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18 Uppsatser om Patch - Sida 1 av 2

Grey-sided vole and bank vole abundance in old-growth forest patches of different size and connectivity

Vole populations in northern Scandinavia vary in cycles with peaks every third or fourth year as described by the National Environmental Monitoring Programme of small mammals (NEMP). Some vole species have declined in population numbers since the NEMP started in 1971, especially the grey-sided vole (Myodes rufocanus) which is nearly extinct in the forested region. Since small mammals are an important food source for several avian and mammalian predators, the decline in vole numbers is expected to have consequences for the whole food chain, especially if other vole species start to decline in numbers. This study tried to test the hypothesis that presence and abundance of M. rufocanus (a specialist species) and Myodes glareolus (a generalist species) can be predicted by Patch size and connectivity of forest Patches >60 years old with a minimum of 15% pine >100years old.

Spawning site selection of brown trout in habitat restored streams

During the timber floating era, most of Sweden?s watercourses were altered. This decreased the amount of available spawning habitats for salmonids, and hence had a negative effect on the riverine brown trout (Salmo trutta) populations. Reconstruction of spawning grounds is today a common measure in restoration of altered streams in Sweden. However, very little evaluation of the effectiveness of these reconstructed spawning grounds exists.

Stålbalkars bärförmåga vid intryckning - orsakad av lokal momentbelastning

This master thesis deals with steel girders subjected to Patch loading caused by concentrated moments. There exist no good methods to calculate by hand the ultimate resistance for this load case. In ?tunnplåtshandboken?, (Handbook for sheet metal, which is published by SSAB), one calculation method is presented. It?s however fairly difficult to use, because of many calculation steps and many graphs.

Effects of brown bear (Ursus arctos) odour on the patch choice and behaviour of different ungulate species

The return of large predators to regions where they were previously extirpated has created a need for knowledge about their effect on prey species, not only their lethal but also their behavioural or risk effects. In this study the behavioural risk effects of brown bear (Ursus arctos) were tested on fallow deer (Dama dama), roe deer (Capreolus capreolus), red deer (Cervus elaphus), moose (Alces alces) and wild boar (Sus scrofa). This was done by using Patches of fur to simulate the presence of the novel predator (brown bear), a novel nonpredator (reindeer (Rangifer tarandus) and no fur as control. These three treatments were then compared. The response variables measured were increased vigilance, decreased feeding time and change in Patch use.

Vems landskap ska förändras för att öka den biologiska mångfalden? : En studie av skillnaderna i odlingslandskapets konnektivitet med avseende på två skyddsvärda arter med olika preferenser

Organisms relevant for nature conservation dont follow administrative borders. Because of this there is a need for a landscape perspective within conservation and planning, and a need for the species of interest to have legal protection. Network analysis adapted for ecological purposes has grown to become a powerful tool for studying and communicating the relationships between species dispersion and access to habitat. In this study the following question is posed: How is the Osmoderma eremita and the Pernis apivorus dispersal possibilities in the small scale cultivated landscape of Borås affected by exploitation in respect to a) dispersal ability, b) habitat quality, c) position of habitat Patches in a network? The analysis were based on municipal and regional nature conservation data, which in due to confidentiality is not accounted for in the report by maps, coordinates, etc.

Site preparation, planting position and planting stock effects on long-term survival, growth and stem form properties of Pinus contorta on southern Iceland

In order to evaluate different afforestation methods for exposed heath lands a field experiment was established in Mosfell on southern Iceland in 1989. The trial comprised six different site preparation methods (control, herbicide application, tree shelters, Patch scarification, TTS trenching and mounding). In total 960 container seedlings (1+0) and 960 Nisula roll transplants (2+1) of lodgepole pine were planted. Various planting positions (furrow, hinge, no site preparation (control) and on top of mounds) were tested within the site preparation treatments. This study involves renewed measurements and analyses of the trial.After 19 years the overall survival was 51,7 %.

Effektiv uppdatering av datorspel med hjälp av filskillnader

Detta examensarbete undersöker om och hur man med hjälp av filskillnader kan effektivisera uppdateringar av datorspel. Flertalet olika tester med deltaenkodning har utförts, detta på olika versioner av filer från kommersiella och aktuella spel. Bland annat har försöken med deltaenkodning jämförts med de officiella speluppdateringarna, och med vanlig komprimering av de aktuella filerna. Resultaten visar att användning av deltaenkodning på de filer som ändrats mellan spelens versioner kan vara mycket effektivare och ta mindre plats än de officiella speluppdateringarna..

Interactions between some plant-parasitic nematodes and Rhizoctonia solani in potato fields

The pathogenic fungus Rhizoctonia solani causes major economic losses for potato producers in Sweden. The producers, as well as advisors, have reported possible increases in severity of R. solani when free-living plant parasitic nematodes are present and active. There are several examples in the literature of interactions between pathogens where one, or both species, support or increase the damage made by the other organism. These complexes are important to investigate and to be able to forecast, since even low incidences of fungi or nematodes may result in an interaction of significance.

