• Title/Summary/Keyword: direct differentiation

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Design Sensitivity Analysis of the Second Order Perturbed Eigenproblems for Random Structural System (불확정 구조계 고유치에 관한 이차 민감도 해석)

  • 임오강;이병우
    • Computational Structural Engineering
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    • v.7 no.3
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    • pp.115-122
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    • 1994
  • Design sensitivity analysis of the second order perturbed eigenproblems for random structural system is presented. Dynamic response of random system including uncertainties for the design variable is calculated with the first order and second order perturbation method to original governing equation. In optimal design methods, there is fundamental requirement for design gradients. A method for calculating the sensitivity coefficients is developed using the direct differentiation method for the governing equation and first order and second order perturbed equation.

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An efficient Galerkin meshfree analysis of shear deformable cylindrical panels

  • Wang, Dongdong;Wu, Youcai
    • Interaction and multiscale mechanics
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    • v.1 no.3
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    • pp.339-355
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    • 2008
  • A Galerkin meshfree method is presented for analyzing shear deformable cylindrical panels. Based upon the analogy between the cylindrical panel and the curved beam a pure bending mode for cylindrical panel is rationally constructed. The meshfree approximation employed herein is characterized by an enhanced moving least square or reproducing kernel basis function that can exactly represent the pure bending mode and thus meets the requirement of Kirchhoff mode reproducing condition. The variational form is discretized using the efficient stabilized conforming nodal integration with a smoothed nodal gradient based curvature. The resulting meshfree formulation satisfies the integration constraint for bending exactness. Moreover, it is shown here that the smoothed gradient preserves several desired properties which are valid for the standard gradient obtained by direct differentiation, such as partition of nullity and reproduction of a constant strain field. The efficacy of the proposed approach is demonstrated by two benchmark cylindrical panel examples.

Identification of a Fusion-associated Protein in the Skeletal Myoblast Using Monoclonal Antibody (단일클론항체를 이용한 배양 계배 근원세포의 융합과 연관된 단백질의 확인)

  • Kim, Chons-Rak;Won
    • The Korean Journal of Zoology
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    • v.35 no.1
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    • pp.29-36
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    • 1992
  • The present study describes the production of monoclonal antibodies against cultured chick myoblast to pursue critical proteins in muscle cell fusion. Among a panel of monoclonal antibodies, three, Mll-3H 13, Mll-3Hl8 and Mll-3H35 were inhibited movblast fusion. A single 101-kDa antigen reactive with monoclonal antibody Mll-3H35 was detected by radioimmu-noprecipitation or by immunoblotting. During the course of myogenesis, the level of the protein remarkably decreased as the cells there differentiated. These results suggest that the protein platys a direct role in the process of myoblast fusion mechanism.

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Roles of Endoplasmic Reticulum Stress in Immune Responses

  • So, Jae-Seon
    • Molecules and Cells
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    • v.41 no.8
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    • pp.705-716
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    • 2018
  • The endoplasmic reticulum (ER) is a critical organelle for protein synthesis, folding and modification, and lipid synthesis and calcium storage. Dysregulation of ER functions leads to the accumulation of misfolded- or unfolded-protein in the ER lumen, and this triggers the unfolded protein response (UPR), which restores ER homeostasis. The UPR is characterized by three distinct downstream signaling pathways that promote cell survival or apoptosis depending on the stressor, the intensity and duration of ER stress, and the cell type. Mammalian cells express the UPR transducers IRE1, PERK, and ATF6, which control transcriptional and translational responses to ER stress. Direct links between ER stress and immune responses are also evident, but the mechanisms by which UPR signaling cascades are coordinated with immunity remain unclear. This review discusses recent investigations of the roles of ER stress in immune responses that lead to differentiation, maturation, and cytokine expression in immune cells. Further understanding of how ER stress contributes to the pathogenesis of immune disorders will facilitate the development of novel therapies that target UPR pathways.

A Value-Based Real Time Pricing Under Imperfect Information on Consumer Behavior

  • Kim, Bal-Ho H.
    • Journal of Electrical Engineering and Technology
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    • v.4 no.1
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    • pp.49-54
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    • 2009
  • One of the major challenges confronting a multiservice electric utility is the establishment of the right prices for its services. The key objectives of particular pricing schemes are reasonableness of company earnings, economic efficiency, the responsiveness of supply and of the allocation of sources to the desires of consumers, and maintenance of some degree of competition. This paper proposes a value-based pricing mechanism amenable to the current deregulation situation in electricity market allowing service differentiation. The proposed pricing mechanism can be implemented in a nodal auction model, and can also be applied to direct load control.

A Second-Order Design Sensitivity-Assisted Monte Carlo Simulation Method for Reliability Evaluation of the Electromagnetic Devices

  • Ren, Ziyan;Koh, Chang-Seop
    • Journal of Electrical Engineering and Technology
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    • v.8 no.4
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    • pp.780-786
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    • 2013
  • In the reliability-based design optimization of electromagnetic devices, the accurate and efficient reliability assessment method is very essential. The first-order sensitivity-assisted Monte Carlo Simulation is proposed in the former research. In order to improve its accuracy for wide application, in this paper, the second-order sensitivity analysis is presented by using the hybrid direct differentiation-adjoint variable method incorporated with the finite element method. By combining the second-order sensitivity with the Monte Carlo Simulation method, the second-order sensitivity-assisted Monte Carlo Simulation algorithm is proposed to implement reliability calculation. Through application to one superconductor magnetic energy storage system, its accuracy is validated by comparing calculation results with other methods.

