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151.
Future Scenarios: What are the Future Services and Applications?   总被引:1,自引:1,他引:0  
With the change of paradigm within user-machine interaction, there is an increasing demand for seamless interoperability between different technologies as well as more intuitive ways of utilizing the applications on the devices. This implies that the underlying technologies must support the appropriate bandwidth, mobility and quality at the right cost in order for the end-user to perceive the infrastructure appropriate for the services and corresponding applications of the future. In addition, it is required that interoperability will be realized at the semantic level and not just the syntactical level. The purpose of the paper is to present the authors’ thoughts of a new Information and Communication Technology paradigm and to highlight what might have an impact on the realization/deployment of such a paradigm.  相似文献   
152.
153.
Personality and social relationships were assessed twice across a 4-year period in a general population sample of 489 German young adults. Two kinds of personality–relationship transaction were observed. First, mean-level change in personality toward maturity (e.g., increase in Conscientiousness and decrease in Neuroticism) was moderated by the transition to partnership but was independent of other developmental transitions. Second, individual differences in personality traits predicted social relationships much better than vice versa. Specifically, once initial correlations were controlled for, Extraversion, Shyness, Neuroticism, self-esteem, and Agreeableness predicted change in various qualities of relationships (especially with friends and colleagues), whereas only quality of relationships with preschool children predicted later Extraversion and Neuroticism. Consequences for the transactional view of personality in young adulthood are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
154.
Optimization models for operative planning in drinking water networks   总被引:1,自引:0,他引:1  
The topic of this paper is minimum cost operative planning of pressurized water supply networks over a finite horizon and under reliable demand forecast. Since this is a very hard problem, it is desirable to employ sophisticated mathematical algorithms, which in turn calls for carefully designed models with suitable properties. The paper develops a nonlinear mixed integer model and a nonlinear programming model with favorable properties for gradient-based optimization methods, based on smooth component models for the network elements. In combination with further nonlinear programming techniques (Burgschweiger et al. in ZIB Report ZR-05-31, Zuse Institute Berlin, 2005), practically satisfactory near-optimum solutions even for large networks can be generated in acceptable time using standard optimization software on a PC workstation. Such an optimization system is in operation at Berliner Wasserbetriebe.  相似文献   
155.
Blends of organic electron and hole conductive materials are widely used for ambipolar charge carrier transport and photovoltaic cells. An obvious choice for donor–acceptor blends are organic semiconducting materials in their hydrogenated and fluorinated form, since they combine potentially suitable electronic properties with structural compatibility of the two constituents. This study focuses on the structural, optical, and electrical properties of blends using hydrogenated copper-phthalocyanine (H16CuPc) in combination with its per-fluorinated version (F16CuPc). Using X-ray scattering, scanning force microscopy and optical absorption measurements we show that mixed crystalline films are obtained by co-evaporation of the two materials. Electrical transport measurements reveal a profound reduction of the current for bipolar charge injection in mixed films. We discuss the formation of self-trapped charge transfer excitons as possible explanation for this unexpected behaviour, which impedes the usability of this system in photovoltaic cells.  相似文献   
156.
Recent progress in ellipsometry instrumentation permits precise measurement and characterization of optical coating materials in the deep-UV wavelength range. Dielectric coating materials exhibit their first electronic interband transition in this spectral range. The Tauc-Lorentz model is a powerful tool with which to parameterize interband absorption above the band edge. The application of this model for the parameterization of the optical absorption of TiO2, Ta2O5, HfO2, Al2O3, and LaF3 thin-film materials is described.  相似文献   
157.
Miniature cylindrical ion trap mass spectrometer   总被引:4,自引:0,他引:4  
A miniature cylindrical ion trap mass spectrometer is described, and preliminary data are presented. Functionality and performance of laboratory-scale instruments have been maintained to the extent possible in this battery-operated mass spectrometer. Capabilities include tandem mass spectrometry experiments. Custom-designed electronic components include the RF scanning and amplification system, data acquisition components, and lens power supplies, as well as a custom-software application. Direct leak and membrane introduction inlet systems are used for sample introduction. A mass/charge range of approximately 250 Th with unit mass resolution has been demonstrated.  相似文献   
158.
Nitric oxide and myoglobins   总被引:1,自引:0,他引:1  
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159.
160.
We show that the NP-complete Feedback Vertex Set problem, which asks for the smallest set of vertices to remove from a graph to destroy all cycles, is deterministically solvable in O(ckm) time. Here, m denotes the number of graph edges, k denotes the size of the feedback vertex set searched for, and c is a constant. We extend this to an algorithm enumerating all solutions in O(dkm) time for a (larger) constant d. As a further result, we present a fixed-parameter algorithm with runtime O(k2m2) for the NP-complete Edge Bipartization problem, which asks for at most k edges to remove from a graph to make it bipartite.  相似文献   
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