高速PCB中过孔引起的同步开关噪声抑制研究     

刘永勤 《渭南师范学院学报》2011,(12):42-45

高速PCB中，由于过孔数量较多导致信号产生严重畸变．文章首先分析了过孔对高速信号质量的影响，然后通过在过孔周围添加去耦电容器来抑制同步开关噪声（SSN）．结果表明，在过孔周围添加去耦电容器可以有效地减小同步开关噪声，使得信号波动峰值减小，提高了信号质量．  相似文献   

Juggling competing activities: academic staff as doctoral candidates     

Jan Smith  Jennie Billot  Lynn Clouder  Virginia King 《高等教育研究与发展》2020,39(3):591-605

ABSTRACT

This article explores the experiences of a group of established academic staff in New Zealand and the UK, as they undertake a doctorate in their home institutions. Our interest is in how individuals negotiate this dual status from a cultural-historical activity theory (CHAT) stance that explores how rules, tools, community and divisions of labour, and interacting activity systems, shape doctoral experiences. The focus in this article, having analysed their detailed narrative accounts, is on how academics experience three interdependent activity systems: those surrounding the thesis, the institutional context, and the home-life spheres. Issues related to time, workload and supervision issues, variability in collegial support and impact on personal priorities and time emerged. There is a range of particularities – from easy access to resources/supervisors to inflexible institutional regulations – applicable to this group of doctoral candidates. Negotiating life as an academic with concurrent doctoral candidature provides positive outcomes in terms of teaching, research confidence and general personal and professional development. However, a range of difficulties can also be encountered, particularly in relation to personal and professional relationships, and workload management.  相似文献   

用经验模式分解和重标极差分析法进行摩擦振动信号分析     

李精明  魏海军  梅立强  许德志 《上海海事大学学报》2016,37(2):89-93

为提取和表征摩擦振动的特征信号，在摩擦磨损试验机上进行以船用柴油机缸套和活塞环为材质的摩擦副摩擦磨损试验.应用经验模式分解(Empirical Mode Decomposition, EMD)对非线性、非平稳的摩擦振动信号进行分解，获得若干个本征模式函数(Intrinsic Mode Function, IMF).从中选择反映摩擦振动特征的IMF重新合成摩擦振动特征信号，应用重标极差分析法对摩擦振动特征信号进行分析，得到线性回归谱和Hurst指数.结果表明，EMD能够实现摩擦振动特征信号的提取，重标极差分析法可以分析摩擦振动信号的渐变过程，提取摩擦振动信号的特征.该方法可为基于摩擦振动信号的机械摩擦副摩擦磨损行为的研究提供新的途径.  相似文献   

多媒体阅览室拓展少儿网络学习教育功能的思考——以柳州市图书馆多媒体阅览室为例     

韦志凡 《柳州师专学报》2011,26(3):138-140

互联网承载和传播着大量的信息和数据,其中有不少涉及色情、暴力、诈骗等不健康信息。以柳州市图书馆多媒体阅览室为例,就如何正确引导少儿读者利用网络进行学习,拓展公共图书馆多媒体阅览室的网络学习教育功能阐述了自己的想法。  相似文献   

谈高职院校计算机专业毕业论文（设计）的改革     

曹福德 《山东商业职业技术学院学报》2011,11(4):54-57

当前,我国高校毕业论文（设计）存在抄袭、拼凑成风的不良现象,结合高职院校计算机专业毕业论文指导工作的现实情况,有针对性地提出了基于工作过程的改革方法,在实践中让学生自主选题,形式上不拘一格,并且规范写作与指导流程,使得毕业论文（设计）真正地为学生服务。  相似文献   

