• 제목/요약/키워드: fine grained

검색결과 712건 처리시간 0.027초

하이브리드 용접에 의한 세립강 용접부의 기계적 성질에 관한 연구 (Mechanical Property of Ultra Fine Grained Steel Weld by Hybrid Welding)

  • 동현우;안용식
    • 동력기계공학회지
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    • 제15권1호
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    • pp.45-50
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    • 2011
  • The effect of Mn and Ti contents in filler wire on the microstructure and mechanical property of weld metal has been investigated after hybrid welding with ultra fine grained (UFG) steel. The microstructure and distribution of alloy compositions at the top region of weld zone were quite different with those at the bottom region after hybrid welding. The bottom region of weld zone contained higher Mn and Ti contents, and consequently the hardness of bottom region was higher than that of top region. With the increase of Mn and Ti contents in filler wire, the volume percent of acicular ferrite in weld metal decreased, and the weld zone showed higher hardness and better impact property.

Classifying Articles in Chinese Wikipedia with Fine-Grained Named Entity Types

  • Zhou, Jie;Li, Bicheng;Tang, Yongwang
    • Journal of Computing Science and Engineering
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    • 제8권3호
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    • pp.137-148
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    • 2014
  • Named entity classification of Wikipedia articles is a fundamental research area that can be used to automatically build large-scale corpora of named entity recognition or to support other entity processing, such as entity linking, as auxiliary tasks. This paper describes a method of classifying named entities in Chinese Wikipedia with fine-grained types. We considered multi-faceted information in Chinese Wikipedia to construct four feature sets, designed different feature selection methods for each feature, and fused different features with a vector space using different strategies. Experimental results show that the explored feature sets and their combination can effectively improve the performance of named entity classification.

Prosodic Strengthening in Speech Production and Perception: The Current Issues

  • Cho, Tae-Hong
    • 음성과학
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    • 제14권4호
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    • pp.7-24
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    • 2007
  • This paper discusses some current issues regarding how prosodic structure is manifested in fine-grained phonetic details, how prosodically-conditioned articulatory variation is explained in terms of speech dynamics, and how such phonetic manifestation of prosodic structure may be exploited in spoken word recognition. Prosodic structure is phonetically manifested in prosodically important landmark locations such as prosodic domain-final position, domain-initial position and stressed/accented syllables. It will be discussed how each of the prosodic landmarks engenders particular phonetic patterns, ow articulatory variation in such locations are dynamically accounted for, and how prosodically-driven fine-grained phonetic detail is exploited by listeners in speech comprehension.

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다짐된 세립토의 인장강도 측정법의 개발 (Development of Tensile Strength Measurement Technique on Compacted Fine-Grained Soils)

  • 김태형;김찬기;윤중만;유승경
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
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    • pp.1538-1545
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    • 2005
  • Theoretical and experimental result studies of the unconfined penetration test (UP) method are conducted to suggest a new test method by improving the UP method for determination of the tensile strength of compacted fine-grained soils. From the theoretical aspect, the tensile strength of the specimen is estimated from the maximum load by the theory of perfect plasticity with assumptions, sufficient local deformability and modified Mohr-Coulomb failure criterion. Experimentally, some factors including relative size of specimen-disc, disc diameter, and loading rate are needed more study, because these factors significantly affect the results of tensile strength. Improvement of the alignement between two discs and specimen in the UP test is also necessary to eliminate the error due to eccentrically loading.

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Fine-Grained FSMD Power Gating Considering Power Overhead

  • Shin, Chi-Hoon;Oh, Myeong-Hoon;Sim, Jae-Woo;Jeong, Jae-Chan;Kim, Seong-Woon
    • ETRI Journal
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    • 제33권3호
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    • pp.466-469
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    • 2011
  • As a fine-grained power gating method for achieving greater power savings, our approach takes advantage of the finite state machine with a datapath (FSMD) characteristic which shows sequential idleness among subcircuits. In an FSMD-based power gating, while only an active subcircuit is expected to be turned on, more subcircuits should be activated due to the power overhead. To reduce the number of missed opportunities for power savings, we deactivated some of the turned-on subcircuits by slowing the FSMD down and predicting its behavior. Our microprocessor experiments showed that the power savings are close to the upper bound.

