Lic.-avh. Linköping : Univ., 2004.

Diss. Karlskrona : Blekinge tekniska högskola, 2005.

Licentiatavhandling (sammanfattning) Stockholm : Kungliga Tekniska högskolan, 2009. / Härtill 3 uppsatser.

Diss. Linköping : Linköpings universitet, 2010.

Syftet med mitt examensarbete var att undersöka vilka faktorer som gör teknisk kommunikation tillgänglig och lättförståelig. Det skulle leda fram till en läsvärd lathund för användare av ett nytt CMS-system.   Arbetet har genomförts i samarbete med Telia, som är inne i ett förändringsarbete gällande sina informationssystem. De ska införa ett nytt så kallat PIM-system (Product Information Management), som ska innefatta ovan nämnda CMS-system och kommer innebära ett förändrat arbetssätt och nya arbetsuppgifter för min berörda målgrupp.   För att lösa problemet har jag tagit hjälp av en fokusgrupp och gjort en webbenkät. Jag har ställt mig frågor om vad teknisk kommunikation kan bidra med vid framtagning av ett instruerande material, samt i vilka syften användarna kan tänkas läsa den typen av material.   Med hjälp av teorier och ovanstående metoder producerade jag ett förslag på hur lathunden kan se ut. Jag testade också förslaget på målgruppen för att få deras åsikter, i syfte att förbättra slutresultatet. / The purpose of this thesis was to explore what factors make technical communication accessible and easily understandable. The thesis would result in a readable cheat sheet, made for users of a new CMS system.   The work was made in collaboration with Telia. The company is looking over its information systems to implement a so-called PIM system (Product Information Management) in the near future. The CMS system will be a part of that system and the change of process will also lead to changes in the work procedures and tasks of the personnel at Telia.   To solve this problem, I made an interview with a focus group and a questionnaire amongst the target group. I asked myself what technical communication could contribute to in the making of instructional material and also in what purposes you read that type of material.   With these methods, and of course the theory of this thesis, in mind I produced a prototype of what the cheat sheet would look like. I also tested the cheat sheet at my target group, to get their opinion on the material to make the appropriate improvements.

The Yankee cylinder is used in most of Metso Paper's machines. It is used in the drying and creping process. Since the outcome of these processes largely affect the paper's final quality it is important that the Yankee cylinder behaves in a controlled fashion. One important parameter affecting the behaviour of the Yankee cylinder is its surface temperature. The objective of this thesis was to search for and evaluate methods for measuring the surface temperature of a Yankee cylinder during operation. Metso Paper is looking for a method having an accuracy of ΔT = 1°C, a response time of t<10 ms, and being portable. Three different instruments were tested during the thesis: Thermophone, a contact measurement device currently used by Metso Paper. RAYNGER MX4, a pyrometer from Raytek. FLIR P640, a thermographic camera with a 640x480 focal plane array from FLIR. The instruments were tested by performing measurements on Metso Paper's pilot machine in Karlstad during operation. The measurements revealed drawbacks for all three instruments. The biggest drawbacks of the Thermophone was its response time, t~5 min, and its dependence on the frictional heating of the teflon cup. The frictional heating causes the measured temperature to increase even after 15 min making it hard to know when to stop the measurement. How much the frictional heating affects the measured temperature was difficult to analyse, making it a suggestion for future studies. The biggest drawback of the pyrometer and the thermographic camera is the measurement error due to emissivity errors. Since the Yankee cylinder have a varying surface finish the emissivity varies a lot along the surface introducing temperature errors as large as ΔT=30°C. Two methods that claim to be emissivity independent were investigated; double-band and gold cup pyrometers. Double-band pyrometers require the target to be a grey body and for it to have large temperatures, T>300°C, making this method unsuitable for measuring the surface temperature of the Yankee cylinder. Gold cup pyrometers require the gold hemisphere to have a reflectance of ρ=1. Because of the environment surrounding the Yankee cylinder it would be difficult keeping the gold hemisphere as clean as required making this method unsuitable as well.

