Impersonal trust within the organization: what, how and why?

It has been shown in organizational settings that trust is a crucial factor in different kinds of outcomes, and consequently, building employee trust in the employer is a goal for all kinds of organizations. Although it is recognized that trust in organizations operates on multiple levels, at present there is no clear consensus on the concept of trust within the organization. One can have trust in particular people (i.e. interpersonal trust) or in organized systems (i.e. impersonal trust). Until recently organizational trust has been treated mainly as an interpersonal phenomenon. However, the interpersonal approach is limited. Scholars studying organizational trust have thus far focused only on specific dimensions of impersonal trust, and none have taken a comprehensive approach. The first objective in this study was to develop a construct and a scale encompassing the impersonal element of organizational trust. The second objective was to examine the effects of various HRM practices on the impersonal dimensions of organizational trust. Moreover, although the “black box” model of HRM is widely studied, there have been only a few attempts to unlock the box. Previous studies on the HRM-performance link refer to trust, and this work contributes to the literature in considering trust an impersonal issue in the relationship between HRM, trust, and performance. The third objective was thus to clarify the role of impersonal trust in the relationship between HRM and performance. The study is divided into two parts comprising the Introduction and four separate publications. Each publication addresses a distinct sub-question, whereas the Introduction discusses the overall results in the light of the individual sub-questions. The study makes two major contributions to the research on trust. Firstly, it offers a framework describing the construct of impersonal trust, which to date has not been clearly articulated in the research on organizational trust. Secondly, a comprehensive, psychometrically sound, operationally valid scale for measuring impersonal trust was developed. In addition, the study makes an empirical contribution to the research on strategic HRM. First, it shows that HRM practices affect impersonal trust and the contribution is to consider the HRM-trust link in terms of impersonal organizational trust. It is shown that each of the six HRM practices in focus is connected to impersonal trust. A further contribution lies in unlocking the black box. The study explores the impersonal element of organizational trust and its mediating role between HRM practices and performance. The result is the identification of the path by which HRM contributes to performance through the mediator of impersonal trust. It is shown that the effect on performance of HRM designed specifically to enhance employees’ impersonal trust in the organization is positive.

Objective Evaluation of Nasal Dimensions in Children with Acoustic Rhinometry

Aims: This study was carried out to investigate the usefulness of acoustic rhinometry in the evaluation of intranasal dimensions in children. The aim was to define reference values for school children. In addition, the role of the VAS scale in the subjective evaluation of nasal obstruction in children was studied. Materials and methods: Measurements were done with Acoustic Rhinometry A1. The values of special interest were the minimal cross-sectional area (MCA) and the anterior volume of the nose (VOL). The data for reference values included 124 voluntary school children with no permanent nasal symptoms, aged between 7 and 14 years. Data were collected at baseline and after decongestion of the nose; the VAS scale was filled in before measurements. The subjects in the follow-up study (n=74, age between 1 and 12 years) were receiving intranasal spray of insulin or placebo. The nasal symptoms were recorded and acoustic rhinometry was measured at each control visit. Results: In school children, the mean total MCA was 0.752 cm2 (SD 0.165), and the mean total VOL was 4.00 cm3 (SD 0.63) at baseline. After decongestion, a significant increase in the mean TMCA and in the mean TVOL was found. A correlation was found between TMCA and age, and between TVOL and height of a child. There was no difference between boys and girls. A correlation was found between unilateral acoustic values and VAS at baseline, but not after decongestion. No difference wasfound in acoustic values or symptoms between the insulin and placebo group in the follow-up study of two years. Conclusions: Acoustic rhinometry is a suitable objective method to examine intranasal dimensions in children. It is easy to perform and well tolerated. Reference values for children between 7 and 14 years were established.

