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991.
992.
Quantum chemistry is based on the solution of the Schrödinger equation for a molecule. From starting data on the positions and nature of constituent atoms information is provided about the energy of the molecule and its electronic properties. The former can indicate what shapes drugs can adopt in binding to pharmacological receptors whilst electronic details, when compared using computer graphics, may highlight the factors responsible for biological activity. These techniques are beginning to show real successes in the design of drug molecules. 相似文献
993.
994.
This paper presents a droplet-based microfluidic device for concurrent droplet charging and sorting by electrostatic actuation. Water-in-oil droplets can be charged on generation by synchronized electrostatic actuation. Then, simultaneously, the precharged droplets can be electrostatically steered into any designated laminar streamline, thus they can be sorted into one of multiple sorting channels one by one in a controlled fashion. In this paper, we studied the size dependence of the water droplets under various relative flow rates of water and oil. We demonstrated the concurrent charging and sorting of up to 600 droplets∕s by synchronized electrostatic actuation. Finally, we investigated optimized voltages for stable droplet charging and sorting. This is an essential enabling technology for fast, robust, and multiplexed sorting of microdroplets, and for the droplet-based microfluidic systems. 相似文献
995.
This paper addresses the implementation of technology-forcing policies in open-ended diffusion processes that involve companies and regulators as well as consumers and civil society actors. Mobilising insights from the societal embedding of technology framework and policy steering theories, we investigate two implementation dilemmas that relate to an overarching tension between flexibility (to enable technological learning and stakeholder engagement) and coordinated push (to focus actors and drive deployment): a) early or late formulation of initial targets, and b) technocratic or emergent-adaptive implementation styles. We investigate these dilemmas with four comparative case studies of smart electricity meters between 2000 to 2019, which diffused rapidly in the Netherlands, Norway, and Portugal, but decelerated in the UK. We relate these differences to policy choices, and identify two patterns for successful implementation of technology-forcing policies: a) start with early targets and a technocratic style, but make adjustments if there are substantial protests or technical problems, and b) start with an emergent-adaptive style and formulate and enforce targets later, once technical and social stabilisation has occurred. 相似文献
996.
Kevin H. Ashford-Rowe Marnie Holt 《美中教育评论》2011,(3):317-322
The "emerging educational institutional decision-making matrix" is developed to allow educational institutions to adopt a rigorous and consistent methodology of determining which of the myriad of emerging educational technologies will be the most compelling for the institution, particularly ensuring that it is the educational or pedagogical but not the technological imperative that drives the technology integration agenda. The matrix is designed to be used after some initial research into an emerging technology. Once a technology is put through the matrix, a member of options are available: (1) shelving the technology; (2) putting the technology on hold and maintaining a watching brief until the technology matures in the market; and (3) researching the product further by conducting a trial or placing in testing sandpit. After further research, the technology can be tested as a pilot to determine how well or otherwise, the technology works within the institution. If an emerging technology has more than one product associated with it, a second and third step in the matrix has been developed, and the second step assigns a rating to each of the categories within the matrix. With many products containing similar features, a third step has been developed to compare products on a feature level. 相似文献
997.
998.
An important concern when planning research studies is to obtain maximum precision of an estimate of a treatment effect given a budget constraint. When research designs have a multilevel or hierarchical structure changes in sample size at different levels of the design will impact precision differently. Furthermore, there will typically be differential costs of enrolling additional units at different levels of the hierarchy. The optimal design problem in multilevel research studies involves determining the optimal sample size at each level of the design given specified design parameters and a specified marginal cost of recruitment at each level. The current work extends existing results by considering optimal design for (a) unbalanced random assignment designs and (b) regression discontinuity designs. 相似文献
999.
David H. Johnston 《Cambridge Journal of Education》2016,46(4):533-551
A recent Review of Teacher Education in Scotland reports that 23% of respondents (n = 2381) encountered variable or very poor school placement experiences. This paper uses Lave and Wenger’s ideas concerning Communities of Practice (1998) and Legitimate Peripheral Participation (1991) as analytical tools with which to understand the nature and impact of student teachers’ problematic experiences of school placement. A total of 14 Professional Graduate Diploma in Education students on a one-year Secondary English course were followed through the practice elements of their Initial Teacher Education programme and data were constructed from learning logs and semi-structured interviews. Analysis provided a nuanced account of the student teachers’ difficulties in attaining member status as Legitimate Peripheral Participants in communities of practising teachers, with the concepts ‘joint enterprise’, ‘mutual engagement’ and ‘shared repertoire’ being found to be useful in explaining these difficulties. Limitations in the theoretical framework were also discovered and these are highlighted and developed in the paper. 相似文献
1000.
H. A. Smith J. E. Dyment A. Hill J. Downing 《Journal of Adventure Education & Outdoor Learning》2016,16(4):303-317
This article reports on the experiences of two lecturers working at the University of Tasmania required to teach outdoor and sustainability education (O&SE) courses online. Using an (auto)ethonographic case-study approach, the lecturers were interviewed with a view to exploring their perceptions, challenges, ethical dilemmas, tensions, opportunities and experiences in this space. A number of themes emerged, including commitment to quality teaching and learning, the role of experience, and experiential learning, in the online space, the challenge of fostering a connection to place, difficulties faced when trying to develop a learning community, and the role of professional learning and support in terms of pedagogy and technology in the online space. These themes, and their implications for teaching and learning in higher education both generally, and specifically in O&SE, are discussed in light of what is a mounting body of literature exploring the move to online delivery in higher education. 相似文献