Uppföljning av planerat skotningsavstånd med hjälp av geografisk informationsteknologi (GIT)

The cost of forwarding corresponds to about one tenth of the forestry industries raw material cost. This gives a motive to do good follow-ups to get a good overview of the forwarding distance and, thus, enable improvements. Follow-ups are also justified by the possibility to make more accurate calculations of the harvesting costs, if better estimations of forwarding distance are achieved. Today (2009) Stora Enso has GPS and vehicle-computers in most of their forwarders. These are used mainly for the forwarder to follow the tracks of the harvester and for the planning leader to see how the forwarder has been driving within the stand. However, the techniques have also other possible uses. The objective of this Master thesis was to evaluate the planned forwarding distance against the actual forwarding distance in thinned stands and to come up with a method for calculating the actual forwarding distance in GIS-environment. The data collected was planned forwarding distance (plus the written instructions to the machine operators), odometer forwarding distance and the tracks created by the GPS during the forwarders work. The tracks were then worked up in ArcGIS 9.3 to get a more correct forwarding distance. The planned forwarding distance was evaluated against actually recorded forwarding distance based on odometric and on ArcGIS calculations. The results show that the planned forwarding distance is substantially underestimated and should be increased by a higher winding coefficient than today (1, 15). The results also indicate that the follow-ups by odometer could be replaced by follow-ups made by the forwarding distance calculated in ArcGIS. However, a condition to make it possible to do the follow-ups in ArcGIS with a reasonable work effort is that there must be precise restrictions on how and when GPS recordings should be done during the forwarding work

Rim-to-Rim Wearables at the Canyon for Health (R2R WATCH): Physiological, Cognitive, and Biological Markers of Performance Decline in an Extreme Environment

Success in extreme environments comes with a cost of subtle performance decrements that if not mitigated properly can lead to lifethreatening consequences. Identification and prediction of performance decline could alleviate deleterious consequences and enhance success in challenging and high-risk operations. The Rim-to-Rim Wearables at the Canyon for Health (R2R WATCH) project was designed to examine the cognitive, physiological, and biological markers of performance decline in the extreme environment of the Grand Canyon Rim-to-Rim (R2R) hike. The study utilized commercial off-the-shelf cognitive and physiological monitoring techniques, along with subjective self-assessments and hematologic measurements to determine subject performance and changes across the hike. The multiyear effort collected these multiple data streams in parallel on a large sample of participants hiking the R2R, leading to a rich and complex data set. This article describes the methodology and its evolution as devices and measurements were assessed after each data collection event. It also highlights a subset of the patterns of results found across the data streams. Subsequent work will draw on this data set to focus on building more sophisticated, predictive statistical models and dive deeper into specific analyses (such as the physiological and biological profiles of hikers who were left behind by their hiking partners)

Charge compensation for NADPH oxidase activity in microglia in rat brain slices does not involve a proton current

The membrane properties of isolated cultured microglia have been extensively studied but it is important to understand their properties in situ, where they protect the brain against infection, but also contribute to neurodegenerative diseases. Microglia and macrophages attack bacteria by generating reactive oxygen species, a process which involves NADPH oxidase pumping electrons out across the cell membrane. The resulting inward current evokes a depolarization, which would inhibit the activity of the NADPH oxidase if there were no charge-compensating current which moves positive charge out across the membrane. The mechanism of this charge compensation is controversial. In neutrophils and in cultured microglia a depolarization-activated H+ conductance has been proposed to provide charge compensation, and also to remove protons generated intracellularly by the NADPH oxidase. Alternatively, a depolarization-activated K+ conductance has been proposed to mediate charge compensation. Here we show that in microglia, either in the resting state or when activated by the bacterial coat component lipopolysaccharide, both in acute and in cultured hippocampal slices, no significant H+ current is detectable. This implies that the membrane properties of microglia in their normal cellular environment differ from those of cultured microglia (similarly, microglia generated a current in response to ATP but, unlike in culture, not to glutamate or GABA). Furthermore, the K+ current (Kv1.3) that is activated by lipopolysaccharide is inactivated by depolarization, making it unsuitable for mediating charge compensation on a long time scale at positive voltages. Instead, charge compensation may be mediated by a previously undescribed non-selective cation current

VSOP/Hv1 proton channels sustain calcium entry, neutrophil migration, and superoxide production by limiting cell depolarization and acidification

Neutrophils kill microbes with reactive oxygen species generated by the NADPH oxidase, an enzyme which moves electrons across membranes. Voltage-gated proton channels (voltage-sensing domain only protein [VSOP]/Hv1) are required for high-level superoxide production by phagocytes, but the mechanism of this effect is not established. We show that neutrophils from VSOP/Hv1−/− mice lack proton currents but have normal electron currents, indicating that these cells have a fully functional oxidase that cannot conduct protons. VSOP/Hv1−/− neutrophils had a more acidic cytosol, were more depolarized, and produced less superoxide and hydrogen peroxide than neutrophils from wild-type mice. Hydrogen peroxide production was rescued by providing an artificial conductance with gramicidin. Loss of VSOP/Hv1 also aborted calcium responses to chemoattractants, increased neutrophil spreading, and decreased neutrophil migration. The migration defect was restored by the addition of a calcium ionophore. Our findings indicate that proton channels extrude the acid and compensate the charge generated by the oxidase, thereby sustaining calcium entry signals that control the adhesion and motility of neutrophils. Loss of proton channels thus aborts superoxide production and causes a severe signaling defect in neutrophils

