• 제목/요약/키워드: regional materials

검색결과 1,081건 처리시간 0.026초

구조용 중탄소강 SM45C의 열처리에 따른 기계적 성질변화 (Heat treatment effect on Mechanical property in SM45C (AISI1045) steel)

  • 전상조;이임균;김송희
    • 산업기술연구
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    • 제6권
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    • pp.33-38
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    • 1986
  • The aim of this study is to find out the relationships between the microstructures of SM45C(AISI1045) steel and fatigue crack propagation behaviour. Three microstructures such as (i) as received (fully annealed). (ii) water quenched and tempered, and (iii) oil quenched and tempered were used for fundamental mechanical testing and fatigue crack proagation test. The microstructures of (ii) and (iii) showed superior in tensile strength to (i). Resistance against fatigue crack propagation was higher in structure (i), while tensile properties were better in structures (ii) and (iii). It is believed due to that the enhancement of roughness of fracture surface obsered in structure (i) increases ${\Delta}Kth$ and lowers fatigue crack growth rate. However it does not necessarily mean the quenched and tempered structures (ii) and (iii) are undesirable for the engineering component because fatigue limit in low cycle test appears usually higher in the microstructures of higher strength.

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제주건축물의 지역별 및 외피디자인 요소별 특징에 관한 기초 연구 (A Basic Research on Regional Characteristics and Design Factors of Buildings Skin in Jeju Province)

  • 김태일;양건;이성호
    • 한국실내디자인학회논문집
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    • 제20권4호
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    • pp.11-20
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    • 2011
  • Jeju Special Self-Governing Province are trying every effort to be presented as an International Free City with unique combination of history, culture and landscape, This research focuses on the analysis of characteristics we can find in buildings in Jeju province. The main purpose is to provide basic and informative materials for the landscape formation of Jeju by investigating current status of buildings in Jeju province. This research divides Jeju province into 34 areas and categorizes buildings by use. 2,973 cases in total are collected and analyzed their architectural features. A basic analysis of the collected data is conducted in the first and the second stages. And In the third stage, 505 cases whose addresses can be identified are selected for the in-depth analysis of the registered building data on architecture year, building area, and total area. These data are analyzed by the categories of region, year, and size for the study of general characteristics of buildings in Jeju. The results show that territoriality is weak because of the simplicity of building layout on the streets. Exterior form of buildings, streetscape image, and overall city image are tedious and boring because of the lack of the variety of facade and exterior finishing materials.

페터 춤토르 작품에 나타난 존재론적 공간개념에 관한 연구 (A Study on Ontological Spatial Concept shown at Works of Peter Zumthor)

  • 이옥재;김문덕
    • 한국실내디자인학회논문집
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    • 제24권2호
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    • pp.117-124
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    • 2015
  • With the modern society approaching, a lot of new paradigms have been created which can be explained by the existing space notions while suspicions on the true essence and existence of space have been raised. Ontology regards as the beginning the cause for a 'Field' which will be faced for the research of the essence of a space where 'being-in-the-world' exists. This study has analyzed the existing method of space construction in the spatial thinking and works of Peter Zumthor who mentioning ontological viewpoint as the physiological background of his works so that the ontological spatial concept may be clarified. The following is the study results. First, in order to construct the structures of his own designing into a 'Field' for experiencing the existential meaning, Zumthor chose a reductive pattern with the entire additional elements removed. The materials leading the subjects to call attention to memory and experience and the methods dealing with it enables the realization of various spatial essences. Second, the ontological event-system is required for the formation of relationship among beings. He tried to create a spatial meaning by introducing external environment into the inside and using the materials reflecting regional features and phenomenological empiricism through the multisensory experience. Third, he applied assimilation/insert/adjustment/formative change as the way of constructing the relationship between site and structure.

