• 제목/요약/키워드: A property of matter

검색결과 232건 처리시간 0.041초

코팅 경량골재를 활용한 경량골재 콘크리트의 물리적 특성 연구 (Study on Mechanical property of lightweight aggregate concrete with coated-lightweight aggregate)

  • 김세환;김상헌;서치호
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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    • pp.87-88
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    • 2011
  • High absorptance of lightweight aggregate make a hard product, work, quality management ect. for making low absorptance property, lightweight aggregate is coated by an organic matter and that way remarkably showed to decrease the absorptance by pre-study. but first, we would need a check to fit into the concrete which both fresh concrete and hardened concrete. In this study, mechanical property change of coated lightweight aggregate concrete was analysed by compared experiment with coated lightweight aggregate concrete and non-coated aggregate concrete.

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지하 콘크리트 구조물의 적정 방수공법 선정을 위한 평가시스템 제안에 관한 연구 (Improvement of Selection System of Waterproofing Methods for Concrete Structure)

  • 오상근;곽규성;최성민;권시원
    • 한국건축시공학회지
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    • 제7권1호
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    • pp.99-106
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    • 2007
  • Water leakage could be caused deterioration of environmental conditions, user condition, reduction of life span and long term safety in underground concrete structure. Many materials and construction method to repair on these problems have been developed, however, it is not proper to successful repair or raise problem of increasing repair cost However, there are many limitations as practical appraisal methods due to different view of reliability for test methods. Because, it was not enough that the technical objectivity could be lack and also application of environmental condition is inadequate. In this paper, we suggest varied test methods divided to appraisal for property of matter, construction, manufacturing, specification and maintenance, friendly environmental condition. It could be more practical as a objective standard considering various angles. In summery, it should be subdivided and differentiated to accomplish proper application and to select proper materials and construction method for repair even if the synthetical condition is very complicated.

교과서에 제시된 물질의 성질을 나타내는 기본 단위에 대한 개념과 물질변화에 대한 개념 분석 (The Analysis of Concepts Related to Basic Unit of Matter Properties and Matter Change in Science Textbooks)

  • 류오현;백성혜;김동욱
    • 대한화학회지
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    • 제48권1호
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    • pp.53-65
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    • 2004
  • 이 연구에서는 물질의 성질을 나타내는 기본 단위 중 분자에 대한 개념과 물리변화와 화학변화로 대변되는 물질변화 개념의 변천을 과학사적으로 고찰하여 특징적인 관점의 변화에 따라 구분하였다. 이 연구에서는 물질의 성질을 나타내는 기본 단위를 과학사적 변천에 따라 5가지 관점으로 유목화하였다. 그리고 물리변화와 화학변화의 정의는 물질의 성질을 나타내는 기본 단위의 개념과 밀접한 관련성을 가지는 3가지 관점으로 유목화하였다. 중학교 과학 교과서와 고등학교 화학 교과서, 그리고 대학교 일반화학 교과서에 제시된 개념을 분석한 결과, 분자의 정의와 물질 변화의 정의 안에는 이러한 여러 시대의 정의들이 혼재된 상태로 제시되어 있음을 확인할 수 있었다. 경우에 따라서는 진술 자체에 논리적 모순점이 있는 경우도 있었다. 이러한 경향은 제 4차 과학 교육과정에서부터 제 7차 과학 교육과정까지의 과학 교과서에서 지속되었다.

유동상 Media를 이용한 기존하수처리장의 Retrofitting 가능성 평가 (Evaluation on the Possibility of a Retrofitting Treatment Using Moving Media of Existing Wastewater Treatment)

  • 고태호;박운지;이찬기
    • 산업기술연구
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    • 제25권A호
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    • pp.133-139
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    • 2005
  • In this study, as MBBR(Moving Bed Biofilm Reactor) process using waste tire media is suggested for retrofitting with advanced wastewater treatment and the removal property of organic matter and nutrient and the capacity of media are evaluated through long-term operation with pilot plant following seasons, the application capacity of retrofitting with MBBR process to a existing wastewater treatment is studied. As a result of the long-term operation of the process, it is proved that there is no loss and abrasion of media, and also that it is possible to secure the sufficient attached bio-mass. The values of organic matter and nutrient in effluent are suitable for the strict discharged water quality standards in every season including winter.

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Relationship between Chemical Property and Microbial Activity of Reclaimed Tidal Lands at Western Coast Area in Korea

  • Ko, Eun-Seong;Joung, Ji-An;Kim, Chang-Hwan;Lee, Su Hwan;Sa, Tongmin;Choi, Joon-Ho
    • 한국토양비료학회지
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    • 제47권4호
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    • pp.254-261
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    • 2014
  • The scientific information between microbial activities and chemical properties of reclaimed tidal soil is not enough to apply for reclamation projects. This study was conducted to investigate the relation between chemical properties and microbial activities of reclaimed tidal lands located at western coastal area (25 samples from Nampo, Ewon, Sukmoon and Shihwa sites). Most of the reclaimed soils showed chemical characteristics as salinity soil except Nampo site. The major component influenced the salinity of reclaimed soil was identified as a sodium from the relationship between EC and exchangeable cation. With an increase in EC of soil, the population of mesophilic bacteria decreases whereas halotolerant and halophilic bacteria increases. The population of mesophilic bacteria increased with an increase in both organic matter and dehydrogenase activity. However, the population of halotolerant and halophilic bacteria decreased with an increase in organic matter. Based on the relation between chemical property and microbial activity of reclaimed tidal soil, electrical conductivity and organic matter as chemical properties of soil, population of mesophilic bacteria, halotolerant and halophilic bacteria and dehydrogenase activity as microbial activities could be the major parameters for reclamation process.

