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1615 Uppsatser om Two phase flow - Sida 1 av 108

Modellering av ett bränslesystem i Modelica : tillämpat på ett obemannat flygplan

Mathematical models possible to simulate are of great importance in order to make successful projects in the aircraft manufacturing industry. An aircraft fuel system is very complex, containing pipes, tanks, orifices, valves and pumps. The principal of this thesis is using the tool Easy5, which no longer is considered reliable enough in terms of development and support. This thesis tries to evaluate the Modelica language as a possible alternative to Easy5. To make this evaluation, the components concerned in the fuel library in Easy5 are implemented to the Modelica language.

Projektanalys vid Stora Enso Packaging Concept i Torsvik

In a global economy it is important to understand what project management is and how it functions in a contemporary company. This report includes an empirical case study of a project flow, which was conducted in the department Packaging Concept (PC) which is a part of Stora Enso. As all of PC´s customer enquiries are unique and must be considered an individual project, PC continuously works in projects. An analysis of the project flow was conducted based on interviews at and visits to PC as well as relevant documents distributed by the department. The report gives an understanding and analysis of how PC works in projects.

Kappa Control with Online Analyzer Using Samples from the Digester's Mid-phase

In the pulp industry, digesters are used to disolve lignin in wood chips. The concentration of lignin is measured and is called the Kappa number. In this thesis, the question of whether an online Kappa sensor, taking samples from the mid-phase of the digester, is useful or not is analyzed. For the samples to be useful, there has to be a relationship between the measured Kappa at the mid- phase and the measured Kappa in the blowpipe at the bottom of the digester. An ARX model of the lower part of the digester has been estimated.

VÄRDEFLÖDESANALYS AV PW1000G 30k TEC

The thesis work has been carried out at Volvo Aero Corporation (VAC) in Trollhättan. VAC has entered a partnership as developing and producing partner with engine manufacturer Pratt & Whitney and is currently at the starting phase of producing the turbine rear frame (TEC) to the engine PW1000.The purpose of this study was to create a report on process level that describes the conditions and the potential with PW1000 TEC to reach the product cost calculation taking into account lead times and describe alternative method solutions.The report describes a comparison between the present flow (2012), a flow based on product cost calculation (2016) and a potential flow (2016). The work has mainly been based on acquiring the knowledge and information available to inspect the present flow; this has been done by workshop observations, meetings and gathering of the information that is available on the work site for the PW1000 TEC.The information obtained has been merged into an Excel document, called Roadmap. It serves as a roadmap with current situation as the start and the potential flow for 2016 as the goal. With the roadmap as a tool, assumptions have been taken considering the flow and how it will change, where processes have been eliminated, reduced or marked as a problem..

Fenomenet complete phase : incomplete phase i rotumanska

I denna uppsats behandlas de grammatiska fenomenen complete phase och incomplete phase i det austronesiska språket rotumanska. Min avsikt med uppsatsen är att ta reda på varför complete phase respektive incomplete phase används i en viss syntaktisk eller morfologisk kontext. Jag har baserat denna studie endast på litteratur, främst från C.M Churchwards Rotuman Grammar and Dictionary..

Betydelsen av flow i bildskapande och pedagogers betydelse för flow : En uppsats inom bildpedagogik om flow och kreativitet och vilka förutsättningar som gynnar flow.

Uppsatsen behandlar ämnet genus och genusframställningen i barnböcker nu, och för 50 år sedan. För att komma fram till ett resultat har två analysmetoder använts, Nikolajevas mimetiska metod samt en semiotisk bildanalysmetod. Resultatet visar att det skett en förändring av genusframställandet i barnböcker de senaste femtio åren och att den största förändringen skedde i mitten på 60-talet..

Surgical stress response in dogs diagnosed with pyometra undergoing ovariohysterectomy

The aim of this study was to investigate the intraoperative surgical stress response in dogs undergoing ovariohysterectomy and to compare acepromazine and medetomidine as premedications. 15 dogs diagnosed with pyometra were used in this study. Blood pressure and heart rate were used as parameters to measure surgical stress response. The surgery was divided into four phases. Phase 0 was the period 10 minutes before the skin incision, phase 1 was skin incision and opening of abdomen, phase 2 was manipulation of uterine horns, ligation and transection of mesovarium and phase 3 was ligation of cervix, removal of organs and closing the abdomen. The results showed that phase 2 was the most intense phase of surgical stress, regardless of which premedication the dogs received. When acepromazine and medetomidine were compared the results showed that within phase 3, all dogs that were given medetomidine had higher blood pressure compared to dogs that were given acepromazine. The dogs that were given acepromazine had higher heart rate than the dogs that were given medetomidine in phase 0, phase 2 and phase 3. .

Utvärdering av Vissberga lakvattenbehandling

In connection with the admittance of the EC-directive (99/31/EC) in Swedish politic, through the constitution of waste depositing (2001:512) at year 2001, the rules about management the landfills and leachates tightened. At the landfill Vissberga in the municipality of Hallsberg, a leachate treatment plant was constructed just a year thereafter. This treatment plant consisted of an aerated pond with a following land treatment and a willow cultivation to replace the land treatment during the summer. In this case the parameters, which were estimated as the most important to reduce, were iron and nitrogen. The iron would react with the oxygen-rich water in the aerated pond and precipitate to ferric-hydroxide and than settle in a calm zone of the pond.

