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This paper presents an approach to understanding problem solving and innovation from the perspective of engagement. The approach is derived primarily from two research projects undertaken over the last 5 years. The first one into the apparent Comparison Parado in Soft Systems Methodology, and the second an 18-month research program into the social reality implied by Soft Systems Methodology. Engagement is argued to be the innovation of a framework of ideas within a social context. In this sense engagement is an extension of the nature in which humans take ideas and place them inside a social context and use this as a platform to make sense of their environment and take action in such surroundings with an eye to understanding, learning, meaning, adaptation, innovation, and interpretation of such situations. Therefore, this paper presents a conjectured model of Engagement that is argued to be useful in helping to manage social complexity and real-world problem-solving activity. The paper positions engagement as a purely theoretical approach with multidisciplinary applications for whoever would like to use it. 相似文献
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During meiosis, the reductional segregation of homologous chromosomes at the first meiotic division requires reciprocal exchange (crossing over) between homologs. The number of crossovers is tightly regulated (one to two per homolog in mice), and their distribution in the genome is not random-recombination 'hot' and 'cold' regions can be identified. We developed a molecular assay to study these events directly in mouse germ cells. This analysis was developed with reference to the proteosome subunit beta type 9 (Psmb9, previously called Lmp2) hot-spot region identified through genetic analysis. Here we show that this hot spot is an initiation site of meiotic recombination on the basis of two observations: (i) crossover density is maximal in an interval of 210 bp and decreases on both sides of this region; (ii) a high frequency of gene conversion is found in the region of highest crossover density. We then used this strategy to carry out the first temporal analysis of meiotic recombination in mouse spermatogenesis and demonstrate that crossover events occur during the pachytene stage of meiotic prophase. 相似文献
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基于单神经元自适应PSD算法用于混沌镇定控制 总被引:1,自引:1,他引:0
为了镇定混沌系统的不稳定周期轨道,提出了一种基于单神经元自适应PSD算法的状态延迟反馈法用于混沌的镇定控制。仿真结果表明,该算法不仅能够自适应地完成控制参数的整定过程,而且具有适用范围广、镇定时间短、抗干扰能力强等优点。 相似文献
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基于一篇文章所引用的参考文献和该文的被引频次两个维度,提出了衡量该文外显成长度的相对指标.该研究涉及的引用数据及每条参考文献的被引数据均来自网络版科学引文索引(Web of Science),检索日期为2010年4月最后一周. 相似文献
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Effect of weld microstructure on brittle fracture initiation in the thermally-aged boiling water reactor pressure vessel head weld metal
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Noora Hytönen Zai-qing Que Pentti Arffman Jari Lydman Pekka Nevasmaa Ulla Ehrnstén Pål Efsing 《矿物冶金与材料学报》2021,28(5):867-876
Effects of the weld microstructure and inclusions on brittle fracture initiation are investigated in a thermally aged ferritic high-nickel weld of a reactor pressure vessel head from a decommissioned nuclear power plant.As-welded and reheated regions mainly consist of acicular and polygonal ferrite,respectively.Fractographic examination of Charpy V-notch impact toughness specimens reveals large inclusions(0.5-2.5μm)at the brittle fracture primary initiation sites.High impact energies were measured for the specimens in which brittle fracture was initiated from a small inclusion or an inclusion away from the V-notch.The density,geometry,and chemical composition of the primary initiation inclusions were investigated.A brittle fracture crack initiates as a microcrack either within the multiphase oxide inclusions or from the debonded interfaces between the uncracked inclusions and weld metal matrix.Primary fracture sites can be determined in all the specimens tested in the lower part of the transition curve at and below the 41-J reference impact toughness energy but not above the mentioned value because of the changes in the fracture mechanism and resulting changes in the fracture appearance. 相似文献
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