Finite element response sensitivity analysis of continuous steel-concrete composite girders

  • Zona, Alessandro;Barbato, Michele;Conte, Joel P.
    • Steel and Composite Structures
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    • v.6 no.3
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    • pp.183-202
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    • 2006
  • The behavior of steel-concrete composite beams is strongly influenced by the type of shear connection between the steel beam and the concrete slab. For accurate analytical predictions, the structural model must account for the interlayer slip between these two components. This paper focuses on a procedure for response sensitivity analysis using state-of-the-art finite elements for composite beams with deformable shear connection. Monotonic and cyclic loading cases are considered. Realistic cyclic uniaxial constitutive laws are adopted for the steel and concrete materials as well as for the shear connection. The finite element response sensitivity analysis is performed according to the Direct Differentiation Method (DDM); its analytical derivation and computer implementation are validated through Forward Finite Difference (FFD) analysis. Sensitivity analysis results are used to gain insight into the effect and relative importance of the various material parameters in regards to the nonlinear monotonic and cyclic response of continuous composite beams, which are commonly used in bridge construction.

Analysis of Types for Emotional Design Elements Favored by Galaxy Phone

  • Lee, Youngju;Kong, Jinyell
    • Journal of Communication Design
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    • v.39
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    • pp.82-90
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    • 2012
  • The present study is focused on investigating the subjective viewpoint of users favoring Galaxy phones as an element for emotional experience designs, and Q methodology used for the study of subjectivity has revealed 3 types. The first type is a type pursuing reasoned actions with high expectations for the emotional quality through direct and indirect experiences of Galaxy phones. They were shown to place an emphasis on portability and usability while having a low preference for the shape of external forms and materials. The second type is a type pursuing planned actions with an emphasis on individual subjective perceptions as well as both of physical sensation and usability. They were distinguished as a type preferring pleasure and efficiency experienced by its use. The third type is a type pursuing differentiated personalities with an emphasis on messages they want to deliver to other people through the products owned by an individual. They were identified as a type emphasizing display of personalities through differentiation in aesthetic elements.

A Study on the Architectural Application of Biological Patterns (생물학적 패턴의 건축적 적용에 관한 연구)

  • Kim, Won Gaff
    • Korean Institute of Interior Design Journal
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    • v.21 no.2
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    • pp.35-45
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    • 2012
  • The development of digital media made the change of architectural paradigm from tectonic to the surface and pattern. This means the transition to the new kind of materiality and the resurrection of ornament. This study started as an aim to apply biological pattern to architectural design from the new perception of pattern. Architectural patterns in the early era appeared as ladders, steps, chains, trees, vortices. But since 21st century, we can find patterns in nature like atoms and molecular structures, fluid forms of dynamics and new geometrical pattern like fractal and first of all biological patterns like viruses and micro-organisms, Voronoi cells, DNA structure, rhizomes and various hybrids and permutations of these. Pattern became one of the most important elements and themes of contemporary architecture through the change of materiality and resurrection of ornament with the new perception of surface in architecture. One of the patterns that give new creative availability to the architectural design is biological pattern which is self-organized as an optimum form through interaction with environment. Biological patterns emerge mostly as self-replicating patterns through morphogenesis, certain geometrical patterns(in particular triangles, pentagons, hexagons and spirals). The architectural application methods of biological patterns are direct figural pattern of organism, circle pattern, polygon pattern, energy-material control pattern, differentiation pattern, parametric pattern, growth principle pattern, evolutionary ecologic pattern. These patterns can be utilized as practical architectural patterns through the use of computer programs as morphogenetic programs like L-system, MoSS program and genetic algorithm programs like Grasshoper, Generative Components with the help of computing technology like mapping and scripting.

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Prediction Modeling on Family Life Satisfaction of Old Adults Living at Home (재가노인의 가족생활 만족도 예측모형)

  • Huh, Young Mi;Sok, Sohyune
    • Journal of Korean Academy of Nursing
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    • v.48 no.5
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    • pp.534-544
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    • 2018
  • Purpose: This study was conducted to construct and test a structural model on family life satisfaction of aged individuals living at home. The conceptual model was based on Bandura's self-efficacy and social cognitive theories (1977; 1986) and Bowen's (1976) family systems theory. Methods: From January 25 to March 5, 2016, 227 older adults living at home completed a structured questionnaire. Data were analyzed to calculate the direct and indirect effects of factors affecting family life satisfaction. SPSS WIN 20.0 and AMOS 20.0 were used. Results: The hypothetical model was a good fit for the data. The model fit indices were ${\chi}^2=78.05$, ${\chi}^2/df=1.35$, RMSR=.02, GFI=.98, AGFI=.96, NFI=.94, CFI=.98, and RMSEA=.05. Family life satisfaction was positively affected by perceived collective family efficacy, status of physical health, family communication, and family support. Depression resulted in a significant negative effect. Family differentiation had a significant indirect effect on family life satisfaction. The model explained 76% of variance in family life satisfaction. Conclusion: Perceived collective family efficacy, status of physical health, depression, family differentiation, family communication, and family support were significant factors explaining family life satisfaction among older adults staying at home. Further research should be conducted to seek intervention strategies to improve family life satisfaction among older adults living at home by focusing on the respective contributing factors.