• Title/Summary/Keyword: structural adaptation

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Temperature on structural steelworks insulated by inorganic intumescent coating

  • Choi, J. Yoon;Choi, Sengkwan
    • Steel and Composite Structures
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    • v.15 no.1
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    • pp.1-14
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    • 2013
  • Predicting the fire resistance of structures has been significantly advanced by full scale fire tests in conjunction with improved understanding of compartmental fire. Despite the progress, application of insulation is still required to parts of structural steelwork to achieve over 60 minutes of fire rating. It is now recognised that uncertainties on insulation properties hinder adaptation of performance based designs for different types of structures. Intumescent coating has recently appeared to be one of most popular insulation types for steel structures, but its design method remains to be confirmed by empirical data, as technical difficulties on the determination of the material properties at elevated temperatures exist. These need to take into account of further physiochemical transitions such as moving boundary and endothermic reaction. The impetus for this research is to investigate the applicability of the conventional differential equation solution which examines the temperature rise on coated steel members by an inorganic intumescent coating, provided that the temperature-dependent thermal/mechanical insulation properties are experimentally defined in lab scale tests.

A STUDY ON ELASTO-PLASTIC ANALYSIS OF SPHERICAL SHELL BY RIGID ELEMENT METHOD(I) - Theoretical Consideration on Elasto-Plastic Analysis of Spherical Shell - (강체요소법에 의한 구형쉘의 탄소성해석에 관한 연구( I ) - 구형쉘의 탄소성 해석에 관한 이론적 고찰 -)

  • 권택진;한상율;서삼열;박강근
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1988.10a
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    • pp.18-23
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    • 1988
  • This study on the elasto-plastic analysis of spherical shell by rigia element method is classified into two parts : (1) theoretical consideration on elasto-plastic analysis of spherical shell, (2) elastic and elasto-plastic analysis of spherical shell with the open stiff ring. In 1982, Y. Tsuboi proposed the new analytical method which is called the rigid element method, for analyzing the elasto-plastic behavior of wall-type precast concrete structures by applying the concepts of rigid bodies-sprins model (i.e., when structures reach their ultimate state of leading, they may be yield, collapsed ana crushed into pieces, and each part or piece of structures mar move like a rigid body.). In this paper, for improvement and expansion this rigid element method, it is proposed the adaptation equation of rectangular-shaped spherical element and rectangular-shaped spherical bending element developed by present authors, and the analytical procedure for the elastic and the elasto-plastic increment method of structures.

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Immune Algorithm Based Active PID Control for Structure Systems

  • Lee, Young-Jin;Cho, Hyun-Cheol;Lee, Kwon-Soon
    • Journal of Mechanical Science and Technology
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    • v.20 no.11
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    • pp.1823-1833
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    • 2006
  • An immune algorithm is a kind of evolutional computation strategies, which is developed in the basis of a real immune mechanism in the human body. Recently, scientific or engineering applications using this scheme are remarkably increased due to its significant ability in terms of adaptation and robustness for external disturbances. Particularly, this algorithm is efficient to search optimal parameters against complicated dynamic systems with uncertainty and perturbation. In this paper, we investigate an immune algorithm embedded Proportional Integral Derivate (called I-PID) control, in which an optimal parameter vector of the controller is determined offline by using a cell-mediated immune response of the immunized mechanism. For evaluation, we apply the proposed control to mitigation of vibrations for nonlinear structural systems, cased by external environment load such as winds and earthquakes. Comparing to traditional controls under same simulation scenarios, we demonstrate the innovation control is superior especially in robustness aspect.

The Type of Composition and Classification of Tension Structure Systems in Architecture (건축 인장구조시스템의 분류와 구성유형)

  • Lee, Ju-Na;Park, Sun-Woo;Park, Chan-Soo
    • Journal of Korean Association for Spatial Structures
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    • v.3 no.3 s.9
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    • pp.111-120
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    • 2003
  • Tension members is a type of effective structural member, which is often used in large span structures. The structure systems composed with tension members are combined in various way and specific formations. So, there are need to research into the formations of tension structure and the type of adaptation in tension structure architectures. The structure systems with tension members were considered as tension main system, vector system and tension supported bending system, comprehensively. And tension structures were classified into the formation of tension structure with uniaxial or multiaxial line tension member, with surface member, with hybrid member of line and surface, concerning the flow of tension force. In each the formation of tension structure, the typical adaptations to architecture were also investigated through architecture examples. The type of the formation can be used to plan an architecture with respect to the flow of tension force and structural feature.

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An Experimental Study on Properties of Polymer Cement Concrete with a Kind of Admixtures (혼화제 종류에 따른 폴리머 시멘트 콘크리트의 특성에 관한 실험적 연구)

  • Chang, Cheol-In;Yoo, Deok-Ryong;Yum, Hwan-Seok
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.8 no.1
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    • pp.121-128
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    • 2004
  • This study aims to attain the basic data needed for the adaptation and application of polymer cement concrete as a new construction material by reviewing the various physical characteristics of polymer cement concrete following the changes in polymer type. The research found that cement concrete mixed with polymer, while it had some variation, had excellent qualities in all of compressive strength, tensile strength, water absorption, weight reducing ratio, and resistance of freezing and thawing.

