In this bachelor thesis, diagnostic methods for one of Siemens stem inlet control valves have been developed. The work has taken place during ten weeks at Siemens Industrial Turbomachinery AB in Finspång. The company produce steam- and gas turbines and also provides service and maintenance. The purpose with this project has been to develop diagnostic methods that oversee the health of the control valves. By using the developed methods you will know when it?s time for maintenance.

This literature study aims to examine the existence of cancer stem cells in breast cancer. The cancer stem cell theory states that there is a hierarchical organization within a tumour, in which a small subpopulation of the cells can initiate new tumours and maintain tumour growth whilst the bulk of the tumour cannot. These tumour initiating cells have shown to possess many characteristics similar to those of adult stem cells, which is why they are often referred to as cancer stem cells. Both cell types have the capacity of asymmetric division and have shown to possess mechanisms of resistance to both apoptosis and cancer drugs. The cancer stem cell theory elucidates many biological aspects such as the heterogeneity of tumours and the relapse of many cancers after what appeared to be successful treatments.

Examensarbetet har genomförts på Siemens Industrial Turbomachinery AB i Finspång. Arbetet innebär modernisering av ventiler till ångturbiner. Uppgiften består av två delar, där den första delen är att modernisera dagens tätningar i spindelgenomföringen. Syftet är att finna en mer vibrationstålig, driftsäker och mindre utrymmeskrävande lösning. Det andra delprojektet är att finna alternativ till dagens tallriksfjädrar i de servomotorer som reglerar ventilen.

To achieve an optimal combustion, an even air/fuel ratio in the combustion chamber is required. An optimal combustion leads to reduced amount of emissions due to a more complete combustion, which is an important matter because of the sharpened environmental laws. This can be attained, among other things, by applying entirely variable cam times. To optimize the engines efficiency and its emissions at all workloads and speeds, an active valve control can be applied. This means that the intake and exhaust-valves can be opened and closed at any time, independent of the crankshaft position.

Regulations on the exhaust emissions of HD-diesel engines are becoming more and more stringent, and therefore, emission after-treatment systems are commonly used. These systems rely on catalytic conversion of NOx,CO , and HC emissions, and are thus dependant on temperature. At low load of the engine, exhaust temperatures are not sufficient for the after-treatment components. Therefore, means to increase the exhaust temperature while maintaining low emissions and fuel consumption are needed.The focus of this project has been to develop strategies for the lift profiles of exhaust and intake valves in the engine, with the goal to raise exhaust temperature in combination with low emissions and fuel consumption. The strategies have been tested in a single-cylinder research engine equipped with a hydraulic variable valve actuation system.

At nuclear power plants, electrical valve actuators are important for ensuring that the reactor core is water covered and the pressure in the reactor tank and containment is limited. The electrical actuators are provided with overload protection in case of drawing higher current then the motors are rated for. When safety manoeuvres are needed, the overload protection must not trig and cause the valve to stop before completing the manoeuvre. Analyses have showed that the current settings of the overload protection may cause an illegitimate trig at the worst theoretically possible accident. A new method has been developed with conservative assumptions and applies overload protections for all electrical valve actuators at the three reactors in Forsmark..

Stjärnägg is a sales organization operating on the Swedish eggmarket, owned by nine Swedish packing companies. Those nine packing companies are not just owners of the sales organization, but at the same time competitors since they compete in the market when they do not sell the eggs through Stjärnägg.The purpose of this thesis is to evaluate the sales organization from a supplier and owner perspective. To answer the purpose of this study, qualitative interviews have been conducted with the owners of the egg packers. This has been done in order to get as fair picture of the sales organization as possible. From the answers of the interviews, a compilation has been made to be able to give Stjärnägg concrete proposals of improvements in the organization.

Because of new emission and on board diagnostics legislations, heavy truck manufacturers are facing new challenges when it comes to improving the engines and the control software. Accurate and real time executable engine models are essential in this work. One successful way of lowering the NOx emissions is to use Exhaust Gas Recirculation (EGR). The objective of this thesis is to create a mean value model for Scania's next generation EGR system consisting of a poppet valve and a two stage cooler. The model will be used to extend an existing mean value engine model.

