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  • 12851.
    Åleskog, Anna
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Norberg, Maria
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för genetik och patologi.
    Nygren, Peter
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för onkologi, radiologi och klinisk immunologi, Enheten för onkologi.
    Rickardson, Linda
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Kanduri, Meena
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för genetik och patologi.
    Tobin, Gerard
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för genetik och patologi.
    Åberg, Magnus
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Gustafsson, Mats G.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Rosenquist, Richard
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för genetik och patologi.
    Lindhagen, Elin
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper.
    Rapamycin shows anticancer activity in primary chronic lymphocytic leukemia cells in vitro, as single agent and in drug combination2008Inngår i: Leukemia and Lymphoma, ISSN 1042-8194, E-ISSN 1029-2403, Vol. 49, nr 12, s. 2333-2343Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The mammalian target of rapamycin inhibitor rapamycin and its analogues show promising anticancer activity in various experimental tumor models and are presently evaluated in clinical trials. We, here, evaluated the in vitro activity of rapamycin with regard to tumor-type specificity and possible mechanisms of drug resistance in 97 tumor cell samples from patients and in a resistance-based cell line panel, using the fluorometric microculture cytotoxicity assay. Rapamycin was dose-dependently cytotoxic in patient tumor cells and in cell lines. In primary cells, rapamycin was more active in hematological than in solid tumor samples, with chronic lymphocytic leukemia (CLL) and acute lymphocytic leukemia being the most sensitive tumor types. Considerable inter-individual differences in sensitivity were apparent among CLL samples, but no difference was observed between IGHV mutated and unmutated CLL samples, whereas a tendency to lower rapamycin sensitivity was indicated for samples displaying poor-prognostic genomic markers. Combination experiments in CLL cells indicated that rapamycin acted synergistically with vincristine, cisplatin, chlorambucil and taxotere. These results and the clinically-experienced good tolerance to rapamycin analogues encourage clinical studies of rapamycin in CLL treatment as single agent but also in combination with, e.g., vincristine and chlorambucil.

  • 12852.
    Ålin, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Metod för hantering av kalibrerparametrar för styrsystem2010Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Utvecklingen av motorstyrsystem på Scania CV AB är en komplicerad process där hård- och mjukvara kombineras i en färdig enhet för användning i de lastbilar som företaget producerar. Styrsystemet består bland annat av en datasats med en mängd parametrar som styr olika typer av funktionalitet. Parametrarna måste vid utvecklingen av en ny motor först kalibreras med korrekta värden och därefter måste dessa värden granskas för att kvaliteten på produkten ska kunna säkerställas. I dagsläget saknas ett standardiserat arbetssätt för hur kalibrering och granskning ska gå till på de grupper som är inblandade.

    Studien syftade till att kartlägga hur arbetet med kalibrering och granskning går till samt att om möjligt utveckla denna arbetsprocess för att uppnå en högre grad av kvalitetssäkring. Vad gäller processkartläggningen förekommer både skillnader och likheter mellan de, i processen, inblandade grupperna. Ett antal positiva rutiner och arbetsmetoder kunde urskiljas och dessa föreslås i den mån det är möjligt spridas i hela processflödet. Bland dessa finns exempelvis användandet av en sektionsövergripande roll med ansvar för granskningsarbetet, återkommande gruppgranskningar och noggrann dokumentation.

    Ett antal, i kalibrerings- och granskningsprocessen, inneboende problem har också identifierats. Med utgångspunkt i teori kring lean produktutveckling har förslag på förändringar i verksamheten som kan hantera dessa problem tagits fram. Sammanfattningsvis kan det konstateras att kalibrerings- och granskningsprocessen i många avseenden redan bedrivs utifrån LPS principerna. Det finns emellertid en del ändringar som ytterligare skulle kunna förbättra processerna och göra dessa mer lean, vilket också skulle bidra till kvalitetssäkring av slutprodukten.

  • 12853.
    Åman, Robert
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Understanding when customers leave: Defining customer health and how it correlates with software usage2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    More and more businesses today focus on building long-term customer relationships with the objective to secure recurring revenues in competitive markets. As a result, management philosophies such as Customer Success have emerged, which underlines the importance of knowing your customers in order to make them stay. A common way of tracking the well-being of a firm's customers is the use of customer health scores. Such tools monitor assembled data and indicate whether a customer is doing fine, or is in the risk zone of ending the business relationship. However, there exists little to no consensus on what customer health actually means, or how to distinguish suitable parameters for measuring this concept. Therefore, the purpose of this thesis has been:

    To extend the existing knowledge of the business concept customer health, and show how to identify relevant parameters for measuring customer health.

    To reach this purpose, a study has been conducted at a software-as-a-service company operating in the field of digital marketing; where methods such as semi-structured interviews, ethnography, web survey, data mining execution and statistical analysis have been used. The results show that software usage differs between active and former customers, with the general tendency that a high software usage indicates a higher propensity to stay as a customer. The study concludes that customer health is best defined as "the perceived value a customer experiences when using a product". In addition, the parameters that were found to best indicate customer health at the company studied were linked to customers’ software usage as well as their marketing set-up.

  • 12854.
    Ån, Henrik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Mickelsson, Lovisa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Sanderyd, Viktor
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Sedvall, Emelie
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Posluk, Patrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Sener, Kerime
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Processutrustning och laboratorieplanering2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
  • 12855.
    Ångman, Katarina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Kartläggning och utvärdering av produkter och tjänster kopplat till begreppet Smart Grids2012Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The Smart Grids development is driven by forces concerning safe electric

    transmission done in an energy efficient way. Vattenfall Eldistribution AB has a vision

    to transform their electricity network into Smart Grids. To invest in Smart Grids they

    have a need to show their customers what advantages they will get from the

    development. This led to the formulation of this dissertation project where the aim is

    to identify products and services related to Smart Grids that will increase the

    customer satisfaction for Vattenfall Eldistributions private customers.

    The project started with a mapping of existing products and services on the Swedish

    electricity market. From the mapping several development possibilities for Vattenfall

    Eldistribution were identified. Two of these development possibilities where analyzed

    more deeply as they seemed to have a grate possibility to fulfil the aim of the project.

    The two services that where studied more closely were follow-up on new electricity

    connections and an electricity usage report. The two services where analyzed from a

    market, organisation and strategy perspective.