Utveckling av akustiska simuleringsmetoder för avgassystem

Noise pollution is a growing concern due to its harmfulness to human health. Heavy vehicles powered by internal combustion engines stands for a major part of the environmental noise, why noise reduction is an increasing priority in enginve development. Within this study, an optimization problem is posed in order to minimize acoustic output without impairing the engine's overall performance. In our quest to diversify out noise reduction strategies, innovative ways of investigating this complex subject are essential. Here, we use simulations to investigate the possibility to reduce noise by component settings, as well as methods available to achieve that. Regarding the methods, the results indicates that a built in optimization tool within the simulation software used works well, despite the high complexity of the problem. A significant noise reduction is achieved when adjusting the settings of two of the parameters studied. This is a first attempt to tackle noise reduction in internal combustion engines by component settings. From the promising results, further improvements are expected as the simulation methods are refined and more components can be investigated accurately.Bullerreducering är en allt viktigare fråga i samhället idag på grund av den negativa påverkan oljud kan ha på vår hälsa. Tunga fordon som driva av förbränningsmotorer står för den största delen av buller i vår omgivning, varför bullerreducering är ett alltmer prioriterat område vid utveckling av dessa motorer och fordon. I denna studie arbetar vi utifrån ett optimeringsproblem för att minimera ljudnivåerna utan att försämra motorns övergripande prestanda. I vår strävan att diversifiera strategier för bullerreducering behövs innovativa sätt att undersöka detta komplexa problem. Här används ett simuleringsverktyg för att undersöka möjligheterna att reducera ljudnivåerna genom att justera komponenternas beskaffenhet. Metoderna för att uppnå detta undersöks och utvärderas också. Resultaten pekar på ett inbyggt optimeringsverktyg i det simuleringsprogram som används hanterar optimeringsproblemet väl, trots dess höga komplexitet. En signifikant bullerreducering uppnås genom justering av inställningar hos två av de komponenter som undersökts. Detta är ett första försök att hantera bullerreducering inom förbränningsmotorer genom simulering av olika komponentinställningar. Med tanke på de lovande resultaten från denna första undersökning förväntas ytterligare förbättringar om simuleringsmodellen kan förfinas och fler komponenter kan undersökas

Utveckling av akustiska simuleringsmetoder för avgassystem

Noise pollution is a growing concern due to its harmfulness to human health. Heavy vehicles powered by internal combustion engines stands for a major part of the environmental noise, why noise reduction is an increasing priority in enginve development. Within this study, an optimization problem is posed in order to minimize acoustic output without impairing the engine's overall performance. In our quest to diversify out noise reduction strategies, innovative ways of investigating this complex subject are essential. Here, we use simulations to investigate the possibility to reduce noise by component settings, as well as methods available to achieve that. Regarding the methods, the results indicates that a built in optimization tool within the simulation software used works well, despite the high complexity of the problem. A significant noise reduction is achieved when adjusting the settings of two of the parameters studied. This is a first attempt to tackle noise reduction in internal combustion engines by component settings. From the promising results, further improvements are expected as the simulation methods are refined and more components can be investigated accurately.Bullerreducering är en allt viktigare fråga i samhället idag på grund av den negativa påverkan oljud kan ha på vår hälsa. Tunga fordon som driva av förbränningsmotorer står för den största delen av buller i vår omgivning, varför bullerreducering är ett alltmer prioriterat område vid utveckling av dessa motorer och fordon. I denna studie arbetar vi utifrån ett optimeringsproblem för att minimera ljudnivåerna utan att försämra motorns övergripande prestanda. I vår strävan att diversifiera strategier för bullerreducering behövs innovativa sätt att undersöka detta komplexa problem. Här används ett simuleringsverktyg för att undersöka möjligheterna att reducera ljudnivåerna genom att justera komponenternas beskaffenhet. Metoderna för att uppnå detta undersöks och utvärderas också. Resultaten pekar på ett inbyggt optimeringsverktyg i det simuleringsprogram som används hanterar optimeringsproblemet väl, trots dess höga komplexitet. En signifikant bullerreducering uppnås genom justering av inställningar hos två av de komponenter som undersökts. Detta är ett första försök att hantera bullerreducering inom förbränningsmotorer genom simulering av olika komponentinställningar. Med tanke på de lovande resultaten från denna första undersökning förväntas ytterligare förbättringar om simuleringsmodellen kan förfinas och fler komponenter kan undersökas

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