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Reviews the existence of abnormalities of perception in autism and argues that cortical maps for feature recognition are impaired in autistic individuals. Suitably chosen artificial neural networks are mathematical models of individual neurons and their connections, albeit simplified in several ways. Computer simulations of these models may yield insights into the impairments of the brain. A self-organizing map constitutes a structure which upon training becomes sensitive to features in the stimuli. Successful development of a feature map demands proper lateral feedback. If the inhibitory component is strong the neural columns become narrowly focused, that is, variability in the different features is not accepted if features are to be recognized. If the inhibitory component becomes excessive, feature maps will not develop. The author states that narrowly focused or undeveloped feature maps have relevance in explaining autism.
N/A / Link / Gustafsson , Lennart / 1997

Luleå tekniska universitet Övrigt
 Carla Ravaioli (with a contribution by Paul Ekins) London, Zed Books, 1995, 212 pp, ISBN 1-85649-278-8 . Review
N/A / Link / Söderholm , Patrik / 1995

N/A / Link / Brändström , Sture / 1990

Luleå tekniska universitet Övrigt
N/A / Link / Berg , Elisabeth / 2000

Luleå tekniska universitet Övrigt
The general interest of this research is problems concerned with new information and technology, and their development and use in the management context. One important aspect of this problem has been argued to be how people come to make sense of new information and technology. The literature have claimed that sensemaking can be understood as a process of activities taking place either in mind, in language, and in interaction. Only the fact that we think, talk and write, and interact is not sufficient answers to what sensemaking is. The main argument in this study is that the notion of sensemaking is unclear and needs to be further investigated, both theoretical and empirical. The motivation for this is its importance for appropriate, competent and efficient management in small organizations. The study: (1) describe, discuss and classify sensemaking based upon the literature; (2) develops a theoretical model of sensemaking; (3) develops a research plan for further investigation of the theoretical model; (4)evaluates the research plan and the theoretical model with support of two pilot cases; (5) discuss management implications from a sensemaking perspective.
N/A / Link / Ifvarsson , Christian / 2000

Palaeomagnetic data are used to study the configurations of continents during the Proterozoic. Applying stringent reliability criteria, the positions of the continents at 12 times in the 2.45- to 1.00-Ga period have been constructed. The continents lie predominantly in low to intermediate latitudes. The sedimentological indicators of palaeoclimate are generally consistent with the palaeomagnetic latitudes, with the exception of the Early Proterozoic, when low latitude glaciations took place on several continents. The Proterozoic continental configurations are generally in agreement with current geological models of the evolution of the continents. The data suggest that three large continental landmasses existed during the Proterozoic. The oldest one is the Neoarchaean Kenorland, which comprised at least Laurentia, Baltica, Australia and the Kalahari craton. The protracted breakup of Kenorland during the 2.45- to 2.10-Ga interval is manifested by mafic dykes and sedimentary rift-basins on many continents. The second ‘supercontinental' landmass is Hudsonland (also known as Columbia). On the basis of purely palaeomagnetic data, this supercontinent consisted of Laurentia, Baltica, Ukraine, Amazonia and Australia and perhaps also Siberia, North China and Kalahari. Hudsonland existed from 1.83 to ca. 1.50-1.25 Ga. The youngest assembly is the Neoproterozoic supercontinent of Rodinia, which was formed by continent-continent collisions during ≈1.10-1.00 Ga and which involved most of the continents. A new model for its assembly and configuration is presented, which suggests that multiple Grenvillian age collisions took place during 1.10-1.00 Ga. The configurations of Kenorland, Hudsonland and Rodinia depart from each other and also from the Pangaea assembly. The tectonic styles of their amalgamation are also different reflecting probable changes in sizes and thicknesses of the cratonic blocks as well as changes in the thermal conditions of the mantle through time.
N/A / Link / Pesonen , L. J. / 2003