    The findings from this study show that Vattenfall Eldistribution should introduce an

    electricity usage report for their private customers and that a pilot project should be

    carried out for follow-up on new electricity connections.

  • 12856. Ångström, Jonas
    et al.
    Johansson, Robert
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialteori.
    Sarkar, Tapati
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Sorby, Magnus H.
    Inst Energy Technol, Phys Dept, NO-2027 Kjeller, Norway..
    Zlotea, Claudia
    CNRS UPEC, Inst Chim & Mat Paris Est, F-94320 Thiais, France..
    Andersson, Mikael S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Nordblad, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Scheicher, Ralph H.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialteori.
    Haussermann, Ulrich
    Stockholm Univ, Dept Mat & Environm Chem, SE-10691 Stockholm, Sweden..
    Sahlberg, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Oorganisk kemi.
    Hydrogenation-Induced Structure and Property Changes in the Rare-Earth Metal Gallide NdGa: Evolution of a [GaH](2-) Polyanion Containing Peierls-like Ga-H Chains2016Inngår i: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 55, nr 1, s. 345-352Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The hydride NdGaH1+x (x approximate to 0.66) and its deuterized analogue were obtained by sintering the Zintl phase NdGa with the CrB structure in a hydrogen atmosphere at pressures of 10-20 bar and temperatures near 300 degrees C. The system NdGa/NdGaH1+x exhibits reversible H storage capability. H uptake and release were investigated by kinetic absorption measurements and thermal desorption mass spectroscopy, which showed a maximum H concentration corresponding to "NdGaH2" (0.93 wt % H) and a two-step desorption process, respectively. The crystal structure of NdGaH1+x was characterized by neutron diffraction (P2(1)/m, a = 4.1103(7), b = 4.1662(7), c = 6.464(1) angstrom, beta = 108.61(1)degrees Z = 2). H incorporates in NdGa by occupying two distinct positions, H1 and H2. HI is coordinated in a tetrahedral fashion by Nd atoms. The H2 position displays flexible occupancy, and H2 atoms attain a trigonal bipyramidal coordination by centering a triangle of Nd atoms and bridging two Ga atoms. The phase stability and electronic structure of NdGaH1+x, were analyzed by first-principles DFT calculations. NdGaH1H2 (NdGaH2) may be expressed as Nd3+(H1(-)[GaH2](2-). The two-dimensional polyanion [GaH](2-) features linear -H-Ga-H-Ga- chains with alternating short (1.8 A) and long (2.4 angstrom) Ga-H distances, which resembles a Peierls distortion. H2 deficiency (x < 1) results in the fragmentation of chains. For x = 0.66 arrangements with five-atom moieties, Ga-H-Ga-H-Ga are energetically most favorable. From magnetic measurements, the Curie-Weiss constant and effective magnetic moment of NdGaH1.66 were obtained. The former indicates antiferromagnetic interactions, and the latter attains a value of similar to 3.6 mu(B), which is typical for compounds containing Nd3 ions.

  • 12857.
    Årdal, Christine
    et al.
    Norwegian Inst Publ Hlth, Div Infect Control & Environm Hlth, N-0403 Oslo, Norway..
    Baraldi, Enrico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Ciabuschi, Francesco
    Uppsala Univ, Dept Business Studies, Uppsala, Sweden..
    Outterson, Kevin
    Boston Univ, Sch Law, Boston, MA 02215 USA.;CARB X, Boston, MA USA..
    Rex, John H.
    CARB X, Boston, MA USA..
    Piddock, Laura J. V.
    Univ Birmingham, Inst Microbiol & Infect, Birmingham, W Midlands, England..
    Findlay, David
    GlaxoSmithKline, London, England..
    To the G20: incentivising antibacterial research and development2017Inngår i: Lancet. Infectious diseases (Print), ISSN 1473-3099, E-ISSN 1474-4457, Vol. 17, nr 8, s. 799-801Artikkel i tidsskrift (Annet vitenskapelig)
  • 12858. Årdal, Christine
    et al.
    Baraldi, Enrico
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Theuretzbacher, Ursula
    Outterson, Kevin
    Plahte, Jens
    Ciabuschi, Francesco
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Företagsekonomiska institutionen.
    Røttingen, John-Arne
    Insights into early stage of antibiotic development in small- and medium-sized enterprises:: a survey of targets, costs, and durations2018Inngår i: Journal of Pharmaceutical Policy and Practice, Vol. 11, nr 8Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background

    Antibiotic innovation has dwindled to dangerously low levels in the past 30 years. Since resistance continues to evolve, this innovation deficit can have perilous consequences on patients. A number of new incentives have been suggested to stimulate greater antibacterial drug innovation. To design effective solutions, a greater understanding is needed of actual antibiotic discovery and development costs and timelines. Small and medium-sized enterprises (SMEs) undertake most discovery and early phase development for antibiotics and other drugs. This paper attempts to gather a better understanding of SMEs’ targets, costs, and durations related to discovery and early phase development of antibacterial therapies.

    Methods

    DRIVE-AB, a project focused on developing new economic incentives to stimulate antibacterial innovation, held a European stakeholder meeting in February 2015. All SMEs invited to this meeting (n = 44) were subsequently sent a survey to gather more data regarding their areas of activity, completed and expected development costs and timelines, and business models.

    Results

    Twenty-five companies responded to the survey. Respondents were primarily small companies each focusing on developing 1 to 3 new antibiotics, focused on pathogens of public health importance. Most have not yet completed any clinical trials. They have reported ranges of discovery and development out-of-pocket costs that appear to be less expensive than other studies of general pharmaceutical research and development (R&D) costs. The duration ranges reported for completing each phase of R&D are highly variable when compared to previously published general pharmaceutical innovation average durations. However, our sample population is small and may not be fully representative of all relevant antibiotic SMEs.

    Conclusions

    The data collected by this study provide important insights and estimates about R&D in European SMEs focusing on antibiotics, which can be combined with other data to design incentives to stimulate antibacterial innovation. The variation implies that costs and durations are difficult to generalize due to the unique characteristics of each antibiotic project and depend on individual business strategies and circumstances.

