• 한국수소및신에너지학회논문집
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• 제33권6호
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• pp.636-642
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• 2022

The "Hydrogen Economic Activation Road map" was announced in 2019, and hydrogen demand is expected to exceed 470,000 tons per year in 2022 and keep increasing. Under this circumstance, it has become important to understand the greenhouse gas (GHG) emissions associated with various hydrogen production pathways. In this study, the evaluation of life cycle GHG emissions regarding the hydrogen produced as by-product from coke oven gas (COG) in steel mill is conducted. To cover the possible range of operations, three literatures were reviewed and their data of inputs and outputs for the process were adopted for calculation. Life cycle inventories and emission factors were mostly referred to GaBi and Intergovernmental Panel on Climate Change (IPCC) guidelines, respectively. When there are multiple products from a single process, the energy allocation method was applied. Based on these sources and the assumptions, the life cycle emission values of COG-based hydrogen were found to be 3.8 to 4.7 kg/CO₂-eq./kg-H₂.

• 국제지역연구
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• 제21권1호
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• pp.303-324
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• 2017

유엔임무단에 파병되는 한국군의 평화활동 성과를 측정하는 현행평가방식에 대해 적절성, 타당성, 신뢰성문제가 불가피하게 제기되고 있다. 이에 본고는 유엔현장임무단과 국제개발커뮤니티에서 널리 채택한 바 있는 성과기반평가(RBE)모델을 한국군 파병부대의 평화활동에 부합하도록 보완 및 적용하는 방안을 제시하고자 한다. 연구결과, 논리체계모형을 토대로 기획과 평가단계를 통합하는 RBE모델을 토대로 파병 전기획, 파병기간 중 모니터링과 단계적 평가, 파병 후 영향평가의 사이클로 귀결되는 틀을 제안하였다. 둘째, 현행 한국군 평화활동의 모니터링과 평가체계를 RBE모델 기준을 적용하여 검증한 결과, 평가조직 운용 및 논리체계모형에 해당되는 요소들이 기준을 충족하지 못하거나 부분적으로만 충족하였고 파병사후 영향평가는 거의 수행하지 않은 것으로 나타났다. 결론적으로 전술한 문제점들의 해결방안과 민-관-군 분야 전문가가 참여하는 합동조사단 운용을 정책제안으로 제시하였다.

• 비파괴검사학회지
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• 제26권3호
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• pp.153-161
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• 2006

A simulation program SIMULTSONIC is under development at CNDE to help determine and/or help optimize ultrasonic probe locations for inspection of complex components. SIMULTSONIC provides a ray-trace based assessment for immersion and contact modes of inspection. The code written in Visual C++ operating in Microsoft Windows environment provides an interactive user interface. In this paper, a description of the various features of SIMULTSONIC is given followed by examples illustrating the capability of SIMULTSONIC to deal with inspection of canonical objects such as pipes. In particular, the use of SIMULTSONIC in the inspection of very thin-walled pipes (with 450 urn wall thickness) is described. Ray trace based assessment was done using SIMULTSONIC to determine the standoff distance and the angle of oblique incidence for an immersion mode focused transducer. A 3-cycle Hanning window pulse was chosen for simulations. Experiments were carried out to validate the simulations. The A-scans and the associated B-Scan images obtained through simulations show good correlation with experimental results, both with the arrival time of the signal as well as with the signal amplitudes.

• 산업공학
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• 제9권2호
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• pp.191-202
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• 1996

A variety of approaches on performance evaluation modeling have appeared in the technical literature for flexible manufacturing systems(FMS) which can be evaluated only through computer simulation. This study represents a comparative approach for FMS performance evaluation modeling based on reliability, availability and maintainability, and life cycle cost. The methodology proposed in this research includes the following three-step generative approaches. First, a static model to find the initial system configuration is considered under the assumption that the system availability is given as one (failure and maintenance are not considered), and in second step, a stochastic simulation is proposed to serve as a performance evaluation model for FMS with stochastic failure and repair time. In the last step, we developed a simulation modeling using a simulator, FACTOR/AIM to consider a variety of performance factors and dynamic behavior of FMS. Also the applicability and validity of the proposed approaches has been tested and compared through the results of a sample problem using computer programs and procedures developed in each step.

• International Journal of Automotive Technology
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• 제5권2호
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• pp.115-122
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• 2004

Evaluation of active safety control systems usually relies heavily on field testing and is time-consuming and costly. Advances in computer simulations make it possible to perform exhaustive design trials and evaluations before field testing, and promise to dramatically reduce development cost and cycle time. In this paper, a comprehensive simulation-based evaluation procedure is proposed, which combines standard evaluation maneuvers, worst-case techniques, and a driver model for closed-loop path following evaluations. A vehicle dynamic controller (VDC) for a popular Sport Utility Vehicle is evaluated using the proposed procedure. Simulation results show that the proposed procedure can be used to assess the performance of the VDC under various conditions and provides valuable information for the re-design of the VDC.

