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404 Uppsatser om Virtous cycle - Sida 5 av 27

Förbehandlingstekniker och LCA för rötning av organiskt avfall : Modellkonstruktion och Utvärdering med ORWARE

The goal of this master thesis project was to develop computer models of some plausiblepretreatment techniques and to assess the potential benefits/costs of using pretreatment andanaerobic digestion for waste management of organic waste from a system perspective. Forthis purpose a computer program called ORWARE has been used. ORWARE (organic wasteresearch) is a program for making life cycle assessments of waste management. As the mainpart of the project work the ORWARE system has been provided with three new models ofpretreatment techniques. The additions consist of: One model of pretreatment with ultrasound,one model of thermal hydrolysis and one model of a screw press.

Solel och solvärme ur LCC-perspektiv för ett passiv-flerbostadshus

This master?s degree project concerns the combination of a multi dwelling passive house with solar energy for the generation of electricity and domestic hot water (DHW). Different alternatives with either solar thermal systems or photovoltaic (PV) systems are compared with two reference alternatives producing DHW from electricity or district heating. The economical comparison uses a life cycle cost (LCC) perspective based on the present value of expenditures for investment, energy and annual operating and maintenance.The energy yields from the solar energy systems were calculated by hand and with simulation software. Calculation and dimensioning of PV systems were carried out with a software called PVSYST.

Regressionsmodellering av dynamiska råemissioner från statiska mätningar

By using steady-state measurements for predicting emissions under a dynamic drive cycle wouldsave a lot of time and money for the exhaust aftertreatment specialists at Volvo cars. The idea forthis thesis has been to investigate if statistical regression models can be used with good accuracy.Questions included are for example if common operating variables such as engine speed, air-fuelratio etc. is sufficient to predict engine-out emissions over the engine operating range with goodaccuracy. Focus was set on the modelling of warm engine, but also the more complex engineheat-up phase was investigated since it is a great contributor to total emissions. While NOxcouldnot be measured because of malfunctioning measurement equipment, only HC, CO andtemperature at inlet of first catalytic converter has been modelled.

Jämförelse mellan subjektiv och objektiv bedömning av hälta hos häst på böjt spår.

The female dog has a unique reproductive endocrinology, with high levels of progesterone throughout the 70-day long luteal phase. In this project, markers of glucose metabolism were studied and compared from the aspects of breed group and time in oestral cycle. The parameters studied were: glucose, insulin, progesterone, fructosamine and the newly introduced analysis of HbA1c. Hba1c was also further evaluated and discussed as a diagnostic tool in canine medicine.No differences in terms of glucose markers were found between a group of purebreed dogs of various breeds compared to a group of dogs with high risk of dioestrus diabetes, namely the Norwegian and Swedish elkhounds.No differences were found between the two sample occasions, anoestrus and dioestrus, concluding that there is no need for relating test results to the time of the oestrous cycle in middle-aged intact female dogs.There were statistically significant higher values of all glucose markers in diabetic dogs than in non-diabetic dogs. When it came to HbA1c, however, there was a larger overlap between the two groups, compared to fructosamine.

Slithållfastheten för dentin och cement i förhållande till emalj in vivo hos häst

The female dog has a unique reproductive endocrinology, with high levels of progesterone throughout the 70-day long luteal phase. In this project, markers of glucose metabolism were studied and compared from the aspects of breed group and time in oestral cycle. The parameters studied were: glucose, insulin, progesterone, fructosamine and the newly introduced analysis of HbA1c. Hba1c was also further evaluated and discussed as a diagnostic tool in canine medicine.No differences in terms of glucose markers were found between a group of purebreed dogs of various breeds compared to a group of dogs with high risk of dioestrus diabetes, namely the Norwegian and Swedish elkhounds.No differences were found between the two sample occasions, anoestrus and dioestrus, concluding that there is no need for relating test results to the time of the oestrous cycle in middle-aged intact female dogs.There were statistically significant higher values of all glucose markers in diabetic dogs than in non-diabetic dogs. When it came to HbA1c, however, there was a larger overlap between the two groups, compared to fructosamine.

Skadliga nollflödespunkter i Fortum Värmes fjärrvärmenät i Stockholm : En analys av dess förekomst och effekter

When several production units provide a district heating network, water is pumped from different directions. When the flows from the plants finally meet in the network, the water can be completely still. These places are called zero flow zones. In district heating networks with several plants, which also have different supply temperatures, large and frequent temperature fluctuations can occur when the zero flow zones move. This may cause wear on the pipes, a phenomenon called low cycle fatigue.For this reason it is important to examine where and when zero flow zones that cause temperature changes occur.

Total Cost of Ownership -Revealing the true cost of owning and operating equipment

Abstract Title: Total Cost of Ownership ? Revealing the true cost of owning and operating equipment. Authors: Anna Bladh Anna Ström Tutors: Michaela Boye, Parts and Service, PTD, Alfa Laval Göran Berg, Parts and Service, PTD, Alfa LavalCharlotta Johnsson, Department of Automatic Control, LTH, Lund UniversityBertil I. Nilsson, Department of Industrial Management and Logistics, LTH, Lund UniversityCarl-Henric Nilsson, Department of Business Administration, Lund University Core issue: ?Which costs should be included in a general Total Cost of Ownership model regarding centrifuges, and what input variables are needed in order to calculate those costs in a user-friendly way and with a maintained level of accuracy?? Purpose: The theoretical purpose of the thesis is to identify the cost items that have the greatest impact on a TCO calculation for a centrifuge.