  • 12859.
    Århammar, Cecilia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Grahn, Alexander
    Vall, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Strömme, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Boman, Mats
    Functionalization of amorphous magnesium carbonate by Atomic Layer Deposition of (3-Aminopropyl)trietoxysilane (APTES) and (3-aminopropyl)trimethoxysilane (APTMS)2016Inngår i: 43rd ICMCTF International conference on Coatings and Thin Films, 2016, Vol. B2-2-8, s. 8-Konferansepaper (Fagfellevurdert)
  • 12860.
    Århammar, Cecilia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialteori.
    Pietzsch, Annette
    MAX-lab, Lunds universitet, Lund.
    Bock, Nicolas
    Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM, USA.
    Holmström, Erik
    Instituto di Fisica, Universidad Austral de Chile, Valdivia, Chile.
    Araujo, Carlos Moyses
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialteori.
    Gråsjö, Johan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaci. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Zhao, Shuxi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Green, Sara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Peery, T
    Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM, USA.
    Hennies, Franz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Mjukröntgenfysik.
    Amerioun, Shahrad
    Sandvik Tooling, R and D, Stockholm.
    Foehlisch, Alexander
    Insitute for Methods and Instrumentation in Synchrotron Radiation Research G-12, Helmhotz-Zentrum Berlin für Materialien und Energie, Berlin, Tyskland.
    Schlappa, Justine
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Schmitt, Thorsten
    Swiss Light Source, Paul Scherrer Institut, Villigen, Schweiz.
    Strocov, Vladimir N
    Swiss Light Source, Paul Scherrer Institut, Villigen, Schweiz.
    Niklasson, Gunnar A
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Wallace, Duane C
    Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM, USA.
    Rubensson, Jan-Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Mjukröntgenfysik.
    Johansson, Börje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialteori.
    Ahuja, Rajeev
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialteori.
    Unveiling the complex electronic structure of amorphous metal oxides2011Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 108, nr 16, s. 6355-6360Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Amorphous materials represent a large and important emerging area of material's science. Amorphous oxides are key technological oxides in applications such as a gate dielectric in Complementary metal-oxide semiconductor devices and in Silicon-Oxide-Nitride-Oxide-Silicon and TANOS (TaN-Al2O3-Si3N4-SiO2-Silicon) flash memories. These technologies are required for the high packing density of today's integrated circuits. Therefore the investigation of defect states in these structures is crucial. In this work we present X-ray synchrotron measurements, with an energy resolution which is about 5-10 times higher than is attainable with standard spectrometers, of amorphous alumina. We demonstrate that our experimental results are in agreement with calculated spectra of amorphous alumina which we have generated by stochastic quenching. This first principles method, which we have recently developed, is found to be superior to molecular dynamics in simulating the rapid gas to solid transition that takes place as this material is deposited for thin film applications. We detect and analyze in detail states in the band gap that originate from oxygen pairs. Similar states were previously found in amorphous alumina by other spectroscopic methods and were assigned to oxygen vacancies claimed to act mutually as electron and hole traps. The oxygen pairs which we probe in this work act as hole traps only and will influence the information retention in electronic devices. In amorphous silica oxygen pairs have already been found, thus they may be a feature which is characteristic also of other amorphous metal oxides.

  • 12861.
    Årling, Oscar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Construction, programming and testing of measurement equipment for microbe culturing in space: Contribution to the MOREBAC experiment, part of the MIST-project2017Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Many different bacteria have essential roles in the process ofrecycling organic waste, making them useful tools when it comes toestablishing artificial ecosystems, a key technology to master inthe expansion of human space travel.In order to further investigate bacteria growth conditions duringspace travel, the MOREBAC experiment was formulated. The objectivewas to design an experimental setup and develop measurementequipment with the capability of confirming successfulresuscitation of freeze-dried bacteria in space by measuringbacteria growth, on-board the student-built MIST-satellite.The experimental setup prototype consisted of an acrylic chipwherein the bacteria would be placed during experiments and anoptical measurements configuration using a photosensor with thepurpose of detecting bacteria cell growth. For experimentalenvironment monitoring, a temperature sensor and a pressure sensorwere calibrated.An Arduino Nano microcontroller was programmed to control allelectrical components during measurements. During the opticaldensity measurements blue dyed water and E.coli bacteria innutrition media were used as test samples.Provided varying blue dye or bacteria cell concentrations, in theform of dilution series and growth-over-time-series, the equipmentproved capable of producing measurements that indicate the opticaldensity of the test sample.Furthermore, a prototype experiment protocol simulating eventsthat will occur in the final experiment design, was implementedand was able to produce real-time monitoring graphs of optical,temperature and pressure measurements, as well as documentation ofall events and measurement data.

  • 12862.
    Årmarker, Anna
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Kihlström, Britta
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Processförbättring inom Scanias reservdelsavdelning: en studie om kommunikationen och arbetsflödet inom POR-processen2019Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The study has been carried out at the spare parts department at Scania AB. The department works with a process called Phase Out Request (POR). The company works according to Lean and in the POR process many bottlenecks arise and production stops when products are phased out. The purpose of the study is to improve the POR process for spare parts at the spare parts department, Scania AB. To achieve the purpose, the following problem formulations have been identified: How can the communication in the POR process be improved? How can the workflow be improved? The theory used is based on workflow and communication, and deals with, among other things, visual control, quality and organizational development and the communication components and problems. Qualitative method has been used to carry out the study and the letter method and in-depth interview have been carried out to collect data. There are visual improvement possibilities within the process and the study contributes to the process being improved with visual clarity such as process map and flow diagram. In addition, concrete improvement proposals have also been developed that can be implemented by the organization in the short term. The proposed solutions can be used in other processes, as organizations should strive for a flow in their operations and improve their communication. Flow in the business and communication are parts that are everywhere and that everyone can benefit from improving.

  • 12863.
    Åsberg, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Deposition of CIGS absorber layer by gas flow sputtering: Initiation of project2013Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The photovoltaic solar cell industry is growing rapidly, but high cost per watt is still an obstacle. Thin film solar cells, especially thin film solar cells using CIGS absorbers that have the highest proven efficiency, have the potential to reduce the cost through cheap manufacturing. Academic research concerning CIGS solar cells has so far been focused on cells with absorber layers deposited by co-evaporation, which can be used to make very high efficiency cells but is a deposition process ill suited for large scale production.

    In this thesis a process for depositing CIGS absorber layers by gas flow sputtering, a deposition technique enabling high rate depositions of low energy particles that is potentially easier to apply to a large scale production, has been outlined. Equipment for CIGS-deposition by gas flow sputtering has been prepared, characteristics of the process have been investigated and ultimately a series of first prototype CIGS absorber layers has been deposited as part of complete solar cells.

