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351.
We present a simple technique for creating an on-chip magnetic particle conveyor based on exchange-biased permalloy microstripes. The particle transportation relies on an array of stripes with a spacing smaller than their width in conjunction with a periodic sequence of four different externally applied magnetic fields. We demonstrate the controlled transportation of a large population of particles over several millimeters of distance as well as the spatial separation of two populations of magnetic particles with different magnetophoretic mobilities. The technique can be used for the controlled selective manipulation and separation of magnetically labelled species. 相似文献
352.
‘The answer to the machine is in the machine’ – but what is the answer? At the end of the first decade of the 21st century we are seeing an explosion of rights management issues, as well as the emergence of many products and services that may provide all – or at least some – of the solution for publishers. International standards are also in place. Strong intellectual property protection is the cornerstone of an orderly digital marketplace. That market is for content + rights. Are our rights management practices fit for purpose? In this paper we provide an overview of rights management in publishing at the start of the 21st century, a summary of what is at stake, and an overview of the challenges and opportunities that await publishers. 相似文献
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Steen Beck Dion Russelbaek Hansen 《美中教育评论》2009,6(8):1-16
Danish upper-secondary school is currently undergoing remarkable changes. Comprehensive reforms and restructuring have transformed teacher roles and school organization. However, not all upper-secondary teachers welcome reform: on the one hand, they have to adopt norms, standards and values determined by colleagues, if they want to "fit in"; on the other hand, they are confronted by governmental and educational claims, but also their own interest in doing things differently. This paper analyzes generational differences and similarities in the post-reform school in regard to leaming values and the competence discourse, which are an important part of the reform discourse. In addition, it explores the dilemmas which arise for young teachers their understanding of practical and theoretical teacher training. This paper combines theoretical approaches with data analysis being both quantitative and qualitative. Finally, this paper discusses team work as an important means to make dialogue between teacher generations possible and to enhance reflection on the relationship between practice and theory. 相似文献
358.
The Bologna Process in Europe aims to develop a coherent and compatible European higher educational system. In Norway, the
Quality Reform in 2003 was the first step on implementing the Bologna Process. Internal quality assurance systems have produced
several publications on internal indicators, such as student progress and teaching staff work loads, of the Quality Reform.
To our knowledge, possible gender differences of these changes have yet to be evaluated. We therefore analyzed data on grades
from the University of Oslo before and after the Quality Reform with regard to gender differences. Data on examinations from
1990 to spring 2007 (495,334 examinations) were analyzed using relative percentage graphs. The results show that female students
have benefited more than males from the change of system: for several disciplines, male average grades were better than female
average grades before the change, and female average grade were better than male average grades after the change. Male students
show greater intrasex variability both before and after the introduction of the Quality Reform. 相似文献
359.
Markus Grillitsch Teis Hansen Lars Coenen Johan Miörner Jerker Moodysson 《Research Policy》2019,48(4):1048-1061
The orientation towards grand societal challenges can be seen as a new wave or paradigm for innovation policy. Such policy aims at system-wide transformation and is often referred to as system innovation policy. While insights from transition studies have provided novel and useful rationales for innovation policy targeting system-wide transformation, it remains unclear how to design, implement and evaluate such policies. The contribution of this paper is to translate and concretize the challenges of system innovation policy towards scope for policy action and analysis. Building on insights from transition studies we group the challenges into four domains: directionality, experimentation, demand articulation, and policy coordination and learning. We relate challenges within the four domains to three generic features of innovation systems: interests and capabilities of actors, networks, and institutions. The derived framework is applied in a case study on the strategic innovation programmes, a recent policy initiative by Vinnova, Sweden’s Innovation Agency, targeting system innovation. 相似文献
360.
How do intellectual propriety rights (IPRs) help firms profit from their innovation? Innovation literature frequently turns to patents to measure innovative IPR, but more recent work shifts focus to the other side of IPR, namely, trademarks. This article therefore discusses the effects of trademark strategies when companies decide to introduce their product portfolios in a new foreign market. Entrants might opt for a common trademark across different country markets (integration) or use several country-specific trademarks (responsiveness). This empirical study exploits the quasi-natural experiment created by the tariff shock that affected Spain when it joined the European Union in the 1990s. Data from the automotive industry reveal how non-European companies that already operated in other European countries sought to enter Spain rapidly, using various trademark strategies. The product portfolio characteristics are fixed at entry, so this study can specify how and when trademark responsiveness versus integration affects firm performance. The results reveal that trademark responsiveness increases firm performance if the firms suffer high liabilities of foreignness or newness. 相似文献