• Title/Summary/Keyword: Addition with regrouping

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Effects of a Multi-Strategy Intervention Program on Multi-digit Addition with Regrouping for High School Students with Intellectual Disabilities (지적장애 고등학생의 덧셈문제 해결을 위한 다전략 중재 프로그램의 효과: 받아 올림이 있는 덧셈문제를 중심으로)

  • 최경수;김자경
    • The Journal of Special Children Education
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    • v.21 no.1
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    • pp.271-297
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    • 2019
  • Purpose: The purpose of this study was to examine the effects of a multi-strategy intervention program on addition of multi-digits with regrouping for high school students with intellectual disabilities (ID) attending a special school. Method: The multi-strategy program consisted of various intervention strategies with consideration of diverse characteristics of students with ID. In this study, A-B design was used to investigate the effects of the program for three students with ID. Results & Conclusion: The results indicated that the multi-strategy program was effective for increasing the rate of correct responses on the (two-digit number) + (one-digit number) questions with regrouping among high school students with ID. Also the multi-strategy intervention program was partially effective for the additions of multi-digits with bigger place value among the students with ID. Based on the results of this study, implications for practice and suggestions were discussed in details.

Effects of $CO_2$ and $H_2O$ Additions on Partially Premixed Counterflow Flame by Considering Nongray Gas Radiation (비회색 가스 복사를 고려한 층류대향류 부분예혼합 화염에서의 $CO_2$$H_2O$ 첨가에 따른 영향 연구)

  • Jo, Bum-Jin;Kim, Tae-Kuk
    • Journal of the Korean Society of Combustion
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    • v.10 no.3
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    • pp.10-16
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    • 2005
  • Detailed flame structures of the counterflow flames of $CH_4/Air$ formed with $CO_2$ and $H_2O$ addition are studied numerically. The detailed chemical reactions are modeled by using the OPPDIF and CHEMKIN-II code. Only the $CO_2$ and $H_2O$ are assumed to participate in radiative heat transfer while all other gases are assumed to be transparent. The discrete ordinates method(DOM) and the narrow band based WSGGM with a gray gas regrouping technique(WSGGM-RG) are applied for modeling the radiative transfer through non-homogeneous and non-isothermal combustion gas mixtures generated by the counter flow flames. The results compared with the SNB model show that the WSGGM-RG is successful in modeling the counterflow flames with non-gray gas mixture. The numerical results show that the addition of $CO_2$ and $H_2O$ to the oxidant nozzle lowers the peak temperature and the NO concentration in flame.

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Effects of Additive and Preheat on the Partially Premixed $CH_4-Air$ Counter Flow Flames Considering Non-gray Gas Radiation

  • Park Won-Hee;Chang Hee-Chul;Kim Tae-Kuk
    • Journal of Mechanical Science and Technology
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    • v.20 no.2
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    • pp.242-250
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    • 2006
  • Detailed structures of the counterflow flames formed for different inlet fluid temperatures and different amount of additives are studied numerically. The detailed chemical reactions are modeled by using the CHEMKIN-II code. The discrete ordinates method and the narrow band based WSGGM with a gray gas regrouping technique (WSGGM-RG) are applied for modeling the radiative transfer through non-homogeneous and non-isothermal combustion gas mixtures generated by the counterflow flames. The results compared with those obtained by using the SNB model show that the WSGGM-RG is very successful in modeling the counterflow flames with non-gray gas mixture. The numerical results also show that the addition of $CO_2\;or\;H_2O$ to the oxidant lowers the peak temperature and the NO concentration in flame. But preheat of fuel or oxidant raises the flame temperature and the NO production rates. $O_2$ enrichment also causes to raise the temperature distribution and the NO production in flame. And it is found that the $O_2$ enrichment and the fuel preheat were the major parameters in affecting the flame width.