    A lot of focus in this thesis is on the practical work and problem solving around the equipment, e.g. pulsed DC power supplies and electrical connections, heating and heating control in a reactive vacuum environment, and on the basic functionality of the gas flow sputter, how process and film properties like deposition rate, thickness uniformity etc. vary with sputter conditions like pressure, gas flow etc.

    Following the process design the first prototype series produced crystalline CIGS absorbers of desired elemental composition and thickness but having rather small grain sizes, while the complete cells exhibited solar cell IV-characteristics but very poor efficiencies.

  • 12864.
    Åsberg, Cay
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Solvärme med säsongslager i Lyckebo2011Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The purpose of this thesis is to investigate and clarify the facts surrounding one of Vattenfall's district heating plants; The "solar field" and associated rock cavern in Lyckebo, Storvreta. The plant was built in the '80s by the formerly municipal utility,Uppsalakraftvärme AB, as an experimental building. A ground water filled cavern would serve as seasonal storage of solar heat from an adjacent solar field.

     

    Since both the energy company and the facility itself has undergone major changes over the past 30 years, there was a great need to gather facts in order to provide a picture of its current condition and potential for continued use. The thesis investigates the plant's history and problems with the rock cavern losses, and how the operation developed. It also presents the calculations regarding the possibilities of again supplementing the facility with solar energy - which is not the case today - as well as the economic conditions for it.

     

    Regarding a re-launch of solar energy, primarily a concentrating solar collector has been studied, as it has the advantages of an integrated control system. The calculations show that an implementation would be modestly profitable as an investment from Vattenfall. A far more successful concept however would be to go for a shareholder owned plant - a Solar cooperative. Such a solution has all the prerequisites to once again make Storvreta known for its solar energy storage, as well as produce a needed portion of goodwill for Vattenfall.

  • 12865.
    Åslund, Anton
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad mekanik, Byggteknik.
    5D-modellering i byggskedet: Med inriktning på anläggningsbranschen2014Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    With those utilities and possibilities we have today, 3D-models should be usted more

    than they are. The posibilities to work further with these models are enormous.

    The purpose with this report is to investigate why the BIM technology isn’t used to

    its fully potential in the construction industry. And also to investige the posibilities to

    implement the technique further by interconnecting the 3D-model to more

    information consisting of 4D-BIM and 5D-BIM. By a comparison between the real

    estate industry and the construction industry produce solutions that can be implied in

    the construction industry.

    The methods that have been used in this operation is a study of literature and

    interviews of experts in the industry. Based on these methods the author has

    concluded several reasons why 5D-modeling is so limited as it is. This area is rather

    undiscovered, few in the industry even thinks of this as a problem, or an area that

    needs improvement, so the investigation in the area is very limited. Besides, the time

    it takes for a person to learn a new working progress is time the person often doesn’t

    have. Plus that the new is frightening, the time it takes to learn the new way is

    unknown and the time it takes to imply it in the projekt is unknown. The way you’ve

    always worked is safe and you know approximitly how long it’s going to take.

    One thing that is notable in the construction industry is that the demands from the

    clients is starting to appear and the competens of the contractors doesn’t exist. And

    there is a fatal chans that the demands will increase much faster than the development

    of competens in the industry. For the industry to keep develop in the right pace, the

    industry must dare to invest in 5D-modeling. By giving priority to learn a more

    efficient way of working, by daring to invest economically in software and education of

    competens and to look at these costs as an investment in the future and not a cost

    for the ongoing projekts.

  • 12866.
    Åslund, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära.
    Requirements on the backup discharge system of spillways2011Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Hydropower is the largest producer of

    renewable electricity in Sweden with a

    yearly mean production of 65TWh. A key

    aspect of hydropower is its’ ability to

    store energy in dams and therefore being

    able to adjust the production to the

    energy consumption. Since each river

    system in Sweden is different each dam

    is unique. The focus on dam safety

    issues has increased in Sweden during

    the last 15 years. SMHI has created more

    accurate flow models and new dam safety

    ideas have been obtained though

    international collaboration. The RIDAS

    guidelines for dam safety govern the

    hydro power companies’ dam safety work.

    Dams are rated after the consequence of

    a dam breach. The consequence class of a

    dam puts demands on the backup system. A

    consequence class 1 dam is to be

    dimensioned to withstand a 10000 year

    flow and is also required to have a

    backup system installed. In accordance

    to the demands set by RIDAS, Fortum have

    decided to do dam investigations called

    FDU on a regular basis. Due to a focus

    on dam safety Fortum are conducting dam

    safety increasing projects on several of

    their dams. Backup systems can be

    designed in many different ways and must

    be customized to fit the properties of

    the dam. By analyzing the river system,

    how the dam is designed and what the

    surroundings look like conclusions about

    what is needed in terms of backup system

    can be drawn.

  • 12867. Åslund, P.
    et al.
    Hägglund, R.Carlsson, L.Isaksson, PerUppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad mekanik.
    Modeling of global and local buckling of corrugatedboard panels loaded in edgewise compression2012Konferanseproceedings (Fagfellevurdert)
  • 12868. Åslund, Pär E.
    et al.
    Hägglund, Rickard
    Carlsson, Leif A.
    Isaksson, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad mekanik.
    An analysis of strain localization and formation of face wrinkles in edge-wise loaded corrugated sandwich panels using a continuum damage model2015Inngår i: International Journal of Solids and Structures, ISSN 0020-7683, E-ISSN 1879-2146, Vol. 56-57, s. 248-257Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper examines the compressive failure mechanism in edge-to-edge loaded corrugated sandwich panels. The formation of face wrinkles is specifically considered. A detailed finite element model of face sheets and web core of a sandwich panel was developed to provide insight on the failure mechanism. A gradient enhanced continuum damage theory was implemented to capture length effects caused by the material microstructure including formation of damage in the face sheets and core. Distributions of strains in the face sheets determined from finite element analysis (FEA) are compared to experimentally measured strains. The predicted location and orientation of the face wrinkle, as indicated by high values of the second principal strain, agrees well with experimental observations. Load vs. out-of-plane deflection curves obtained from FEA with the gradient enhanced damage material model are compared to those obtained from a linear-elastic material model and experimentally determined curves. The gradient enhanced solution gives qualitatively better agreement with experimental results, although the magnitudes of strains are less than those determined experimentally. 

