• Title/Summary/Keyword: Examples

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Sample Size Calculation for Cluster Randomized Trials (임상시험의 표본크기 계산)

  • Pak, Son-Il;Oh, Tae-Ho
    • Journal of Veterinary Clinics
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    • v.31 no.4
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    • pp.288-292
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    • 2014
  • A critical assumption of the standard sample size calculation is that the response (outcome) for an individual patient is completely independent to that for any other patient. However, this assumption no longer holds when there is a lack of statistical independence across subjects seen in cluster randomized designs. In this setting, patients within a cluster are more likely to respond in a similar manner; patient outcomes may correlate strongly within clusters. Thus, direct use of standard sample size formulae for cluster design, ignoring the clustering effect, may result in sample size that are too small, resulting in a study that is under-powered for detecting the desired level of difference between groups. This paper revisit worked examples for sample size calculation provided in a previous paper using nomogram to easy to access. Then we present the concept of cluster design illustrated with worked examples, and introduce design effect that is a factor to inflate the standard sample size estimates.

Applications of Block Pulse Response Circulant Matrix and its Singular Value Decomposition to MIMO Control and Identification

  • Lee, Kwang-Soon;Won, Wan-Gyun
    • International Journal of Control, Automation, and Systems
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    • v.5 no.5
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    • pp.508-514
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    • 2007
  • Properties and potential applications of the block pulse response circulant matrix (PRCM) and its singular value decomposition (SVD) are investigated in relation to MIMO control and identification. The SVD of the PRCM is found to provide complete directional as well as frequency decomposition of a MIMO system in a real matrix form. Three examples were considered: design of MIMO FIR controller, design of robust reduced-order model predictive controller, and input design for MIMO identification. The examples manifested the effectiveness and usefulness of the PRCM in the design of MIMO control and identification. irculant matrix, SVD, MIMO control, identification.

Anything Goes?

  • Poon, Dennis;Joseph, Leonard
    • International Journal of High-Rise Buildings
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    • v.1 no.1
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    • pp.61-72
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    • 2012
  • When Cole Porter wrote the song "Anything Goes" in 1934, he did not include skyscraper examples. The recently completed Chrysler and Empire State buildings followed decades of tall building development in a logical and predictable line. Today, dramatic improvements in materials and methods of analysis, design and fabrication have given architects and engineers freedom to imagine, and contractors to build, towers in configurations never seen before. If writing now, Porter would surely have mentioned such designs to demonstrate anything goes. Or does it? This article explores the possibilities and challenges of tall building structural design through current and proposed projects. Examples include engineering buildings with outward forms that appear structurally unfavorable and taking advantage of load reduction through shaping opportunities.

Inter-sectoral Collaboration for Physical Activity Promotion (신체활동 증진을 위한 부문간 협력)

  • Koh, Kwang-Wook
    • Korean Journal of Health Education and Promotion
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    • v.30 no.4
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    • pp.69-76
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    • 2013
  • Objectives: This article intends to explore the major documents about inter-sectoral collaboration for physical activity promotion based on new paradigm. Methods: In addition to the documents after 1990s collected through several physical activity related projects of author, additional snowballing exploration has been done. Results: Globally extensive participation of stake-holders and partnership developed were strategically recommended and implementation strategy and good example were provided. In Europe individual, micro-environmental and macro-environmental specific role of major sectors were provided. Nationally series of Australian documents officialized inter-sectoral linkages from early times and Slovenian program showed examples of inter-sectoral evaluation and health indicators. U.S. national physical activity plan showed specific example of 6 guiding principles and 5 overarching strategies among 8 sectors for good inter-sectoral collaboration. In city level, healthy city approach activated. Conclusions: Various specific good examples of intersectoral physical activity collaboration could searched globally, regionally and nationally for application in Korea.

A study on the present status and examples of steel public facilities using solar power (태양광을 이용한 강구조 공공시설물의 현황과 사례 연구)

  • Yoon, Sung-Won;Kim, Hye-Seong;Kim, Dong-Won;Lee, Kyoung-Hee
    • Proceeding of KASS Symposium
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    • 2008.05a
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    • pp.221-226
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    • 2008
  • In this paper, with analysis of the public facilities using solar panel, typical bus shelters are investigated. The present status of these facilities in the field of structural design, the meaning of the bus shelters in the part of structural engineering and domestic and foreign examples are analysed. Finally, we indicate some problems in the domestic bus shelters using solar panel and suggest new ideas.