Livscykelbaserad miljövärdering av en ny kontorsbyggnad : En jämförande studie mellan två analysmetoder

This Master?s Thesis aims to illustrate in what ways the two Swedish environmental assessment tools, the Environmental Load Profile and EcoEffect differ and if performed valuations gives different results and environmental goals.The built urban environment causes about half the environmental loading in Sweden. The society?s ambition towards sustainable development has resulted in demands reducing the environmental load. One way to accomplish this change is with the assistance of tools for environmental assessment of the built environment.

Från Skiss till Diss

Over the past decade, the fashion industry has experienced a relatively high rate of consumption with material and clothing becoming increasingly subject to waste and disposal. As a result of the increased awareness within the industry the interest in CSR (Corporate Social Responsibility) amongst retailers has increased substantially in an attempt to shy away from the critically amplified media attention. In addition the underlying demand from external stakeholders has forced companies to ensure they focus and act upon each stage of the product life cycle.This study provides a further in depth analysis of the fashion industry and conveys the key messages and steps that firms are taking in response to the external pressures and requirements based on four different merged process areas. This research paper examines the impact of CSR on two Swedish fashion retailers Åhléns and JC and shows how accountability relates to the external expectations and norms that prevail in society. The result shows that the firms do meet the demands within each sub category as a response to market demands.

Thymidinkinas 1 som tumörmarkör vid juvertumörer hos tik :

Determination of serum thymidine kinase 1 (TK-1) activity is used as a tumour marker in both human and veterinary medicine. TK-1 is an intracellular enzyme involved in a salvage pathway of DNA synthesis. The expression of TK-1 is cell cycle dependent and the activity increases markedly after the G1 to S transition in the cell cycle and then declines rapidly in G2. The pronounced proliferative activity in tumour cells result in a higher TK-1 enzyme activity within the cell. The fact that the increased TK-1 activity can be measured in serum makes TK-1 a useful marker in diagnostics of neoplastic diseases and it provides information regarding prognosis and treatment effectiveness. In human medicine a radioactive based test is used to determine the TK-1 serum activity.

ESC-analys och studering av knack på en "Diesel Dual Fuel"-motor

A one-cylinder research engine has been used for studies with a Diesel Dual Fuel concept (DDF). DDF is a concept that utilizes a pilot diesel injection to ignite a homogenous natural gas/air mixture. Emissions and engine efficiency have been analyzed in an emission cycle called European Stationary Cycle (ESC) and the knock/pre-ignition problems with this type of engine have been investigated.At low and mid torque levels, an early diesel injection around 60 crank angles degrees (CAD) before top dead center (TDC) was used. At these loads raw NOxemissions was below EURO 6 level (0.2 g/kWh). NOxwas at EURO 5 level over the complete ESC without after treatment and with SCR at high loads it should be possible to reach EURO 6.One issue with DDF is the high HC emission levels.

Validering av Casmo-5M / Simulate-3

The objective of this M. Eng. Diploma work was to validate the new version, CASMO-5M, and compare the results with CASMO-4E, by using the same input in both programs. The tasks that were included in this work was to compare TIP-measures, k-effective curves (warm), k-effective curves (cold), the effect of void on k-effective, the isothermal temperature coefficient (ITC), the moderator temperature coefficient (MTC), damping ratio calculations, internal effect in a fuel bundle of a BA-rod, the speed of BA-out burn, impact of xenon, falling control rod, margins and isotopes.The TIP-measures showed that the differences were small for all reactors, at most, 6% nodal improvement by C5M (Casmo-5M) for Oskarshamn 3. The warm measurements of k-effective showed that C5M had a higher value for all cycles of Oskarshamn 1, 2 and 3 in comparison to C4E (Casmo-4E).

Are changes in heart rate and/or arborisation of vaginal mucus useful parameters for detecting heat in heifers? :

The milk production per cow has increased considerably during the last 50 years and due to the breeding for higher milk production also brings decreased reproduction efficiency. In a Swedish study 1996 it was shown that on average only half of all estruses were detected. Every time a farmer fails to detect oestrus it costs the farmer about 1200 Swedish crones and the need of means of detecting oestrus is therofore large. With this study we wanted to investigate if heart rate respectively crystallisation of vaginal mucus (arborisation) could be useful means of detecting oestrus. We monitored two oestrus cycles in four heifers.

Kvinnors preventivmedelsanvändning under olika faser av det reproduktiva livet

Introduction: Studies have shown that women are not always satisfied with the effects of contraception and that contraceptive advice is perceived as non-specific. Aim: The purpose of this study was to investigate what contraceptive women have chosen to use in the different phases of their reproductive lives, and what they felt had influenced their choice. Method: A retrospective cross-sectional comparative study with a quantitative approach. A survey with fixed and multiple-choice options was sent to five hundred 45-year old women. Result: The study shows that various birth controls are different in the normal reproductive life.

Anpassning och optimering av checkprogram för AW139

Presently Sjöfartsverket do their maintenance according to a standard program, which means that every maintenance task will be done when the task limit occurs. This leads to a very long downtime for the aircraft in some occasions and very short downtime in others. The goal with this work is to reach a higher regularity of the aircraft operation. To reach a higher regularity for the operational needs, this work will present a hypothetic better maintenance concept for Swedish Maritime Administration. The concept is based on equalized maintenance structure, which means that every maintenance occasions are meant to take the same time to perform.

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