Life-cycle Environmental Impact Assessment of High-rise Apartments

  • Kim, Samuel;Kim, Se-Hwan;Lee, Sung
    • Architectural research
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    • 제3권1호
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    • pp.29-36
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    • 2001
  • Concern about global environment has been increasing in recent years. Efforts to minimize the environmental impact to the globe as well as human beings have increased, especially in the late twentieth century. The study researches one of the solutions for the environmentally friendly building construction, which can contribute to sustaining the world environment. Assessment and proposals are made for high-rise apartments, one of the most popular construction types nowadays in Korea. Since the volume of high-rise apartment construction is so great, a small improvement in each building will make a great contribution. Assessments are made over the life-span of apartment buildings. A tool named EIAHA (Environmental Impact Assessment for High-rise Apartment) has been made through references from western examples, mainly in the UK. The components of EIAHA include passive design strategies, building materials, energy consumption during building operation and management/maintenance. Although the issues are on a global scale, solutions are sought on regional scale. Korean high-rise apartments are assessed with the tool and suggestions for sustainable development are made mainly for improvement of embodied energy of building materials and the life of buildings.

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대학도서관 공동보존서고 건립·운영 모형 연구 - 부산·경남지역 국립대를 중심으로 - (A Study on the Establishment and Operation of the Collaborative Repository for University Libraries with a special reference to National Universities in Busan/Gyeongnam area)

  • 강은영;장덕현
    • 한국도서관정보학회지
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    • 제49권2호
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    • pp.105-129
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    • 2018
  • 최근 지역대표도서관을 중심으로 자료의 공동보존을 위한 노력이 가시화되고 있으나 이는 대체로 공공도서관을 중심으로 한 움직임이다. 이에 이 연구는 부산 경남지역을 중심으로 국립대학도서관을 위한 공동보존서고 건립 운영모형을 제안하는 것을 목적으로 하였다. 이를 위해 1) 참여도서관 보존서고의 규모와 시설, 운영정책, 장서량과 이관현황, 포화상태 등을 조사하고 이관예정자료의 규모를 추산하는 등 현황분석을 실시한 다음, 2) 건립형태, 조직과 인력, 자료이관지침, 자료정리와 배가, 자료제공 등 공동보존서고 건립 운영 모형을 제안하였다.

탄소 나노 물질의 형상에 따른 구리/탄소나노물질 하이브리드 필러의 전도성 향상 거동 분석 (Effects of Morphologies of Carbon Nanomaterials on Conductivity of Composites Containing Copper/Carbon Nanomaterial Hybrid Fillers)

  • 이연주;홍성욱;최현주
    • 한국분말재료학회지
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    • 제25권5호
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    • pp.435-440
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    • 2018
  • In the present study, we develop a conductive copper/carbon nanomaterial additive and investigate the effects of the morphologies of the carbon nanomaterials on the conductivities of composites containing the additive. The conductive additive is prepared by mechanically milling copper powder with carbon nanomaterials, namely, multi-walled carbon nanotubes (MWCNTs) and/or few-layer graphene (FLG). During the milling process, the carbon nanomaterials are partially embedded in the surfaces of the copper powder, such that electrically conductive pathways are formed when the powder is used in an epoxy-based composite. The conductivities of the composites increase with the volume of the carbon nanomaterial. For a constant volume of carbon nanomaterial, the FLG is observed to provide more conducting pathways than the MWCNTs, although the optimum conductivity is obtained when a mixture of FLG and MWCNTs is used.

증착조건에 따른 ZnO 나노와이어의 성장 및 photoluminescence 특성 (Growth and photoluminescence characteristics of ZnO nanowire depending on deposition condition)

  • 오원석;장건익
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.172-172
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    • 2008
  • By thermal evaporation method, well-aligned ZnO nanowires were synthesized on sapphire substrate at $1000^{\circ}C$ with different oxygen flow rate by using pure ZnO powder (99.999 %). The as-synthesized ZnO nanowires were characterized by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The well-aligned nanowires are single crystalline in nature and perpendicularly grown along the c-axis. Also the growth rate of nanowires, such as diameter and length, had a tendency to increase as oxygen flow rate increased. Based on the PL measurement of ZnO nanowires, we found that the near band edge of emission redshifted with the increasing intensity of the defect-related green emission in proportion to the increase of oxygen flow rate. "This research was supported by the Korea Research Foundation Grant funded by the Korean Government(MOEHRD)" (The Regional Research Universities Program/Chungbuk BIT Research-Oriented University Consortium).

