Electrical Machine Product Development; Transmission to Lean Approach

The requirements set by the market for electrical machines become increasingly demanding requiring more sophisticated technological solutions. Companies producing electrical ma-chines are challenged to develop machines that provide competitive edge for the customer for example through increased efficiency, reliability or some customer specific special requirement. The objective of this thesis is to derive a proposal for the first steps to transform the electrical machine product development process of a manufacturing company towards lean product development. The current product development process in the company is presented together with the processes of four other companies interviewed for the thesis. On the basis of current processes of the electrical machine industry and the related literature, a generalized electrical machine product development process is derived. The management isms and –tools utilized by the companies are analyzed. Adoption of lean Pull-Event –reviews, Oobeya –management and Knowledge based product development are suggested as the initial steps of implementing lean product development paradigm in the manufacturing company. Proposals for refining the cur-rent product development process and increasing the stakeholder involvement in the development projects are made. Lean product development is finding its way to Finnish electrical machine industry, but the results will be available only after the methods have been implemented and adopted by the companies. There is some enthusiasm about the benefits of lean approach and if executed successfully it will provide competitive edge for the Finnish electrical machine industry.

Energy Efficiency Consideration in Electric Vehicle Transmission

This study is a survey of benefits and drawbacks of embedding a variable gearbox instead of a single reduction gear in electric vehicle powertrain from efficiency point of view. Losses due to a pair of spur gears meshing with involute teeth are modeled on the base of Coulomb’s law and fluid mechanics. The model for a variable gearbox is fulfilled and further employed in a complete vehicle simulation. Simulation model run for a single reduction gear then the results are taken as benchmark for other types of commonly used transmissions. Comparing power consumption, which is obtained from simulation model, shows that the extra load imposed by variable transmission components will shade the benefits of efficient operation of electric motor. The other accomplishment of this study is a combination of modified formulas that led to a new methodology for power loss prediction in gear meshing which is compatible with modern design and manufacturing technology.

Power-line-communication-based data transmission concept for an LVDC electricity distribution network – Analysis and implementation

Communications play a key role in modern smart grids. New functionalities that make the grids ‘smart’ require the communication network to function properly. Data transmission between intelligent electric devices (IEDs) in the rectifier and the customer-end inverters (CEIs) used for power conversion is also required in the smart grid concept of the low-voltage direct current (LVDC) distribution network. Smart grid applications, such as smart metering, demand side management (DSM), and grid protection applied with communications are all installed in the LVDC system. Thus, besides remote connection to the databases of the grid operators, a local communication network in the LVDC network is needed. One solution applied to implement the communication medium in power distribution grids is power line communication (PLC). There are power cables in the distribution grids, and hence, they may be applied as a communication channel for the distribution-level data. This doctoral thesis proposes an IP-based high-frequency (HF) band PLC data transmission concept for the LVDC network. A general method to implement the Ethernet-based PLC concept between the public distribution rectifier and the customerend inverters in the LVDC grid is introduced. Low-voltage cables are studied as the communication channel in the frequency band of 100 kHz–30 MHz. The communication channel characteristics and the noise in the channel are described. All individual components in the channel are presented in detail, and a channel model, comprising models for each channel component is developed and verified by measurements. The channel noise is also studied by measurements. Theoretical signalto- noise ratio (SNR) and channel capacity analyses and practical data transmission tests are carried out to evaluate the applicability of the PLC concept against the requirements set by the smart grid applications in the LVDC system. The main results concerning the applicability of the PLC concept and its limitations are presented, and suggestion for future research proposed.

Software and Code Finder: making research outputs visible

Poster at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

Comparison study of two competing models of an all mechanical power transmission system

A comparison between two competing models of an all mechanical power transmission system is studied by using Dymola –software as the simulation tool. This tool is compared with Matlab/ Simulink –software by using functionality, user-friendliness and price as comparison criteria. In this research we assume that the torque is balanceable and transmission ratios are calculated. Using kinematic connection sketches of the two transmission models, simulation models are built into the Dymola simulation environment. Models of transmission systems are modified according to simulation results to achieve a continuous variable transmission ratio. Simulation results are compared between the two transmission systems. The main features of Dymola and MATLAB/ Simulink are compared. Advantages and disadvantages of the two softwares are analyzed and compared.

