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With new technology come new opportunities? : A study of Swedish TV production companiesSundnäs, Hannah January 2011 (has links)
This thesis are investigating production companies in Sweden and how they are working with new technology, such as web TV, mobile TV but also how they handle their business models and if they are working with other financial forms to reach revenue. All the interviewed companies said that they worked with their business models but not to the extent that they should, and this is a side effect to the risk that it might involve. They do work with the new opportunities that are given to them but are afraid to take too big of a risk. The market seems to be on the upswing and they are getting a larger marginal to the distributors and are able to take bigger risk and develop new ways to reach out with their productions.
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Water transmission line leak detection using extended kalman filteringLesyshen, Ryan M 04 April 2005
A model-based estimation process is implemented in simulation of a water transmission line for the purpose of leak detection. The objective of this thesis is aimed at determining, through simulation results, the effectiveness of the Extended Kalman Filter for leak detection.
Water distribution systems often contain large amounts of unknown losses. The range in magnitude of losses varies from 10 to over 50 percent of the total volume of water pumped. The result is a loss of product, including water and the chemicals used to treat it, environmental damage, demand shortfalls, increased energy usage and unneeded pump capacity expansions. It is clear that more control efforts need to be implemented on these systems to reduce losses and increase energy efficiencies. The problems of demand shortfalls, resulting from lost product, are worsened by the limited availability of water resources and a growing population and economy. The repair of leakage zones as they occur is not a simple problem since the vast majority of leaks, not considered to be major faults, go undetected.
The leak detection process described in the work of this thesis is model based. A transient model of a transmission line is developed using the Method of Characteristics. This method provides the most accurate results of all finite-difference solutions to the two partial differential equations of continuity and momentum that describe pipe flow. Simulations are run with leakage within the system and small transients are added as random perturbations in the upstream reservoir head. The head measurements at the two pipe extremes are used as inputs into the filter estimation process.
The Extended Kalman Filter is used for state estimation of leakage within the transmission line. The filter model places two artificial leakage states within the system. The estimates of these fictitious leakage states are then used to locate the actual position and magnitude of leakage within the transmission line. This method is capable of locating one leak within the line.
The results of the Extended Kalman Filter (EKF) process show that it is capable of locating the position and magnitude of small leaks within the line. It was concluded that the EKF could be used for leak detection, but field tests need to be done to better quantify the ability of these methods. It is recommended that a multiple filtering method be implemented that may be able to locate the occurrence of multiple leakage.
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Breast, cervical and colorectal cancer survival rates for northern Saskatchewan residents and First NationsAlvi, Riaz Anwar 06 October 2008
This descriptive study was done 1) to explore and describe the proportional distribution of breast, cervical and colorectal cancers by stage (a proxy measure of availability, access, and utilization of secondary prevention strategies) in northern Saskatchewan First Nations and non-First Nations in comparison to southern Saskatchewan First Nations and non-First Nations; 2) to assess the impact of stage and age on the survival patterns for these cancers in northerners and First Nations whose survival patterns have been shown by previous research to be equal or poorer in comparison to southerners. Univariate and multivariate survival analyses were carried out to ascertain the impact of the different proportions of stage for each study group on survival. Stage at time of diagnosis is a proxy assessment of secondary prevention services, which include formal screening programs.<p>
Data for this study was obtained from the Saskatchewan Cancer Registry, which has been maintaining cancer data since 1932. Cancer stage at time of diagnosis information is complete in the registry for different years for each cancer site. Hence data for breast cancer was for the years 1970 to 1995; cervical cancer data for the years 1980 to 1995; colorectal cancer data for the years 1990 to 1995. <p>
The proportion of cancer cases for each site by TNM stage and age were compared among the four study groups. First Nation and northern populations were found to have a larger proportion of diagnoses at a later stage in comparison to the southern non-First Nation group. <p>
Using Cox's proportional hazards model, both stage and age at time of diagnosis were found to be significant predictors of survival for all study groups. Age and stage adjusted relative risks were calculated and found to be significant in comparison to the southern non-First Nation group for cancer of the breast (RR =1.81 P=0.013). For cervical cancer the relative risk of dying of cervical cancer for southern First Nations in comparison to southern non-First Nations was found to be 1.38 but this was not statistically significant (p = 0.097). For colorectal cancer, the relative risk of dying of colorectal cancer was found to be better for northern First Nations in comparison to southern non-First Nations (RR = 0.59), however this was not statistically significant (p = 0.45).<p>
This study showed that despite adjusting for stage and age at time of diagnosis, there were still some unexplained differences in the survival pattern of northern First Nations, northern non-First Nations and southern First Nations in comparison to southern non-First Nations. Hypotheses as to what these unexplained differences are have been offered. These include differences in socio-economic status as well as availability, accessibility, attitudes towards and knowledge of secondary prevention strategies. Further study into these unexplained differences should be carried out.
