• Title/Summary/Keyword: Multi-objectives

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Multi-objective topology and geometry optimization of statically determinate beams

  • Kozikowska, Agata
    • Structural Engineering and Mechanics
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    • v.70 no.3
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    • pp.367-380
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    • 2019
  • The paper concerns topology and geometry optimization of statically determinate beams with arbitrary number of supports. The optimization problem is treated as a bi-criteria one, with the objectives of minimizing the absolute maximum bending moment and the maximum deflection for a uniform gravity load. The problem is formulated and solved using the Pareto optimality concept and the lexicographic ordering of the objectives. The non-dominated sorting genetic algorithm NSGA-II and the local search method are used for the optimization in the Pareto sense, whereas the genetic algorithm and the exhaustive search method for the lexicographic optimization. Trade-offs between objectives are examined and sets of Pareto-optimal solutions are provided for different topologies. Lexicographically optimal beams are found assuming that the maximum moment is a more important criterion. Exact formulas for locations and values of the maximum deflection are given for all lexicographically optimal beams of any topology and any number of supports. Topologies with lexicographically optimal geometries are classified into equivalence classes, and specific features of these classes are discussed. A qualitative principle of the division of topologies equivalent in terms of the maximum moment into topologies better and worse in terms of the maximum deflection is found.

Development of MURCC code for the efficient multi-unit level 3 probabilistic safety assessment

  • Jung, Woo Sik;Lee, Hye Rin;Kim, Jae-Ryang;Lee, Gee Man
    • Nuclear Engineering and Technology
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    • v.52 no.10
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    • pp.2221-2229
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    • 2020
  • After the Fukushima Daiichi nuclear power plant (NPP) accident, level 3 probabilistic safety assessment (PSA) has emerged as an important task in order to assess the risk level of the multi-unit NPPs in a single nuclear site. Accurate calculation of the radionuclide concentrations and exposure doses to the public is required if a nuclear site has multi-unit NPPs and large number of people live near NPPs. So, there has been a great need to develop a new method or procedure for the fast and accurate offsite consequence calculation for the multi-unit NPP accident analysis. Since the multi-unit level 3 PSA is being currently performed assuming that all the NPPs are located at the same position such as a center of mass (COM) or base NPP position, radionuclide concentrations or exposure doses near NPPs can be drastically distorted depending on the locations, multi-unit NPP alignment, and the wind direction. In order to overcome this disadvantage of the COM method, the idea of a new multiple location (ML) method was proposed and implemented into a new tool MURCC (multi-unit radiological consequence calculator). Furthermore, the MURCC code was further improved for the multi-unit level 3 PSA that has the arbitrary number of multi-unit NPPs. The objectives of this study are to (1) qualitatively and quantitatively compare COM and ML methods, and (2) demonstrate the strength and efficiency of the ML method. The strength of the ML method was demonstrated by the applications to the multi-unit long-term station blackout (LTSBO) accidents at the four-unit Vogtle NPPs. Thus, it is strongly recommended that this ML method be employed for the offsite consequence analysis of the multi-unit NPP accidents.

A Study on the Analysis of Educational Objectives of 'Library and Information Life' Textbooks Based on the Eisner Curriculum (아이즈너 교육과정에 의한 '도서관과 정보생활' 교과서 교육목표 분석에 관한 연구)

  • Byeong-Kee Lee
    • Journal of the Korean Society for Library and Information Science
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    • v.58 no.2
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    • pp.57-80
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    • 2024
  • Eisner emphasized the importance of problem-solving objectives and expressive objectives in addition to behavioral objectives, and communication through multiple modalities including linguistic, visual, aural, spatial, gestural modes. This study analyzes 'Libraries and Information Life,' a textbook developed for information literacy instruction, by dividing it into educational objectives types(behavioral, problem-solving, expressive) and multimodal modes(linguistic, visual, auditory, spatial, and gestural), and seeks to derive implications for setting educational objectives for information literacy instruction and developing textbooks. The textbook has four volumes for elementary low-grade, elementary high-grade, middle school, and high school levels. Educational objectives were extracted from the textbooks, and 3 librarian-teachers were engaged in the analysis of these objectives. The main findings and implications of this study are as follows. First, when looking at the types of educational objectives, the proportion of behavioral objectives was found to be excessively high, and there is a need to strengthen the proportion of problem-solving objectives and expressive objectives. Second, problem-solving objectives tend to overlap with behavioral objectives, indicating a need to develop problem-solving objectives with defined conditions and solution requirements. Third, expressive objectives concentrated in specific units need to be placed evenly in other units. Fourth, in the case of multi-modality mode, the proportion of the linguistic mode must be reduced, the proportion of the visual, auditory, spatial, and gestural modes must be increased, and it is necessary to set educational objectives with clear characteristics of each mode.

