• 제목/요약/키워드: structure of a discipline

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분야별 하부시스템의 최적화를 통합한 분해기반 MDO 방법론 (A Decomposition Based MDO by Coordination of Disciplinary Subspace Optimization)

  • 정희석;이종수
    • 대한기계학회논문집A
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    • 제26권9호
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    • pp.1822-1830
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    • 2002
  • The paper describes the development of a decomposition based multidisciplinary design optimization (MDO) method that coordinates each of disciplinary subspace optimization (DSO). A multidisciplinary design system considered in the present study is decomposed into a number of subspaces based on their own design objective and constraints associated with engineering discipline. The coupled relations among subspaces are identified by interdisciplinary design variables. Each of subsystem level optimization, that is DSO would be performed in parallel, and the system level coordination is determined by the first order optimal sensitivities of subspace objective functions with respect to interdisciplinary design variables. The central of the present work resides on the formulation of system level coordination strategy and its capability in decomposition based MDO. A fluid-structure coupled design problem is explored as a test-bed to support the proposed MDO method.

A Feasible Approximation to Optimum Decision Support System for Multidimensional Cases through a Modular Decomposition

  • Vrana, Ivan;Aly, Shady
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제9권4호
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    • pp.249-254
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    • 2009
  • The today's decision making tasks in globalized business and manufacturing become more complex, and ill-defined, and typically multiaspect or multi-discipline due to many influencing factors. The requirement of obtaining fast and reliable decision solutions further complicates the task. Intelligent decision support system (DSS) currently exhibit wide spread applications in business and manufacturing because of its ability to treat ill-structuredness and vagueness associated with complex decision making problems. For multi-dimensional decision problems, generally an optimum single DSS can be developed. However, with an increasing number of influencing dimensions, increasing number of their factors and relationships, complexity of such a system exponentially grows. As a result, software development and maintenance of an optimum DSS becomes cumbersome and is often practically unfeasible for real situations. This paper presents a technically feasible approximation of an optimum DSS through decreasing its complexity by a modular structure. It consists of multiple DSSs, each of which contains the homogenous knowledge's, decision making tools and possibly expertise's pertaining to a certain decision making dimension. Simple, efficient and practical integration mechanism is introduced for integrating the individual DSSs within the proposed overall DSS architecture.

도심 지역 및 도서 지역 초등학생들의 낮과 밤에 대한 지구 기반 관점과 우주 기반 관점의 공간표상 (Day / Night Cycle Spatial Representation of Elementary Students of Urban and Rural Area from an Earth- and a Space-based Perspective)

  • 신명경;김종영
    • 한국초등과학교육학회지:초등과학교육
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    • 제37권3호
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    • pp.309-322
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    • 2018
  • There is no doubt that science -and, therefore, science education- is central to the lives of all (NGSS, 2013). This manuscript focuses on ideas in astronomy that are at the foundation of elementary students' understanding of the discipline: the apparent motion of the sun explaining the day / night cycle on Earth. According to prior research demonstrating that neither children nor adults hold a scientific understanding of the big ideas of astronomy (NRC, 1996), understanding of concepts may base students' progress towards more advanced understanding in the domain of astronomy. We have analyzed the logic of the domain and synthesized prior research assessing children's spatial representation from an earth- and a space based perspective to develop a set of learning trajectories that describe how students' initial ideas about apparent celestial motion as they take school science can be build upon. In this study elementary students' representations were compared by their resident context including urban and rural. This study may present a first look at the use of a learning progression framework in analyzing the structure of astronomy education. We discuss how this work may eventually lead towards the development and empirical testing of how children learn to describe and explain apparent patterns of celestial motion.

세라(Shera)의 도서관 인식론 연구 (A Study on the Shera′s sociological aspect of librarianship.)