Kuulla vai kuunnella – käyttäjää osallistavan palveluinnovoinnin lähestymistavan toteuttamisen haasteita julkisella sektorilla

Julkisen sektorin itsensä synnyttämien innovaatioiden ja innovoinnin näkökulma on verrattain tuore innovaatiotutkimuksen tutkimuskohde. Vielä uudempaa lähestymistapaa edustaa käyttäjälähtöinen ja käyttäjää osallistava palveluinnovaatiotutkimus julkisella sektorilla. Käyttäjälähtöisen ja käyttäjää osallistavan palveluinnovoinnin lähestymistavan toteuttamisesta ollaan kiinnostuneita, mutta tieteelliseen tutkimukseen perustuva tieto lähestymistavasta on vielä kohtuullisen niukkaa. Tämän käyttäjälähtöiseen palvelujen innovointiin keskittyvän väitöskirjatutkimuksen päätavoitteena on mikrotasolla tunnistaa ja ryhmitellä käyttäjää osallistavan palveluinnovoinnin lähestymistavan toteuttamisen haasteita julkisella sektorilla. Väitöskirjatutkimuksen alatavoitteena on tutkimuksesta saatavan tiedon avulla muodostaa kysymyslista tukemaan lähestymistavan käyttöönottamista ja toteuttamista julkisen sektorin palveluorganisaatioissa ja -verkostoissa. Julkisen palvelusektorin ohella väitöskirjan tutkimustuloksia voivat soveltuvin osin hyödyntää myös yksityisen ja kolmannen sektorin palveluorganisaatiot ja -verkostot sekä käyttäjälähtöisen innovaatiopolitiikan suunnitteluun ja sen jalkauttamiseen osallistuvat tahot. Haasteita lähestytään tutkimuksessa käyttäjälähtöisen ja käyttäjää osallistavan palveluinnovoinnin lähestymistavan piirteiden kautta ja haasteita tarkastellaan kehittäjäviranomaisten (ryhmätaso) näkökulmasta. Kuntasektori on valittu tutkimukseen edustamaan julkista sektoria. Lähestymistavan piirteiksi tutkimuksessa määritellään käyttäjänäkökulman ohjaava rooli organisaation innovaatiotoiminnan strategisella tasolla ja palvelujen uudistamisprosessien tasoilla, avoimuus (erityisesti käyttäjärajapinta) ja tulkinnallisuus innovaatioprosessien varhaisessa vaiheessa sekä laaja-alainen käsitys innovaatioiden lähteistä käyttäjänäkökulmaa muodostettaessa. Tutkimuksen kohteena on hyvinvointipalveluinnovaatioprosessien varhainen vaihe, jolloin keskeisessä asemassa on uusien ideoiden sekä uuden tiedon ja ymmärryksen hankinta hyödynnettäväksi innovaatioprosessien seuraavissa vaiheissa. Tutkimuksessa rajaudutaan käyttäjälähtöisen palveluinnovoinnin muotoon, jossa käyttäjät intentionaalisesti ja konkreettisesti osallistetaan kehittäjäviranomaisjohtoisiin palveluinnovaatioprosesseihin. Käyttäjiksi tutkimuksessa ymmärretään palvelun loppukäyttäjät palvelujen ”ulkoisina hyödyntäjinä” ja yli sektorialisten palveluprosessien henkilöstö palvelujen ”sisäisinä hyödyntäjinä”. Hyvinvointipalveluista tutkimuksessa ovat edustettuina sosiaali- ja terveyspalvelut sekä ikäihmisten palvelukeskusten tarjoamat palvelut. Kuntasektorin innovaatiotoiminnan kenttä ymmärretään tutkimuksessa verkostomaisena kokonaisuutena, joka ylittää kuntien hallinnolliset rajat. Artikkeliväitöskirjana toteutetun väitöskirjatutkimuksen metodologia perustuu usean tapauksen tapaustutkimukseen (multiple case-studies) ja kvalitatiiviseen tutkimusotteeseen. Työn empiirinen osuus koostuu viidestä artikkelina julkaistusta osatutkimuksesta. Osatutkimuksissa käytetään tapaustutkimuksen eri variaatioita, ja tutkimusaineistot on kerätty kolmesta eri perustutkimusympäristöstä. Osatutkimuksien tapaukset on valittu palvelun käyttäjien ”äänen jatkumon” (the voice of the customer) eri kohdista. Käyttäjän ääntä käytetään tutkimuksessa metodisena ratkaisuna ja metaforana. Lisäksi käyttäjän ääni ymmärretään