• Title/Summary/Keyword: 평가장치

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Identifying Dynamic Characteristics of Structures to Estimate the Performance of a Smart Wireless MA System (SWMAS의 성능 검증을 위한 구조물의 동특성 분석)

  • Heo, Gwang-Hee;Lee, Woo-Sang;Shin, Jae-Chul
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.9 no.4
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    • pp.227-234
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    • 2005
  • In this paper, a smart wireless MEMS-based accelerometer(MA) system has been designed and experimented for smart monitoring system of civil structures. Various performance and experimental tests have been carried out to evaluate whether this system is suitable for monitoring system of civil structures. First, we examined its sensitivity, resolution, and noise, specifically to evaluate the performance of the smart wireless MA system. The results of experiments enabled us to estimate performance of the MA in SWMAS in comparison to the value of data sheet from MA. Second, characteristics of model structure were analyzed by the ambient vibration test based on the NExT combined with ERA. Finally, this analysis was compared to the one that was made by FE results, and the comparison proved that a smart wireless MA system was fitted in smart monitoring system effectively.

Quantitative Evaluation of Plasticity and Extension for Extruding Body (압출성형용 소지의 가소성과 연신율의 정량화)

  • Bae, Won-Tae;Shin, Dong-Woo
    • Journal of the Korean Ceramic Society
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    • v.39 no.11
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    • pp.1048-1054
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    • 2002
  • When forming the ceramic body with plastic mass, it is needed that a quantitative testing method for plasticity, not only to evaluate the plasticity of a body, but also to control it within limits. Although many testing instruments were introduced, but no handy testing instrument for the plasticity quantitatively has been developed. In this study, modified vicat needle was designed to handily evaluate the plasicity of extruding bodies for honeycomb. The plasticity of three plastic masses was tested with this equipment. Columned needle with 2 mm diameter was adopted to measure the resistance for deformation and spherical needle with 9.5 mm diameter was adopted to measure the amount of deformation before cracking. The plasticity of three tested bodies were clearly distinguished quantitatively each other and the testing results were helpful to evaluated the workability of theses bodies. Probably, it is possible to evaluate the plasticity of various ceramic bodies with this apparatus, if suitable diameters of columns and spheres are selected.

The frog appliance for upper molar distalization: a case report (Frog appliance를 이용한 상악 대구치의 원심 이동: 증례 보고)

  • Bayram, Mehmet;Nor, Metin;Kilkis, Dogan
    • The korean journal of orthodontics
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    • v.40 no.1
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    • pp.50-60
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    • 2010
  • The purpose of this article was to evaluate the effects of a new upper molar distalization system, the Frog Appliance, on dentofacial structures in a Class II, division 1 patient. An 11-year-old girl was referred to our clinic for orthodontic treatment. She had a mild skeletal Class II malocclusion with Class II molar and canine relationship on both sides. The treatment plan included distalization of the upper first molars bilaterally followed by full fixed appliance therapy. For the upper molar distalization, a new system, the Frog Appliance, was constructed and applied. Lateral cephalometric radiographs were used to evaluate the treatment results. Distalization of the upper first molars was achieved in four months successfully, and Class I molar relationship was obtained. Total treatment time was 16 months. According to the results of the cephalometric evaluation, a nearly bodily distal molar movement with a slight anchorage loss was attained. In conclusion, the Frog Appliance was found to be a simple, ef ective, non-invasive, and compliance-free intraoral distalization appliance for achieving bilateral molar distalization.