• 제목/요약/키워드: Consolidation analysis

검색결과 629건 처리시간 0.023초

극저온 기계화학적 밀링(Mechano-Chemical Milling)에 의해 제조된 ODS Fe 합금의 기계적 특성 (Mechanical Properties of ODS Fe Alloys Produced by Mechano-Chemical Cryogenic Milling)

  • 한성인;홍영환;황승준
    • 열처리공학회지
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    • 제25권3호
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    • pp.138-145
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    • 2012
  • An ${\alpha}$-Ferrite (Fe) powder dispersed with 4 vol.% of $Al_2O_3$ was successfully produced by a simple miling at 210 K with a mixture of $Fe_2O_3$, Fe and Al ingredient powders, followed by 2 step high temperature consolidation: Hot Pressing (HP) at 1323 K and then Hot Isostatic Pressing at 1423 K. The microstructure of the consolidated material was characterized by standard metallographic techniques such as XRD (X-ray Diffraction), TEM and STEM-EDS. The results of STEM-EDS analysis showed that the HIPed materials comprised a mixture of pure Fe matrix with a grain size of ~20 nm and $Al_2O_3$ with a bimodal size distribution of extremely fine (~5 nm) and medium size dispersoids (~20 nm). The mechanical properties of the consolidated materials were characterized by compressive test and micro Vickers hardness test at room temperature. The results showed that the yield strength of the ODS (Oxide Dispersion Strengthened) Fe alloy are as much as $674{\pm}39$ MPa and the improvement of the yield strength is attributed to the presence of the fine $Al_2O_3$ dispersoid.

호안에 설치한 근고사석의 안정성에 관한 연구 (A Study on Stability of Root Fixing Stone Construction in Breakwater)

  • 박춘식;김태균;서효식
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 춘계 학술발표회
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    • pp.702-706
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    • 2009
  • 유한요소해석결과를 이용하여 근고사석 시공 필요성에 대해 연구한 결과 다음과 같은 결론을 얻었다. 1. 피복석 하중에 의한 압밀침하량은 작은 양이므로 근고사석에 의한 피복석 침하 저감 효과는 없는 것으로 판단된다. 2. 융기토 제거 유무가 침하에 미치는 영향은 없는 것으로 판단된다. 3. 근고사석에 의한 침하 저감 효과는 거의 없는 것으로 해석되었으나 세굴 방지 효과는 있을 것으로 예상되므로 태풍의 영향을 직접적으로 받는 구간은 근고사석을 설치하는 것이 장기적인 안정을 위해서 바람직할 것으로 판단된다.

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연약 지반 지역의 항만 시공 단계에 따른 케이슨 변위 거동 (Sequential movement of the caisson on soft clays in the construction of the port)

  • 추윤식;정영훈;황세환;정충기
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 춘계 학술발표회
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    • pp.199-209
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    • 2009
  • The movement of the caisson used to construct a wharf front can affect functional performance of the port. Sequential movement of caissons at each stage of the construction is essential in the overall design as well as the stability of the port. It is common that back-analysis using the previous measurement is performed to predict the caisson movement, while there is no intensive study on sequential movement of the caissons according to the construction stage. In the study, we analyzed the pattern of the movement of caissons as a port is constructed. To simulate the construction of the port, the finite element method (FEM) is employed. The computed result shows that the caisson moves differently at each construction stage. When the caisson is being installed, the displacement of the caisson takes place mainly in vertical direction. In next stage of filling rocks behind the caisson, the top of the caisson move toward shore, while the bottom moves toward sea, thus rotating the caisson. The maximum rotation of the caisson takes place in the stage of filling rocks behind the caisson.

