I certain categories, an important element of competition is the use of previews to signal information to potential consumers about product attributes. For example, the front page of a newspaper provides a preview to potential newspaper buyers before they purchase the product. In this context, a news provider can provide previews that are highly informative about the content of the news product...

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This study presents a global scale analysis of cropping intensity, crop duration and fallow land extent computed by using the global dataset on monthly irrigated and rainfed crop areas MIRCA2000. MIRCA2000 was mainly derived from census data and crop calendars from literature. Global cropland extent was 16 million km around the year 2000 of which 4.4 million km (28%) was fallow, resulting in an...

Different methods for network-based mobile positioning were compared experimentally. The Cell-id and TA method provided limited accuracy, the uncertainty ranging from 500 m to 3000 m for the median, dependant on area type. This could be reduced up to 25% by using alternative radii based on observations in the “doughnut” shaped prediction area. The Planning tool method improved the accuracy by a...

Thesis Supervisor: Frédo Durand Title: Professor

Stress on the environment from a potentially growing energy use is set to rise. Without doubt the energy resources in Arctic regions will be developed. An important goal will be to exploit the resources offered by for instance the Barents Sea as a new European energy province, and to do this in accordance with the principles of sustainable development that have successfully been used e.g. in th...

Automation of agricultural harvesting equipment in the near term appears both economically viable and technically feasible. This paper describes the Demeter system for automated harvesting. Demeter is a computer-controlled speedrowing machine, equipped with a pair of video cameras and a global positioning sensor for navigation. Demeter is capable of planning harvesting operations for an entire ...