This report contains a degree project made by the mechanical engineering students Lennart Andersson and Daniel Jansson. The project has performed in assignment by SOMAS Valves AB in Säffle. SOMAS are leading in development on control and on/off valves. To maintain this position they always want to improve their products. One way in this development is valves that are more tightened.The purpose with our project was to investigate another seat design on a HiCo (High Cobalt Alloy) seat to a SKV 150 PN 25 valve and compare this to an original HiCo seat.By modifying the seat on a ball valve we want to achieve a valve that leaks lesser then a valve whit original seat.

The purpose of this paper is for the reader to realise how national innovation systems are deeply intertwined with the legal background of a country and to understand the processes that involves national innovation systems specifically regarding the stem cell / genetics research and how the need for specific community law must be considered targeting the stem cell patents. The legal part will try to answer: Why is it important given the actual state of the European stem cell national innovation systems for the European Commission to take a stand and tackle issues regarding the patenting of the human stem cell innovations? This is done from a country industry analysis (business approach) and then linking it with competition law from a community stand point of view (that tackles biotechnology issues). In order to achieve this the paper is divided into three separate analyses beginning with a theoretical background of general biotechnology / genetic terms that will enable the reader to have a general understanding of the importance of this kind or research ( genetics / stem cell research). The chosen countries case studies exemplify very diverse economies and development perspective from the traditionally R&D intensive to the least and from the biggest countries in Europe to one of the smallest, thus giving cultural, legal, economic and scientific variety..

In this master thesis a robot arm belonging to an automatic milking machine from DeLaval is investigated. The robot arm is controlled by a pneumatic cylinder and a valve. The goal of the master thesis is to investigate instability problems and to find out if it is possible to solve them by using gain scheduling. Gain scheduling is a type of controller where the parameters of the controller are changed during operation, for example depending on the working point. First a nonlinear mathematical model of the system was made.

Aortic insufficiency is a very common valve problem in horses and most often affects older individuals, but nevertheless existent within younger ones. The root cause for aortic insufficiency can be varied, for example; endocarditis, ventricular septum defect or congenital valve disease but the most common are progressive valve degeneration or elite competition. Depending on the root cause, different changes can be observed on the aorta valves, but they do all have the same effect, the valves do not seal properly and blood leaks backwards. Many horses can, even with this deficiency, perform highly without any visible impacts and there is therefore no need to treat those subjects. Most often the symptoms arise at a later stage in life and they are, more often than none, put down for other reasons. In the occurrence of the clinical symptoms showing, treatment guideline is to inhibit these symptoms since the valve degeneration is presently irreversible.

The aim of this study is to investigate how multiple tree handling harvesters perform compared to earlier developed standards. The study shows that multiple tree handling harvesters are more efficient in thinnings stands with mean stock volumes less than 0,12 m3fub per stock. The increased efficiency is different for different mean stem classes. In stands with a mean stem volume of 0,04 m3fub per stock, the increase can be as high as 40 percent while it is about 10 percent in stands with a mean stem volume of 0,12 m3fub. Comparisons have been done between stands that are felled with partly limbed stands and stands without partly limbed assortments. The difference in performance is clear and shows that the partly limbed assortments strengthen the multiple tree handling harvesters positive effects in low dimension thinnings.

The Homogeneous Charge Compression Ignition (HCCI) engine is promising in terms of lowNOx, low particulates and high efficiency. Due to its homogeneous charge, where thecombustion starts almost simultaneously from a number of points in the combustion chamber,only lean mixtures are possible to burn because of the resulting rapid combustion, which is muchfaster than the combustion in an SI-engine or a diesel engine. When richer mixtures are used thecombustion will start earlier and also be more violent.To phase the combustion later and lower the combustion speed, external cooled EGR can beused. The EGR-system used in this thesis uses a divided exhaust channel where one channel andits corresponding valve are used only for transporting EGR back to the intake system.Consequently the EGR-valve is connected to the intake pressure. This system is called Direct-EGR (D-EGR).Engine tests verified that the CA50 indeed is phased later when cooled EGR is used.

The aim of this study is to describe a number of type stands of lodge pole pine in Norrbotten with respect on stem volume and total biomass. Further questions to answer is if there is stand characteristics that make the stands more suitable for pulpwood in early thinning, or if it is better to apply whole tree harvest. The study shall also give an indication if bio energy can be an economical interesting alternative for Sveaskog. Sampled trees represented the variation in the different stands. Five trees were selected from each stand to represent that stand. Stem volume and biomass (kg dry weight (DW) per hectare) for each fraction was calculated.