tutkimuksessa paremminkin kollektiivisena ja laajemmista palvelujen kehittämisnäkökulmista kertovana tekijänä kuin yksittäisten palvelun käyttäjien tarpeista ja toiveista kertovana metaforana. Käyttäjää osallistavan palveluinnovoinnin lähestymistavan toteuttamisen haasteiksi julkisella sektorilla tutkimuksessa tunnistetaan viisi haastetta. Tiivistetysti haasteena on 1. palvelujen käyttäjien subjektiuteen perustuva käyttäjälähtöisyys palvelujen uudistamisessa 2. tunnistaa palvelun käyttäjät innovaatiotoiminnan voimavarana ja rohkaistua heidän osallistamiseensa 3. sitoutuminen yhteistoiminnallisuuteen käyttäjä- ja muita rajapintoja ylittävissä palvelujen uudistamisprosesseissa ja innovaatiohakuisuus työskentelyssä 4. oivaltaa palvelutoivelistoja ja asiakaspalautteita laajempia kehittämisnäkökulmia 5. synnyttää luottamukseen perustuva hyvä kierre palvelun käyttäjien ja kehittäjien välille. Tutkimustuloksena syntyneet haasteet paikannetaan tutkimuksessa käyttäjän äänen jatkumolle erilaisin painotuksin. Lisäksi tutkimustulosten pohjalta tehdään kolme keskeistä johtopäätöstä. Ensinnäkin palvelun kehittäjätahon sekä palvelun loppukäyttäjien ja palvelujen sisäisten hyödyntäjien väliltä on tunnistettavissa innovaatiopotentiaalia sisältäviä rakenteellisia aukkoja. Toiseksi kehittäjäviranomaistahon valmius ja halu laajentaa tiedonmuodostustaan palvelujen uudistamisessa palvelun käyttäjien kanssa yhteisöllisen tiedonmuodostuksen suuntaan on puutteellinen. Kolmanneksi palvelujen kehittäjätaho ei ole sisäistänyt riittävässä määrin käyttäjää osallistavan palveluinnovoinnin lähestymistavan metodologisia perusajatuksia. Tutkimuksessa tunnistetut viisi haastetta osoittavat, että käyttäjää osallistavan palveluinnovoinnin lähestymistavan käyttöönotto hyvinvointipalveluorganisaation tai -verkoston palvelujen innovoinnin lähestymistavaksi ei ole mekaaninen toimenpide. Lähestymistavan käyttöönottoa tukeva kysymyslista perustuu tutkimuksessa tunnistettuihin haasteisiin. Kysymyslista on laadittu siten, että kysymykset liittyvät laajasti julkisten palveluorganisaatioiden ja -verkostojen innovaatiokulttuuriin. Kaksiosaisen kysymyslistan ensimmäisen osan kysymykset käsittelevät innovointia ohjaavia mentaalisia malleja. Ensimmäisessä osassa esitetään esimerkiksi seuraava kysymys: ”Millaista käsitystäpalvelun käyttäjistä (kuntalaisista) sekä käyttäjien ja kehittäjien (viranomaisten) välisestä suhteesta ilmennämme palvelujen innovoinnissa; onko palvelujen käyttäjä (kuntalainen) kohde, jolle kehitetään palveluja, vai onko hän jopa välttämätön kehittämiskumppani?”. Kysymyslistan toisen osan kysymykset liittyvät innovaatiokäytänteisiin ja valmiuksiin. Esimerkkinä voidaan mainita seuraava kaksiosainen kysymys: ”Tukevatko innovaatiokäytänteemme käyttäjärajapinnan ylittäviä innovaatioprosesseja ja sitoudummeko avoimin mielin työskentelyyn palvelun käyttäjien, potentiaalisten käyttäjien tai ei-käyttäjien kanssa? Mitä hyötyjä koemme yhteistoiminnallisuudesta koituvan meille ja käyttäjille sekä innovaation laatuominaisuuksiin?”. Mitä tulee tutkimuksen otsikon alkuosaan ”kuulla vai kuunnella”, vastaus on, että pääpaino on sanalla ”kuulla”. Pohdintaluvussa tuodaan myös esille tarve – tai ainakin kriittisen tarkastelun tarve – käyttäjälähtöisen ja käyttäjää osallistavan palveluinnovoinnin käsitteen ja sen luonteen sekä tavoitteiden määrittelemiselle julkisen sektorin ominaispiirteistä käsin vastapainona alkuperältään yksityisen sektorin liiketoimintakontekstista lähtöisin oleville määrittelyille.

