Pienen ja keskisuuren osakeyhtiön pääoma uudessa osakeyhtiölaissa

Tämä Pro Gradu tutkielman tavoitteena on selvittää, miten 1.9.2007 voimaan tullut uusi osakeyhtiölaki vaikuttaa pienten ja keskisuurten osakeyhtiöiden pääomanhallintaan. Vastausta etsitään myös siihen, toteutuivatko lakimuutoksessa asetetut tavoitteet pienen ja keskisuuren yrityksen näkökulmasta. Tutkimusmetodologiana käytetään käsiteanalyyttistä lähestymistapaa. Tutkielma on havainnoiva ja selittävä. Tutkimuksen analyysin lähteenä käytettävät yritystilanteet ovat kirjoittajan tilitoimistotyössä esiin tulleita. Lain kokonaisuudistuksessa eräs tavoite oli tehdä laista pienille osakeyhtiöille selkeä ja toimintaa helpottava. Lain teksti on helppolukuisempaa ja lain rakenne on selkeä. Etua monelle perustettavalle pienelle osakeyhtiölle on siitä, että perustaminen on yksinkertaistunut ja minimipääoma pienentynyt. Velkojien aseman parantamiseksi lakiin otetun maksukykyisyystestin ja joustavan rahoitusratkaisun tarjoavan sijoitetun vapaan pääoman rahaston voidaan myös katsoa auttavan pientä ja keskisuurta osakeyhtiötä toiminnassaan. Maksukykyisyystesti on hyödyllinen muistutus varovaisesta varojen jaosta ja SVOP rahasto on vaihtoehto pääomalainalle. Verolakien uudistamatta jääminen osakeyhtiölain muuttuessa on vaikeuttanut joidenkin OYL:n mahdollistamien uusien menettelytapojen käyttöönottoa.

Design and manufacture of a microdistillation column

Aim of this thesis was to design and manufacture a microdistillation column. The literature review part of this thesis covers stainless steels, material processing and basics about engineering design and distillation. The main focus, however, is on the experimental part. Experimental part is divided into five distinct sections: First part is where the device is introduced and separated into three parts. Secondly the device is designed part by part. It consists mostly of detail problem solving, since the first drawings had already been drawn and the critical dimensions decided. Third part is the manufacture, which was not fully completed since the final assembly was left out of this thesis. Fourth part is the test welding for the device, and its analysis. Finally some ideas for further studies are presented. The main goal of this thesis was accomplished. The device only lacks some final assembly but otherwise it is complete. One thing that became clear during the process was how difficult it is to produce small and precise steel parts with conventional manufacturing methods. Internal stresses within steel plates and thermal distortions can easily ruin small steel structures. Designing appropriate welding jigs is an important task for even simple devices. Laser material processing is a promising tool for this kind of steel processing because of the flexibility, good cutting quality and also precise and low heat input when welding. Next step in this project is the final assembly and the actual distillation tests. The tests will be carried out at Helsinki University of Technology.