第31届奥运会男篮参赛球队攻防能力研究          下载免费PDF全文

金超 《河北体育学院学报》2017,31(3):63-70

采用文献资料法、录像观察法和秩和比法等,对参加31届奥运会男篮比赛球队的攻防能力进行综合量化评价,并将中国男篮与对手的攻防能力指标进行对比分析.结果显示:中国男篮进攻RSR处于D级,在得分、助攻、3分球命中率与罚球命中率上,与对手存在非常显著性差异,在失误数、进攻篮板、3分球出手数上与对手存在显著性差异;中国男篮防守RSR处于D级,防守篮板数比对手少,而失分和犯规数比对手多,且在犯规数上与法国男篮存在显著性差异;中国男篮攻防RSR处于E级;球队最终排名与进攻RSR值和攻防RSR值之间存在非常显著性相关.  相似文献   

Tinkering through transition: on ‘doctoring’ as an early-career academic in physical education and sport pedagogy     

Benjamin Williams  Erin Christensen  Joseph Occhino 《Sport, Education and Society》2017,22(1):73-86

This article addresses the notion of ‘making it’ as an early-career academic in physical education and sport pedagogy. In it, we draw on the tradition of material semiotics to reflect on our shared journeys from doctoral student to beginning scholar and beyond. By attuning ourselves to the relationality, materiality and precariousness of our experiences, we offer an answer to the question of what it takes to ‘make it’ as an early-career academic by advocating the practice of ‘making do’ or ‘doctoring.’ We develop this argument, first, by describing the narrative methods we used to conduct our inquiry and by explaining the material-semiotic ideas we used to explore the stories it generated. Then, we tell tales of our transitions from higher degree research student to early-career academic, focusing specifically on our ongoing, collective efforts to make do. In our discussion, we explore these narratives and attend to three features of our actions and activities as early-career academics; namely semiotic relationality, material heterogeneity and the precarious processes of heterogeneous engineering through which we sought to make a career in our field. We conclude by encouraging beginning scholars in physical education and sport pedagogy to become sensitive to these aspects of their own agency, and to experiment, experience and tinker together in ways that are attentive, inventive, caring and persistent.  相似文献   

澳大利亚国家图书馆展览政策研究   总被引：1，自引：0，他引：1  

李剑 《图书情报工作》2019,63(13):137-144

[目的/意义]国内图书馆对展览政策的研究较少，而国外图书馆在相关领域有比较成熟的做法。研究国外图书馆展览政策有助于促进国内图书馆展览工作的开展。[方法/过程]通过对澳大利亚国家图书馆展览政策与展品租借政策文本的梳理与研究，探索其有益做法对我国图书馆的启示。[结果/结论]我国图书馆应从4方面完善展览工作：①重视展览工作的组织建设；②重视对展览原则的研究；③结合国家文物保护政策制定展品借出政策；④结合我国实际制定展品借入政策。  相似文献   

Influence of Cultural Orientations on Electronic Word-of-Mouth (eWOM) in Social Media     

Youngtae Choi 《Journal of Intercultural Communication Research》2019,48(3):292-313

This study explores how horizontal/vertical individualism and collectivism (HVIC) orientations influence electronic word-of-mouth (eWOM) (i.e., opinion leadership and opinion seeking) in social media. Online survey panel data through Amazon MTurk were collected from American social media users to address the research purpose. The results, using the structural equation modeling, show that the paths from horizontal individualism to opinion leadership, vertical individualism to opinion leadership and opinion seeking, horizontal collectivism to opinion leadership, and vertical collectivism to opinion leadership and opinion seeking were significant. This study provides theoretical and managerial implications regarding the influence of HVIC orientations on eWOM in social media.  相似文献   

The Saljuq Turks’ Conversion to Islam: The Crusading Sources     

Nicholas Morton 《Al-Masaq: Islam & the Medieval Mediterranean》2015,27(2):109-118

This article contributes to the important debate over the conversion of the Turks to Islam. Previously, it was thought that the Turks abandoned their former steppe faith and customs very swiftly to become staunch Sunni Muslims, but this view has recently been challenged by a number of studies. The current consensus seems to be that the Turks’ adoption of Islam was a process of far longer duration, spanning many decades. This article broadens this discussion by demonstrating that the chronicles written by the First Crusaders contain much useful information that is pertinent to this question. It works through these texts, showing that they can shed new light on this point.  相似文献