En studie av landskapsindex för kvantifiering av rumsliga landskapsmönster

Syftet med uppsatsen är att utvärdera två landskapsindex: ett formindex som beräknar formen för varje markanvändningsyta ( eng. "Patch"); ett diversitetsindex, som beskriver de olika markanvändningarnas relativa utbredning. Formindexet beräknas på två olika sätt, beroende på om dess storleksberoende inkluderas eller ej. Utvärderingen körs för ett landskap på cirka 50 km2, men även för tre mindre områden i landskapet: åkerbygd, mellanbygd samt skogs-bygd. Samtliga områden jämförs sedan i två olika skalor, flygbild respektive satellitbild..

Utvärdering av metoder och modeller för att simulera växlingskomfort i entreprenadfordon

Good comfort for the driver of a construction machine is crucial. Gearshift comfort is an important part of the total comfort. Volvo Construction Equipment Components has a simulation environment of the powertrain, SimPow, which is implemented in Matlab/Simulink. SimPow is mostly used for simulation of control strategies and performance. In order to be able to study gearshifting comfort, Volvo has an interest in developing new models for SimPow.

Kvalitetsregister för epikutantestning

Inledning: Epikutantester används för utredning av kontaktallergier. Det görs ca 3000 tester varje år i Sverige som överförs till ett kvalitetsregister.  Målet med projektet var att utveckla en webbapplikation och en underliggande databas för hantering och lagring av ett nationellt kvalitetsregister för epikutantester (The Swedish Patch Register). Databasen skall lagras på en central server lokaliserad på Universitetssjukhuset, Örebro.Metoder: Lösningen blev en applikation för webbläsare programmerad i språket C# med hjälp av Microsoft Visual Studio 2008 och ramverket ASP.NET 3.5. MySQL .NET connector tool 6.2.2 möjliggjorde anslutningen mellan ASP.NET och databasen.

Fosforgödslingseffektivitet i långliggande bördighetsförsök

Rapid population growth and the fact that phosphorous is a limited resource implies that the question regarding an efficient use of phosphorus is of great importance, and consequently,that the phosphorous use efficiency should be as high as possible. The view on phosphorous use efficiency, and how this is calculated, has varied over time. This has had great implications on what type of research that has been conducted, which have resulted in an inconsistency between the academic?s view on the subject and recommendations received by farmers. The purpose of this paper is to calculate the phosphorus use efficiency in the Swedish long term fertility experiments.

Vidhäftning mellan prefabelement och pågjutningsbetong : Undersökning hur skrovligheten påverkar vidhäftningskapaciteten vid skjuvning

Self-compacting concrete has soon been around for a decade. Recently the prefabrication industry has started to use this fairly new concrete type in larger scales, mainly because of its distinctive properties.  There are still certain areas that need to be thoroughly examined, such as bond capacity. There have been very few studies regarding shear capacity due to the fact that the procedure is complicated.This report will highlight a method to examine the shear capacity of different surfaces that have been prewetted as well as non-prewetted surfaces. The surface areas follow BBK 04?s and Eurocode 2?s demand for surface roughness.  A smooth surface will be completed in order to confirm if the different shapes influence the bond strength by shear stress or not.                       The purpose of this essay is to measure the bond strength within the shear capacity as well as examine the impact it has on surface roughness and treatment for shear bond.The method used to identify the shear capacity is called L-shaped Push-Off Test.

Plantetablering och tillväxt för sådd och planterad tall 2-5 år efter markberedning med harv eller Huminmix-teknik inom Holmen Skog distrikt Norsjö :

The objective of this work was to compare the environmentally gentle soil scarification technique Huminmix (with possibilities to do track-grinding/HMMspår, long-scraping/HMMlångfläck and mounding/HMMhög) with conventional disc trencher, concerning seedling establishment and growth of direct seeded and planted Scots pine seedlings. Inventories were made during June and July 2005, in 34 seeded and 6 planted stands from 2000 ? 2004 (1- 5 years old) of lichen- and myrtillus/vaccinum-type in Holmen Skog AB´s district Norsjö in Västerbotten. The Huminmix-technique had been used for HMMspår in the seeded stands and for HMMhög in the planted stands (HMMlångfläck has been used from the year 2006 for direct seeding). The studied stands had been seeded with the same amount of seeds according to stand data.

Två linsrengöringsmetoders påverkan på hornhinnan i samband med användande av kontaktlinsvätskan Opti-Free® Express®

Syfte: Studiens syfte var att jämföra två linsrengöringsmetoders påverkan på hornhinnan. Studien jämförde tillverkarens rekommenderade användningsinstruktioner för Opti-Free® Express®, med den alternativa rengöringsmetoden att gnugga linserna, något som ofta rekommenderas av optiker.Metod: Deltagarna sågs vid två tillfällen för utvärdering av eventuell påverkan på hornhinnan. Värdena som återfanns vid första tillfället fungerade som ett utgångsvärde. Samtliga fynd dokumenterades, graderades och poängräknades efter vilken typ av staining samt utbredning. Cornea delades in i fem regioner; centralt, superiort, inferiort, nasalt och temporalt.

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