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2258 Uppsatser om Damage investigation - Sida 2 av 151

Vindskador vid stickväg i 1:a och 2:a gallring i Boxholm, Östergötland : i stormen Pers fotspår

Wind damages next to strip roads in 1st and 2nd thinning in Boxholm, Östergötland Anneli Fransson, SLU, inst f sydsvensk skogsvetenskap, Examensarbete no 108 Wind damage is something we are all familiar with since the storms Gudrun (2005) and Per (2007). Research about strip roads and wind damage is very limited. It is commonly known that the trees next to the strip roads more often fall whit heavy winds, and the purpose of this thesis was to verify this statement. Data was collected from first- and second thinnings at Boxholms Skogar AB, Östergötland. In first thinnings data was collected from both spruce and pine stands and second thinnings only data from spruce stands was collected.

Vildsvinsskador inom jordbruket : hur stora är förlusterna?

Problems with wild boars are increasing in Sweden and some people argue that the wild boar population must decrease. This is mostly the opinion by farmers, while the hunters want more wild boars in Sweden. Today the population is the strongest in the south of Sweden and in the eastern parts of the country. However the population is growing stronger in other parts of Sweden as well. The population origins from these areas where they escaped from pens around 1970.

Tallens fortsatta tillväxt i älgbetade bestånd

The Swedish Forestry Research Institute implemented an experiment which began in the year 1979 in a by moose browse damaged area in Sweden. An audit in 2014 of the moose browsing study called ?Furudalsförsöket? is the underlay to the study's results. By comparing Scots pine stands development in relation to known damage obtained thereby gives the understanding of how browsing affects the short and long terms impacts of Scots pines quality and volume production. The results of this year's audit reveal that the standing volumes in the undamaged and damaged areas represent a significant difference. The number and volume of the ingrown trees constitute a larger proportion of the areas that have been heavily browsed. It also proves once again that that all damage classes had a downward trend, which means that the damage is concealed with time.

Vindfällning i naturliga och skapade bryn och kanter :

The aim of this work was to study if the edge of the forest is more resistant to heavy winds than the trees located further in from the edge, and how this edge effect changes between different types of tree species and site types. The data was collected from an electric power line going from the north to the south of Sweden. The mean value of the clearcutted area around the power line was 120 meters. The main direction of the storm in January 2005 was west-southwest and thus the power line was a perfect place for gathering a large data set. The main parameter studied was the damage frequency at the edge of the forest compared to the trees located further in from the edge (up to 100 m from the power line). Tree species mixture, soil moisture class, soil type, topography, stand height, stand height of the stand on the other side of the power line and wind exposition was estimated. The results showed a distinct edge effect. The edge of the forest had clearly lower damage frequency for all tree species. A marked difference was observed between tree species and damage frequency.

Skötsel av älgskadade bestånd :

Sweden has today the highest moose (Alces alces) population in the world. The population has been very high since the late seventies and in the beginning of the eighties there was a big ?moose explosion?. The main food source for moose during the winter is young pine (Pinus sylvestris) and birch (Betula spp.). The high moose population has therefore lead to high damage on pine forests over big areas.

MCNP-modell för beräkning av neutrondos och DPA på reaktortanken vid Ringhals 2

In this report an MCNP (Monte Carlo N-Particle) model is described for the reactor vessel at Ringhals 2. The model is validated against the specific activity in neutron dosimeters, extracted in 1977, 1984 and 1994. The validation showed that the calculations of the model are within the requirements of a maximum of 20 percent uncertainty for every neutron dosimeter except one, extracted after the first cycle. The uncertainty of this cycle was mostly due to the operation data rather than to the MCNP model.The model has been used to investigate various questions concerning radiation damage. The reliability of the traditional measure of radiation damage, fast neutron flux (En > 1MeV) has been evaluated.  This has been done by taking the ratio for this and another measure of radiation damage, DPA (Displacement Per Atom), for various positions and layers.

Nyckeltal för älg och fodertillgång på tall Pinus sylvestris och rönn Sorbus aucuparia

It has been shown that moose can affect plant community composition and structure. Selective browsing with other damages of large herbivores on tree species with different tolerance to disturbance could reshape the tree layer in both managed and natural forests. Rowan Sorbus aucuparia is widely distributed throughout Sweden and Europe. Research has shown that browsing by moose may prevent rowan from reaching browsing safe heights. The goal has been formulated that, where rowan is indigenous, it should have a good competition status and be able to reach tree level.

