• Journal of the Korean Professional Engineers Association
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• v.16 no.1
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• pp.4-12
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• 1983

Data communication has historically evolved from leased lines, to use of the public telephone network, and eventually to dedicated(exclusive) data networks. It requires an enormous amount of money for establishing a separate and independent data network at the beginning stage. No country has ever adopted this method In the Republic of Korea too the age of leased circuits is passing and it is scheduled to open the public telephone network to the data transmission and to install packet mode processor in the last half of 1983. This paper presents a survey on characteristics of the public telephone network in Seoul and a future development of the data communication of Korea.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.146.1-146
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• 2003

연근의 박피에 따른 감모율은 10%를 넘지 않는 낮은 수준으로 우엉과 마찬가지로 brushing에 의한 박피가 가장 효과적이어서 감모율이 5.1% 수준으로 가장 낮게 나타났다. 박피 처리후의 수분함량 변화도 근채류 전용박피기가 89.24∼87.27% 수준으로 차이가 가장 적게 나타났으며 박피 처리후의 갈변도도 0.02∼0.09 수준이었다. pH 변화도 근채류 전용 박피기에서 6.0∼6.5 수준이었으나 그 밖의 처리구에서는 거의 변화가 없었다. 한편, 마에 있어 박피 감모율은 우엉 및 연근과 비슷한 경향을 보여 brushing 처리에 있어 3.28% 수준, 근채류 전용박피기에서도 5.23%로 낮은 감모율을 나타내었다. 또한, 수작업에 의한 박피 시료는 brushing과 근채류 전용 박피기로 처리한 시료와 비교하여도 처리후의 수분함량 변화, 갈변정도, pH변화 등의 품질적으로 크게 차이가 없었으나 감모율은 9％ 수준으로 높게 나타났다. 그리고 실험에 사용한 6가지 근채류 중에서 화학적 박피가 가장 효과적인 품목으로 가열 온도 및 시간의 영향을 크게 받지 않는 것으로 나타났다.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.2
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• pp.108-120
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• 2008

This paper discusses the prediction of deforestation areas using probability models from forest census database, Geographic information system (GIS) database and the land cover database. The land cover data was analyzed using remotely-sensed (RS) data of the Landsat TM data from 1989 to 2001. Over the analysis period of 12 years, the deforestation area was about 40ha. Most of the deforestation areas were attributable to road construction and residential development activities. About 80% of the deforestation areas for residential development were found within 100m of the road network. More than 20% of the deforestation areas for forest road construction were within 100m of the road network. Geographic factors and vegetation change detection (VCD) factors were used in probability models to construct deforestation occurrence map. We examined the size effect of area partition as training area and validation area for the probability models. The Bayes model provided a better deforestation prediction rate than that of the regression model.

• Cement Symposium
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• no.22
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• pp.97-102
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• 1994

• Cement Symposium
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• no.23
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• pp.156-164
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• 1995

• Journal of Korean Society of Transportation
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• v.32 no.2
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• pp.130-138
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• 2014

This paper assessed the weights of attributes in creating transit malls. The aim of the creation was classified as travel demand management and urban revitalization. The attributes were grouped into four aspects, or 4As: attraction, amenity, accessibility, and activity. These dimensions represented land-use, urban design, transport, and socio-cultural characteristics, respectively. The analytical hierarchy process was applied to explore the weights. Accessibility(52.7%), attraction(25.6%), amenity(13.7%), and activity(8.0%) were the order of magnitude in weights for the purpose of travel demand management, while attraction(36.1%), accessibility(30.6%), amenity(17.7%), and activity(15.6%) were that of urban revitalization. The multi criteria analysis also showed different size of weights in the sub planning attributes. These results indicate that the aimin implementingtransit malls should be differentiated and highlight that the combined land-use and transport plan is essential for the successful development. Car accessibility and socio-cultural characteristics are also understood as the important factors.

• The Journal of the Korea Contents Association
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• v.15 no.4
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• pp.350-356
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• 2015

The aim of this study is to perform simulations to design the detector module with crystal array by Monte Carlo simulation. For this purpose, a small animal PET scanner, employing module with 1~8 crystal array discrimination scheme, was designed. The proposed scanner has an inner diameter of 100 mm with detector modules in crystal array. Each module is composed of a 5.0 mm LSO crystal with a $2.0{\times}2.0mm^2$ sensitive area with a pitch 2.1 mm and 10.0 mm thickness. The LSO crystals are attached to the SiPM which has a dimension of $2.0{\times}2.0mm^2$. The detector module with crystal array of the designed PET detector was simulated using the Monte Carlo code GATE(Geant4 Application for Tomographic Emission). The detector is enough compensation for the loss of data in sinogram due to gaps between modules. The results showed that the high sensitivity and effectively reduced the problem about the missing data were greatly improved by using the detector module with 1 crystal array.

• Proceedings of the KAIS Fall Conference
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• 2001.11a
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• pp.161-162
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• 2001

본 연구는 화강석 가공공정에서 발생하는 폐잔사틀 자원으로 활용하기 위하여 화강석 폐잔사의 응집 특성에 관하여 실시한 연구이다. 이를 위하여 Al₂(SO₄)₃와 FeCl₃ 그리고 KOH, Al(OH)₃, 그리고 K₂CO₃를 사용하여 만든 용액(SK용액)을 사용하여 산성 분위기와 알칼리성 분위기에서 응집특성에 관하여 실험하였다. 응집 특성은 탁도 제거와 충전밀도를 사용하여 분석하였다.

• The Journal of the Korea Contents Association
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• v.14 no.6
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• pp.442-452
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• 2014

Using the 1st and 7th waves of KEEP(Korea Education and Employment Panel), this study explores the relationships among 212 participants' characteristics during high school, experience of taking English-mediated subject courses(EMSC) during college, career decision types, and employment status. These students' high school experiences and college experiences were used to predict the log-odds of taking and the understanding EMSC. Results of the analysis showed that none of high school characteristics such as career decision, English private education experience, interest in English, and their scholastic aptitude test score in English were associated with taking and understanding EMSC. Among college experience variables, only female students' level of understanding English subject courses was statistically significantly higher than that of male students. There were statistically significant positive associations between the understanding the EMSC and the number of the EMSC taken and also between the understanding of the EMSC and perceived usefulness of the EMSC. There was also a statistically significant relationship between career types (continuing with graduate studies vs. working) and taking EMSC, but the relationship between career types and understanding the EMSC was not statistically significant. In addition, the relationship between the experience of taking EMSC and employment status was not statistically significant.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1998.05a
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• pp.83-88
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• 1998

가스배관은 주로 도로를 따라 매설되어 있으며, 최근 지하철공사가 도심지에서 도로를 따라 지속적으로 이루어지고 있으므로 지하철공사시 기존에 매설되어 있는 가스배관이 대기로 노출되고 있다. 노출된 배관의 자중을 지탱해 주기 위하여 전용보를 설치한 후 와이어로프를 이용하여 가스배관을 전용보에 매달아 놓은 상태에서 지하구조물 공사를 하고 있으며, 도로는 임시적으로 철판으로 복공하여 사용하고 있는 실정이다. (중략)