• Title/Summary/Keyword: scale flexibility

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A Study on the Improvement of Structure System for the Flexible Unit Plan Designing in Apartment Housing (공동주택 단위주호의 융통성을 위한 구조방식의 개선에 관한 연구)

  • 박우장
    • Korean Institute of Interior Design Journal
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    • no.14
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    • pp.27-32
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    • 1998
  • Present structure design has a problem arising from the fact that present apartment housing design doesn't satisfy user's diverse demand. An aim of this study on searching out the alternative to solve this problem. The results of study are as follows : 1) Methods of flexible structure are analyzed to reflect user's needs and practical example of those proposed. 2) To raise the flexibility of design reinforced concrete pannel wall system are selected. The basic types of T and II for the figures of pannel are adopted. As a result it brought so much open space not having influenced on the load of construction that it enhances the flexibility of the space allocation. Also that made it easy to meet the user's demand for 8 kinds of plan types are easily designed according to the arrangement of the space and its scale. These results will become basic data of future unit plan design in apartment housing.

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Structural Dynamic Analysis of Bearingless Rotor System with Cross-shaped Composite Flexbeam (십자형 복합재 유연보 장착 무베어링 로터 시스템 구조동역학 해석)

  • Kim Do-Hyung;Lim In-Gyu;Lee Myung-Kyu;Lee In
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2004.10a
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    • pp.108-111
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    • 2004
  • Structural dynamic characteristics and aeroelastic stability of a small-scale bearingless rotor system have been investigated. A flexbeam is one of the most important component of bearingless hub system. It must have sufficient torsional flexibility as well as baseline stiffness in order to produce feathering motion. In the present paper, a cross-shaped composite flexbeam has been proposed for a guarantee of torsional flexibility and flapwise and lagwise bending stiffness. One dimensional elastic beam model was used for the construction of a structural model. Equivalent isotropic sectional stiffness was used in the blade model, and the flexbeam was regarded as anisotropic; which has ten independent stiffness quantities. CAMRAD II has been used for the analysis of structural dynamic characteristics of the bearingless rotor system. Rotational natural frequencies and aeroelastic stability at hovering have been investigated. Analysis result shows that the cross-shaped flexbeam has the rotational natural frequency tuning capacity.

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The fuel flexibility of CFBC boiler (순환유동층보일러의 연료유연성 실증연구)

  • Bae, Dal-Hee;Shun, Do-Won
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.10a
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    • pp.145-148
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    • 2008
  • Fuel flexibility of CFBC boiler was examined. Combustion characteristics of low grade coal, coal sludge, coal RDF mixture and RDF were compared. The operation result of a commercial 130TPH CFBC co-generation boiler burning a low grade Chinese coal were analysed. Burning characteristics of coal/RDF mixture and coal and industrial sludge mixture were studied in a 0.1MWth scale CFBC test rig. Also RDF fuel were tested in a 8TPH CFBC test facility. Though fuel characteristics were different, the combustion modes were all very stable. The temperature were maintained in between $800-950^{\circ}C$.

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Experimental investigation of reinforced concrete columns retrofitted with polyester sheet

  • Chang, Chunho;Kim, Sung Jig;Park, Dongbyung;Choi, Sunghun
    • Earthquakes and Structures
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    • v.6 no.3
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    • pp.237-250
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    • 2014
  • This paper experimentally investigates the seismic performance of RC columns retrofitted with Super Reinforcement with Flexibility (SRF), which is a polyester fiber reinforced polymer. A total of three specimens with a scale factor of 1/2 were constructed and tested in order to assess the structural behavior of the retrofitted RC columns. One specimen was a non-seismically designed column without any retrofit, while others were retrofitted with either one or two layers of the polyester belt with urethane as the adhesive. Static cyclic testing with a constant axial load was conducted to assess the seismic performance of the retrofitted RC columns. It is concluded that the SRF retrofitting method increases the strength and ductility of the RC columns and can also impact on the failure mode of the columns.

Set-Based Multi-objective Design Optimization at the Early Phase of Design (The Third Report) : Application to Environment-Conscious Automotive Side-Door Assembly (초기 설계단계에서의 셋 베이스 다목적 설계 최적화(제3보) : 환경문제를 고려한 자동차 사이드 도어 어셈블리에의 적용)

  • Nahm, Yoon-Eui
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.34 no.4
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    • pp.138-144
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    • 2011
  • The design flexibility and robustness have become key factors to handle various sources of uncertainties at the early phase of design. Even though designers are uncertain about which single values to specify, they usually have a preference for certain values over others. In the first and second reports of a four-part paper, a set-based design approach has been proposed for achieving design flexibility and robustness while capturing designer's preference, and its effectiveness has been illustrated with a simple vehicle side-door impact beam design problem. This report presents the applicability of the proposed design approach to the large-scale multi-objective design optimization with a successful implementation of real vehicle side-door structure design.

Flexible and Transparent Silica Aerogels: An Overview

  • Parale, Vinayak G.;Lee, Kyu-Yeon;Park, Hyung-Ho
    • Journal of the Korean Ceramic Society
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    • v.54 no.3
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    • pp.184-199
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    • 2017
  • Silica aerogels are attracting attention due to certain outstanding properties such as low bulk density, low thermal conductivity, high surface area, high porosity, high transparency and flexibility. Due to these extraordinary properties of aerogels, they have become a promising candidate in thermal superinsulation. The silica-based aerogels are brittle in nature, which constrains their large scale-application. It is necessary to achieve transparency and flexibility of silica-based aerogels at the same time and with the same porous structure for optical field applications. Therefore, the present review focuses on the different sol-gel synthesis parameters and precursors in the synthesis of flexible as well as transparent silica aerogels. Also, a brief overview of reported flexible and transparent aerogels with some important properties and applications is provided.