Stamskador i gallringsbestånd

This study was conducted on a property with a thinning machine team. The purpose was to investigate in which machine, the harvester or the forwarder, that caused most damage to the trees in six different stands. Different factors, related to the damage frequency in the stands, were checked out. For example: basal area per hectare, thinning strength, tree diameter and the rate of production. The harvester drivers were also interviewed about how, when and why stem damages occur and how to minimize them. The study stated that 4.3 percent of the trees were damaged. Out of these 88 percent was caused by the harvester and the rest, 12 percent, by the forwarder..

UCAV- Rättfärdighet och ansvarsutkrävande i obemannade luftanfall

Obemannade flygplan med attackförmåga (UCAV) används i allt större utsträckning i konflikter idag. En av de främsta fördelarna med dessa är att det inte finns någon risk att mista en pilot, då dessa är fjärstyrda. I attacker utförda av amerikanska UCAV:er i framför allt Afghanistan och Pakistan, har collateral damage inträffat vid ett flertal tillfällen. Det innebär att civila oavsiktligt fallit offer för attacker. Enligt krigets lagar kan sådana händelser rättfärdigas av att militär nödvändighet föreligger, men det är tveksamt om det går att hävda det när man inte riskerar egna förluster.

Utvärdering av en ny typ av lagerinbyggnad för traktionsmotorer

The thesis evaluates a new kind of bearing arrangement in a traction motor that ABB hasdeveloped. Since the arrangement is designed in a new and innovative way it needs to beevaluated to see if it is safe to use. In today?s traction motors, bearings with a big internalclearance (C4-clearance) are used. The basic idea of the new arrangement is to reduce the fitsbetween the bearing and shaft/house.

Vivlar på prydnadsbuskar - nya arter eller förändringar i födopreferenser?

During the last couple of years leaf-edge-cuts, typical to Otiorhynchus wingless-weevils, have been discovered on ornamental shrubs, especially Syringa vulgaris lilac and Ligustrum vulgare privet. These plant species have not earlier been attacked by wingless-weevils and because of that, the aim of this study is to see if new species of weevils have been established in Sweden or if the domestic weevils have changed their food preferences. This work also includes a literature study of known weevil species in Sweden and their host plants, and of wingless-weevil species in Europe that could be invasive here. Locations, where damage to previously named plants has been reported, have been examined. The extension and appearances of the damages have been documented in order to study if different weevil species make different types of edge-cuts.

Skottbetning på granplantor i Kolmården : omfattning och påverkande faktorer

In the Kolmården area, northeast of Norrköping in south-central Sweden, it was discovered that shoots of spruce Picea abies, plants to a seemingly large extent had been browsed by deer. The area inhabits a dense red deer population, alongside with moose and roe deer, and red deer is thus suspected to cause the damage. The main purposes of this study are, however, to estimate the extent of the shoot-damage and to investigate what factors that may affect the browsing of shoots. For each stand information was recorded about the age of the plants, area for the stand, height over the sea for the stand, site productivity, type of plants and stand-history. The study was done in three areas: Simonstorp, Stavsjö and Valinge. At Simonstorp and Stavsjö, respectively, 10 stands were chosen for study and on Valinge six stands. In each stand, 10 plots were sampled.

Torvmarkernas utveckling i östra Uppland

This report is about a couple of specially chosen peatlands in eastern Uppland, Sweden. It concerns their development between the year 1922 and 2012. The historic fact originates from a large investigation of peatlands in the south of Sweden made by the Swedish Geological Survey, SGU, in the 1920?s. To be able to choose peatlands an analysis in GIS were made, in which we were able to find locations good enough for our field investigation. During the field investigation we bore to find nice peat cores that later went through several analyses in a lab.

Hägn i skogsbruket :

This survey was made during the autumn of 2002 and the beginning of 2003, on commission from the National Board of Forestry. The purpose with the survey was to gather experience and knowledge in the organisation about fencing and this was made through interviews. The ambition was also to get knowledge from people outside the organisation that have great experience of forestry and fencing. The interviews were based on questions that have been composed by the author with help from the supervisors. The questions were the same to both the personal from the National Board of Forestry and to the foresters. Interviews were also made with private landowners, gamekeepers, game researcher, the County Administrative Board, the National Road Administration, pole and net retailers and contractors. The target group for this work is the National Board of Forestry to be forwarded to persons interested in forestry with the ambition to spread knowledge about how to prevent damage on the forest by browsing animals. The deer populations are big in the south of Sweden and growing populations have increased the damage on plantations of broadleaves of the most species.

Behandling av tinnitus med kognitiv beteendeterapi ? en litteraturstudie

Tinnitus is the perception of sound in the absence of an external source. 10-15 % of the population is experiencing tinnitus. There are different causes such as damage to the inner ear, musculartension and stress. Tinnitus affects many different aspects of an individuals life and often disturbs everyday activities. There are different treatments for tinnitus.

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