No description available.

This study discusses the behavior of people towards natural language interfaces. It draws parallels to the behavior of people towards other people, and discusses how far these parallels can be stretched. A small experimental study of users performing tasks using a natural language interface to a database is presented, and the results related to the discussion. The main points made are 1) that new modalities like the one used in typical human computer interaction - written interactive communication - are problematic for new users, from lack of conventions; and 2) that users' attitudes towards computers and of the system's linguistic and other competence shape much of the interaction, and that these attitudes change, and that thus the important factor to take into account in system design is not what the initial attitudes are but rather what the process of changing them is and how to utilize the process of change to teach the user the system language and interaction modality. / <p>QC 20160530</p>

No description available.

The sealing of hard jointed rock by grouting involves several complicated mechanical systems. The result is a complex coupled system of hydro- logical and mechanical precesses. In order to determine the higher order effects of the resulting system the fracture deformations must be assessed. This requires a model that mimics the mechanical behaviour of not only fractures under normal load but also the entire rock mass system. This model indicates that there are two dominant regimes involved; a permeation regime and a high pressure regime. The pressure limit that separates permeation grouting from high pressure grouting can then be found to be closely related to the in situ stress. In the high pressure regime the deformations may be large but very situation-dependent. The principal deformational eigenmodes of some boundary conditions are considered. The analysis indicates that the usage of high pressure grouting can be both benficial to the operation as well as increase the inflow of water to the excavation. / QC 20101115

QC 20110617

Lignocellulosic biomasses are an important source of chemical components such as cellulose, lignin and hemicelluloses, and can be used for a variety of purposes in both the pulp and paper and chemical conversion industries. Xylan, the main hemicellulose found in hardwood and grass plants, plays an important role during the pulping/pretreatment process reactions, including those used in 2nd generation bioethanol production. It may also play an important role in the production of certain novel materials. This thesis evaluates the composition of eucalyptus (Eucalyptus urophylla x Eucalyptus grandis), sugarcane bagasse and sugarcane straw, with a specific focus on the structure and properties of xylan. The chemical characterization of biomasses showed that sugarcane bagasse and straw contain larger amounts of extractives, ash and silica than eucalyptus. The large amount of silica leads to an overestimation of the Klason lignin content, if not corrected. By using a complete mass balance approach, sugarcane bagasse and straw were shown to contain smaller amounts of lignin (18.0% and 13.9%, respectively) than previously reported for these raw materials, and certainly a much smaller amount of lignin than was found in eucalyptus (27.4%). The hemicellulose content in sugarcane bagasse (28.7%) and straw (29.8%) was much higher than that in eucalyptus (20.3%). In order to investigate the structure of the xylan in greater detail, it was extracted with dimethyl sulfoxide from holocellulose, obtained by either peracetic acid or sodium chlorite delignification. The structure of the isolated xylans was confirmed by FTIR and 1H NMR analysis. In eucalyptus, the O-acetyl-(4-O-methylglucurono)xylan (MGX) was identified. This had a molar ratio of xylose units to branches of 4-O-methylglucuronic acid of 10:1.1 and a degree of acetylation of 0.39. All 4-O- methylglucuronic acid groups were attached to position O-2 of the xylose units, which had an acetyl group in position O-3. The acetyl groups were distributed in positions O-3 (64%), O-2 (26%) and O-2,3 (10%). The MGX had a molecular weight (Mw) of about 42 kDa. In bagasse and straw, arabinoxylan (AX) was identified. This had a molar ratio of xylose units to arabinosyl substitutions of 10:0.5 for bagasse and 10:0.6 for straw. A degree of acetylation was 0.29 and 0.08 for bagasse and straw, respectively. The arabinose units were attached preferentially to position O-3 in AX. In the xylan from bagasse, the acetyl groups were found in positions O-3 (60%), O-2 (13%) and O-2,3 (27%), while in the xylan from straw, the acetyl groups were distributed between positions O-3 (67%) and O-2 (33%). The AX had a molecular weight (Mw) of about 38 kDa and 30 kDa for bagasse and straw, respectively. The differences in the structure of xylan present in the various biomasses played an important role during hydrothermal pretreatment, which is often used as the first step in 2nd generation ethanol production. The varying amounts of uronic acid and acetyl groups resulted in different starting pH levels of liquor and, thus, affected the chemical transformation in the biomasses in different ways. The hydrothermal pretreatment resulted mostly in the removal and/or transformation of hemicelluloses, but also in the formation of a significant number of pseudo-lignin structures. In addition, in eucalyptus, pseudo-extractives structures were generated. The sugarcane straw showed the highest mass loss during the investigated pretreatment. / <p>QC 20151023</p>

