• 제목/요약/키워드: Marshall

검색결과 261건 처리시간 0.025초

CRM 아스팔트의 최적 혼합비와 환경친화적 특성 (Environmental Friendly Characteristics of CRM Asphalt Concrete and Optimal Mixing Ratio)

  • 류병로;한양수
    • 한국환경과학회지
    • /
    • 제10권4호
    • /
    • pp.311-314
    • /
    • 2001
  • The asphalt mixture with CRM(Crumb Rubber Modifier) is known to show a better performance in resisting thermal cracking, fatigue cracking and rutting compared with the conventional mixture. The laboratory tests on the physical characteristics of indirect tensile strength, density, flow and Marshall value of the CRM asphalt were conducted. The test results show that CRM asphalt has better physical characteristics than that of conventional asphalts. And the analysis on the noise reduction effect, penetration capacity from the field test on the national road in Haksan of Chungbuk, and recycling of tire waste were conducted. From this study, the results show that 1% CRM asphalt has higher the noise reduction effect and penetration capacity that those of conventional asphalts. And, optimal contents of crumb rubber modifier in the asphalt binder is one percent. In this case, crumb rubber modifier were used 10 kg to make the asphalt binder of one cubic meter. So it was named as Eco-asphalt.

  • PDF

미국 NASA 주관 대학생 로켓 경진대회 : NASA Student Launch 사례 분석 (Analysis of NASA Student Launch as a NASA Managed University Rocket Competition)

  • 이훈희;윤용식;민경주
    • 항공우주기술
    • /
    • 제13권1호
    • /
    • pp.129-141
    • /
    • 2014
  • 미국 NASA는 자국 우주발사시스템 분야 인력양성을 위해 대학생 대상의 로켓 경진대회를 2006년부터 매년 개최하고 있다. 본 논문은 교육 프로젝트 일환으로 미국 젊은이들에게 우주 임무에 필요한 과학, 기술, 공학, 수학(STEM) 분야에 관심을 고취시키기 위한 NASA 주관 대학생 로켓 경진대회인 NASA Student Launch에 대한 의미와 운영 방식에 대한 분석을 한다. 아울러 국내 대학생 로켓 경진대회 활동을 간략히 소개한다.

고온 고압기류중을 비행하는 파라핀계 연료액적의 증발에 관한 연구 (An experimental study on the evaporation of paraffin family fuel droplet under high temperature and high pressure)

  • 정성식
    • 대한기계학회논문집
    • /
    • 제15권6호
    • /
    • pp.2125-2131
    • /
    • 1991
  • 본 연구에서는 고온고압의 기류중에 투입된 미소연료액적의 증발에 관한 정보 를 구하여 분무연소기구의 해명을 위한 기초테이터를 제공하려 시도한다.

Developing Environmental Quality Deployment for Designing Environmentally Friendly Product

  • Lee, Dong-Won;Kim, Youn-Sung
    • 품질경영학회지
    • /
    • 제31권2호
    • /
    • pp.40-50
    • /
    • 2003
  • This study proposes Environmental Quality Deployment (EQD) by combining an instrument for measuring customer satisfaction (ENVIROQUAL) with a standard tool of product design in manufacturing called quality function deployment (QFD). The EQD presents the conceptual map of House of Environmental Quality as a means to implementation to help a company know what customers perceive as important in making environmentally friendly product and provide a framework for the translation of customer satisfaction into identifiable and measurable conformance specifications for environmentally friendly product design.

아스팔트 콘크리트에 적정 폐비닐 첨가량 결정에 관한 실험적 연구 (Experimental Study for Determination of Optimum Waste Vinyl Contents in Asphalt Concrete)

  • 김광우;김주인;이순제;최선주
    • 한국농공학회지
    • /
    • 제44권5호
    • /
    • pp.88-95
    • /
    • 2002
  • This study is a fundamental research for recycling waste vinyl (WV) in asphalt mixture for improving roadway pavement. Mix design was conducted by WV content and optimum asphalt content (OAC) was determined for dense-graded surface course mixture. Marshall stability test, indirect tensile strength (ITS) test and wheel tracking test were carried out to measure the characteristics of WV-added asphalt concretes. From the results of this study, recycling WV in asphalt mixture is possible. However, as WV content increased, melted WV clustering appeared in asphalt mixture. It could be considered that adding too much WV in asphalt mixture is not proper. The proper content of LDPE and HDPE WV was appeared to be 12% and 8%, respectively.

Diet components can suppress inflammation and reduce cancer risk

  • Hardman, W. Elaine
    • Nutrition Research and Practice
    • /
    • 제8권3호
    • /
    • pp.233-240
    • /
    • 2014
  • Epidemiology studies indicate that diet or specific dietary components can reduce the risk for cancer, cardiovascular disease and diabetes. An underlying cause of these diseases is chronic inflammation. Dietary components that are beneficial against disease seem to have multiple mechanisms of action and many also have a common mechanism of reducing inflammation, often via the $NF{\kappa}B$ pathway. Thus, a plant based diet can contain many components that reduce inflammation and can reduce the risk for developing all three of these chronic diseases. We summarize dietary components that have been shown to reduce cancer risk and two studies that show that dietary walnut can reduce cancer growth and development. Part of the mechanism for the anticancer benefit of walnut was by suppressing the activation of $NF{\kappa}B$. In this brief review, we focus on reduction of cancer risk by dietary components and the relationship to suppression of inflammation. However, it should be remembered that most dietary components have multiple beneficial mechanisms of action that can be additive and that suppression of chronic inflammation should reduce the risk for all three chronic diseases.

