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348 Uppsatser om Formation of cracks - Sida 1 av 24

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.

Temperatursprickor i ung betong : Utvärdering av projektering och utförande av åtgärder, samt utveckling av dimensioneringsmetod för kylsystem

The report contains three parts. The first part is a summary and overall presentation of thermalcracks and preventing measures against such cracks. This is a theoretical part where theinterested designer can get acquainted with various alternatives, be guided to more detailedliterature, and receive some practical information regarding the design of the respectivemeasures.The second part deals with calculation of the risk for thermal cracks and design of water coolingas a limiting measure. Two complementary methods are reviewed for efficient calculation:?the handbook method CraX1(by Lulea University of Technology) is used for quickverification?finite differential analysis in the calculationtool ConTeSt Pro for more precise projectingHere is also presented a development of existing standards through design of the cooling systemby means of the Bernoulli equation.

Deaktivering av metanisering katalysatorer

A titania-supported nickel catalyst was prepared and tested in methanation in order to evaluate its catalytic properties (activity, selectivity and specially, activity loss), and compare it with an alumina-supported nickel catalyst.The titania-supported catalyst did not only show higher stability than alumina, but also presented a different cause of deactivation, carbon formation. In addition, a kinetic model was obtained for the titania-supported catalyst, and a study of the effect of different operating conditions (temperature, composition and partial pressures of synthesis gas and water) on the deactivation rate and carbon formation of this catalyst was performed.

Är variation i STFI-tjocklek ett bra mått på kartongs bulighet? : Are variation in STFI-thickness a good measure of uneven surface, bumpiness, on cardboard?

This degree project aim to evaluate if variations of the STFI thickness can be used to assess bumpiness on cardboard. During the project cardboard samples were measured using Bendtsen, PPS, a L&W formation tester, OptiTopo, Ambertec formation, the STFI thickness tester and a visual comparison. The different methods were then compared to see if there is any correlations between them. The results showed that the visual comparison and OptiTopo correlates. The STFI thickness tester shows however no correlation with the OptiTopo and visual comparison, thus aren't suitable measuring bumpiness..

Karolinsk Stridstaktik : artilleriets och pikens roll 1700-1712 samt bataljonens stridsformering

From a new perspective, this paper will examine the artillery and the pike role in the period 1700-1712 and the battalion´s battle formation in the Caroline combat tactics. Carolinian battle tactics were practiced during the period 1700-1721. The results from my study will be compared to existing research opinion regarding the selected subject areas, if the result confirms the thesis or question the existing research opinion. The source material used consists of eyewitness accounts from the period consisting of diaries, memoir, biography, general muster rolls and historical literature covering the subject. The analysis shows that the Caroline artillery took part in 12 battles during the period of 1700-1712.

Vibrationsproblem i närliggande konstruktioner i samband med markarbete

Ground work like blasting, piling and excavation has always had a great influence during the planning phase of a construction project since it can cause damages on adjacent buildings and have severe economic consequences. This thesis deals with how vibrations caused by ground work influence near-by buildings and what methods geotechnicians and construction entrepreneurs use to handle these risks.The purpose of this thesis is to explain risk management in relation to ground work. In order to achieve this I have used a qualitative method by interviewing a geotechnician and a ground work contractor who possess knowledge and experience useful to this thesis. The result shows that vibrations from ground work spread through the ground as seismic waves that cause displacements and packing in the ground visible in adjacent buildings as cracks and subsidence damages. Geotechnicians study ground work vibrations by means of ground investigations and experience from previous projects in order to produce a risk analysis that entrepreneurs can use to reduce damages.

Kraftspelsanalys av transportstag : Prefabricerade väggelement i betong

A titania-supported nickel catalyst was prepared and tested in methanation in order to evaluate its catalytic properties (activity, selectivity and specially, activity loss), and compare it with an alumina-supported nickel catalyst.The titania-supported catalyst did not only show higher stability than alumina, but also presented a different cause of deactivation, carbon formation. In addition, a kinetic model was obtained for the titania-supported catalyst, and a study of the effect of different operating conditions (temperature, composition and partial pressures of synthesis gas and water) on the deactivation rate and carbon formation of this catalyst was performed.