  • 남태우
    • 정보관리학회지
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    • 제20권1호
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    • pp.199-230
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    • 2003
  • 본 연구는 Jesse 또. Shera(1903-1982)가 도서관 및 도서관학과 인연을 맺게 된 동인을 연구하였다. 특히 그가 도서관 자체를 대상물(기관)로 인식하지 않고 개념으로 보고 사회인식론을 도입하여 연구한 것은 방법론뿐만 아니라 학문성을 과학으로 증명하는데 중대한 전기를 마련해 주었다. 도서관은 '인간의 기록지식을 사회적 기억으로서 체계 있게 조직하여 제공하는 사회기관이다'. 즉 도서관을 사회제도가 아닌 사회기관으로 인식하였다. 따라서 본고에서는 Shera가 도서관 및 도서관학을 사회 인식론적 관점에서 접근한 내용을 중심으로 연구하였다.

The study of frictional damper with various control algorithms

  • Mirtaheri, Masoud;Samani, Hamid Rahmani;Zandi, Amir Peyman
    • Earthquakes and Structures
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    • 제12권5호
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    • pp.479-487
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    • 2017
  • Frictional dampers are used in structural engineering as means of passive control. Meanwhile, frictional damper shave a disadvantage compared to viscous rivals since the slippage force must be exceeded to activate the device, and cannot be ideal full range of possible events. The concept of semi-active control is utilized to overcome this shortcoming. In this paper, a new semi-active frictional damper called Smart Adjustable Frictional (SAF) damper is introduced. SAF damper consists of hydraulic, electronic units and sensors which are all linked with an active control discipline. SAF acts as a smart damper which can adapt its slippage threshold during a dynamic excitation by measuring and controlling the structural response. The novelty of this damper is, while it controls the response of the structure in real time with acceptable time delay. The paper also reports on the results of a series of experiments which have been performed on SAF dampers to obtain their prescribed hysteretic behavior for various control algorithms. The results show that SAF can produce the desired slippage load of various algorithms in real time. Numerical models incorporating control simulations are also made to obtain the hysteretic response of the system which agrees closely with test results.

Steel-UHPC composite dowels' pull-out performance studies using machine learning algorithms

  • Zhihua Xiong;Zhuoxi Liang;Xuyao Liu;Markus Feldmann;Jiawen Li
    • Steel and Composite Structures
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    • 제48권5호
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    • pp.531-545
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    • 2023
  • Composite dowels are implemented as a powerful alternative to headed studs for the efficient combination of Ultra High-Performance Concrete (UHPC) with high-strength steel in novel composite structures. They are required to provide sufficient shear resistance and ensure the transmission of tensile forces in the composite connection in order to prevent lifting of the concrete slab. In this paper, the load bearing capacity of puzzle-shaped and clothoidal-shaped dowels encased in UHPC specimen were investigated based on validated experimental test data. Considering the influence of the embedment depth and the spacing width of shear dowels, the characteristics of UHPC square plate on the load bearing capacity of composite structure, 240 numeric models have been constructed and analyzed. Three artificial intelligence approaches have been implemented to learn the discipline from collected experimental data and then make prediction, which includes Artificial Neural Network-Particle Swarm Optimization (ANN-PSO), Adaptive Neuro-Fuzzy Inference System (ANFIS) and an Extreme Learning Machine (ELM). Among the factors, the embedment depth of composite dowel is proved to be the most influential parameter on the load bearing capacity. Furthermore, the results of the prediction models reveal that ELM is capable to achieve more accurate prediction.

지역공동체에 관한 연구의 접근방법과 쟁점 (Approaches and Issues on the Research about Community Based on Residential Area)

  • 채혜원;홍형옥
    • 가정과삶의질연구
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    • 제20권1호
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    • pp.33-44
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    • 2002
  • The purpose of this study is to define the concept of community based on the residential area and to review the issues on the research of community in related discipline area. The discourse about community has been developed in the field of social psychology, regional planning and architecture, housing studies, and research results by NGO. These studies of community has been dealt with social interaction and norm as well as the physical aspects of community. The research on community has been studied with the approach of structure and functionalist, systems theory approach, conflict theory approach, ecological approach, microsociological approach, and social construction approach. However, these approaches have not integrated together, but recognized community in a social or personal context. The social construction approach among these approaches suggest a useful conceptual framework for studying community in the point of view that social condition changes according to the autonomic individual. Understanding of community will influence to establishing a community norm, to planning a communal space, and to developing strategies of community. And it also takes a Important role t\ulcorner change the housing policy, institution and life style.

