• Title/Summary/Keyword: Structural Weight

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A Study on the Unstable Characteristics of Tensegrity Cable Domes According to Loading Conditions (하중조건에 따른 Tensegrity 케이블 돔의 불안정 거동 특성에 관한 연구)

  • Baek, In-Seong;Jeong, Eul-Seok;Kim, Seung-Deog
    • Proceeding of KASS Symposium
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    • 2005.05a
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    • pp.161-166
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    • 2005
  • In spatial structures with large spaces, one important issue in structures with large spaces is how to carry the weight of the roof. A tensegrity cable dome structure is a kind of soft structural system using the tension cable and compression column as a main element. The tensegrity cable dome is built into a variety of shape around the world but then a collapse accident is increasing. Owing to a collapse accident we must grip of the collapse mechanism to prevent an accident and construct the structure with safety and economy. In this study, I investigated the unstable characteristics of the Geiger-type and Flower-type tcnsegrity cable dome structures, which is the lightweight hybrid structures using compression and tension elements continuously, according to the difference of loading conditions.

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Performance Evaluation of Absorbing and Fast-Drying Fabric according to Washing (흡수 속건 소재의 세탁에 따른 성능변화 분석)

  • Shin, Ji-Young;Koo, Young-Seok
    • Textile Coloration and Finishing
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    • v.22 no.3
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    • pp.264-271
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    • 2010
  • The purpose of this study was to investigate performance evaluation of absorbing and fast-drying fabric after washing. In the comparison of absorption and fast-drying properties, there was slight difference among the materials depending on thickness, weight, and fabric structure. Absorption speed of the materials depended on the frequency of washing which might be caused by modification of fabric structure or composition fiber due to friction during washing. The ability of fast-drying of the materials was gradually decreased with the increase of washing frequency, which might be caused by fatigue accumulation on inner fiber and structural change or destruction with friction during washing.

Full-Field Stress Analysis For Prevention of Failure of Agricultural Machinery

  • Wei, Sogling
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1996.06c
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    • pp.238-246
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    • 1996
  • When the important structures or components of agricultural machinery are designed, the full-filed methods of stress analysis can provide enough information in order to obtain lighter weight and prevent failure. The photoelasticity has been applicated to solve many practical engineering problems. The coating method provides full-field information, enabling the engineers to determine the complete distribution of surface strains and directly highlighting severely strained areas, especially for the welded frames of agricultural machinery. A combined method of model and prototype for strain analysis of excavator has been successfully applied to improve design. A measuring and recording system controlled by micro-computer and application software for dynamic event was studied. It can be widely used in structural failure analysis under cyclical loading . Typical application concerned stress field of crack tip and failure analysis of some mechanical structures are introduced are in roduced briefly in this paper.

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Development of a Predictive Model for Cement Stabilised Roadbase

  • Chai Gray W.;Oh Erwin Y.;Smith Warren
    • International Journal of Highway Engineering
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    • v.8 no.2 s.28
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    • pp.31-35
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    • 2006
  • Cement stabilisation is a common method for stabilising recycled road base material and provides a longer pavement life. With cement effect, the increment of stiffness in the stabilised layer would provide better load transfer to the pavement foundation. The recycling method provides an environmentally option as the existing road base materials will not be removed. This paper presents a case study of a trial section along the North-South Expressway in West Malaysia, where the Falling Weight Deflectometer (FWD) was implemented to evaluate the compressive strength and in-situ stiffness of the cement stabilised road base material. The improvement in stiffness of the cement stabilised base layer was monitored, and samples were tested during the trial. FWD was found to be useful for the structural assessment of the cement-stabilised base layer prior to placement of asphalt layers. Results from the FWD were applied to verify the assumed design parameters for the pavement. Using the FWD, an empirical correlation between the deflection and the stiffness modulus of the pavement foundation is proposed.

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The Effect of Lead on the Growth of Carrot Callus: An Ultrastructural Study (Pb가 당근 배양세포의 성장에 미치는 영향에 대한 전자현미경적 연구)

  • Hwang, Baek;Chung, Sang-Jin;Kang, Young-Hi
    • Applied Microscopy
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    • v.9 no.1
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    • pp.13-19
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    • 1979
  • The present work has been carried out mainly to determine the effect of lead on the growth and cell organelles of Carrot (Daucus carota L.) callus. 1 mM of lead nitrate is added to the culture media R-2 and callus cells are cultured for 16 days. The growth rate is measured by fresh weight and structural changes of cell organelles is observed by electron microscope at every 4 days. The results show that lead inhibits the growth of Carrot callus and disturbs the structure of mitochondria remarkably.