  • 12869.
    Åstrand, Lisa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Implementation of Sub-GHz Real Time Radio2016Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The field of automation and smart devices is currently expanding. As most devices require wireless communication, the market for low budget, low power radios is growing rapidly. Many applications, such as the remote control of machines, have real time requirements with minimal latency. In this report, the market of wireless chips in the sub-GHz region has been investigated in order to give Syntronic AB an insight of the current market. Several key features such as range, data rate and output power were ranked among the available chips. To provide Syntronic with a marketing tool when reaching out to customers in the remote control field, a demonstration prototype (demo) was implemented using one of the radio chips from the list. The demo shows real time requirements with low latency between two wireless nodes. The first node takes movement data from a computer mouse and transmits it to the other node controlling an array of light emitting diodes (LEDs). This report contains the selection of radio configurations, design of a new wireless communications protocol, and implementation of the system in hardware and software. Measurements show a latency of 3.6 ms and a range of approximately 450 m which is regarded satisfactory.

  • 12870.
    Åström, Joakim
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad mekanik, Byggteknik.
    Användandet av mobila enheter med appsystem och appars fackmannamässiga potential inom byggbranshen2014Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    Mobile devices such as tablets and smartphones are quite common in this day. The author of this thesis wanted to know how common these mobile devices are in the building industry and how they are used and what potential an app could have. The author thus conducted an investigation on this matter, mainly in the form of interviews.

    Answers given by the interviews were then used as a basis to survey the usage of mobile devices and the usage of different kinds of apps. An investigation of different apps with the potential to be used by professionals in the building industry has been carried through. Apps which manage such things as scanning documents, measuring distances and handle communication. A further more advanced study of a floor plan making app, called MagicPlan has also been done. The equipment that were used were Samsung Galaxy S2, Apple iPad , Samsung Note 10.1 Tablet, Leica Disto, Leica Scanstation C10, Canon Pixma MP270.

    The results of the examination show that the usages of mobile devices are widely spread in the building industry, however, seldom to its full potential. The results also indicates that the tested apps likely can be used by professionals in some cases.

  • 12871.
    Åström, Karl
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära.
    Productivity Improvements in Assembly: Vertical synchronous generators; Stator Core and Rotor Rim2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
  • 12872.
    Öberg, André
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Konstruktion av demonteringsrigg: För gängade hydraulikcylindrar.2014Independent thesis Advanced level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    Dione kullager AB is a company in Uppsala, which sell industrialmachinecomponents, transmissionsolutions and provides repair serviceof hydraulic components.

    When a hydraulic cylinder is about tobe repaired it needs to bedisassembled. Because hydrauliccylinders usually work in dirtyenvironments and are heavilyworn some types of cylinders arealmost impossible to disassemble.Today the disassemble is made by hand,which means extra work for themechanics. In order to facilitate thedismantling of this type of cylindersa machine is to be developed for thispurpose and this is where this thesisbegins.

    The thesis has been organized in threephases: Literature study in whichfacts and theories are acquired.Concept generation in which differentconcepts, calculations, and solutionswere identified and selected. Thedesign phase where all the differentconcepts of components were assembledand simulated in SolidWorks. Similarstructures have also been studied inorder to identify necessary functions.

    The thesis resulted in a structurewhich is believed to meet therequirements. The design is flexiblein adjustment and easy to modify fordifferent tools. The construction issuitable for using the engine packageand 3-jaw chuck that Dione previouslypurchased.

  • 12873.
    Öberg, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära.
    Lindeberg, Oscar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Energikartläggning: av LKAB Logistik, samt energieffektiviseringsåtgärder2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    This thesis concerns an energy audit of LKAB Logistics. According toswedish law a company the size of LKAB are required to make an energyaudit every four year. LKAB Logistics mainly transports refined ironore products between mines and harbours along the train track"Malmbanan". They also store iron ore products and load boats in theharbours in Narvik and Luleå. These kinds of operations have a highdemand for energy. This demand is met mostly with electricity.However, oil, gas, diesel and district heating are also consumed tomeet the energy demand. In total LKAB Logistics consume around 191GWh, where roughly 75% is of electricity. With such high demand,savings around 1-2% makes a significant difference, and there areopportunities and incentives to improve energy efficiency.Implementing staff that are responsible for energy work, makinginvestments in new electrical motors and more energy-efficient windowsare a few examples. Higher priority on energy saving and continuedprogress for a more efficient work place will most likely benefit thecompany's environmental goals and economy.

  • 12874.
    Öberg, Tommy
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    A circuit for contact monitoring in electrocardiography1982Inngår i: IEEE Transactions on Biomedical Engineering, ISSN 0018-9294, E-ISSN 1558-2531, Vol. BME-29, nr 5Artikkel i tidsskrift (Fagfellevurdert)
  • 12875.
    Öberg, Tommy
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Robust detection applied to phase modulated signals1989Konferansepaper (Fagfellevurdert)
  • 12876.
    Öberg, Tommy
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Use of residue arithmetic for resolving ambiguity in phase measruements1989Inngår i: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 38, nr 5, s. 1007-1009Artikkel i tidsskrift (Fagfellevurdert)
  • 12877.
    Öberg, Viktor
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi.
    Johansson, Malin B
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi.
    Johansson, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi.
    Tuning Size and Composition in Cubic AgBiS2 CQDs for Solar CellsManuskript (preprint) (Annet vitenskapelig)
  • 12878. Öberg, Å.
    et al.
    Kassman, Åsa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    André, Benny
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Wiklund, Urban
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Lindquist, M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Lewin, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Oorganisk kemi.
    Jansson, Ulf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Oorganisk kemi.
    Högberg, Hans
    Joelsson, T.
    Ljungcrantz, H.
    Conductive nanocomposite ceramics as tribological and electrical contact materials2010Inngår i: European Physical Journal: Applied physics, ISSN 1286-0042, E-ISSN 1286-0050, Vol. 49, nr 2, s. 22902-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Conductive ceramics have widespread use in many industrial applications. One important application for such materials is electrical contact technology. Over the last few years, a new class of nanocomposite ceramic thin film materials has been developed with contact coatings as one key objective. This family of materials has proven to combine the favorable contact properties of metals, such as low electrical and thermal resistivity, and high ductility, with those of ceramics such as low friction and wear rate, high chemical integrity and good high-temperature properties. Furthermore, it is also found that the tribological properties of such materials can be tailored by alloying thus creating a triboactive system. The technology is now industrialized, and a practical example of a contact system utilizing a nanocomposite coating for improved performance is given.

