Sök:

Sökresultat:

21 Uppsatser om Electromagnetic stirrer - Sida 1 av 2

Arkeologisk landskapsanalys och prospektering av bebyggelselämningar och gravfält vid Alsike hage

This paper deals with archaeological prospecting for the purpose of finding a prehistoric settlement in Alsike hage, Alsike parish, Uppland. The methods being used are soil phosphate analysis, electromagnetic survey and settlement analysis. Two 20x20 meters areas have been prospected. As Alsike hage contains several late Iron Age burial fields, large splendid zones for settlement location, closeness to water as well as farmland there was a hope of locating remains of prehistoric settlement in the area. None of the prospected areas showed any distinct evidence of settlement remains.

Lanczos potentialer i kosmologiska rumtider

We derive the equation linking the Weyl tensor with its Lanczos potential, called the Weyl-Lanczos equation, in 1+3 covariant formalism for perfect fluid Bianchi type I spacetime and find an explicit expression for a Lanczos potential of the Weyl tensor in these spacetimes. To achieve this, we first need to derive the covariant decomposition of the Lanczos potential in this formalism. We also study an example by Novello and Velloso and derive their Lanczos potential in shear-free, irrotational perfect fluid spacetimes from a particular ansatz in 1+3 covariant formalism. The existence of the Lanczos potential is in some ways analogous to the vector potential in electromagnetic theory. Therefore, we also derive the electromagnetic potential equation in 1+3 covariant formalism for a general spacetime.

Bioelectromagnetics for improved crop productivity : an introductory review with pilot study of pre-sowing treatment of tomato

Various electromagnetic (EM) treatments has been investigated for their potential in improving crop productivity over the past century. There is today an increasing amount of scientists advocating EM treatments as an organically compatible method for improving plant growth and yield. However, failure to produce repeatable effects and defining causal mechanisms has made it a study of much controversy and debate. The subject requires indepth interdisciplinary knowledge, making it inaccessible for the majority of biologists, horticulturists and growers. In this combined literature review and pilot study, these issues are addressed by providing a comprehensive introductory review of the topic plant bioelectromagnetics and its potential horticultural usability.

Solcellsdrivning av distribuerade inbyggda system

The high level of energy consumption that the industrialised countries have reached and thepollution that this brings has long been a cause for analysis and debate, development and usageof so called renewable energy sources is therefore more important than ever. The energy in theelectromagnetic radiation from the sun is an interesting alternative. One way of harvesting thisenergy is by using solar cells, devices that generate DC current when exposed to electromagneticradiation.The goal of this master?s thesis was to design a solar powered power supply to Syntronic AB?sMidrange platform. The envisioned application is a stand-alone distributed embedded system,for example a node-based temperature monitoring system.

En studie om artikelhantering i material- och produktionsstyrningssystem på System Andersson AB

This thesis aims to develop a control system for measuring electromagnetic compability (EMC). This has meant that a controller designed around an ATmega8 microcontroller has been manufactured and programmed. It has also meant the development of a comprehensive control software in the program MATLAB. The control system has been tested with satisfactory results and can now, monitor and control measurements of the EMC-type..

Magnetfält alstrade kring nätstationer i samband med lokaldistribution av elkraft : Magnetic fields generated by electrical substations during distribution of electric power

Abstract: This report covers primarily the work of documenting electromagnetic fields generated by one of the later parts in the electrical power distribution chain: The electrical substation, wherein 10 kV is transformed to 400 V for use by private consumers. Thus it is one of the most widespread and frequently occurring parts in the Swedish power grid and of particular interest, as electrical substations are found everywhere in populated areas, often in close vicinity to people and animals.The report deals with a number of formulated questions and/or hypothesis? stated at the onset of the work undertaken, theory that is relevant for the topics the report covers, the details of the field work undertaken and the following analysis of the readings, which in term provide answers for the questions stated in the beginning. It also covers what is the currently known short term and long term risks associated with electromagnetic fields in the power frequent spectrum and of varying intensity in the vicinity of humans.The analysis also provides recommendations and identifies several points to carefully consider when planning for new installations or replacements of some parts of existing installations.For enhanced reading comprehension there is, aside from sections with pictures and attached explanatory texts and templates, several graphs, one-line diagram and maps of the power grid among the appendixes to the rapport..

Aktiv ventilstyrning

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.

Utveckling av styrsystem för EMC-kammare

This thesis aims to develop a control system for measuring electromagnetic compability (EMC). This has meant that a controller designed around an ATmega8 microcontroller has been manufactured and programmed. It has also meant the development of a comprehensive control software in the program MATLAB. The control system has been tested with satisfactory results and can now, monitor and control measurements of the EMC-type..

