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Application of Robust and Adaptive Pole Placement
The previous investigation showed the usefulness of a two-degree-of-freedom configuration. Such a controller can also be designed using pole placement. An adaptive controller based on this concept is developed and applied to the problem with good results. Particular features, like selection of model structure, design parameters and excitation, are also discussed.
Cykeln och bilsamhället
Time dependent study of multiple exciton generation in nanocrystal quantum dots
We study the exciton dynamics in an optically excited nanocrystal quantum dot. Multiple exciton formation is more efficient in nanocrystal quantum dots compared to bulk semiconductors due to enhanced Coulomb interactions and the absence of conservation of momentum. The formation of multiple excitons is dependent on different excitation parameters and the dissipation. We study this process within a
Strategies for Quantitative Planar Laser-Induced Fluorescence of NH Radicals in Flames
Laser-induced fluorescence imaging of the NH radical using excitation in the (0-0) and (1-0) vibrational bands of the A3Π-X3Σ– electronic transition is characterized in premixed NH3-air flames. Filtered detection for excitation of the (1-0) band is found to be beneficial for measurement conditions with a challenging background and/or interferences. Concentration evaluation for excitation in the (0
Time- and Space-Resolved SAXS Experiments Inform on Phase Transition Kinetics in Hydrated, Liquid-Crystalline Films of Polyion-Surfactant Ion "complex Salts"
Detailed time- and space-resolved SAXS experiments show the variation with hydration of liquid crystalline structures in ethanol-cast 5-80 μm thick films of polyion-surfactant ion "complex salts" (CS). The CS were dodecyl- (C12) or hexadecyl- (C16) trimethylammonium surfactants with polyacrylate (DP 25 or 6000) counter-polyions. The experiments were carried out on vertical films in humid air above
Identification of regions with less-developed research and innovation systems
Cracks in the Corporatisation of Feminism
Land access constraints for communities affected by large-scale land acquisition in Southern Sierra Leone
While national figures of land availability are used to justify accepting large-scale land investors, not very much is known about the local level realities of land availability. By combining remotely sensed data with fieldwork, system dynamics modelling and qualitative research methods, we examine local level realities of land use and availability in the Malen Chiefdom of Southern Sierra Leone. H
Laminar burning velocity of acetic acid + air flames
Laminar burning velocities of acetic acid + air flames at 1 atm and initial gas temperatures of 338 K, 348 K, and 358 K were determined using the heat flux method. Measurements were performed in non-stretched flames, stabilized on a perforated plate burner at adiabatic conditions. Due to experimental problems related to the corrosiveness of acetic acid towards the burner material, the uncertainty
Prosumers in district heating networks - A Swedish case study
A prosumer is a customer that both uses and supplies energy, such as electricity or district heat. These are already a part of the electricity system. Lately, prosumers have also been discussed as a part of the district heating systems. This calls for more knowledge in this area. The present study seeks to evaluate the potential for district heating contribution from small scale prosumers, based o
On optimal low-rank approximation of non-negative matrices
For low-rank Frobenius-norm approximations of matrices with non-negative entries, it is shown that the Lagrange dual is computable by semi-definite programming. Under certain assumptions the duality gap is zero. Even when the duality gap is non-zero, several new insights are provided.
Stochastic analysis of nucleation rates
We show that approximating the Becker-Döring equations with a Langevin equation results in multiplicative noise, which in turn leads to a family of possible Fokker-Planck equations according to the Ito-Stratonovich dilemma. Using a simple and general model for the attachment and detachment rates, we find that the Ito choice approximates the nucleation rate best and also coincides with the Fokker-P
Finding the gap : A brightness-based strategy for guidance in cluttered environments
The ability to move safely between obstacles is critical for animals that fly rapidly through cluttered environments but surprisingly little is known about how they achieve this. Do they reactively avoid obstacles or do they instead fly towards the gaps between them? If they aim towards gaps, what information do they use to detect and fly through them? Here, we aim to answer these questions by pre
Amplifier Design Using Vertical InAs Nanowire MOSFETs
In this paper, an amplifier design using ballistic vertical InAs nanowire (NW) transistors is investigated, focusing on a basic common-source amplifier. The maximum power gain at 90 GHz is evaluated for different NW transistor architectures together with the power dissipation. The linearity of the amplifier is evaluated by estimating the IIP3 and 1-dB compression points. Furthermore, the impact of
uL11, a central player in translation
Chlorine-Free Synthesis of Organic Alkyl Carbonates and Five- and Six-Membered Cyclic Carbonates
This report presents a new, one-pot, facile, selective and green method for methoxycarbonylation of alcohols and synthesis of five- and six-membered cyclic carbonates from corresponding alcohols with dimethyl carbonate (DMC) in the presence of molecular sieves without any additional solvent and catalyst. Syntheses of bifunctional structures comprising a six-membered cyclic carbonate with allyl eth
A Practical Robustness Theorem for Adaptive Control
Coordination of care in the Nordic countries
Coordination of health care exists at many different levels and in many different forms. We describe the similarities and differences in coordination mechanisms among the Nordic countries. In some respects, the Nordic countries approach coordination problems in similar ways although differences exist. The overall pattern shows that Finland and Sweden have less country-wide coordination compared wi
General practice in the Nordic countries
Background: General practice systems in the Nordic countries share certain common features. The sector is based on the Nordic model of a tax-financed supply of services with a political objective of equal access for all. The countries also share the challenges of increased political expectations to deliver primary prevention and increased workload as patients from hospital care are discharged earl