Fatigue Properties of Fine Grained Magnesium Alloys after Severe Plastic Deformation

  • Chung Chin-Sung;Chun Duk-Kyu;Kim Ho-Kyung
    • Journal of Mechanical Science and Technology
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    • 제19권7호
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    • pp.1441-1448
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    • 2005
  • Fine grained AZ31 and AZ61 magnesium alloys produced by equal channel angular pressing (ECAP) were tested for investigating tensile and fatigue properties, including microstructure, monotonic tensile flow, fatigue life and crack growth rate. For the two alloys, the yield stress of the ECAPed sample was lower than that of the unECAPed (=as received) sample, because of the fact that the softening effect due to texture anisotropy overwhelmed the strengthening effect due to grain refinement. Grain refinement of the AZ31 and AZ61 alloys through ECAP was found not to be significantly effective in increasing fatigue strength.

A Cellular Formation Problem Algorithm Based on Frequency of Used Machine for Cellular Manufacturing System

  • Lee, Sang-Un
    • 한국컴퓨터정보학회논문지
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    • 제21권2호
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    • pp.71-77
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    • 2016
  • There has been unknown polynomial time algorithm for cellular formation problem (CFP) that is one of the NP-hard problem. Therefore metaheuristic method has been applied this problem to obtain approximated solution. This paper shows the existence of polynomial-time heuristic algorithm in CFP. The proposed algorithm performs coarse-grained and fine-grained cell formation process. In coarse-grained cell formation process, the cell can be formed in accordance with machine frequently used that is the number of other products use same machine with special product. As a result, the machine can be assigned to most used cell. In fine-grained process, the product and machine are moved into other cell that has a improved grouping efficiency. For 35 experimental data, this heuristic algorithm performs better grouping efficiency for 12 data than best known of meta-heuristic methods.

연산 히스토리를 이용한 소프트웨어 일관성 관리 모델 (A Software Consistency Management Model using Operation History)

  • 노정규
    • 컴퓨터교육학회논문지
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    • 제5권4호
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    • pp.61-69
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    • 2002
  • 소프트웨어 문서는 논리적인 객체와 객체간의 관계로 이루어지며 개발 과정에서 여러 버전이 생성된다. 효율적인 소프트웨어 개발을 위해서는 소프트웨어 구성 요소에 변경이 일어났을 경우 변경의 내용과 변경이 전파되어야 할 범위를 쉽게 알 수 있어야 한다. 그러나 큰 단위 소프트웨어 객체 관리에서는 변경의 내용과 전파 범위를 알기 힘들다. 따라서 논리적인 객체와 객체간의 종속성을 관리하는 미세 단위 객체 관리가 필요하다. 본 논문에서는 소프트웨어 편집 과정에서 적용되는 연산 히스토리를 이용한 미세단위 소프트웨어 일관성 관리 모델을 제안하였다. 본 논문에서는 미세 단위 일관성 관리에 대한 정형적인 모델을 제시하였으며, 관성은 객체간의 종속성과 객체에 적용된 연산의 종류에 의해 관리되므로 불필요한 변경 전파를 피할 수 있다.

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초기 소성변형이 초미세 결정립 페라이트-마르텐사이트 이상조직 탄소강의 건식 미끄럼마멸 특성에 미치는 영향 (Effect of Prior Deformation on the Sliding Wear of Ultra-fine Grained Ferrite-Martensite Dual Phase Steel)

  • 박준기;이슬기;신동혁;김용석
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2008년도 춘계학술대회 논문집
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    • pp.521-524
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    • 2008
  • Effect of prior deformation on the sliding wear of the ultra-fine grained (UFG) ferrite-martensite dual phase (DP) steel was investigated. The UFG DP steel was fabricated by the ECAP and subsequent intercritical annealing. The steel was cold rolled before the wear test, and the effect of the prior deformation on the wear was examined. The wear tests were carried out at various loads against a bearing steel ball. The wear rate of the UFG DP steel that did not experience the prior deformation was higher than that of the coarse-grained (CG) DP steel, because of more severe surface shear deformation. The wear rate of the specimens with prior deformation was much higher than that of the specimen without prior deformation. The deformed CG DP specimen showed higher rate than the deformed UFG DP specimen, and the rate-variation of the CG DP steel was much bigger under the same test condition.

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Bending Strength of Textured Alumina Prepared by Slip Casting in a Strong Magnetic Field

  • Suzuki, Tohru S.;Uchikoshi, Tetsuo;Morita, Koji;Hirage, Keijiro;Sakka, Yoshio
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.1099-1100
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    • 2006
  • The mechanical properties of ceramics materials can be tailored by designing their microstructures. We have reported that development of texture can be controlled by slip casting in a strong magnetic field followed by heating even for diamagnetic ceramics such as alumina. A strong magnetic field of 12T was applied to the suspension indcuding alumina powder to rotate each particle during slip casting. The sintering was conducted at the desired temperature in air without a magnetic field. C-axis of alumina was parallel to the magnetic field. Bending strength of textured alumina depended on the direction of oriented microstructure.

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