• Applied Chemistry for Engineering
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• v.20 no.2
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• pp.117-125
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• 2009

In order to utilize natural gas (NG), one of the clean energy sources in next-generation, as a fuel for vehicles, it is important to store natural gas with high density. To store NG by adsorption (ANG) at room temperature and at relatively low pressure(35~40 atm) is safe and economical compared with compressed NG and liquefied NG. However, so far no adsorbent is reported to have adsorption capacity suitable for commercial applications. Nanoporous materials including metal-organic frameworks can be potential adsorbents for ANG. In this review, physicochemical properties of adsorbents necessary for high adsorption capacity are summarized. Wide surface area, large micropore volume, suitable pore size and high density are necessary for high energy density. Moreover, low adsorption-desorption energy, rapid adsorption-desorption kinetics and high delivery are needed. Recently, various efforts have been reported to utilize nanoporous materials in ANG, and it is expected to develop a nanoporous material suitable for ANG.

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.143-146
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• 2006

좁은 국토와 한정된 자원, 주변 국가와의 외래 관광객 유치 경쟁의 심화 등의 이유로 관광산업의 지속적인 발전이 힘들다는 전망이 대두되고 있다. 따라서 날로 다양해지는 관광소비자의 욕구를 정확하게 분석하고, 국내외 관광시장의 흐름을 파악해야 하며, 이러한 관점에서 분석한 결과, 국내 관광지에는 관광객을 유혹할만한 정보를 얻기 힘들고, 이미 통용되고 있는 관광정보 또한 기본적이고 단순한 정보에 지나지 않음을 알 수 있었다. 이에 본 연구는 이야기가 있는 관광지의 정보를 제공하여 보다 흥미 있는 관광정보를 제공하고, 여행자 개개인의 적극적 참여를 유도하기 위해 콘텐츠에 이야기, 애니메이션 및 게임을 제공하고, 주변상점과의 제휴를 통해 상호작용이 가능한 콘텐츠를 개발하였다. 또한 모바일 기기를 기반으로 하여 칼라코드, SMS등의 이용으로 보다 흥미롭고 사용이 편리한 콘텐츠를 개발하고자 노력하였으며, 캐릭터를 개발하여 과학적인 마케팅 전략의 수립으로 지속적인 제주관광발전을 도모하고자 하였다.

• Journal of Engineering Education Research
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• v.3 no.2
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• pp.3-13
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• 2000

The paper has analyzed and summarized about the theoretical problem occurred in the CAQC, and has developed the learning model focused on the histogram as a case study. The range of study is to systematize the basic method of histogram generally used, and to make step by step procedures under the interactive relation with the improvement of the theory that must be added in case of the calculation by the aided of MS-Excel software. A histogram is the theory to understand the population distribution from which samples are extracted, so alternative methods are presented to estimate the population shape through an experiment and a practice. In order to enlarge the application area of the histogram in the factory, the theory of normal test, the criteria of process capability index and the probability calculation of PPM are added to the histogram. The learning model of CAQC education is proposed that is consistent with the target of histogram to control and search the cause of item defectives fast and correctly.

• Journal of Engineering Education Research
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• v.11 no.4
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• pp.94-108
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• 2008

The purpose of this study falls into the development of national skill system in environmental field. The jobs were classified by the commonly used terms in the field. Consequently there are three large groups, twelve middle groups which again narrow down to smaller jobs according to the relevant characteristics of each job in the group, and forty one jobs in total in the area. Six levels were identified for the definition of job level and the development of performance level by reflecting job levels by expertise. Under the consideration of the unique characteristics of the environment field, job levels were also defined in accordance with each area such as 'environment plan and assessment', 'measurement and analysis of environment', 'environment management', 'environment design and construction', 'environment health management', 'environment resources management', 'environment management and consulting', and 'environment education'. Based on these classification, the definitions of jobs and the standards of performances by jobs and levels were resulted in through a consultation consisting of experts in the environment industry and academy.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.193-194
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• 2014

원전은 고온기능시험 이후 2차계통 내부를 상대습도 40%이하로 관리하여 계통 재질 부식을 최소화하고 있다. 일반적으로 발전소에서는 운전 정지 후 상대습도 40%이하로 낮추는데 15일정도 소요되지만, 발전소 계통 중 일부 곡관부위는 약 60일정도 소요된다. 본 연구는 일부 계통 재료가 상대습도 제한치(<40%) 이상의 환경에서 장기간(최대 60일) 노출시 재료 건전성에 미치는 영향 평가이다. 평가를 위해 시편의 실험 전, 후 무게변화를 이용한 부식률 측정과 표면분석을 위해 광학현미경을 이용하였다. 사용 시편의 재료는 SA516 Gr.70이며 표면상태를 인위적으로 산화피막을 생성 시킨 것(2개)과 산화피막이 없는 것(6개)으로 2종류로 제작하였다. 총 시험기간은 60일이고 시험기간 중 산화피막이 없는 시편은 7일, 21일, 60일에 시편을 2개씩 꺼내어 무게를 측정하여 부식률을 계산하였다. 실험결과, 산화피막이 없는 시편은 노출되는 시간에 따라 부식률이 각각 0.35(7일), 0.21(21일), 0.67(60일) mpy이었고 산화피막이 있는 시편은 0.06(60일) mpy였다. 산화표면 분석결과, 산화피막이 없는 시편은 노출되는 시간에 관계없이 물방울이 맺힌 부분에 pitting을 확인하였다. 하지만, 산화피막이 있는 시편은 pitting의 흔적은 없었다. 산화피막이 없는 시편의 경우 시간에 따라 부식률은 높아지지만 학계에서 통용되는 뛰어난 내부식성 재료의 부식률 기준인 < 1 mpy이하기 때문에 재료 건전성에 미치는 영향은 거의 없을 것으로 판단된다. 또한, 대부분 원전의 경우 고온기능시험 또는 운전기간 동안에 2차계통 구성 재료 표면에 산화막이 생성되었기 때문에 산화피막이 있는 시편의 결과로 판단하면 상대습도 40%이상에 60일 이상 노출되어도 부식은 거의 일어나지 않았을 것으로 사료된다. 실증실험결과를 가지고 종합적으로 평가하면 상대습도 40%이상 환경에서 곡관부위가 60일이상 노출되어도 재료 건전성에 미치는 영향은 거의 없을 것으로 판단된다.