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A large Retractable Roof Structure in the World (세계의 대형 개폐식 지붕구조)

  • Par, Sun-Woo;Choi, Chui-Kyoung
    • Proceeding of KASS Symposium
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    • 2008.05a
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    • pp.227-231
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    • 2008
  • There are many retractable roof structures in the world. Retractable roofs will be classified by various factors and user, for example span length, moving mechanism, opening system, roof material and utility in over 100 examples. Therefore I will present considerations in architectural planning and structural design.

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Optimization of Frame Structures with Natural Frequency Constraints (고유진동수 제약조건을 고려한 프레임 구조물의 최적화)

  • Kim, Bong-Ik;Lee, Seong-Dae
    • Journal of Ocean Engineering and Technology
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    • v.24 no.6
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    • pp.109-113
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    • 2010
  • We present the minimum weight optimum design of cross sectional for frame structures subject to natural frequency. The optimum design in this paper employ discrete and continuous design variables and Genetic Algorithms. In this paper, Genetic Algorithms is used in optimization process, and be used the method of Elitism and penalty parameters in order to improved fitness in the reproduction process. For 1-Bay 2-Story frame structure, in examples, continuous and discrete design variables are used, and W-section (No.1~No.64), from AISC, discrete data are used in discrete optimization. In this case, Exhaustive search are used for finding global optimum. Continuous variables are used for 1-Bay 7-Story frame structure. Two typical frame structure optimization examples are employed to demonstrate the availability of Genetic Algorithms for solving minimum weight optimum of frame structures with fundamental and multi frequency.

Improvement of ID3 Using Rough Sets (라프셋 이론이 적용에 의한 ID3의 개선)

  • Chung, Hong;Kim, Du-Wan;Chung, Hwan-Mook
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1997.10a
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    • pp.170-174
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    • 1997
  • This paper studies a method for making more efficient classification rules in the ID3 using the rough set theory. Decision tree technique of the ID3 always uses all the attributes in a table of examples for making a new decision tree, but rough set technique can in advance eleminate dispensable attributes. And the former generates only one type of classification rules, but the latter generates all the possibles types of them. The rules generated by the rough set technique are the simplist from as proved by the rough set theory. Therefore, ID3, applying the rough set technique, can reduct the size of the table of examples, generate the simplist form of the classification rules, and also implement an effectie classification system.

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Daylighting Controls of Korean Traditional Houses built in Chosun Dynasty especially on examples located in northern Gyeongbuk province (경북북부지역 전통 양반가옥의 채광조절 기능에 관한 연구 -처마, 창호(窓戶), 창호지(窓戶紙)를 중심으로-)

  • Kim, Gon;Koo, Jae-Oh
    • KIEAE Journal
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    • v.4 no.3
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    • pp.79-85
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    • 2004
  • There is something valuable in Korean traditional architecture that does not change even after more than a number of years. Each design element of traditional houses has its own role to embody natural, healthy, and environment-friendly architectural planning. With traditional already-built examples located in the northern area of Gyeongbuk province, this study attempts to untangle some of the daylighting control issues in opening design. By looking at more than just photometric materials, at some threshold level, the whole of daylighting control characteristics of their openings is being surveyed from the viewpoint of geometric relationship between their roof structures and windows. As a glazing material, in addition, Korean traditional window covering paper, Changhoji, is evaluated for its transmittal performance under artificial and real skies as well.

A neural network extracting the induced stimuli for the perception of subjective contours (주관적 윤각 인식을 위한 유도 자극 추출 신경망)

  • 정은화;홍경호;김욱현
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.34C no.3
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    • pp.37-47
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    • 1997
  • Human observers perceive a contour where no line or edge is given (subject contour), such as the border between gratings of thin lines offset by half a cycle. Subjective contours occur in a wide variety of circumstances in nature. A common factor in all such figures in the perception of a surface(contour) occuluding part of a background, i.e. subject contours are always accompanied by subject surfaces. Some examples about these kinds of figures are given by kanizsa trangle or square. Ph;ysiological observations are reported in which the perceptual phenomenon that some simple examples of subject contours are perceived as images (gigures; contours) through physiological experiments was investgated. In this paper, we proposed a neural network extracting the induce dstimuli for the perception of subject contours based on the visual mechnism. This visual mechnism is proposed by hubel & wiesel's paper.

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