• Title/Summary/Keyword: science history

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Godel's Disjunctive Conclusion

  • 현우식
    • Journal for History of Mathematics
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    • v.13 no.1
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    • pp.137-141
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    • 2000
  • This paper discusses Godel's Disjunctive Conclusion in terms of cognitive science and his Incompleteness Theorems from a metamathematical perspective.

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Time-history analysis based optimal design of space trusses: the CMA evolution strategy approach using GRNN and WA

  • Kaveh, A.;Fahimi-Farzam, M.;Kalateh-Ahani, M.
    • Structural Engineering and Mechanics
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    • v.44 no.3
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    • pp.379-403
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    • 2012
  • In recent years, the need for optimal design of structures under time-history loading aroused great attention in researchers. The main problem in this field is the extremely high computational demand of time-history analyses, which may convert the solution algorithm to an illogical one. In this paper, a new framework is developed to solve the size optimization problem of steel truss structures subjected to ground motions. In order to solve this problem, the covariance matrix adaptation evolution strategy algorithm is employed for the optimization procedure, while a generalized regression neural network is utilized as a meta-model for fitness approximation. Moreover, the computational cost of time-history analysis is decreased through a wavelet analysis. Capability and efficiency of the proposed framework is investigated via two design examples, comprising of a tower truss and a footbridge truss.

Analysis of Intellectual Structure of Subject Specialty through Author Co-citation (전문영역의 주제구조분석 - 저자공인용에 근거하여 -)

  • Cho Myeung-Hee
    • Journal of the Korean Society for Library and Information Science
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    • v.22
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    • pp.331-360
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    • 1992
  • This research presents author co-citation analysis of the subject area in the humanities - Korean history. Three approaches to multivariate analyses were used to display the inter-author relationships in the similarity matrix. Data on co-citation of sixty seven authors for the period of 1980­1989 were extracted from the database constructed by author. The author's name, here refers to a body of writings by a person, is the unit of analysis. The data were subjected to non-metric multidimensional scaling program create two-dimensional map of authors. Authors with similarity are clustered using hierarchical agglomerative procedure and it is found that five clusters in Korean history represent primarily research specializations. Author map of Korean history reveals the first dimension corresponding to subject orientation of authors and the second dimension corresponds to research method or research style. In factor analysis, each factor reflects research specialty made up of authors, and factor locadings demonstrate the breadth or concentration of sixty seven authors' scholarly contributions on Korean history. It is demonstrated that the· specific methodology employed by this research, author co-citation analysis, is useful to represent the intellectual structure of Korean history.

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Retrieving the Time History of Displacement from Measured Acceleration Signal

  • Han, Sangbo
    • Journal of Mechanical Science and Technology
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    • v.17 no.2
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    • pp.197-206
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    • 2003
  • It is intended to retrieve the time history of displacement from measured acceleration signal. In this study, the word retrieving means reconstructing the time history of original displacement signal from already measured acceleration signal not just extracting various information using relevant signal processing techniques. Unlike extracting required information from the signal, there are not many options to apply to retrieve the time history of displacement signal, once the acceleration signal is measured and recorded with given sampling rate. There are two methods, in general, to convert measured acceleration signal into displacement signal. One is directly integrating the acceleration signal in time domain. The other is dividing the Fourier transformed acceleration signal by the scale factor of - $\omega$$^2$and taking the inverse Fourier transform of it. It turned out both the methods produced a significant amount of errors depending on the sampling resolution in time and frequency domain when digitizing the acceleration signals. A simple and effective way to convert the time history of acceleration signal into the time history of displacement signal without significant errors is studied here with the analysis on the errors involved in the conversion process.

An Analysis of Elements for Teacher Librarians' Educational Information Services Embedded in Common Inquiry Tasks of World History Territory in Korean Middle School History Studies (중학교 「역사」 교과서 세계사 영역의 공통 탐구 과제에 포함된 사서교사의 교육정보서비스 요소 분석)

  • Song, Gi-Ho
    • Journal of the Korean Society for Library and Information Science
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    • v.50 no.2
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    • pp.5-23
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    • 2016
  • The purpose of this study is to analyze common inquiry tasks of middle school history textbooks and find out it's implications on teacher librarians' educational information services. There are 84 common inquiry tasks according to examinations of inquiry tasks related to world history in 18 kinds of middle school history textbooks. Results of the analysis show that almost all of common inquiry tasks of world history make middle school students who should resolve them research the pictures and reading materials included in the textbooks individually and verbalize under the information literacy process. Compared with information literacy process of the "Library and Information Skills" for middle schools, the First step of task definition and figuring out information needs and the Third step of representation of information are being implemented. For this reason, teacher librarian could reduce history studies teachers' burden of running the class and promote students' inquiry activities by teaching skills of information analysis and interpretation, synthesis and organization and evaluation of their information literacy process and results.

