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21.
高分子物理是高分子材料相关专业的专业基础课,内容丰富,章节间关系复杂,课程主线往往不容易把握。本文从运动对高聚物性质(性能)的决定性作用角度,提出了构建高分子物理课程知识体系的观点:在高分子结构部分,充实原子、键等部分作用的论述,完善高分子结构划分的层次;明确高分子不同结构层次都具有运动与变化能力的认知,重点突出不同高分子结构运动、变化的特征和规律;根据根据每一个结构层次运动特征,综合理解结构、结构的变化对高分子性能的影响。 相似文献
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We define the emerging research field of applied data science as the knowledge discovery process in which analytic systems are designed and evaluated to improve the daily practices of domain experts. We investigate adaptive analytic systems as a novel research perspective of the three intertwining aspects within the knowledge discovery process in healthcare: domain and data understanding for physician- and patient-centric healthcare, data preprocessing and modelling using natural language processing and (big) data analytic techniques, and model evaluation and knowledge deployment through information infrastructures. We align these knowledge discovery aspects with the design science research steps of problem investigation, treatment design, and treatment validation, respectively. We note that the adaptive component in healthcare system prototypes may translate to data-driven personalisation aspects including personalised medicine. We explore how applied data science for patient-centric healthcare can thus empower physicians and patients to more effectively and efficiently improve healthcare. We propose meta-algorithmic modelling as a solution-oriented design science research framework in alignment with the knowledge discovery process to address the three key dilemmas in the emerging “post-algorithmic era” of data science: depth versus breadth, selection versus configuration, and accuracy versus transparency. 相似文献
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Internet technologies are increasingly being used within all knowledge management processes, including knowledge acquisition, knowledge exchange and knowledge use. Although technological issues are key drivers for Internet technologies adoption and use, organizational and environmental aspects have been found to be equally important. This paper extends previous studies on the use of Internet technologies and knowledge management by analyzing factors affecting Web knowledge exchange in small and medium-sized enterprises (SMEs). More specifically, by drawing on the technology–organization–environment framework, a model to examine how distinct contextual factors influence Web knowledge exchange in SMEs is developed. The hypotheses are tested by using structural equation modelling on a large sample of Spanish SMEs from different industries. Results suggest that IT expertise and commitment-based human resource practices positively affect Web knowledge exchange, with the latter being the strongest factor in our proposed model. In contrast, a negative relationship is found between competition and Web knowledge exchange. 相似文献
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Maria Elizabeth Grabe Ozen Bas Irene Ingeborg van Driel 《The Journal of communication》2015,65(2):300-319
Education‐based knowledge gaps are well‐documented across countries, media platforms, and content. Without exception, knowledge is measured through words not images. Given the centrality of sight in the natural history of Homo sapiens, the extraordinary visual acuity of humans, and the proliferation of screen‐based visual media environments in contemporary life, an experiment was conducted to test the knowledge gap visually. Participants watched 8 audiovisual news stories. Simple recognition of story details and comprehension of that information were tested in verbal and visual modalities. Results offered the first confirmation of the knowledge gap in visual terms. Yet, gaps were significantly smaller employing visual than verbal measures, pointing to the need for continued efforts to develop visual measures for future memory studies. 相似文献
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Media as Educator,Media as Disruptor: Conceptualizing the Role of Social Context in Media Effects
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We document how social contexts serve to refract media effects. We theorized the relationship between media use and individual‐level knowledge (and attitude) would be stronger when community‐level knowledge (and attitude) was low than when it was high. Data come from a national survey (N = 12,608 women and 1,237 men) conducted in Nepal. Knowledge and stigma toward people living with HIV were the 2 dependent variables. Hypotheses were tested 12 times: across the use of 3 media (newspaper, radio, television) × 2 study outcomes (knowledge and attitudes) × 2 genders. Predicted interactions were supported in 9 of the 12 tests. Findings point to the need to take into account the role of community factors in theorizing about media effects. 相似文献
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When constructing Bayesian networks with domain experts, network engineers often use the noisy-OR model, and causal interaction models more generally, to alleviate the burden of probability elicitation: the use of such a model serves to reduce the number of probabilities to be elicited on the one hand, and on the other hand forestalls experts having to give assessments for probabilities with compound conditions which they feel are hard to envision. Recently, we have shown that ill-considered use of the noisy-OR model specifically can substantially decrease a network's performance, especially in domains in which causal mechanisms include cancellation effects. Motivated by this observation, we designed a new causal interaction model, with the same engineering advantages as the noisy-OR model, to describe such effects. We detail properties of our intercausal cancellation model, and compare it against existing causal interaction models. We further illustrate the application of our model in the real-world domain of pharmacology. 相似文献
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简述了二维立体显示的现状,分析了真三维立体显示静态成像技术的基本原理和成像空间材料选取的依据,给出了真三维立体显示系统的控制模型,最后以人体心脏为例实现了真三维立体显示静态成像的模拟,并列举了它在各领域中的应用。 相似文献
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Given two rooted, labeled trees P and T the tree path subsequence problem is to determine which paths in P are subsequences of which paths in T. Here a path begins at the root and ends at a leaf. In this paper we propose this problem as a useful query primitive for XML data, and provide new algorithms improving the previously best known time and space bounds. 相似文献