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Using a Debye function analysis, the presence of icosahedral and face centered cuboctahedral gold in a 1 1 ratio has been found in freshly prepared Au/Mg(OH)2 catalyst. The results support earlier studies which suggest the icosahedral form to be more stable at small nanometer sizes. Interactions between the gold and the Mg(OH)2 support appear to be weak, with the gold rapidly coagulating over a period of three months. Re-analysis of the aged sample shows the gold to be mainly in the form of truncated decahedra. 相似文献
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Sebastian T. Vogel 《Ethik in der Medizin》2009,19(2):323-324
Fall und Kommentare
Gibt es eine Pflicht zum pr?natalen Nichtwissen? 相似文献7.
Integrating products and services to customized solutions can help firms to differentiate from their competitors. In practice, however, various companies fall short in extracting value from their customers. Therefore this paper focuses on pricing aspects as central means for value appropriation in the context of solutions. Following the resource-based view of the firm, we adopt a process-oriented perspective on pricing practices in order to identify crucial factors and activities. Based on 15 in-depth interviews with practitioners from various industries we derive six steps of a price management process for value appropriation in the context of solution selling and present critical activities and routines within each step. 相似文献
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Jörg Becker Daniel F. Beverungen Ralf Knackstedt 《Information Systems and E-Business Management》2010,8(1):33-66
Confronted with decreasing margins and a rising customer demand for integrated solutions, manufacturing companies integrate
complementary services into their portfolio. Offering value bundles (consisting of services and physical goods) takes place
in integrated product–service systems, spanning the coordinated design and delivery of services and physical goods for customers.
Conceptual Modeling is an established approach to support and guide such efforts. Using a framework for the design and delivery
of value bundles as an analytical lens, this study evaluates the current support of reference models and modeling languages
for setting up conceptual models for an integrated design and delivery of value bundles. Consecutively, designing modeling
languages and reference models to fit the requirements of conceptual models in product–service systems are presented as upcoming
challenges in Service Research. To guide further research, first steps are proposed by exemplarily integrating reference models
and modeling languages stemming from the service and manufacturing domains. 相似文献
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Minhong Wang Huaiqing Wang Doug Vogel Kuldeep Kumar Dickson K.W. Chiu 《Engineering Applications of Artificial Intelligence》2009,22(7):1046-1055
Modern businesses are facing the challenge of effectively coordinating their supply chains from upstream to downstream services. It is a complex problem to search, schedule, and coordinate a set of services from a large number of service resources under various constraints and uncertainties. Existing approaches to this problem have relied on complete information regarding service requirements and resources, without adequately addressing the dynamics and uncertainties of the environments. The real-world situations are complicated as a result of ambiguity in the requirements of the services, the uncertainty of solutions from service providers, and the interdependencies among the services to be composed. This paper investigates the complexity of supply chain formation and proposes an agent-mediated coordination approach. Each agent works as a broker for each service type, dedicated to selecting solutions for each service as well as interacting with other agents in refining the decision making to achieve compatibility among the solutions. The coordination among agents concerns decision making at strategic, tactical, and operational level. At the strategic level, agents communicate and negotiate for supply chain formation; at the tactical level, argumentation is used by agents to communicate and understand the preferences and constraints of each other; at the operational level, different strategies are used for selecting the preferences. Based on this approach, a prototype has been implemented with simulated experiments highlighting the effectiveness of the approach. 相似文献
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Ralf Steinmetz Author VitaeAndré KönigAuthor Vitae 《Performance Evaluation》2011,68(9):750-767
Recent developments in the area of decentralized and infrastructureless systems opened avenues for novel applications. Along with these new technologies, new questions regarding their operational bounds in terms of e.g. scalability and security arose. Due to the sparse presence of real-world decentralized and infrastructureless systems, new protocols and applications have to be scrutinized by means of simulation, in (small-scale) testbeds, and by analytical models. In this paper, we discuss challenges of evaluating security mechanisms for mobile ad hoc networks and peer-to-peer systems. We focus on harmonizing predictions of analytical models and results obtained from simulation studies and testbed experiments. 相似文献