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599 Uppsatser om Manually killed trees - Sida 36 av 40
Kan man genom kartstudier förutse häckningsframgång för ängshök (Circus pygargus) i Uppland? :
Montagu´s harrier (Circus pygargus) is a diurnal, Eurasian raptor, which migrates from its northern breeding grounds to winter in sub-Saharan Africa. In Sweden, its core breeding area is centred on the island of Öland, with a stable breeding population of approximately 40 pairs. The province of Uppland is on the northern end the distribution range, where 4-8 pairs have regularly bred since the 1980s.
In Sweden, the Montagu?s harrier is classified as an endangered (EN) species. This classification is partly due to a lack of preferred nesting habitat, such as shrub-lands or dense wetlands with Claudium spp.
Gångvägsljus :
Discussing light and lighting in the night-time environment of Tensta, a Stockholm suburb built between 1962 and 1970, this thesis suggests that lighting should be designed for the outdoor environment as a whole. The feeling of safety and human perception are important components in this thesis.
Starting with some comments on visual perception and how we adapt our sight to an interval of the visual input we get, makes it possible to understand that more light sometimes hides, rather than reveals, things. Amongst the dispersed houses, in the green parks of Tensta, this turns the pedestrian roads, lit by pole-top-mounted fixtures, into light tunnels in a dark surrounding.
Talking about the feeling of safety I am inspired by, amongst others K. Lynch, B. Hjort and J.
Utveckling av en dynamisk Simuleringsmodell av en skotare
The predominant forestry harvesting method is based on the harvester-forwarder method, theharvester folds, branches and cuts trees, and sorts the logs into piles, while a forwarder transportsthe logs to a landing area.This master thesis work is about realization of a dynamic forwarder simulation model, and itspurpose is to provide an integrated forwarder simulation model in MATLAB/SimMechanicswhere the forwarder is based on a concept using pendulum arms to connect wheels and chassis.Active suspension control is developed and implemented into the simulation model, and finallycompared in simulation with passive suspension.In a first step, an integrated forwarder simulation model is developed, containing a simplifiedforwarder model, a tire-to-ground interaction model and a test track model. The simplifiedforwarder model is based a rigid multi-body system with a spring-damper suspension of thependulum arms. The tire-to-ground interaction model calculates the reaction forces, friction fromthe ground and applies the propulsion force. The test track model is a simplified version of thereal test track in Skogforsk. The propulsion wheel torque control is used to regulate theforwarder speed.
Mänsklig påverkan på mindre vattendrag i skogslandskapet : en inventering av vägtrummor och skyddszoner kring dessa i Uppsala län och norra Västmanlands län
Interference in an ecosystem means a disturbance. When harvesting, forest roads have to be
build to cope with heavy duty vehicles. Crossing brooks can not always be avoided. In this
case bridges or culverts have to be built. There are many different kinds of culverts and
depending on what type you choose and how you place the culvert, the watercourse and the
water organisms can be harmed in different ways.
Timmersorteringens inverkan på sågverksekonomin :
Modern sawmills are using the raw-material and the production-capacity more efficiently
today, due to rising raw-material prices and higher production costs. Log sweepness has a
negative effect on the sawn yield, for sawmills with straight-sawing. It is desirable that these logs could be sorted based on more criteria, if it increases value-yield and consequently the utilization of raw-material.
Bow-heights over 1 cm have a negative effect on sawn yield, since the surface of the
mantle cuts down in the sawn pattern. Some of these small bow-heights reduce the logs yield of value which affects the production planning negatively. Nearly half of all the Swedish logs have a bow-height over 1 cm.
Mekanisk integration av en IR-detektor i en Stirlingkylare
The master thesis ?Mechanical Integration of an IR-detector in a Micro Cooler? has beenperformed at FLIR Systems AB in Danderyd. FLIR Systems is a world leader in the design,manufacture and marketing of thermal imaging camera systems.The thesis project is divided into to two areas, Production Method and Noise.The Production Method concerns the positioning of a detector on the cold finger within the IRcamera.The detector has to be positiond with very high accuracy at the center of the cold finger,so it can be placed in line with the optical axis to avoid movement of the picture during zooming.The positioning of the detector is at present done with the help of specially designed guides on aplate on top of the cold finger. The design workes well but the special machining needed for thisplate is very expensive.The goal concerning the production method was to derive a new more cost effective method forthe assembling and positioning of the detector on the cold finger by replacing the guides on theplate with a reusable equipment or some other alignement operation.Several concept ideas have been generated with the help of concept generation methods in theform of concept classification trees and concept combinational tables. Two of these conceptswere selected to be further refined.
Precommercial thinning stumps´susceptibility to Heterobasidion spp : a comparison between high and low Norway spruce and birch stumps : a measuring of the efficacy of Phlebiopsis gigantea stump treatment
Each year, Heterobasidion spp. is a major cause of economic losses to forestry in the northernhemisphere, including Sweden. New results indicate that pre?commercial thinnings could be at riskfor Heterobasidion spp. infections.
