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2147 Uppsatser om Impressed current - Sida 1 av 144

Katodiskt Korrosionsskydd : Hur fungerar katodiskt korrosionsskydd ombord på fartyg?

Idén till detta arbete uppstod som en följd av att vi på den fartygsförlagda praktiken upptäckt att kunskapen om katodiskt korrosionsskydd är mycket bristfällig hos många ombordanställda. Vi har även gjort en mindre undersökning bland yrkesverksamma maskinister för att se hur kunskapsnivån inom detta område ligger ombord. Undersökningen visar att vår hypotes om kunskapsnivån stämde till stor del. Ytterliggare ett skäl till att vi studerat det här området är att vi själva har velat fördjupa oss i ämnet, då våra egna erfarenheter endast varit att skriva av siffror från en display. Vår huvudfrågeställning har varit, Hur fungerar katodiskt korrosionsskydd ombord på fartyg? För att få svar på denna frågeställning har vi bedrivit litteraturstudier inom ämnet.

Konstruktion och utvärdering av Current Conveyors

Normally the operational amplifier is used as a component in active filter design. The goal for future components in filter design is large bandwith and the use of low supply voltages. The use of current-mode instead of voltage-mode circuits gets a step closer to the required performance. A component that use current as the signal conveying part is the current conveyor. In this report a comparative study between two current conveyor structures of second generation (CCII) is performed.

Konstruktion av current conveyors via makromodellering

A current conveyor is an active building block that can be used to implement most active and passive components. It differs from the operation amplifier in that it uses current instead of voltage. The current conveyor also has significantly higher voltage gain over a broader frequency range. To simplify the construction of analogue circuits and increase the construction efficiency it is desirable to use a top-down methodology. This means that the whole system is partitioned into a hierarchy of subsystems.

Den som vinner barnen, honom tillhör framtiden - Valfrid Palmgren och Stockholms barn- och ungdomsbibliotek 1911-1927

In 1911 Valfrid Palmgren founded the Children's Library of Stockholm, the very first in Sweden.She was a well-educated woman, who believed in social and educational equality for all.During a journey to the USA in 1907, she was deeply impressed by the public libraries, andshe put many of the public library ideas to use in the Children's Library of Stockholm. Palmgrenstrongly opposed to the Swedish libraries not allowing admission to children, since shefirmly believed that educating the people had to start with the children.Other reasons for opening a children's library were to give children an alternative to roamingthe streets, to give children a quiet place to read, to give an alternative to the cheap trashliterature that flooded the market and to teach the young ones how to extract information frombooks. Of great importance was that the library should be equal to all classes in society.In 1927 the children's library was taken over by the new public library of Stockholm..

Utvärdering av strömmätningar vid Höga Kusten : Strömmars betydelse för lokalisering av odlingslokaler och utformning av kontrollprogram i kustområden

A study was made to evaluate how current measurementscould help to determine how particles from fish farms are dispersed. During sixweeks of the summer 2012, two different current measurements were conducted.One of them consisted of measurements each fifth minute at 5 m and 15 m atthree locations for 14-16 days each. The other consisted of profilemeasurements at each location at four times during the period of six weeks. Forthe current measurements two instruments (model RCM 9) were used. A two weekmeasurement can give enough data to make an evaluation of how the currents at alocation will transport litter from a fish farm.

Teknikkonsultföretags anpassning inför en kommande lågkonjunktur

This thesis work is about how technical consulting companies can accept their organization before a coming recession. Technical consulting companies are together with the rest of the actors in the construction business constantly depended on the current economic situation on the market. How to adapt the organisation depends on the current situation on the market.To adapt the organization in the best way possible the companies need to recruit and educate personal. It is then very important to find a solution on how the current change of generation in the companies will be handled. The large and very much competent group of 40-talists will in a few years retire.

Kvalitetssäkring av Inleveranser

Through a thorough analysis of the current situation, we have highlighted differences inworking methods for the various workshops and drew up proposals for improvements incombination with a practical work description that can be implemented in the company..

