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Gelinck GH Huitema HE van Veenendaal E Cantatore E Schrijnemakers L van der Putten JB Geuns TC Beenhakkers M Giesbers JB Huisman BH Meijer EJ Benito EM Touwslager FJ Marsman AW van Rens BJ de Leeuw DM 《Nature materials》2004,3(2):106-110
At present, flexible displays are an important focus of research. Further development of large, flexible displays requires a cost-effective manufacturing process for the active-matrix backplane, which contains one transistor per pixel. One way to further reduce costs is to integrate (part of) the display drive circuitry, such as row shift registers, directly on the display substrate. Here, we demonstrate flexible active-matrix monochrome electrophoretic displays based on solution-processed organic transistors on 25-microm-thick polyimide substrates. The displays can be bent to a radius of 1 cm without significant loss in performance. Using the same process flow we prepared row shift registers. With 1,888 transistors, these are the largest organic integrated circuits reported to date. More importantly, the operating frequency of 5 kHz is sufficiently high to allow integration with the display operating at video speed. This work therefore represents a major step towards 'system-on-plastic'. 相似文献
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A cross-sectional study was performed in eight companies, comprising 32 buildings without previously recognized indoor air problems. Engineers filled in a technical questionnaire on building characteristics, floor surface materials, ventilation, cleaning procedures, heating and cooling. A total of 3562 employees returned questionnaires on individual factors, workload, perceived physical work environment, allergy and symptoms. Frequent symptoms were feeling of fatigue or heavy-headedness, eye irritation, and dry facial skin. Women reported symptoms more frequently than men. Employees with allergy had a 1.8-2.5 times risk of reporting a high score for general, skin, or mucosal symptoms. The risk of a high symptom score increased with daily visual display unit (VDU) work time. Passive smoking and psychosocial load were also relatively strong predictors of symptoms. Weekly cleaning as compared with a frequency of cleaning two to four times a week increased the risk of symptoms. Adjusted odds ratio for a high general symptoms score from infrequent cleaning was 1.5 (95%CI 1.1-2.0). A high ventilation flow or central ventilation unit filter EU7 vs. EU8 seemed to be associated with an increased risk of general symptoms. Absence of local temperature control increased the risk of mucosal symptoms. 相似文献
44.
Dealloying of Au-Ag thin films with a composition gradient: Influence on morphology of nanoporous Au 总被引:1,自引:0,他引:1
Nanoporous Au can be formed by dealloying Au-Ag alloys and, depending on the initial alloy composition, produce a variety of microstructural features. We investigated a wide compositional range and found three regimes, based on initial Au content, that yield varying degrees of dealloying in thin films. Between 22 and 26 at.% Au, dealloying produces nearly pure Au with an open nanoporous structure. However, above 36 at.% Au, only the grain boundaries dealloy, leaving islands of retained Au-Ag alloy. For intermediate compositions, a transitional microstructure results, with final Ag concentration ranging from 50 at.% down to 4 at.%. Film cracking was observed after dealloying, and lower initial Au content correlated with a higher degree of cracking and a higher pore fraction. 相似文献
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We show that the sup-t-norm and inf-residuum types of fuzzy relational equations, considered in the literature as two different types, are in fact two particular instances of a single, more general type of equations. We demonstrate that several pairs of corresponding results on the sup-t-norm and inf-residuum types of equations are simple consequences of single results regarding the more general type of equations. We also show that the new type of equations subsumes other types of equations such as equations with constraints on solutions, examples of which are fuzzy relational equations whose solutions are required to be crisp (ordinary) relations. 相似文献
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We present uniform asymptotic solutions (UAS) for displacement discontinuities (DD) that lie within the middle layer of a three layer elastic medium. The DDs are assumed to be normal to the two parallel interfaces between the leastic media, and solutions will be presented for both 2D and 3D elastic media. Using the Fourier transform (FT) method we construct the leading term in the asymptotic expansion for the spectral coefficient functions for a DD in a three layer medium. Although a closed form solution will require an infinite series solution, we demonstrate how this UAS can be used to construct highly efficient and accurate solutions even in the case in which the DD actually touches the interface. We present an explicit UAS for elements in which the DD fields are assumed to be piecewise constant throughout a line segment in 2D and a rectangular element in 3D. We demonstrate the usefulness of this UAS by providing a number of examples in which the UAS is used to solve problems in which cracks just touch or cross an interface. The accuracy and efficiency of the algorithm is demonstrated and compared with other numerical methods such as the finite element method and the boudary integral method. 相似文献
49.
Much research has been done on sorting networks but there are very few results concerning their robustness. Our starting point is the balanced sorting network introduced by Dowd et al. and its single-block robust design of Rudolph obtained at the cost of some redundancy and two permuters external to the network. In this article we introduce a new implementation which is more robust than Rudolph's network and needs no redundancy or external permuters. We also consider a class of single-stage designs with redundancy and compare the characteristics of networks discussed. 相似文献
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