• 한국의류학회지
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• 제44권2호
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• pp.369-383
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• 2020

This study proposes a method to effectively teaching technic for pattern development and virtual garment manufacturing by adopting the K-MOOC platform for the Apparel Pattern CAD curriculum. According to K-MOOC guidelines, Apparel Pattern CAD curriculum were developed and presented through the K-MOOC platform. A questionnaire survey was utilized to evaluate K-MOOC platform features in terms of learner satisfaction when adopting the 5-point Likert scale. Questionnaire survey participants included 52 college students. The result of the survey found that most of the attributes of the K-MOOC platform were highly rated in terms of interaction and learning effectiveness. The user interface of the K-MOOC platform were shown to be satisfactory in terms of usability. Participants gave a positive assessment of the benefits of online lectures when comparing online and offline lectures. In particular, the preference for online lectures in computer-related courses such as CAD was higher than the offline. It was concluded that the Apparel Pattern CAD curriculum based on the K-MOOC platform was effective and satisfactory for learners in various aspects.

• Advances in concrete construction
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• 제9권4호
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• pp.337-343
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• 2020

In the present study, by employing fragility analysis, the seismic vulnerability of a concrete girder bridge, one of the most common existing structural bridge systems, has been performed. To this end, drift demand model as a fundamental ingredient of any probabilistic decision-making analyses is initially developed in terms of the two most common intensity measures, i.e., PGA and Sa (T₁). Developing a probabilistic demand model requires a reliable database that is established in this paper by performing incremental dynamic analysis (IDA) under a set of 20 ground motion records. Next, by employing Bayesian statistical inference drift demand models are developed based on pre-collapse data obtained from IDA. Then, the accuracy and reasonability of the developed models are investigated by plotting diagnosis graphs. This graphical analysis demonstrates probabilistic demand model developed in terms of PGA is more reliable. Afterward, fragility curves according to PGA based-demand model are developed.

• 대한기계학회논문집B
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• 제35권9호
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• pp.897-902
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• 2011

PEMFC 의 내부에서 발생하는 화학반응은 계면의 물리적 조건 및 물성에 지배되고 그 거동은 임피던스로 표현된다. 일반적으로 임피던스 특성은 전기적 등가회로로 표현이 가능하기 때문에 PEMFC의 임피던스 계측 결과를 등가회로를 이용하여 해석함으로써 간단히 성능 진단을 할 수 있을 것이다. 본 연구에서는 이러한 등가회로를 이용하여 고분자 전해질 연료전지의 특성평가에 관한 기초연구를 수행하였다. 교류 임피던스 계측 값과 다양한 등가회로(단순 등가회로, CPE 를 고려한 등가회로, 2 개의 시정수를 고려한 등가회로, 2 개의 CPE 를 고려한 등가회로)를 이용하여 특성평가를 수행하였다. 그 결과 등가회로를 이용한 PEMFC 의 특성평가가 가능하고, 2 개의 CPE 를 고려한 등가회로가 가장 정도가 높음을 확인하였다.

• 한국수자원학회논문집
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• 제37권11호
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• pp.939-947
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• 2004

해안을 통하여 유출되는 지하수량은 하천 유출량에 비하여 상대적으로 크기는 작으나 해안 지역의 지하수자원의 개발과 연안의 오염과 관련하여 중요성을 가진다. 선행 연구에서는 관측정 수위, 투수계수 등의 간단한 자료만을 가지고 지하수의 해안 유출량을 평가하는 방법을 제시하였다 본 연구에서는 남해안과 서해안과 같이 해안선의 형태가 복잡한 경우에 평균동수경사, 해안선의 폭과 담수층의 평균 두께를 산정하는 방법을 제시하여 지하수 해안유출량 평가의 정확도를 높이는 방법을 제안하였다. 제안된 평가 방법은 경계면모델을 이용한 수치해와 비교하여 평가되었다. 해안선의 복잡성을 고려하지 않은 Darcy의 법칙의 적용에 비하여 정확도가 대폭 개선되었다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.735-741
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• 2011

In the early phase of vehicle development, CAE is conducted as tool for vehicle performance assessment. To maintain acceptable road noise performance, solution for reduced vehicle sensitivity is required. Chassis interface dynamic stiffness characteristics are key component to isolating vibration and noise of road from the vehicle interior. This research provide how to set up the optimized dynamic characteristics under noise effect through DFSS study. CAE-based DOE is performed to build prediction math model, CMS process involves DOE to achieve very fast run times while giving results very comparable. Minimized $95^{th}$ percentile of performance distribution is applied to minimize vehicle sensitivity and road noise levels variation during the optimization process. Finally, the results of optimization were reviewed for performance and robustness.