Vakuumbrytare i småskaliga vattenkraftstationer

This master thesis has been performed at Vattenfall Power Consultant in Gothenburg and Trollhättan for Vattenfall Vattenkraft. In this report vacuum circuit breaker in small-scale hydropower stations with the rated power 4 MVA and below has been studied. Models of the stations are modeled and analyzed in PSCAD/EMTDC to study the high voltage transients that are created after current chopping with vacuum circuit breaker. Vacuum circuit breaker may chop the current before it reaches zero value, which means that high voltage transients can be created. The equipment of the stations can be destroyed by high voltage transients.The purpose of this thesis is to examine the use of vacuum circuit breaker in small-scale hydropower stations and the risk for high voltage transients from current chopping.According to the results there is a risk of high voltage transients after current chopping with small synchronous generators in stations with the operating voltages 0.4 kV and 3.6 kV.

Halvledare för höga strömmar i fordon

Mechanical relays are more and more being replaced with semiconductortechnology. In this thesis it is investigated if and how the larger loads couldbe controlled by transistors. The main part of this work aims to create andverify a solution that can control the starter motor, as well as protect it incase of any failure. The different malfunctions that the solution protectsagainst is high current, too high peak current, low current, maximum cranktime and minimum cool off time. The timers also protect indirectly againstoverheating of the starter engine.The transistors used are BTS555, from Infineon.

Väderstation

We got in contact with Marco AB, who we?ve had contact with before concerning earlier projects, to find out if they were interested in arranging a larger project for our last class (Examensarbete 15hp). They were very positive to this proposition, and soon they offered us a project regarding reconstruction of their current mechanical device that absorbs all the force from the lift itself when it is at a predefined level (sv. sjunkspärr). The current solution does fulfill the requirements that are given, however it is not a solution that gives a high level of satisfactory.

Fast driftställe enligt OECD:s modellavtal i ljuset av elektronisk handel

The purpose of this thesis is to examine whether the concept of permanent establishment, as defined in Article 5 of the OECD Model Tax Convention on Income and Capital, is applicable to electronic commerce and if so whether the current definition is able to appropriately deal with the challenges of electronic commerce.In 2003, the OECD added a new section to the Commentary on the Model Tax Convention on Article 5. The new section is a clarification on the application of the permanent establishment definition in electronic commerce.The current definition of permanent establishment in the Model Tax Convention relies on the physical presence of a foreign corporation as the threshold for source taxation. While the current definition, prima facie, might be applicable on electronic commerce, the highly mobile nature of electronic commerce might affect the current revenue distribution equilibrium between states..

Ström- och temperaturkontroll

Storing kinetic energy in a flywheel allows for more efficient driving of electricvehicles. Research in this area is in progress at Uppsala University, where a flywheelwith magnetic bearings encased in a vacuum chamber is being constructed. To makethis possible methods for measuring the current through the electromagnets in thebearings and temperatures in the flywheel need to be developed. This has been thepurpose of this report. The current measurement resulted in a resistive method, andthe implementation of eight measurement circuits in the system.

Utveckling av drivrutin till Intermec Easycoder 501 XP

We got in contact with Marco AB, who we?ve had contact with before concerning earlier projects, to find out if they were interested in arranging a larger project for our last class (Examensarbete 15hp). They were very positive to this proposition, and soon they offered us a project regarding reconstruction of their current mechanical device that absorbs all the force from the lift itself when it is at a predefined level (sv. sjunkspärr). The current solution does fulfill the requirements that are given, however it is not a solution that gives a high level of satisfactory.

Decentraliserad administration av gästkonton vid Karlstads universitet

We got in contact with Marco AB, who we?ve had contact with before concerning earlier projects, to find out if they were interested in arranging a larger project for our last class (Examensarbete 15hp). They were very positive to this proposition, and soon they offered us a project regarding reconstruction of their current mechanical device that absorbs all the force from the lift itself when it is at a predefined level (sv. sjunkspärr). The current solution does fulfill the requirements that are given, however it is not a solution that gives a high level of satisfactory.

Kalkylering i flygbranschen: En fallstudie av ett flygbolag

The purpose of this thesis is to analyse and propose improvements to the cost accounting system in use at an airline operating on the Swedish market. The choice of study object is based on the airline?s desire to have its cost accounting system evaluated. During the analysis we have identified a number of points where the current cost accounting system does not correspond to its intended purpose. These points include significant groups of costs not being considered in the current system, potential over capacity is not visible and logic connections between distribution keys and the use of resources are sometimes lacking.

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