On condition-based maintenance for machine components

The goal of condition-based maintenance (CBM) is to base the decisions whether or not to perform maintenance on information collected from the machine or component of interest. A condition-based maintenance tool should be able to diagnose if the component of interest is in a state of failure but the ultimate goal of a CBM tool is to be able to estimate time until failure, either in terms of remaining useful life (RUL) or estimated time to failure (ETTF). Therefore a CBM tool should have both diagnostic and prognostic features. This master’s thesis was carried out at a company within the packaging industry and the goal was to implement a CBM tool with the possibility to estimate RUL for a set of critical components which could serve as a base for further development within the company. The selection of components to focus on was part of the thesis as well. The process of implementing CBM with prognostic functionality was more difficult than expected and the goal of estimating RUL was not met for any of the components, but the work that has been done forms a basis for further development. Thus, this thesis will serve as a pre-study on developing CBM and contains information of what is required in order to be successful

Migration of Legacy Systems in New Public Management – the Swedish Rescue Services Incident Reporting System

The Swedish Rescue Services are migrating from an incident report system to a fully-fledged incident learning system, as part of new public management strategies. The migration process has been studied in an effort to identify challenges and complexities that can offer advice for future system migration projects. The system migration objectives expressed by the central agency leading the studied migration process clearly aimed at implementing double-loop learning in the organizations. The study reveals that in practice this objective has been lost along the way, with the agency in reality focusing more on cosmetic changes, such as terminology, attributes and labels. Meanwhile end-users expressed different and concrete needs, requiring new functionality, process improvements and organizational development. The study highlights the importance of early, active user involvement in the migration process for dual use legacy systems, to avoid losing explicitly articulated high-level objectives, such as improved performance and dual-use of the system

Nonproper intersection products and generalized cycles

We develop intersection theory in terms of the B-group of a reduced analytic space. This group was introduced in a previous work as an analogue of the Chow group; it is generated by currents that are direct images of Chern forms and it contains all usual cycles. However, contrary to Chow classes, the B-classes have well-defined multiplicities at each point. We focus on a B-analogue of the intersection theory based on the Stuckrad-Vogel procedure and the join construction in projective space. Our approach provides global B-classes which satisfy a Bezout theorem and have the expected local intersection numbers. We also introduce B-analogues of more classical constructions of intersections using the Gysin map of the diagonal. These constructions are connected via a B-variant of van Gastel\u27s formulas. Furthermore, we prove that our intersections coincide with the classical ones on cohomology level

Earned Value Management - Ett projektstyrningsinstrument mellan FMV och Kockums -

Sammanfattning Uppsatsens titel: Earned Value Management – Ett projektstyrningsinstrument mellan FMV och Kockums. Seminariedatum: 2007-06-05 Ämne/Kurs: FEK 582 Kandidatuppsats, 10 poäng Författare: Dennis Andersson, Anders Ellström, Viktor Tornberg Handledare: Per Magnus Andersson, Olof Arwidi Nyckelord: Projektstyrning, projekt, Earned Value, Earned Value Manage¬ment, EVM. Syfte: Syftet med denna uppsats är att beskriva och analysera Earned Value Management (EVM) som projektstyrningsinstrument mellan Försvarets materielverk (FMV) och Kockums vid halvtids¬moderniseringen (HTM) av minröjningsfartyg Landsort. Metod: Kvalitativa intervjuer har gjorts med respondenter som har ledande projektbefattningar inom FMV och Kockums. Omfattande litt¬eratur¬studier inom området har bedrivits utav en deduktiv karaktär. Teori: Inledningsvis presenteras generella uppfattningar om projekt¬styrning på ett överskådligt vis. Vi beskriver huvudteorin EVM samt även jämförande teorier såsom Balanced Scorecard samt Målkostnadskalkylering. FMV:s handbok inom projekt¬styrning genom EVM presenteras. Empiri: Projektet beskrivs utifrån sin kontext. Projektets aktörer och dess verksamhet presenteras för att ge en bakgrund till valt fallprojekt. Redovisning av de kvalitativa intervjuerna sker som en samman¬ställning av samtliga respondenters svar. Slutsatser: Här sammanställer vi de slutsatser vi dragit samt kopplar hur EVM som styrinstrument används i vårt fallprojekt. Vi belyser de problem som vi funnit relevanta samt klargör de fördelar vi tycker instrumentet frambringar

Inline-tandem purification of viruses from cell lysate by agarose-based chromatography

