• 한국안전학회지
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• 제27권2호
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• pp.49-56
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• 2012

If cement can be manufactured with industrial byproducts such as granulated blast furnace slag, phosphogypsum, and waste lime instead of clinker, there would be many advantages, including maximum use of these industrial byproducts for high value-added resources, conservation of natural resources and energy by omitting the use of clinker, minimized environmental pollution problems caused by CO2 discharge, and reduction of the production cost. By this reason, in this study, mechanical behavior tests of non-burnt cement concrete were performed, and elasticity modulus and stress-strain relationship of non-burnt cement concrete were proposed. 6 test members were manufactured and tested according to reinforcement ratio and concrete compressive strength. By the test results, there was no difference between ordinary concrete and non-burnt cement concrete of flexural behavior. In order to verify the proposed non-burnt cement concrete model, nonlinear analytical model was derived by using strain compatibility method. By the results of comparison between test results, ordinary concrete model and proposed model, The proposed model well predicted the flexural behavior of non-burnt cement concrete.

• 기술혁신학회지
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• 제19권3호
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• pp.439-464
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• 2016

우리나라의 ICT 기기의 기술기준 및 적합성평가절차는 주요 교역 상대국가의 요청, MRA 2단계 체결, 적합성평가서비스시장 확대의 필요성 및 제조업체의 요구에 따라 혁신해야 할 시점이다. 주요 선진국은 이미 민간화 방안을 활용하여 혁신을 진행하고 있었으며, 그 수준을 비교 분석한 결과, 일본이 가장 높은 수준으로 민간화되어 있었고 한국이 가장 낮은 수준으로 나타났다. 국내 민간기관의 시험 인증 능력을 조사한 결과, 우리나라는 현재보다 높은 수준의 민간화가 가능함이 나타났다. 아울러 설문 응답자는 '인증업무의 민간위탁', 'EMC의 민간임의표준으로 전환' 그리고 '적합성평가주체의 전환'에 대하여 긍정적으로 답변하였다. 나아가, '정책 수용성과 갈등 수준'의 관점에서는 '인증업무의 민간위탁'부터 시작하는 것이 바람직해 보이며, 민간화 이전에 인증심사원제도 마련 등 관련 제도를 사전에 개선해야 한다.

• 인터넷정보학회논문지
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• 제13권1호
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• pp.83-98
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• 2012

최근 웹 서비스 기반 서비스 지향 구조가 분산된 애플리케이션의 효율적인 통합을 위한 방법으로 널리 활용되고 있다. 서비스 지향 구조에서의 코레어그래피는 기업 간 비즈니스 프로세스 환경에서 메시지 교환에 초점을 맞춘 협업 방식으로 참여하는 서비스들 사이의 작업 진행 순서와 메시지 교환 프로토콜을 정의함으로써 거시적인 측면에서 전체 프로세스를 모델링하기 위해 사용된다. 그러나 이러한 코레어그래피는 웹 서비스 조합을 실행시키는 방법이 아니기 때문에 구현 모델로 변환 후 사용된다. 따라서 코레어그래피 모델을 실행시키기 위한 구현 모델은 기능적인 측면에서 코레어그래피 모델을 정확하게 구현하였는지 반드시 평가되어야 한다. 이에 본 논문에서는 코레어그래피 모델과 구현 모델의 서비스 조합 적합성을 평가하는 방법과 수행을 통한 동작의 일치성을 보장하기 위한 테스트 방법을 제시한다.

• 한국포장학회지
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• 제22권2호
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• pp.33-37
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• 2016

주로 커피포장에 사용되던 포장용 One-way 가스배출밸브(아로마 밸브)가 최근 발효건강기능식품이나 전자렌지 조리용 즉석식품 포장 등 다양한 영역으로 적용이 확대되고 있다. 포장 식품의 효과적인 신선도 유지와 보존성 향상을 위해서는 대상 식품에 따른 최적의 가스배출 압력을 유지하는 것이 중요하며, 이를 위해 다양한 개방압력(Open Pressure)을 가진 밸브를 개발할 필요가 있다. 본 연구에서는 국내에서 개발된 링타입 고무막을 이용한 식품 포장용 가스배출 밸브(Degassing Valve)에 대하여 오일의 표면장력, 고무막의 재질특성 및 구조 역학적 특성을 분석하여 개방압력 예측이 가능하도록 수학적 분석 모델을 개발하였다. 직관적으로 보면 오일의 점도가 밸브의 개방압력에 영향을 미칠 것으로 예상되지만, 이론상으로 점도는 유체 내부의 요인에 의한 특성이고, 표면장력은 서로 다른 상태의 계면에서 발생되는 특성이므로 점도와 표면장력은 서로 무관하다. 이에 대해 본 연구의 실험을 통해 오일의 점도가 표면장력과는 무관하고 결과적으로 밸브의 개방압력과도 무관함을 확인할 수 있었으며, 수학적 모델에 의한 이론값이 재료의 실험값과 유사한 경향의 결과를 확인함으로써 제안한 수학적 모델의 유효성을 확인할 수 있었다. 따라서, 이 모델을 통해 포장용 가스 배출 밸브의 압력 설계 및 품질 신뢰성 확보를 위한 유용한 자료로 활용될 수 있을 것으로 기대된다.

