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983 Uppsatser om Heat transfer - Sida 35 av 66

Upplevd trafiksäkerhet med mittbarriär

AbstractThis report intends through a case study to investigate if lightweight concrete isappropriate as main material in the outer wall of a seven storey residential building.A technical design is carried out in accordance with the definitions and requirementsfor passive houses, given by FEBY?s1 ?Demand specification for passive houses?.A literature review is also carried out for a comparison between regular bolt wall andlight weight concrete wall, with a focus on the safety of moisture.The lightweight concrete block used in the report is as a celblock produced by thecompany H+H Sweden AB.The methods used have resulted in compliance with requirements andrecommendations from authorities. Calculations of energy, noise and moisture riskassessment has been carried out.The work has resulted in the conclusion that the lightweight concrete itself is notable to isolate in the extent necessary to obtain chosen U-value of 0,1 W/m2 ° C,without getting to thick. Therefore additional insulation is needed. There are fewrelevant reference objects built with only light weight concrete.

Adaptiv temperaturreglering av bostadshus

The control of indoor temperature must be able to handle large time constants and both measureable disturbances like outdoor temperature, and non-measurable disturbances, like waste heat from appliances. Due to cheaper microcontrollers (small computers with designated tasks) with better performance, more advanced and computation-demanding methods for control can be used.In this thesis, Generalized Predictive Control (GPC) has been implemented and tested on a theoretically derived model of a house. GPC states that a model of the system is estimated in every sample, and the control is carried out simultaneously, based on predictions of the model. Disturbances like solar radiation can be estimated and used in the control as well. The control signals are determined by quadratic programming, which makes it possible to consider conditions, for example limitations on the control signals.GPC requires a number of parameters to be defined, like model order and control signal penalty, but is relatively robust for variations in them.

Utredning av Aktiv designprojektet vid RV40. Inriktning mot utveckling av objektiv kontrollmetod med avseende på framtida funktion

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Undersökning av samband mellan MCV och geotekniska parametrar. Analys utifrån fält- och laboratorieförsök på finkornig jord

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Viltbroar i Sverige. En jämförelsestudie på rörbroar av stål som alternativ till traditionella betongbroar vid uppförande av faunapassager

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Lärk eller Impregnerat ? en kvalitativt jämförande livscykelanalys av sibirisk lärk och svensk tryckimpregnerad furu

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Konstruktion av en autonom vindstation

Construction of an autonomous wind station was a project with the goal of creating a product that could collect wind data from a sensor and then transfer this data to a server wirelessly over the GSM network. The device would be powered by batteries and solar cells and function fully without requiring external power supply. This required that a small computer was constructed and programmed to store and send data at predetermined cycle times and programming of a server that received the sent data. The project also required optimization of power consumption and dimensioning of solar cells and batteries based on this. The construction of this station demanded research both for the selection of hardware and programming software. The computer was based on a microcontroller and a GSM module that sent the data over the 2G network.

Kvalitetskontroll av trafikmätningssystem ? En studie om noggrannheten hos induktiv slinga, slang, KomFram, video och radar i olika trafikmiljöer

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Metoder för långtidslagring

This study aims at examining the prospects for a policy transfer of a Swedish municipal environmental policy (that of Växjö) to the French urban commune Blois, for which an ambition of becoming a leading eco-city in France, was declared by the mayor in 2008.In the analysis, emphasis is laid on mechanisms to institutionalize the main environmental policy principles, such as political and institutional structures and processes. Other prospects for an institutionalization of a new environmental policy that are to be investigated are economic structures as well as visions of the different decision-makers concerned. Research methods used in the study are qualitative interviews, document studies and a questionnaire.The findings of the analysis show that today?s prospects for an environmental policy in Blois close to that of Växjö, are clearly limited. The limitations can partly be found in economic structures but these seem to be rather related to a lack of priority amongst actors.