The obstacles for cross-border transmission network investments in the Nordic electricity market: Case South-West link

The Nordic electricity market is often seen as an example of how to create a working, developed and integrated electricity market. Nevertheless, this thesis studies the obstacles of transmission network investments and the market integration challenges in the Nordic electricity market. The main focus is in the Nordic Transmission system operators (TSOs), which have a key role in grid development. This study introduces a case study of cancellation of South-West link, Western part, which was seen as essential grid investment in order to improve the Nordic electricity market functioning but ended up with cancellation in 2013. This study includes semi-structured theme interviews of the experts among Nordic electricity industry stakeholders. Despite the political will to create more equal prices for electricity in the Nordic market, the differing national regulation, mixed incentives created by bottleneck income and the focus moving from Nordic integration to European integration may create challenges to the Nordic electricity market integration in the future.

NIR-Vis Up-Conversion Luminescence in the Yb3+,Er3+ Doped Y2O2S, ZrO2, and NaYF4 Nanomaterials

Since the discovery of the up-conversion phenomenon, there has been an ever increasing interest in up-converting phosphors in which the absorption of two or more low energy photons is followed by emission of a higher energy photon. Most up-conversion luminescence materials operate by using a combination of a trivalent rare earth (lanthanide) sensitizer (e.g. Yb or Er) and an activator (e.g. Er, Ho, Tm or Pr) ion in a crystal lattice. Up-converting phosphors have a variety of potential applications as lasers and displays as well as inks for security printing (e.g. bank notes and bonds). One of the most sophisticated applications of lanthanide up-conversion luminescence is probably in medical diagnostics. However, there are some major problems in the use of photoluminescence based on the direct UV excitation in immunoassays. Human blood absorbs strongly UV radiation as well as the emission of the phosphor in the visible. A promising way to overcome the problems arising from the blood absorption is to use a long wavelength excitation and benefit from the up-conversion luminescence. Since there is practically no absorption by the whole-blood in the near IR region, it has no capability for up-conversion in the excitation wavelength region of the conventional up-converting phosphor based on the Yb3+ (sensitizer) and Er3+ (activator) combination. The aim of this work was to prepare nanocrystalline materials with high red (and green) up-conversion luminescence efficiency for use in quantitative whole-blood immunoassays. For coupling to biological compounds, nanometer-sized (crystallite size below 50 nm) up-converting phosphor particles are required. The nanocrystalline ZrO2:Yb3+,Er3+, Y2O2S:Yb3+,Er3+, NaYF4:Yb3+,Er3+ and NaRF4-NaR’F4 (R: Y, Yb, Er) materials, prepared with the combustion, sol-gel, flux, co-precipitation and solvothermal synthesis, were studied using the thermal analysis, FT-IR spectroscopy, transmission electron microscopy, EDX spectroscopy, XANES/EXAFS measurements, absorption spectroscopy, X-ray powder diffraction, as well as up-conversion and thermoluminescence spectroscopies. The effect of the impurities of the phosphors, crystallite size, as well as the crystal structure on the up-conversion luminescence intensity was analyzed. Finally, a new phenomenon, persistent up-conversion luminescence was introduced and discussed. For efficient use in bioassays, more work is needed to yield nanomaterials with smaller and more uniform crystallite sizes. Surface modifications need to be studied to improve the dispersion in water. On the other hand, further work must be carried out to optimize the persistent up-conversion luminescence of the nanomaterials to allow for their use as efficient immunoassay nanomaterials combining the advantages of both up-conversion and persistent luminescence.

The estimation of tuberculosis transmission parameters using ABC and MCMC methods

The aim of this work is to apply approximate Bayesian computation in combination with Marcov chain Monte Carlo methods in order to estimate the parameters of tuberculosis transmission. The methods are applied to San Francisco data and the results are compared with the outcomes of previous works. Moreover, a methodological idea with the aim to reduce computational time is also described. Despite the fact that this approach is proved to work in an appropriate way, further analysis is needed to understand and test its behaviour in different cases. Some related suggestions to its further enhancement are described in the corresponding chapter.