Bergerosion i utskovskanaler

Today?s climate changes will probably give rise to precipitation in Sweden, which will cause more floods in Swedish rivers. Many of the Swedish rivers are regulated and have lots of hydro-electro power plants. Higher floods in the rivers will give greater water loads on the dams, which mean that a higher discharge through the sluice gates and in the spillway channels is needed. High discharge of water in a spillway channel can create scour of the material in the channel.

?Oh shit, kan jag få skägg?? : -

The aim of this study was to explore transsexuals? identity formation and experiences related to cross-sex hormone treatment, as well as to become absorbed in the narrative approach. To be able to participate in transsexuals? identity formation, life stories were well suited as a theoretical approach. Life stories can be seen as socially situated actions according to Mishler, where individuals? identity formation can be seen as both identity performances and identity claims.

Man måste inte tro nånting ? men man måste samtala : Ärkebiskop KG Hammars syn på kommunikation och språk

Archbishop KG Hammar has attracted attention for his liberal position in theology. His view on the role of language and communication is central in several books and articles he has published as leader of the Church of Sweden. One of his main theses is the fact that meaning is created in the encounter between text and reader. He often reiterates: God is relation. This non-traditional dynamic stance has a broad impact not only on theology.

Lycksabäcken, ett riksintresse med komplext deglaciationsförlopp : Presentation av ett möjligt scenario över deglaciationen i området

The area of Lycksabäcken northwest of Lycksele is a national interest of natural conservationbecause of its geological values with many unique landforms. Many of these landforms indicatethat the deglaciation process in the area was very complex. However, the deglaciation process inthe area has not previously been fully understood. The aim is to add to the knowledge of theevents that took place during the last deglaciation. To do this, the glaciofluvial landforms in thearea were mapped by studying aerial photographs with a Wild Aviopreter and a five-day fieldinventory of key areas for the interpretation.

Bacterial contamination of eggshells in deep litter floor systemsand conventional cages in Jordan

This study was carried out in Jordan with the purpose to investigate the bacterial microflora of egg shells from cage systems and from deep litter floor systems. Another aim wasto get a general impression of the hygiene, at farm level, of egg production in Jordan andthe factors affecting it.Eggs from two cage systems and three floor systems were analyzed, regarding bacterialcontamination of the egg shells. Egg samples were taken from the storage room, the eggcradle in the cage system and from the nest and floor in the floor system. To get a generalimpression of the hygiene at the farms, swab tests and air tests were performed. Swab testswere performed with a sterile cotton swab at the same units as the eggs were sampled andair tests were performed by opening petri dishes where the hens were staying.

Oosporbildning av Phythophthora infestans i potatis och bägarnattskatta

Potato late blight is one of the most important potato diseases worldwide. The disease is caused by an oomycete called Phytophthora infestans. The host range of P. infestans includes potato (Solanum tuberosum) and hairy nightshade (Solanum physalifolium). Hairy nightshade has recently established itself as an important weed in the southernmost part of Sweden.

"Inte som alla andra" : En kvalitativ studie om en grupp vuxna med Asperger syndrom

Normal children acquire the necessary social habits without being consciously aware of this, they learn instinctively. (Author?s translation from Swedish to English) (Asperger & Frith, 1998, s. 21) This essay is about people who do not learn to socialize, the social habits, instinctively but through conscious learning. We have interviewed three adults with the diagnosis of Asperger syndrome with the aim to let them tell us about what it means to have a neuropsychiatric disability.

Hur maten blev begriplig : En analys av matens diskursiva formationen bland Slow Foodmedlemmar i Göteborg

The aim of this essay is to analyze the discursive production of Food, within the Slow food movement, by its members. Through a discourse analysis inspired, theoretically and methodically, by Michel Foucault, this essay examines how the idea of food ? that is ?what should be eaten? ? in opposite to what can be eaten, is constructed within by Slow Food members in the Gothenburg area. The essay analysis how Slow Food?s food discourse is structured and what results this formation has on food within this discourse.

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