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81.
Univ.-Prof. DI Dr. Helmut Habersack DI Marlene Haimann Ass. Prof. Dr. Sándor Baranya Prof. Dr. János Józsa Mag. Angelika Riegler Dr Christine Sindelar DI Marcel Liedermann Johanna Ficsor Gabriella Mohácsiné Simon HR DI Dr. Michael Hengl 《?sterreichische Wasser- und Abfallwirtschaft》2014,66(9-10):340-347
The multiple uses of the Danube River for navigation, hydropower production and as a drinking water supply influence its ecological quality. Flow restrictions due to regulation as well as impacts on the sediment regime such as retention in the catchment area and interruption of the sediment continuum result in changes of the hydromorphological structures and can produce major problems in the context of sediment management. In light of these facts, cross-border investigations of sediment transport at the Danube River are called for. As there are no uniform research approaches shared by Austria and Hungary, the EU-funded project SEDDON (Sediment Research and Management at the Danube River) aims to compare different monitoring and modeling techniques used to determine sediment transport, and to develop mutual solutions. Further, the laboratory equipment currently used for hydraulic model experiments is evaluated and a research channel with a free flowing discharge of up to 10 m3/s without pumping will be constructed, allowing large-scale joint laboratory tests concerning sediment to be performed. 相似文献
82.
Chua Elizabeth F.; Schacter Daniel L.; Sperling Reisa A. 《Canadian Metallurgical Quarterly》2009,24(1):139
Although several studies have examined the neural basis for age-related changes in objective memory performance, less is known about how the process of memory monitoring changes with aging. The authors used functional magnetic resonance imaging to examine retrospective confidence in memory performance in aging. During low confidence, both younger and older adults showed behavioral evidence that they were guessing during recognition and that they were aware they were guessing when making confidence judgments. Similarly, both younger and older adults showed increased neural activity during low- compared to high-confidence responses in the lateral prefrontal cortex, anterior cingulate cortex, and left intraparietal sulcus. In contrast, older adults showed more high-confidence errors than younger adults. Younger adults showed greater activity for high compared to low confidence in medial temporal lobe structures, but older adults did not show this pattern. Taken together, these findings may suggest that impairments in the confidence–accuracy relationship for memory in older adults, which are often driven by high-confidence errors, may be primarily related to altered neural signals associated with greater activity for high-confidence responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
Marcel Kornelis Erica van Herpen Ivo van der Lans Lusiné Aramyan 《Food quality and preference》2010,21(5):512-520
Food companies, governments, and societal organizations use an increasing number of food-choice motives to persuade consumers to buy food products, and the question which combinations of motives matter for which type of consumer has become of central relevance. In this study, we use a concomitant mixture-modeling approach to uncover consumer segments in terms of food-choice motives, using a nationwide sample in the Netherlands. The results reveal seven segments with distinct profiles and demonstrate that age and membership of environmental organizations play an essential role in segment membership probabilities. Our findings support the idea that information about non-food-related consumer behavior improves the identification of segments. In an additional analysis, we demonstrate how organizational membership also provides an effective way to access consumer segments as compared to diverse media outlets. We discuss the implications of our findings for segmentation practice. 相似文献
84.
Marcel Müri Bernd Gotsmann Yann Leroux Marius Trouwborst Emanuel Lörtscher Heike Riel Marcel Mayor 《Advanced functional materials》2011,21(19):3706-3714
Due to the increasing importance of modified electrodes for many applications in nanotechnology, including molecular electronics, bioelectronics, and sensors, there is a need to find ways to chemically attach suitable molecular films onto the electrodes. Combining the electroreduction of aryl diazonium salts with the Sonogashira cross‐coupling reaction, a new modular technique to modify electrodes is presented. The new technique allows a wide range of functional groups to be introduced onto electrode surfaces with high surface coverage by the functional subunit. Various organic subunits, including redox chromophores, are successfully attached to platinum electrodes. The corresponding films are characterized using cyclic voltammetry, X‐ray photoelectron spectroscopy, atomic force microscopy, and contact‐angle measurements. The electroreduction of diazonium salts is successfully achieved on a broad variety of conducting and semiconducting surfaces, which shows that the technique is applicable to a broad variety of substrates. 相似文献
85.
Luigi Catuogno Hans Löhr Mark Manulis Ahmad-Reza Sadeghi Christian Stüble Marcel Winandy 《Datenschutz und Datensicherheit - DuD》2010,34(5):289-294
Trusted Virtual Domains (TVDs) provide a secure IT infrastructure offering a homogeneous and transparent enforcement of access
control policies on data and network resources. In this article, we give an overview of the fundamental ideas and basic concepts
behind TVDs, present a realization of TVDs, and discuss application scenarios. 相似文献
86.