Photocatalysis Studies under Visible Light Irradiation with TiO2 Obtained by Pulsed Electric Field Assisted Sol-Gel Method

The objective of this thesis was to study the effect of pulsed electric field on the preparation of TiO2 nanoparticles via sol-gel method under the visible light irradiation. The literature part introduces properties of different TiO2 crystal forms and principle of photocatalysis. It was expected that pulsed electric field would have an influence on degradation for oxalic acid and formic acid. TiO2 samples were prepared by using three frequencies (50Hz, 294Hz, and 963Hz) and two treatment times (12 minutes and 24 minutes) of pulsed electric field. The photocatalytic activities of TiO2 samples produced with sol-gel method were also compared with the TiO2 particles made by previous study and with the commercial TiO2 powder Aeroxide® (Evonic Degussa GmbH) at the same condition. Results show that pulsed electric field does have an effect on degradation for oxalic acid and formic acid. Generally, higher photocatalytic activities for oxalic acid and formic acid were obtained with lower frequency and longer treatment time of pulsed electric field.

Mistä on hyvät tytöt tehty? Somalitytöt ja maineen merkitykset

Tutkimus käsittelee islaminuskoisten somalityttöjen hyvään ja huonoon maineeseen liittyviä uskonnollisia, kulttuurisia ja etnisiä määrittelyjä ja niiden merkityksiä heidän arjessaan. Turussa hankittu etnografinen tutkimusaineisto koostuu osallistuvaan havainnointiin perustuvasta kenttäpäiväkirja-aineistosta sekä kahdestakymmenestäviidestä 17‒35-vuotiaiden somalityttöjen ja -naisten teemahaastattelusta vuosilta 2003–2006. Tutkimuksen tehtävänä on selvittää, minkälaista somalityttöä pidetään maineeltaan hyvänä ja miten tytön maine voi mennä. Tutkimuksessa tarkastellaan yhtäältä sitä, mikä merkitys sosiaalisilla verkostoilla on tyttöjen maineen määrittelyssä. Toisaalta kysytään, mitä somalitytöt ja nuoret naiset itse ajattelevat tytön maineeseen liittyvistä odotuksista ja miten he niistä tietoisina toimivat. Lähestymistapa rakentuu uskontotieteen, antropologian, sukupuolentutkimuksen, tyttötutkimuksen, nuorisotutkimuksen ja kulttuurimaantieteen näkökulmia yhdistelemällä. Ensimmäisessä aineistontulkintaluvussa tarkastellaan tyttöyteen ja maineen rakentumiseen liittyvää ruumiillista merkityksenantoa pukeutumisen, seksuaalisuuden, tyttöjen ympärileikkausta koskevan asennemuutoksen ja seurustelun teemojen kautta. Toisessa luvussa keskitytään kaupunkitilan ja tyttöjen vapaa-ajanvieton sosiotilallisiin tulkintoihin sekä tyttöjen käytöstä kodin ulkopuolella määritteleviin ja mainetta rakentaviin puheisiin. Haastatellut arvostivat islamiin ja somaliperinteeseen liittyviä arvoja ja pitivät niitä oman käytöksensä ohjenuorina. Omanarvontunto, itsekontrolli ja vastuuntunto omista teoista liitettiin ”hyvään tyttöyteen”. Tyttöjen toimijuus ilmeni heihin kohdistuvien odotusten suuntaisena käyttäytymisenä ja näiden ihanteiden arvostamisena. Toimijuus näkyi myös tiettyjen tyttöihin ja poikiin kohdistuvien erilaisten odotusten kyseenalaistamisena ja joissakin tapauksissa vastoin odotuksia toimimisena. Turkua myös verrattiin somalityttöjen käytöksen osalta pääkaupunkiseutuun. Tässä vertailussa Turku nimettiin kulttuurisen jatkuvuuden, pääkaupunkiseutu kulttuurisen muutoksen paikaksi. Haastateltujen mukaan yhteisöllisiä tulkintoja tyttöjen käytöksestä tehtiin puheissa ja juoruissa, usein suhteessa havaintoihin suomalaistyttöjen käytöksestä. Tyttöjen arkeen nämä etniset ja moraaliset eroteot eivät kuitenkaan vaikuttaneet aina samalla tavoin, koska tulkinnat tyttärille sopivasta ja mahdollisesta käytöksestä voivat vaihdella perheiden välillä. Tutkimus tuo esille, että tytön hyvä maine on eräs perheen hyvinvointiin vaikuttavista tekijöistä. Somalityttöjen käytös on myös eräs yhteisöllinen peili, jota vasten tehdään laajempia tulkintoja somalikulttuurin ja uskonnollisten arvojen tilasta diasporassa. Liiallinen muutos tyttöjen käyttäytymisessä uhkasi yhteisöllistä jatkuvuutta ja uskonnolliskulttuuristen arvojen välittymistä seuraaville sukupolville. Laajasti ymmärrettynä ”hyvä tyttöys” ja hyvä maine oli onnistuneen kulttuurisen neuvottelun tulosta diasporassa. Se tarkoitti, että tyttö kiinnittyi somalialaiseen taustaansa ja sen välittämiin arvoihin, osallistuen samalla kuitenkin myös suomalaiseen yhteiskuntaan.

