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99 Uppsatser om Logs - Sida 1 av 7

Det gör ont när stockar spricker!

The aim of this study was to provide SCA Forest Norrbotten District with material to assist in their work towards decreasing the frequency of bucking splits in their saw timber Logs. SCA Forest supplies the Munksund sawmill with pine timber. Periodically the sawmill experiences problems related to bucking splits in their Logs. The purpose of this study was to find an available method to measure the occurrence of splits directly on incoming timber. The ambition was also to gain some knowledge about possible variations between different logging crews in terms of split frequency. If possible, this information could be used to investigate if certain crews produced more splits than others, and thereby making it possible to provide feedback to the logging machine operators. The study consisted of two major parts, a literature review, and a practical sawmill study.

Kapsprickor och avverkningsaggregat

This study was made for the Swedish forest company Sveaskog because the sawmills they delivered timber to had noticed a high frequency of bucking splits in their products. Coworker Jim Edström at Sveaskog also wanted to know if there was a big difference between different felling heads. The purpose with this study has been to find out the amount of bucking splits and if there is any felling head brand that did a bigger damage that the others. The study was made in two steps, where the first part was a literary review to find out results and conclusions in earlier studies. The best measuring method to check bucking splits was the known ?trissmetoden?.

Sorterar skotaren bort det timmer som skördaren har tillrett? :

The efficiency of the harvesters work is more often reviewed, than the work of the forwarders. In a local Stora Enso office the differences between the harvesters reported volume of timber, and the actual volume delivered to the industry had been noticed. Therefore, the decision was made to do a review on the forwarders work. The review was conducted together with a worker from Vmf Qbera, who is working daily with wood measurement, in order to get a valid evaluation of the Logs. Eight sites were included in the survey, and on each site 50 Logs were marked. Approximately one third of the marked Logs were pulpwood, and the remaining Logs marked were timber.

Förbättrat råvaruutnyttjande vid kvalitets-sortering av timmer : utvärdering av analysprogrammet Stockholmen för automatiserad timmersortering i dimensions- och kvalitetsklasser hos BARO WOOD AB

The aim of this thesis was to analyse BARO WOOD AB:s timber measuring and quality sorting and to evaluate the analyse program Stockholmen. The purpose was to get a better understanding for the quality sorting made at BARO WOOD AB today, analyse differences in center board quality from Logs with a good quality and Logs with a bad quality, suggest new sorting criterias developed from analyses made with Stockholmen and to evaluate the program Stockholmen. All analyses are based on data gathered in a test sawing made at BARO WOOD AB in June and July 2002. The test sawing was made on four different diameter classes and every diameter class consisted out of A or M-grade Logs, with a better quality, and B-grade Logs with a lesser quality. The Logs where sorted out with BARO WOOD AB:s existing quality criterias.

Hållfasthetssortering av plankor med hjälp av röntgendata

The aim of this thesis is to find a statistical model that sort Logs according to a predicted modulus of elasticity on the sawn boards. The input parameters for the model are X-ray variables from an X-ray scanner. For some of the log classes sawn at the sawmill it is desirable to have a narrow distribution of modulus of elasticity on the sawn boards. 250 pine Logs from five different diameter classes were numbered and followed through the sawmill process. Log data were collected from X-ray and 3-D scanners in the log intake.

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.

Förekomst & kostnad av kapsprickor i stormaskadad skog

The aim for this study where to investigate the frequency of cutting cracks in saw timber harvested in the storm-damaged forests in regions where the storms Hilde and Ivar hit. The idea for this work came from one of the region?s biggest actors, SCA Skog and Jämtlands district. The purpose where to find out how big proportion of the saw timber that contains cutting cracks, their financial cost in lost wood value and also give advice and suggestions on how to work against the frequency of cutting cracks. For the field-study some guidelines where used to make sure that the samples were taken under the same conditions, they were: ? The field-study must be performed under harvesting of storm-felled forest, which are horizontal/inclined trunks. ? The averaged sized tree will make it possible to harvest saw timber. ? The trunks can?t be root cut. A methodology called in Swedish ?Trissmetoden? was used because it is the most frequent used methodology in earlier performed studies and the only one that can be used I field. Under the field-study data were collected from 570 saw timber Logs, 30 Logs from each one of the tested harvesters.