Experimental research on seismic behavior of SRC-RC transfer columns

  • Wu, Kai;Xue, Jianyang;Nan, Yang;Zhao, Hongtie
    • Steel and Composite Structures
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    • 제21권1호
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    • pp.157-175
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    • 2016
  • It was found that the lateral stiffness changes obvious at the transfer position of the section configuration from SRC to RC. This particular behavior leads to that the transfer columns become as the important elements in SRC-RC hybrid structures. A comprehensive study was conducted to investigate the seismic behavior of SRC-RC transfer columns based on a low cyclic loading test of 16 transfer columns compared with 1 RC column. Test results shows three failure modes for transfer columns, which are shear failure, bond failure and bend failure. Its seismic behavior was completely analyzed about the failure mode, hysteretic and skeleton curves, bearing capacity deformation ability, stiffness degradation and energy dissipation. It is further determined that displacement ductility coefficient of transfer columns changes from 1.97 to 5.99. The stiffness of transfer columns are at the interval of SRC and RC, and hence transfer columns can play the role of transition from SRC to RC. All specimens show similar discipline of stiffness degradation and the process can be divided into three parts. Some specimens of transfer column lose bearing capacity swiftly after shear cracking and showed weak energy dissipation ability, but the others show better ability of energy dissipation than RC column.

중학교 정보 교과서 비교 분석 및 개선 방안 (Comparative Content Analysis of Middle School Informatics Textbooks and Suggestions for Improvement)

  • 진영학;허민;김영식
    • 컴퓨터교육학회논문지
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    • 제13권3호
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    • pp.25-34
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    • 2010
  • 본 연구는 2007년 개정 교육과정에 의해 개발된 중학교 정보 교과서를 비교 분석하고, 이를 토대로 교과서 개선 방안을 제시하였다. 교과서는 체제와 내용의 두 가지 준거를 고려하여 분석되었으며, 수집된 자료의 분석은 내용 분석법(content analysis)을 사용하였다. 분석 결과, 교과서 체제는 전체 구성, 영역별 비중, 내용 전개 구조, 평가 유형에서 차이를 보였으며, 교과서 내용은 각 교과서가 다루는 개념, 프로그래밍 언어의 종류에서 차이를 보였다. 교과서 비교 분석의 결과를 토대로 여섯 가지의 정보 교과서 개선 방안을 제시하였으며, 이는 향후 정보 교과서 개발 시에 도움이 될 것으로 기대된다.

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Factor Structure of a Korean-Language Version of the Patient Satisfaction with Procedural Aspects of Physical Therapy Instrument

  • Lee, Hae-Jung;Adams, Roger;Oh, Tae-Young
    • The Journal of Korean Physical Therapy
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    • 제25권3호
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    • pp.160-166
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    • 2013
  • Purpose: The aim of the study was to survey satisfaction with physical therapy. Methods: After the physical therapy consultation, patients filled in a Korean-language version of the 20-tiem version of the MedRisk Instrument developed for measuring Patient Satisfaction with physical therapy. Items are scored on a five-point Likert scale ranging from strongly disagree to strongly agree. The last two items are general satisfaction and future return to the clinic. Age and gender information was also collected anonymously. Exploratory factor analysis based on principal components analysis with varimax rotation was performed on the first 18 items of the MedRisk Instrument using SPSS v.20. Results: Four factors emerged with eigenvalues greater than 1, and these cumulatively explained 55% of the total variance in item scores. The factors were labelled: Internal, External Positives, External Negatives, and Clinic Presentation. Correlations of the factor scores with the two global items ranged from 0.29 to 0.70 (both p<0.001). Gender differences were only found on the last factor, with male Korean patients rating Clinic Presentation significantly higher than females (p=0.001). Conclusion: Using factor analysis, the proposed factor structure was revealed using the positive and negative components of the external aspects of the physical therapy and by identifying a clinic presentation which contributes to patients' satisfaction. The largest proportion of the variance in Patient Satisfaction was related to clinicians' attention and behaviour. The results of the analysis provide guidelines as to the dimensions of professional physical therapy care and the implications for service delivery and patient experience.