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Middle Cypriot White Painted Ware: A Study of Pottery Production and Distribution in Middle Bronze Age CyprusGagne, Laura 21 August 2012 (has links)
White Painted Ware, the most identifiable of pottery types of the Middle Bronze Age on Cyprus, has been studied by scholars either with the view to creating chronological typologies or to tracing trade routes. Little attention has been paid to the technology and social organization of production of this pottery. This thesis is concerned with the potters as much as with the pottery. The production sequence is examined from clay selection through to decoration of the vessels. An attempt is made to isolate production centres with unique methods of vessel construction as well as preferences for certain shapes and decorative schemes. Using petrographic analysis, different fabrics are isolated within the ware, and these are in turn related to the groups of vessels created based on style. Similar fabrics are used in multiple sites and most sites were found to have used multiple fabrics to create pottery that is considered to be part of the White Painted ware group. Beneath the major differences in styles between sites are several minor variations in construction method and decoration that are more likely to represent choices made by individual potters or small groups of potters working together. Based on vessel shape and decoration, seven distinct production centres appear to have been manufacturing White Painted ware on Cyprus over the course of the Middle Bronze Age. These were not operating simultaneously, but appear to have been active at the time that their regions were most prosperous, linking the production and use of White Painted ware with political and economic power.
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Middle Cypriot White Painted Ware: A Study of Pottery Production and Distribution in Middle Bronze Age CyprusGagne, Laura 21 August 2012 (has links)
White Painted Ware, the most identifiable of pottery types of the Middle Bronze Age on Cyprus, has been studied by scholars either with the view to creating chronological typologies or to tracing trade routes. Little attention has been paid to the technology and social organization of production of this pottery. This thesis is concerned with the potters as much as with the pottery. The production sequence is examined from clay selection through to decoration of the vessels. An attempt is made to isolate production centres with unique methods of vessel construction as well as preferences for certain shapes and decorative schemes. Using petrographic analysis, different fabrics are isolated within the ware, and these are in turn related to the groups of vessels created based on style. Similar fabrics are used in multiple sites and most sites were found to have used multiple fabrics to create pottery that is considered to be part of the White Painted ware group. Beneath the major differences in styles between sites are several minor variations in construction method and decoration that are more likely to represent choices made by individual potters or small groups of potters working together. Based on vessel shape and decoration, seven distinct production centres appear to have been manufacturing White Painted ware on Cyprus over the course of the Middle Bronze Age. These were not operating simultaneously, but appear to have been active at the time that their regions were most prosperous, linking the production and use of White Painted ware with political and economic power.
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Production Model and Consumer Preferences for Texas PecansChammoun, Christopher James 2012 August 1900 (has links)
High prices in any industry, agricultural especially, tend to spur new investment opportunities. Recent prices for pecans have been high relative to their historical pattern, suggesting investment opportunities for pecans. Prior to any investment, the investor needs to know what products consumers are demanding and how profitable it is to grow those products. This study assessed Texas consumers' preferences for pecan products and the profitability of growing pecans in the central Texas region.
