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544 Uppsatser om Wood boring insects - Sida 9 av 37

Skogsentreprenad idag och i framtiden : en kvalitativ studie av skogsmaskinentreprenörersverksamhet och framtidsvisioner

The Department of Forest Products and Management, Swedish University of Agricultural Sciences has received means from Vinnova for a preliminary study of the organisation of logging work of today and how a better logging organisation should be brought about. This thesis reports results from qualitative interviews with nine forest machine contractors regarding the situation of their companies. The interviews have been analysed with respect to the genesis of the companies, which tasks they perform or that they could consider perform-ing, business relationships of the companies, relationships between the different partners of the companies, and the state of competition experienced by the contractors. The companies have developed either from the contractor previously being machine operator employee or from that the contractor in making has owned a machine and needed work. Their primary business is mechanised logging.

Val av stommaterial : Vilket är det mest fördelaktiga stommaterialet vid uppförande av en hallbyggnad?

When constructing an industrial- or hall building, the most common framework materials thatis used are wood, steel or concrete. Due to an assignment from Byggnadstekniska Byrån ABhas a document been created that makes it possible to investigate how the final costs is af-fected by gapes in between elements and which used foundation. And this with steel as thematerial. The purpose with this essay is to investigate which is the most well fitted materialwhen constructing an industrial- or hall building wood, steel or concrete. Information aboutthe different materials has been collected by litterateurs and by different internet pages.

Förutsättningar för återintroduktion av stora gräsätare i Sverige

Biodiversity is under threat in Sweden and many species are on the brink of extinction. This is mainly due to the large-scale drainage projects during the 19th and 20th century and the increasingly intensive land use in agriculture and forestry. The intensive land use with sharply defined boundaries between the production units has in many cases led to either overgrazing or overgrowing. As a result many species have been pushed back to "leftover" habitats like shooting ranges, power line corridors, roadsides, dumps, embankments and other similar areas. Therefore the question has been raised, wether or not it is needed to re-introduce large herbivores into the wild in order to maintain the biodiversity that is related to the extensive land use.This study has been conducted as a literature review and will focus on the European bison?s (Bison bonasus) impact on other species and biodiversity; conditions for reintroducing large herbivores in Sweden are also discussed.Free roaming populations of large herbivores have a positive impact on plants, insects and many other groups of organisms.

Varför klarar inte vissa elever som fått godkänt i grundskolan av gymnasiets Matematik A?

The purpose of this essay was to understand why the pupils of upper secondary school are unable to pass the Mathematics A level. As method, I chose interviews, since the personal and various experiences of the informants are very important for the validity of this essay.This study has shown that the students lack motivation and consider Matematics boring. They haven?t been able to fathom the connection between the subject and how it van be used in everyday life. If the pupils? are to pass their Mathematics A level, they need time, further recourses and teachers who are apt and attentive pedagogues.Additionally, the teachers need more knowledge when it comes to methodology and didactic styles..

Föroreningar orsakade av stenar inblandade i barrmassaved

Holmen Skog AB is an important supplier of conifer pulpwood to the Iggesund Paperboard mill. After logging and transport to the landing by a forwarder, the wood is loaded on trucks for further transport, often by using separate loaders. During this handling process considerable amounts of stone material is sometimes mixed into the pulpwood and this causes problems for the industry. The aim of this study is to identify which part of the chain from forest to pulpmill, that contributes the most to this contamination. Sizes and total volumes of the contaminating stones were also investigated.

Hallsta Pappersbruks virkesförsörjning

Competition of spruce fiber raw materials has increased dramatically in the last few years, leading to the fact that transportation costs in the current situation represents a much larger share of the total raw material cost. The Holmen-owned pulp industry Hallsta Paper Mill's location on the coast also constitutes a problem, because of the lack of raw material, which is much larger there, than for a pulp mill located in the hinterland. For a coastal industry it?s therefore natural to import much of the raw material by boat or to buy it from the timber terminals, in order to maintain good profitability. The purpose of this study was to analyze how the size of Hallsta Paper Mill timber supply area, without competition, with competition and with terminal use, affects the company ?s transport costs.

Utvärdering av tillverkningsmetoder för svarvbommar

On today?s competitive market, it is difficult to achieve profitability trough high prices on manufactured products. Profitability must be obtained through low manufacturing costs, high quality and short lead times. One of the companies on the market is Sandvik Coromant, manufacturer of tools and chips for metal cutting. This master thesis investigates the methods of manufacturing for boring bars at the manufacturing unit GVH4 at Sandvik Coromant in Gimo, Sweden.

Konstruktion av serviceutrustning till tunnelborrningsmaskin

The Master Thesis work this report is based upon has been conducted in cooperation with Svea Teknik AB. Svea Teknik is a consultant firm which is developing parts of a tunnel boring machine on behalf of Atlas Copco. The machine is being developed to mechanically excavate hard rock by fixating itself in the tunnel and then press a large rotating cutter-wheel equipped with disc-cutters against the tunnel wall. The disc-cutters are the tools that are in direct contact with the hard rock and are therefore exposed to extensive wear and needs to be replaced on a regular basis.The purpose of this Master Thesis has been to develop a service equipment that will enable time effective and safe changes of disc-cutters. The disc-cutters have a diameter of 17 inches and weigh about 130 kg.