Analys av individinriktad ekskogsskötsel i Blekinge : en metod för tillämpning i ett kontinuitetsskogsbruk?
Ett ökat brukande av skog enligt skötselprinciper som leder till skiktade beståndsstrukturer, en blandad trädslagssammansättning och kontinuerligt skogbeklädd mark har potential att öka den biologiska mångfalden och värdet för rekreation (Emborg m.fl. 2000, Berg m.fl. 1995, Mattsson & Li 1994, Holgen m.fl. 2000). I ljuset av detta, tillsammans med svårigheterna som finns att nå goda ekonomiska resultat vid skötsel av ädellövskog (Lindén & Ekö 2002), ses det idag som angeläget att uppmärksamma och studera alternativa skogsskötselmetoder (Cedergren 2008) .
I östra Blekinge har ett antal skogsägare under längre tid praktiserat en metod att sköta naturligt föryngrad ek i blandbestånd som går ut på att, mer eller mindre tidigt, frihugga ekhuvudstammar, och att dana kvalitet genom stamkvistning/beskärning.
Design och implementering av ett webbaserat personalhanteringssystem
Quickmatch is a company that recruits students to other companies that need temporary workers. Today all administration is done by hand, which is very time demanding and therefore inefficient. Employees send assignment reports by e-mail about the working hours and breaks to the administration office. Since these reports are handled manually, there is a great need for an automated system that makes the company more scalable.The purpose of this work was to solve the defined problem, i. e.
Implementering av lean i ett gjuteri med låga volymer och hög variation
Valmets own foundry in Karlstad has during a long period of time had problems being profitable. The goal today is to turn this around. Today there are three different productionlines; engine blocks, Yankeecylinders and components for the wind turbine industry. This master thesis has focused on examining if value stream mapping is a useful tool to use in a foundry, and therefore outside the typical manufacturing industry. The target has also been to evaluate if there is a possibility to improve the flow in the foundry and also the results.During the 20 weeks this work has been done at the foundry data has been collected and analyzed.
Gallringsinventering från helikopter utrustad med profilerande laser och kamera för låghöjdsfotografering
Today Holmen Skog finds and selects suitable thinning stands using data on upper height and basal area. These figures are often based on basic forest data that has been updated with the help of growth prediction models. The problem is that these figures are not always correct. The aim of this study was to investigate if a combination of data from a profiling laser and a digital camera for low elevation photography, can be used for collecting data on number of stems per ha, tree species mixture as well as basal area weighted mean height and upper height for stands. The possibility to use these data to assess the need for thinning cutting was also investigated.Laser data and aerial photographs were collected from a helicopter operating at an approximate height of 100 meters.
Träd och buskar i kantzoner : en undersökning av kanteffekter i några av östersjöregionens skogar
Around the world, forests are generally being fragmented and as plant populations decline in both sizeand number of individuals, the genetic variation will also decrease whitch in the end leads to totalextinction of the plant. In this paper, I wanted to investigate what specific species of trees and shrubsyou usually find in the edge and core habitats in some of the forests in the Baltic Sea region. I alsowanted to identify the edge effects and their sources and finally compare the results between thedifferent regions.The data sources used are derived from the ongoining research project Landscape structures, patterns ofbiodiversity and conservation strategies in the Baltic Sea region by Kari Lehtilä, Patrik Dinnétz ochTiina Vinter who have made a record of all herbaceous plant species in four randomly chosen forestregions situated around the Baltic Sea: Estonia, Skåne, Södermanland and Germany. I made statisticalanalyses, using the computer program R, concerning the distribution of species in the edge habitats ofthe forests as well as in the core habitats. I performed generalized linear models and then variationanalyses with the factors light and biomass in order to investigate wether edge effects might appear dueto these factors.
S:t Sigfrids granne : en begravningsplats för alla
This paper is about cemetaries in a multireligious society. The aim of the work is to compare the physical expressions of different religions burial traditions, in order to plan a multireligious cemetary in Borås.
I´ve studied the five worldreligions, Judaism, Chritstianity, Islam, Buddhism and Hinduism. I´ve also written about the Humanism, a nonreligious organization, and funerals without any religious connection.
Litterature studies gave basic knowledge about the religions beliefs, and interviews with a person from each group deepend the knowledge, mainly regarding the burial traditions.
Aktivitet som sjukdomsmarkör på kalvar i gruppsystem :
Since long, Sweden has had exceptionally low calf mortality compared to most
other countries. The tradition has been to keep calves in individual pens. With
increasing number of cows per herd there is now a larger interest in more efficient
and economical group systems for housing calves. However it has been noticed
that bigger herds have more health problems and higher calf mortality than
smaller herds. The early signs of disease are harder to detect when the animals are
not fed manually.
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.