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경부고속철도 토공부에 대한 변형상태 계측 및 분석 (Measurements and Analysis of Deformation States in Roadbed in Gyeongbu High Speed Railway)

  • 진남희;김남혁;심현우
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2009년도 춘계학술대회 논문집
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    • pp.1542-1549
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    • 2009
  • The function of subgrade in the railway is to support track load on the subgrade as well as train load. Unlike the traditional railway, the uppermost subgrade layer in the Gyeongbu high speed railway was constructed as the reinforced road bed. The reinforced road bed comprises sub-ballast in the upper part and grade ballast in the lower part. The filling material such as soil and rocks in the subgrade can be settled by consolidation of original ground, compression due to self weight, plastic displacement due to train operation, and unequal settlement due to embankment material or improper compaction, therefore many efforts have been given for sufficient compaction and use of proper filling materials in the construction stage. The purpose of this study is to investigate the deformation state of subgrade in the Gyeongbu high speed railway. The investigation on the subgrade settlement was performed by choosing representative sections suspected to be settled based on the previous GPR test results and track maintenance history, measuring the settlement for some time period after installing settlement measuring instruments on and under the reinforced road bed. and analyzing the long-term subgrade settlement data from monitoring system which was installed at the construction stage of the high speed railway.

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스타일 형성에 관한 연구 - Iris Van Herpen의 스타일을 중심으로 - (A Study on the Formation of a Style - Focusing on the Style of Iris Van Herpen -)

  • 김영선
    • 패션비즈니스
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    • 제16권2호
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    • pp.124-137
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    • 2012
  • This study aims to identify the meaning and formation cause of a style, and the essential elements of style formation, through psychobiological research as well as an analysis of the designs of Iris Van Herpen, a fashion designer, who in just 6 years has developed into a world-renowned new designer. As a result, it has been found that the psychobiological causes to form a style stem from the action of 'long-term memory', which is consolidated by 'selective attention', 'perceptional subjectivity', the principle of the 'neuron's connection specificity and invariance', and the principle of a 'neuronal signal's unilateral flow'. With such action, Herpen could develop her own original composition techniques. The formative shapes created by such composition techniques are characterized by enumeration, superposition, and hanging. The study has also found that the essential elements for a designer to be able to form his/her own style include 'aesthetic originality' in which the designer views the property of a thing from his/her inherent perspective, and finds the uniqueness from the thing that only he/she can express, 'technical differences' that are creative and original, and 'formative specificity' that is summarized into one property through an impressive shape.

Rhinovirus Associated Severe Respiratory Failure in Immunocompetent Adult Patient

  • Kim, Kiwook;Song, Yeon Han;Park, Joo-Hyun;Park, Hye Kyeong;Kim, Su Young;Jung, Hun;Lee, Sung-Soon;Koo, Hyeon-Kyoung
    • Tuberculosis and Respiratory Diseases
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    • 제77권3호
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    • pp.132-135
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    • 2014
  • Rhinovirus infection is typically associated with the common cold and has rarely been reported as a cause of severe pneumonia in immunocompetent adults. A 55-year-old previous healthy woman, who consumed half a bottle of alcohol daily, presented with respiratory failure after one week of upper respiratory infection symptoms. Radiography revealed bilateral, diffuse ground glass opacity with patchy consolidation in the whole lung field; bronchoalveolar lavage fluid analysis indicated that rhinovirus was the causative organism. After five days of conservative support, the symptoms and radiographic findings began to improve. We report this rare case of rhinovirus pneumonia in an otherwise healthy host along with a review of references.

부산신항 연약지반에 적용된 PBD공법의 지반개량 시공사례 (A Case Study on the Improvements of Soft Ground Using PBD Method in Pusan New Port)

  • 손진현;김지용;변기준;이병길;유승경;김태형
    • 한국지반신소재학회논문집
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    • 제5권4호
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    • pp.1-10
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    • 2006
  • 본 논문에서는 부산신항 민자부두 북컨테이너 1-1단계 조성부지에 시공된 PBD공법의 지반개량효과를 검증하기 위하여 침하량과 압밀침하에 따른 비배수 전단강도를 비교하였다. 적용된 PBD 설계이론을 제시하였으며 CPT 시험결과와 현장 계측결과를 비교함으로써 PBD공법의 개량효과를 검토하였다. 본 사례를 통하여 향후 수행될 각종 연약지반 개량공사에 PBD 공법이 적용될 때 공법의 효용성 및 설계 해석기법의 적용성 검토에 유용한 자료가 되길 기대한다.

