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A strategy for control of substrate feed rate in fed-batch fermentations is presented. The main idea is to make pulses in the feed rate and to evaluate the response in the dissolved oxygen signal. This gives an indirect measurement of the substrate demand that is used for feedback control of the feed rate. Experimental data is used to develop a model of a fermentation process. The model is used to

Nanowires have the ability to absorb light much more efficient than conventional thin film layers. This makes them candidates for the development of new types of solar cells that have higher efficiency and lower material usage than current technologies. In this thesis fabrication of nanowires with techniques suitable for large area applications are investigated. The nanowires are grown by either M

In this paper, we introduce a new technique that allows the coexistence of secondary users (SUs) with a primary user (PU), in the same frequency and time. The proposed technique (i.e., the cluster-based spatial opportunistic spectrum sharing (CB-SOSS) technique) exploits the spatial degrees of freedom resulting from the use of multiple antennas at both the secondary base station (SBS) and SUs; als

The paper investigates advantages of using an MCCA-aware acknowledging system in IEEE 802.11s Wireless Mesh Networks (WMN). The MCCA (MCF controlled channel access) protocol allows for reserving time slots for a point-topoint transmission over a wireless link. The protocol assures that the transmission will not be hindered by any other 802.11 device that uses MCCA, by preventing all neighbors of b

In recent years, Worldwide Interoperability for Microwave Access (WiMAX) has become an important technology providing wireless connections for mobile terminals in a wireless Metropolitan Area Network (MAN), due to its large radio range. In a MAN environment, wireless clients always have high mobility; therefore, it is possible that the mobile clients will move away from the service coverage of ser

In order to reduce parasite-induced mortality, hosts may be involved in mutualistic interactions in which the partner contributes to resistance against the parasite. The pea aphid, Acyrthosiphon pisum Harris (Hemiptera: Aphididae), harbours secondary bacterial endosymbionts, some of which have been reported to confer resistance against aphid parasitoids. Although this resistance often results in d

In this paper, the thermal impact of using different steel laminations in the stator and the rotor of a permanentmagnet assisted synchronous reluctance machine designed for an automotive application is studied. In this regard, two main parameters of the steel lamination materials, thickness and amount of alloy content in weight percent, are studied. Frequency characteristics of the iron losses of