HDPE 개질 아스팔트 혼합물의 강도 및 변형특성

김광우,이기호,권오선,고태영 강원대학교 부설 석재복합신소재 제품연구센터 2004 석재연 논문집 Vol.9 No.-

본 연구는 폐비닐 펠렛을 도로포장재료로 재활용하여 자원절약 및 아스팔트 혼합물의 품질향상을 위한 연구이다. 이를 위하여 폐비닐의 첨가량별 배합설계를 수행하여 적정 폐비닐 첨가량과 최적 아스팔트 함량으로 편마암과 화강암 2가지 골재와 폐비닐인 RHDPE의 함량을 4가지로 혼합물을 제작하여 8종류의 재질 혼합물과 2종류의 무개질 혼합물을 제작하였다. 그리고 이 공시체에 대하여 마샬안정도, 간접인장강도 및 Kim test와 반복주행시험 등 실내시험을 통하여 혼합물의 특성을 분석하였다. 폐비닐 첨가량은 RHDPE가 8%일 때 안정도와 간접인장강도 모두 가장 우수한 것으로 나타났고 취성도 나타나지 않았다. RHDPE를 첨가한 혼합물에 대하여 Kim test를 수행한 결과 DR과 DS 모두 높은 상관성을 보였다. 그리고 반복주행시험에서는 RHDPE를 첨가한 혼합물이 일반 혼합물보다 우수하였다. 향후 많은 실험을 통해 RHDPE의 우수성을 입증한다면 소성변형 저항성에 우수한 재료로 이용될 수 있을 것이다. This study is a fundamental research for recycled high-density polyethylene (RHDPE) in asphalt mixture for improving roadway pavement. Marshall mix design was conducted and optimum asphalt content(OAC) was determined for dense-graded surface course mixture by RHDPE content. Marshall stability test, indirect tensile strength (ITS) test, wheel tracking trest and Kim-test were carried out to measure the characteristics of RHDPE-added asphalt concretes. From the results of this study, RHDPE in asphalt mixture if possible. It could be considered that adding too much RHDPE in asphalt mixture is not proper. The optimum content of RHDPE was appeared to be 8%. In Kim-test, statistical analysis was performed for each loading head and aggregate to find out correlation between S_(D) values and each rut parameter. The analysis result showed that S_(D) had very high coefficient of determination with rut parameters on the average.

HDPE 폐비닐 개질 아스팔트 혼합물의 강도 및 공용 특성 연구

김광우 ( Kim Kwang Woo ),이기호 ( Lee Gi Ho ),권오선 ( Kwon Oh Sun ),조문진 ( Cho Mun Jin ) 한국농공학회 2004 한국농공학회 학술대회초록집 Vol.2004 No.-

본 연구는 폐비닐 펠렛을 도로포장재료로 재활용하여 자원절약 및 아스팔트 혼합물의 품질향상을 위한 연구이다. 이를 위하여 폐비닐의 첨가량별 배합설계를 수행하여 적정 폐비닐 첨가량과 최적 아스팔트 함량으로 편마암과 화강암 2가지 골재와 폐비닐인 RHDPE의 함량을 4가지로 혼합물을 제작하여 8종류의 개질 혼합물과 2종류의 무개질 혼합물을 제작하였다. 그리고 이 공시체에 대하여 마살안정도, 간접인장강도 및 Kim test와 반복주행시험 등 실내시험을 통하여 혼합물의 특성을 분석하였다. 폐비닐 첨가량은 RHDPE가 8%일 때 안정도와 간접인장강도 모두 가장 우수한 것으로 나타났고 취성도 나타나지 않았다. RHDPE를 첨가한 혼합물에 대하여 Kim test를 수행한 결과 DR과 DS 모두 높은 상관성을 보였다. 그리고 반복주행시험에서는 RHDPE를 첨가한 혼합물이 일반 혼합물보다 우수하였다. 향후 많은 실험을 통해 RHDPE의 우수성을 입증한다면 소성변형 저항성에 우수한 재료로 이용될 수 있을 것이다. This study is a fundamental research for recycled high-density polyethylene (RHDPE) in asphalt mixture for improving roadway pavement. Mix design was conducted by RHDPE content and optimum asphalt content (OAC) was determined for dense-graded surface course mixture. Marshall stability test, indirect tensile strength (ITS) test, wheel tracking test and Kim-test were carried out to measure the characteristics of RHDPE-added asphalt concretes. From the results of this study, RHDPE in asphalt mixture is possible. It could be considered that adding too much RHDPE in asphalt mixture is not proper. The optimum content of RHDPE was appeared to be 8%. In Kim-test, Statistical analysis were performed for each loading head and aggregate to find out correlation between SD values and each rut parameter. The analysis result showed that SD had very high coefficient of determination on the average with rut parameters.