Combustion properties of biomass residues rich in phosphorus

Tillgången på traditionella biobränslen är begränsad och därför behöver man ta fram nya, tidigare outnyttjade biobränslen för att möta de uppställda CO2 emissionsmålen av EU och det ständigt ökande energibehovet. Under de senare åren har intresset riktats mot termisk energiutvinning ur olika restfraktioner och avfall. Vid produktion av fordonsbränsle ur biomassa är den fasta restprodukten ofta den största procesströmmen i produktionsanläggningen. En riktig hantering av restprodukterna skulle göra produktionen mera lönsam och mer ekologiskt hållbar. Ett alternativ är att genom förbränning producera elektricitet och/eller värme eftersom dessa restprodukter anses som CO2-neutrala. Målsättningen med den här avhandlingen var att studera förbränningsegenskaperna hos några fasta restprodukter som uppstår vid framställning av förnybara fordonsbränslen. De fyra undersökta materialen är rapskaka, palmkärnskaka, torkad drank och stabiliserat rötslam. I studien används ett stort urval av undersökningsmetoder, från laboratorieskala till fullskalig förbränning, för att identifiera de huvudsakliga utmaningarna förknippade med förbränning av restprodukterna i pannor med fluidiserad bäddteknik. Med hjälp av detaljerad bränslekarakterisering kunde restprodukterna konstateras vara en värdefull källa för värme- och elproduktion. Den kemiska sammansättningen av restprodukterna varierar stort jämfört med mera traditionellt använda biobränslen. En gemensam faktor för alla de studerade restprodukterna är en hög fosforhalt. På grund av de låga fosforkoncentrationerna i de traditionella biobränslena har grundämnet hittills inte ansetts spela någon större roll i askkemin. Experimenten visade nu att fosfor inte mera kan försummas då man studerar kemin i förbränningsprocesser, då allt flera fosforrika bränslen tränger in på energimarknaden.

Numerical evaluation of the modulus of longitudinal elasticity in structural round timber elements of the Eucalyptus genus

Currently, the standards that deal with the determination of the properties of rigidity and strength for structural round timber elements do not take in consideration in their calculations and mathematical models the influence of the existing irregularities in the geometry of these elements. This study has as objective to determine the effective value of the modulus of longitudinal elasticity for structural round timber pieces of the Eucalyptus citriodora genus by a technique of optimization allied to the Inverse Analysis Method, to the Finite Element Method and the Least Square Method.

Generalized Differential Evolution for Global Multi-Objective Optimization with Constraints

The objective of this thesis work is to develop and study the Differential Evolution Algorithm for multi-objective optimization with constraints. Differential Evolution is an evolutionary algorithm that has gained in popularity because of its simplicity and good observed performance. Multi-objective evolutionary algorithms have become popular since they are able to produce a set of compromise solutions during the search process to approximate the Pareto-optimal front. The starting point for this thesis was an idea how Differential Evolution, with simple changes, could be extended for optimization with multiple constraints and objectives. This approach is implemented, experimentally studied, and further developed in the work. Development and study concentrates on the multi-objective optimization aspect. The main outcomes of the work are versions of a method called Generalized Differential Evolution. The versions aim to improve the performance of the method in multi-objective optimization. A diversity preservation technique that is effective and efficient compared to previous diversity preservation techniques is developed. The thesis also studies the influence of control parameters of Differential Evolution in multi-objective optimization. Proposals for initial control parameter value selection are given. Overall, the work contributes to the diversity preservation of solutions in multi-objective optimization.