Produktionsoptimering av elektromagnetiska omrörare - "ORD 43P" och "EM Stabilizer"

Examensarbetet inom produktutveckling ? konstruktion utfördes under perioden februari till juni 2013 och omfattar 15 högskolepoäng (C-nivå), och är den slutliga kursen inom högskoleingenjörsprogrammet Innovation och produktdesign.Examensarbetet behandlade problematiken kring produktionsanpassning och kostnadsoptimering av två stycken elektromagnetiska omrörare vid företaget ABB, Process Automation, Metallurgy i Västerås. Efter kontakt med handledaren från ABB, Jan-Erik Eriksson, påbörjades projektarbetet med att tillverkningsanpassa konstruktionen av produkterna ORD 43P och EM Stabilizer.För att åstadkomma kostnadsoptimerad och produktionsanpassad konstruktion tillämpade författarna följande produktutvecklingsverktyg: Design for Cost, Design for Manufacture och Design for Assembly. För att kontrollera att konstruktionen blev optimal, men också att den inte brister under belastning använde examensarbetarna det datorbaserade hållfasthetsverktyget finita elementmetoden i CAD-programmet SolidWorks.Val av komponenter baserades på komponenternas pris per kilo.För att välja det optimala materialet, det vill säga högsta hållfasthet till lägsta pris använde författarna materialdatabasprogrammet CES EduPack. De utvalda materialen från programmet kunde inte författarna påfinna som standard på marknaden, varför författarna ändrade strategi till att jämföra och välja material utifrån marknadsundersökning av standardmaterial hos leverantörer.  ORD 43Ps komponenter optimerades konstruktionsmässigt gentemot befintliga komponenter och härvstag och isolerplattor kostnadsreducerades markant.

Trådlös energiöverföring via elektromagnetisk induktion

This paper describes a method for wireless energy transfer via near-field electromagnetic inductionthat is inexpensive, simple and can be applied to almost any type of system, regardless of size andenergy demands.The method uses a primary unit consisting of an oscillator, amplifier and inductive coil thattransfers energy to a secondary unit consisting of a coil, rectifier and voltage regulator. Two typesof oscillators and several amplifier designs were realized and evaluated together with a multitudeof flat coils of both monofilar and bifilar type.The results show that it is important to use an oscillator whose frequency is dependent on theinductance of the connected transmission coil, such as the Colpitts oscillator. This is preferable toan oscillator with a preset frequency, such as a Schmitt-trigger oscillator..

Programvaruutveckling för en elektromagnetisk skanner med fokus på användaren, användarstudier och inlärning

The project was based on a request to improve an already existing program and hardware at the electrical engineering department at the royal institute of technology. For maximum ease of use, tests have been done on students to properly design the program for what it is meant to be used for. These tests have been transcribed and analysed, then brought back to the group in a discussion and then transcribed and analysed again, I call this process the ?four step process? (this process is presented and explained in chapter 6.4.). A part of this master thesis was also to analyse the four step process to enhance validity of this research.The project resulted in a new program with a new graphical view and features to help students and researchers to work with the technical tool for electromagnetic readings of planar objects.

Relationen mellan cyklister och fotgängare vid Södra Älvstranden, Göteborg En utvärdering av trafiken på cykelstråket Älvsborgsbron - Centrum

This paper describes a method for wireless energy transfer via near-field electromagnetic inductionthat is inexpensive, simple and can be applied to almost any type of system, regardless of size andenergy demands.The method uses a primary unit consisting of an oscillator, amplifier and inductive coil thattransfers energy to a secondary unit consisting of a coil, rectifier and voltage regulator. Two typesof oscillators and several amplifier designs were realized and evaluated together with a multitudeof flat coils of both monofilar and bifilar type.The results show that it is important to use an oscillator whose frequency is dependent on theinductance of the connected transmission coil, such as the Colpitts oscillator. This is preferable toan oscillator with a preset frequency, such as a Schmitt-trigger oscillator..

Optimering av antenndesign utifrån experimentella data

During the work at Gateway Security AB in Motala I began examining available antenna models to get a wider perspective, this have given knowledge of their structure, and an understanding of their function. All my necessary fact is based on my observations and notes of these measurings. New antenna models, and available models were examined where measurements at different heights and different distances on the antenna were performed with the help of an oscilloscope and a measure probe, peak ? to - peak was brought on the signal. The measurements are presented in a line diagram.

Malmmineralogisk undersökning av Pb-, Zn-, Cu- och Ag-förande kvartsgångar i Värmskogsområdet, mellersta Värmland

AbstractPolymetallic (Pb-Zn-Cu-Ag-Au-Sb-As-Bi-Cd-Te-Se-Ge?) quartz veins occur in an area from Eidsvoll in southeastern Norway to west of LakeVänern in southwestern Sweden. They most likely formed during the waning stage of the c. 1 Ga Sveconorwegian orogeny. In Värmskog parish, Värmland county, several mineralized quartz veins of different types are known.

Radomoptimering för luftburna störsändarkapslar

These studies are done in behalf of Saab AB AVITRONICS in Järfälla in the form of a thesis atthe Royal Institute of Technology in Stockholm.The task was to examine the parameters that plays a role in the construction of modern radomesoperating in broadband applications.This was interesting for Saab to get an indication of which way they should go at the newdevelopment of radomes for the next generation of equipment for electronic warfare.After a thorough analysis of the influencing parameters, a optimization application was made toget a automated way to get a radome design by specifying data on the radome size, airloads,materials, etc.This is to minimise the time of the laborious work that radome development.inply.This was solved by letting ANSYS calculate the strength of the radome structure and MATLABcalculate electromagnetic data and cost models of different sizes and materials.All these parameters woven together with the optimization tool modeFrontier picks data from therespective program and perform an optimization algorithm and then iterate a step and sends thisdata to calculation programs for the new input data. In the end, we have received a convergedpoint with our optimal solution.For the presumptions and limitations for which applied for this thesis, the result was prettyintuitive. That is to say that the smaller radome - the less materal is needed and lowermanufacturing costs results in the cheapest solution possible. The reality is not so simple. Whereyou have to take more of the electrical details such as the effect on the transmitter as a majorfactor..

1 Nästa sida ->