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21.
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
22.
H. Schulz 《Holz als Roh- und Werkstoff》1985,43(6):215-222
- Sandblasting of hardwood and softwood cross-sections reveals unexpected hardness profiles, which may provide an extension to the conventional division of wood into annual rings, earlywood and latewood or zones of growth.
- Hard wooden parts which occur in cross-sections and which presumably contribute towards its strength, can also be traced in longitudinal cuts in the form of ridges.
- It is assumed that tree species build up different mechanical systems which can be varied during wood formation as the need arises.
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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
25.
A detailed analysis of the lipids of spider silk is given for the first time. Extracts of the silk from the golden orb weaver,
Nephila clavipes, were studied by gas chromatography, mass spectrometry, and chemical derivatizations. The major group of the lipids consisted
of methyl-branched 1-methoxyalkanes (methyl ethers) with up to four methyl groups in the chain (chain length between C28 and C34), which are unique to spiders. The position of the methyl branches was determined by conversion into cyanides, which allowed
easy location of methyl branches. The second-largest group included alkanes with a wide structural variety; 2-methyl-branched,
even-numbered hydrocarbons predominated. A general numerical method for the estimation of retention indices of alkanes and
their derivatives is presented. Further components of the web included alkanols and alkanediols, fatty acids, and glyceryl
ethers. Some comments on the biosynthesis of these compounds are also given. 相似文献
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SiliconLabs 《单片机与嵌入式系统应用》2014,(6):3-4
正对于当今的系统设计人员来说,通过一种快速且容易的方法把嵌入式系统连接到计算机已经成为系统设计的必要条件。而能使嵌入式应用与计算机通信的最常见方法是采用通用串行总线(USB),几乎可以在每一台台式电脑、笔记本电脑和平板电脑上发现通用串行总线。随着USB的普及,嵌入式开发人员面临着学习挑战,即如何使用USB协议以及如何把它集成到系统中。问题 相似文献
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Neural Processing Letters - Albeit automated classifiers offer a standard tool in many application areas, there exists hardly a generic possibility to directly inspect their behavior, which goes... 相似文献