Performance analysis of adaptive scheduling in integrated services UMTS networks

For an integrated services UMTS network serving speech and data calls, we propose, evaluate and compare different scheduling schemes, which dynamically adapt the shared data transport channel rates to the varying speech traffic load. within each cell, the assigned data transfer resources are distributed over the present data flows according to certain fairness objectives. The performance of the adaptive schemes is numerically evaluated by means of analytical performance optimisation methods in combination with Monte Carlo simulations.\ud \u

A simple visual model to compare existing nutrient profiling schemes

Nutrient profiling is a highly pressing issue. However, as there are currently various nutrient profiling schemes it may be difficult to maintain an overview. We therefore developed a simple visual model where the various choices that can be made are indicated. This allows for easy comparison of existing schemes. The model is available in PowerPoint format and attached as a separate file to this paper (see Supplementary files under Reading Tools online)

Dynamic Duopoly with Intertemporal Capacity Constraints

We analyze strategic firm behavior in settings where the production stage is followed by several periods during which only sales take place. We analyze the dynamics of the market structure, the development of prices and sales over time, and the implications for profits and consumer surplus. Two specific settings are analyzed. In the first, a firm can commit up-front to a sales strategy that does not depend on the actual sales of its competitor. In this case there is a unique Nash equilibrium and price increases over time. In the second setting,there is no commitment and firms can adjust their sales in response to observed supply of their competitor in the previous period. It is shown that in this case a subgame perfect Nash equilibrium does not always exist. Equilibria can have surprising features. For some parameter constellations, price may decrease over time. It is also possible that the firm increases its pro�t by destroying some of its production. When firms have equal size, the equilibrium outcome is the same in both the commitment and the non-commitment setting. In general, the setting without commitment is bene�cial to the larger firm, whereas the setting with commitment leads to higher pro�ts for the smaller firm.mathematical economics;

Supporting deconstruction practices with information systems using ethnographic-action research

Socio-environmental pressures motivate the construction industry to adopt working practices that enable the reuse of building elements. Deconstruction, as an alternative to demolition, is a major lever for more efficient resource management and enables closed-loop material cycles. Information systems have potential benefits for deconstruction practices, but their implementations are limited by a lack of understanding on how demolition workers create, exchange and communicate information and what artefacts they thereby use. This research has therefore two goals: understanding on-site information requirements in deconstruction projects and exploring how information systems can be iteratively developed and implemented into these project contexts. Through applying an ethnographic-action research methodology on a real-world deconstruction project, two information systems are iteratively developed and implemented: (I) a virtual environment to support tagging façade elements, and (II) a 4D model to support deconstruction planning. Insights are provided – firstly – into deconstruction routines and the tacit knowledge that demolition workers possess and use to deal with these routines, and – secondly – into how the two information systems supported the practitioners in their ongoing project works. These ethnographic-action perspectives provide new ways for researchers and practitioners to support deconstruction practices with information systems