Conservation Genetics of Exploited Finnish Salmonid Fishes

Genetic diversity is one of the levels of biodiversity that the World Conservation Union (IUCN) has recognized as being important to preserve. This is because genetic diversity is fundamental to the future evolution and to the adaptive flexibility of a species to respond to the inherently dynamic nature of the natural world. Therefore, the key to maintaining biodiversity and healthy ecosystems is to identify, monitor and maintain locally-adapted populations, along with their unique gene pools, upon which future adaptation depends. Thus, conservation genetics deals with the genetic factors that affect extinction risk and the genetic management regimes required to minimize the risk. The conservation of exploited species, such as salmonid fishes, is particularly challenging due to the conflicts between different interest groups. In this thesis, I conduct a series of conservation genetic studies on primarily Finnish populations of two salmonid fish species (European grayling, Thymallus thymallus, and lake-run brown trout, Salmo trutta) which are popular recreational game fishes in Finland. The general aim of these studies was to apply and develop population genetic approaches to assist conservation and sustainable harvest of these populations. The approaches applied included: i) the characterization of population genetic structure at national and local scales; ii) the identification of management units and the prioritization of populations for conservation based on evolutionary forces shaping indigenous gene pools; iii) the detection of population declines and the testing of the assumptions underlying these tests; and iv) the evaluation of the contribution of natural populations to a mixed stock fishery. Based on microsatellite analyses, clear genetic structuring of exploited Finnish grayling and brown trout populations was detected at both national and local scales. Finnish grayling were clustered into three genetically distinct groups, corresponding to northern, Baltic and south-eastern geographic areas of Finland. The genetic differentiation among and within population groups of grayling ranged from moderate to high levels. Such strong genetic structuring combined with low genetic diversity strongly indicates that genetic drift plays a major role in the evolution of grayling populations. Further analyses of European grayling covering the majority of the species’ distribution range indicated a strong global footprint of population decline. Using a coalescent approach the beginning of population reduction was dated back to 1 000-10 000 years ago (ca. 200-2 000 generations). Forward simulations demonstrated that the bottleneck footprints measured using the M ratio can persist within small populations much longer than previously anticipated in the face of low levels of gene flow. In contrast to the M ratio, two alternative methods for genetic bottleneck detection identified recent bottlenecks in six grayling populations that warrant future monitoring. Consistent with the predominant role of random genetic drift, the effective population size (N_e) estimates of all grayling populations were very low with the majority of N_e estimates below 50. Taken together, highly structured local populations, limited gene flow and the small N_e of grayling populations indicates that grayling populations are vulnerable to overexploitation and, hence, monitoring and careful management using the precautionary principles is required not only in Finland but throughout Europe. Population genetic analyses of lake-run brown trout populations in the Inari basin (northernmost Finland) revealed hierarchical population structure where individual populations were clustered into three population groups largely corresponding to different geographic regions of the basin. Similar to my earlier work with European grayling, the genetic differentiation among and within population groups of lake-run brown trout was relatively high. Such strong differentiation indicated that the power to determine the relative contribution of populations in mixed fisheries should be relatively high. Consistent with these expectations, high accuracy and precision in mixed stock analysis (MSA) simulations were observed. Application of MSA to indigenous fish caught in the Inari basin identified altogether twelve populations that contributed significantly to mixed stock fisheries with the Ivalojoki river system being the major contributor (70%) to the total catch. When the contribution of wild trout populations to the fisheries was evaluated regionally, geographically nearby populations were the main contributors to the local catches. MSA also revealed a clear separation between the lower and upper reaches of Ivalojoki river system – in contrast to lower reaches of the Ivalojoki river that contributed considerably to the catch, populations from the upper reaches of the Ivalojoki river system (>140 km from the river mouth) did not contribute significantly to the fishery. This could be related to the available habitat size but also associated with a resident type life history and increased cost of migration. The studies in my thesis highlight the importance of dense sampling and wide population coverage at the scale being studied and also demonstrate the importance of critical evaluation of the underlying assumptions of the population genetic models and methods used. These results have important implications for conservation and sustainable fisheries management of Finnish populations of European grayling and brown trout in the Inari basin.

Use of neural networks in robot positioning of large flexible redundant manipulators

Deflection compensation of flexible boom structures in robot positioning is usually done using tables containing the magnitude of the deflection with inverse kinematics solutions of a rigid structure. The number of table values increases greatly if the working area of the boom is large and the required positioning accuracy is high. The inverse kinematics problems are very nonlinear, and if the structure is redundant, in some cases it cannot be solved in a closed form. If the structural flexibility of the manipulator arms is taken into account, the problem is almost impossible to solve using analytical methods. Neural networks offer a possibility to approximate any linear or nonlinear function. This study presents four different methods of using neural networks in the static deflection compensation and inverse kinematics solution of a flexible hydraulically driven manipulator. The training information required for training neural networks is obtained by employing a simulation model that includes elasticity characteristics. The functionality of the presented methods is tested based on the simulated and measured results of positioning accuracy. The simulated positioning accuracy is tested in 25 separate coordinate points. For each point, the positioning is tested with five different mass loads. The mean positioning error of a manipulator decreased from 31.9 mm to 4.1 mm in the test points. This accuracy enables the use of flexible manipulators in the positioning of larger objects. The measured positioning accuracy is tested in 9 separate points using three different mass loads. The mean positioning error decreased from 10.6 mm to 4.7 mm and the maximum error from 27.5 mm to 11.0 mm.

