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A Preliminary Study for Identifying Soil Management Area in Environmental Impact Assessment on Development Projects (개발사업 환경영향평가 시 토양중점관리지역 선정을 위한 예비연구)

  • Kim, Jong Sung;Kim, Choong Ki;Yoo, Keunje;Hwang, Sang-Il
    • Journal of Environmental Impact Assessment
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    • v.26 no.6
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    • pp.457-469
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    • 2017
  • In order to conserve soil functions to the highest degree in development projects, it is necessary to identify and manage specific area (so called soil management area) including soils with good or excellent functions. Therefore, in this work, we conducted a preliminary study how to identify soil management area in environmental impact assessment on development projects. To do this, quantitative evaluation was carried out on two example projects, using InVEST model considering a couple of soil functions, i.e., erosion control and carbon sequestration functions. Then, soil management area was identified through overlay analysis. The methodology developed in this study is able to be used widely for more detailed analysis with high resolution and furthermore overlay anaysis with other assessment items. For more perfect assessment, other soil fuctions needed to be taken into account into our methodology.

A Kinetic Study of Thermal-Oxidative Decomposition of Waste Polyurethane (폐폴리우레탄의 열적 산화분해에 대한 속도론적 연구)

  • Jun, Hyun Chul;Oh, Sea Cheon;Lee, Hae Pyeong;Kim, Hee Taik
    • Applied Chemistry for Engineering
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    • v.17 no.3
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    • pp.296-302
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    • 2006
  • The kinetics of the thermal-oxidative decomposition of waste polyurethane (PU) according to oxygen concentration has been studied using a non-isothermal thermogravimetric technique at several heating rates from 10 to $50^{\circ}C/min$. A kinetic model accounting for the effects of the oxygen concentration by the differential and integral method based on Arrhenius equation was proposed to describe the thermal-oxidative decomposition of waste PU. To obtain the information on the kinetic parameters such as activation energy, reaction order, and pre-exponential factor, the thermogravimetric analysis curves and its derivatives have been analyzed using the kinetic analysis method proposed in this work. From this work, it was found that reaction orders for oxygen concentration had a negative sign, and activation energy decreased as the oxygen concentration increased. It was also found that the kinetic parameters obtained from the integral method using the single heating rate experiments varied with heating rates. Therefore, it is thought that the differential method using the multiple heating rate experiments more effectively represents the thermal-oxidative decomposition of waste polyurethane.

Lane Extraction through UAV Mapping and Its Accuracy Assessment (무인항공기 매핑을 통한 차선 추출 및 정확도 평가)

  • Park, Chan Hyeok;Choi, Kyoungah;Lee, Impyeong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.34 no.1
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    • pp.11-19
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    • 2016
  • Recently, global companies are developing the automobile technologies, converged with state-of-the-art IT technologies for the commercialization of autonomous vehicles. These autonomous vehicles are required the accurate lane information to enhance its reliability by controlling the vehicles safely. Hence, the study planned to examine possibilities of applying UAV photogrammetry of high-resolution images, obtained from the low altitudes. The high-resolution DSM and the ortho-images were generated from the GSD 7cm-level digital images that were obtained and based on the generated data, when the positions information of the roads including the lanes were extracted. In fact, the RMSE of verifying the extracted data was shown to be about 15cm. Through the results from the study, it could be concluded that the low alititude UAV photogrammetry can be applied for generating and updating a high-accuracy map of road areas.

Characteristics of Diamond Like Carbon Thin Film Deposited by Plasma Enhanced Chemical Vapor Deposition Method with Gas Flow Rate and Radio Frequency Power (가스 유량과 RF Power에 따라 PECVD 방법으로 증착된 DLC 박막의 특성)