A choice experiment was conducted amongst Texas consumers to reveal consumers' preferences and determine their willingness-to-pay for the attributes comprising pecan products. A stochastic production model was formulated to determine the profitability of three different types of pecan orchards: a native orchard with no irrigation, an improved varieties orchard with irrigation, and an improved varieties orchard without irrigation.
Results from the choice experiment indicated that consumers preferred large size pecans, native variety pecans, pecan halves, United States-grown pecans, and Texas-grown pecans. The choice experiment also found that consumers were heterogeneous in their preferences for all attributes except pecan variety and U.S. origin. Results from the stochastic production model indicated that the most profitable pecan orchard in central Texas was the irrigated improved orchard.
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Using ultrasound to investigate relaxation and resonance phenomena in wheat flour doughFan, Yuanzhong 14 September 2007 (has links)
This thesis is based on observations of the physical properties of wheat flour dough using ultrasonic measurements. Three frequency ranges were used in the study, low
frequencies (near 40 kHz), intermediate frequencies (1 to 5 MHz, where bubble
resonance effects are apparent), and high frequencies (near 20 MHz). Doughs mixed
under different head space air pressures, from vacuum to atmospheric pressure, as well as under nitrogen, were studied at low frequency to investigate their relaxation behavior. Subsamples from ambient dough and vacuum dough displayed differences in the
dependence of velocity and attenuation on time after compression, but no post mixing
relaxation effect was apparent. A critical headspace pressure of approximately 0.16
atmospheres determined whether vacuum-like or ambient-like relaxation was observed.
A peak in attenuation and changes in ultrasonic velocity were observed around the bubble resonance frequency, and these ultrasonic parameters changed substantially as a function of time. A bubble resonance model was used to interpret the results around the bubble resonance frequency, and bubble size distributions were estimated for ambient and vacuum dough from the ultrasonic data. For the high frequency range, a molecular relaxation model was used to interpret the results. Different fast relaxation times were observed for ambient dough (5 ns) and vacuum dough (1 ns). This relaxation time may be associated with conformational rearrangements in glutenin inside the dough matrix. These experiments have enabled dough relaxation to be probed over a very wide range of time scales (from ns to hours), and will lead to a better understanding of the role of dough matrix and gas cell effects on the physical properties of wheat flour doughs. / October 2007
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Method for determining phasedistribution and characteristic lenghts in cBN-composite materials.Gunneriusson, Olof January 2013 (has links)
An image analysis method has been developed for Sandvik to determine phasecompositions and characteristic length of the binding phase in cubic Boron Nitride(cBN)-composites with low contents of cBN (35-75%).The method consists of taking pictures with a Scanning Electron Microscope,gathering elemental data with X-ray Diffraction (XRD) as well as Energy-dispersiveX-ray Spectroscopy (EDS) and finally using a Matlab program developed for this workto calculate phase compositions and statistical data from the characteristic length ofthe binding phase.Using these methods four different phases were identified in the samples: Blackparticles, most likely made of cBN. A dark gray phase around the black particles, thatconsists of Al-compounds. A light grey binding phase, consisting of TiN or Ti(C,N).Finally there were small traces of white particles which were identified as a product ofabrasive action on cermet milling bodies added during the milling.Mean value, standard deviation and median of the characteristic length of the bindingphase was calculated. For all samples the median value was consistent, sometimeseven being identical for the analyzed sites. This indicates that the binding phase wasevenly distributed across almost all samples.