Palaeomagnetic data from Fennoscandia ranging from the Archaean to the Tertiary have been compiled into a catalogue. The data are presented in table format, listing Precambrian data according to tectonomagmatic blocks and Late Precambrian-Phanerozoic data according to geological periods. Each pole is graded with the modified Briden-Duff classification scheme. The catalogue (complete to the end of 1988) contains 350 entries from 31 tectonomagmatic blocks and/or geological periods. Normal and reversed polarity data are listed separately to allow polarity asymmetries to be studied. Each entry also has an indexed abstract summarizing relevant information, such as the age of the rock, the age of the natural remanent magnetization and the basis for the assigned reliability grade. All the data are stored in the palaeomagnetic data bank, which will be updated annually with new data. The catalogue is the basic source of data for the microcomputer-based palaeomagnetic database for Fennoscandia now being compiled.
N/A / Link / Pesonen , L. J. / 1991

Before the deposition of a Proterozoic cover and the repeated Proterozoic reworking of the older rocks, the presently exposed Archaean areas in northern Sweden formed part of a coherent craton. In the present study, we have used Sm---Nd isotopic analyses of Proterozoic granitoids and metavolcanics to delineate the Archaean palaeoboundary. In a regional context, the transition from strongly negative εNd(t) values in the northeast to positive values in the southwest is distinct, and approximately defines the border of the old craton. The Archaean palaeoboundary extends in a WNW direction, and is subparallel to the longitudinal axis of the Skellefte sulphide ore district but it is situated ≈ 100 km farther to the north. The ≈ 1.9 Ga old granitoids on the two sides of the palaeoboundary were all formed in compressional environments, but those situated to the north have higher contents of LILE and LREE at similar contents of Si. This indicates that they were generated in an area with thicker crust and supports thelocation of the Archaean-Proterozoic palaeoboundary. There is no simple correlation between the Archaean palaeoboundary, as defined by the isotopic results, and any of the major fracture systems as interpreted from regional geophysical measurements. Reflection seismic work indicates that juvenile volcanic-arc terrains to the south have been thrust onto the Archaean craton. Possible thrust faults have been identified from aeromagnetic measurements. Rifting of the Archaean craton created a passive margin ≈ 2.0 Ga ago. Spreading shifted to convergence with subduction beneath the Archaean continent ≈ 1.9 Ga ago. Subsequently, the resulting juvenile volcanic arc collided with the old continent, and the Archaean palaeoboundary as existing today was formed by a collision characterized by overthrusting. The boundary then was disturbed by later deformation predominantly along NNE-trending fracture systems.
N/A / Link / Öhlander , Björn / 1993

N/A / Link / Abeysekera , John / 2000

Luleå tekniska universitet Övrigt
Since its formal inception more than half a century ago, ergonomics has time and again demonstrated that it has a niche among the held of scientific disciplines aspiring to make the world a better place. How far has it really gone? Can we now lay claim that it is indeed well-known and accepted? Are the benefits it purports to deliver realized in all parts of the world? About two-thirds of human beings live in the Third World. This is where poverty and inequality are relatively more common. This is where much work is still degrading and far from being humane. This is also where ergonomics has yet to make its presence felt in practice. This paper attempts to show that ergonomics can and will become a globally applied science. However, it has to make its contribution to the Third World prevalent and long-lasting. The paper focuses on the current state of ergonomics in the Third World, the so-called Industrially Developing Countries (IDCs).
N/A / Link / Shahnavaz , Houshang / 1996

Technological development has contributed to economic growth and social progress as well as a reduction of many sources of occupational accidents, injuries and stresses. However, advanced technology has also brought new sources of work stress and injuries. Industrially developing countries (IDC) have tended to try to achieve economic growth and development by importing technology designed for IDC. However, because of several complex technical, cultural and socio-economic factors, this policy has not been always successful. Inappropriate technology transfer has led to many work environment and productivity problems. Consideration of ergonomics in the choice and utilization of the transferred technology can help to create a good fit between technology, technology users and the operating environment. Application of ergonomics is, however, not widely spread in most IDC. Ergonomics input will create the appropriate working environment in which people are safe and motivated to participate and can better utilize company resources for increasing system productivity, reliability and availability.
N/A / Link / Shahnavaz , Houshang / 2000