Har muren fallit? En studie av policynätverk inom infrastrukturprocessen i Skåne

The creation of Region Skåne, and the transfer of the development responsibility from the national administrative country board (Länsstyrelsen) has given the state new challenges. New structures have grown between Region and State, and also between different municipalities. These can be characterized as Policy-networks, and the goal of this study is to analyze the planning process of the regional infrastructure with these theories.This is a qualitative study of the infrastructure process in Skåne, and the actors that acts within this process. It has been studied with the eyes of the theories of Governance and Policy-networks. The main method to collect material has been through interviews with different actors within the process, and very little written material has been used.

Antibiotic resistance associated with bacteria in irrigation water : a case study of irrigation ponds in Southern Sweden

The focus of this project was to characterize the occurrence of ESBL-­?producing bacteria in two irrigation water ponds in Southern Sweden. Samples were taken from two ponds nearby each other, from which analyses were made based on levels of community and individual isolates. Community samples were used for attempts for characterization of resistance patterns in irrigation water using the Omnilog PM-­?plate system. The growth of community microbiota in the presence of the following antibiotic substances was assessed; amikacin, gentamicin, kanamycin, penicillin G, ampicillin, piperacillin, trimethoprim, potassium tellurite and ciprofloxacin. Isolates were pure cultured using semi-­?selective media: LB, Rainbow Agar, mEnterococcus, 0.1 TSA and VRBD. A total of 177 isolates were isolated randomly. Each isolate was identified using the Omnilog GENIII-­?system of biochemical characterization. Further, the isolates were tested on Brilliance ESBL-­?agar for their ability to grow. Out of the total number of isolates, 30 were selected, preferably Enterobacteriaceae or Pseudomonas spp., based on their high similarity to library strain during the identification in the Omnilog-­?system. These were further characterized using Etest-­?sticks. Three selected strains were picked for further analyses using exogenous isolation for attempts to simulate horizontal gene transfer, and Omnilog PM-­?panels containing various antibiotics of interest. Selections of samples were chosen for molecular tests targeting plasmid-­?borne resistance genes CTX-­?M1, CTX-­?M2 and SHV. The method for assessing community-­?resistance patterns showed ambiguous data that was difficult to interpret; further optimization is recommended. For all tested PM-­?plates, generally greatest differences between substances were found among wells with the strongest concentration of antibiotic substance. A total of 175 isolates displayed ability to grow on ESBL-­?agar. Etests confirmed ability of isolates to resist many ?-­?lactam antibiotics and many were clinically resistant to certain substances. No plasmids were transferred during exogenous isolation. During molecular tests, a few matches were found for the CTX-­?M1 gene. Isolates analyzed with Omnilog PM-­?plates showed resistance to most compounds tested. The isolates showed greatest resistance toward penicillin G, ampicillin, amikacin, kanamycin and trimethoprim. In the study, it was established that resistance among bacteria was frequently occurring in the irrigation water, and ?-­?lactamase producing bacteria was very common. Extended studies are needed to assess the frequency-­? and occurrence of horizontal gene transfer (HGF) in this environment. Although some potential corresponding data is found, it is at this point not possible to determine whether the resistances are due to antibiotics used in veterinary medicine, human medicine or one additional reason is travel and trade. in irrigation water using the Omnilog PM-­?plate system. The growth of community microbiota in the presence of the following antibiotic substances was assessed; amikacin, gentamicin, kanamycin, penicillin G, ampicillin, piperacillin, trimethoprim, potassium tellurite and ciprofloxacin. Isolates were pure cultured using semi-­?selective media: LB, Rainbow Agar, mEnterococcus, 0.1 TSA and VRBD. A total of 177 isolates were isolated randomly. Each isolate was identified using the Omnilog GENIII-­?system of biochemical characterization. Further, the isolates were tested on Brilliance ESBL-­?agar for their ability to grow. Out of the total number of isolates, 30 were selected, preferably Enterobacteriaceae or Pseudomonas spp., based on their high similarity to library strain during the identification in the Omnilog-­?system. These were further characterized using Etest-­?sticks. Three selected strains were picked for further analyses using exogenous isolation for attempts to simulate horizontal gene transfer, and Omnilog PM-­?panels containing various antibiotics of interest. Selections of samples were chosen for molecular tests targeting plasmid-­?borne resistance genes CTX-­?M1, CTX-­?M2 and SHV. The method for assessing community-­?resistance patterns showed ambiguous data that was difficult to interpret; further optimization is recommended. For all tested PM-­?plates, generally greatest differences between substances were found among wells with the strongest concentration of antibiotic substance. A total of 175 isolates displayed ability to grow on ESBL-­?agar. Etests confirmed ability of isolates to resist many ?-­?lactam antibiotics and many were clinically resistant to certain substances. No plasmids were transferred during exogenous isolation. During molecular tests, a few matches were found for the CTX-­?M1 gene. Isolates analyzed with Omnilog PM-­?plates showed resistance to most compounds tested. The isolates showed greatest resistance toward penicillin G, ampicillin, amikacin, kanamycin and trimethoprim. In the study, it was established that resistance among bacteria was frequently occurring in the irrigation water, and ?-­?lactamase producing bacteria was very common. Extended studies are needed to assess the frequency-­? and occurrence of horizontal gene transfer (HGF) in this environment. Although some potential corresponding data is found, it is at this point not possible to determine whether the resistances are due to antibiotics used in veterinary medicine, human medicine or one additional reason is travel and trade..

