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40 Uppsatser om Quantum detector - Sida 3 av 3

Närvarodetektor med IR och ultraljud

En närvarodetektor i form av en IR-detektor uppfyllde inte de önskade kraven och Eluw Electronic AB hade planer på att utveckla produkten vidare. IR-detektorn registrerar endast rörelse på en person vilket inte alltid är tillräckligt i företagets anläggningar. En person som inte är i rörelse måste också detekteras för att upprätthålla säkerheten runt en specifik anläggning. Företaget efterfrågade en närvarodetektor som klarade båda dessa detekteringar. Ett examensarbete på Luleå tekniska universitet löste uppgiften och en väl fungerande närvarodetektor med IR och ultraljud har utvecklats.

Tillståndskontroll av hydraulmotorer med hjälp av magnetindikator

Detta examensarbete är utfört vid Luleå Tekniska Universitet på uppdrag åt Hägglunds Drives AB i Mellansel. Hägglunds Drives tillverkar kompletta hydrauliska drivsystem, som inkluderar hydraulmotorer. I en hydraulmotor uppstår det slitage när metalliska ytor kommer i kontakt med varandra när till exempel ett lager får otillräcklig smörjning. Slitaget ger upphov till metalliska partiklar som cirkulerar i hydrauloljan och samlas upp i ett filter. Genom att samla upp och studera slitagepartiklarna kan man uttala sig om hydraulmotorns kondition.

Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier

Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in the event of rainfall. An increased level of radioactivity in the plants may occur due to interception and retention of the radionuclides. If the content of the plants is above the threshold limit value, entire yields may have to be destroyed. In order to prevent contamination or decrease the content countermeasures can be taken. The impact of the biomass, leaf area index (LAI) and growth stage of the plant on the interception and retention is important to know in order to decide which countermeasures to use. Weather may also be an important factor. In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley and spring oil-seed rape was studied.

Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier

Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in theevent of rainfall. An increased level of radioactivity in the plants may occur due tointerception and retention of the radionuclides. If the content of the plants is above thethreshold limit value, entire yields may have to be destroyed. In order to preventcontamination or decrease the content countermeasures can be taken. The impact of thebiomass, leaf area index (LAI) and growth stage of the plant on the interception andretention is important to know in order to decide which countermeasures to use.Weather may also be an important factor.In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley andspring oil-seed rape was studied.

Värdeflödesanalys på Saab Training Systems i Huskvarna

Saab Training Systems (STS) in Huskvarna is manufacturing material for educationalpurposes to armies worldwide. They are now implementing parts of the Lean productionconcept in their organisation.One part of the work with Lean production is to eliminate waste. To be able to identify waste,value stream mapping is a good tool and also what we used in our thesis. To gain a betterefficiency in the production of Personnel Detector Device (PDD) flow was one of our goals.The PDD is a harness used during battle training which registers if the user is being hit by itsenemy.Our work with the thesis started up with a short education in Lean production and in valuestream mapping (VSM). The work proceeded with a VSM of the production flow of the PDD,interviews were made and studies of literature were done to gain greater knowledge of thesubject and solve the task.The VSM resulted in five areas which were followed up out of those six we identified.

Implementering av Constant Fraction Detection vid avståndsmätning

This thesis is performed at Saab Bofors Dynamics in Karlskoga and investigates a technique for ranging with laser pulses. The investigated technique is called Constant Fraction Detection (CFD). Described briefly, the received laser pulse is split into two equal parts, where one part is delayed half the pulse width and inverted. This signal is added to the original pulse. The resulting curve has the shape of a laying S and the detection of the zero level is used to stop the time measurement.

Rotningsstimulerande effekt och kemisk analys av vattenbaserad extraktion av vedartade och örtartade skott av Salix smithiana Willd. :

Cuttings of Lonicera xylosteum L. were treated with willow extract to study the response in rooting capacity. The extracts were prepared by mixing chopped pieces of Salix x smithiana Willd. with water in a warring blender. The investigation comprised 2 types of salix extracts based on differences and dynamics between twigs in winter dormancy and twigs with new shoots. To explore the rooting response, three tests were made.

Uptake of 137Cs by fungi and plants due to potassiumfertilization in Heby municipality in response to theChernobyl nuclear accident

The fallout from the Chernobyl nuclear accident resulted in large deposits of caesium, iodineand strontium as well as noble gases in various parts of Sweden. 137Cs has a radioactive halflifeof about 30 years and is therefore one of few radio-fission products remaining inmeasurable quantities in the Swedish soil. Radiocaesium behaves similarly to potassium insoil-plant systems and is easily absorbed by plants. It is important to understand how 137Csbehaves in different ecosystems in order to minimize the risk toward humans.The aim of this study was to determine how potassium fertilization influences radiocaesiumcontent in different forest plants and fungi. Potassium fertilizer was spread once in 1992 withapproximately 200 kg KCl per ha.

Metodutveckling för analys av PBDE och HBCD i sediment

Brominated flame retardants (BFRs) has for many years been used in products to reduce their flammability, mainly in electronic products, textiles and construction materials. In 2003, Sweden imported 300 tons of brominated flame retardants. Leakage of these compounds has polluted natural environments. Fishes has shown increased contents of these substances, especially fat fish, since brominated flame retardants tends to accumulate in fatty tissues. They are also regarded as persistent and that gives them the ability to travel long distances. What also is really scary is that increased levels of brominated flame retardants have been detected in human breast milk. The knowledge of the brominated flame retardants is limited and not so much research has been done in this field. There are many reasons though, to keep the research going. Partly their structural resemblance to well-known toxics as PCB, but also their ability to accumulate in biological systems and enrich in food chains. In which way they affect humans we really don?t know yet.

Potentiell fosforfrigörelse från sedimentet i Bornsjön, sydvästra Stockholm : The potential leakage of phosphorus from sediment in Lake Bornsjön, south western Stockholm

Lake Bornsjön is situated 30 km southwest of Stockholm in a rift valley lake and consist three basins outstretched in northwest-southeast direction. The surface area is 6,7 km2 with a maximum depth of 18,3 meters, a mean depth of 9,8 meters and a retention time of the water of 6,5 years. The drainage area is 42 km2 and consists mainly of arable land (ca 1000 ha) and productive forestry land (2500 ha), but in the drainage area there are also restored and fairly newly constructed wetlands.Today the Stockholm area receives its drinking water from Lake Mälaren, but if there would be any pollution of this source, Lake Bornsjön would act as the water source. The area surrounding the lake was bought already in 1899 by Stockholm Stad for protection of the lake and was taken over 1993 by Stockholm Vatten AB. It has been a water protection area from 1988 and it was also accepted as a nature reserve in 1995.

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