  • 12879.
    Öberg, Åke
    et al.
    ABB Corporate Research.
    Johansson, Erik
    ABB Corporate Research.
    Arnell, Sylva
    ABB Corporate Research.
    Kassman Rudolphi, Åsa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    On the self-healing of silver contacts2016Inngår i: Proceedings - 28th International Conference on Electric Contacts, 2016, s. 265-270Konferansepaper (Fagfellevurdert)
  • 12880. Öberg, Åke
    et al.
    Kassman Rudolphi, Åsa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Wiklund, Urban
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    André, Benny
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Lewin, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Oorganisk kemi.
    Jansson, Ulf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Oorganisk kemi.
    Conductive nanocomposite ceramics as tribological and electrical contact materials2008Inngår i: International Conference on Electrical Contacts, ICEC 2008, 2008Konferansepaper (Fagfellevurdert)
  • 12881.
    Ödeen, S
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap. Institutionen för teknikvetenskaper, Hållfasthetslära. Hållfasthetslära.
    Lundberg, B
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för materialvetenskap. Institutionen för teknikvetenskaper, Hållfasthetslära. Hållfasthetslära.
    Determination of complex modulus from measured end-point accelerations of an impacted specimen1993Inngår i: Journal of Sound and Vibration, Vol. 165, s. 1-8Artikkel i tidsskrift (Fagfellevurdert)
  • 12882.
    Ögger, Julius
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Ströberg, Viktor
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Processoptimering av tungspackelproduktion2017Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    This degree project was performed at Sherwin-Williams in Märsta, Sweden over a period of ten weeks. The purpose of the work was to optimize the manufacturing process of heavy fillers due to a problem with achieving consistent quality. An optimization of the process would lead to a larger produced volume and thus increased sales. This would also help provide a better insight in all the parts of the manufacturing process. The company uses an index called OTMIS that describes how many of the products that are approved in the quality control directly after being manufactured. A higher OTMIS-index would result in a lowered total process time as it would lead to fewer time-consuming adjustments of non-approved filler batches.

    The work is based on a literature study and lectures in filler production to gain a basic understanding of how the production works. Daily observations of the manufacturing process led to the design of experiments being made for own laboratory tests. The purpose of these tests was to identify the parameters that had the greatest impact on the properties of the filler and how these should be controlled.

    Using the MODDE software, the key variables and their impact on the filler’s final quality and utility could be found and optimized. The time between the completion of the manufacturing process and the quality control, and how much variation there was in the amount of filling material used to give the filler the correct rheology proved to have the greatest impact on the results. After developing an analysis of possible sources of errors and how much they affected the result, a plan of solutions was submitted for continued improvement work. The proposals in this plan focus on lowering the average process time by introducing new routines for control, changing the manufacturing process as per the filling material’s effect, improved documentation of the manufacturing process and striving for a longer term planning process prior to manufacturing.

  • 12883.
    Ögren, Jim
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    PLL design for inverter grid connection: Simulations for ideal and non-ideal grid conditions2010Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    In this report a phase locked loop (PLL) system for grid voltage phase tracking has been investigated. The grid voltage phase angle contains critical information for connecting a power plant, such as a wave energy converter, to the grid. A synchronous reference frame PLL system with PI-regulator gains calculated with the symmetrical optimum method has been designed and simulations in SIMULINK have been made. For ideal grid conditions the phase angle was tracked fast and accurate. For non-ideal conditions the phase angle was tracked but with less accuracy, due to slow dynamics of the system, but still within acceptable margins. In order to test this system further it has to be implemented in a control system and tested when connected to the grid.

  • 12884.
    Ögren, Jim
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära.
    Simulation of a Self-bearing Cone-shaped Lorentz-type Electrical Machine2013Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Self-bearing machines for kinetic energy storage have the advantage of integrating the magnetic bearing in the stator/rotor configuration, which reduces the number of mechanical components needed compared with using separated active magnetic bearings. This master's thesis focus on building a MATLAB/Simulink simulation model for a self-bearing cone-shaped Lorenz-type electrical machine. The concept has already been verified analytically but no dynamic simulations have been made. The system was modeled as a negative feedback system with PID controllers to balance the rotor. Disturbances as signal noise, external forces and torques were added to the system to estimate system robustness. Simulations showed stability and promising dynamics, the next step would be to build a prototype. 

  • 12885.
    Ögren, Jim
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Jafri, Hassan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Leifer, Klaus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Ziemann, Volker
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Surface Characterization and Field Emission Measurements of Copper Samples inside a Scanning Electron Microscope2016Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Vacuum breakdown in normal-conducting accelerating structures is a limiting factor for high gradient acceleration.Many aspects of the physics governing the breakdown process and its onset are yet to be fully understood. At Uppsala University we address these questions with an in-situ experi-mental setup mounted in an environmental scanning electron microscope. It consists of a piezo motor driven tungsten needle and a sample surface mounted on a piezo stage, allowing for nano-meter 3D-position control. One of the piezomotors controls the needle-sample gap while the two otherscan across the surface. A DC-voltage up to 1 kV is  applied across the gap and field emission currents from a coppersurface are measured with an electrometer. Here we presentthe setup and some initial results.

  • 12886.
    Öhlander, Björn
    et al.
    Luleå tekniska universitet, Geovetenskap och miljöteknik.
    Weihed, Pär
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper. Luleå tekniska universitet.
    Proterozoic mineralizations associated with granitoids in northern Sweden: Excursion guide no 71986Inngår i: 7th IAGOD symposium and Nordkalott project meeting / [ed] Ebbe Zachrisson, Sveriges Geologiska Undersökning , 1986Konferansepaper (Annet vitenskapelig)
  • 12887.
    Öhlund, Dennis
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Johansson, Robert
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Kylcontainerns teknologiska utveckling: Innovation och utveckling av containerteknologin för transport av kylda varor2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
  • 12888.
    Öhlund, Dennis
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Johansson, Robert
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Paketering av väredepåsar: Automatisering av en manuell process2012Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Detta examensarbete syfta på att automatisera en paketeringsprocess av mynt som idag utförs manuellt av personalen på företaget Loomis. Det automatiserade konceptet som kommer presenteras för företaget skall kortfattat klara av att paketera deras värdepåsar med myntenheter.