  • Jeong, Seon-Yeong;Kim, Hyeon-Gi;Ju, Seong-Hu
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2018.06a
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    • pp.88-88
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    • 2018
  • DLC(Diamond Like Carbon) 박막은 높은 열전도도, 큰 전기저항, 높은 강도 등의 다이아몬드와 유사한 특성을 가지고 있으면서 저온 저압에서도 합성이 가능하고, 합성 조건에 따라 물리 화학적 특성도 넓게 조절 할 수 있으며 상대적으로 넓은 면적에서 균일하고 평활한 박막의 합성이 가능하여 산업적 응용 면에서도 경쟁력을 갖추고 있다[1]. 이러한 DLC 박막을 합성함에 있어서 RF-PECVD(Radio Frequency Plasma Enhanced Chemical Vapor Deposition) 방법은 PECVD 방법 중 가장 보편적으로 사용되고 또 캐패시터 타입의 RF-PECVD 방법은 균일한 대면적 증착과 대량생산이 가능하다[1,2]. 본 연구에서는 우수한 특성을 갖는 DLC 박막의 증착 조건을 찾기 위해 캐패시터 타입의 RF-PECVD를 사용하여 공정 가스의 유량과 RF Power를 변화하여 박막을 증착하고, 증착된 박막의 특성을 연구하였다. DLC 박막은 ITO(Indium Tin Oxide) 유리 기판 위에 $100^{\circ}C$에서 5 min 동안 아세틸렌($C_2H_2$) 가스를 사용하여 가스 유량과 RF Power를 변화하여 증착하였다. 증착된 DLC 박막의 특성은 투과도, 평탄도, 두께를 측정하여 비교하였다. 가시광선 영역(380-780 nm)에서 투과도를 측정한 결과 ITO 유리 기판을 기준으로 한 DLC 박막의 투과도는 가시광선 영역 평균 94.8~98.8% 사이의 값으로 매우 높은 투과율을 나타내었다. 투과도는 가스 유량이 증가함에 따라 증가하는 경향을 나타내었고, RF Power의 변화에는 특정한 변화를 나타내지 않았다. 박막의 평탄도($R_a$, $R_{rms}$)와 두께는 AFM(Atomic Force Microscope)을 사용하여 측정하였다. 평탄도 $R_{rms}$는 0.8~3.3 nm, $R_a$는 0.6~2.5 nm 사이를 나타내었고 RF Power와 가스 유량의 변화에 따른 경향성을 나타내지는 않았다. 두께는 RF Power 25 W에서 55 W로 증가함에 따라 증가하는 경향을 나타내었으나 70W에서는 가스의 유량에 따라 상이한 결과를 나타내었다.

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Stabilization of Rhizosphere pH during Tomato Cultivation Using Expanded Rice Hull Substrate (양액재배용 평연화 왕겨 배지의 근권 pH 안정화)

  • 임상현;김경희;전신재;유근창
    • Journal of Bio-Environment Control
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    • v.10 no.2
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    • pp.95-100
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    • 2001
  • In countries that consumes rice as a main staple, rice hulls are natural resources composed of a large amount of organic compounds and high uniformity in size. Rice hulls are expanded to get rid of a defect in untreated rice hulls and to be used as a hydroponic substrate. Research on rice hulls is continuing for the agricultural application. This research was conducted to stabilize rhizosphere pH of the expanded rice hull substrates because of high pH caused by repeated use in ERH(expanded ride hull) substrates and without increasing the cost of developing new substrates. Sphagnum peatmoss (pH 3.0-4.0) wee mixed with the expanded rice hull substrate in the ratio of 10% (v/v), and this ratio kept the pH range of 6.0 to 6.5 in the root area of tomato plants during growth and at the time of harvest of tomato fruits. Also absorbtion of nutrients was highly increased. The yield increased from 1,051 to 1,266 kg per tomato plant which were harvested by two clusters.

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Development of Forest Ecosystem Assessment Technique of Environmental Impact Assessment(II) : Nature Evaluation of Vegetation (환경영향평가중 삼림생태계 평가기법개발(II) : 녹지의 자연성평가)

  • Choi, Song-Hyun;Lee, Kyong-Jae
    • Journal of Environmental Impact Assessment
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    • v.5 no.2
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    • pp.33-47
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    • 1996
  • To select the criteria, literature review was made in the quantitative case of conservation biology, foreign country's EIA and domestic ecology. Among them, a few factors was extracted. To applicate the criteria to domestic forest ecosystem, expert opinion survey was executed to the ecologist. The results were summarized as follows; 1. Classification of sites was made of land use system which is related to forest ecosystem or forest conservation. Sites are divided into 3 categories which are nature preservation area, seminature preservation area and urbanized area. Evaluation criteria is consisted of rarity and naturalness. 2. Each area had different criteria composition according to the site characteristics. Criteria of nature preservation area is rarity in the broad sense (distribution pattern of vegetation), vegetation size, successional stage and depth of organic matters. Those of seminature preservation area are rarity in the broad sense (distribution area of vegetation), vegetation size, successional stage, diameter at breath height and depth of organic matters. And those of urbanized area are vegetation distribution in area, successional stage, age of forest and diameter of breath height. The basic data of criterion was gathered by field survey. 3. Evaluation index and total naturalness index was obtained by adding the each criterion. It is made up of two categories-rarity and naturalness. TNi is divided into 3 grades. Grade I is more than 70% for TNi, grade IT is 50~70%, and grade III is below 50%. According to the each grade, permitted action and facilities were suggested.. This research just focuses on the evaluation of vegetation quality and the assessment results do not directly judge conservation or development. To make better evaluation criteria, various fields of forest ecosystem-geological or physical nature environment and fauna ecosystem etc. -will be added wholly to this research.