간호교육 - Iowa 주에서 열린 (The Iowa Debate)

  • 대한간호협회
    • 대한간호
    • /
    • 제6권6호통권32호
    • /
    • pp.30-48
    • /
    • 1967
  • 최근 Iowa주 간호협회, 제2지구 주최로 Iowa 주 Marshall town 에서 개최된 토론회기사가 우리에게 좋은 참고재료가 될 것같아 여기 옮기기로 했다. 이 토론회에는 간호원을 위시하여 병원행정관, 학생 및 기타 간호사업에 관심을 가진 인사들 약 500명이 참석하였었다. 왜 이 많은 사람들이 이 문제에 흥미를 가지고, 토론회를 열게끔 되고 참석하게끔 되었는가 하는 의문에 대한 해답을 원문의 편집자는 아래와 같이 풀이하고 있다. 즉 ''간호교육에 대한 깊은 관심과 나아가서는 간호사업이 당면한 딜렘마에 대한 절실한 관심 때문이다''라고. 이 문제 토론을 이끌어 주신 분은 Iowa주에 있는 Iowa주립대학교 간호대학 학장이시며 저명한 간호교육자이신 Laura C. Dustan 여사와 New York의 Albany Medical Center 의무부총장인 Thomas Hale 박사의 두분인데 Hale박사는 병원 부속 간호학교제도를 제창하는 분이다. 여기 위 두분의 연설문과 연설 후에 있었던 방청객과의 질의 및 토론의 발체문을 제한된 지면 관계로 일부만 실리겠다.

  • PDF

압광 재료를 이용한 구조용 Y-TZP 소재의 고속 파괴현상 가시화 연구 (Visualization of High Speed fracture Behavior in Y-TZP by using Mechano-luminescence)

  • 김지식;손기선
    • 소성∙가공
    • /
    • 제16권5호통권95호
    • /
    • pp.348-353
    • /
    • 2007
  • The propagation of a macro-scale crack and the accompanying transformation zone around it was visualized in an Y-TZP ceramic using a mechano-luminescence (ML) technique. The technique allows realistic fractures that take place catastrophically in actual applications to be realistically stimulated. Unlike conventional quasi-static R-curves, the ML technique on a relatively fast time frame permitted a so-called quasi-dynamic R-curve in the crack speed range from 50 to 140 m/sec. to be measured. Effective toughening then commenced and the applied stress intensity factor increased to 27 $MPa{\sqrt{m}}$. The transformation zone height obtained from the ML observations was in good agreement with that predicted by the Marshall model, and coincided with previously observed results for quasi-static conditions by Raman spectorscopy and x-ray analysis.

Load deformation characteristics of shallow suspension footbridge with reverse profiled pre-tensioned cables

  • Huang, Ming-Hui;Thambiratnam, David P.;Perera, Nimal J.
    • Structural Engineering and Mechanics
    • /
    • 제21권4호
    • /
    • pp.375-392
    • /
    • 2005
  • Cable supported structures offer an elegant and economical solution for bridging over long spans with resultant low material content and ease of construction. In this paper, a model of shallow cable supported footbridge with reverse profiled pre-tensioned cables is treated and its load deformation characteristics under different quasi-static loads are investigated. Effects of important parameters such as cable sag and pre-tension are also studied. Numerical results performed on a 3D model show that structural stiffness of this bridge (model) depends not only on the cable sag and cross sectional areas of the cables, but also on the pre-tension in the reverse profiled cables. The tension in the top supporting cables can be adjusted to a high level by the pre-tension in the reverse profiled bottom cables, with the total horizontal force in the bridge structure remaining reasonably constant. It is also evident that pre-tensioned horizontally profiled cables can greatly increase the lateral horizontal stiffness and suppress the lateral horizontal deflection induced by eccentric vertical loads.

DETECTION OF X-RAY EMISSION FROM GALAXIES INSIDE AND TOWARDS THE NEARBY VOIDS

  • KIM CHULHEE;BOLLER TH.;GHOSH KAJAL K.
    • 천문학회지
    • /
    • 제38권1호
    • /
    • pp.1-6
    • /
    • 2005
  • We searched for X-ray emission from the 665 galaxies inside and towards the nearby voids by analyzing the ROSAT All-Sky Survey (RASS) data as well as the ROSAT pointed observations (PSPC). As a result we have detected six X-ray emitting galaxies. Two (UGC 10205 and NGC 7509) are in the high density region in the local void, three (UGC 749, MCG +11-10-073, and Mrk 464) are towards the nearby voids, and UGC 32 is located in the low density region. We carried out a timing analysis for both Mrk 464 and UGC 32, and a spectral analysis for Mrk 464. The light curve of Mrk 464 shows the possibility of periodic X-ray flux variation and UGC 32 shows weak, but rapid variation.