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Risk Allocation of Private Port Development with Hierarchical Fuzzy Process

  • Seong, Yu-Chang;Youn, Myung-Ou
    • 한국항해항만학회지
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    • 제31권4호
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    • pp.317-323
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    • 2007
  • As economic trade between Korea and China has been encouraged with the rapid growth of Chinese economy and port competition in Northeast Asia, Korean government is trying to promote development and consolidation of ports to cope with the lack of facilities. Thus, many projects for port development have been propelled including the enactment the 'Private investment promotion law for social overhead capital 1994.' However, there are still some unsettled issues since considerable part of risk is still allocated to the Government when it has to support the private businesses in these port investments whenever unexpected problems arise. Allocation of risk among the participants - in this case especially - is a very subtle issue, however, it was revealed that not many precedent researches were done on the subject. In my previous research, I classified and analyzed 4 principle risks i.e, construction, management, financial and social risk. This research investigates the reasonable allocation of the risks among the participants using the Hierarchial Fuzzy Process. In the result of analysis, responsibility of private party is the most important and it must put the responsibility before Government' roll concerned. Also, this research displayed and proposed the direction of management method on port development in a view of minimizing risk and maximizing initiative of a private party.

사이버보안 클러스터 구축 연구 (Research on the Cyber Security Cluster)

  • 박대우
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2016년도 추계학술대회
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    • pp.355-357
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    • 2016
  • 국내 정보보호 산업 성장률(7.1%)은 이전 3년 성장률(15%)에 비해 하락하였다. 정부는 K-ICT 시큐리티 2020을 발표했다. 정보보호산업의 경쟁력 강화와 창업활성화, 일자리 창출을 추진한다는 정책에 맞춰, ICT 산업과 연계된 사이버보안 클러스터 조성이 필요하다. 본 논문에서는 사이버보안 클러스터 구축을 위한 연구를 한다. 해외의 성공적인 사이버 클러스트를 조사하고 분석한다. 또한 국내에 있는 기존의 클러스트를 분석하고 문제점을 파악한다. 결론적으로 사이버 클러스트를 구축하고 운영하기 위한 방안에 대한 연구와 사이버 클러스트의 기대효과를 연구한다.

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Co-infection of Toxoplasma gondii and porcine reproductive and respiratory syndrome virus in suckling piglets in Jeju, Korea

  • Choi, Young-Min;Yang, Hyoung-Seok;Kim, Jae-Hoon
    • 한국동물위생학회지
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    • 제43권4호
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    • pp.251-256
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    • 2020
  • Two suckling piglets, 4 days and 10 days of age, showed lethargy and dyspnea after birth and mortality had been increased after incoming gilts from breeding farm. At necropsy, the lungs showed diffuse fail to collapse with rubbery consistency, edematous dilatation of interlobular septa, and lobular consolidation with purple red color. Heart was diffuse pale in color and had several irregular linear-shaped macules or patches. Histopathologically, diffuse interstitial pneumonia with the proliferation of type II pneumocytes was present in the lungs of 2 piglets. Alveolar lumens contained necrotic cellular debris derived from neutrophils and macrophages. Multifocal hemorrhage and necrotizing pneumonia with protozoan tachyzoites were observed in the lungs. Severe multifocal to confluent necrotic myocarditis, necrotic encephalitis, and necrotic adrenalitis with intralesional protozoan tachyzoites were observed in piglets. According to immunohistochemical analysis (IHC), Toxoplasma (T.) gondii tachyzoites antigens were confirmed in lung, heart, brain, and adrenal gland. And porcine reproductive and respiratory syndrome virus (PRRSV) antigens were also detected in the cytoplasm of macrophages in lungs using IHC. Based on the gross, histopathologic and immunohistochemical features, two suckling piglets were diagnosed as co-infection of T. gondii and PRRSV.