• Geotechnical Engineering
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• v.8 no.4
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• pp.5-16
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• 1992

The main purpose of this the sutdy is to develop the reinforced earth structure design method considering induced stresses and deflections resulting from placement and compaction of soil. In this paper, the new reinforcement Geolog developed by the author is also introduced which is being used as one of the effective earth reinforcing structure against compaction induced stresses. This study adopted the Seed's bilinear model in the estimation of the com paction induced stresses and compute the peak lateral stresses during compaction by doubled Boussinessq's elastic solution of mirror image theory, thereafter, calculate the residual compaction induced lateral stresses from the above peak lateral stress by the residual fraction. It is considered to be reasonable that the compaction induced stresses be added to the lateral earth pressures estimated from conventional gravity analysis considering the actual stresses during service life of the structures. "GEOLOG", a composite of steel bar and attached concrete stopper is found to be effective against tension and pull - out failure. In this paper, the design method considering the compaction induced stresses and the effect of Geolog reinforcement is suggested for the remforced earth structures where backkfill settlement on displacements are not allowed as in the cases of the bridge abutments or double faced reinforcement earth structures.tructures.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.9B
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• pp.923-930
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• 2009

Digital Rights Management(DRM) is a term that refers technologies for imposing limitations on the use of digital content for protecting media copyright holders. This paper proposes a generic scheme for digital media copy protection that can be applied to any digital media such as audio, video, etc. The scheme will make it very hard to play a copied content on a foreign platform and to guess secret content encryption keys. Unlike other DRM techniques, the scheme uses the stream cipher HC-256 only for encrypting media content and it allows a client to start content playback immediately following its streamed decryption. As to the encryption, it requires to generate several secret keys for each new client(player copy), rather than for each media content, which makes it scalable in terms of managed keys. Also, for simplicity, the scheme supports the popular unlimited-play-after-download policy only, which would eliminate the necessity for deploying separate server or process for licensing.

• Fire Science and Engineering
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• v.28 no.2
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• pp.48-53
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• 2014

In this study, we would evaluate fire risk by domestic standard for artificial turf installed on field and roofs. Today domestic regulation for artificial turf only applies to outdoor uses and especially KS M 3888-1 has compulsion but limited to school athletic facilities. Indoor regulation complying with National Emergency Management Agency (No. 2012-35) was enacted as recommendations. Thus this study did combustion test of artificial turf installed on field. Analyzed result by 45 degree flammability test, standard was inadequate to judge the fire risk so we compared and analysed its characteristic through combustion test of flame retardant finishing carpet used as flooring. Test and assessment result of its ignitionability by 45 degree flammability test showed that carpet was satisfied with flame retardant finishing performance standard contrary to artificial turf. For this reason, by conducting cone calorimeter test, the combustion property after ignition would be analyzed and evaluated and then this study will suggest a countermeasure for strengthening standard.

• Journal of Korean Society for Geospatial Information Science
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• v.3 no.2 s.6
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• pp.63-74
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• 1995

The most important thing for the national GIS development is considered to be the standardization, especially the development of the standard coding scheme for the GIS features and attributes. The comparative study on those of the several international transfer standard is, therefore, very meaningful. In this paper we analyzed the features and attributes coding catalogue for the three different exchange standards; SDTS, DIGEST and SP-57. And also the new coding scheme is proposed as the unified standard frame to be used for all the GIS related application and the digital product.

• Journal of Convergence for Information Technology
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• v.10 no.2
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• pp.146-153
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• 2020

This study is a fusion study combining service marketing in the field of Naturopathy and business administration to examine the impact of the quality of Naturopathy services on the loyalty of customers using it, and see if the service value and customer satisfaction are mediated between the two variables. Through these efforts, the government wanted to contribute to the basic provision of research on Naturopathy services and the development of related industries. For the purpose of the study, a range commonly used as Naturopathy was presented to those in their 20s to 50s nationwide, and a survey was conducted on the relevant experience. Data analysis uses the AMOS 24.0 program to identify the causal relationship between the variables and the statistical program SPSS 24.0. The study found that the quality of the Naturopathy service had a positive effect on the loyalty of the customers who used the service, and that the value of the service and customer satisfaction were mediated between the service quality and loyalty, and had a positive effect.