Five different types of cold protective footwear have been tested with regard to their resistance to dry heat loss (i.e. the insulation) with a new electrically heated foot model. The model is able to simulate ‘walking' movements in order to provide a more realistic simulation of wear conditions. Thermal insulation of shoes with and without a steel toe cap was the same. The insulating properties during simulated walking movements were 10-25% lower compared with static conditions. For two of the shoe models a significantly lower insulation value for the sole area was obtained when adding a weight of 30 kg. A significant difference could also be found between the insulation values of two different sizes of one of the models. Measurements with the standard method (EN 344) correlated well with the local insulation value of the sole part of the thermal foot. Correlation with the insulation value for the whole shoe was much less, variation was bigger and ranking in terms of cold protection differed between methods.The electrically heated foot model appears to provide a reproducible, accurate and more realistic method for measuring the insulation properties of shoes than EN 344.
N/A / Link / Bergquist , Karin / 1997

Luleå tekniska universitet Övrigt
N/A / Link / Nilsson , Mats / 1996

As the industrial production of minerals and metals increases, the amount of wastes becomes an environmental problem that must be delt with. It is imperative for the future to that these materials are regarded as resources to be utilised in other industries. The first step in this investigation was to find reliable methods of evaluating the effect of specific products on the properties of concrete within a reasonable timeframe. A test procedure consisting of easy and reliable experimental methods is important, since a by-products reaction in the cement system can not be predicted by its chemical analysis. Materials can have the same chemical components but still react in different ways, and it is therefore imperative that materials with desirable properties can be separated from materials with undesirable ones. The second step was to investigate the influence of quartz filler on concrete properties. Quartz was chosen as filler since it can be considered an inert material. Fillers interact with the cement in several ways. They may be chemically inert but can still indirectly influence the chemical structure of the cement paste and concrete in a positive way. Fillers can also replace cement and be used to improve rheological properties, which in turn will influence the properties of the hardened concrete.
N/A / Link / Moosberg , Helena / 2000

Informations- och kommunikationstekniken har för många människor blivit en naturlig och viktig del i deras dagliga liv. Den öppnar för stora möjligheter men kan också innebära stora omställningar för människor. En återkommande fråga i den allmänna debatten är om alla människor i samhället kommer att kunna ta del av denna teknik. Flera studier och utredningar har visat att människor med funktionshinder är diskriminerade och marginaliserade i samhället på olika sätt. Det finns stora brister i synsätt på, attityder till och bemötande av människor med funktionshinder. Bristerna är stora även beträffande tillgängligheten, såväl när det gäller den fysiska miljön som tillgången till information och möjligheterna till kommunikation. De flesta funktionshindrade är vuxna och de är i större utsträckning utanför arbetsmarknaden och omfattas inte i lika stor utsträckning av de datorsatsningar som görs i skola och arbetsliv. I licentiatuppsatsen avhandlas informations- och kommunikationsteknikens betydelse för människormed funktionshinder i Norrbottens glesbygd. I studien redovisas och analyseras en modell som har utvecklats i ett EU-projekt, EuroConnect, vid Luleå tekniska universitet. Projektet var ett samarbete mellan universitetet, Länsstyrelsen, Landstinget, Kommunförbundet, Länsarbetsnämnden, Försäkringskassan samt HSO Norrbotten (Handikappföreningarnas samarbetsorgan). Målgruppen var kvinnor och män i Norrbotten i olika åldrar, med olika typer av funktionshinder och utan tidigare vana att använda dator för kommunikation och informationssökning. I projektet fick deltagarna möjlighet att lära att använda datorn för kommunikation och informationssökning, enligt en individuellt upplagd plan. Träffar på universitetet varvades med datoranvändning i hemmet. En viktig ambition var att deltagarna successivt själva skulle bli aktörer och delta i projektet på olika sätt utifrån förmåga och behov. Resultatet visar att datorn blev ett viktigt och användbart verktyg för deltagarna. Efter vunna kunskaper om användning av informations- och kommunikationstekniken, kunde deltagarna på egen hand utifrån sina intressen och behov kommunicera med omvärlden. Denna möjlighet visade sig vara mycket viktig för människor med funktionshinder. Deltagarna var aktiva och delaktiga i projektets framväxande och ansvarade för många arbetsuppgifter i projektet. Alla deltagarna utom en fortsatte att använda datorn efter projektslut. En slutsats är att datoranvändandet gett människor med funktionshinder en möjlighet att påverka sin livssituation.
N/A / Link / Gardelli , Åsa / 2000

