Adaptierung der sensorischen Texturprofilanalyse 1. Mitteilung: Skalierung mechanischer Textureigenschaften

Zusammenfassung Die in den USA entwickelte sensorische Texturprofilanalyse stellt die aussagestärkste Methode zur quantitativen und qualitativen Bewertung der Texturunterschiede von Lebensmitteln dar. Vor der Anwendung in Regionen mit anderen Konsumgewohnheiten bedarf sie jedoch einer entsprechenden Adaptierung. Mitteilung 1 berichtet über modifizierte standardisierte Intensitätsskalen zur quantitativen Einstufung der mechanischen Textureigenschaften Festigkeit, Brüchigkeit, Kaubarkeit, weichelastisches Verhalten, Viskosität und Adhäsivität. Die Anpassung an das österreichische Lebensmittelspektrum erfolgte mittels rheologischer Vorprüfungen potentieller Standardpunkte und anschließender Fixierung der Normskalen durch ein geschultes Prüferpanel unter guter Korrelation zwischen instrumentellen und sensorischen Prüfungen.

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Adaption of sensory texture profile analysis 1. Scaling of mechanical properties

Summary Texture profile analysis, originally developed in the United States, represents the most complete system of both quantitative and qualitative sensory texture measurements of foodstuffs. Due to regionally varying habits of consumption, an adequate adaptation is necessary prior to application. This paper deals with the evaluation of the mechanical properties firmness, brittleness, chewiness, gumminess, viscosity and adhesiveness. Modifications of standard rating scales for typical Austrian food materials are reported. Rheological examination of commodities was followed by final establishment of standard scales with a trained panel. Good correlation between instrumental and sensory results was obtained.

     

The flavour of cape gooseberry (Physalis peruviana L.)

European Food Research and Technology - The volatile constituents of cape gooseberry (Physalis peruviana L.) were characterized using liquid/liquid extraction and fractionation of the flavour...     

Multi-Agent Radio Resource Allocation

This paper presents a spatially distributed and dynamic billing, pricing and allocation mechanism for which a user terminal requires Cognitive Radio abilities. That is, the Cognitive Radio abilities will be applied to the economical environment. The radio resource goods are allocated to the users by a multi-unit sealed-bid auction. Intelligent entities like the bidding strategy have to represent operator’s and users’ behavior and to make decisions for them in order to fulfill the preferences and QoS. The main functionalities, used to execute the dynamic auction sequence and located in the MAC are described, assuming the entities possess Cognitive Radio abilities.

Low-threshold room-temperature operation of injectorless quantum-cascade lasers: influence of doping density

The influence of the doping density in the active sections of InP-based injectorless quantum cascade lasers, emitting at 6.8 mum, is investigated. The doping sheet density is varied in the range 2.5-8.6times10¹⁰ cm^-2. Lasing is observed in the whole range, with a threshold current density as low as 1.2 kA/cm² at 300 K for the smallest doping sheet density of 2.5times10 ¹⁰ cm^-2. Further improvement has been made by additionally increasing the number of periods in the active region from 40 to 60. With the same doping level of 2.5times10¹⁰ cm^-2 record low threshold current densities of 0.73 kA/cm² at 300 K were achieved     

Kompetenzzentrum Wasserkraft

AktuellKelag und Rwe

Kompetenzzentrum Wasserkraft     

Modelling and prediction of phyto- and zooplankton dynamics in Lake Kasumigaura by artificial neural networks

An artificial neural network model was developed for Lake Kasumigaura to predict timing and magnitudes for chlorophyll a, five species of blue-green algae and three zooplankton groups. The model was trained by 8 years of limnological time series and validated by two independent years. The validation showed the potential of neural networks as predictive tools for highly non-linear phenomena such as blue-green algal blooms in freshwater lakes.     

Gyroid‐Structured 3D ZnO Networks Made by Atomic Layer Deposition

3D continuous ZnO morphologies with characteristic feature sizes on the 10 nm length scale are attractive for electronic device manufacture. However, their synthesis remains a challenge because of the low crystallization temperature of ZnO. Here, we report a method for the robust and reliable synthesis of fully crystalline 3D mesoporous ZnO networks by means of atomic layer deposition (ALD) of ZnO into a self‐assembled block copolymer template. By carefully optimizing the processing conditions we are able to synthesize several‐micrometer‐thick layers of mesoporous ZnO networks with a strut width of 30 nm. Two 3D mesoporous morphologies are manufactured: a periodic gyroid structure and a random worm‐like morphology. Exploiting the ALD property to conformally coat complex surfaces of high aspect ratio, the channel network of a 3D continuous channel network of a self‐assembled block copolymer is replicated into ZnO. X‐ray photoemission spectroscopy and x‐ray diffraction measurements reveal that the chemical composition of the mesoporous structures is uniform and consists of wurtzite‐ZnO throughout the film. Scanning electron microscopy reveals an average pore dimension of 30 nm. The potential of this material for a hybrid photovoltaic application is demonstrated by the manufacture of a poly(3‐hexylthiophene)/ZnO solar cell.     

A comparison of theoretical efficiencies of multi‐junction concentrator solar cells

Champion concentrator cell efficiencies have surpassed 40% and now many are asking whether the efficiencies will surpass 50%. Theoretical efficiencies of >60% are described for many approaches, but there is often confusion about “the” theoretical efficiency for a specific structure. The detailed balance approach to calculating theoretical efficiency gives an upper bound that can be independent of material parameters and device design. Other models predict efficiencies that are closer to those that have been achieved. Changing reference spectra and the choice of concentration further complicate comparison of theoretical efficiencies. This paper provides a side‐by‐side comparison of theoretical efficiencies of multi‐junction solar cells calculated with the detailed balance approach and a common one‐dimensional‐transport model for different spectral and irradiance conditions. Also, historical experimental champion efficiencies are compared with the theoretical efficiencies. Copyright © 2008 John Wiley & Sons, Ltd.     

On the impact of a more realistic physical layer on MANET simulations results

Network simulation tools are frequently used to analyze the performance of MANET protocols and applications. Currently they offer only simple wireless communication models that neglect many radio propagation effects. In this paper, we integrate a more realistic physical layer model into a simulation tool. It consists of a radio propagation model and a model of wireless transmission errors. They have been evaluated against real-world measurements. We prove that such more realistic models change simulation results considerably. To the best of our knowledge, no other study of MANETs has been performed so far with such a detailed physical layer model. Hence, this paper also gives new insights on the performance of MANETs in real outdoor environments.