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991.
Biodegradation of pretreated olive mill effluent in mixture with a domestic sewage or compatible wastewater stream
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992.
This paper contributes to process studies on organizational creativity by developing two competing research agendas. The first perspective, the ‘becoming’ view, depicts creativity as a constant flow of activity that crystallizes every once in a while in unpredictable moments of creativity. The second perspective, the ‘practice’ view, understands creativity as a practised social process, in which structures play the important role of both enabling and constraining individual agents in pursuing creativity as a collective phenomenon. We compare and contrast these two theoretical perspectives, which are based on different process ontologies, and discuss their methodological implications. We argue that the practice perspective offers particular promise, because it allows us to address the important yet paradoxical question of how creativity may be organized and managed. 相似文献
993.
Piotr Piela Jens Mitzel Erich Gülzow Jürgen Hunger Alexander Kabza Ludwig Jörissen Francesco Valle Alberto Pilenga Thomas Malkow Georgios Tsotridis 《International Journal of Hydrogen Energy》2017,42(31):20187-20200
The direct-search simplex method for function optimization has been adapted to performance optimization of polymer electrolyte membrane fuel cells (PEMFCs). The established method is strongly application oriented and uses only experimentally determined data for optimization. It is not restricted to discrete parameters optimums and does not require the use of third-party software or computational resources. Hence, it is easy to implement in fuel cell testing stations. The optimization consists of finding, for a given fuel cell load, an optimum set of values of the 7 fuel cell operating parameters: the fuel cell temperature, the reactants' stoichiometric ratios, the reactants' inlet relative humidity, and the reactants' outlet pressures, resulting in the highest fuel cell performance. The performance is measured using a scalar function of the operating parameters and the load and can be defined according to needs.Two PEMFC performance functions: the fuel cell voltage and the system-related fuel cell efficiency were optimized using the procedure for practically sized PEMFC stacks of two designs. With respect to the nominal operating conditions defined as optimal for each stack design by its manufacturer, the gains from the optimization procedure were up to over 12% and up to over 7% for the stack voltage and efficiency, respectively. The validation of the procedure involved 5 stack specimens and four laboratories and consistent results were obtained. 相似文献
994.
A protective layers were prepared on a magnesium electrode by treatment in different solutions and times after modification
in 0.15 M HCl for 20 seconds. The corrosion of magnesium coated protective layer with different compounds was studied by using
potential-time, current-potential curves and AC impedance spectra. The coatings morphology depends on the treating bath compositions
and immersion times. The protective efficiencies of the surface layers were calculated by using corrosion rates obtained by
extrapolation of Tafel zones of current-potential curves to the corrosion potential and by using Stern-Geary equation with
polarization resistance from impedance spectra. 相似文献
995.
V. B. Martins T. P. Nagasima L. T. F. Eleno C. G. Schön 《Journal of Phase Equilibria and Diffusion》2017,38(3):195-200
The Pb–Bi (Lead–Bismuth) binary system has gained some prominence in recent years due to the possible use of eutectic alloys as primary-circuit coolant in generation IV nuclear reactors. Apart from the terminal solid solutions A1-Pb and A7-Bi, the system presents also one intermetallic phase with the hexagonal close-packed structure (A3), usually denoted ε phase. Due to the low temperatures involved in this system, attainment of equilibrium is difficult, and in addition, the proximity of x-ray scattering factors for both elements raises questions about a possible polymorphic transition. In the present work, three samples with compositions Pb–29 wt.%Bi, Pb–31 wt.%Bi and Pb–33 wt.%Bi were prepared and characterized by x-ray diffraction. The lattice parameters of ε are consistent with those reported in the literature, and their dependence on Bi content was determined as well. Only the hexagonal phase was identified in the 29 wt.%Bi sample, although the currently assessed Pb–Bi phase diagram predicts the presence of the Pb-rich A1 terminal solid solution in this composition. A 2-year annealing at room temperature was performed and the XRD characterization results for these samples are compared with the original data. 相似文献
996.
997.
Per Kreuger Rebecca Steinert Olof Görnerup Daniel Gillblad 《International Journal of Network Management》2018,28(2)
Managing and balancing load in distributed systems remains a challenging problem in resource management, especially in networked systems where scalability concerns favour distributed and dynamic approaches. Distributed methods can also integrate well with centralised control paradigms if they provide high‐level usage statistics and control interfaces for supporting and deploying centralised policy decisions. We present a general method to compute target values for an arbitrary metric on the local system state and show that autonomous rebalancing actions based on the target values can be used to reliably and robustly improve the balance for metrics based on probabilistic risk estimates. To balance the trade‐off between balancing efficiency and cost, we introduce 2 methods of deriving rebalancing actuations from the computed targets that depend on parameters that directly affects the trade‐off. This enables policy level control of the distributed mechanism based on collected metric statistics from network elements. Evaluation results based on cellular radio access network simulations indicate that load balancing based on probabilistic overload risk metrics provides more robust balancing solutions with fewer handovers compared to a baseline setting based on average load. 相似文献
998.
999.
Software failures in medical devices can lead to catastrophic situations. Therefore, it is crucial to handle software-related risks when developing medical devices, and there is a need for further analysis of how this type of risk management should be conducted. The objective of this paper is to collect and summarise experiences from conducting risk management with an organisation developing medical devices. Specific focus is put on the first steps of the risk management process, i.e. risk identification, risk analysis, and risk planning. The research is conducted as action research, with the aim of analysing and giving input to the organisation’s introduction of a software risk management process. First, the method was defined based on already available methods and then used. The defined method focuses on user risks, based on scenarios describing the expected use of the medical device in its target environment. During the use of the method, different stakeholders, including intended users, were involved. Results from the case study show that there are challenging problems in the risk management process with respect to definition of the system boundary and system context, the use of scenarios as input to the risk identification, estimation of detectability during risk analysis, and action proposals during risk planning. It can be concluded that the risk management method has potential to be used in the development organisation, although future research is needed with respect to, for example, context limitation and how to allow for flexible updates of the product. 相似文献
1000.
Univ.-Doz. Mag. Dr. Anton Köck Livia Chitu Stefan Defregger Elke Kraker Günther Maier Stephan Steinhauer Robert Wimmer-Teubenbacher 《BHM Berg- und Hüttenm?nnische Monatshefte》2014,159(9):385-389
We report on the synthesis of SnO2 and CuO nanowires and their application as gas sensing components. The fabrication of SnO2 and CuO single nanowire devices by optical and electron beam lithography is described, and sensing performance to the toxic gas carbon monoxide is demonstrated. We briefly present the development of CMOS fabricated micro-hotplates as platforms for gas sensors and show our approach for nanowire implementation. Finally, we demonstrate a fully CMOS integrated CuO multi nanowire device and present our roadmap for a fully integrated multi-parameter smart sensor device which could be implemented as safety feature in smart phones. 相似文献