• 제목/요약/키워드: FAC

검색결과 329건 처리시간 0.036초

Energy-based damage index for steel structures

  • Bojorquez, E.;Reyes-Salazar, A.;Teran-Gilmore, A.;Ruiz, S.E.
    • Steel and Composite Structures
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    • 제10권4호
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    • pp.331-348
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    • 2010
  • Ample research effort has been oriented into developing damage indices with the aim of estimating in a reasonable manner the consequences, in terms of structural damage and deterioration, of severe plastic cycling. Although several studies have been devoted to calibrate damage indices for steel and reinforced concrete members; currently, there is a challenge to study and calibrate the use of such indices for the practical evaluation of complex structures. The aim of this paper is to introduce an energy-based damage index for multi-degree-of-freedom steel buildings that accounts explicitly for the effects of cumulative plastic deformation demands. The model has been developed by complementing the results obtained from experimental testing of steel members with those derived from analytical studies regarding the distribution of plastic demands on several steel frames designed according to the Mexico City Building Code. It is concluded that the approach discussed herein is a promising tool for practical structural evaluation of framed structures subjected to large energy demands.

Some Physical Properties of Regeneration Cemented Carbide Using Recycling WC Fine Powder by Tin Impregnation Method

  • Nakamura, Mitsuru;Lee, Sang-Hak;Kim, Ha-Young
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.661-662
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    • 2006
  • Development of recycling method at cemented carbide scraps was researched. Some properties of recycled cemented carbides were investigated. Recycled WC fine powder suffered the surface oxidation. Therefore it was necessary to be done by reduction treatment at 1073K-3.6ks under hydrogen atmosphere. When sintering condition at 1673K-3.6ks was treated under vacuum condition, it gained the deflective strength of about 90%, and gained hardness and sintering density about same value compared with commercial alloys. As a result, it was able to recycle only by 7 processes.

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향상된 유전알고리듬과 Simplex method을 이용한 다봉성 함수의 최적화 (Optimization of Multimodal Function Using An Enhanced Genetic Algorithm and Simplex Method)

  • 김영찬;양보석
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2000년도 추계학술대회논문집
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    • pp.587-592
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    • 2000
  • The optimization method based on an enhanced genetic algorithms is proposed for multimodal function optimization in this paper. This method is consisted of two main steps. The first step is global search step using the genetic algorithm(GA) and function assurance criterion(FAC). The belonging of an population to initial solution group is decided according to the FAC. The second step is to decide the similarity between individuals, and to research the optimum solutions by simplex method in reconstructive search space. Two numerical examples are also presented in this paper to comparing with conventional methods.

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감육예측 및 수치해석 기법을 활용한 소구경 탄소강배관 감육영향 분석에 관한 연구 (Technology Based on Wall-Thinning Prediction and Numerical Analysis Techniques for Wall-Thinning Analysis of Small-Bore Carbon Steel Piping)

  • 이대영;황경모;진태은;박원;오동훈
    • 대한기계학회논문집B
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    • 제34권4호
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    • pp.429-435
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    • 2010
  • 국내를 포함한 전 세계 50여개 원전의 발전사업자는 유동가속부식에 의한 탄소강 배관 감육을 관리하기 위하여 CHECWORKS 프로그램을 이용하고 있다. CHECWORKS 프로그램은 대구경 배관에만 적용 가능한 것으로 알려져 있기 때문에 소구경 배관에 대해서는 현장 배관감육 관리 담당자의 경험과 판단에 따라 배관을 관리하고 있다. 이에 따라 본 논문에서는 국내 원전 소구경 배관 4개 라인그룹에 대하여 CHECWORKS 프로그램과 FLUENT 코드를 이용하여 유동가속부식과 유동 특성을 분석하였다. 그 결과 현장 배관감육 관리 담당자의 기술력에 따라 CHEC- WORKS 프로그램도 소구경 배관 감육 관리에 이용할 수 있는 것으로 나타났다.

Comparison of Motor Function and Skill between Stroke Patients with Cerebellar and Non-cerebellar Lesion in Sub-acute Stage

  • Kwon, Yong Hyun;Kim, Chung Sun
    • The Journal of Korean Physical Therapy
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    • 제24권6호
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    • pp.423-427
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    • 2012
  • Purpose: The cerebellum is a region of brain structure that plays an important role in calibrating two different information of neural signal from descending motor commands and from ascending sensory inputs. Damage of the cerebellum shows a variety of classic motor symptoms such as postural and locomotor dysfunctions. Therefore, we tried to investigate motor function and skill in stroke patients with cerebellar lesions in sub-acute stage, and compare with these functions of patients with non-cerebellar lesions. Methods: Total twelve stroke patients with cerebellar lesion and 130 stroke patients with non-cerebellar lesions were retrospectively recruited in this study. For evaluation of motor strength, Motricity index (MI) for upper and lower limbs was tested. For measurement of motor skill function, the modified Brunnstrom classification (MBC), Manual function test (MFT), functional ambulatory category (FAC), and Barthel index were adopted. Results: In comparison of motor strength and motor skill function between two groups, statistical differences between the two groups were significantly observed only in upper MI and FAC. Although no significant differences were found in other variables, stroke patients with cerebellar lesion had higher scores in lower and total MI, MBC, and MFT, whereas they had lower scores in FAC and Barthel index. Conclusion: Our results showed that stroke patients with cerebellar lesion had greater impact on movement functions related to hand motor and walking ability in activities of daily life, compared with patients with non-cerebellar lesion, in spite of similar degree of motor function and skill between the two different lesioned-groups.