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91.
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
92.
普通话二字组词语不同的声调组合方式 ,使前后位声调产生不同的动态变化形式。前位声调的动态变化明显表现在上声调变为低降调和中升调上 ;后位声调的动态变化则表现在调值的明显改变上。后位声调的动态变化更为普遍 ,应该引起足够的重视 相似文献
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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
97.
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
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Theory Competition and the Process of Change 总被引:1,自引:0,他引:1
The reasons why many educational change initiatives have little impact are often framed in terms of either a poorly designed
process on the part of the change initiator, or in terms of problems with the attitudes, skills and/or knowledge of those
responsible for implementation. In this paper, we seek to integrate these two perspectives more closely by focusing on their
interface and the competing theories frequently held by the change initiators and implementers. This concept of theory competition
is illustrated with a case of a national literacy initiative in New Zealand in which the change initiators wished to raise
the achievement of low performing students through the development of “learning-centred” leadership in schools and evidence-based
practice. The desired outcomes were not achieved because theories about what it means to be a successful leader in such a
situation, the data needed to undertake the type of evidence-based analysis envisioned and school personnel beliefs about
the target students were understood differently by those responsible for initiating the change and those responsible for implementing
it. 相似文献
100.
Pauline?A.?Porcaro Denise?E.?Jackson Patricia?M.?McLaughlin Cindy?J.?O’MalleyEmail authorView authors OrcID profile 《Journal of Science Education and Technology》2016,25(3):345-357
A common trend in higher education is the “flipped” classroom, which facilitates active learning during class. The flipped approach to teaching was instituted in a haematology ‘major’ class and the students’ attitudes and preferences for the teaching materials were surveyed. The curriculum design was explicit and involved four major components (1) the preparation of the students; (2) the weekly pre-class work; (3) the in-class active learning strategies and (4) closing the learning loop using formative quizzes. Each of these components is discussed in detail and was informed by sound pedagogical strategies. Several different sources of information and several freely available software tools to engage the students are discussed. Two iterations are reported here, with improved pass rate for the final examination from 47 to 48 % in the traditional class to 56–65 % in the flipped classroom approach. The majority of students (93 and 89 %) came to the class prepared, after viewing the screencasts and engaged fully with the activities within the face-to-face time. The students perceived that solving case studies (93 %) was the most beneficial activity for their learning and this was closely followed by the production of essay plans (71 %). The majority of students recommended that this approach be repeated the following year (69 and 75 %). 相似文献