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Design Guideline for Press Tool Structure of Ultra-high Strength Steel Part with Shape Optimization Technique (형상최적화 기법을 이용한 초고강도강판 성형용 프레스 금형의 구조설계 가이드라인)

  • Kang, K.H.;Kwak, J.H.;Bae, S.B.;Kim, S.H.
    • Transactions of Materials Processing
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    • v.26 no.6
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    • pp.372-377
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    • 2017
  • In this paper, an effective design procedure was proposed to design the rib of die structure for auto-body member with ultra-high strength steel (UHSS) having ultimate tensile strength (UTS) of 1.5 GPa. From analysis results of the die structure, structural safety of the die was evaluated with information such as displacement and von-Mises stress. It was concluded that the casting part could be designed in order to reduce tool deformation. A design guideline of the die structure was proposed, especially for the rib structure in the casting part with an optimization scheme and local reinforcement concept. Simulation result following the design guideline fully explained that stability of the tool structure could be obtained simultaneously with weight minimization.

Shock Resistance Analysis of a Propulsion Motor for Naval Vessels (함정용 추진전동기의 내충격성 해석)

  • Bae, Sung-Wook;Hong, Chin-Suk;Jeong, Weui-Bong;Park, Young-Su;Bin, Jae-Goo
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.20 no.12
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    • pp.1183-1189
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    • 2010
  • Shock-resistance test for a real equipment for a normal vessel is one of the difficult problem in many cases because of terrible cost and weight. An analysis technique to evaluate the shock resistance in a design stage is necessary, instead In this paper, the process to evaluate the shock resistance of a propulsion motor for naval vessels was presented based on German navy's BV043 regulation. The shock signal to impose the equipment under the test was first evaluated, and was then applied to the structural FE model of the equipment. From the transient FEA, the time history of von-Mises stress was obtained by the mode superposition method. The shock resistance was evaluated using the peak value of the von-Mises stress.

Expression of Mouse Synaptobrevin (VAMP) Gene in E. coli and its Cleavage by the Clostridium botulinum type B Toxin (Synaptobrevin (VAMP)유전자의 대장균에서의 발현 및 Clostridium botulinum type B 독소에 의한 절단)

  • 정현호;양기혁;이상달;양규환
    • Toxicological Research
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    • v.13 no.4
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    • pp.417-421
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    • 1997
  • Synaptobrevin is a kind of vesicle associated membrane proteins (VAMPs) which plays a secretary role in the neuronal synapse and was recently known as the biochemical target of botulinum neurotoxin type B. The structural gene of the synaptobrevin was cloned from mouse brain using RT-PCR technique and was seqrtenced. The deduced amino acid sequence showed that the synaptobrevin protein from mouse brain is exactly the same with that of the rat brain in the amino acid level. The synaptobrevin gene was subcloned into pET3a vector and expressed in E. coli. The molecular weight of the recombinant protein was 19 kDa as expected. Moreover, when the recombinant synaptobrevin protein was incubated with the native neurotoxin of Clostridium botulinum type B, it was cleaved by the toxin in a time dependent manner. This implies that the recombinant synaptobrevin protein and the native toxin are reacted in the same way as the native synaptobrevin did in the neuronal cells.

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Optimal Design of Micro Machine Tool for Micro Precision Machining (미소가공을 위한 마이크로 공작기계 최적설계)

  • Hwang Joon;Chung Eui-Sik;Liang Steven Y.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.477-478
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    • 2006
  • This paper presents the results of miniaturized micro milling machine tool development for micro precision machining process. Finite element analysis has been performed to know the relationship between design dimensional variables and structural stiffness in terms of static, dynamic, thermal aspects. Design optimization has been performed to optimize the design variables of micro machine tool to minimize the volume, weight and deformation of machine tool structure and to maximize the stiffness in terms of static, dynamic, and thermal characteristics. This study presents the assessment of the technology incentive for the minimization of machine tool in the quantitative context of static, dynamic stiffness, thermal resistance and thus the accuracy implications.

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Prediction Fracture Strength on Adhesively Bonded scarf Joints in Dissimilar Materials (이종재료의 경사접착이음에 대한 파괴강도의 예측)

  • 정남용
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.4 no.4
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    • pp.50-60
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    • 1995
  • Recently advantages joining dissimiliar materials and light weight material techniques have led to increasing use of structural adhesives in the various industries. Stress singulartiy occurs at the interface edges of adhesively bonded dissimilar materials. So it is required to analyze its stress singularity at the interface edges of adhesively bonded joints indissimilar materials. In this paper, the analysis method of stress singularity is studied in detail. Also, effects of the stress singularity at the interface edge of adhesively bonded scarf joints in combinations of dissimilar materials are investigated by using 2-dimensional elastic program of boundary element method. As the results, the strength evaluation method of adhesively bonded dissimilar materials using the stress singularity factor, $\Gamma$,is very useful. The fracture criterion, method of strength evaluation and prediction of fracture strength by the stress singularity factor on the adhesively bonded dissimilar materials are proposed.

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