength, produced 130MPa ultra-high strength concrete at a ready-mixed concrete factory similar to the real size, and tested the applicability of concrete to the fluidity and strength expression and hydration heat.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.83-83
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• 2011

나노섬유는 마이크로 섬유에 비해 $10^3$배 정도의 넓은 표면적을 가지며, 다른 섬유와 비교하여 유연성, 투습성과 같은 특성이 우수하다. 나노섬유의 제조방법은 여러 가지가 있으나, 상용화의 가능성, 적용 고분자의 다양성, 제조공정의 단순성, 다양한 제품기술에의 응용성 등을 고려하여 선택하여야 한다. 나노섬유의 제조기술은 방법에 따라 전기방사, 복합방사, 멜트블로운 공정, 에어레이드 공정, 습식 공정 등으로 나눌 수 있다. 전기방사 등 나노섬유를 대량생산하여 상용화하려는 노력을 지속적으로 하고 있으나 나노섬유의 염색가공에 관련되어 기술적 한계로 제품전개에 많은 어려움을 겪고 있다. 그리하여 본 연구에서는 나노섬유 단독으로 제품화하기에는 강도 등의 문제로 PET에 워터펀칭한 복합소재로 개발하여 900nm 이하의 나노섬유에 대한 최적의 날염조건과 현장적용 생산기술을 개발하고자 하였다. 나노섬유 복합소재에 대하여 Brown, Red, Blue, Black 색상의 안료와 Urethane, Rubber, Acrylic, Eco Binder를 사용하여 날염 실험하였으며, 최적의 조건으로 현장생산에 적용하여 생산하였다. 안료의 고착성을 높여 날염성과 염색견뢰도를 증진시키기 위하여 원적외선 열처리기를 개발하여 현장생산에 접목시켰다. 원적외선 열처리기는 벙커C유 또는 가스 등을 사용하는 텐터나 증열기와는 다르게 전기를 에너지원으로 하여 원적외선 램프를 이용한 건열시스템의 형태로 저공해 및 그린 형태의 열처리기 시스템으로, 섬유에 대한 원적외선의 조사거리, 원적외선 램프의 간격, 적용 온도, 원단이송 속도 등에 따른 최적의 원적외선 열처리기 날염조건을 설정하였다. 바인더에 따른 날염성은 우레탄계 바인더를 사용하였을 경우에 가장 선명하고 깊은 색상을 보였으며, 아크릴계 바인더의 경우가 가장 낮은 색상을 보였으며 염색견뢰도는 대체적으로 양호한 결과를 얻었다. 그리고, 최근 환경적인 추세에 맞추어 에코 바인더를 사용하여 날염한 결과 염색성과 내구성 등은 우레탄계와 아크릴계 바인더의 중간 정도의 결과를 보였다.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.223-224
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• 2009

This study was performed to development 80MPa high strength concrete using local raw material of Busan and to estimate field application ability. As the result of three types of mixture, fresh and hardened properties were satisfied with target requirement properties. Hydration temperature was revealed mean 75$\sim$85$\circ$C. Additionally, in case of compressive strength, core specimen's strength is six times higher than field curing specimen by very high hydration heat.

• Tunnel and Underground Space
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• v.25 no.1
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• pp.68-75
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• 2015

Rock mass includes such discontinuities as fault, joint, bedding, crack, schistosity, cleavage. The rock mass behavior, therefore, is influenced by the discontinuity behavior. In this study, a stability and deformation analysis method considering discontinuities in rock mass is proposed, and then applied to the rock collapse disaster site. As the method, the stability analysis by the stereographic projection method was carried out in an actual site, the deformation analysis program by the finite element method including the joint element was developed, and performed. To demonstrate the applicability of this developed stability and deformation analysis method considering discontinuities in rock mass, the analysis results are examined and compared with the failure behavior at the rock mass.