• 한국환경복원기술학회지
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• 제18권1호
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• pp.115-125
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• 2015

This study was carried out to analyze comparison of carbon storage and physicochemical properties of vegetation soil for extensive green rooftop established at Seoul National University in september 2013. For this study, 42 plots were made by 2 kinds of vegetation soil including A-type and B-type. A-type vegetation soil plots were made of 90% perlite and 10% humus and B-type vegetation soil plots were made of 60% perlite, 20% vermiculite, 10% coco peat and 10% humus. This study used 6 kinds of plants which are Aster koraiensis, Sedum takesimense, Zoysia japonica Steud, Euonymus japonica, Rhododendron indicum SWEET and Ligustrum obtusifolium. Field research was carried out in 11 months after planting. Physiochemical properties of B-type vegetation soil plots were better than A-type vegetation soil plots in every way and soil carbon content was also higher at B-type vegetation soil plots as well. B-type vegetation soil plots were maintained 10 to 20% higher soil water content than A-type vegetation soil plots of the study period. The species of herb which showed the best carbon storage was Zoysia japonica Steud at B-type vegetation soil plots. The species of shrub which showed the best carbon storage was Ligustrum obtusifolium at B-type vegetation soil plots. Plants generally showed better growth at B-type vegetation soil plots and B-type vegetation soil plots were higher than A-type vegetation soil plots in soil carbon stock.

• 한국농공학회논문집
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• 제60권4호
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• pp.1-13
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• 2018

The grain complex of Saemangeum is created for promoting the foundation of agriculture combined the global competitiveness. However, the masterplan is being also revised with changing of local conditions and social needs. Thus, the dynamic masterplan is needed to consider the change of time for Saemangeum project. The present study was made to set up the dynamic masterplan of Saemangeum grain complex for handling the change such as project progress, local environment, and project conditions flexibly. In this study, the dynamic masterplan for the progressive development of water supply, farmland composition, and introduction facilities is presented to the 6-2 zone in three stages. We believed that the water supply would be possible through the pumping and desalination facilities with the development stages. The farmland composition proceeded for each complex with reclamation, soil preparation, and soft soil processing. And it is planned to carry out crop cultivation from the complex where the construction is completed first. The introduction facilities were analyzed focusing on the silos and forage loading facilities, and the optimal location of them was selected using road and accessibility. The concept of dynamic masterplan may provide the direction for the planning and progress of reclamation project.

• 농촌계획
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• 제23권4호
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• pp.49-59
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• 2017

The importance of information system evaluation has increased according to ICT development and this evaluation is required for objective verification. The aim of this study is to develop evaluation indicators for web-based information system and verify the availability of these evaluation indicators through applying to agricultural water integrated information system. This study finds and provides eight evaluation items and 64 indicators for a web-based information system using $3{\times}3$ Mandal-Art matrix that is a tool for creating creative ideas. These evaluation items are design, contents, navigation, stability, community, convenience, usefulness, and accuracy. Total 64 evaluation indicators were presented by deriving eight evaluation items for each using $9{\times}9$ Mandal-Art matrix. When evaluating information system using evaluation indicators, it can be identified the vulnerable items in the information system. Also, the comprehensive results of the information system could be understood when appearing a single score after weighting. In addition, it can also help to prepare a questionnaire for evaluation systematically.

• 한국농공학회논문집
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• 제64권2호
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• pp.47-55
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• 2022