Corrosion behaviour of boiler tube materials during combustion of fuels containing Zn and Pb

Många förbränningsanläggningar som bränner utmanande bränslen såsom restfraktioner och avfall råkar ut för problem med ökad korrosion på överhettare och/eller vattenväggar pga. komponenter i bränslena som är korrosiva. För att minimera problemen i avfallseldade pannor hålls ångparametrarna på en relativt låg nivå, vilket drastiskt minskar energiproduktionen. Beläggningarna i avfallseldade pannor består till största delen av element som är förknippade med högtemperaturkorrosion: Cl, S, alkalimetaller, främst K och Na, och tungmetaller som Pb och Zn, och det finns också indikationer av Br-förekomst. Det låga ångtrycket i avfallseldade pannor påverkar också stålrörens temperatur i pannväggarna i eldstaden. I dagens läge hålls temperaturen normalt vid 300-400 °C. Alkalikloridorsakad (KCl, NaCl) högtemperaturkorrosion har inte rapporterats vara relevant vid såpass låga temperaturer, men närvaro av Zn- och Pb-komponenter i beläggningarna har påvisats förorsaka ökad korrosion redan vid 300-400 °C. Vid förbränning kan Zn och Pb reagera med S och Cl och bilda klorider och sulfater i rökgaserna. Dessa tungmetallföreningar är speciellt problematiska pga. de bildar lågsmältande saltblandningar. Dessa lågsmältande gasformiga eller fasta föreningar följer rökgasen och kan sedan fastna eller kondensera på kallare ytor på pannväggar eller överhettare för att sedan bilda aggressiva beläggningar. Tungmetallrika (Pb, Zn) klorider och sulfater ökar risken för korrosion, och effekten förstärks ytterligare vid närvaro av smälta. Motivet med den här studien var att få en bättre insikt i högtemperaturkorrosion förorsakad av Zn och Pb, samt att undersöka och prediktera beteendet och motståndskraften hos några stålkvaliteter som används i överhettare och pannväggar i tungmetallrika förhållanden och höga materialtemperaturer. Omfattande laboratorie-, småskale- och fullskaletest utfördes. Resultaten kan direkt utnyttjas i praktiska applikationer, t.ex. vid materialval, eller vid utveckling av korrosionsmotverkande verktyg för att hitta initierande faktorer och förstå deras effekt på högtemperaturkorrosion.

Element speciation and behaviour in metal-rich Boreal river and estuarine systems using ultrafiltration and chemical modelling