Cross-border transmission capacity development – Experiences from the Nordic electricity markets

The liberalisation of the wholesale electricity markets has been considered an efficient way to organise the markets. In Europe, the target is to liberalise and integrate the common European electricity markets. However, insufficient transmission capacity between the market areas hampers the integration, and therefore, new investments are required. Again, massive transmission capacity investments are not usually easy to carry through. This doctoral dissertation aims at elaborating on critical determinants required to deliver the necessary transmission capacity investments. The Nordic electricity market is used as an illustrative example. This study suggests that changes in the governance structure have affected the delivery of Nordic cross-border investments. In addition, the impacts of not fully delivered investments are studied in this doctoral dissertation. An insufficient transmission network can degrade the market uniformity and may also cause a need to split the market into smaller submarkets. This may have financial impacts on market actors when the targeted efficient sharing of resources is not met and even encourage gaming. The research methods applied in this doctoral dissertation are mainly empirical ranging from a Delphi study to case studies and numerical calculations.

Ultrastructural changes of Fusobacterium nucleatum as a defense mechanism against human neutrophil peptide-1 - A Transmission Electron Microscopy (TEM) study

Aims: The aim of this work was to assess the ultrastructural changes, cellular proliferation, and the biofilm formation ability of F. nucleatum as defense mechanisms against the effect of HNP-1. Materials and methods: The type strain of F. nucleatum (ssp. nucleatum ATCC 25586) and two clinical strains (ssp. polymorphum AHN 9910 and ssp. nucleatum AHN 9508) were cultured and incubated with four different test concentrations of recombinant HNP-1 (1, 5, 10 and 20 µg/ml) and one control group (0 µg/ml). Bacterial pellets from each concentration were processed for TEM imaging. Planktonic growth was assessed and colony forming units (CFU) were measured to determine the cellular proliferation. Scrambled HNP-1 was used for confirmation. Results: TEM analyses revealed a decrease in the outer membrane surface corrugations and roughness of the strain AHN 9508 with increasing HNP-1 concentrations. In higher concentrations of HNP-1, the strain AHN 9910 showed thicker outer membranes with a number of associated rough vesicles attached to the outer surface. For ATCC 25586, the treated bacterial cells contained higher numbers of intracellular granules with increasing the peptide concentration. Planktonic growth of the two clinical strains were significantly enhanced (P<0.001) with gradually increased concentrations of HNP-1. None of the planktonic growth results of the 3 strains incubated with the scrambled HNP-1 was statistically significant. HNP-1 decreased the biofilm formation of the two clinical strains, AHN 9910 and 9508, significantly (P<0.01 and P<0.001; respectively). Conclusions: The present in vitro study demonstrates that F. nucleatum has the ability to withstand the lethal effects of HNP-1 even at concentrations simulating the diseased periodontium in vivo. The increase in planktonic growth could act as defense mechanisms of F. nucleatum against HNP-1.

