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Paleo-ice sheet reconstructions are complicated by large uncertainties, particularly since it is usually only possible to infer thickness from indirect means such as the response of glacial isostatic adjustment (GIA). GIA itself has large uncertainties with respect to the rheological structure of the Earth, and it is possible to get multiple possible best fitting ice sheet configurations using different Earth models. Usually the best geological constraints for paleo-ice sheets are ice margin location, via dating methods and geomorphological features. Using the program ICESHEET (Gowan et al 2016), it is possible to exploit this knowledge and create glaciologically consistent ice sheet reconstructions for use in GIA modeling. We demonstrate this by applying them to the North American Laurentide and Innuitian ice sheets, and show that it is possible to have an ice sheet that has a much lower profile than other GIA constrained reconstructions such as ICE-6G, GLAC-1 and ANU. A lower profile ice sheet has profound implications for past climate reconstructions, including radically different atmospheric and Atlantic Ocean circulation at the Last Glacial Maximum. Such a reconstruction is better able to fit geological constraints in the near field, but are at odds with global sea level reconstructions that require much larger ice volume. We discuss possible solutions to this issue. Another benefit of ICESHEET is that it does not require climatic information, since the ice thickness is adjusted by changing a spatially and temporarily variable basal shear stress parameter. Using these reconstructions in climate models do not face the circularity of dynamic ice sheet models that require a climatic input that was often derived from a-priori ice sheet reconstructions.

The main objective of this study was to elucidate the possibilities to use wheat gluten (WG) as a binder for particleboards, as well as soy protein isolate (SPI). The focus was on the effect of the adhesive formulation and the processing conditions, while the press parameters were kept constant. Some aspects of the dispersion and the preparation of the dispersions that were investigated are: the time (1, 3 or 5h) to prepare the dispersion, the temperature (room temperature, 50 or 80°C) during the preparation of the dispersions and the effect of storing (1, 2.5 or 4 days) the dispersions. Furthermore, the utilization of green particles versus dried particles was examined. The concentration (12, 16, 20 or 24%) of WG dispersion and the process for applying it to the particles was studied. Two application methods were evaluated, in application method 1 (appl. 1) all the dispersion was added to the particles in one step before the particles were dried. When application method 2 (appl. 2) was employed the dispersion was added in two steps, some of the dispersion was added before the drying and some after the drying. The considered board properties were internal bond (IB), thickness swelling (TS) and water absorption (ABS). The results show that in the case of SPI dispersion the temperature seems to not be of significant importance and it appears as if longer time to prepare the dispersion is beneficial. On the other hand for WG dispersion it looks as if a lower temperature is preferable for the preparation of the dispersion and that the time to prepare the dispersion is of no importance. Furthermore, storing the dispersions for more than one day before it was used as an adhesive for particleboards (PB) resulted in poorer boards. According to this study it is beneficial to use dried particles instead of green particles. Additionally, the results show that the interaction between the concentration of WG dispersion and how it is applied is a significant factor, considering the IB value. However, in general the two step process (appl. 2) is preferable. Huvudsyftet med den här studien var att undersöka möjligheterna att använda vetegluten (WG) som bindemedel för spånskivor, även sojaproteinisolat (SPI) har undersökts. Fokus låg på effekten av formuleringen av bindemedlet och processbetingelserna, medan pressparametrarna hålls konstanta. En del parametrar som studerades med avseende på tillverkning av dispersionerna var: tiden (1, 3 eller 5 h) att bereda dem, vid vilken temperatur (rumstemperatur, 50 eller 80°C) de preparerades och effekten av att lagra (1, 2,5 eller 4 dagar) dispersionerna. Vidare, undersöktes användning av råspån kontra torkat spån. Koncentrationen (12, 16, 20 eller 24 %) för WG-dispersionerna och processen för belimning med dessa dispersioner utvärderades. Två applikationsmetoder testades, i applikationsmetod 1 tillsattes hela mängden dispersion i ett steg till spånet innan det torkades. I applikationsmetod 2 tillsattes dispersionen i två steg en del tillsattes innan torkning och resten tillsattes efter torkning. Skivegenskaperna som utvärderades var, tvärdrag (IB), svällning (TS) och absorption (ABS). Resultaten visade att det kan vara fördelaktigt att tillreda SPI-dispersioner under en längre tid och det verkar inte som att temperaturen är en viktig parameter. Däremot förefaller det som att lägre temperatur är gynnsamt när en WG-dispersion ska blandas och att tiden inte är av signifikant betydelse. Vidare, förefaller det som att lagring längre än en dag av dispersionerna har en negativ effekt på deras förmåga som bindemedel för spånskivor. Enligt den här studien är det fördelaktigt med avseende på skivegenskaper att använda torkat spån istället för råspån. Resultaten visar att samverkan mellan koncentration och applikationsmetod kan vara en signifikant faktor, med avseende på IB-värdena. Dock verkar det överlag som att tvåstegsbelimningen är fördelaktig. QC 20110518