산업폐수처리장 방류수의 내분비계 장애작용 평가

오승민,김기서,유병택,장형석,이희성,정규혁 한국환경독성학회 2004 환경독성보건학회지 Vol.19 No.4

This study was designed to investigate potential endocrine disrupting effects of several industrial wastewater effluents discharged from cosmetic, plaiting, paint, textile industry using EROD bioassay and E-Screen assay The results of E-screen assay showed that textile industrial wastewater could act as a full agonist and cosmetics and plaiting industrial wastewater could act as a partial agonist On the contrary, the wastewater discharged from paint industry did not show any estrogenic effect Estrogenic activity in the effluents of cosmetic and paint industrial wastewater was lower than that in the influents indicating that the wastewater treatment process minimized the effects of discharges on water quality Despite of these results, it was recognized that wastewater treatment was not always minimize toxic impact In this study, increased estrogenic effect was observed in the effluents of plating and textile wastewater, and EROD activity was increased in the effluents of cosmetic and plating wastewater.

일반중학생의 통합체육에 대한 태도 연구

오광진,최승권,김기영 한국특수체육학회 2002 한국특수체육학회지 Vol.10 No.1

the purpose of this study was to examine the middle school students' attitude toward inclusive physical education of students with disabilities. Subjects for this study was middle school students of 7-9 grades living in Seoul, South Korea The sample number used in the analysis was 497. The questionnaire concerning the middle school students' attitudes toward inclusive physical education was developed by Kwang-Jin Oh(2001) who consisted of 6 factors, 26-item. The reliability of the questionnaire was confirmed based on the calculation of Chronbach's α value. Chronbach's α value was .8753. This study produced the following results. First, the middle school students' attitudes toward inclusive physical education of students with disabilities according to gender, grades, experience of inclusive education, having friends with disabilities, and experience of inclusive physical education had significant differences. Second, gender and start of inclusive physical education had negative effects on attitude toward inclusive physical education of students with disabilities. These findings reported the middle school students contacted with students with disabilities had negative attitudes toward inclusive physical education.

점진적 코드생성에 관한 연구

김기원,임청규,오상봉 大田大學校 産業技術硏究所 1993 산업기술연구소 論文集 Vol.1993 No.6

본 논문에서는 복합프로그래밍 지원 환경에서 필요한 점진적 코드생성에 관한 연구를 하였다. 점진적 코드생성은 프로그램의 수정후 불 일치한 트리가 발생되었을 때 최소한의 트리를 방문하여 항상 수행 가능한 프로그램 상태를 유지할 수 있게 해준다. 또한 대상 언어에 대한 구문을 미리 인식하고 있어 구문 오류가 발생될 때 마다 즉각 수정이 가능하며, 정적 의미 분석은 context-free 또는 context-sensitive에 대한 오류를 방지할 수 있다. 본 논문에서는 점지누적 애트리뷰트 평가 알고리즘을 사용하여, 추상구문 트리에 p-code를 첨가하여 점진적 코드생성을 실험하였다. This paper is a study concerned with incremental code-generation which is in need of state which supports integrate programming environments. When after modification of the program the inconsistent tree is found, the incremental code-generator moves minimal tree and then makes the state of program capable of execution and keep it. The incremental code-generation recognized already the syntax of language. When the syntax errors occur, the program can modify immediately. Syntatic analysis can protect against context-free and context-sensitive errors. This paper uses incremental attribute evaluation algorithms and then research into incremental code-generation with abstract syntax tree adding p-code.

벗나무속 수종간의 핵 리보솜 DNA의 ITS Ⅰ 염기서열 비교

오유성,김기옥,정용환,오문유,한상현,고미희 제주대학교 생명과학연구소 1998 제주생명과학연구 Vol.1 No.-

Comparison of four species (Prunus yedoensis, P. sargentii, P. pendula for. ascendens, P. serrulata var. quelpaertensis) and one cultivar of P. yedoensis were carried out by comparing their nucleotide sequences from the internal transcribed spacers (ITS) I of nuclear ribosomal DNA (rDNA). The length of the ITS I region was ranged from 229 to 236 base pairs (bp). The G+C contents of ITS I ranged from 58.5 to 60.2%. The value of nucleotide divergence across for four Prunus species and one cultivar ranged from 0.4 to 6%. The pairwise distance between P. pendula for. ascendens and P. yedoensis was 0.004 showing the lowest value among any other pairs. On the other hand, the pairwise distance betwen P. yedoensis and cultivated P. yedoensis was 0.026. The nucleotide analysis based on ITS I sequence was considerably similar to previous studies on the basis of random amplified polymorphic DNA (RAPD).

