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991.
用化学还原法制备了非晶态合金催化剂Ni-B、Co-B和Co-Ni-B.合金的非晶性质由X射线衍射(XRD)及透射电子显微镜(TEM)鉴定.组成用电感耦合等离子发射光谱(ICP)分析.在高真空程序升温脱附质谱(TPD-MS)装置上研究了CO、H2在三种催化剂上的吸附及CO和H2的表面反应(TPSR).发现CO和H2在三种催化剂上分别有二种和一种吸附态,吸附强度和二种吸附态的数目在不同合金上有较大差异.CO加氢反应的主要产物是CH4、CO2和H2O,其中CO在催化剂表面上的解离是反应的控制步骤. 相似文献
992.
993.
This study aims to investigate the effects of relative advantage, complexity, upper management support, cost, market dynamics, competitive pressure and regulatory support on blockchain adoption for operations and supply chain management among Small-Medium Enterprises (SMEs) in Malaysia. Unlike existing studies that employed linear models with Technology Acceptance Model or United Theory of Acceptance and Use of Technology that ignores the organisational and environmental factors, we adopted the Technology, Organisation and Environment Framework that covers the technological dimensions of relative advantage and complexity, organisational dimensions of upper management support and cost and environmental dimensions of market dynamics, competitive pressure and regulatory support. Empirical data from 194 SMEs were investigated and ranked using a nonlinear non-compensatory PLS-ANN approach. Competitive pressure, complexity, cost and relative have significant effects on behavioural intention. Market dynamics, regulatory support and upper management support were insignificant predictors. SMEs often lack resources for technological investments but faces same requirements for streamlining business processes to optimise returns and blockchain presents a viable option for SMEs’ sustainability due to its features of immutability, transparency and security that have the potential to revolutionise businesses. This study contributes new knowledge to the literature on factors that affect blockchain adoption and justifications were discussed accordingly. 相似文献
994.
为更好地提高现有轮机模拟器实操评分的准确性,参考国内轮机模拟器自动评分系统的原理,提出一种多级模糊综合评价方法。该方法依据中华人民共和国海事局在《海船船员适任考试与评估大纲》中规定的实操技能要求,建立评价指标体系。使用层次分析法(analytic hierarchy process,AHP)确定各指标权重,选择适宜的隶属度函数模型确定各指标的隶属度。实时采集船员在实操训练过程中产生的数据,依据专家系统进行模糊评价。经专家验证取得了理想的结果。模型提高了实操评分的准确性、公正性及其评价效率,可为海事部门的考核提供有力的支撑。 相似文献
995.
Paul Michael Greenhouse 《Educational Psychology in Practice》2013,29(4):404-415
This article discusses the quality of professional relationships between educational psychologists (EPs) and other professionals who work around children, young people and their families as part of a multi-agency team (MAT). The perceived barriers to, and facilitators of, effective multi-agency working are explored in relation to their potential impact upon the process of engaging service users in change. The actions that take place within a MAT are analysed from the systemic perspective of sociocultural activity theory (AT), and supported by examples drawn from behaviour and education support teams (BESTs). The implications for professional practice are discussed. 相似文献
996.
ABSTRACTThe 2015–2016 South African higher education students’ movement proved historical for our country in bringing to our dinner tables: issues of higher education transformation and decolonisation; institutional culture(s); curriculum reform; the need to foreground and make inclusive assessment in education; the coloniality in our knowledge production, and more. Influenced by the emergence of the student movements and the critique they have brought to South African higher education, we bring to the fore the often silent critical reflections on the purposes of higher education in general, and in South Africa especially, as they relate to teaching and learning. We propose that the purposes of higher education in relation to teaching and learning ought to respond to (1) context, (2) democratic difference, and (3) cosmopolitan perspectives. We argue that discourses, phases and logics about South African higher education have tended to disregard and, at times, blur the context and differences as well as cosmopolitan perspectives. Using the notion of Ubuntu-Currere, we re-imagine how teaching and learning could respond to context, difference and cosmopolitanism with examples from the South African higher education experience. 相似文献
997.
数字图书馆像其他新技术一样,其能否有效使用依托于用户对它的接受度,同时这种接受度又会受到用户对系统易用性认识的影响。新技术的引进应用往往包含某种针对用户的变化,而最近针对阻碍个性变革的现象的发现,以及对其一系列的测评方法的产生,为客观评定阻碍数字图书馆系统变革和对新用户的影响,提供了一个很好的分析平台。以往有研究将个性差异与系统特性作为影响认知易用性的因素,根据这类研究,他们发现阻碍变革不仅是决定认知易用性的一个非常重要的因素,而且会提高对过去技术接受模式的阐释力。 相似文献
998.
为对船舶航行安全状况进行有效预测,利用支持向量回归(support vector regression, SVR)算法构建船舶航行安全评估模型。在分析影响船舶航行安全的因素的基础上,对船舶历史数据进行预处理后将其作为模型训练和测试的样本数据。实验结果表明:该模型评估准确度可达99.6%以上;在同一样本数据条件下,模型的评估准确度和稳定性均优于基于极限学习机(extreme learning machine,ELM)构建的模型。模型的评估结果为水上交通管理部门的监管提供参考。 相似文献
999.
采用问卷法对国内高校252位大学生受试者进行了ou(gh)语音偏误调查,结果显示,英语作为外语教学中语音偏误率大致与词频成反比分布。造成偏误原因有词频、文言不一、缺乏历史音韵学知识等。音变规律的掌握及设计符合认知规律的词频分布阅读材料可有效减少这一偏误。 相似文献
1000.
本文利用灰色系统中的GM(1,1)模型,得到了关于我国废水排放量的一个较为精确的预测模型并加以应用,为进行决策与制定计划提供一个很好的帮助,利于改善我国的水环境。 相似文献