POLARIZATION AND POLARIMETRY: A REVIEW

  • Trippe, Sascha
    • 천문학회지
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    • 제47권1호
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    • pp.15-39
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    • 2014
  • Polarization is a basic property of light and is fundamentally linked to the internal geometry of a source of radiation. Polarimetry complements photometric, spectroscopic, and imaging analyses of sources of radiation and has made possible multiple astrophysical discoveries. In this article I review (i) the physical basics of polarization: electromagnetic waves, photons, and parameterizations; (ii) astrophysical sources of polarization: scattering, synchrotron radiation, active media, and the Zeeman, Goldreich-Kylafis, and Hanle effects, as well as interactions between polarization and matter (like birefringence, Faraday rotation, or the Chandrasekhar-Fermi effect); (iii) observational methodology: on-sky geometry, influence of atmosphere and instrumental polarization, polarization statistics, and observational techniques for radio, optical, and $X/{\gamma}$ wavelengths; and (iv) science cases for astronomical polarimetry: solar and stellar physics, planetary system bodies, interstellar matter, astrobiology, astronomical masers, pulsars, galactic magnetic fields, gamma-ray bursts, active galactic nuclei, and cosmic microwave background radiation.

신두리 갯벌 퇴적 유기물의 기원과 특성 (The Origin and Characteristics of Sedimentary Organic Matter on Sindu-ri Tidal Flat, Korea)

  • 신우석
    • 한국습지학회지
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    • 제22권2호
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    • pp.59-65
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    • 2020
  • 본 연구의 목적은 신두리 갯벌 퇴적물의 유기물 기원을 추정하는 것이다. 이를 위해 갯벌의 3지점(Stn. A, B, C)에서 입도, 유기물 함량, C/N비 및 탄소와 질소 안정동위원소를 측정하였다. 그 결과, 퇴적물의 공간적 변화에서 유기물은 퇴적물 미립자 함량과 양의 상관관계가 있음을 보여주었다. 모래 갯벌인 지점 A에서는 해양 미립자 유기물(해양 POM)과 어류 양식장 미립자 유기물(어류 양식장 POM)에서 비롯된 유기물의 퇴적 특성을 보였고, 펄 갯벌인 지점 C에서는 육상식물(TP)과 저서미세조류(BMA)의 유기물 퇴적 특성을 보였다. 한편 혼합갯벌인 지점 B에서는 지점 A와 지점 C 중간적인 해양 POM과 저서미세조류의 영향을 받고 있었다. 또한 퇴적물 내 유기물의 양과 기원은 공간적 변화에 의존하며 그 요인은 조사지점간의 차이가 있음을 알 수 있었다. 특히, 지점 C의 퇴적물은 육상유기물과 펄 미립자(< 63 ㎛)로 높은 TOC 농도를 보였다. 이러한 사실은 미립자 함량과 유기물질이 지점 C의 퇴적환경 조건에 영향을 미치는 것으로 사료된다.

석조문화재 받침용 쐐기 재질의 물성 실험 연구 (The study on the property of material for the shim of stone cultural properties)

  • 엄두성;홍정기;김사덕;강대일;이명희
    • 보존과학연구
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    • 통권21호
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    • pp.101-118
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    • 2000
  • Stone cultural properties(pagoda, Buddhist statue etc.) is moved in original place for many reasons and restored after taking to pieces for structural safety. With the movement and restoration after taking to pieces, the cast iron is used for the sake of a fixation and horizontality. The stone cultural properties are spoiled the beauty and accelerated the weathering because of the corrosion product of cast iron. So we need to substitute for the improved property in all aspects. We are executed the corrosion test and inquired the property of material on the usable material for the shim of stone cultural properties. That is the Cast iron, Stainless steel, Titanium and Fiber Reinforced Plastics. In the result of the physical property and strength, the Stainless steel and Titanium was superior to the Cast iron. And the Stainless steel and Titanium was slower than the Cast iron in the corrosion velocity for the acid, salt and rain. If the shim is substitute the Stainless steel or Titanium for the Cast iron, the stone cultural properties are able to reduce the pollution of stone cultural properties by corrosion product and should not happen in the matter of stone pagoda.

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정부의 녹색정책에 의한 그린인프라와 지적의 상관관계 연구 (A study of relationship between Cadastre and Green Infrastructure)

  • 이현숙;차득기;이종민
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2010년 춘계학술발표회 논문집
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    • pp.87-89
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    • 2010
  • The "Green Policy" of Korean government is classified as three categories, the first is 'reduction of fossil fuel use', the second is 'clean energy development' and the last is 'sustainable green property which has a continuous value in the use'. In this matter, this study provides how the green property concept include green infrastructure and how to link the green infrastructure to effective geo-spatial management by cadastre system. The establishment of green infrastructure is not a simple procedure, but definitely starts from the cadastre system. If the green policy includes sustainable way of land/marine use, the green cadastre is significant because of its possibilities to be used as a powerful implementation.

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통상환경 변화에 따른 기술무역 활성화 방안 - 지식재산권을 중심으로 - (A Study on the Activation of the Technology Trade to Changing Trade Environment - Focusing on the Intellectual Property Rights -)

  • 서갑성;김종성
    • 통상정보연구
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    • 제10권2호
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    • pp.165-188
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    • 2008
  • Some developed countries have already long been adapted to these changes in the international economic environment would improve productivity rather than traditional technology based on more high value-added business and increased investment. IPR protection is not just a national interest in the creation and growth of dimensions beyond the country's national competitiveness and a driving force to decide whether to challenge the core of the matter. Therefore, the importance of IPR in the country to raise awareness of IPR protection, and for systematic and comprehensive policy that will continue to be prepared.

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