The bioavailability of metals and their potential for environmental pollution depends not simply on total concentrations, but is to a great extent determined by their chemical form. Consequently, knowledge of aqueous metal species is essential in investigating potential metal toxicity and mobility. The overall aim of this thesis is, thus, to determine the species of major and trace elements and the size distribution among the different forms (e.g. ions, molecules and mineral particles) in selected metal-enriched Boreal river and estuarine systems by utilising filtration techniques and geochemical modelling. On the basis of the spatial physicochemical patterns found, the fractionation and complexation processes of elements (mainly related to input of humic matter and pH-change) were examined. Dissolved (<1 kDa), colloidal (1 kDa-0.45 μm) and particulate (>0.45 μm) size fractions of sulfate, organic carbon (OC) and 44 metals/metalloids were investigated in the extremely acidic Vörå River system and its estuary in W Finland, and in four river systems in SW Finland (Sirppujoki, Laajoki, Mynäjoki and Paimionjoki), largely affected by soil erosion and acid sulfate (AS) soils. In addition, geochemical modelling was used to predict the formation of free ions and complexes in these investigated waters. One of the most important findings of this study is that the very large amounts of metals known to be released from AS soils (including Al, Ca, Cd, Co, Cu, Mg, Mn, Na, Ni, Si, U and the lanthanoids) occur and can prevail mainly in toxic forms throughout acidic river systems; as free ions and/or sulfate-complexes. This has serious effects on the biota and especially dissolved Al is expected to have acute effects on fish and other organisms, but also other potentially toxic dissolved elements (e.g. Cd, Cu, Mn and Ni) can have fatal effects on the biota in these environments. In upstream areas that are generally relatively forested (higher pH and contents of OC) fewer bioavailable elements (including Al, Cu, Ni and U) may be found due to complexation with the more abundantly occurring colloidal OC. In the rivers in SW Finland total metal concentrations were relatively high, but most of the elements occurred largely in a colloidal or particulate form and even elements expected to be very soluble (Ca, K, Mg, Na and Sr) occurred to a large extent in colloidal form. According to geochemical modelling, these patterns may only to a limited extent be explained by in-stream metal complexation/adsorption. Instead there were strong indications that the high metal concentrations and dominant solid fractions were largely caused by erosion of metal bearing phyllosilicates. A strong influence of AS soils, known to exist in the catchment, could be clearly distinguished in the Sirppujoki River as it had very high concentrations of a metal sequence typical of AS soils in a dissolved form (Ba, Br, Ca, Cd, Co, K, Mg, Mn, Na, Ni, Rb and Sr). In the Paimionjoki River, metal concentrations (including Ba, Cs, Fe, Hf, Pb, Rb, Si, Th, Ti, Tl and V; not typical of AS soils in the area) were high, but it was found that the main cause of this was erosion of metal bearing phyllosilicates and thus these metals occurred dominantly in less toxic colloidal and particulate fractions. In the two nearby rivers (Laajoki and Mynäjoki) there was influence of AS soils, but it was largely masked by eroded phyllosilicates. Consequently, rivers draining clay plains sensitive to erosion, like those in SW Finland, have generally high background metal concentrations due to erosion. Thus, relying on only semi-dissolved (<0.45 μm) concentrations obtained in routine monitoring, or geochemical modelling based on such data, can lead to a great overestimation of the water toxicity in this environment. The potentially toxic elements that are of concern in AS soil areas will ultimately be precipitated in the recipient estuary or sea, where the acidic metalrich river water will gradually be diluted/neutralised with brackish seawater. Along such a rising pH gradient Al, Cu and U will precipitate first together with organic matter closest to the river mouth. Manganese is relatively persistent in solution and, thus, precipitates further down the estuary as Mn oxides together with elements such as Ba, Cd, Co, Cu and Ni. Iron oxides, on the contrary, are not important scavengers of metals in the estuary, they are predicted to be associated only with As and PO4.

Flexible multibody approach in bone strain estimation during physical activity:

Bone strain plays a major role as the activation signal for the bone (re)modeling process, which is vital for keeping bones healthy. Maintaining high bone mineral density reduces the chances of fracture in the event of an accident. Numerous studies have shown that bones can be strengthened with physical exercise. Several hypotheses have asserted that a stronger osteogenic (bone producing) effect results from dynamic exercise than from static exercise. These previous studies are based on short-term empirical research, which provide the motivation for justifying the experimental results with a solid mathematical background. The computer simulation techniques utilized in this work allow for non-invasive bone strain estimation during physical activity at any bone site within the human skeleton. All models presented in the study are threedimensional and actuated by muscle models to replicate the real conditions accurately. The objective of this work is to determine and present loading-induced bone strain values resulting from physical activity. It includes a comparison of strain resulting from four different gym exercises (knee flexion, knee extension, leg press, and squat) and walking, with the results reported for walking and jogging obtained from in-vivo measurements described in the literature. The objective is realized primarily by carrying out flexible multibody dynamics computer simulations. The dissertation combines the knowledge of finite element analysis and multibody simulations with experimental data and information available from medical field literature. Measured subject-specific motion data was coupled with forward dynamics simulation to provide natural skeletal movement. Bone geometries were defined using a reverse engineering approach based on medical imaging techniques. Both computed tomography and magnetic resonance imaging were utilized to explore modeling differences. The predicted tibia bone strains during walking show good agreement with invivo studies found in the literature. Strain measurements were not available for gym exercises; therefore, the strain results could not be validated. However, the values seem reasonable when compared to available walking and running invivo strain measurements. The results can be used for exercise equipment design aimed at strengthening the bones as well as the muscles during workout. Clinical applications in post fracture recovery exercising programs could also be the target. In addition, the methodology introduced in this study, can be applied to investigate the effect of weightlessness on astronauts, who often suffer bone loss after long time spent in the outer space.

