Kinetics study on biomass pyrolysis for fuel gas production     

陈冠益  方梦祥  ANDRIES J  骆仲泱  SPLIETHOFF H  岑可法 《浙江大学学报(A卷英文版)》2003,4(4):441-447

Kinetic knowledge is of great importance in achieving good control of the pyrolysis and gasification process and optimising system design. An overall kinetic pyrolysis scheme is therefore addressed here. The kinetic modelling incorporates the following basic steps: the degradation of the virgin biomass materials into primary products (tar, gas and semi-char), the decomposition of primary tar into secondary products and the continuous interaction between primary gas and char. The last step is disregarded completely by models in the literature. Analysis and comparison of predicted results from different kinetic schemes and experimental data on our fixed bed pyrolyser yielded very positive evidence to support our kinetic scheme. Project (No. 2001CB409600) Supported by the National Key Basic Research Program (973) of China  相似文献   

The Key Stage 3 Strategy: what kind of reform is this?     

Gordon Stobart Corresponding author  Louise Stoll 《Cambridge Journal of Education》2005,35(2):225-238

The Key Stage 3 Strategy is a complex and evolving government strategy intended to improve the education of 11‐ to 14‐year‐olds in England. This paper provides a snapshot of its development by early 2004, drawing on our evaluation of the pilot phase which began in 2000. The evolution of the Strategy, with its phased introduction of both subject and cross‐curricular strands, is described. We then examine the policy intentions and evidence base which underpin it before considering what the Strategy offers in terms of curricular and pedagogical reform. While the Strategy seeks to improve schooling for 11‐ to 14‐year‐olds, it has struggled to offer a coherent approach, though recent changes in emphasis may help. We conclude that a more radical approach to the learning needs of 11‐ to 14‐year‐olds is needed and draw evidence from international trends in middle years education.  相似文献   

China’s mass higher education: Problem,analysis, and solutions     

David?Yunchao?ChenEmail author 《Asia Pacific Education Review》2004,5(1):23-33

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Technology as a Tool: Applying an Instructional Model to Teach Middle School Students to Use Technology as a Mediator of Learning     

Angelia?Reid-GriffinEmail author  Glenda?CarterEmail author 《Journal of Science Education and Technology》2004,13(4):495-504

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A Deluge of Directives: conflict between collegiality and managerialism in the post-ERA primary school     

Rosemary Webb  Graham Vulliamy 《British Educational Research Journal》1996,22(4):441-458

The paper examines the impact of the plethora of innovations associated with the 1988 Education Reform Act (ERA) on the management of whole-school change in the primary school. Based upon qualitative data from a national sample of 50 schools in England and Wales, it documents the growing tensions between collegial and top-down managerial approaches. These are evidenced in the changing nature of working collaboratively in primary schools, in the creation of new management structures, in the me of school development plans and in the growth of quality assurance mechanisms, particularly in relation to preparation for Office for Standards in Education (OFSTED) inspections. There are conflicting interpretations of terms such as ‘collegiality’, ‘collaboration’, ‘teamwork’ and ‘whole-school approaches’ and there have been subtle shifts in their meaning and in their realisation in practice in the pre-and post-ERA context.  相似文献   

The cooking teacher: investigating gender stereotypes in a Korean kindergarten     

Liz Brooker Corresponding author  Sang‐Jin Ha 《Early Years: An International Journal of Research and Development》2005,25(1):17-30

This article discusses some findings from a small‐scale investigation of children's gendered beliefs and behaviours in a Korean kindergarten which was attempting to challenge gender stereotyping through the anti‐bias intervention of a ‘cooking curriculum’. A sample of 14 children, some with ‘working’ mothers and some with ‘housewife’ mothers, was observed for two months, and informally interviewed on several occasions. The children's mothers were also interviewed. The findings are situated in the context of the changing, but still traditional, culture of Korean society, as well as in the contexts of early childhood education and theories of gender acquisition. They confirm that, although children are highly likely to reproduce the beliefs current in their home environment, they are open to reconstructing these views when actively challenged to consider alternatives, either by the school curriculum or by engaging in debate with a researcher or practitioner. The nature of the ‘alternative’ views available may however be problematic.  相似文献   

Arithmetic nature of sums of certain convergent series     

S?D?AdhikariEmail author  N?SaradhaEmail author 《Resonance》2002,7(11):35-46

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Teaching Undergraduate Mathematics on the Internet     

Johann?EngelbrechtEmail author  Ansie?Harding 《Educational Studies in Mathematics》2005,60(2):253-266

This is Part 2 of a two-part study of how APOS theory may be used to provide cognitive explanations of how students and mathematicians might think about the concept of infinity. We discuss infinite processes, describe how the mental mechanisms of interiorization and encapsulation can be used to conceive of an infinite process as a completed totality, explain the relationship between infinite processes and the objects that may result from them, and apply our analyses to certain mathematical issues related to infinity.  相似文献   

Improving the precision of the keyword-matching pornographic text filtering method using a hybrid model     

苏贵洋  李建华  马颖华  李生红 《浙江大学学报(A卷英文版)》2004,5(9):1106-1113

With the flooding of pornographic information on the Internet, how to keep people away from that offensive information is becoming one of the most important research areas in network information security. Some applications which can block or filter such information are used. Approaches in those systems can be roughly classified into two kinds:metadata based and content based. With the development of distributed technologies, content based filtering technologies will play a more and more important role in filtering systems. Keyword matching is a content based method used widely in harmful text filtering. Experiments to evaluate the recall and precision of the method showed that the precision of the method is not satisfactory, though the recall of the method is rather high. According to the results, a new pornographic text filtering model based on reconfirming is put forward. Experiments showed that the model is practical, has less loss of recall than the single keyword matching method, and has higher precision.  相似文献   

Differential Reading,Naming, and Transcribing Speeds of Japanese Romaji and Hiragana     

Jun?YamadaEmail author  Che?Kan?Leong 《Reading and writing》2005,18(4):303-323

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