• 설비공학논문집
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• 제30권2호
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• pp.68-82
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• 2018

Radiant floor heating systems with capillary tubes are energy saving systems in which hot water is circulated into capillary tube with a small diameter. In this study, the heating performance of capillary tube system is investigated in an experimental study and a simulation model. The results of the study showed that, the capillary tube radiant floor heating system maintains a more stable floor surface temperature in comparison a PB pipe system. In terms of energy consumption, the capillary tube radiant floor heating system proved to be more efficient than the PB pipe heating system at $40^{\circ}C$ of low temperature hot water supply. The difference between water temperature and room temperature can be held low for heating which saves energy. Low temperature radiant floor heating system with capillary tubes have significant advantages such as health improvement, low energy cost, optimum use of heat source(boiler) and higher operational efficiency.

• 한국환경과학회지
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• 제29권12호
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• pp.1153-1170
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• 2020

With global warming and the rapid increase in urbanization accompanied by a concentration of population, the urban heat island effects (UHI) have become an important environmental issue. In this study, rooftop greening and permeable asphalt pavement were selected as measures to reduce urban heat island and applied to a simple virtual urban environment to simulate temperature change using ENVI-met. A total of five measures were tested by dividing the partial and whole area application of each measure. The results showed that the temperature range of the base experiment is 33.11-37.11 ℃, with the UTCI comfort level described as strong heat and very strong heat stress. A case applied permeable asphalt has a greater temperature difference than a rooftop greening case, the larger the area where each condition was applied, the greater the temperature change was.

• 한국포장학회지
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• 제30권2호
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• pp.149-160
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• 2024

One of the main functions of packaging is promoting the products. Competitive markets demand that products appeal more to consumers in many perspectives. Other than its original purpose, which is protection, packaging has been tasked with implementing the emotional appeal of a product through unique shapes, textures, and visual designs. Understanding emotional appeals to consumer is a potential marketing strategy so that research have been done about techniques to visualize the design and print the specific textures. Especially, paper-like films are known as eco-friendly or emotional design and they are able to protect the products from oxygen or water vapor better than papers. In this study, paper-like films, which is printed with inks to have rougher surfaces, are analysed in terms of roughness, friction, imaging and sensory evaluation of subjective softness from consumers. Also, the prediction model was established with the correlation of the measured results and sensory panel test (SPT) of consumer preferences by touch. The results showed that the prediction of subjective texture preference was contributed by 63.9% for surface roughness and 36.1% for friction profile parameters. It confirmed that surface roughness characteristics should be prioritized to improve tactile preference for paper-like films.

• 한국분무공학회지
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• 제9권3호
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• pp.42-49
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• 2004

The present article investigates the influence of droplet drag models on predictions of diesel spray behaviors under ultra-high injection pressure conditions. To consider drop deformation and shock disturbance, this study introduces a new hybrid model in predicting drag coefficient from the literature findings. Numerical simulations are first conducted on transient behaviors of single droplet to compare the hybrid model with earlier conventional model. Moreover, using two different models, extensive numerical calculations are made for diesel sprays under ultra-high pressure sprays. It is found that the droplet drag models play an important role in determining the transient behaviors of sprays such as spray tip velocity and penetration lengths. Numerical results indicate that this new hybrid model yields the much better conformity with measurements especially under the ultra-high injection pressure conditions.

• 품질경영학회지
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• 제31권2호
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• pp.17-39
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• 2003

The 21st century is called “an era of creation” or “an era of speed.” These are flat expressions requiring a fierce competition between individuals, corporations and nations. In a reality in which we should make new things continuously within a short period of time, the world best benchmarking can become a good alternative. The world best practice can be called “a mode of operation” that has created the world's best performance in a particular field of managerial activities. It is very meaningful for the nations' corporations, which have a lower competitiveness than world-class ones and weak points in the area of human resources development, in particular, to benchmark the world-class corporations' best practices of HRD. Therefore, this study is conducted in conformity with a model of the Instructional Systems Designs for the Total Quality Education that brings the structure of the world-class corporations' best practices of HRD into line with that of the Total Quality Management. That is, analysis, design, development, implementation and assessment are included in this study.

• 조명전기설비학회논문지
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• 제28권3호
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• pp.63-71
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• 2014

A single-inverted-pendulum model is presented to simulate and predict the passive response of human balance control. This simplified biomechanical model was comprised of a torsional spring and damper, and a lump mass. An estimation of frequency response function was conducted to parameterize the complexity. The frequency domain identification method is used to identify the parameters of the model. The equivalent viscoelastic parameters of standing body were obtained and there was good conformity between the simulation and experimental result.