• 한국산학기술학회논문지
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• 제13권9호
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• pp.3952-3961
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• 2012

세포주기조절유전자를 식별하는 계산방법을 개발하는 것은 시스템 생물학의 중요한 주제중 하나이다. 이전 방법의 대부분은 세포주기 조절 유전자를 식별하는 표현신호의 주기적인 특성으로 간주한다. 그러나, 세포주기 조절유전자는 상대적으로 세포 네트워크를 기반으로 서로 활성화된 상대적으로 많은 상호 작용을 일으킨다고 가정한다. 본 연구에서는 세포주기 분석에 변수 위상동기화 이론을 적용하여, "통계적상 동기화를 이용한 자가조직지도 (SOMPS)", 즉, 자가조직지도와 다변수 통계 동기화 방법으로 이루어진 방법을 사용하여 여러 개의 하위집합과의 상호작용을 발생시키고자 한다. 평가방법으로 SOMPS방법 알고리즘이 세포주기조절 유전자를 방법으로 기존에 사용되는 방법들과 같이 유용할 것으로 보인다.

• 한국초등과학교육학회지:초등과학교육
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• 제33권2호
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• pp.306-321
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• 2014

This study aims to analyze difficulties that pre-service elementary teachers experience in investigating the life cycle of a common cabbage butterfly in person. As difficulties they face during the process of this research, they pointed out collecting eggs, observing molting, creating environments for a breeding cage, feeding, building a breeding cage, and making butterfly specimens. Out of all the environmental difficulties related to their school fields, they pointed out a difficulty of time management most of all, followed by placing a breeding cage in the classroom and the lack of microscopes for observation. In regard to difficulties related to their evaluations on students' activities, they found it difficult to evaluate students' activity with the life cycle of an insect in the aspect of knowledge and even to set evaluation criteria. Besides, many of them responded that it would be appropriate to evaluate a research on the life cycle of an insect through a portfolio or an observation journal. In regard to difficulties in terms of teachers' knowledge, they found it difficult to understand insect molting, metamorphoses, complete metamorphoses, incomplete metamorphoses, the structure of an insect body, and how to distinguish a female insect from a male one. In regard to the application of class models, they knew it is important for students to have various experiences through direct observation, so the experience-based learning model was proper for the process of observing the life cycle of a common cabbage butterfly. However, they found it difficult for students to observe each stage of the life cycle in person.

• Journal of Advanced Marine Engineering and Technology
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• 제40권7호
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• pp.593-598
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• 2016

LNG 선박용 성형 벨로우즈의 성형방법에 따른 특성을 파악하기 위하여 정적시험과 저주기 피로시험을 실시하였다. 벨로우즈의 규정된 수명 사이클인 8,000회를 실시하여 시험전후의 벨로우즈의 각 산에 걸리는 변형률과 응력을 측정하여 성형방법에 따른 벨로우즈간의 차이를 분석하고 산 별 응력분포를 살펴보았다. 본 저주기 피로시험은 x-y방향의 변위가 가능한 유압시스템의 구조시험장비에 성형 벨로우즈를 장착하고 벨로우즈의 각 산에는 스트레인게이지를 장착하고 멀티레코더를 통하여 데이터를 처리하였다. 이를 통하여 벨로우즈가 성형방법에 따른 수명의 차이가 있는지 살펴보았고, 성형방법에 따른 수명의 차이를 주는 원인을 분석하였다.

• 대한인간공학회지
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• 제30권5호
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• pp.589-595
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• 2011

Objective: This study compares two visual occlusion methods for the evaluation of in-vehicle interfaces. Background: Visual occlusion is a visual demand measuring technique which uses periodic vision/occlusion cycle to simulate a driving(or mobile) environment. It has been widely used for the evaluation of in-vehicle interfaces. There are two major implementation methods for this technique: (1) occlusion using PLATO(portable liquid crystal apparatus for tachistoscopic occlusion) goggles; (2) occlusion using a software application on a touchscreen device. Method: An experiment was conducted to examine the visual demand of an in-vehicle interface prototype using the goggle-based and the touchscreen-based occlusion methods. Address input and radio tuning tasks were evaluated in the experiment. Results: The results showed that, for the radio tuning task, there were no significant differences in total shutter open time and resumability ratio between the two occlusionconditions. However, it took longer for the participants to input addresses with the touchscreen-based occlusion. Conclusion & Application: The results suggest that touchscreen-based method could be used as an alternative to traditional, gogglebased visual occlusion especially in less demanding visual tasks such as radio tuning.

• KIEAE Journal
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• 제13권5호
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• pp.79-88
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• 2013

This study creates the evaluation criteria to analyze the $CO_2$ emission quantity in the complex of apartment house among domestic buildings and proposes how to calculate the $CO_2$ emission quantity by the only simple information of apartment house. The study shows that in order to create the index of carbon emission evaluation criteria, $CO_2$ emission quantity for its input materials in these 27 apartment houses are 445,412g-$CO_2/m^2$ for apartment building, 474,322g-$CO_2/m^2$ for the basement parking lot, 483,523g-$CO_2/m^2$ for welfare facility, 729,957g-$CO_2/m^2$ for sales facility, 743,560g-$CO_2/m^2$ for other facility, 26,782g-$CO_2/m^2$ for public facility, 43,659g-$CO_2/m^2$ for landscape, 1,113g-$CO_2/m^2$ for indoor facility, 11,251g-$CO_2/m^2$ for outdoor facility and 891g-$CO_2/m^2$ for common temporary based on the average $CO_2$ emission by facility. We can also see the analysis data that in case of using the selected factors only, the rate of error is 7.51% comparing with the emission quantity by using simplified LCA method this study suggests for the whole range of apartment houses and the rate of error is average 3.24% using selective and main materials. And this it is evaluated that we can get the result which is similar to the actual $CO_2$ emission quantity with only the simple information about the apartment house.