Envy is the painful emotion caused by the good fortune of others. This research empirically supports the distinction between two qualitatively different types of envy, namely benign and malicious envy. It reveals that the experience of benign envy leads to a moving-up motivation aimed at improving one’s own position, whereas the experience of malicious envy leads to a pulling-down motivation aimed at damaging the position of the superior other. Study 1 used guided recall of the two envy types in a culture (the Netherlands) that has separate words for benign and malicious envy. Analyses of the experiential content of these emotions found the predicted differences. Study 2 and 3 used one sample from the United States and one from Spain, respectively, where a single word exists for both envy types. A latent class analysis based on the experiential content of envy confirmed the existence of separate experiences of benign and malicious envy in both these cultures as well. The authors discuss the implications of distinguishing the two envy types for theories of cooperation, group performance, and Schadenfreude. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Water sorption and dynamical properties of bread crust were studied using gravimetric sorption experiments. Water uptake and loss were measured while relative humidity (RH) was step-wise in- or decreased. Experimental results were compared with Fickian diffusion models and empirical models like the exponential and power-law model. From comparison of experimental sorption curves and the power-law model for short times it followed for all bread crust that the diffusional coefficient n is close to one. It turned out that this is not due to so-called case II diffusion and water transport that is limited by relaxation of the solid material but due to the fact that RH did not instantaneously but gradually increased to the set value.Sorption curves of isotherm experiments could be best described by the Fickian diffusion model for low RH and by the exponential model for large RH. Transport rates depend on moisture content and show a maximum around RH = 0.7, corresponding to a water mass fraction ω1 = 0.12. Diffusion rates could be well described by free volume theory up to the maximum, but this theory could not explain the strong decrease at higher ω1. Indications for a local glass-rubber transition at room temperature were found near a water mass fraction ω1 ≈ 0.09. This corresponds very well to the start of the crisp–non-crisp transition as measured by a sensory panel, but not to the glass-rubber transition at ω1 ≈ 0.12 as measured by other techniques like Differential Scanning Calorimetry. So it seems that more than one glass-rubber like transitions may be important to describe the properties of heterogeneous cellular food systems. 相似文献
88.
Marcel Marchand Wouter T. De Groot 《The International journal of environmental studies》2013,70(1-2):31-43
Third World rural planning involves the transfer of First World technologies to the socially and ecologically vulnerable tropical environment. This transfer is guided by normative, “ideological” views concerning social and environmental issues which often remain implicit. To uncover these views, a content analysis of a series of papers has been carried out, focused on impoldering as a type of project with far reaching social and environmental impacts. Three types of “ideologies” could be distinguished, which have been labelled as sociocratic, eco‐sociocratic and technocratic. They differentiate significantly with regard to (1) values attached to ecological and cultural systems, (2) preferred pace and scale of projects, (3) envisaged project feasibility, (4) the range of feasible alternatives, as well as (5) the institutional background of their adherents. The latter separation, however, is not complete. This may stimulate the growth of insight in the normative background of the seemingly objective rationality of project design. 相似文献
89.
Marcel Waintraub Roberto Schirru Cláudio M.N.A. Pereira 《Progress in Nuclear Energy》2009,51(6-7):680-688
Particle Swarm Optimization (PSO) is a population-based metaheuristic (PBM), in which solution candidates evolve through simulation of a simplified social adaptation model. Putting together robustness, efficiency and simplicity, PSO has gained great popularity. Many successful applications of PSO are reported, in which PSO demonstrated to have advantages over other well-established PBM. However, computational costs are still a great constraint for PSO, as well as for all other PBMs, especially in optimization problems with time consuming objective functions. To overcome such difficulty, parallel computation has been used. The default advantage of parallel PSO (PPSO) is the reduction of computational time. Master-slave approaches, exploring this characteristic are the most investigated. However, much more should be expected. It is known that PSO may be improved by more elaborated neighborhood topologies. Hence, in this work, we develop several different PPSO algorithms exploring the advantages of enhanced neighborhood topologies implemented by communication strategies in multiprocessor architectures. The proposed PPSOs have been applied to two complex and time consuming nuclear engineering problems: i) reactor core design (CD) and ii) fuel reload (FR) optimization. After exhaustive experiments, it has been concluded that: i) PPSO still improves solutions after many thousands of iterations, making prohibitive the efficient use of serial (non-parallel) PSO in such kind of real-world problems and ii) PPSO with more elaborated communication strategies demonstrated to be more efficient and robust than the master-slave model. Advantages and peculiarities of each model are carefully discussed in this work. 相似文献
90.
In the design process of transmissions, one major criterion is the resulting noise emission of the powertrain due to the gear excitation. Within the past years, a lot of investigations have shown that the noise emission can be correlated to the quasi-static transmission error. Therefore, the transmission error can be used as a characteristic value for quality assurance by experimental inspections as well as for a tooth contact analysis in the design process.The noise behavior of gearboxes is mainly caused by the excitation in the tooth mesh. The standardized design and calculation methods for gears concentrate on the reduction of the excitation level. But often the physical sound characteristics do not fit in with the human noise perception. Thus gear design rules are required that are able to rate the excitation according to the perception.The effect of the targeted topography scatter generally described is the reduction of the gear mesh amplitudes with an increase of the background noise. The objective of the report is to develop an understanding of the influence of different micro geometry scatters on the excitation behavior.Finally, it is the aim to design an aurally-accurate micro geometry scattering for the optimization of ground bevel gears in terms of tonality reduction and increased background noise. By means of a variant calculation and weighted target variables, psychoacoustic optimized micro geometry scattering is designed. At the same time, attention is also focused on a simple production of mixed topographies. 相似文献