Misslyckade IT-projekt : Vilken fas i systemutvecklingens livscykel är mest bidragande

Many IT projects that have been developed in recent years are often considered to be unsuccessful. According to a study by Exido up to the 72% of all IT projects are considered to be failed. A failed IT projects means that the organizations that have ordered the new system may have higher costs or/and the system will not be ready in time. If costs are too high the new system might not be installed in the organization or if the system is not completed within the specified time frame the organization can become stagnant.In this paper we conduct an investigation of the failure of IT projects there we will examine where, in the systems development lifecycle four different phases, projects fail. We will conduct an empirical study of each phase, where we describe the key steps in the process; we will also investigate failed IT projects that are linked to the current phase.

Ledarskapsutbildning ? till nytta eller nöje för Kommunstyrelsens ordförande? : En uppsats om betydelsen av ledarskapsutbildning

Many IT projects that have been developed in recent years are often considered to be unsuccessful. According to a study by Exido up to the 72% of all IT projects are considered to be failed. A failed IT projects means that the organizations that have ordered the new system may have higher costs or/and the system will not be ready in time. If costs are too high the new system might not be installed in the organization or if the system is not completed within the specified time frame the organization can become stagnant.In this paper we conduct an investigation of the failure of IT projects there we will examine where, in the systems development lifecycle four different phases, projects fail. We will conduct an empirical study of each phase, where we describe the key steps in the process; we will also investigate failed IT projects that are linked to the current phase.

Utveckling av en LC-MS-metod för analys av gamma-hydroxibutyrat, gamma-butyrolakton, 1,4-butandiol, amfetamin och metadon

In this project a LC-MS-method for the analysis of gamma-hydroxybutyrate, gamma-butyrolactone, 1,4-butanediol, amphetamine and methadone was developed.Initially, the efficiency of the ionisation of the analytes was evaluated with respect to the ionisation technique (ESI, APCI and APPI) and the composition of the mobile phase. In the next step a number of different columns was tested in order to find the one with the greatest potential for separation of the substances in question. Using the selected column, the separation was optimised by means of experimental design and the software The Unscrambler 7.8. The parameters studied were the flow rate, the column temperature and the mobile phase composition. The response variables were the resolution between the target compounds and the retention time of the last eluting compound.These experiments showed that, in order to obtain the best ionisation, the mobile phase should consist of 5 mM formic acid in water and acetonitrile.

Porten till förståelse: svenska bibliotek och invandrare

The purpose of this paper was to investigate the special services for immigrants which are offered by Swedish libraries on their different levels regional, local and school as well as immigrants experiences of the library services and how these services and experiences conduct themselves to the development of the harmonic multicultural society. The methods used were interpreting reflexive interviews with immigrants and librarians. The guiding theory in this study was a three-phase model by Gillis Herlitz according to which a newcomer goes through three stages in an adaptation period. Phase 1 is a positive honeymoon phase, that later is replaced by phase 2, a critical disappointment period, which then ideally should be resolved in phase 3, where the individual reaches a balancing stage of cultural adaptation. The results of my observations indicate that the performances of the different libraries seem to operate in a way that corresponds to the different phases in this model.

The control of the cell cycle with particular emphasis on the G1/S transition

Tumour development occurs to a large extent because of dysregulation of the cell cycle. Of particular importance are defects occurring in the G1 phase. The reason why G1 is critical is because of the influence of several signals (external signals as well as cyclins and cdks) on this stage. The G1 phase can be divided into two parts, G1pm and G1ps. Each part has its ?own? restriction point which needs to be passed in order to progress to S phase.

Utveckling av flödesreaktor : Ett sammarbetesprojekt mellan fakulteten för teknik och naturvetenskap vid Uppsala Universitet och Fagrell produktutveckling AB

 This report deals with thecollaborative project between FagrellProdukt Utveckling AB and studentsfrom the Faculty of Science andTechnology at Uppsala University. Theoverall objective of the project wasin addition to developing students'abilities, to help Fagrell withverification and development ofFagrells prototype, Fundamental flowreactor, for flow chemistry. Theuniqueness of Fagrells flow reactor isthat it should be simple andaffordable compared to competing flowreactors in the market.The verification was done bylaboratory and simulation sessions.The verification shows that Fagrellsidea on how to construct a flowreactor is very good.The development included bothtechnology and business. The result ofdevelopments can be helpful for thecommercialization of Fagrell flowreactor..

The role of cell cycle control mechanisms in regulated and sustained cell proliferation

The cell cycle is the time a cell spends between two cell divisions. The cell cycle includes several parallel processes, all of which must be completed before a cell is mature for dividing. In the first place, all subcomponents (RNA, protein and membrane lipids) need to double in quantity and this occurs continuously through the cell cycle. Furthermore, the genome and some chromosomal proteins must double and this take place during a limited interval in the middle of the cell cycle (S-phase). On either side of the S-phase are two "gaps" which is called G1 and G2. When the cell has passed a point in the G-phase they are irreversibly programmed to progress through the remaining of the cell cycle and will undergo the next cell division. When a cell have passed a point in the G1 phase, approximately four hours after mitosis, a normal cell is in a state of indecision.

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