    Projektet startar med att skapa en förståelse för vad som skall utföras på företaget och vilka problem som finns idag. I arbetets första fas utförs samtal med behörig personal där noggrann dokumentation och granskning om hur arbetsmetodiken utförs för tillfället.

    Efter att tillräckligt med fakta hade samlats började nästa fas med informationsinsamling. Olika automationstillverkares hemsidor studerades för att få mer kunskap om olika lösningar. Även ett studiebesök utfördes på ett företag som använder maskiner och robotar i deras produktionslinor.

    När tillräckligt med information och kunskap hade samlats inom det berörda området så började enklare skisser på en helhetslösning att ritas upp. Flera olika koncept genererades men efter noggrann jämförande där konceptens för-­‐ och nackdelar ställdes mot varandra så bestämdes ett koncept. Det konceptet som valdes uppfyllde de ställda kraven bäst.

    Nästa steg i projektet genomfördes genom att olika standardkomponenter studerades och valdes. Olika dellösningar i helhetskonceptet studerades mer noggrant och olika förslag skissades upp. Slutligen bestämdes vilka delkoncept som skulle ingå i automationslösningen.

    När alla koncept till de specifika dellösningarna som ingår i helhetslösningen hade valts, började konstruktionsprocessen. Denna process utfördes i 3D-­‐programmet Solid Works och resultatet presenteras närmare i kapitel 6.

    Det färdigställda konceptet på automationslösningen uppfyller de ställda kraven som var satta på produkten. Om företaget väljer att gå vidare med detta koncept kommer kostnadsbesparingar göras genom minskad personalaktivitet. Men det viktigaste bidraget som automationslösningen kan bidrar till är att den förbättra arbetsmiljön för de anställda genom att arbetsskador som uppstod med tunga lyft nu kan elimineras. 

  • 12889.
    Öhman, Ben Sebastian
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Energy efficiency investments in the commercial real estate business: A study of decision drivers on the Swedish market2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The International Energy Agency has stated that it is more sustainable to improve the energy efficiency of already existing buildings than increasing the national energy production to provide inefficient buildings with even more energy, which would result in that an increased amount of resources required to power the existing energy inefficient building stock. Taken into consideration that buildings in Sweden consume about 40% of Sweden’s final energy consumption and count for about 36% of the total greenhouse gas emissions it becomes evident that in order to decrease Sweden’s carbon foot print, it is important to understand real estate investors decision-making process. The aspiration is to provide stakeholders both on a micro and macro level with a better understanding of the real estate investors decision making process. This will enable companies (micro level) in the field to better customize their value propositions and there by enable companies to contribute to decreasing the primary energy consumption of buildings in Sweden. The macro level, referring to governmental institutions, will be provided with a better understanding of what kind of measures can be taken, to increase investments into buildings energy efficiency. It could be found from the literature reviewed for the study that there is a gap in research what comes to the Swedish market. Majority of the existing literature covers bigger markets e.g. the USA and UK but very little or if at all the Swedish market. During the literature study an existing framework on decision drivers for real estate investors was developed. The study uses mixed method consisting of qualitative and quantitative methods to answer the research questions. The study showed that the most prominent drivers on the Swedish market were the customers strategic decisions, environmental and energy certificates, reporting protocols, investment horizon, rental agreements, internal investment policies decreased property costs and building specific characteristics. It was found that the Swedish real estate investors experience very little pressure from the government to increase the energy efficiency of their buildings. It was also found that governmental subsidies are more considered a gamble than an encouragement to invest in energy efficiency due to long processing times and heavy bureaucracy.

  • 12890.
    Öhman, Caroline
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Carlsson, Elin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Ginebra, Maria Pau
    Biomaterials, Biomechanics and Tissue Engineering Group, Dept. of Materials Science and Metallurgy, Technical University of Catalonia.
    Persson, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Engqvist, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Porosity prediction of calcium phosphate cements2013Konferansepaper (Fagfellevurdert)
  • 12891.
    Öhman, Caroline
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Carlsson, Elin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Ginebra, Maria Pau
    Biomaterials, Biomechanics and Tissue Engineering Group, Dept. of Materials Science and Metallurgy, Technical University of Catalonia.
    Persson, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Engqvist, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Prediction of porosity in hydroxyapatite and brushite cements2013Konferansepaper (Fagfellevurdert)
  • 12892.
    Öhman, Caroline
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Espino, Daniel M.
    School of Mechanical Engineering, University of Birmingham, Birmingham, UK.
    Baleani, Massimiliano
    Laboratorio di Tecnologia Medica, Istituto Ortopedico Rizzoli, Italy.
    Erani, Paolo
    Laboratorio di Tecnologia Medica, Istituto Ortopedico Rizzoli, Italy.
    Juszczyk, Mateusz
    Laboratorio di Tecnologia Medica, Istituto Ortopedico Rizzoli, Italy.
    Maccarrone, Pierro G.
    Laboratorio di Tecnologia Medica, Istituto Ortopedico Rizzoli, Italy.
    Falco, Luigi
    Laboratorio di Tecnologia Medica, Istituto Ortopedico Rizzoli, Italy.
    Toni, Aldo
    Laboratorio di Tecnologia Medica, Istituto Ortopedico Rizzoli, Italy.
    AN EXPERIMENTAL METHOD TO CHARACTERISE KNEE STABILITY: PRELIMINARY TESTS WITH A PORCINE MODEL2012Konferansepaper (Fagfellevurdert)
  • 12893.
    Öhman, Caroline
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Hulsart-Billström, Gry
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Particelli, Francesca
    Laboratorio di Tecnologia Medica, Istituto Ortopedico Rizzoli, Italy.
    Baruffaldi, Fabio
    Laboratorio di Tecnologia Medica, Istituto Ortopedico Rizzoli, Italy.
    Larsson, Sune
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Engqvist, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Premixed calcium phosphate cement as a carrier of bone morphogenetic protein2013Konferansepaper (Fagfellevurdert)
  • 12894.
    Öhman, Caroline
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Nouhi, Shirin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Hulsart-Billström, Gry
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Engqvist, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Larsson, Sune
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Facilitating separation of bone from bonelike materials in micro-computed tomography images2014Konferansepaper (Fagfellevurdert)
  • 12895.
    Öhman, Caroline
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Unosson, Johanna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Carlsson, Elin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Ginebra, Maria-Pau
    Technical University of Catalonia, Spain.
    Persson, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Engqvist, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Porosity prediction of calcium phosphate cements based on chemical composition2015Inngår i: Journal of materials science. Materials in medicine, ISSN 0957-4530, E-ISSN 1573-4838, Vol. 26, nr 7, artikkel-id 210Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The porosity of calcium phosphate cements has an impact on several important parameters, such as strength, resorbability and bioactivity. A model to predict the porosity for biomedical cements would hence be a useful tool. At the moment such a model only exists for Portland cements. The aim of this study was to develop and validate a first porosity prediction model for calcium phosphate cements. On the basis of chemical reaction, molar weight and density of components, a volume-based model was developed and validated using calcium phosphate cement as model material. 60 mol% beta-tricalcium phosphate and 40 mol% monocalcium phosphate monohydrate were mixed with deionized water, at different liquid-to-powder ratios. Samples were set for 24 h at 37 degrees C and 100 % relative humidity. Thereafter, samples were dried either under vacuum at room temperature for 24 h or in air at 37 degrees C for 7 days. Porosity and phase composition were determined. It was found that the two drying protocols led to the formation of brushite and monetite, respectively. The model was found to predict well the experimental values and also data reported in the literature for apatite cements, as deduced from the small absolute average residual errors (<2.0 %). In conclusion, a theoretical model for porosity prediction was developed and validated for brushite, monetite and apatite cements. The model gives a good estimate of the final porosity and has the potential to be used as a porosity prediction tool in the biomedical cement field.