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도시호텔 공용공간 실내건축의 내장재 특성에 관한 연구 - 서울시 특1급 호텔을 중심으로 - (A Study on the Characteristics of Interior Materials for the Public Area in the City Hotels - Focused on First Class Hotels in Seoul -)

  • 전유경;이창노
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2007년도 추계학술발표대회 논문집
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    • pp.149-154
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    • 2007
  • The city hotel of today lodges and, from eating and drinking putting first cultural exchange, information transmission and sports and the leisure back to be various the open community of the city which equips a composition facility as the market fixation it is being turning out. Like this regional and culture flow scope of the user fall in love, width widely try to be diffused the data about the internal organs re-analysis our country hotel plan the place where it is the actual condition where the system and diverse royal tomb city hotel plan is coming to be demanded regarding very is the actual condition which is insufficient. The research which it sees hereupon from domestic is erected in existing and the city hotel which is coming to be operated re- internal organs in the object it investigate, analyze re- internal organs and new city hotel plan hour to present a plan fundamental data and the guide regarding the internal organs re-quality of the crew-serve space interior construction it could be applied there is an objective of the research by the box sleep.

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유기농업의 경제적 배경과 경영방식에 관한 고찰 (A study on the economic background and management method in organic farming)

  • 김호
    • 한국유기농업학회지
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    • 제3권1호
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    • pp.43-70
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    • 1994
  • Presently the concept of organic farming has not simply technical categories such as no agricul-tural chemicals and no chemical fertilizer but can be also extended to the categories of economics, food nutrition, environmental and philosophical aspects. Accordingly, in order to understand cor-rectly organic farming, it is necessary to look into the concept including these extended aspects. So the production and consumption activities of organic farming products are largely based on the fundamental philosophy of organic farming. That is, all the life that is included in an ecosystem has to live in symbiosis, which is based on life circulation principle. And if this circultaion system is destroyed, human life may be threatended. Farmers who produce organic farming prducts(organic farmer) receive price higher than general farmers. This study shows the gap of 46.9% in two products. Also, since the price of organic farming products is fluctuated less relatively, Organic farming pruducts can be competed against imported agricultural products in terms of food safety. And organic farming should be managed by crop rotation and composite farm management upon which the principle of material circulation is worked. This composite management is devided into 2 classes, which are individually livestock-have-composite management and regional composite management. These management method means that organic materials are crucial to maintain the structure and fertility and these organic materials are easily obtained from animal as by-products.

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응력제거 열처리한 Mg-AZ31B 합금 TIG 용접부의 기계적 특성과 미세조직 변화에 미치는 용접조건의 영향 (The Influence of Welding Conditions on Mechanical Properties and Microstructural Change of TIG Welded Joint in Stress Relieve Heat Treated Mg-AZ31B Alloy)

  • 김용길;정동석;배차헌
    • 열처리공학회지
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    • 제17권4호
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    • pp.230-235
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    • 2004
  • Present work was carried out to investigate the influence of welded conditions, such as welding current, diameter of welding wire on the microstructural change and mechanical properties of TIG welded joint in AZ31B Mg alloy. It was found that good and sound welded joint was achieved in all welding conditions. The grain size decreased with increasing welding current and decreasing diameter of welding wire. Also, the second phases were homogeneously distributed in the grain and grain boundary as decreasing welding current and diameter of welding wire. The ${\beta}$ discontinuos precipitates were observed in the welded joint, but this microstructure has not been reported by previous researchs in AZ31B Mg alloy. The hardness value is affected by the existence state of the second phase and the hardness of the welded joint region is lower than the other regions in welded AZ31B Mg alloy. The strength of the welded joint region was influenced by the grain size and has more than 90%, compared to that of ASTM standard specification.