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111.
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
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114.
L-fuzzy相对T-1,相对T0与相对次T0分离性 总被引:1,自引:0,他引:1
李尧龙 《宁夏师范学院学报》2004,25(3):1-5
定义了L-fuzzy拓扑空间中的相对T-1,相对T0与相对次T0分离性,讨论了相对T-1,相对T0与相对次T0分离性的一系列性质.证明了相对T-1,相对T0与相对次T0分离性是遗传的、传递的、弱同胚不变的及可乘性等性质,并给出了一些例子。 相似文献
115.
116.
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
117.
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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渐开线少齿差齿轮副,由于是内啮合,齿轮副的齿对之间的间隙很小,在受力后轮齿变形而使得同时有多对齿啮合。本文用简明的几何推导,弹性力学的方法,推导出了轮齿受载弹性变形后同时啮合的确切齿对和承受载荷最大的齿对的载荷与总载荷的比例系数——承载能力系数。利用承载能力系数可算出更符合实际的各齿对分别承受的载荷。经样机的设计、制造和试验结果表明,本文提出的计算方法和公式是正确的,可以有效地提高齿轮副的承载能力。 相似文献
120.
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