Good sound insulation is highly valued by Swedish tenants. To be able to achieve that, one must look at many aspects, such as room volumes, floor planes, flooring, but also what materials that are to be built with and how it ́s constructed.  The use of cast-in ventilation ducts in the load-bearing structures is a common method in Sweden. This is a method that is well suited when large residential houses in concrete are to be built and you want a flexible way to lead the ventilation ducts in the building without them taking up unnecessary space or having to be led longer distances than necessary.  At present, WSP acoustics in Umeå uses two different methods with reasonable assumptions to calculate the impact of cast-in ventilation ducts on airborne sound insulation, but they wish to verify which of the methods is most reliable. In one method, the wall with the ducts is thought of as a hollow core slab with the same corresponding weight as the actual wall. In the second method, the weight lost at the channels has been calculated and then the wall depth is reduced accordingly. The purpose is to evaluate whether these approximate calculation methods regarding the impact of embedded ducts on airborne sound insulation are consistent with the results of field measurements.  Field measurements show that the airborne sound insulation becomes gradually worse with an increased number of ducts, and this is most clearly seen in the range between 400 and 3150 Hz. The methods do not differ by more than 1 dB in weighted standardized sound level difference compared to the field measurements and can therefore both be used in designs. The comparison between the calculation methods shows that both give equivalent results, but the method with reduced wall depth is recommended. / God ljudisolering i sin bostad värderas högt hos hyresgäster i Sverige. För att uppnå detta måste många aspekter beaktas som till exempel planlösning, rumsstorlek, golvbeläggning, men inte minst vilket material som ska byggas med och hur konstruktionerna är uppbyggda.  Att använda sig av ingjutna ventilationskanaler i de bärande konstruktionerna är en vanlig metod i Sverige. Det är en som metod lämpar sig väl när stora bostadshus i betong ska byggas och det önskas ett smidigt sätt att leda ut ventilationskanalerna i byggnaden utan att de tar onödig plats eller behöver ledas längre sträckor än nödvändigt.  I dagsläget använder sig WSP akustik i Umeå av två olika metoder med rimliga antaganden för att beräkna ingjutna kanalers påverkan på luftljudsisolering. De önskar verifiera vilken av beräkningsmetoderna som är mest tillförlitlig. I den ena metoden approximeras väggen med kanalerna som ett håldäck med samma motsvarande tyngd som den verkliga väggen. I den andra metoden räknas tyngden som förloras vid kanalerna bort och väggdjupet reduceras sedan efter det. Syftet med denna rapport är att utvärdera huruvida approximativa beräkningsmetoder gällande ingjutna kanalers påverkan på luftljudsisolering, överensstämmer med resultatet från fältmätningar.  Fältmätningarna visar att luftljudsisoleringen blir sämre med ökat antal kanaler och det framgår tydligast i spannet mellan 400 och 3150 Hz. Metoderna skiljer sig inte mer än 1 dB i vägd standardiserad ljudnivåskillnad mot fältmätningarna och kan därför båda användas i projekteringar. Jämförelsen mellan beräkningsmetoderna visar att båda ger likvärdiga resultat, men metoden med reducerat väggdjup rekommenderas.

