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排序方式: 共有168条查询结果,搜索用时 250 毫秒
41.
市场营销学讲授法多样化探索 总被引:1,自引:0,他引:1
讲授法是市场营销学教学方法中的主导方法,是有效运用其他教学方法的基础。讲授法有利于在约束条件下更好地完成教学任务实现教学目标,传授多于教材的丰富知识,把"教书"和"育人"二者有效结合。根据市场营销学的学科内容和特点,探索顾名思义、延伸、举例、对比、推理分析多样化的讲授法,使其更有生机和活力,提高教学效果。 相似文献
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Based on fuzzy Petri nets, a fuzzy reasoning Petri nets (FRPN) model is defined. And then, combining fuzzy Petri nets with matrix operation, an algorithm of formalized fuzzy reasoning process is proposed. Based on the fuzziness and uncertainness of the knowledge in the disassembly process of products, a decision making model in disassembly process is established. Furthermore, taking realistic disassembly as an example, an algorithm of decision-making in disassembly sequence is discussed. The result shows that the model of decision-making has strong parallel operation ability in the disassembly process sequence. It also can make intelligent decisions based on the product information originating from each disassembly step. 相似文献
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To explore and descibe the similar situation and analogous thinking, this paper defines two kinds of decision patterns, discusses the similar measures of the state and relation of these patterns and defines the concept and the measure of similar decision model.A mechanism to correct the analogical value is presented and an optimization method based on analogizing and correcting is developed. 相似文献
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基于图像规则推理的玉米病虫草害诊断系统的设计 总被引:1,自引:0,他引:1
为解决因植保人员短缺而使玉米病虫草害不能及时得到诊断与防治,导致玉米生产减产乃至绝产的问题,本研究基于不同发病部位的病症及虫害、草害的图像知识和文本知识,采用二叉树检索算法,设计开发了玉米病虫害诊断专家系统。实际应用结果表明:系统可实现对病虫草害图像、文本和图像推理规则等知识的管理及病虫草害智能推理诊断等功能;可实现对虫害草害实现指认式诊断、解释推理过程和推理结论。通过该系统推出的玉米病虫害诊断结论,农户可针对病虫草害种类及危害程度及时防治病虫害,减少玉米生产损失。 相似文献
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Scenic quality must be assessed in forests for which recreational opportunities have become more important then traditional
wood products. Current assessment methods focus on quantitative evaluations that provide digital information to the users.
Usually, people prefer more explicit information (i.e., categorical data) than detailed quantitative data on scenic quality assessment. This paper employed fuzzy-logic terminology
to define the scenic information of forests, and then tried to develop an expert system for evaluating scenic quality based
on fuzzy reasoning. Results showed that a fuzzy-logic-based expert system using a qualitative model labeled with linguistic
terms, makes scenic beauty evaluation intuitive and understanding easy by viewing the categorical physical features of forests.
This research developed a methodology of building an expert system in this area. It is capable of providing an efficient and
useful tool for forest recreation users and forest managers. 相似文献
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Background: With mounting global environmental, social and economic pressures the resilience and stability of forests and thus the provisioning of vital ecosystem services is increasingly threatened. Intensified monitoring can help to detect ecological threats and changes earlier, but monitoring resources are limited. Participatory forest monitoring with the help of "citizen scientists" can provide additional resources for forest monitoring and at the same time help to communicate with stakeholders and the general public. Examples for citizen science projects in the forestry domain can be found but a solid, applicable larger framework to utilise public participation in the area of forest monitoring seems to be lacking. We propose that a better understanding of shared and related topics in citizen science and forest monitoring might be a first step towards such a framework.
Methods: We conduct a systematic meta-analysis of 1015 publication abstracts addressing "forest monitoring" and "citizen science" in order to explore the combined topical landscape of these subjects. We employ 'topic modelling an unsupervised probabilistic machine learning method, to identify latent shared topics in the analysed publications. Results: We find that large shared topics exist, but that these are primarily topics that would be expected in scientific publications in general. Common domain-specific topics are under-represented and indicate a topical separation of the two document sets on "forest monitoring" and "citizen science" and thus the represented domains. While topic modelling as a method proves to be a scalable and useful analytical tool, we propose that our approach could deliver even more useful data if a larger document set and full-text publications would be available for analysis.
Conclusions: We propose that these results, together with the observation of non-shared but related topics, point at under-utilised opportunities for public participation in forest monitoring. Citizen science c 相似文献
Methods: We conduct a systematic meta-analysis of 1015 publication abstracts addressing "forest monitoring" and "citizen science" in order to explore the combined topical landscape of these subjects. We employ 'topic modelling an unsupervised probabilistic machine learning method, to identify latent shared topics in the analysed publications. Results: We find that large shared topics exist, but that these are primarily topics that would be expected in scientific publications in general. Common domain-specific topics are under-represented and indicate a topical separation of the two document sets on "forest monitoring" and "citizen science" and thus the represented domains. While topic modelling as a method proves to be a scalable and useful analytical tool, we propose that our approach could deliver even more useful data if a larger document set and full-text publications would be available for analysis.
Conclusions: We propose that these results, together with the observation of non-shared but related topics, point at under-utilised opportunities for public participation in forest monitoring. Citizen science c 相似文献