Exploring the Characteristics of STEAM Program Developed by Docents and its educational impact in the Natural History Museum

  • Park, Young-Shin;Park, Jin-Hee;Ryu, Hyo-Suk
    • Journal of the Korean Society of Earth Science Education
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    • v.7 no.1
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    • pp.75-90
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    • 2014
  • The purpose of this study was to explore the characteristics of STEAM program developed and implemented by two docents and its educational impact for the use of natural history museum. Two docents developed this program with the help of science educators who ran five times of workshop during five months. The STEAM program implemented in the natural history museum demonstrated the following characteristics. The exhibitions in museum were reached by visitors only for learning science concepts (S) out of five components in STEAM. The other components, T (technology) and E (engineering), were delivered through lectures in the room, not exhibition hall. M (Mathematics)was achieved by guessing the animal's size, or calculating the walking or running speed with the clue of foot prints. The three phases of STEAM program (presentation of context, creatively design the investigation, and emotional touch) were explicitly implemented but partially successful. Two docents participating in this study responded that they formed new or extended the understandings about STEAM education, but they had the difficulties in implementing STEAM program for various type of visitors. All visitors who participated in this study displayed the favorable responses in educational impact by STEAM program in natural history museum. The heavier emphasis on E and T of STEAM program is recommended through community-based learning. In addition, educator professional program through which docents can bridge theory into practice is suggested for revitalization of STEAM education.

Analysis of Elementary School Children's Concepts in Evolution Based on Science History (과학사적 진화개념 발달 단계에 기초한 초등학생들의 진화 개념 분석)

  • Lee Mi-Sook;Oh Se-Pyoung;Lee Kil-Jae
    • Journal of Korean Elementary Science Education
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    • v.24 no.2
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    • pp.145-159
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    • 2005
  • Students' alternative concepts of evolution are similar to misconcepts and disputes which scientists had in science history. The aims of this study are to analyze the elementary children's concept in evolution based on science history. Lee (2004)'s two tests were applied to 6th grade to investigate the children's evolution concepts and genetic concepts related to the historical development of the evolution concepts. The test results were analyzed in accordance with 4 stages of science history based on Lee (2004)'s method. These stages are divided to stage 1 (Before Lamarck), stage 2 (Lamarck), stage 3 (Darwin), stage 4 (After Darwin). The major results are as follows. Most of elementary school children are fixed to the stage 2. They usually do not show the consistency of evolution concepts in the three dimensional aspects such as mechanism, time, and subjects. Many children do not have concrete meaning of gene, inheritance, sexual reproduction, mutation and could not connect these concetps and process of evolution. Also, they believe the inheritance of acquired traits and spontaneous generation. Therefore it is confirmed that they still have similar misconcepts and disputes which scientists had in transition time between stage 2 and 3 and most of children already have strong Lamarckian thought acquired from daily life experience before learning about natural selection and evolution.

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The Improvements of Classification System of the Auxiliary Sciences of History Field in the KDC 5th Edition (KDC 역사보조학 분야 분류체계의 개선방안)

  • Lee, Changsoo
    • Journal of Korean Library and Information Science Society
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    • v.44 no.3
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    • pp.29-49
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    • 2013
  • Among the auxiliary sciences of history field in the KDC 5th edition, several classification system problems are found with the fields of Archaeology, Diplomatics, Archival Science, Genealogy, and Biography. The purpose of this study is to propose their improvements. To achieve this purpose, first, this study compared and analyzed the Auxiliary Sciences of History field of LCC, DDC, KDC, NDC, UDC, CLC. Second, this study investigated the actual conditions of KDC in the library field to diagnose several application problems. Finally, based on the findings, the improvements of KDC were suggested.

History / Aggregate Operator for Spatio-Temporal Databases (시공간 데이터베이스를 위한 history 집계 연산자)

  • 이종연
    • Proceedings of the Korean Information Science Society Conference
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    • 2001.10a
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    • pp.106-108
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    • 2001
  • 기존의 관계형 데이터베이스 시스템은 기본적으로 count, max, min, sum, avg의 집계 함수(aggregate functions)를 제공하며, UBMS에 따라 다양한 집계 연산자를 추가로 지원한다. 시공간 데이터베이스는 기본적인 공간 정보뿐만 아니라 시간 흐름에 따른 이력 정보를 취급하므로 데이터베이스로부터 자유로운 이력(history) 정보의 검색 기능이 요구되고 있다. 따라서, 본 연구에서는 시공간 데이터베이스로부터 이력을 자동으로 검색할 수 있는 새로운 집계 연산자, ‘history’를 제안하고, 그 처리 알고리즘과 SQL3에서 탐색 질의 표현법을 제안한다. 결과적으로, 제안된 이력 집계 연산자는 향후 SQL3리 질의 표현 능력의 제고에 기여할 것이다.

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