Framtagning av ett nytt recept för clear-coat batter av pommes frites : En teknisk och sensorisk utvärdering

The requirements of good quality and appetizing fast food increases continuously as a consequence of a community where food is always available. The crispiness of French fries is an issue that must be considered in this context, since it tends to decrease and give the fries a soft surface not appreciated by the consumer. To prolong the crispiness, the fries can be coated by a batter, a mix of starches. The batters used often consists of modified starches, e.g. cross-linked, acetylated and dextrinizated to increase and prolong crispiness, flour to stabilize the batter and sodium bicarbonate to make the batter ?rise?.The cross-linked starch keeps the granules in a swelled state and prevents them from breaking when exposed to heat or processing: therefore, it delays the gelatinization and decreases the stickiness of the batter.

DATORSTÖD FÖR ARBETE - KONSEKVENSER FÖR VAL AV AFFÄRSSYSTEM En studie av en service- och supportavdelning

This report is focusing on problems with introducing standard enterprise resource planning systems (ERP) in businesses. A study has been carried out on a service and support department at a Swedish heat metering company, SVM North Node. The study aims to help the company become a better customer in choice and customization of a new ERP system. We make a description of the department studied and the work carried out there, on the basis of learning, knowledge and cooperation. As a final point we present some ideas on how computer systems could support their work, hoping that this will result in them making adequate demands on a new ERP system.

Utvecklingens dimensioner: utifrån ledarskapsutvecklarnas perspektiv

The market for management training programs is growing and the supply of the service is increasing and getting further diversified. A consequence is a market with a wide variety of definitions of the very concept of development, and subsequently a wide variety of practices and methods to achieve development. The individuals that are subject to these programs seldom know what they are purchasing, or what to expect. When assuming a transfer of the developers view on development to the subject, a need for a greater understanding of the concept arises. The purpose of this thesis is to understand what views on development do exist among management trainers and map underlying dimensions of the views to increase the understanding of the concept of development.

Interaktionsloggning i Scania Interactor

Scania provides a fleet management system for hauliers who want to control their fleets in anefficient way. The system includes an onboard computer with touch screen called ScaniaInteractor where the driver can access GPS navigation, order support, message service and otherfunctionalities. The purpose of this thesis is to develop a concept for logging the user interactionon the Interactor and analyze the result which enables further development and optimization ofthe interface.A demonstration application is designed, implemented and tested for the purpose of showing thepossibilities and difficulties with logging of interaction. The result shows that logging is quiteeasy to implement and that the amount of produced data is small and therefore not expensive totransfer via GPRS to a central server where searching and analysis can be done. On the otherhand, the biggest challenge lies in the analysis and interpretation of the logged data and to applyit to the development of the interface.

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