Ikääntyvät työelämässä. Päihittääkö nuoruus ja koulutus aikuisuuden ja kokemuksen?

The Ageing in Working Life. Do Adolescence and Schooling Beat Adulthood and Experience? This study examines the changes in the work and the work organisations of employees in the fields of health care and retail trade who have turned 45 and their experience of change. In addition, the question of how ageing employees experience their status in post-modern working life is explored. Attention is also focused on the choices and decisions connected with staying at work and retiring. These views are examined in relation to professions and professional cultures. Thematic interviews (N=98) were used to gather the material. The effects of the market liberalistic turn in welfare policy are clearly seen in the everyday work of the health care professions. These changes were examined from the point of view of managing by outcomes and quality assurance, multi-professional cooperation, flexibility in the division of labour, and the spread of market-like procedures. The discourse of those in involved retail trade was dominated by extremely tight global market competition and control of outcomes, and by the structural changes taking place in the retail trade sector. This change discourse was to a large extent a reaction to those changes in the functional environment which were experienced as negative and to the conflict between their own professional identity and professional ethics on the one hand, and their functional environment on the other. There were also obstacles connected with professional culture: defending one's own station and power, guarding the 'frontier', showed up in attitudes towards new management and organisation models or towards structural and functional reforms. The deep structures of professional culture and the mindset of the actors change much more slowly than the functional practices of organisations. For those in a supervisory position, the loss of power due to becoming part of a chain or because of the introduction of a team organisation model was not an easy thing to accept. The nurses and others in related fields felt that they were forced to do work that was below their level of training and professional skill. For sales personnel and those who did assisting work in health care, power and the possibility of having an influence were not so important, as long as they were able to do their work in their own way and were trusted. This view is often completely forgotten, for example, in various organisation models in which power and the possibility of having an influence entwined with power are taken for granted as being clearly positive and desired aspects of job satisfaction. Up to date professional skills were experienced as being important from the point of view of professional identity and self-worth. Thus, training can be understood as a moral obligation, which in turn is intertwined with professional ideology. In the rhetoric of adult education, an adult is expected to be an active player who will seek training again and again if working life so requires. The dark side of this ideology, which leads to feelings of guilt, was apparent in the thoughts of the respondents. Am I never good enough at my job; why must I continually strive for better, additional qualifications? The majority of the respondents evaluated their expertise as being at quite a high level. This self-confidence did not extend to applying for a job. Job recruitment was seen as a situation in which age discrimination reached its peak. The interviewees were unanimous about the idea that society favours the young. Especially among those in the retail trade sector, there was a feeling that it would be difficult, if not impossible, to find a new job of the same level or a permanent post if they were made redundant. Age discrimination was also apparent in the retail trade field in the form of older employees being retired against their will or transferred to other tasks. It was felt that ruthless forced retirement of older workers was part of the personnel policy of some organisations. The importance of one's outward appearance was connected with the theme of discrimination. This phenomenon is described using the concept of the double standard of ageing in feminist research. An ageing woman is relegated to an inferior position due to both her age and her sex. A culture that would both make possible and allow various types of choices regardless of age, which is described as being characteristic of the post-modern era, does not seem to be very topical in the practice of working life. It is important for employees that the management and the personnel policy that is being implemented makes them feel like both their contribution and they as individuals are appreciated, that their opinions are listened to and that they are noticed as persons. The interviewees hoped for gratitude and a concern for the well-being of employees that shows in everyday life. They valued training and activities aimed at maintaining their work ability, but thought that better coping at work and a pleasant working environment cannot be achieved through such measures as along as the foundation is 'in a mess'. Development of the quality of working life is the only thing that can improve job satisfaction and get people to remain in the work force longer than at present. There should be a sufficient number of properly trained employees at the work place. It was important to the respondents that they be able to stay on their job to the end with honour, since compromising with their own quality standards or acting contrary to their ideal self-image in terms of professional ethics would strike a blow to their professional self-esteem. They called for the development of various types of workplace flexibility, and felt that they have the right to a lightened workload and to early retirement. Early retirement was even seen as an altruistic deed: it would free up a place for younger workers. Thoughts of retirements were explained by familiar factors such as health and finances, life situation, the enticement of free-time, as well as by various factors related to work. It is very important to ageing employees that their work has meaningful content. The values related to self-fulfilment are felt to be of great importance, and if they cannot be realised at work, the respondents wanted more free time, either through retirement or in the form of flexibility in working life.

