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991.
LIU Dong WANG Fei HUANG Qun-xing YAN Jian-hua CHI Yong CEN Ke-fa 《浙江大学学报(A卷英文版)》2007,8(11):1853-1857
Radiative imaging of combustion flame in furnace of power plant plays an increasingly important role in combustion diagnosis. This paper presents a new method for calculating the radiative imaging of three-dimensional (3D) combustion flame based on Monte Carlo method and optical lens imaging. Numerical simulation case was used in this study. Radiative images were calculated and images obtained can not only present the energy distribution on the charge-coupled device (CCD) camera target plane but also reflect the energy distribution condition in the simulation furnace. Finally the relationships between volume ele- ments and energy shares were also discussed. 相似文献
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Kevin F. Sherry 《海外英语》2003,(9):7
Bono vs.Pretty Much Eyerything博诺vs .几乎每件事Bono befriends O’Neill and Ghana President JohnKufuor. His Case:You name it,he’s trying to fix it:hunger,education,health care,orphans,whatever makes peopleunhappy;lately,he's pushing debt relief for the ThirdWorld nations and stopping the spread of AIDS in Africa. 相似文献
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Bülent 《浙江大学学报(A卷英文版)》2010,11(2):106-114
In this study, an electro-mechanical valve (EMV) system for the intake valve ofa fottr stroke, single cylinder, overhead valve and spark ignition (SI) engine was designed and constructed. An engine with the EMV system and a standard engine were tested to observe the effects of the EMV on engine performance and emissions at different speeds under full load. The EMV engine showed improved engine power, engine torque and break specific fuel consumption (BSFC). A 66% decrease in CO emissions was also obtained with the EMV system, but hydrocarbons (HC) and NOx emissions increased by 12% and 13% respectively. 相似文献
995.
Sevda Yerdelen-Damar Yezdan Boz Sevgi Aydın-Günbatar 《Journal of Science Education and Technology》2017,26(4):394-405
This study examined the relations of preservice science teachers’ attitudes towards technology use, technology ownership, technology competencies, and experiences to their self-efficacy beliefs about technological pedagogical content knowledge (TPACK). The present study also investigated interrelations among preservice teachers’ attitudes towards technology use, technology ownership, technology competencies, and experiences. The participants of study were 665 elementary preservice science teachers (467 females, 198 males) from 7 colleges in Turkey. The proposed model based on educational technology literature was tested using structural equation modeling. The model testing results revealed that preservice teachers’ technology competencies and experiences mediated the relation of technology ownership to their TPACK self efficacy beliefs. The direct relation of their possession of technology to their TPACK self efficacy beliefs was insignificant while the indirect relation through their technology competencies and experiences was significant. The results also indicated there were significant direct effects of preservice teachers’ attitudes towards technology use, technology competencies, and experiences on their TPACK self efficacy beliefs. 相似文献
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Birgit Eickelmann 《Zeitschrift für Erziehungswissenschaft》2007,10(1):138-139
Ohne Zusammenfassung 相似文献
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Corporal punishment use in schools has decreased significantly over the past several decades; however, little research has explored the implications of such reductions in corporal punishment use. Theoretically, reducing or banning the use of corporal punishment could alter student and teacher behavior, resulting in changes in rates of other forms of discipline, such as suspension. Using nationally representative, longitudinal data from the Civil Rights Data Collection, this study estimates the relationship between corporal punishment use and suspension rates. Results from a series of fixed effects regression models suggest that reduced use or elimination of corporal punishment predicts lower rates of suspension overall but may predict higher rates of suspension in school districts serving larger proportions of racial minority students. Implications of these findings for current policy discussions around corporal punishment bans and for racial equity in school discipline are discussed. 相似文献