<p>The overall aim of this thesis was to discuss kinematics and muscle function changes due to foot and ankle injury or deformity. The first study aims to characterize gait patterns of subjects with a common lower limb injury, ankle fractures. Using three-dimensional movement analysis with a modified multi-segment foot model, the inter-segment foot kinematics was determined during gait in 18 subjects one year after surgically treated ankle fractures. Gait data were compared to an age- and gender-matched control group and the correlations between functional ankle score and gait parameters were determined. It was observed that even with fairly good clinical results, restricted range of motion at and around the injured area, and less adducted forefoot were found in the injured limb. The second study aims to quantify the effect of subtalar inversion/eversion on the dynamic function of the main ankle dorsi/plantarflexors: gastrocnemius, soleus and tibialis anterior. Induced acceleration analysis was used to compute muscle-induced joint angular and body center of mass accelerations. A three-dimensional subject specific linkage model was configured by gait data and driven by 1 Newton of individual muscle force. The excessive subtalar inversion or eversion was modified by offsetting up to ±20˚ from the normal subtalar angle while other configurations remain unaltered. We confirmed that in the normal gait, muscles generally acted as their anatomical definitions and muscles can create motion in joints, even not spanned by the muscles. The plantarflexors play important roles in body support and forward progression. Excessive subtalar eversion had negative effect on ankle plantarflexion, which may induce a less plantarflexed ankle, less extended knee and more flexed hip after initial contact. This thesis focused on gait kinematics and muscle functions in the foot and ankle area employing both experimental gait and computational simulations. The findings can be regarded as references for evaluating of future patients and for dynamic muscle functions during gait.</p>

<p>Converging cylindrical shock waves have been studied experimentally. Numericalcalculations based on the Euler equations and analytical comparisons basedon the approximate theory of geometrical shock dynamics have been made tocomplement the study.Shock waves with circular or polygonal shock front shapes have been createdand focused in a shock tube. With initial Mach numbers ranging from 2 to4, the shock fronts accelerate as they converge. The shocked gas at the centreof convergence attains temperatures high enough to emit radiation which isvisible to the human eye. The strength and duration of the light pulse due toshock implosion depends on the medium. In this study, shock waves convergingin air and argon have been studied. In the latter case, the implosion lightpulse has a duration of roughly 10 μs. This enables non-intrusive spectrometricmeasurements on the gas conditions.Circular shock waves are very sensitive to disturbances which deform theshock front, decreasing repeatability. Shocks consisting of plane sides makingup a symmetrical polygon have a more stable behaviour during focusing,which provides less run-to-run variance in light strength. The radiation fromthe gas at the implosion centre has been studied photometrically and spectrometrically.Polygonal shocks were used to provide better repeatability. Thefull visible spectrum of the light pulse created by a shock wave in argon hasbeen recorded, showing the gas behaving as a blackbody radiator with apparenttemperatures up to 6000 K. This value is interpreted as a modest estimation ofthe temperatures actually achieved at the centre as the light has been collectedfrom an area larger than the bright gas core.As apparent from experimental data real gas effects must be taken intoconsideration for calculations at the implosion focal point. Ideal gas numericaland analytical solutions show temperatures and pressures approaching infinity,which is clearly not physical. Real gas effects due to ionisation of theargon atoms have been considered in the numerical work and its effect on thetemperature has been calculated.The propagation of circular and polygonal have also been experimentallystudied and compared to the self-similar theory and geometrical shock dynamics,showing good agreement.</p>