Transmission oflight through individually formed fiber- reinforced composite post (Yksilöllisesti muotoillun kuitukomposiittinastan valonläpäisevyys)

Kuitukomposiitista valmistettuja juurikanavanastoja käytetään apuna, kun restauroidaan juurihoidettuja ja kruunuosastaan runsaasti kudosta menettäneitä hampaita. Kliinisen kestävyyden kannalta on tärkeää että nasta kiinnittyy hampaaseen hyvin. Tarvittavan valomäärän saattaminen valokovetuksella pimeään juurikanavaan on vaikeaa ja sen vuoksi nastojen kiinnittämiseen suositellaan kaksoiskovetteista yhdistelmämuovisementtiä, joka kovettuu vain osittain valolla. Jotta nasta ja sementti polymeroituisivat hyvin, nastan hyvä valonläpäisy- ja sirontakyky olisi eduksi. Tehdasvalmisteisten nastojen valonläpäisykyvyn on todettu heikkenevän niiden pituuden kasvaessa. Yksilöllisesti muotoilluilla kuitukomposiittinastoilla, joilla on osittaislomittaismuoviverkostorakenne (semi-IPN) polymeerimatriisi, on todettu tehdasvalmisteisia kuitunastoja parempi sidos nastan ja yhdistelmämuovisementin välillä. Yksilöllisesti muotoilluilla kuitunastoilla näyttäisi myös olevan hyvä valonjohtamiskyky, mutta lisätutkimuksia tarvitaan. Tässä tutkimuksessa selvitettiin yksilöllisesti muotoillun kuitukomposiittinastan (EverStick Post) ja kahden tehdasvalmisteisen (Relyx Fiber Post ja GC Fiber Post) kuitukomposiittina stan valonläpäisevyyttä sekä pituuden vaikutusta niiden valonläpäisykykyyn laboratorio- olosuhteissa. Tutkimushypoteesi oli, että nastojen valonläpäisykyky heikkenee niiden pidentyessä. Tutkimuksessa kaikista nastatyypeistä valmistettiin eripituisia nastoja (4, 8, 12 ja 16 mm). Nastoille tehtiin samanpituiset testikappaleet muoviputkesta ja polyvinyylisiloksaanista, ja nastat asetettiin niiden sisään. Tämän jälkeen nastoja kovetettiin valokovettimella 10 sekuntia, ja läpi päässyt valo mitattiin MARC Resin Calibrator -laitteella. Kontrollina käytettiin tyhjää testikappaletta ilman nastaa. Keskeiseksi tulokseksi saatiin, että yksilöllisesti muotoillulla kuitukomposiittinastalla oli kaikissa pituusryhmissä muita nastoja merkitsevästi parempi valonläpäisykyky. Tulokset osoittivat myös, että kaikkien nastojen valonläpäisevyys laski merkitsevästi nastan pituuden lisääntyessä aina 12 millimetriin asti. Tulosten perusteella yksilöllisesti muotoillulla kuitukomposiittinastalla on tehdasvalmisteista nastaa parempi valonläpäisykyky. Kuitukomposiittinastojen valonläpäisykyky heikkenee niiden pituuden kasvaessa aiempien tutkimusten mukaisesti. Jatkotutkimuksissa tulisi selvittää, miten valonläpäisevyys ja siroaminen vaikuttavat nastan ja sementin polymeroitumiseen ja siten kliiniseen lopputulokseen.

Design of traction transmission and suspension systems for an omni-directional mobile robot

This project aims to design and manufacture a mobile robot with two Universal Robot UR10 mainly used indoors. In order to obtain omni-directional maneuverability, the mobile robot is constructed with Mecanum wheels. The Mecanum wheel can move in any direction with a series of rollers attached to itself. These rollers are angled at 45º about the hub’s circumference. This type of wheels can be used in both driving and steering with their any-direction property. This paper is focused on the design of traction system and suspension system, and the velocity control of Mecanum wheels in the close-loop control system. The mechanical design includes selection of bearing housing, couplers which are act as connection between shafts, motor parts, and other needed components. The 3D design software SolidWorks is utilized to assemble all the components in order to get correct tolerance. The driving shaft is designed based on assembled structure via the software as well. The design of suspension system is to compensate the assembly error of Mecanum wheels to guarantee the stability of the robot. The control system of motor drivers is realized through the Robot Operating System (ROS) on Ubuntu Linux. The purpose of inverse kinematics is to obtain the relationship among the movements of all Mecanum wheels. Via programming and interacting with the computer, the robot could move with required speed and direction.