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A Study on the Misconceptions in the Self-directed Learning Using a Mathematics Digital Textbook: Focused on the Division of Fractions (수학과 디지털교과서 자기주도적 학습에서 나타난 오개념에 대한 연구: 분수의 나눈셈을 중심으로)

  • Heo, Hae-Ja;Choi, Jeong-Im
    • School Mathematics
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    • v.11 no.4
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    • pp.643-664
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    • 2009
  • This study was aimed to understand the problems that students experience during the self--directed study of a mathematics digital textbook and to find the implications for the design of digital textbook. For this study, we analyzed the process of self-directed learning on 'division of fractions with same denominator' using digital textbook by eight 6th graders. Students asked to use think aloud method while they study the unit. Their learning process was videotaped and analyzed by researchers after the experiment. After the self-directed learning, students filled out a test items and participated interview with a researcher. The result showed that students experienced several misconceptions and errors while using a digital textbook. The types of misconceptions and errors were cataegorized as "misconceptions and errors caused by a mathematics textbook" and "misconceptions and errors caused by a digital textbook". Especially, students showed several important misconceptions and errors because of the design factors. This implies we need to consider the causes of misconceptions for the design of a digital textbook.

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Analysis of Forest Fire Occurrence in Korea (한국의 산불발생 실태분석)

  • Lee, Si-Young;Lee, Hae-Pyeong
    • Fire Science and Engineering
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    • v.20 no.2 s.62
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    • pp.54-63
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    • 2006
  • The number of forest fire under various conditions such as year, month, time, day of the week, region, damaged species, cause, and damaged area are checked, and the statistics of the forest fire causing materials in recent 14 years ('91-'04) are analyzed. The result shows that the year majority of forest fires had happened in last 14 year was 2001 and most of forest fire occurred in April, Sunday, around 14:00 to 15:00. The most damaged region is Gyeongsangbuk-Do, followed by Gangwon-Do, Jeollabuk-Do, and Gyeonggi-Do. The most damaged species is pine tree. The main causes of forest fires are accidental fire and incineration of a field boundary; however, recently, incendiarism is increased. The result of analysis on the damaged area shows that small fires under 5 ha occurred most frequently and large fires (over 30 ha) occurred mostly in Kangwon province (44.2%). The result also shows that the large forest fires (1,113 minutes) require 7.5 time more than the small forest fires (148 minutes). Especially, since average damaged area caused by large forest fire was about 470 ha per incident.

Development of the Bibliographic Information Network Prototype for Biology and Life Science (생명과학 문헌정보 네트워크 프로토타입 개발)

  • Ahn, Bu-Young;Song, Chi-Pyoung
    • Journal of Information Management
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    • v.36 no.2
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    • pp.125-151
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    • 2005
  • The eight types of Korean bibliographic information of biology and life science are included in PubMed that serves universal medical bibliographic information. Other domestic bibliographic information are served on its own format at different organizations. To fulfill the CCBB homepage user's request that it is necessary that integration of bibliographic service for quick acquisition of research information, we intends to construct metadata registry and service about bibliographic information of biology and life science. This paper describes the design and implementation of bibliographic information network prototype for biology and life science that can be used to share latest research result, seminar presentation data, research note, and research paper etc as well as to exchange information between researchers through Open Archiving Community.

Analysis of the Causes of Casualties of Jecheon Sports Center Fire - Focus on an Initial Response and Management - (제천 스포츠센터 화재의 다수 사상자 발생원인 분석 -초기대응과 관리적인 측면을 중심으로-)

  • Lee, Eui-Pyeong
    • Fire Science and Engineering
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    • v.32 no.5
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    • pp.57-66
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    • 2018
  • A sports center fire in Jecheon that caused 29 deaths and 40 injuries was analyzed based on initial response and management in order to investigate the causes of the casualties. The aspects of initial response included delay of reporting 119, not being guided to the exit for the body scrubber on the $2^{nd}$ floor for escape, opening the fire doors of the exits on the $1^{st}$ floor and $3^{rd}$ floor, not closing the fire door of the main stairs on the $3^{rd}$ floor, and not doing an emergency broadcast. The management aspects included closing the alarm valve of the sprinkler system on the $1^{st}$ floor, starting-stop of the fire pump controller, neglecting leakage of water and electricity between the false ceiling and ceiling in the parking lot, hiding the exit light in the ladies bathroom lounge on the $2^{nd}$ floor and piling up things in the exit, neglecting the button of an automatic door on the $2^{nd}$ floor, conventional fire safety management, insufficient inspection of fire equipment, and not working fire shutters and smoke exhaust windows.