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Cost Reduction Opportunities in Local Distribution Grids with Demand ResponseNissen, Gustaf January 2010 (has links)
The development of future smart electricity grids is driven by efficiency and climate targets and economic benefit for producers, retailers and customers on the deregulated electricity market. Since most investments will be made by grid owners acting as regulated monopolies, it is unclear how they will get return on their investments. Can demand response programs create cost reductions for the grid owner that help motivate the investment in smart grids? Two cases of cost reduction opportunities are evaluated assuming that peak loads are reduced by a demand response program: optimization of cable dimensions for lower peak loads when building new grids, and avoided investments in reinforced capacity in the existing grid. Potential cost reductions are estimated for the two example cases, using financial and technical data for Fortum's local distribution grid in Stockholm. The result shows that reducing the capacity in the cables by 70-80 % only brings down investment costs by 3-4 %, since the common expense for excavation outweighs the incremental cost of cables. Over-capacity means increased redundancy and flexibility to increase load in the future, which are valuable features for a grid owner.Regarding investments in the existing grid, a substation that needs replacement because of overload is analyzed. Assuming a continued trend of steadily increasing load, a 34 % peak load reduction would delay the investment 20 years, which is in turn worth 900,000 SEK in 2010 prices.
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Desinfektion av kommunalt dricksvatten vid långa distributionsvägar och råvatten från sjön VätternKarlsson, Jonny January 2011 (has links)
Rapporten är ett resultat av en undersökning som initierades av att man i Motala kommun ville sluta använda sig av kloramin för dricksvattendesinfektionen vid sitt ytvattenverk i Råssnäs. Man ville utesluta ammoniak vid dricksvattenframställningen och övergå till att enbart desinficera med hypoklorit. Råssnäs tar sitt råvatten från Vättern och det färdiga vattnet distribueras sedan upp till 30 km från verket. I samband med att man ville göra förändringen var man intresserad av att veta hur man utför desinfektion vid andra vattenverk med liknande förutsättningar d.v.s. råvatten från Vättern och långa distributionsvägar. Med utgångspunkt från dessa förutsättningar valdes kommunerna Askersund och Jönköping samt kommunalförbundet Skaraborgsvatten ut för att tillfrågas om hur man där arbetar med sin dricksvattendesinfektion. Undersökningen begränsas av att endast tre kommunala aktörer deltog men dessa bedömdes vara de som bäst uppfyllde de angivna förutsättningarna. Från de avgivna svaren kan man dra slutsatsen att båda metoderna, desinfektion med kloramin eller enbart hypoklorit, används och tycks fungera bra. Problem uppstår i första hand under den varma delen av året då vattnet i ledningarna värms upp vilket kan främja den mikrobiella tillväxten. Åtgärden blir i sådana fall i första hand att utföra stödklorering ute på nätet. Desinfektions metoderna mella kommunerna/kommunalförbundet varierar. I Askersund doseras endast hypoklorit och man har inga erfarenheter från andra metoder. I Jönköping har man i sitt största verk nyligen övergått från kloramin till enbart hypoklorit och fick i samband med detta under den första tiden många klagomål på dålig smak och lukt hos dricksvattnet. Problemen avtog efterhand och efter ett halvår hade klagomålen upphört. Man tror att störningarna uppstod då biofilmen i ledningsnätet regerade på den kraftigare kloreringen för att därefter gradvis anpassa sig till nya förhållanden. Skaraborgsvatten använder sig av både förklorering med hypoklorit samt efterklorering med klor och ammoniak. Halva klormängden bildar då kloramin med ammoniaken medan den andra halvan reagerar med en momentan desinficerande effekt. De erhållna svaren visar också att UV-ljus används, eller planeras att användas, och byggs ut inom verksamheten hos alla de tre tillfrågade dricksvattenproducenterna. Rådet till Motala blir att man provar att avsluta ammoniakdoseringen och övergår till enbart hypoklorit. Dock bör man under en tid efter förändringen, för att undvika att störningar uppstår, utöka kontrollen av vattnet genom extra provtagning på lämpliga platser ute i ledningsnätet och då framförallt efter sommaren då vattnet är som varmast. Det är även lämpligt att förbereda för att kunna stödklorera, förslagsvis ute vid tryckstegringsstaioner, samt att ytterligare bygga ut användningen av UV-ljus ute på nätet vid t.ex. tryckstegringar och reservoarer.
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