Experimental and discrete element simulation studies of bell-less charging of blast furnace

This thesis presents an experimental study and numerical study, based on the discrete element method (DEM), of bell-less charging in the blast furnace. The numerical models are based on the microscopic interaction between the particles in the blast furnace charging process. The emphasis is put on model validation, investigating several phenomena in the charging process, and on finding factors that influence the results. The study considers and simulates size segregation in the hopper discharging process, particle flow and behavior on the chute, which is the key equipment in the charging system, using mono-size spherical particles, multi-size spheres and nonspherical particles. The behavior of the particles at the burden surface and pellet percolation into a coke layer is also studied. Small-scale experiments are used to validate the DEM models.

Technology park as an element of innovative infrastructure- its role in internationalization support.

The Thesis concentrates on two central terms – Technology park and the resource-based view of the organization. General attention is devoted to competencies and capabilities of organizations that operate in foreign environment. It is difficult to go abroad without any experience and support from local government, especially for small or medium company. Technology and Science parks are the main sources of competitive advantage for this kind of organizations. They provide a huge range of services as well as business consultations and financial support on different stages of companies’ development. The Thesis was made with the assistance of Technopolis Oy in Lappeenranta. During the research companies in Finland and Russia were interviewed. Based on empirical findings important capabilities for entering foreign market were identified and some recommendations for the Technology park were given.

Tunable lumped-element bandpass filters for Cognitive Radio application

In this thesis the design of bandpass filters tunable at 400 MHz – 800 MHz was under research. Microwave filters are vital components which provide frequency selectivity in wide variety of electronic systems operating at high frequencies. Due to the occurrence of multi-frequency bands communication and diverse applications of wireless devices, requirement of tunable filters exists. The one of potential implementation of frequency-agile filters is frontends and spectrum sensors in Cognitive Radio (CR). The principle of CR is to detect and operate at a particular available spectrum without interfering with the primary user’s signals. This new method allows improving the efficiency of utilizing allocated spectrum such as TV band (400 MHz – 800 MHz). The focus of this work is development of sufficiently compact, low cost tunable filters with quite narrow bandwidth using currently available lumped-element components and PCB board technology. Filter design, different topologies and methods of tuning of bandpass filters are considered in this work. As a result, three types of topologies of bandpass filter were simulated and realised. They use digitally tunable capacitors (DTCs) for adjusting central frequency at TV "white space" spectrum. Measurements revealed that schematics presented in this work have proper output response and filters are successfully tuned by DTCs.

Application of the finite element method in cold forging processes

The demand for more efficient manufacturing processes has been increasing in the last few years. The cold forging process is presented as a possible solution, because it allows the production of parts with a good surface finish and with good mechanical properties. Nevertheless, the cold forming sequence design is very empirical and it is based on the designer experience. The computational modeling of each forming process stage by the finite element method can make the sequence design faster and more efficient, decreasing the use of conventional "trial and error" methods. In this study, the application of a commercial general finite element software - ANSYS - has been applied to model a forming operation. Models have been developed to simulate the ring compression test and to simulate a basic forming operation (upsetting) that is applied in most of the cold forging parts sequences. The simulated upsetting operation is one stage of the automotive starter parts manufacturing process. Experiments have been done to obtain the stress-strain material curve, the material flow during the simulated stage, and the required forming force. These experiments provided results used as numerical model input data and as validation of model results. The comparison between experiments and numerical results confirms the developed methodology potential on die filling prediction.

An alternative finite element formulation for determination of streamlines in two-dimensional problems

It is well known that the numerical solutions of incompressible viscous flows are of great importance in Fluid Dynamics. The graphics output capabilities of their computational codes have revolutionized the communication of ideas to the non-specialist public. In general those codes include, in their hydrodynamic features, the visualization of flow streamlines - essentially a form of contour plot showing the line patterns of the flow - and the magnitudes and orientations of their velocity vectors. However, the standard finite element formulation to compute streamlines suffers from the disadvantage of requiring the determination of boundary integrals, leading to cumbersome implementations at the construction of the finite element code. In this article, we introduce an efficient way - via an alternative variational formulation - to determine the streamlines for fluid flows, which does not need the computation of contour integrals. In order to illustrate the good performance of the alternative formulation proposed, we capture the streamlines of three viscous models: Stokes, Navier-Stokes and Viscoelastic flows.