Remediation of mine waste by the application of till cover is one of the more common methods used in Sweden to prevent oxidation of sulphide-rich minerals. Although the general conclusion from Swedish state-of-the-art field studies is that dry covers may be effective, they are expensive to construct. Further investigations are also needed to understand the processes occurring in till covered waste deposits. The Kristineberg mining area has been chosen as the main field site for the research program MiMi (Mitigation of the environmental impact of mining waste) funded by the Foundation for Strategic Environmental Research (MISTRA). MiMi focuses on finding new and improved methods to mitigate the environmental problems related to mining operations and disposal of mining waste. An extensive sampling programme was carried out in Kristineberg during 1998 and 1999. The Kristineberg mine is a Boliden mine, located within the Skellefte ore field. It is a Zn-Cu deposit developed in the 1940s and still in production. This thesis consists of three papers outlining the geochemical conditions prevailing in tailings Impoundment 1 at the Kristineberg mine, after remediation by applying till cover. The impoundment investigated was in use until the early 1950s and it was remediated in 1996. Two different remediation methods have been used; in the area with a shallow groundwater table 1.0 m of till was used to raise the groundwater table above the tailings. In other areas, with a deeper groundwater table, a sealing layer consisting of a 0.3 m thick layer of a compacted clayey till underlying a 1.5 m thick protective cover of unspecified till was used. Field studies include sampling of solid tailings, saturated tailings pore water as well as pore water from the vadose zone. Laboratory investigations consist of a five-step sequential extraction on solid tailings samples. Pre-remediation oxidation has resulted in a zonation of the tailings with an upper oxidised zone above unoxidised tailings. Just below the oxidation front, there is a secondary enrichment of especially Cu but also of other elements. Metals released by sulphide oxidation were thus secondarily enriched. Tailings remediated by the combination of a till cover and a raised groundwater table, resulted in a remobilisation of metals around and a few metres below the former oxidation front. Although the concentrations of several elements still are high in the pore water, they are lower than before the remediation. The general conclusion is that the remediation has succeeded in preventing further oxidation in this part of the impoundment. Sequential extractions performed on selected samples from the drilling of the impoundment show that most of the remaining sulphide-associated trace elements in the oxidised zone still belong to the sulphide fraction. At the level of the peaks of metal concentrations in the pore water (and the solid secondary enrichment) substantial concentrations of the trace elements Cd, Co, Cu, Ni, and Zn is present in the adsorbed/exchangeable/carbonatefraction. Other trace elements are retained with other secondary formations such as amorphous or crystalline iron oxyhydroxides e.g., As, Ba, and Pb. Especially the adsorbed/exchangeable/carbonate fraction is easily dissolved and the raised groundwater table remobilise these trace elements into the pore water, as could be seen from the pore water extractions. In Impoundment 1, where the sealing layer was applied, sampling of the infiltrating water was performed by tension lysimeters. Tension lysimeters were installed in the protective till cover, in the oxidised tailings, in the uppermost unoxidised tailings and at an intermediate depth. The groundwater at the same location was also sampled. The tension lysimeters in the till protective cover contained relatively low concentrations of most elements. Elements such as Al, Cd, Co, Cu, Fe, Mn, Ni, S, Si, and Zn had the highest concentrations in the second tension lysimeter in the tailings. Between the second and the third tension lysimeters the concentration of most elements decreased. The increase between the first and the second tension lysimeters can be explained by remobilisation of secondarily retained oxidation products. The decrease between the second and the third tension lysimeters is interpreted as co-precipitation with different iron oxyhydroxides as well as adsorption onto secondarily formed minerals and primary mineral surfaces. Between the deepest tension lysimeter and the groundwater table, the element concentrations decrease further. Most of the pre-remediation oxidation products that are secondarily retained below the oxidation front and are released by the small amount of infiltrating water, is tertiarily retained during continued downward transport. Thus, if the depth to the groundwater table is large enough, the metals released by infiltrating water do not reach it.
N/A / Link / Carlsson , Erik / 2000