An efficient chromatography-based virus purification method has been developed and validated for the nonpathogenic infectious virus PRD1. Compared to the conventional method that consists of relatively time-consuming and labour-intensive precipitation and density gradient ultracentrifugation steps, the method developed here is performed in a single flow using tandem-coupled anion exchange and size exclusion chromatography (AIEX-SEC) columns. This inline approach helps to minimize the loss of virus in the process and streamlines time consumption, since no physical transfer of the sample is required between purification steps. In the development process, sample feed composition, dynamic binding capacity and elution conditions for the AIEX resin as well as different exclusion limits for SEC resins were optimized to achieve maximal yield of pure infectious viruses. Utilizing this new approach, a high-quality virus sample was produced from a lysate feed in 320 min with a total yield of 13 mg purified particles per litre of cell lysate, constituting a 3.5-fold yield increase as compared to the conventional method, without compromising the high specific infectivity of the product (6 x 1012 to 7 x 10(12) pfu/mg of protein). The yield of infectious viruses of the lysate feed was 54%. The easy scalability of chromatography-based methods provide a direct route to industrial usage without any significant changes needed to be made to the purification regime. This is especially interesting as the method has high potential to be used for purification of various viruses and nanoparticles, including adenovirus.Peer reviewe

Increased immunogenicity and protective efficacy of influenza M2e fused to a tetramerizing protein

The ectodomain of the matrix 2 protein (M2e) of influenza A virus represents an attractive target for developing a universal influenza A vaccine, with its sequence being highly conserved amongst human variants of this virus. With the aim of targeting conformational epitopes presumably shared by diverse influenza A viruses, a vaccine (M2e-NSP4) was constructed linking M2e (in its consensus sequence) to the rotavirus fragment NSP4(98-135); due to its coiled-coil region this fragment is known to form tetramers in aqueous solution and in this manner we hoped to mimick the natural configuration of M2e as presented in membranes. M2e-NSP4 was then evaluated side-by-side with synthetic M2e peptide for its immunogenicity and protective efficacy in a murine influenza challenge model. Here we demonstrate that M2e fused to the tetramerizing protein induces an accelerated, augmented and more broadly reactive antibody response than does M2e peptide as measured in two different assays. Most importantly, vaccination with M2e-NSP4 caused a significant decrease in lung virus load early after challenge with influenza A virus and maintained its efficacy against a lethal challenge even at very low vaccine doses. Based on the results presented in this study M2e-NSP4 merits further investigation as a candidate for or as a component of a universal influenza A vaccine

Genetic identification of unique immunological responses in mice infected with virulent and attenuated Francisella tularensis

Francisella tularensis is a category A select agent based on its infectivity and virulence but disease mechanisms in infection remain poorly understood. Murine pulmonary models of infection were therefore employed to assess and compare dissemination and pathology and to elucidate the host immune response to infection with the highly virulent Type A F. tularensis strain Schu4 versus the less virulent Type B live vaccine strain (LVS). We found that dissemination and pathology in the spleen was significantly greater in mice infected with F. tularensis Schu4 compared to mice infected with F. tularensis LVS. Using gene expression rofiling to compare the response to infection with the two F. tularensis strains, we found that there were significant differences in the expression of genes involved in the apoptosis pathway, antigen processing and presentation pathways, and inflammatory response pathways in mice infected with Schu4 when compared to LVS. These transcriptional differences coincided with marked differences in dissemination and severity of organ lesions in mice infected with the Schu4 and LVS strains. Therefore, these findings indicate that altered apoptosis, antigen presentation and production of inflammatory mediators explain the differences in pathogenicity of F. tularensis Schu4 and LVS

Ecosystem services of collectively managed urban gardens : exploring factors affecting synergies and trade-offs at the site level

Collective management of urban green space is being acknowledged and promoted. The need to understand productivity and potential trade-offs between co-occurring ecosystem services arising from collectively managed pockets of green space is pivotal to the design and promotion of both productive urban areas and effective stakeholder participation in their management. Quantitative assessments of ecosystem service production were obtained from detailed site surveys at ten examples of collectively managed urban gardens in Greater Manchester, UK. Correlation analyses demonstrated high levels of synergy between ecological (biodiversity) and social (learning and well-being) benefits related to such spaces. Trade-offs were highly mediated by site size and design, resulting in a tension between increasing site area and the co-management of ecosystem services. By highlighting synergies, trade-offs and the significance of site area, the results offer insight into the spatially sensitive nature of ecosystem services arising from multi-functional collectively managed urban gardens