Kirjallisuutta

Kirjallisuusarvostelu

Kunnallisen tai seudullisen toimitilahallinnon yhtiöittämisen edut ja haitat

Tutkimuksen aihe liittyy kunnallisten toimitilojen yhtiöittämiskysymykseen, joka on ollut esillä monissa kunnissa useita vuosia ja laajentunut nyt seudulliseksi. Tutkimuksen tavoitteena on tarkastella, mitä hyötyä tai haittaa kunnallisen tai seudullisen toimitilahallinnosta vastaavan yksikön yhtiöittämisestä olisi. Parantaakseen tuottavuutta kunta voi järjestää toimintansa perinteisen kunnallisen organisoinnin sijaan liikelaitoksena tai osakeyhtiönä silloin, kun toiminnan laatu on liiketoiminnan luonteista. Suurin osa kuntien toimitilakiinteistöistä toimii kuntien palvelutuotannon suoranaisena tuotantovälineenä. Kuntien välisen yhteistoiminnan lisääminen voidaan nähdä mahdollisuutena julkisella sektorilla. Sen lisääminen edesauttaa tuottavuuden kasvua ja mahdollistaa palvelujen jatkuvan kehittämisen. Yhtiöittäminen tuo toimintaan mukaan asioita, jotka varmasti tehostavat toimintaa, kuten päätöksenteon nopeutuminen, toiminnan joustavuus, joustava ja kilpailukykyinen henkilöstöhallinto sekä yhtiön toiminnan ja päätösten ei-julkisuus jne. Huonoja puolia yhtiöittämisessä on kuntien kiinteistömenojen mahdollinen nousu käyttötalouspuolella sekä se, että yhtiöllä olisi käytännössä vain muutama asiakas. Suomessa kuntien toimitilahallinto on todennäköisesti menossa kohti yhtiömallia. Vaihtoehtoina yhtiöittämiselle ovat siis liikelaitosmallin kehittäminen ja joissain tapauksissa keskinäinen kiinteistöyhtiömalli. Joka tapauksessa kuntien toimitilahallintoyksiköiden toimintaa ja toimintamallia pitää kehittää, jotta niiden tuottavuus kasvaa sekä toiminta säilyy kannattavana ja järkevänä. Ulkoisten tekijöiden vaikutus kuntien toimitilahallinnon toimintaan kasvaa koko ajan.

Supply chain costs of a small board lot: sheet cutting and logistics

Succeeding in small board lot (0-20 tons) deliveries, is not always prosperous and failures as well as extra costs compared to standard costs arise. Failure deliveries from converting plants to customer locations tie a lot of unwanted and unexpected costs. Extra costs are handled as quality costs and more precise, internal failure costs. These costs revolve from unsuccessful truck payloads, redundant warehousing or unfavorable routing as examples. Quality costs are becoming more and more important factor in company’s financial decision making. Actual, realized truck payload correlates with the extra costs occurring, so filling the truck payload all get-out well is a key to lower the extra costs. Case company in this study is Corporation A, business segment Boards. Boards have outsourced half of their converting in order to gain better customer service via flexibility, lead time reductions and logistics efficiency improvements. Examination period of the study is first two quarters of year 2008 and deliveries examined are from converters to the customer locations. In Corporation A’s case, the total loss in failure deliveries is hundreds of thousands of Euros during the examination period. So, the logistics goal of getting the right product to the right place and right time for the least cost, does not completely realize.