Luleå tekniska universitet Övrigt
This thesis consists of four self-contained papers, divided into two parts where the first part considers issues in economics and the second discusses spatial issues in econometrics. In paper [1] the different waste disposal options, with emphasis on recycling and incineration, is examined and evaluated, using earlier research. This paper concludes that the literature reveals a range of results regarding the economics of waste paper recycling and incineration, respectively, and that the conceptual and empirical basis on which to determine efficient waste paper policy is still seriously incomplete. The effort in paper [2] is to identify and analyze determinants of inter-country differences in recovery and utilization rates, respectively. The paper concludes that the degree to which policy can affect these rates are limited since relative waste paper recovery and use are largely market-determined, and consequently depend on long-standing factors such as population density and competitiveness in the world market for paper and board products. Paper [3] explores the differences in inferences that one would draw from different econometric models in a spatial econometric setting. The study notes that ordinary least squares to a very large extent produce biased estimates due to spatial correlation in the data set. Hence, one would draw very different inferences from ordinary least squares and general spatial model estimates. Finally, paper [4] builds on paper [3] but explores some Bayesian estimation methods, i.e. heteroscedastic models, which take into account non-constant variance or spatial outliers. The data set used in these studies were limited because of censoring. The objective of this paper was to obtain Bayesian estimates that account for outliers and sample censoring. We found that ignoring the spatial autoregressive nature of the data, outliers and sample censoring would produce different inferences than the Bayesian models.
N/A / Link / Berglund , Christer / 2000

This article concentrates on problems of native peoples in the context of technical change moulded by institutionalized racism. External specialists are often imparted to developing countries in order to introduce advanced technology as well as to organize and run the administration. Native workers are presumed to gain know-how from work experience and take over management and professional jobs gradually as they learn from the foreign professionals. However, this strategy may suffer from conflicts between the foreign professionals and natives due to different cultures and ethnic backgrounds. Learning processes are undermined by these conflicts creating mistrust and lack of confidence. These conflicts often develop into institutionalized racism involving organized forms of exclusion such as overvaluation of formal education as opposed to native knowledge. The result is permanent reproduction of the need for imported specialized labour and 'destructive forgetting' of local culture.
N/A / Link / Jonsson , Ivar / 1999

Luleå tekniska universitet Övrigt
A book review is presented of Business Process Improvement Workbook: Documentation, Analysis, Design, and Management of Business Process Improvement by H. James Harrington, Erik K.C. Essling, and Harm Van Nimwegen.
N/A / Link / Klefsjö , Bengt / 1998

Soft Systems Methodology (SSM) has been criticized for its interpretivistic stance by, among others, Critical systems thinkers. By locating problems inherent in the techniques of SSM, this paper proposes an expanded theoretical framework, concerning measure of performance in the conceptual models. The expansion is based on the theories behind Multi-Modal Methodology and has resulted in a new model of performance indicators for the design.
N/A / Link / Bergvall-Kåreborn , Birgitta / 1996

Luleå tekniska universitet Övrigt
The question of investigation is, What can intelligent artifacts mean to a command system? By means of a theoretical synthesis of previous works, the present work starts with an epistemological discussion focused on systems thinking. With the organization in focus, an extrospective approach is taken in which a global discussion results in some implications for the organizational system design. This system is considered as a sociotechnological system; consequently, the nature of systems (i.e., complexity) and the nature of human beings (i.e., parts of the systems and who are to be served by the artifacts) are discussed. The result argues that intelligent artifacts can extend the intelligent behavior of organizations. Examples of computer system architecture and software architecture are given.
N/A / Link / Eriksson , Darek M. / 1996

