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31.
Andreas Klenk Andreas Beck-Greinwald Hannes Angst Georg Carle 《Service Oriented Computing and Applications》2012,6(4):321-335
Inter-domain collaborations suffer not only from technological obstacles that hinder interoperability, but also from diverting business objectives of the involved domains. Today, hand-crafted contracts define the terms and conditions for service interactions. Electronic negotiation can serve as the enabler of dynamic interdomain collaborations by providing a large degree of freedom for the automation of agreement formation and electronic contracting. Negotiation by electronic means has been an area of intensive research for many years now. However, most effort was put on the determination of prices and neglected that real-world agreements also consist of complex dependencies of interdependent obligations. In this paper we present agreement negotiation as a tool to establish ad hoc services collaborations. Our novel protocol allows for the discovery of complex agreement options and for the formation of multi-party agreements. The protocol works through an iterative exchange of requirements and offers. A major benefit over existing bilateral negotiation protocols is that our protocol is capable of discovering potential collaborations between different parties. It will leave each negotiating party with a complete agreement document after a successful negotiation. This comprehensive agreement document defines the interdependent obligations between all parties and is well suited for E-Contracting. 相似文献
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The electrochemical behaviour of several natural ilmenites has been studied by cyclic voltammetry. From the analysis of the current-voltage curves it was concluded that the valences of the metal ions in FeTiO3 are FeII and TiIV. It was also found that little amounts of FeIII and excess of TiIV (probably TiO2) can enter into the composition of the ilmenites. 相似文献
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Crosslinked poly(4-styrenesulfonic acid chloride) was reacted with 3-amino-4-hydroxyphenyl benzoate to give a reactive carrier after saponification and oxidation. Its binding ability was tested with α-chymotrypsin. The binding ability as well as the enzyme activity could be increased by introduction of spacers, e.g. ethylenediamine and hexamethylenediamine between the poly(styrene)-matrix and p-benzoquinone. Also crosslinked poly(vinyl alcohol) was reacted with p-benzoquinone to give a reactive carrier, which could also immobilize α-chymotrypsin. Some properties of the immobilized α-chymotrypsin as activity, pH-optimum and storage stability were investigated. 相似文献
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L. Wieth K. Kelemen S. Braun R. Koch H.-J. Bauer H. P. Schuchmann 《Microfluidics and nanofluidics》2016,20(2):42
High-pressure homogenization is a widely used process in the food, pharmaceutical, and cosmetic industry for producing emulsions. Because of small dimensions and high velocities, the experimental and numerical investigation of such a process is challenging. Hence, the development of products is mostly based on trial and error. In this paper, simulations of a generic high-pressure homogenization process using the Lagrangian, mesh-free smoothed particle hydrodynamics (SPH) method are presented and compared to experimental findings using Micro-Particle Image Velocimetry (μ-PIV). The SPH code has been developed and validated with the scope of simulating technical relevant multi-phase problems (Höfler et al. 2012). The present simulations cover the investigation of two different dynamic viscosities of the dispersed phase as well as different droplet trajectories. The comparison between the simulations and the experiments focusses on the velocity distribution of the continuous phase and the droplet deformation and breakup. In both cases a qualitatively good agreement is observed, demonstrating the ability of our SPH implementation for simulating technical relevant two-phase flows. 相似文献