  • 12896.
    Öhman, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik.
    Standardisering och optimering av packningsprocess2013Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    This is a thesis performed at GEMS PET Systems AB in Uppsala. GEMS PET Systems AB is a company within GE Healthcare. GEMS PET Systems develops and manufactures equipment for manufacturing of radioactive isotopes for PET which is a scanner used in medical applications. The systems includes an accelerator of cyclotron type and other support equipment. One system is shipped in two or three containers depending on order configuration. The main difference in these order configurations is whether radiation shielding will be included in the system or not. If not, there will be a radiation shielding concrete bunker built on site where the systems will be housed. The problem that is to be solved is that some of the components being shipped lacks sufficient shipping boxes which needs to be created. Once created these componenets will need more space in the containers which in turn creates the need for a new cargo plan for each container. This to make sure the loading process is efficient. Along with the cargoplanning a loading instruction is to be created. Using CAD the existing cargo along with the new crates was drawn and a cargoplan for each container. The outcome of this work were new shipping crates and cargoplans for each container.

  • 12897.
    Öhman Mägi, Caroline
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Holub, Ondrej
    School of Mechanical Engineering, University of Leeds, UK.
    Hall, Richard M.
    School of Mechanical Engineering, University of Leeds, UK.
    Persson, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    A review of the relationships between density and mechanical properties of vertebral trabecular bone2017Konferansepaper (Fagfellevurdert)
  • 12898.
    Öhman Mägi, Caroline
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Holub, Ondrej
    School of Mechanical Engineering, University of Leeds, UK.
    Hall, Richard M
    School of Mechanical Engineering, University of Leeds, UK.
    Persson, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Predicting the mechanical properties of vertebral trabecular bone - a review2017Konferansepaper (Fagfellevurdert)
  • 12899.
    Öhman, Sebastian
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Wear on Alumina Coated Tools and the Influence of Inclusions when Turning Low-Alloy Steels: Master Thesis - Chemical Engineering2016Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    In this master thesis, performed at Sandvik Coromant Västberga (Stockholm), a comprehensive study has been made to investigate the wear on textured alumina (Inveio™) coated cutting tools when turning low-alloy steels. Specifically, wear studies have been made on tools’ rake faces when turning two separate batches of SS2541, after an initial turning time of 4 min. A particular focus has been given to elucidate what particular role the inclusions might have for the wear of the alumina coating onthe tools. Evaluation of tool wear has been made by employing several different analytical techniques, such as LOM, SEM, Wyko, Auger-spectrometry (AES), EPMA and XRD.

    The results shows that the arisen wear marks on both tested tool types may be divided into three separate and highly distinguishable wear zones, denoted here in thiswork as “wear bands”. Largest amount of wear tended to occur initially at the topmost part of the 3rd wear band. This was true for both tested tool types. This area demonstrated a characteristic 'lamellar' wear pattern, composed of narrow andstructured ridges.

    All the tools tested demonstrated the adhesion of workpiece materials of various composition that formed into smeared layers in these formed ridges. Depth-profiling Auger-spectrometry revealed that a significant amount of calcium was present in the machined alumina coating layers. This suggests that a reaction between the calcium-containing inclusions found in the steel and the aluminacoating layer had occurred during the performed turning tests.These results arecontradictory to the general belief that alumina is chemical inert during machiningand has previously, to the authors knowledge, not yet been published.

    Based on the results from this thesis and from a literature review concerning thebehavior of α-alumina during deformation, a new theoretical wear model has been developed. In this model, it is emphasised that the sliding of hard inclusions from the steel may activate pyramidal slip systems in the textured alumina coating. This causes a nano-crystallisation and/or amorphisation in the topmost part of the coating, which facilitates the further wear of these coated tools.

  • 12900.
    Öhr, Jonas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Anti-windup and Control of Systems with Multiple Input Saturations: Tools, Solutions and Case Studies2003Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    Control of linear systems with saturating actuators are considered and anti-windup compensators for multiple-input multiple-output systems, and robust, almost time-optimal controllers for double integrators with input amplitude saturations, are proposed.

    Windup effects are defined and anti-windup compensators aiming at minimizing the windup effects are proposed. The design is based on 1) linear quadratic (LQ) optimization techniques and 2) heuristic design using Nyquist-like techniques and pole-placement techniques.

    A root-locus like technique that can, approximately, foretell possible directional problems that may be present in MIMO systems with input saturations, and that can be used for design of anti-windup compensators and for selection of appropriate static directional compensators, is proposed.

    The problem of control of double integrators via saturating inputs is addressed and a robust piece-wise linear controller that gives almost time-optimal performance is suggested. It is shown that time optimal control of a double integrator via an input amplitude limiter, is equivalent to time-optimal control of a single integrator having a rate limiter at the input. One such application, concerning control of hydraulic cylinders in container crane systems, is presented. An extension of the controller, allowing synchronous control of two integrators with input rate limitations, is proposed.

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