제주먹초파리(Drosophila sp ; Robusta Group)에서 난황 단백질 합성에 미치는 유충 호르몬Ⅲ(Juvenile hormone Ⅲ)의 영향

김기옥,오문유,김세재 濟州大學校 基礎科學硏究所 1992 基礎科學硏究 Vol.5 No.1

제주먹초파리 (Drosophila sp: robusta group)에서의 난황 단백질 합성은 우화 후 2일된 female 성체의 지방체와 난소의 여포세포 (follicle cell)에서부터 합성되기 시작했다. 그리고 합성된 난황 단백질은 hemolymph로 방출된 후 선택적으로 난소로 흡수되어 완전히 성숙한 embryo를 생성하는데는 우화 후 약 4일정도가 소요되었다. 난황 단백질 유전자 발현은 곤충 호르몬인 20-hydroxyecdyson(20HE)과 juvenile hormone (JH)에 의하여 조절된다. 미성숙한 female성체에서 복부만을 분리하여 10-6M에서 10-3M의 juvenile hormoneⅢ 을 0.3 ㎕정도 주입하여 난황단백질을 합성을 유도 할수 있었다. 그리고 10-3M의 JHⅢ 처리후 2-3시간 사이에 난황 단백질의 합성을 추적할 수 있었다. 우화 후 2일된 female 성체에 수종의 호르몬 (Acetone, JHⅢ, JHⅢ-20HE)을 처리한 결과 난소의 발달 효과는 JHⅢ 처리구에서 가장 높았다. 따라서 JHⅢ는 vitellogenesis동안에 지방체와 여포세포에 있는 난황 단백질 유전자를 활성화시킴은 물론 난소의 발달에도 많은 영향을 미치는 것으로 보인다. Three yolk proteins of Drosophila sp (robusta group) begin to be synthesized in fat body and ovarian follicle cells of two female after eclosion, and selectively accumulated by the oocyte during vitellogenesis. Expression of the yolk protein genes are regulated by the insect hormone, each as 20-hydroxyecdyson and juvenile hormone. An injection of 0.3 ㎕ of 10-6 M JHⅢ in one day-old female was sufficient to promote synthesis and secretion of yolk proteins in isolated abdomens. Three yolk proteins were first detected between 2 and 3 hrs after treated of 10-3 M JHⅢ in abdomens removed from the whole body of one day-old female flies. The vitellogenin oocytes development by treatment with some hormones (acetone, JHⅢ, and JHⅢ-20HE) was highly affected in JHⅢ of 2-day old female flies after eclosion. Thus it seems like that increase juvenile hormone levels not only switches on yolk protein genes during vitellogenesis but also promotes the oocytes development.

4루트 방식에 의한 방전관용 안정기 개발

이오걸,김태우,김종기,송호신,이준탁 동의공업대학 2000 論文集 Vol.26 No.1

This paper was development a discharge tube ballast by 4 root method in order to wave improvement of high power factor and high efficiency. The discharge tube ballast consists of a power factor correction circuit and a correction circuit on switching frequency of inverter. Instead of passive power factor circuit, active power factor circuit is adopted. Because it has the advantage of size. weight, total harmonic distortion, out DC voltage regulation, and power factor. The power factor circuit with MG34262 is controlled by variable frequency discontinuous mode. Results experiments, discharge tube ballast by 4 root method showed to have excellent in the discharge tube ballast's operation and characteristics.

울산ㆍ온산 지역 토양 중의 중금속 분포 특성

고영국,오영희,김영복,정기호 부산대학교 환경문제연구소 1999 環境硏究報 Vol.17 No.1

인공 치아우식 발생 모델에서 디지털 방사선 공제술을 이용한 인접면 치아우식증의 진단

박정훈,최용석,황의환,이기자,최삼진,박영호,김경숙,진현석,홍경원,오범석,박헌국 대한구강악안면방사선학회 2009 Imaging Science in Dentistry Vol.39 No.1

Purpose : The purpose of the experiment was to evaluating the diagnostic ability of dental caries detection using digital subtraction in the artificial caries activity model. Materials and Methods : Digital radiographies of five teeth with 8 proximal surfaces were obtained by CCD sensor (Kodak RVG 6100 using a size #2). The digital radiographic images and subtraction images from artificial proximal caries were examined and interpreted. In this study, we proposed novel caries detection method which could diagnose the dental proximal caries from single digital radiographic image. Results : In artificial caries activity model, the range of lesional depth was 572-1,374 μm and the range of lesional area was 36.95-138.52mm². The lesional depth and the area were significantly increased with demineralization time (p<0.001). Furthermore, the proximal caries detection using digital subtraction radiography showed high detection rate compared to the proximal caries examination using simple digital radiograph. Conclusion : The results demonstrated that the digital subtraction radiography from single radiographic image of artificial caries was highly efficient in the detection of dental caries compared to the data from simple digital radiograph.