Near Lossless Medical Image Compression using Wavelet Transform (웨이블릿변환을 이용한 무손실에 가까운 의료영상압축)

  • Yoon, Ki-Byung;Ahn, Chang-Beom
    • Proceedings of the KOSOMBE Conference
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    • v.1995 no.11
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    • pp.113-116
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    • 1995
  • Medical image compression using the wavelet transform has been tried. Due to the flexibility in representing nonstationary image signal in both time and frequency domains and its ability to adapt human visual characteristics, wavelet transform has unique advantage in images compression. In the proposed wavelet compression original image is decomposed into multi-scale bands. Different scale factors are employed in the quantization of wavelet decomposed images in different bands. For the lowest band, a predictor is designed and error signal is entropy coded. For high scale bands, runlength coding for toro run is used with Huffman coding. From simulation with magnetic resonance images($256\times256$ size, 256 graylevels) the proposed algorithm is superior to the JPEG by more than 2.5 dB in near lossless compression (CR = 8 - 10).

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Heuristics for Synchronization of Production and Transportation Planning in the Supply Chain (공급사슬에서 생산 및 물류의 동기화를 위한 발견적 기법)

  • Jeong Jeong-U;Lee Yeong-Hae
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2006.05a
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    • pp.159-166
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    • 2006
  • The aim of synchronization of production and transportation planning in the supply chain is to increase the flexibility and to decrease various costs. The suggested model in this study synchronizes the timing to supply to a downstream manufacturer directly after production and to be consumed in a downstream manufacturer right after receipt. This model deals with the frequent delivery in small amount which is a new trend of the transportation not governed the economy of scale principle. Moreover, various types of transportation governed by the economy of scale principle or not are considered. Then, the two-phase mathematical model is suggested to obtain optimal job sequence and production quantity for each tasks. But, it is difficult to gain optimal solutions if there is a transportation governed by the economy of scale principle in the supply chain, or the size of the problem is increased. Thus, heuristic algorithms based on simulated annealing and genetic algorithm are suggested to find good solutions in the reasonable time.

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A Study on the Architectural Planning Criteria and Factors for Secondary Schools (중등학교 건축 규모계획 기준에 따른 결정인자 분석에 관한 연구)

  • Meang, Joon-Ho
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.2 no.2
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    • pp.35-51
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    • 2002
  • This study is on the architectural planning and factors for secondary schools. The methods in the approach to the results were settled. A sample of factors that affect architectural scale design were drawn from architectural design direction for a secondary school architectural scale estimation direction. These factors arc broken into primary elements and situational elements. Primary elements include students, teachers, and time. Situational elements include public use percentage, classroom percentage, unit area, coefficient of utilization, etc. The 7 architectural planning criteria to cover changes of various architectural scale design elements are the following; 1) consideration of students selection percentage, 2) consideration of the number of teachers, 3) a variety of possible classrooms, 4) organic operation, 5) efficient time management, 6) consideration of different teaching method depending on subjects, 7) coefficient of utilization with flexibility.

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The Effect of Unstable Support Surface Plank Exercise on Flexibility, Abdominal Muscle Thickness and Pain in Chronic Low Back Pain (불안정한 지지면 위에서의 플랭크 운동이 만성허리통증환자의 유연성, 배 근육 두께 및 통증에 미치는 영향)

  • Han, Woo Jeong;Son, Kyung Hyun
    • Journal of Korean Physical Therapy Science
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    • v.26 no.3
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    • pp.23-36
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    • 2019
  • Background: The purpose of this study was to investigate the effect of Plank exercise on unstable support surfaces on flexibility, abdominal muscle thickness and pain in patients with chronic back pain. Design: Randomized controlled trial. Methods: This study was performed on 16 patients with chronic back pain of ◯◯ military unit. Sixteen subjects were randomly assigned into two groups, an upper extremity trainer group (group I, n=8) and a lower extremity trainer group (group II, n=8). The subjects in group I carried out Flank exercise applying the stability trainer to their upper extremities and ones in group II carried out the same exercise applying the stability trainer to their lower extremities for 4 weeks. In order to ascertain the difference between two groups, flexibility, abdominal muscle thickness and pain were measured before and after the exercise. The flexibility was measured by sit and reach test, the thickness of the abdominal muscle was measured by using ultrasonic imaging equipment, and the pain was measured by the visual analogue scale. A paired t-test was utilized to compare changes in pain, abdominal muscle thickness and flexibility before and after flank exercise on unstable support surfaces. Analysis of Covariance (ANCOVA) was performed for ascertaining the significant differences between groups. The significance level was set by α=.05. Results: 1) The flexibilities of two groups were increased after the exercise (p<0.05). 2) In both groups, the thicknesses of rectus abdominis, external oblique abdominis, internal oblique abdominis, and transverse abdominis were all increased after the exercise (p<0.05). 3) The pains in both groups were decreased after the exercise (p<0.05). 4) In the comparisons of two groups, there were no differences in the flexibility, thickness of external oblique abdominis, internal oblique abdominis and transverse abdominis and pain (p>0.05). Whereas only thickness of Rectus abdominis was larger in the group I than in the group II (p<0.05). Conclusion: Plank exercise on the unstable support surface for 4 weeks resulted in increased flexibility, abdominal muscle thickness and pain reduction in patients with chronic back pain. Therefore, it is considered that performing flank exercise on the unstable supporting surface is suitable for the reduction of the pain in patients with chronic back pain. However, in this study, it is considered that continuous and diverse studies are needed because there was not a large difference between the groups when the upper or lower limbs are provided unstable support surfaces.