Aspects of decision support in water management--example Berlin and Potsdam (Germany) I--spatially differentiated evaluation

Decisions about sustainable development demand spatially differentiated evaluations. As an example, we demonstrate the evaluation of water management strategies in the cities of Berlin and Potsdam (Germany) with respect to their ecological effects in 14 sections of the surface water system. Two decision support systems were compared, namely PROMETHEE, which is designed to obtain a clear decision (linear ranking), and Hasse Diagram Technique (HDT), normally providing more than one favourable solution (partial order). By PROMETHEE, the spatial differentiation had unwanted effects on the result, negating the stakeholders determined weighting of indicators. Therefore, the stakeholder can barely benefit from the convenience of obtaining a clear decision (linear ranking). In contrast, the result obtained by HDT was not influenced by spatial differentiation. Furthermore, HDT provided helpful tools to analyse the evaluation result, such as the concept of antagonistic indicators to discover conflicts in the evaluation process.     

Thermodynamic analysis of the melting equilibria in the iron-silicon system

Published experimental values for the thermochemical properties and phase boundaries of iron-silicon alloys have been evaluated so as to provide consistency. The resulting self-consistent set of data has been used to calculate the phase diagram in agreement with the experimental results.     

Grain Size Dependence of Electrical Conductivity in Polycrystalline Cerium Oxide

The magnitude and activation energy of electrical conductivity in nanocrystalline cerium oxide exhibit a clear grain size dependence. Experimental results compiled from the literature were analyzed using a space charge model, which takes into account the deviation of point defect concentrations from their bulk values in the vicinity of grain boundaries. The consequences on conductivity arising from such space charge layers were calculated using the brick-layer model (BLM) for grain sizes L large compared to the screening length . The obtained results were supplemented by the calculated conductivity in the flat-band limit for L . This combination allowed for a quantitative comparison with experimental values, which were obtained in the mesoscopic regime of grain sizes from 10–40 nm. The analysis yielded a value for the space charge potential in cerium oxide of 0.55 V. This space charge potential is caused by a reduced standard chemical potential of oxygen vacancies in the grain boundary core as compared to the bulk phase.     

On the expression and experience of surprise: No evidence for facial feedback, but evidence for a reverse self-inference effect.

Three studies examined the effects of experimentally manipulated surprise expressions on the experience of surprise. Surprise was induced by a sudden, unannounced change of the stimulus presentation during a computerized task. Facial expression was manipulated by leading participants to adopt an expression akin to surprise, or by forcing them to look up steeply to a monitor. The expression manipulations had no intensifying effect on the experience of surprise, whereas manipulations of unexpectedness and mental load had strong effects. In addition, mental load was found to affect beliefs about facial expression, suggesting that the participants used their feelings of surprise to infer their probable facial displays. Path analyses supported this reverse self-inference hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A parameterization of reduced stable models and controllers

This note addresses the problem of instability in both model and controller reduction methods based on similarity transformations. For a given model (controller) a general framework is proposed that parameterizes a large set of reduced models (controllers) that preserve the stability of the original model (closed loop system). In addition, a sufficient condition for the existence of such a framework is derived. As an application of the main results, it is shown how different reduction methods can be modified, if they fail to maintain stability.     

Deriving fine-scale socioeconomic information of urban areas using very high-resolution satellite imagery

This article presents a new approach to derive fine-scale socioeconomic information of urban areas using very high resolution satellite data. The rationale behind the method is to use high resolution satellite data, capable of resolving urban morphology details, to derive a classification of the image. Thus, it is assumed that there is a relationship between the socioeconomic profile and the urban morphology of an area in terms of availability of green areas, sport facilities, private swimming pools or pavement conditions. The method is tested using a case study of Lima, Peru. Using a sample of ground data, a neural network classifier was applied to a pre-classified image in which entropy had been used to mask extensive, non-built up areas that would otherwise have inserted spurious information into the classifier. The result shows a high correlation (0.70 R ²) when compared with validation data. The good performances also show that a physiographic satellite view of the city reflects the socioeconomic layout of their inhabitants, thus making remote sensing a complementary tool for social research and urban planning. While the parameterization of the problem may differ from one area to another, it is shown that an a priori choice of a few parameters may help to automatically characterize large areas in social terms, thus allowing social inequality and its evolution to be mapped in those areas with limited availability of data. In order to make the method widely applicable, the possibilities and limitations of applying the procedure to other large cities are discussed.     

Temperature dependence ofH c2 andк 1 in strong coupling superconductors

According to the law of corresponding states, the properly scaled critical fields of a BCS superconductor are universal functions of the reduced temperatureT/T _c . In realistic superconductors strong-coupling effects can cause deviations from this universal behavior. We present numerical results for the strong-coupling anomalies in the temperature dependence of the upper critical fieldH _c2 and the Ginzburg-Landau parameter κ₁. The calculations are based on the Eliashberg theory for strong-coupling superconductors and are performed for several realistic superconductors as well as for a series of model superconductors with increasing coupling strength. It is demonstrated that the magnitude of the deviations can be estimated from the magnitude of the ratioT _c /〈ω〉, where〈ω〉 is an average phonon frequency. This rule does not apply to amorphous superconductors. The reason for this is shown to be due to the large weight ofα ² F(ω) at low frequencies which has been observed in these materials.     

Ion beam mixing of titanium films on stainless steel

The ion mixing of Ti-steel bilayers with N⁺, Ar⁺, Ti⁺, Kr⁺ and Xe⁺ ions was investigated by means of Rutherford backscattering spectroscopy (RBS). The mixing rates exhibit a linear scaling with the deposited damage energy f_D. No correlation between the properties of the mixing ion and the mixing efficiency was found. The results are compared with the predictions of ballistic and thermal-spike models.