This thesis investigates the design and performance of a model predictive controller (MPC) for the automatic control of hypnosis. It constitutes the first step towards automatic control of anesthesia with constraints on important parameters such as drug concentrations in the body and hemodynamic variables such as blood pressure. The literature suggests, that closed-loop control of anesthesia can significantly reduce drug consumption and lessen recovery times, thus improving the safety and quality of anesthesia care while reducing costs. However, automation of anesthesia is challenging because of shortcomings associated with drug-response modeling, in particular limited data for children and disagreement between published models, inadequate predictive capacity of models owing to inclusion of monitor dynamics in the models, and significant inter/intra patient variability and uncertainty in models. The first part of this thesis introduces a new approach to dose-response modeling and presents models with different clinical end-points for propofol in children and adults. This thesis also presents a new monitor-decoupledmodel of propofol pharmacodynamics (PD) where the monitor model is clearly excluded from the identified PD. The second part of the thesis concentrates on design of a constrained MPC for hypnosis. While the anesthesia closed-loop concept has already been investigated in the past, there is still a need for a closed-loop control system that explicitly includes robustness in the design step, allows constraints on drug concentrations and physiological parameters, and can incorporate multivariable control of multi drug and multi sensor systems. In this thesis, robust MPC controllers are presented for closed-loop control of depth of hypnosis in adults and children. Robustness in the presence of inter-patient variability is taken into account in the controller design. A novel idea is introduced on how to define and implement physiological constraints in closed-loop control of hypnosis using MPC with a parallel PKPD model. Evaluation of the proposed MPC meets the design specifications and shows that the required robustness against patient uncertainty is achieved and the proposed safety constrained control strategy can potentially reduce the risk of under/over-dosing for most patients by providing controller enforced safety bounds without sacrificing the performance of the closed-loop control system.

The development of the internet to a more interactive and communicative instance as well as new developments in the software industry and new services that are available to companies and users warrants an investigation of this emerging field of business. In order to shed light on this topic a systematic search of the current literature has been conducted using some specific areas of the software industry as search words (Cloud computing, open source, on line advertising, mobile software and service oriented architecture) dating back from 2007 until present. The relevant literature was then summarized, categorized and discussed based on the Porter’s strategic management approach; “the five competitive forces that shape strategy”, where the forces are rivals, customers, suppliers, substitute products and potential entrants. Recognition of these forces and some other effective factors on them, such as the industry’s growth rate, government, technology and innovation, and complementary products/services, provides a comprehensive analysis of the market situation, which is essential in strategic management for medium and long-term profitability. This study infers that for companies to take advantage of the opportunities arising from the emerging changes in the software industry, it is required to recognize the powerful forces of the industry, develop innovation, and be aware of the possible implication on several level of business administration, including the need for adopting new organizational schemes and new strategies.

A pose estimation method is proposed for measuring the position and orientation of a biopsy needle. The technique is to be used as a touchless needle guide system for guidance of percutaneous procedures with 4D ultrasound. A pair of uncalibrated, light-weight USB cameras are used as inputs. A database is prepared offline, using both the needle line estimated from camera-captured images and the true needle line recorded from an independent tracking device. A nonparametric learning algorithm determines the best fit model from the database. This model can then be used in real-time to estimate the true position of the needle with inputs from only the camera images. Simulation results confirm the feasibility of the method and show how a small, accurately made database can provide satisfactory results. In a series of tests with cameras, we achieved an average error of 2.4mm in position and 2.61° in orientation. The system is also extended to real ultrasound imaging, as the two miniature cameras capture images of the needle in air and the ultrasound system captures a volume as the needle moves through the workspace. A new database is created with the estimated 3D position of the needle from the ultrasound volume and the 2D position and orientation of the needle calculated from the camera images. This study achieved an average error of 0.94 mm in position and 3.93° in orientation.

The modeling of the atmospheric boundary layer over sea ice is still challenging because of the complex interaction between clouds, radiation and turbulence over the often inhomogeneous sea ice cover. There is still much uncertainty concerning sea ice roughness, near‐surface thermal stability and related processes, and their accurate parameterization. Here, a regional Arctic climate model forced by ERA‐Interim data was used to test the sensitivity of climate simulations to a modified surface flux parameterization for wintertime conditions over the Arctic. The reference parameterization as well as the modified one is based on Monin–Obukhov similarity theory, but different roughness lengths were prescribed and the stability dependence of the transfer coefficients for momentum, heat and moisture differed from each other. The modified parameterization accounts for the most comprehensive observations that are presently available over sea ice in the inner Arctic. Independent of the parameterization used, the model was able to reproduce the two observed dominant winter states with respect to cloud cover and longwave radiation. A stepwise use of the different parameterization assumptions showed that modifications of both surface roughness and stability dependence had a considerable impact on quantities such as air pressure, wind and near‐surface turbulent fluxes. However, the reduction of surface roughness to values agreeing with those observed during the Surface Heat Budget of the Arctic Ocean campaign led to an improvement in the western Arctic, while the modified stability parameterization had only a minor impact. The latter could be traced back to the model's underestimation of the strength of stability over sea ice. Future work should concentrate on possible reasons for this underestimation and on the question of generality of the results for other climate models., The modeling of the atmospheric boundary layer over sea ice is challenging. This is, among others, due to the distinct sea ice surface roughness and pressure ridges as shown in the image, and the often stably stratified atmosphere. We quantified the impact of used parameterizations and show that both surface roughness and stability dependence have a considerable impact on near‐surface turbulent fluxes and atmospheric circulation in Arctic climate simulations., German Research Foundation (DFG), Helmholtz Association (HGF), POLEX http://dx.doi.org/10.13039/100003872, Russian Science Foundation (RSF) http://dx.doi.org/10.13039/501100006769