Association between Self-esteem and Health Behavior of the Children with Multi-cultural Family Background (다문화가정 초등학생의 자아존중감과 건강행위 간의 관련성)

  • Yoo, Bit-Na;Park, Kyoung-Ok;Choi, Jin-Young
    • The Journal of Korean Society for School & Community Health Education
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    • v.11 no.1
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    • pp.41-55
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    • 2010
  • Objectives: This study was conducted to identify the characteristics of health behavior and self-esteem and the relationship between the two factors among elementary school students with multi-cultural family background. Participants: Survey participants were 87 multi-cultural family children who lived in Seoul and Kyoungi areas and were registered in the local elementary schools. Methods: Data collection was conducted by face-to-face interview survey. Elementary education majored undergraduate students who participated in the education support program for multi-cultural family children in the Ministry of Education and Science and primary researcher of this study interviewed the target students and finished the survey questionnaire based on the students' responses. Survey included general characteristics, multi-cultural family characteristics, self-esteem, and (physical, mental, and social) health behavior. Results: 1. The self-esteem scores of the multi-cultural families children were greater in girl than boys among the children whose parents were graduated from college or more, and whose father had his job. The participants' health behavior scores were different by mothers' educational level. 2. The better they speak in English the greater the self-esteem scores. There was no statistical difference in health behavior scores by the participants' multi-cultural family background. 3. Self-esteem had moderate level correlation with health behavior (r= .56, p= .00) including all sub-categories of physical, mental, and social health. Conclusions: Positive self-esteem level is more sensitive to explain multi-cultural family children's health behaviors, which means that self-esteem is an important factor determining multi-cultural children's health behaviors and their health status in future. Therefore, more research to identify the factors related to health behaviors should be supported and the health promotion programs utilizing self-esteem should be developed for the child and youth with multi-cultural family backgrounds.

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A Study on the Perception of Public Library Users on Multi-cultural Services (공공도서관 이용자의 다문화서비스에 대한 인식 연구)

  • Kim, Giyeong;Oh, Haeyeon
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.25 no.3
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    • pp.77-100
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    • 2014
  • This study aims to investigate the perception of public library users, who are local residences, on the multi-cultural services in public libraries using a series of statistical analyses on a questionnaire survey. The objectives of multi-cultural policies by Korean government are to foster assimilation of the multi-cultural people, social unification of Korean (local) communities, and cultural diversity in the communities. The results from the analyses show that the multi-cultural services in public libraries are understood from the unification and assimilation point of views, and that the perception of the multi-cultural services in public libraries is affected by the libraries' marketing activities, such as advertisements and participation. For the sustainable provision of the services, we suggest that the libraries would better consider 1) multi-oriented services with cultural diversity, assimilation, and social unification, 2) relationship with other multi-cultural agencies in a community, and 3) the perception of local residences on the services in public libraries.

A knowledge-based DSS for the decision making under multi-objectives

  • 최용선;김성의
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1992.04b
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    • pp.267-277
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    • 1992
  • 본 논문은 다목적선형계획법을 위한 Decision Support System ASEOV-VIM을 소개하고 있다. ASEOV-VIM에는 1) efficient solution set전체에 대한 개괄과 search direction을 제새하는 ASEOV; 2) decision maker의 preference information을 도출해내는 VIM; 3) 위 두 부분간의 interface로 활용되는 Mediator등 3개의 하부시스템이 있다. ASEOV-VIM은 TURBO-C를 이용하여 personal computer에 구현되었다.