De finns ju vissa bra grejer och vissa lite dåligare, tråkigare grejer med läxor : Elevers erfarenhet av läxor på lågstadiet.

The purpose of this study is to examine how some early year pupils define homework, how much homework they get and also how these pupils perceive that they are affected by the homework. The study is qualitative where ten pupils participated in a semi structured interview. The study will show that these pupils are given homework once a week. The homework is mostly math and reading. The study will continue to show that the pupils believe that homework is important for their learning and also that homework often is boring and that it competes with recreational activities such as friends, sports and rest.

Deadwood in piles or distributed : does it make any difference to saproxylic beetles?

Piles of deadwood are often retained in forests after management to support the biodiversity ofsaproxylic organisms which depend on deadwood to survive. Any knowledge about the crucial role ofpiles as suitable habitat of saproxylic organisms compared to single distributed deadwood objects thatare around the piles would help conservation actors to motivate more forest owners to supportsaproxylic organisms during their management. Therefore to give facts to this the saproxylic fauna ofdifferent pile positions (up and low) was studied and compared to distributed deadwood samplesaround each pile. Our study was focused on saproxylic beetles. Some other parameters such asdiameter, deadwood volume, pile volume and decay stage were assessed to define any effect.

Uppvärmning av mjölkgård med ved, flis eller havre :

The background for my thesis is the fact that with rising electricity and oil prices it becomes interesting to calculate on alternative heating systems. I have chosen to calculate upon my parents? farm, which today heats the dwelling house with wood. This is very time-consuming work, time which could be spent on other work. The main objective for this study is to compare three different heating systems to decide how they differ considering effort and cost. The result from the calculations was that grain-heating system demanded the least amount of work, but the total cost was a little higher compared to chips heating. Chips heating required half as much work as today?s wood heating and had a little lower total costs compared with the corn heating. Which system to choose largely depends on how the own work is valued.

L?ggning av ett kils?gat br?dgolv

This bachelor thesis contains the findings of an investigation into the laying of wedge sawn wood flooring. The advantage of wedge sawn wood flooring is the usage of more material from each board reducing waste. The boards follow the natural profile of the tree where the root part of the board is wider, and the top part is narrower. The technique involves placing boards side by side with adjacent boards in opposite directions. The thick base of one board is neighbored by the narrow top of another, this creates a pattern of wedges in alternating directions, known as a ?root and top? system. Existing literature into this type of flooring is sparce.

Shelter use of horses during Swedish summer in relation to weather conditions and insect abundance

Outdoor housing of horses? best fulfils the horses? need for physical activity and it is an alternative to the more cost and energy demanding indoor housing in stables. Furthermore, if outdoor housed horses have access to shelter they can generally cope well with adverse weather conditions such as high or low ambient temperature, heavy rain or strong winds. In this study, the daytime shelter-seeking behaviour of three groups of horses housed outdoors was studied during the summer. The aim was to evaluate whether shelter use is related to weather variables (e.g., ambient temperature and wind speed) and insect harassment. The shelter-seeking behaviour was studied for three different groups of horses: Group 1) eight individually housed horses in paddocks that had access to three different shelter types (C: closed on three sides with roof, R: open on three sides with roof, W: closed on three sides without roof), Group 2) 25 group housed mares with foals on pasture with access to shelters C, and Group 3) ten mares without foals on pasture without access to shelter. Each group was studied for eight days.

Experimentell undersökning av provkroppar för trälimfogar

This thesis engages the topic of test methods for wood adhesives. Two test methods were evaluated, EN 302-1, a European standard, and ASTM D905, an American standard. The total amount of specimens manufactured and tested was more than 500. The adhesive bonds were tested in shear with an increasing load on the specimen until failure.The adhesives used were epoxy-resin, phenol-resorcinol-formaldehyde and a 2-K polyurethane. The test programme included five different types of intentional errors per method, in order to investigate the sensitivity of the test methods.

TOMO Hugglink

Tomo Hugglink (TOMO Skog) is an innovation for harvest and transport of biofuels. The system consists of a truck, a chipping unit and crane mounted on a link and a wood chip trailer. The system works in such a way that the chipping unit is disconnected and placed on the site and wood chips are loaded directly into the wood chip trailer.The aim of this study was:- To examine the performance of the TOMO Hugglink system under different conditions such as the size, placement and quality of the pile.- To calculate the cost per raw ton for two vehicle combinations at different transport distances and to examine the effect of a reduction in set-up time and an increase in load weight.- To identify possible improvements with the TOMO Hugglink system.A time study was conducted within the thesis work to make it possible to determine production and time consumption. In the subsequent economic analysis the cost per tone at different transport distances was calculated for two different lorry concepts. Furthermore the effect of a reduction in set-up time and an increase in load weight was calculated.Under current conditions the utilization of the chipper is low and only 29 % of the total system time is occupied by chipping.

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