The objective of this study was to analyze the effect of the duration and time distribution of probability rainfall on farmland inundation for the paddy fields in the drainage improvement project site. In this study, eight drainage improvement project sites were selected for inundation modeling. Hourly rainfall data were collected, and 20- and 30-year frequency probability rainfalls were estimated for 14 different durations. Probability rainfalls were distributed using Intensity-Duration-Frequency (IDF) and Huff time distribution methods. Design floods were calculated for 48 hr and critical duration, and IDF time distribution and Huff time distribution were used for 48 hr duration and critical duration, respectively. Inundation modeling was carried out for each study district using 48 hr and critical duration rainfalls. The result showed that six of the eight districts had a larger flood discharge using the method of applying critical duration and Huff distribution. The results of inundation depth analysis showed similar trends to those of design flood calculations. However, the inundation durations showed different tendencies from the inundation depth. The IDF time distribution is a distribution in which most of the rainfall is concentrated at the beginning of rainfall, and the theoretical background is unclear. It is considered desirable to apply critical duration and Huff time distribution to agricultural production infrastructure design standards in consideration of uniformity with other design standards such as flood calculation standard guidelines.

• 한국철도학회논문집
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• 제20권1호
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• pp.1-10
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• 2017

제동 스킬소음은 승객과 선로 주변의 주민에게 불편을 끼쳐 시급히 해결해야 할 문제의 하나이지만 해결책을 찾는 것은 쉽지 않다. 제동 스킬소음을 저감하기 위한 해결책은 크게 제동 마찰재의 소재를 개량하거나 제동패드의 구조를 개선하는 것으로 구분할 수 있다. 본 연구에서는 현재 KTX 차량에 사용되고 있는 제동패드를 기준으로 마찰재의 소재만을 바꾼 패드와, 동일한 마찰재 소재를 사용하지만 구조를 유연형으로 바꾼 제동패드를 제작하여 제동 다이나모미터에서 다양한 조건으로 마찰특성과 소음특성을 평가하고 영업차량이 역에 정차할 때 측정한 스킬소음과 비교 및 분석하였다. 제동 다이나모미터 시험이 실차 시험을 어느 정도 재현하는 것이 가능한다는 것을 발견하였고, 영업열차에서 최고 스킬소음이 발생한 4,500Hz 대역의 스킬소음은 다이나모미터 시험에서도 정확히 일치하고, 이 주파수는 제동디스크의 고유진동수와 일치하는 것을 규명하였다. 제동 스킬소음이 발생하는 주파수는 캘리퍼에 작용하는 압력, 시험온도, 그리고 제동 초속도에 따라 달라지지만 일정한 경향을 보여주지는 않았다. 개발된 제동패드의 평균 마찰계수는 0.35~0.45의 범위에 있고 마찰재 소재만을 바꾼 경우는 21.6dB(A), 구조를 변경한 경우는 17.3dB(A) 만큼 최대 소음을 줄일 수 있었다.

• 한국가스학회지
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• 제21권6호
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• pp.88-95
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• 2017

국내에서 독성가스의 사용은 반도체, 디스플레이 및 태양광 등 첨단산업의 발전에 따라 증가하고 있는 추세이다. 최근 5년간 국내 독성가스 소비량 현황을 살펴보면 연평균 12% 정도 증가 추세에 있지만, 아직까지 사용에만 관심이 집중되고 있고, 사후 처리나 안전에는 다소 소홀한 것이 사실이다. 2012년 9월 발생한 구미 불산 누출사고는 이러한 안전관리 부재를 단적으로 보여주는 사례이다. 이 사고로 인하여 정부, 업계 및 학계에서는 화학물질(독성가스) 누출사고 등에 대한 관심을 갖게 되었고, 정부 주도로 화학물질안전관리대책 등이 수립되어 추진되어 왔지만 아직까지 안전관리 사각지대가 많은 실정이다. 본 연구에서는 반도체, 디스플레이 업종에서 사용되는 저감설비에서 배출되는 가스상 물질에 대한 처리효율에 대한 효과적인 측정방법을 개발하는 것이 목적이다. 국립환경과학원과 UNFCCC에서 제시하는 반도체 & 디스플레이 업종에서 사용되는 온실가스 저감시설의 처리효율 측정방법 가이드라인에 대해 실증시험을 통해 맹독성가스 시설에도 오차 범위 내에서 적용 가능한지를 살펴보고 맹독성가스 저감시설에 대한 차별화된 효율성 측정 방법을 제시하였고, 독성가스 사고에 대한 선제적 예방을 위해서 독성가스 저감시설 등 안전설비에 대한 제3자 인증제도 도입의 필요성을 제안하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.496-504
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• 2011

