• 제목/요약/키워드: (B, N)-construction

검색결과 190건 처리시간 0.025초

A FAST CONSTRUCTION OF GENERALIZED MANDELBROT SETS USING MAIN COMPONENTS WITH EPICYCLOIDAL BOUNDARIES

  • Geum, Young-Hee;Lee, Kang-Sup;Kim, Young-Ik
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제14권3호
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    • pp.191-196
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    • 2007
  • The main components in the generalized Mandelbrot sets are under a theoretical investigation for their parametric boundary equations. Using the boundary geometries, a fast construction algorithm is introduced for the generalized Mandelbrot set. This fast algorithm definitely reduces the construction CPU time in comparison with the naive algorithm. Its graphic implementation displays the mysterious and beautiful fractal sets.

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수면방해에 대한 복합소음의 종류와 S/N비의 영향 (Effect of Type and S/N Ratio of Combined Noise Sources on Sleep Disturbance)

  • 이평직;심명희;전진용
    • 한국소음진동공학회논문집
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    • 제19권9호
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    • pp.960-966
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    • 2009
  • The World Health Organization(WHO) has reported the sleep disturbance as one of the adverse effects of noise. And the effect of combined noise sources on human have been investigated because community noises are seldom heard and are concurrent. Therefore, the effects of combined noise source and its S/N ratio on sleep disturbance were investigated; as a single noise source, road traffic noise was selected, and construction and movie noise were combined with road traffic noise. Tests for sleep disturbance were conducted in bedrooms and the effect on each subjects' sleep was evaluated by questionnaire. The results showed that the rate of awakening increased slightly only when the SPL of construction noise was 10 dB higher than that of road traffic noise. It was also found that the sleep disturbance was affected by the type of combined noise sources and its S/N ratio.

ICT IMPLEMENTATION FOR MATERIALS MANAGEMENT IN CONSTRUCTION PROJECTS

  • N.B. Kasim
    • 국제학술발표논문집
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    • The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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    • pp.195-200
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    • 2011
  • Construction materials usually constitute a major portion of the total cost in a building construction project. Despite the potential benefit of ICT, convincing construction organisations to embrace its use and implementation has proved a difficult task. This study seeks to identify the implementation of ICT for materials management processes in construction projects. The findings from the interviews reveal that the implementation of ICT in the materials management processes for construction projects in Malaysia is at early stage. Microsoft Excel Spreadsheet and handheld devices are found to be the common ICT tools adopted in the materials management processes. The main barrier is found to be the cost involvement at the initial stage or overall implementation of ICT in the materials management processes. Finally, this paper concludes the finding from interviews towards the ICT implementation of materials management in the construction projects.

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고강도 구조용 철강소재의 대입열 용접 시 열영향부의 조직 미세화 및 기계적 특성 향상에 미치는 TiN 및 B의 효과 (Effects of TiN and B on Grain Refinement of HAZ Microstructure and Improvement of Mechanical Properties of High-strength Structural Steel Under High Heat Input Welding)

  • 박진성;황중기;조재영;한일욱;이만재;김성진
    • 한국재료학회지
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    • 제29권2호
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    • pp.97-105
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    • 2019
  • In the current steel structures of high-rise buildings, high heat input welding techniques are used to improve productivity in the construction industry. Under the high heat input welding, however, the microstructures of the weld metal (WM) and heat-affected zone (HAZ) coarsen, resulting in the deterioration of impact toughness. This study focuses mainly on the effects of fine TiN precipitates dispersed in steel plates and B addition in welding materials on grain refinement of the HAZ microstructure under submerged arc welding (SAW) with a high heat input of 200 kJ/cm. The study reveals that, different from that in conventional steel, the ${\gamma}$ grain coarsening is notably retarded in the coarse grain HAZ (CGHAZ) of a newly developed steel with TiN precipitates below 70 nm in size even under the high heat input welding, and the refinement of HAZ microstructure is confirmed to have improved impact toughness. Furthermore, energy dispersive spectroscopy (EDS) and secondary-ion mass spectrometry (SIMS) analyses demonstrate that B is was identified at the interface of TiN in CGHAZ. It is likely that B atoms in the WM are diffused to CGHAZ and are segregated at the outer part of undissolved TiN, which contributes partly to a further grain refinement, and consequently, improved mechanical properties are achieved.

초초임계압 발전용 소재의 표면처리층의 고온 안정성 평가 (High-Temperature Stability Evaluation of Various Surface Treated Layers of Materials for Ultra-Super Critical Power Plants)

  • 류경환;송태권;이재현;김길수;이선호;엄기원
    • 한국재료학회지
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    • 제16권5호
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    • pp.329-335
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    • 2006
  • In order to improve thermal efficiency of the fossil fuel power plants, we need to develop advanced materials with superior durability in the ultra-super critical state, which requires surface modifications for superior surface properties. In this study, we coated the Incoloy 901 and 12-17Cr steels for turbine buckets and valves with nitriding, boriding, and $Cr_3C_2-NiCr$ HVOF(high velocity oxygen flow) method. Then the samples were heat treated at $650^{\circ}C$ for 100 hours in vacuum. We analyzed the evolution behaviors of nitrides such as $Fe_3N,\;Fe_4N$, and CrN and borides such as FeB and $Fe_2B$ with XRD and SEM/EDS by comparing hardnesses and compositions of the coated layers before and after the heat treatments.

WEAKLY SUFFICIENT SETS FOR WEIGHTED SPACES hΦ-(B)

  • Khoi, Le Hai
    • 대한수학회논문집
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    • 제26권2호
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    • pp.215-227
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    • 2011
  • In this paper we introduce a class $h^{-\infty}_{\Phi}(\mathbb{B})$ of weighted spaces of harmonic functions in the unit ball $\mathbb{B}$ of $\mathbb{R}^n$. We dene weakly sufficient sets in this space and give an explicit construction of countable sets of such a type. Various examples of weight functions are also discussed.

Optimal culture conditions for production of Escherichia coli Adhesin protein coupled to Escherichia coli Heat Labile Enterotoxin A2B in Escherichia coli TB1.

  • Lee, Yong-Hwa;Rhee, Dong-Kwon;Pyo, Suhk-Neung
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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    • pp.226.2-226.2
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    • 2003
  • The FimH subunit of type 1-fimbriated Escherichia coli has been determined as a major cause of urinary tract infection. To produce a possible vaccine antigen against urinary tract infection, the fimH gene was genetically linked to the Itxa2b gene, which was then cloned into the pMAL -p2E expression vector. The chimaeric construction of pMALfimH/Itxa2b was transformed into Escherichia coli TB1 and its N-terminal amino acid sequence was analyzed. (omitted)

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Expression and Characterization of Escherichia coli Adhesin Protein Linked to Cholera Toxin A2/B Subunits in Escherichia coli

  • Lee, Young-Hwa;Ryu, Dong-Kyun;Rhee, Dong-Kwon;Pyo, Suhk-Neung
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.309.2-309.2
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    • 2002
  • The FimH subunit of type l-fimbriated Escherichia coli has been determined as a major cause of urinary tract infection. To produce a possible vaccine antigen against urinary tract infection, the fimH gene was genetically coupled to the ctxa2b gene, which was then cloned into pMAL -p2E expression vector. The chimaeric construction of pMALfimH/ctxa2b was transformed into Escherichia coli TB1 and its N-terminal amino acid sequence was analyzed. (omitted)

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