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61.
62.
探究了多层住宅小型砼空心砌块墙体裂缝产生的原因及防治措施,对指导目前工程的设计及施工有一定的实用价值。 相似文献
63.
段富贵 《洛阳师范学院学报》2002,21(5):117-118
观察是人们获取知识信息的第一步 .观察能力的高低会对学生的学习产生重要的影响 .在化学教学中 ,有意识、有计划地培养学生的观察能力 ,使他们能够善于观察 ,并进行正确的思维是提高学生素质的一个重要环节 .教师指导的最终目标在于培养学生的独立观察能力 . 相似文献
64.
本文给出了求解扰动后新方程组的直接方法,它简捷,计算量和存贮量都不大,数值结果也表明它是相当有效的。对于替换多个方程的情况,用本方法均可直接处理。 相似文献
65.
A new site-specific nutrient management approach was developed to break the apparent attainable yield barrier of 6 t·ha−1 in the double rice cropping system of Zhejiang. On-farm experiments involving 21 rice-growing farmer families and NPK long-term
experiments commenced in 1997 in the central part of Zhejiang Province to assess the status of soil fertility and productivity
under intensive rice-rice cropping. A new site-specific nutrient management (SSNM) approach has been developed for this studied
area. Field-specific fertilizer recommendations are calculated considering indigenous nutrient supply, reasonable grain yield
targets and corresponding nutrient demand, nutrient balance and nutrient use efficiency, as well as socio-economic factors.
The agronomic performance of SSNM was tested against the farmer's fertilizer practice (FFP) in four 1998–1999 cropping seasons.
Across seasons and years, SSNM consistently increased plant nutrient uptake, grain yield and profit by about 10%–15% compared
to the FFP. Yield levels of 7.5 t·ha−1 or more seem achievable and sustainable through introduction of SSNM and improved extension services in Zhejiang Province.
Project supported by the International Fertilizer Industry Association(IFA), the Potash and Phosphate Institute, Canada (PPIC),
and International Potash Institute(IPI). 相似文献
66.
双壁钢围堰吸泥下沉、清基及水下封底过程中有关问题的处理办法 总被引:3,自引:0,他引:3
系统概述了介绍芜湖长江大桥11号主墩双壁钢围堰吸泥下沉、清基及水下封底过程和应注意的事项及有关问题的解决办法。 相似文献
67.
弱势高校既是高校中的弱势群体,又是高等教育大众化的主要载体。弱势高校在大众化中迎来了历史性发展机遇,但同时又遇到了后续生源、师资、社会保障、社会关系和自然环境、人文等资源短缺性难题。使其品质提升难以为继,生存发展空间受阻,解决资源短缺困扰,需要社会、政府的支持和经济的发展、社会的进步,但从弱势高校自身来说,必须利用市场和计划,深化改革,更新办学理念,形成办学特色,提高教育质量,加强队伍建设和创新管理机制。 相似文献
68.
In this study, the relationship between latent constructs of phonological awareness (PA) and rapid automatized naming (RAN) were investigated and related to later measures of reading and spelling in children learning to read in different alphabetic writing systems (i.e., Norwegian/Swedish vs. English). 750 U.S./Australian children and 230 Scandinavian children were followed longitudinally between kindergarten and 2nd grade. PA and RAN were measured in kindergarten and Grade 1, while word recognition, phonological decoding, and spelling were measured in kindergarten, Grade 1, and Grade 2. In general, high stability was observed for the various reading and spelling measures, such that little additional variance was left open for PA and RAN. However, results demonstrated that RAN was more related to reading than spelling across orthographies, with the opposite pattern shown for PA. In addition, tests of measurement invariance show that the factor loadings of each observed indicator on the latent PA factor was the same across U.S./Australia and Scandinavia. Similar findings were obtained for RAN. In general, tests of structural invariance show that models of early literacy development are highly transferable across languages. 相似文献
69.
Gizem Hülür Oliver Wilhelm Stefan Schipolowski 《Learning and individual differences》2011,21(6):742-746
We investigated the usefulness of the Over-Claiming Questionnaire (OCQ) as a measure of cognitive abilities. In OCQs respondents are asked to rate their familiarity with items of academic or everyday knowledge (Paulhus, Harms, Bruce, & Lysy, 2003). Some items exist in reality (reals), and others do not (foils). We developed four OCQs, each consisting of 40 reals and 8 foils from the domains of Science, Humanities and Civics. The OCQs were administered in a longitudinal rotation design to 112 participants who attended the 9th school grade at the beginning of the study. In latent variable regression analyses 53% of variation in the reals could be explained by fluid and crystallized intelligence and over-claiming as indicated by responses to foils. Further variation in responses to reals and foils was explained by intellectual engagement. Our results show that self-reported knowledge, although positively related to measures of ability, to a large extent reflects over-claiming. 相似文献
70.
金浩荼油密召事件使一起质量个案演化成了一场公众信用危机.本文从食品召回的现状与不足着手,结合我国有关食品召回的最新立法,对我国食品召回制度提出了一些完善建议. 相似文献