Due to unsatisfactory productivity, a large company in the Swedish manufacturing industry decided to rationalize their assembly system. The intended rationalization comprised several changes with deliberate ergonomic implications. The main aim of the present study was to evaluate the impact of the rationalization on the physical work load of the operators. The work load was assessed before and after the changes using expert observations, company records and direct technical measurements. The results indicate that the intervention led to only minor changes in muscle load, body postures and movement patterns. Several of the planned initiatives were never implemented, e.g. teaching the workers multiple skills and designing work stations at which a major part of the assembly sequence could be performed. This was mainly due to a policy revision caused by changes in the market situation. In spite of the company's original intentions, the revised production system contained only minor ergonomic improvements. Thus, the realization of the ergonomic potential in a rationalization seems to depend on management culture, as well as factors outside the company.
N/A / Link / Bao , Shihan / 1996

Luleå tekniska universitet Övrigt
N/A / Link / Shahnavaz , Houshang / 1992

Luleå tekniska universitet Övrigt
Discomfort in the use of personal protective devices (PPD) has been one of the chief causes of their non-use. A field trial using industrial helmets was carried out to ascertain whether by training and repeated wearing subjects could experience a significant adaptation to discomfort. Ten subjects took part in the trial in a tropical environment by wearing helmets repeatedly (6 h a day) for one month. Subjective evaluations of discomfort were made at the end of the 1st, 3rd, 5th, 14th and 30th day. It was revealed that complaints of discomfort, viz. hotness, heaviness, bad fit, etc., decreased markedly throughout the 30 day period. Though positive responses of adaptation to discomfort seem to reach an optimum towards 30 days, it is difficult to draw any conclusions on the optimum period of adaptation for each discomfort factor. In relation to inherent discomforts that are extremely difficult to overcome without compromising the protection efficiency of a PPD, the principle of adaptation seems to be a very important facet which has to be developed for an effective PPD programme.
N/A / Link / Abeysekera , John / 1990

The adsorption mechanism of 1-vinyl-2-pyrrolidone (VP), poly(1-vinyl-2- pyrrolidone) (PVP) and azelaic acid on synthetic gamma-aluminium oxide surfaces was investigated using FT-IR, FT-Raman, UV, 1H and 13C NMR spectroscopy. (Liquid-solid state) As a first step the solvation of VP and PVP in solvents of varying polarity, specifically water, ethylene glycol (EG), chloroform and carbon tetrachloride, was studied. The IR and Raman measurements made it possible to establish the structures of the solvated molecules as well as the type of hydrogen bonding. From the UV measurements, the strength of the vinyl double bond was estimated in the different solvents. The 1H and 13C NMR spectra revealed that polar solvents attack the solutes at the carbonyl group of the pyrrolidone ring, whereas nonpolar solvents interact mainly with the vinyl group in VP and with the polymer chain in PVP. From the adsorption experiments of VP and PVP carried out in EG and water, it was concluded that VP could not be used as a model compound for PVP, because the adsorption properties of the two substances are quite different. The PVP adsorption from both, aqueous and EG solutions, was negligible. It was found that the presence of a dicarboxylic acid enhances the adsorption of PVP, due to a hydrophobic interaction between the carbon chains of the polymer and the dicarboxylic acid. This theory is supported by the experiments using dicarboxylic acids with different carbon chain lengths. However, under a critical chain length (C5) of the dicarboxylic acid, the enhancement of the PVP adsorption was diminished. The decreased PVP adsorption on the surface in case of dicarboxylic acids with short chain lengths may be explained by less hydrophobic interaction. The simultaneous adsorption of PVP and azelaic acid was studied as a function of adsorption time, pH and solvent in order to establish a more detailed surface complexation model. It was found that surface-complexation of azelaic acid in aqueous solution starts with mainly outer sphere co-ordination, driven by electrostatic forces, which is transformed to an inner sphere complex in time, forming a covalent bond between the carboxylate and the alumina surface, especially at low pH. At high pH the outer sphere complex is preferred. The pH has a strong influence on the adsorbed amount of azelaic acid and therefore on the adsorbed amount of PVP as well. With increasing pH, the electrostatic attractive forces (the driving force for the first step of the adsorption) decrease, resulting in a reduction in adsorption. The pH seemed to have no effect on the reaction between the PVP and the azelaic acid. In EG solution the complexation model is even more complex since the solvent molecules are competing for the surface sites.
N/A / Link / Száraz , Ildikó / 2000