• 농촌계획
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• 제13권4호
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• pp.31-42
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• 2007

This study aims to compare internet portal sites for rural tourism, and to suggest the improved contents for homepage information on mountain villages under the Korea Forest Service. Design, interface, information source, and communication as estimation indicators were used to understand the characteristics of portal sites, and sub-items under indicators to analyse the portal sites were established. Nationwide portal sites were compared for rural tourism information. Also, German and Italian portal sites were compared as overseas cases. As a result, an internet portal site for information on mountain villages under the Korea Forest Service has to be improved as compared with other portal sites related to rural tourism. Firstly, it is necessary to modify and improve the category explaining mountain villages. Secondly, homepage for developing mountain villages has to be established and linked to potential visitors. Thirdly, portal sites for developing mountain villages subsequently have to be constructed under the site of the Korea Forest Service.

• 정보저장시스템학회논문집
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• 제5권2호
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• pp.82-88
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• 2009

Understanding the adhesion behavior and characteristics of toner film is required to achieve image and text printing with high quality resolution. Toner can be considered as a thin film coating on a media such as paper or polymer film. Quantitative measurement of adhesion characteristics of the thin film is important to assess the reliability of the system. In this work the main objective was to investigate the adhesion characteristic between the toner and the media by ramp loading scratch test method. The scratch test may be used to obtain quantitative information about the adhesion of the film to the substrate. In the scratch test a diamond tip was used to scratch the surface of the toner film under an increasing normal load until the toner detached or fractured. The critical load (LC) was obtained from the experimental results. Also, the relationship between the critical load and the adhesive strength of the interface between the substrate and the toner was obtained by measuring the normal and tangential forces during the scratch test. Finally, theoretical analysis of the toner scratch characteristics was performed based on Benjamin and Weaver theory, Plowing model, and Laugier model.

• 한국지반신소재학회논문집
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• 제2권1호
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• pp.3-13
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• 2003

최근 우수한 경제성과 수려한 외관 및 시공의 간편성 등에 의해 토목섬유를 보강재료로 이용한 보강토 구조물의 건설이 나날이 증가하고 있다. 이러한 토목섬유 보강토 구조물의 해석과 설계 시 가장 중요한 인자인 흙/토목섬유 마찰특성의 평가방법이 표준화되어 있지 않고, 기 제안된 해석 및 설계방법들에 큰 차이가 있어 실무설계자들에게 혼란을 주고 있다. 본 연구에서는 최근 보강재로 놀리 사용되고 있는 토목섬유와 국내 화강풍화토의 마찰특성을 인발시험을 통해 보다 합리적을 평가할 수 있는 방법을 제시하기 위해, 인발시험의 주요 영향인자들인 인발속도, 보강재의 종류, 토목섬유 시료의 폭, 수직하중 및 토목섬유의 수동저항 부재의 유 무 등을 고려하여 흙/보강재의 마찰정수를 도출하였다.

• Structural Engineering and Mechanics
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• 제53권6호
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• pp.1183-1200
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• 2015

Reinforcement corrosion can cause serious safety deterioration to aging concrete structures exposed in aggressive environments. This paper presents an approach for reliability analyses of deteriorating reinforced concrete structures affected by reinforcement corrosion on the basis of the representative symptoms identified during the deterioration process. The concrete cracking growth and rebar bond strength evolution due to reinforcement corrosion are chosen as key symptoms for the performance deterioration of concrete structures. The crack width at concrete cover surface largely depends on the corrosion penetration of rebar due to the expansive rust layer at the bond interface generated by reinforcement corrosion. The bond strength of rebar in the concrete correlates well with concrete crack width and decays steadily with crack width growth. The estimates of cracking development and bond strength deterioration are examined by experimental data available from various sources, and then matched with symptom-based lifetime Weibull model. The symptom reliability and remaining useful life are predicted from the predictive lifetime Weibull model for deteriorating concrete structures. Finally, a numerical example is provided to demonstrate the applicability of the proposed approach for forecasting the performance of concrete structures subject to reinforcement corrosion. The results show that the corrosion rate has significant impact on the reliability associated with serviceability and load bearing capacity of reinforced concrete structures during their service life.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2007년도 정기 학술대회 논문집
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• pp.90-95
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• 2007

Conventional bridge inspection involves the physical positioning of an inspector by the hydraulic telescoping boom of a "snooper truck" thereby providing visual access to bridge components. The process is time consuming, hazardous, and may be affected by lighting conditions, Therefore, it is of great interest that an automated and/or teleoperated inspection robot be developed to replace the manual inspection procedure. This paper describes the advanced bridge inspection robot system under development and other related activities currently undergoing at the Bridge Inspection Robot Development Interface (BIRDI). BIRDI is a research consortium with its home in the Department of Civil and Environmental System Engineering at Hanyang University at Ansan. Its primary goal is to develop advanced robot systems for bridge inspection and monitoring for immediate field application and commercialization. The research program includes research areas such as advanced inspection robot and motion control system, sensing technologies for monitoring and assessment, and integrated system for bridge maintenance. The center embraces 12 institutions, which consist of 7 universities, 2 research institutes, and 3 private enterprises. Research projects are cross-disciplinary and include experts from structural engineering, mechanical engineering, electronic and control engineering. This research project will contribute to advancement of infrastructure maintenance technology, enhancement of construction industry competitiveness, and promotion of national capacity for technology innovation.