The region trunk line railroad route undergoes an influence on a large scale in train operation systematic reorganization. This keynote of the train operation not being to the consumer and not to be is because being to the supplier. The trunk line route user of region supply change of the supplier sensitively, accepts but, the demand unit will be able to change the supply massive demanders does not become and like that to accept this back is not the railroad the mean of transportation which grudge is different a mean of transportation mainly makes use. This hits to neither the gist of GLORY promotions of the railroad public corporation which pursues the railroad use which is ordinary even in the basis of governmental policy of stock of coal small green growth and not to be is arranged. For the railroad use activation of the region trunk line route consequently and to excavate the demand hindrance element and a demand lure element the inside and the outside defines and to observe the fluctuation of use importing in existing train operation systematic fluctuation, with the user tries analyzes the instance of the overseas railroad enterprise about the process which reflects the opinion of the area and improvement under preparing boil.

• 농촌지도와개발
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• 제2권1호
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• pp.71-79
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• 1995

The rural extension in Korea faces transient period since Green Revolution. The urban-centered rapid industrialization policies have initiated the changes in rural and agricultural sector. Nowadays, the World Trade Organization (WTO), newly established by the agreement of the Uruguay Round (UR), is accelerating the changes in rural areas. The rural structural adjustment program established in 1990, in order to cope with the internal and external changes encompassing rural Korea. The rural structure adjustment program is a political responses to reduce the development gaps among industries and regions within the country and to reinforce the price competitiveness of agricultural products toward trade liberalization. This study aims to apply the contents and principles of the rural structural adjustment program for the extension education. It argues that the rural extension should play a pivotal role to gather, process, and deliver the information related to the rural structural adjustment initiating rapid rural social changes. It suggests that the rural extension services should deal with the development of industries through introducing business management techniques and linking relevant laborers, and the education and employment guidance of potential employees as well as the technological assistance on farm management to farmers.

• 설비공학논문집
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• 제27권1호
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• pp.39-43
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• 2015

The Energy and Green House Gas target management system was launched by the Korean Government in 2010. The Korea Emission Trading System will start in 2015. Therefore, simultaneous pursuit of energy saving and greenhouse emission reduction through energy use rationalization is an important obligation of Korean engineers, who import about 97% of domestic energy consumption. Economic analysis of the GHG emission reduction methodologies registered and approved by Korea Voluntary Emission Reduction (KVER) program was conducted. The results for waste heat recovery employed in an energy intensive pulp, paper and wood industry were reported. The emission reduction intensities were 9.7 kg $CO_2$/ton_pulp production. Net Present Value analysis showed that the GHG emission reduction was economically beneficial with an internal rate return of 60%. The results of exergy analysis indicated that the second law efficiencies of waste heat recovery system employed in KVER program were 77.3% and 53.6%. NPV decreased as the exergy decreased.

• 한국자동차공학회논문집
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• 제14권6호
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• pp.17-23
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• 2006

Rubber materials have the nonlinear, large deformation and viscoelastic behavior. W.D. Kim et al. studied these characteristics through the static, fatigue, dynamic, aging and viscoelastic test. This paper discussed that the properties of engine mounting rubber, such as static stiffness, fatigue life and damping factor, are predicted based on CAE by using material properties acquired by the report of Kim et al. In result, the static stiffness of engine mounting rubber is predicted approximately in comparison with test value. Also, it was confirmed that the relationship of fatigue life and Green-Lagrange strain in specimen was the valid tool to predict the fatigue life of engine mounting rubber. From the results of transient viscoelastic analysis the damping factor changed rapidly at the range less than 8hz.