Luleå tekniska universitet Övrigt
N/A / Link / Pousette , Kerstin / 1992

Denna avhandling presenteras i form av en monografi bestående av en teoridel och en experimentell del. Syftet med teoridelen är att ge en samlad bild av hur de termiska fenomen som förekommer inom termografi teoretiskt kan beskrivas samt hur olika faktorer påverkar resultaten vid en termografisk mätning. Målet med de experimentella mätningarna var att bestämma inträngningsdjupet för detektering av limbrist under ytskikt av olika träslag, provmetodernas upplösningsförmåga samt deras snabbhet. Det experimentella arbetet är huvudsakligen utfört med uppvärmningstermografi och lock-in-termografi. Defektdjup, defektstorlek, graden av limbrist och ytskiktets träslag har varierats. Limbommar med en termisk defektstorlek, d.v.s. kvoten av defektstorlek och defektdjup, större än 4 är detekterbara för både lock-in-termografi och uppvärmningstermografi. Under ett defektdjup på 3-4 mm ligger den bortre gränsen för detekterbarhet. Den högsta kontrasten erhålls för de största limbommarna (24 mm) under det tunnaste (0,5 mm) ytskiktet. Inga generella slutsatser beträffande ytskiktets träslag kan dras. Magra limfogar ger ungefär hälften så hög kontrast som rena limbommar. Om provningen utförs på redan svala provkroppar, är uppvärmningstermografi snabbast eftersom lock-in-termografi kräver en uppvärmningsfas för att nå ett någorlunda stationärt värmeflöde inuti provkroppen. Om provningen utförs på redan uppvärmda provkroppar, är lock-in-termografi snabbare såvida man inte kyler ned provkropparna med t.ex. kall luft, s.k. nedkylningstermografi. Den mest näraliggande tillämpningen av de studerade teknikerna ligger inom parkettindustrin.
N/A / Link / Berglind , Henrik / 2000

Luleå tekniska universitet Övrigt
Steel fibre reinforced sprayed concrete is common practice for permanent linings in underground construction. Today there is a demand on "expected technical service life" of 120 years. Thin steel fibres could be expected to discontinue carrying load fast with a decrease of fibre diameter caused by corrosion, especially in cracks. The thesis contains results from inspections on existing sprayed concrete structures and a literature review on corrosion of steel fibres in cracked concrete. To study the mechanisms ruling inititation and propagation of corrosion both field exposure tests and accelerated laboratory exposure tests with cracked steel fibre reinforced sprayed concrete have been performed. Parameters tested are type of spraying method, exposure environment, fibre length, usage of accelerators, crack width and time of exposure. A discussion on how the influence of corrosion on load bearing capacity should be considered in a service-life model is also presented.
N/A / Link / Nordström , Erik / 2000

Over the past 20 years, the use of biological air pollution control has become a popular treatment alternative for contaminated gas streams. The objective of this licentiate thesis was to investigate the feasibility of a compact rockwool biofilter to treat emissions from a restaurant, to identify an appropriate microbial population for the inoculation of the biofilter, and suitable environmental conditions for this culture. Rockwool mats with pre-set structures were shown to have a good structural stability, developed low pressure drop, did not compact, and seemed to be a appropriate habitat for microorganisms. Bacteria from different environments were enriched in batch cultures; it was found that all cultures were able to oxidize rape-seed oil. Nutrients, mainly phosphorus and nitrogen, must be added occasionally to the bacterial culture. Clogging due to high depositions of grease could be prevented by using a mechanical collector installed upstream of the biofilter. The off-gas from the fryer consisted of a complex mixture of partially oxidized hydrocarbons and the short residence times (<10 s) provided in the filter were not sufficient to achieve a significant reduction of aldehydes or fatty acids.
N/A / Link / Andersson-Chan , Anneli / 2000