Causality Between Organizational Culture and Openness for Change (조직문화와 변화개방성의 인과모형)

  • Yu, Byung-Nam;Lee, Min Yang
    • Journal of the Korea Safety Management & Science
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    • v.22 no.4
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    • pp.27-34
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    • 2020
  • This investigation was carried out in Liaoning, Shandong, and Shaanxi where classified most of their geological organizations into profit organizations, which means they must implement enterprise-oriented reform immediately. The valid 311 questionnaires were collected and used to verify the serial mediating model by AMOS 23.0. Results verified the crucial mediating effects of structural and psychological empowerment between external-focused organizational culture and openness for change. Adhocracy culture positively affects employees' openness for change through three indirect paths, including one mediator and two mediators. Market culture impacts individuals' openness for change through two indirect paths, one is through structural empowerment and another one is through two mediators. The findings provide managers in geological organizations with an empowering management practice model which could promote geological industry reform effectively.

Method of Green Infrastructure Application for Sustainable Land Use of Non-urban Area : The Case Study of Eco-delta City (비도시화 토지의 지속가능한 토지이용을 위한 그린인프라 적용기법 : 에코델타시티 사례를 중심으로)

  • Kim, Dong Hyun;Seo, Hye Jeong;Lee, Byung Kook
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.6
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    • pp.402-411
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    • 2014
  • This study suggests the method of green infrastructure (GI) application which helps proper distribution of structural GI and non-structural GI by using land characteristics assessment and performs the case study. Land assessment standard consists of land cover type, fragmentation degree, proximity degree to residential districts, and cluster degree of fragmented areas which represents the quality of green network. The result of assessment proposes the land suitability to preserve or develop and it can be utilized to choose the type of the green infrastructures.

The Structural Relationships Between Learning Agility, Employee Engagement, Career Satisfaction, and Adaptive Performance of Employees Corporate Organizations (조직구성원의 학습민첩성, 직원몰입, 경력만족, 적응수행의 구조적 관계)

  • Hyeji Jeon;Woocheol Kim
    • Journal of Practical Engineering Education
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    • v.16 no.1_spc
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    • pp.79-97
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    • 2024
  • This study confirmed the mediating effects of employee commitment and career satisfaction on the relationship between learning agility and adaptive performance. For this purpose, a survey was conducted online targeting employees of domestic companies and used for the final analysis of 329 pieces of data. Structural equations were used to analyze the relationships between variables. According the results of it was confirmed that learning agility had a statistically positive effect on employee commitment and adaptation performance, employee commitment had a positive effect on career satisfaction, and career satisfaction had a positive effect on adaptation performance. Additionally, employee commitment and career satisfaction had a significant mediating effect on the relationship between learning agility and adaptive performance. Based on these results, the academic and practical implications and future research directions for HRD are presented.

Cities as Place for Climate Mitigation and Adaptation: A Case Study of Portland, Oregon, USA (기후완화와 적용의 장소로서의 도시 - 미국 오레건주 포트랜드시 사례연구 -)

  • Chang, Hee-Jun;House-Peters, Lily
    • Journal of the Korean Geographical Society
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    • v.45 no.1
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    • pp.49-74
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    • 2010
  • Cities are major sources of greenhouse gas emissions but also suitable places for implementing proactive climate mitigation and adaptation strategies. Based on the interdisciplinary review of literature, we categorize the current discussion about urban climate mitigation and adaptation planning, policy and practices into four perspectives - sustainability science, global change science, multilevel governance, and structural engineering. While these four schools of thought have distinct perspectives rooted in different disciplinary lenses, our synthesis of the literature identifies several universal themes that are common to all of the perspectives in the context of combating threats posed by climate change. The Portland case study illustrates that a city can make changes to reduce greenhouse gas emissions and increase adaptive capacity to climate change impacts by implementing smart growth, devising local climate action plans that target emission reductions in various sectors, recognizing the interactions and influences of multiple scales of governance, and supporting the installation of various green infrastructures that contribute to green economy. Furthermore, a university can serve as a hub in this climate mitigation and adaptation arena by connecting various levels of community organizations in both public and private sectors, creating innovative research centers and spatially explicit green infrastructure, designing impact assessments and campus carbon inventories, and engaging students and the larger community through service learning.

Transciptomic Analysis of Larval Fat Body of Plutella xylostella under Low Temperature (저온조건에서 배추좀나방(Plutella xylostella) 지방체 유전자 발현 변화)

  • Kim, Kwang-Ho;Lee, Dae-Weon
    • Korean Journal of Environmental Agriculture
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    • v.38 no.4
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    • pp.296-306
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    • 2019
  • BACKGROUND: Temperature is known to be the main factor affecting development, growth and reproduction of organisms and also a physical factor directly related to insect survival. Insects as ectothermal species should be responsive to climate changes for their survival and develop various survival strategies under the unfavorable temperature such as low temperature. The purpose of this study is to identify genes contributing to adaptation of low temperature. METHODS AND RESULTS: To identify genes contributing to adaptation of low temperature, the transcriptomic data were obtained from fat body in Plutella xyostella larvae via next generation sequencing. We identified structural proteins, heat shock proteins, antioxidant enzymes, detoxification proteins, and cryoprotectant mobilization and biosynthesis-related proteins. Genes encoding chitinase, cuticular protein, Hsp23, chytochrome protein, Glutathione S transferase, and phospholipase 2 were up-regulated under low temperature. Proteins related to energy metabolism such as UDP-glycosy ltransferase, trehalase and trehalose transporter were down-regulated. CONCLUSION: When insect pests were exposed to low temperature, changes in gene expression of fat body could provide some hints for understanding temperature adaptation strategies.