Koneinvestoinnin suunnittelu valmistavaan teollisuuteen

Tämän diplomityön tavoitteena oli tutustua ohutlevyjen nykyaikaisiin koneellisiin leikkausmenetelmiin ja tutkia niiden soveltuvuutta yrityksen tarpeisiin. Kohdeyrityksessä investoinnin tarve jakautui tuottavuusinvestoinnin, korvausinvestoinnin ja strategisen investoinnin kesken. Tavoitteena oli luoda investointipolku, jonka avulla poissuljettiin menetelmät, jotka eivät soveltuneet yrityksen tuotantoon. Työn kirjallisuusosuudessa tarkastellaan teoriatietoja, jotka liittyvät yleisesti nykyaikaisiin ohutlevyjen leikkausmenetelmiin sekä investointiprojektin suunnitteluun ja toteutuksen teoriaan. Lisäksi käsitellään investointeihin liittyviä kannattavuus- ja kustannuslaskennan perusperiaatteita. Työn empiirisessä osassa selvitettiin yrityksen ohutlevyosien valmistuksen periaatteita nykytila-analyysin avulla. Tämän perusteella määritettiin nykyaikaisista markkinoilla olevista menetelmistä yritykselle soveltuvin. Tutkimuksen perusteella laserleikkaus oli menetelmistä soveltuvin. Perusinvestoinniltaan laser oli vaihtoehtoisista menetelmistä kallein, mutta se soveltui käytettävyyden, tehokkuuden, joustavuuden ja muiden ominaisuuksiensa perusteella parhaiten tuotannon tarpeisiin. Työn merkittävimmät tulokset osoittivat, että investoinnin kannattavuus riippui koneelle saatavasta käyttösuhteesta. Uusien koneiden tehokkuus lyhentäisi tuotannon läpimenoaikoja, mutta ilman riittävää kapasiteetin käyttöastetta kappaleiden omakustannusarvo nousisi. Lopputulokset ja suositukset on esitetty työn lopussa.

Sustaining competitive advantage in changing environment: Case small and medium sized sawmills

The aim of this study is to examine how small and medium sized (SME) sawmills sustain their competitive advantage in the changing environment. Firstly, this study researches what changes affect SME sawmills’ competitiveness and what factors construct their competitive advantage. Secondly, this study examines how SME sawmills sustain their competitive advantage in the future and how agile and flexible they are. The theoretical part of this study represents the existing literature related to changes and competitive advantage in changing situations. The empirical part was executed as a qualitative research and it consists of thematic interviews with two SME sawmills. The results of the study indicate that several change factors affect the competitiveness of SME sawmills and therefore it is crucial to be alert on them. SME sawmills sustain their competitive advantage in the future by specialization and by being agile.

Tuotekustannuslaskennan kehittäminen leipomoyrityksessä

Tutkimus käsittelee tuotekustannuslaskennan kehittämistä VAASAN Oy:ssä, joka on yksi johtavista leipomoyrityksistä Suomessa ja Baltiassa. Työn tavoitteena on kehittää tuotekustannuslaskentaa paremmin päätöksentekoa tukevaksi. Kehitystyössä otettiin huomioon laskentamallin joustavuuden säilyminen. Kehitystarpeet selvitettiin tuotekustannuslaskennan nykytilaanalyysillä sekä käyttäjäryhmien tietotarvekartoituksella. Kehityksen ohjaamiseen sovellettiin kustannustiedon laadukkuuden teorioita sekä riskienhallinnan työkalua. Lähtökohtana oli varsin hajautetusti toteutettu tuotekustannuslaskenta, minkä luotettavuuden ongelma tiedostettiin. Työn päätteeksi tuotekustannuslaskenta keskitetään. Keskittämisen tuoma tilaisuus halutaan käyttää mahdollisimman tehokkaasti hyödyksi kustannuslaskennan kehittämisessä. Ennen keskittämistä tulee tuotekustannuslaskenta johdonmukaistaa eri leipomoiden välillä. Tässä työssä kartoitettiin kehityskohteet sekä esitetään toimintamalli tai –ehdotus tärkeimpien kehityskohteiden ratkaisemiseksi. Tärkeimmät kehityskohteet löydettiin jäsentämällä ja priorisoimalla kehityskohteet. Tuotekustannuslaskentaa kehitettiin paremmin päätöksentekoa tukevaksi, johdonmukaisemmaksi, luotettavammaksi sekä sen käytettävyyttä kehitettiin.