Ändamålsanpassad TINA-sortering av sågtimmer :

Swedish sawmills of today suffer from unsatisfying economy with high costs and low benefits. The economical result depends on how well the sawmill can use their raw material. Iggesund Timber AB, a sawmill in the Holmen group, produces a large amount is enduse orientated products for the woodworking industry. Therefore the aim of this student thesis was to investigate the possibility of automatic enduse orientated quality grading of Scots Pine (Pinus sylvestris) saw Logs by using a gamma-ray log scanner. Iggesund Timber AB has the possibility to grade Logs automatically with TINA, a two way gamma-ray log scanner. Grading and classification of Scots Pine Logs in Sweden today are mainly manual but can in some rare cases be automatic.

Mätramar för vederlagsmätning och timmersortering på sågverk

The measuring of Logs is important in the sawmills process to the sawn products. The technology of automatic wood measurement is continuance developing. This study has the purpose to see how the different techniques and the routines works of measure frames for determining of wood value and sorting in sawmills. The study is performed as a literature study and a survey. The survey includes some of the Swedish sawmills that produce more than 10 000 cubic meters sawed products per year.

Talltimmeraptering - påverkande faktorer

In this work, I describe the factors that affect the bucking of pine Logs on the basis of the machine operator. The aim is to find an explanation why the bucking differs so greatly between requested length results and the actual length results in pine bucking. The used methods in this study were data from simulated pine outcomes, data from earlier length outcomes and analysis of the harvesters' PRI files. This is to identify the problem. To explain the background to the problems a qualitative research interview was used.

Qualities and supply of suitable dead wood for Ceruchus chrysomelinus and its dispersal pattern in a translocated population

The wood-living beetle Ceruchus chrysomelinus is a rare species connected to natural forests. In Sweden, it is red-listed as endangered (EN) and an action plan for its preservation has been done by the Swedish Environmental Protection Agency. In this work I have therefore investigated how a translocation of the species succeeded after 17 years. I aimed to study the species dispersal biology, its substrate preferences and the supply of suitable wood on this site. The study was performed during 2012 in Pansaruddens nature reserve close to Uppsala in Sweden, which is a spruce dominated forest.

Att läsa skönlitteratur : Gymnasieelevers arbete med att utveckla litterär kompetens

This study is based on my work as a teacher of Swedish language and literature to upper secondary school students, and my interest in developing the teaching of literature by using both new criticism theories and theories of literary perception focusing on reader response. The purpose of the study is to examine the learning process in trying to develop literary competence and to find out how to describe the competence shown by the students. My starting-point is a discussion about literary competence and the theory and model of literary competence by Örjan Torell. In examining literary competence, by how students use their constitutional competence as well as performance and literary transfer competences, Torell´s model shows the possibility and the need for both knowledge of literature and personal reception by focusing on the dialogue between author and reader.The method is qualitative and the empirics are material collected in one senior high school class in the Social Science programme during their second and third year. The material contains written reading Logs, written answers to tasks and transcribed recordings of discussions of literature.The analysis shows a variety among the literary competence shown and developed by the students and points to the complexity of understanding the concept of literary competence.

Uppföljningsverktyg för analys av användarloggar

In order to understand user behaviour and navigation patterns, user logging is today widely used in analysis and development of user interfaces. These user Logs tend to be quite many and can contain a lot of different data. A big issue is how to process and display this data in a perspicuous way to the stakeholder. This study is about how to develop a prototype to handle this issue. It was solved by various methods from human-computer interaction.

Färsk ved till Hallstaviks pappersbruk :

Hallstaviks papermill is an industry plant within Holmen Paper. Hallstavik is a mechanical mill and produce newspaper and journal paper. During year 2000, Hallstavik used approximate 1.200 m3f spruce, either as Logs or chips from sawmills. Due to that the production is running continuously the mill also needs raw material at the same rate. At some periods the supply of raw material cannot keep up pace.

Nattaktivitet hos Afrikanska elefanter (Loxodonta africana) i fångenskap med olika kombinationer av miljöberikning

African elephants (Loxodonta Africana) are kept all over the world in different kinds of enclosures. The enclosures are however often unsuitable for the elephants. Research has shown that elephants are nocturnal animals. Therefore it is important to keep elephants occupied, for instance by using enrichments, also at the night. Five elephants were studied at Borås djurpark, four elephants in one room and one elephant, named Nyoka, in one room.

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