Vid upphandling inom offentlig sektor eller större företag kan användandet av standarder vara ett viktigt redskap för att säkerställa att en produkt eller tjänst uppfyller de krav som verksamheten ställer när det gäller exempelvis kvalitet, kostnader och effekter på miljön. Stigande priser på energi och en ökad insikt om samhällets negativa inverkan på miljön gör att energieffektiviseringar blivit ett viktigt inslag i de allra flesta verksamheter och här kan användandet av standarder spela en viktig roll.Syftet med det här examensarbetet är att utreda hur isolering av varma och kalla rör samt ventilationskanaler kan dimensioneras optimalt så att energiförluster från dessa minimeras. Hur olika faktorer och förutsättningar påverkar vad som är en optimerad isolering måste därmed även att utredas så att konsekvenser av olika val kan kartläggas.Målet är att ta fram ett underlag som kan fungera som hjälpmedel då en ny standard för dimensionering av teknisk isolering skall tas fram av Landstingsfastigheter i Värmland. Underlaget kommer att utgöras av en beräkningsmodell som skall kunna ge tillförlitliga uppgifter om hur olika yttre faktorer samt val av isoleringsmaterial dels kan påverka vilken den nödvändiga isoleringstjockleken blir och dels visa de ekonomiska konsekvenserna. En livscykelkostnadsanalys gjordes därför för olika dimensioneringsalternativ.Arbetet resulterade i en beräkningsmodell som kan användas för att beräkna olika isoleringstjocklekar för olika typer av fall. Grundprincipen för beräkningsmodellen är att det skall gå att undersöka vilken isoleringstjocklek som behövs då en bestämd energiförlust eller temperatur på isoleringens yta skall uppnås. Isoleringen till varma rör dimensioneras för en reducerad energiförlust medan isolering till kalla rör och ventilationskanaler dimensioneras för en önskad temperatur på isoleringens yta. Livscykelkostnadsanalysen visade att dimensioneringen bör göras för en så liten energiförlust som möjligt.Ett antal olika fall undersöktes med hjälp av beräkningsmodellen. Beräkningarna visade att val av material och ytskikt kan få en betydande inverkan på hur isoleringen måste dimensioneras för att de mål som sätts för den skall uppnås. Att välja en produkt med något lägre värmeledningsförmåga kunde exempelvis minska isoleringsbehovet med nästan 20 % på större rördimensioner. Huruvida isoleringen prioriteras i ett tidigt skede av en projektering eller ej kan också få stora konsekvenser för hur stor ett systems energiförlust blir eftersom en avgörande faktor ofta är om isoleringen får plats i utrymmet. Dimensionering av isolering för kalla system som syftar till att motverka kondensutfällning på isoleringens yta visade sig innebära förhållandevis stora energiförluster. Detta tyder på att isolering av kalla installationer istället borde dimensioneras mot energiförluster.

This thesis concerns the analytical and numerical analysis of the water vapour condensation from the multicomponent mixture of condensable and noncondensable gases in the area of the nuclear reactor thermal-hydraulic safety. Following an extensive literature review in this field three aspects of the condensation phenomenon have been taken into consideration: a surface condensation, a liquid condensate interaction with gaseous mixtures and a spontaneous condensation in supersaturated mixtures. In all these cases condensation heat and mass transfer rates are significantly dependent on the local mixture intensive parameters like for example the noncondensable species concentration. In order to analyze the multicomponent mixture distribution in the above-mentioned conditions, appropriate simplified physical and mathematical models have been formulated. Two mixture compositions have been taken into account: a binary mixture of water vapour with heavy noncondensable gas and a ternary mixture with two noncondensable gases with different molecular weights. For the binary mixture a special attention has been focused on the heavy gas accumulation in the near-interface region and the influence of liquid film instabilities on the interface heat and mass transfer phenomena. For the ternary mixture of gases a special attention has been paid to the influence of the light gas and induced buoyancy forces on the condensation heat and mass transfer processes. Both analytical and numerical methods have been used in order to find solutions to these problems. The analytical part has been performed applying the boundary layer approximation and the similarity method to the system of film and mixture conservation equations. The numerical analysis has been performed with the in-house developed code and commercial CFD software. Performing analytical and CFD calculations it has been found that most important processes which govern the multicomponent gas distribution and condensation heat transfer degradation are directly related to the interaction between interface mass balances and buoyancy forces. It has been observed that if the influence of the liquid film instabilities is taken into consideration the heat transfer enhancement due to the presence of different types of waves is directly related to the internal film hydrodynamics and shows up in the mixture-side heat transfer coefficient. The model developed for the dispersed phase growth shows that degradation of the condensation heat transfer rate, which is a consequence of degradation of the convective mass flux, should be taken into account for highly supersaturated gaseous mixtures and can be captured by combination with the mechanistic CFD surface condensation model. Keywords: condensation, noncondensable gases, CFD simulation, boundary-layer approximation, binary and ternary mixtures / <p>QC 20100623</p>