Distributed ControlArchitecture of Power Electronics Building-Block-Based Frequency Converters

The increasing power demand and emerging applications drive the design of electrical power converters into modularization. Despite the wide use of modularized power stage structures, the control schemes that are used are often traditional, in other words, centralized. The flexibility and re-usability of these controllers are typically poor. With a dedicated distributed control scheme, the flexibility and re-usability of the system parts, building blocks, can be increased. Only a few distributed control schemes have been introduced for this purpose, but their breakthrough has not yet taken place. A demand for the further development offlexible control schemes for building-block-based applications clearly exists. The control topology, communication, synchronization, and functionality allocationaspects of building-block-based converters are studied in this doctoral thesis. A distributed control scheme that can be easily adapted to building-block-based power converter designs is developed. The example applications are a parallel and series connection of building blocks. The building block that is used in the implementations of both the applications is a commercial off-the-shelf two-level three-phase frequency converter with a custom-designed controller card. The major challenge with the parallel connection of power stages is the synchronization of the building blocks. The effect of synchronization accuracy on the system performance is studied. The functionality allocation and control scheme design are challenging in the seriesconnected multilevel converters, mainly because of the large number of modules. Various multilevel modulation schemes are analyzed with respect to the implementation, and this information is used to develop a flexible control scheme for modular multilevel inverters.

Modulaarinen kiinnitintekniikka alumiiniveneiden robottihitsauksessa

Tällä hetkellä hitsauksen automatisointiaste on hyvin pieni alumiinivenevalmistuksessa. Automatisointiasteen kasvattaminen on ensiarvoisen tärkeää kilpailukyvyn säilyttämiseksi, sekä edelleen nostamiseksi. Automatisointiasteen kasvattamisen esteenä ei ole teknologian puute, vaan suunnitellut tuotteet soveltuvat huonosti robotisoituun hitsaukseen. Lisäksi liitettävien osien tarkkuus on monissa tapauksissa puutteellinen, joten robottihitsaus on monessa tapauksessa mahdotonta. Robottihitsauksessa vaaditaan osien hyvää paikoittamista ja siihen tarvitaan kiinnittimiä. Kuitenkin alumiinivenevalmistuksessa valmistusmäärät ovat sen verran pieniä, että tuotekohtaisia kiinnittimiä ei kannata hankkia tai valmistaa. Siksi kiinnittimiltä vaaditaan joustavuutta ja modulaarisuutta, jotta samalla kiinnittimellä voi hitsata useita vastaavia piirteitä omaavia tuotteita. Tässä työssä tutkittiin modulaarisia kiinnittimiä, edistyneitä kiinnitinsuunnitteluprosesseja, osavalmistustarkkuuksia, tuotemoduloinnin hyödyntämistä ja alumiinin robottihitsauksen erityispiirteitä. Työssä suunniteltiin ja simuloitiin modulaarinen hitsauskiinnitin, jota käytetään tietyn alumiinivenemallin erillisenä osakokoonpanona valmistettavan jäykisterakennekonseptin hitsaamiseen. Suunnittelu ja simulointi tehtiin Delmia V5R20 -ohjelmistolla. Jäykisterakenne on modulaarinen tuoterakenne, jossa käytetään itsepaikoittavia liitoksia helpottamaan osien asettelua ja yksinkertaistamaan kiinnitintä. Kiinnitin soveltuu joustavasti erikokoisten jäykisterakenneosakokoonpanojen valmistukseen. Lisäksi suunniteltua kiinnitintä verrattiin kaupalliseen modulaariseen Demmeler -kiinnitinjärjestelmään. Jäykisterakenteen osakokoonpanon hitsaaminen robotilla lyhentää valmistusaikaa verrattuna nykytilaan, kun osat voidaan asettaa kiinnittimeen nopeasti ja luotettavasti. Samalla jäykisterakenteen tekeminen erillisenä osakokoonpanona lyhentää veneen rungon loppukokoonpanoaikaa ja mahdollistaa hitsausrobotin käytön myös veneen muiden hitsien hitsaamisessa. Modulaarisilla hitsauskiinnittimillä saavutetaan alumiiniveneiden nykyisillä valmistusmäärillä skaalaetuja, joita tuotekohtaisella kiinnittimellä ei voi saavuttaa.

