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11.
中原经济区地处我国中部腹地,承东启西,连接南北,在全国区域分工合作、互动发展中起着重要作用,因此构建中原经济区的“区域综合竞争力”评价体系显得尤为重要。而区域经济竞争力是多因素指标综合作用的结果,因此,运用主成分分析法针对中原经济区综合竞争力建立科学评价体系,利用降维的思想,把多指标转化为少数几个综合指标,有利于从社会生产的各个方面进行综合评价,找出区域间和区域内部发展的差距,从而为区域间和区域内部的均衡发展提供政策依据。 相似文献
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The objective of this study is to experimentally investigate the cutting mechanisms of polycrystalline diamond compacts (PDC) using two different lasers: (a) a near infrared Nd:YAG laser (Neodymium-doped Yttrium Aluminum Garnet) of 1064 nm wavelength and 100 μs pulse width; and (b) a green light KTP (Potassium Titanyl Phosphate)/Nd:YAG laser of 532 nm wavelength and 120 ns pulse width. To realize the objective, the study applies polishing, lapping and etching processes to the cut-surfaces of the PDC samples. It further observes and analyzes the processed cut-surfaces with scanning electron microscopy (SEM) and Raman spectroscopy. A discussion is provided to reveal the underlying physics of the laser cutting mechanisms, and a conclusion is drawn based on the outcomes from the experimental investigation and the discussion. 相似文献
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首先指出"最近发展区"理论的内涵;然后探讨该理论与"问题解决"教学方法之间的关系以及实施要点;最后在"最近发展区"理论指导下,运用"问题解决"教学方法,围绕C程序设计课程中的一项重点及难点内容——数组及排序问题,设计了一份教学过程计划方案。 相似文献
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Adel M. AginaAuthor Vitae 《Computers in human behavior》2011,27(3):1129-1142
Because of several analytical and methodological critiques on the findings and contexts of children’s private speech (PS), self-regulation learning (SRL), and thinking aloud (TA), the present study was conducted to shed new light on the effect of the nonhuman’s/computer’s versus human’s/teacher’s intervention (C-Condition versus T-Condition) on young children’s speech use, SRL, and satisfaction during learning tasks. Four developmental measurements with novel criteria were used to measure: (1) speech analysis, (3) SRL as a function of task level selection, (3) SRL as a function of task precision, and (4) a friendly-chat questionnaire to measure children’s satisfaction. Two types of intervention (enacted versus verbal encouragement) were applied through computer-based learning environment and investigated by forty preschool children divided by their teachers between the two conditions equivalently. It was hypothesized that children who acted alone (C-Condition) were more PS productive, manifested higher SRL, task performance, and satisfaction. The results confirmed the hypothesis with no significant differential effect of the gender on performance, showed that the injudicious use of encouragement hindered the children’s regulation behavior, and proved that PS and TA elicitation were fully different. However, the results were not confirmed Vygotsky’s view and simultaneously not fully inline with Piaget’s view of self-regulation development. 相似文献
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在全球气候变暖的条件下,发展低碳农业已成为不可逆转的趋势。鄱阳湖生态经济区内农业碳资源比较丰富,且极具开发潜力,因此,低碳农业发展空间巨大。鄱阳湖生态经济区内各地政府要立足当地资源优势,充分挖掘当地农业碳资源,通过发展有机农业和循环农业,加大植树造林力度,加强湿地保护,促使农业由高碳向低碳有效转变。 相似文献
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简要介绍了广西北部湾地区的经济社会发展情况。分析了该区域面临的水资源形势和开发利用中存在的问题,提出了解决需水量与水资源总量、废水排放与水资源保护、经济跨跃式发展与水资源管理之间矛盾的措施。 相似文献
19.
袁发勇 《江汉石油职工大学学报》2013,(6):24-27
试油评价在认识油藏物性变化、油藏形状等方面具有独特的优势,试油评价数据结合录井、测井、构造、沉积等地质资料能更准确地认识地层及油藏,可为措施选层提供正确的方向,为确定措施参数提供依据。将地层测试资料应用于措施选层,已见到了良好的效果,有着广阔的应用前景。 相似文献
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This article describes a novel software tool, the KSpaceNavigator, which combines sample stage and crystallographic coordinates in a control sphere. It also provides simulated kinematic diffraction spot patterns, Kikuchi line patterns and a unit cell view in real time, thus allowing intuitive and transparent navigation in reciprocal space. By the overlay of experimental data with the simulations and some interactive alignment algorithms, zone axis orientations of the sample can be accessed quickly and with great ease. The software can be configured to work with any double-tilt or tilt–rotation stage and overcomes nonlinearities in existing goniometers by lookup tables. A subroutine for matching the polyhedral shape of a nanoparticle assists with 3D analysis and modeling. The new possibilities are demonstrated with the case of a faceted BaTiO3 nanoparticle, which is tilted into three low-index zone axes using the piezo-controlled TEAM stage, and with a multiply twinned tetrahedral Ge precipitate in Al, which is tilted into four equivalent zone axes using a conventional double-tilt stage. Applications to other experimental scenarios are also outlined. 相似文献