Detta arbete är genomfört med målet att tydliggöra hur en byggnads miljöbelastning kan reduceras. I en fallstudie av ett flerbostadshus i Gävle jämförs miljöbelastningen med hänsyn till utsläpp av koldioxid, övergödning och försurning. En komprimerad LCA utförs från två olika fall där den bärande stommen genomgår en förändring av betongväggar till väggar av korslimmat trä. Huset som utgör objekt för arbetet är hämtat från en vetenskaplig artikel som är gjord med syftet att jämföra de bärande egenskaperna hos trä- och betongväggar. Den komprimerade LCA:n har gjorts med mjukvaran One Click LCA som är ett beräkningsverktyg med fullt stöd för de krav och certifieringar som berör arbete med LCA. Resultatet visar tydligt att bytet till träelement i stommen bidrar till ett reducerat utsläpp och vidare så finns det stora miljömässiga besparingar att göra vid större utnyttjande av trä i konstruktioner. / This work is conducted with the aim of making clear how a building's environmental impact can be reduced. In a case study of an apartment building in Gävle, the envi-ronmental impact is compared with regard to carbon dioxide emissions, eutrophica-tion and acidification. A compressed LCA is performed from two different cases where the load-bearing frame undergoes a change of concrete walls to walls of CLT panels. The house that is the subject of the work is taken from a scientific article made for the purpose of comparing the load-bearing properties of wooden and con-crete walls. The compressed LCA has been made with the One Click LCA software, which is a calculation tool with full support for the requirements and certification that concerns work with LCA. The results clearly show that the change to wooden elements in the frame contributes to a reduced emission and furthermore, there are large environmental savings to be achieved with greater utilization of wood in struc-tures.

For recent years, silica aerogel has attracted great attention and been extensively used in different technical fields owning to its remarkable properties in optics, mechanics, acoustics etc. especially in thermology. The thermal conductivity of a number of different insulation materials has been measured both by Transient Plane Source (TPS) and a new designed experiment−Guarded hot plate method respectively. It turns out that silica aerogel has the lowest thermal conductivity value of 0.0144 W/mK and accordingly the highest thermal resistance among all those common insulation materials which makes it a good choice in buildings insulation industry. Besides, the energy-saving and heating-cost of silica aerogel used as building insulations is calculated by the method of Life cycle cost analysis method (LCCA), and the result shows silica aerogel can help to reduce the annual heat loss of a building by 50.9% and also help to reduce about half of the annual heating costs when compared with other insulations. Due to the excellent thermal performances, however, silica aerogel has much higher selling prices (75.24 US$/m2) than the other normal insulation materials, and then a comparatively longer payback time (3.54 years) has to be taken than the other competitive solutions (0.22 years for EPS, 0.07 years for XPS, etc.). And the feasibility of using silica aerogel as building insulations is discussed.

During the years of development in the 60s and 70s the need for new housing in Sweden arose. Sweden was going to be the most modern country in the world. This period has later been called “the time of the big programmes”. One of the parts in this building of a welfare society was a large policy of building politics with few counterparts in history. This large scale production of new housing required new systems of production, planning and organization.The housing blocks which was the result of this and that today represents 25% of the total infrastructure in Sweden, is called “the million programme”.The goal was to solve the severe problem of lack of housing and during a short time build a one million apartments to improve the standard of living. The majority of dwellings were to be apartments but many villa neighborhoods were also counted among “ the million programme”.During the time of the million program approximately 1 000 600 dwellings were built. This programme has come to represent the goals of that period and the esthetic visions. As a consequence a lot of old houses that no longer held the acquired standards were torn down.So even though “the million programme” was completed we are still in need of apartments in those areas.Therefore we have chosen to analyse and explore the possibilities of expansion of existing buildings on a location in Stockholm. The reason for this project is to analyse, organize and suggest the best course of action to take during an expansion of these apartments. These expansions will be roof apartments and we will look into the possibilities. We will consider architecture and construction on these buildings.During the course of this project we have become convinced that by using the construction methods that we have analyzed and concluded in our project, you will be able to increase the effectiveness of expansions on buildings of “the million program”.