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Influences of Parental Attachment of Elementary School Students' Perception on Anger and Anger Expressions of Children in Multi-cultural Families (다문화가정 초등학생의 부모에 대한 애착관계가 분노와 분노표현에 미치는 영향)

  • Moon, So-Hyun;An, Hyo-Ja
    • The Journal of Korean Society for School & Community Health Education
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    • v.13 no.1
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    • pp.33-43
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    • 2012
  • Objectives: The study has a purpose of contributing to understanding children of multi-cultural families and healthy development of children by examining influences of parental attachment perceived by the children on their anger trait and anger expressions. Methods: The data were collected from 113 students in grade 4~6, and analyzed using descriptive statistics, t-test, pearson correlation coefficient by the SPSS/PC 18.0 program. Results: The result showed the stable attachment with parents significantly influences children's anger and expression(anger out/control). And mother's attachment was significantly stronger than father's attachment, especially mutual trust and communication. Father's attachment had significantly negative influences state-trait anger and anger out/in, and mother's attachment had significantly negative influences state-trait anger and anger out. Actually father's attachment had stronger influences children's anger and anger expression. Conclusions: There was relationship between father's attachment and anger trait/ expression by children of multi-cultural families. For the effective management of multi-cultural children's anger, programs focusing on improving father-child relationships need to be established.

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Multidisciplinary Multi-Point Design Optimization of Supersonic fighter Wing Using Response Surface Methodology (반응면 기법을 이용한 초음속 전투기 날개의 다학제간 다점 설계)

  • Kim Y. S.;Kim J. M.
    • 한국전산유체공학회:학술대회논문집
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    • 2004.10a
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    • pp.173-176
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    • 2004
  • In this study, the multidisciplinary aerodynamic-structural optimal design is carried out for the supersonic fighter wing. Through the aeroelastic analyses of the various candidate wings, the aerodynamic and structural performances are calculated such as the lift coefficient, the drag coefficient and the deformation of the wing. In general, the supersonic fighter is maneuvered under the various flight conditions and those conditions must be considered all together during the design process. The multi-point design, therefore, is deemed essential. For this purpose, supersonic dash, long cruise range and high angle of attack maneuver are selected as representative design points. Based on the calculated performances of the candidate wings, the response surfaces for the objectives and constraints are generated and the supersonic fighter wing is designed for better aerodynamic performances and less weights than the baseline. At each design point, the single-point design is performed to obtain better performances. Finally, the multi-point design is performed to improve the aerodynamic and structural performances for all design points. The optimization results of the multi-point design are compared with those of the single-point designs and analyzed in detail.

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Optimization of multi-water resources in economical and sustainable way satisfying different water requirements for the water security of an area

  • Gnawali, Kapil;Han, KukHeon;Koo, KangMin;Yum, KyungTaek;Jun, Kyung Soo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2019.05a
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    • pp.161-161
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    • 2019
  • Water security issues, stimulated by increasing population and changing climate, are growing and pausing major challenges for water resources managers around the world. Proper utilization, management and distribution of all available water resources is key to sustainable development for achieving water security To alleviate the water shortage, most of the current research on multi-sources combined water supplies depends on an overall generalization of regional water supply systems, which are seldom broken down into the detail required to address specific research objectives. This paper proposes the concept of optimization framework on multi water sources selection. A multi-objective water allocation model with four objective functions is introduced in this paper. Harmony search algorithm is employed to solve the applied model. The objective functions addresses the economic, environmental, and social factors that must be considered for achieving a sustainable water allocation to solve the issue of water security.

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A Constrained Multi-objective Computation Offloading Algorithm in the Mobile Cloud Computing Environment

  • Liu, Li;Du, Yuanyuan;Fan, Qi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.9
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    • pp.4329-4348
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    • 2019
  • Mobile cloud computing (MCC) can offload heavy computation from mobile devices onto nearby cloudlets or remote cloud to improve the performance as well as to save energy for these devices. Therefore, it is essential to consider how to achieve efficient computation offloading with constraints for multiple users. However, there are few works that aim at multi-objective problem for multiple users. Most existing works concentrate on only single objective optimization or aim to obtain a tradeoff solution for multiple objectives by simply setting weight values. In this paper, a multi-objective optimization model is built to minimize the average energy consumption, time and cost while satisfying the constraint of bandwidth. Furthermore, an improved multi-objective optimization algorithm called D-NSGA-II-ELS is presented to get Pareto solutions with better convergence and diversity. Compared to other existing works, the simulation results show that the proposed algorithm can achieve better performance in terms of energy consumption, time and cost while satisfying the constraint of the bandwidth.