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101.
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Air pollution has a major influence on health. It is thus not surprising that air quality (AQ) increasingly becomes a central issue in the environmental information policy worldwide. The most common way to deliver AQ information is in terms of graphics, tables, pictograms, or color scales that display either the concentrations of the pollutant substances or the corresponding AQ indices. However, all of these presentation modi lack the explanatory dimension; nor can they be easily tailored to the needs of the individual users. MARQUIS is an AQ information generation service that produces user-tailored multilingual bulletins on the major measured and forecasted air pollution substances and their relevance to human health in five European regions. It incorporates modules for the assessment of pollutant time series episodes with respect to their relevance to a given addressee, for planning of the discourse structure of the bulletins and the selection of the adequate presentation mode, and for generation proper. The positive evaluation of the bulletins produced by MARQUIS by users shows that the use of automatic text generation techniques in such a complex and sensitive application is feasible.  相似文献   
103.
A new linear model predictive control (MPC) algorithm in a state-space framework is presented based on the fusion of two past MPC control laws: steady-state optimal MPC (SSOMPC) and Laguerre optimal MPC (LOMPC). The new controller, SSLOMPC, is demonstrated to have improved feasibility, tracking performance and computation time than its predecessors. This is verified in both simulation and practical experimentation on a quadrotor unmanned air vehicle in an indoor motion-capture testbed. The performance of the control law is experimentally compared with proportional-integral-derivative (PID) and linear quadratic regulator (LQR) controllers in an unconstrained square manoeuvre. The use of soft control output and hard control input constraints is also examined in single and dual constrained manoeuvres.  相似文献   
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106.
We present a systematic study on doping of vanadyl- and zinc-pathalocyanine by a fully fluorinated form of tetracyano-quinodimethane as an example of controlled doping of thin organic films by cosublimation of matrix and dopant. The films are characterized in situ by temperature dependent Seebeck and conductivity measurements. We observe a drastic increase of conductivity and a corresponding shift of the Fermi level towards the valence states with increasing dopant concentration. We thus conclude that doping has the potential of both reducing the series resistance and increasing the photovoltage of organic solar cells. As a first step to exploit this potential, we present two different ways of preparing diodes with rectification ratios in excess of 104 using doped phthalocyanines. By adding an undoped interlayer between the contact and the doped layer, we have produced diodes which work already in the strict absence of oxygen and are stable in air. To increase the efficiency of charge carrier generation in photovoltaic cells, we need to use photoactive donor–acceptor-heterojunctions. We present here first examples of pn- and pin-type heterojunctions combining p-doped and nominally undoped layers.  相似文献   
107.
An indium-based seal augmented with an adhesive, developed to maintain a vacuum between two sheets of glass, avoids the high temperatures required to produce a seal in evacuated glazings to date. An experimentally-validated three-dimensional transient model has been used to predict heat transfer for an indium/adhesive sealed 1 m2 area evacuated window with a highly insulating frame. An overall heat loss coefficient of 0.9 W m−2 K−1, with a midplane value of 0.36 W m−2 K−1, can be achieved with 0.72 visible transmittance for two 6 mm panes separated by 0.2 mm diameter pillars 40 mm apart. The conduction through a 3 mm edge-seal was 1.14 W m−2 K−1. Detailed three-dimensional isothermal contour plots through the system are presented.  相似文献   
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109.
This study examined the associations among family processes (cohesion, control, and conflict), school-focused parent–child interactions (support and pressure about achievement), and the child's own characteristics (assertiveness, frustration tolerance, intellectual effectiveness, and self-esteem) as correlates of rule compliance and peer sociability in the classroom. The sample consisted of 161 Grade 4 and 151 Grade 7 children. Family processes and parent-child interactions about school issues were associated with children's personal characteristics, which, in turn, predicted children's rule compliance and peer sociability. Some differences were found between the 4th- and 7th-grade samples; however, many variables consistently predicted the same outcomes across grades. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
Concentrations of ergosterol as low as 1.2 mM are effective in satisfying the essential high specificity microrequirement for C5,6 unsaturated sterol in yeast. In a sterol auxotroph supplemented with saturated sterol (cholestanol), aqueous extracts of yeast provide a growth factor that eliminates the ergosterol microrequirement. The factor is easily differentiated from ergosterol by solubility, thermostability, and thin layer and liquid chromatography and is functional at levels equivalent to those of vitamins, hormones and pheromones.  相似文献   
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