• Title/Summary/Keyword: A property of matter

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

  • Kim, Se-Hwan;Kim, Sang-Heon;Seo, Chee-Ho
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.05a
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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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Improvement of Selection System of Waterproofing Methods for Concrete Structure (지하 콘크리트 구조물의 적정 방수공법 선정을 위한 평가시스템 제안에 관한 연구)

  • Oh, Sang-Keun;Kwak, Kyu-Sung;Choi, Sung-Min;Kwon, Shi-Won
    • Journal of the Korea Institute of Building Construction
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    • v.7 no.1 s.23
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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.

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

  • Ryu, Oh-Hyeon;Paik, Seoung-Hey;Kim, Dong-Uk
    • Journal of the Korean Chemical Society
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    • v.48 no.1
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    • pp.53-65
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    • 2004
  • This study aimed to analyze the historical evolution of general ideas concerning the particles that represent matter properties and matter changes divided into physical change and chemical change. In the science historical viewpoint, the general ideas of the base that represent matter properties has been variously revised the 5types. The definition of the matter change have also changed the 3 types. From the analysis of the definitions in secondary school science textbooks and general chemistry textbooks, we found that a lot of confusion of eras in the contents that define the concepts. Sometimes, the definition presented in one textbook was contradictory to the definitions in other textbooks. This tendency has been sustained in the textbooks from the 4th to 7th science curriculum.

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

  • Ko, Tae-Ho;Park, Woon-Ji;Lee, Chan-Ki
    • Journal of Industrial Technology
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    • v.25 no.A
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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
    • Korean Journal of Soil Science and Fertilizer
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    • v.47 no.4
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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
    • Journal of The Korean Astronomical Society
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    • v.47 no.1
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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.

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

  • Shin, Woo Seok
    • Journal of Wetlands Research
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    • v.22 no.2
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    • pp.59-65
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    • 2020
  • The purpose of this study is to determine the origin of organic matter on sediment at Sindu-ri tidal flat. Grain size, organic matter, C/N ratio and the 13C and δ15N ratio were measured at three stations (Stn. A, B, C) of the tidal flat. As a result, the spatial variation in sediment properties showed that organic matter was related positively to the sediment mud content. Organic matters originating from marine particulate organic matter (marine POM) and fish farm particulate organic matter (fish farm POM) showed sedimentation of organic matters at Stn. A, sandy tidal flat, though terrestial plant (TP) and benthic microalgae (BMA) did at Stn.C, muddy tidal flat. Meanwhile, Stn. B, the intermediate property of Stn. A and C, was affected by marine POM and BMA. Furthermore, it was revealed that the amount and origin of organic matters in the sediments depended on spatial variation, and the factors were different from the stations. Particularly, at the Stn. C, the sediment showed high concentration of TOC in terrestrial organic matter and smaller size particles (< 63 ㎛). These facts suggest the many small size particles and organic matter will affect the sediment environmental condition in the Stn. C.

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

  • Eom, Doo-Sung;Hong, Jung-Ki;Kim, Sa-Dug;Kang, Dai-Il;Lee, Myong-Hee
    • 보존과학연구
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    • s.21
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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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A study of relationship between Cadastre and Green Infrastructure (정부의 녹색정책에 의한 그린인프라와 지적의 상관관계 연구)

  • Lee, Hyun-Sook;Tcha, Dek-Kie;Lee, Jong-Min
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2010.04a
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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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A Study on the Activation of the Technology Trade to Changing Trade Environment - Focusing on the Intellectual Property Rights - (통상환경 변화에 따른 기술무역 활성화 방안 - 지식재산권을 중심으로 -)

  • Seo, Gab-Sung;Kim, Jong-Sung
    • International Commerce and Information Review
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    • v.10 no.2
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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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