Boundary identification in the domain of a parabolic partial differential equation

Bakgrunden och inspirationen till föreliggande studie är tidigare forskning i tillämpningar på randidentifiering i metallindustrin. Effektiv randidentifiering möjliggör mindre säkerhetsmarginaler och längre serviceintervall för apparaturen i industriella högtemperaturprocesser, utan ökad risk för materielhaverier. I idealfallet vore en metod för randidentifiering baserad på uppföljning av någon indirekt variabel som kan mätas rutinmässigt eller till en ringa kostnad. En dylik variabel för smältugnar är temperaturen i olika positioner i väggen. Denna kan utnyttjas som insignal till en randidentifieringsmetod för att övervaka ugnens väggtjocklek. Vi ger en bakgrund och motivering till valet av den geometriskt endimensionella dynamiska modellen för randidentifiering, som diskuteras i arbetets senare del, framom en flerdimensionell geometrisk beskrivning. I de aktuella industriella tillämpningarna är dynamiken samt fördelarna med en enkel modellstruktur viktigare än exakt geometrisk beskrivning. Lösningsmetoder för den s.k. sidledes värmeledningsekvationen har många saker gemensamt med randidentifiering. Därför studerar vi egenskaper hos lösningarna till denna ekvation, inverkan av mätfel och något som brukar kallas förorening av mätbrus, regularisering och allmännare följder av icke-välställdheten hos sidledes värmeledningsekvationen. Vi studerar en uppsättning av tre olika metoder för randidentifiering, av vilka de två första är utvecklade från en strikt matematisk och den tredje från en mera tillämpad utgångspunkt. Metoderna har olika egenskaper med specifika fördelar och nackdelar. De rent matematiskt baserade metoderna karakteriseras av god noggrannhet och låg numerisk kostnad, dock till priset av låg flexibilitet i formuleringen av den modellbeskrivande partiella differentialekvationen. Den tredje, mera tillämpade, metoden kännetecknas av en sämre noggrannhet förorsakad av en högre grad av icke-välställdhet hos den mera flexibla modellen. För denna gjordes även en ansats till feluppskattning, som senare kunde observeras överensstämma med praktiska beräkningar med metoden. Studien kan anses vara en god startpunkt och matematisk bas för utveckling av industriella tillämpningar av randidentifiering, speciellt mot hantering av olinjära och diskontinuerliga materialegenskaper och plötsliga förändringar orsakade av “nedfallande” väggmaterial. Med de behandlade metoderna förefaller det möjligt att uppnå en robust, snabb och tillräckligt noggrann metod av begränsad komplexitet för randidentifiering.

Neural correlates of language learning in adults

The human language-learning ability persists throughout life, indicating considerable flexibility at the cognitive and neural level. This ability spans from expanding the vocabulary in the mother tongue to acquisition of a new language with its lexicon and grammar. The present thesis consists of five studies that tap both of these aspects of adult language learning by using magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) during language processing and language learning tasks. The thesis shows that learning novel phonological word forms, either in the native tongue or when exposed to a foreign phonology, activates the brain in similar ways. The results also show that novel native words readily become integrated in the mental lexicon. Several studies in the thesis highlight the left temporal cortex as an important brain region in learning and accessing phonological forms. Incidental learning of foreign phonological word forms was reflected in functionally distinct temporal lobe areas that, respectively, reflected short-term memory processes and more stable learning that persisted to the next day. In a study where explicitly trained items were tracked for ten months, it was found that enhanced naming-related temporal and frontal activation one week after learning was predictive of good long-term memory. The results suggest that memory maintenance is an active process that depends on mechanisms of reconsolidation, and that these process vary considerably between individuals. The thesis put special emphasis on studying language learning in the context of language production. The neural foundation of language production has been studied considerably less than that of perceptive language, especially on the sentence level. A well-known paradigm in language production studies is picture naming, also used as a clinical tool in neuropsychology. This thesis shows that accessing the meaning and phonological form of a depicted object are subserved by different neural implementations. Moreover, a comparison between action and object naming from identical images indicated that the grammatical class of the retrieved word (verb, noun) is less important than the visual content of the image. In the present thesis, the picture naming was further modified into a novel paradigm in order to probe sentence-level speech production in a newly learned miniature language. Neural activity related to grammatical processing did not differ between the novel language and the mother tongue, but stronger neural activation for the novel language was observed during the planning of the upcoming output, likely related to more demanding lexical retrieval and short-term memory. In sum, the thesis aimed at examining language learning by combining different linguistic domains, such as phonology, semantics, and grammar, in a dynamic description of language processing in the human brain.