Vendor Managed Inventory: the Critical Success Factors from the Manufacturer Point of View

Yritykset ovat pakotettuja erilaisiin yhteistyömuotoihin pärjätäkseen kiristyvässä kilpailussa. Yhteistyösuhteet kulkevat eri nimillä riippuen teollisuuden alasta ja siitä, missä kohtaa toimitusketjua ne toteutuvat, mutta periaatteessa kaikki pohjautuvat samaan ideaan kuin Vendor Managed Inventory (VMI); varastoon jakysyntään liittyvä tieto jaetaan toimitusketjun eri osapuolien kesken, jotta tuotanto, jakelu ja varastonhallinta olisi mahdollista optimoida. Vendor Managed Inventory on ideana yksinkertainen, mutta vaatii onnistuakseen paljon. Perusolettamus on, että toimittajan on kyettävä hallinnoimaan asiakkaan varastoa paremmin kuin asiakas itse. Tämä ei kuitenkaan ole mahdollista ilman riittävää yhteistyötä, oikeanlaista informaatiota tai sopivia tuoteominaisuuksia. Tämän työn tarkoitus on esitellä kriittiset menestystekijät valmistajan kannalta, kun näkyvyys todelliseen kysyntään on heikko ja kyseessäolevat tuotteet ovat ominaisuuksiltaan toimintamalliin huonosti soveltuvia. VMItoimintamallin soveltuvuus matkapuhelimia valmistavan yrityksen liiketoimintaan, sekä sen vaikutus asiakasyhteistyöhön, kannattavuuteen ja toiminnan tehostamiseen on myös tutkittu.

Product Standardization of Shell and Tube Heat Exchangers

Diplomityön tavoitteena oli selvittää, kuinka kohdeyrityksessä nykyhetkellä pitkältiräätälöitynä tuotetut putkilämmönvaihtimet voitaisiin standardisoida, jotta pystyttäisiin kohdistamaan resursseja oikein ja parantamaan siten yrityksen taloudellista suorituskykyä. Tutkimuksen edetessä määräävimmäksi tekijäksi työn tuloksia ajatellen nousi taloudellinen standardisointiaste, jonka perusteeksi kohdeyrityksen putkilämmönvaihtimissa valittiin standardisoitu suunnitteluohjeisto. Suunnitteluohjeiston lisäksi tuotestandardiin liitettiin ehdotus toimintapojen automatisoimisesta parametrisen valintataulukon sekä sähköisen manuaalin avulla. Työssä tuotestandardisointia tarkastellaan rationalisointi-investointina ja sen kannattavuutta on tarkasteltu investointilaskelmien sekä herkkyys analyysin avulla. Alkuarvot investointilaskelmissa perustuvat työssä yhdelle putkilämmönvaihtimelletoteutettuun tuotestandardisointitapaan, jos tätä tapaa käytettäisiin jatkossa kaikkiin kyseisen yksikön putkilämmönvaihtimiin.

Konsernin yksiköiden välinen yhteistyö: erikoistumisen vaikutukset materiaalinkäyttöön

Diplomityö tehtiin Suomessa toimivaan metalliteollisuusalan konserniin. Tutkimuksen päämääränä oli selvittää yksiköiden tuotannollisen erikoistumisen avulla saavutettavia materiaali- ja kustannussäästöjä. Samalla haluttiin kartoittaa yksiköiden välisen yhteistyön nykytilaa, sen ongelmia ja mahdollisuuksia. Teoreettisena lähestymistapana yhteistyön osalta käytettiin yritysten välistä verkostoitumista. Erikoistumista käsittelevässä teoriaosuudessa asiaa tutkittiindifferoinnin näkökulmasta. Tietoja hankittiin haastattelemalla, tutkimalla toimintaprosesseja ja nykyistä materiaalinkäyttöä. Tutkimus näytti toteen johdon oletuksen siitä, että yksiköiden erikoistuessa saavutettaisiin mittavia kustannussäästöjä. Yksiköt eivät ole tällä hetkellä erikoistuneita, ja niiden välisen yhteistyön kehittäminen on vasta aluillaan. Yhteistyön suurimpana ongelmana on yksiköiden keskinäinen kilpailutilanne. Huomionarvoista on se, että tutkimuksen kohteena olleet yhteistyö ja erikoistuminen tukevat toisiaan.

Sähkömittareiden kaukoluennan kannattavuus ja käyttöönotto sähköverkkoyhtiössä

Sähkömittareiden kaukoluenta (AMR) on tällä hetkellä ajankohtainen aihe, koska useat verkkoyhtiöt ovat tehneet jo päätöksen mittaustoiminnan automatisoinnista ja monissa yhtiöissä ovat selvitykset parhaillaan menossa tai suunnitteilla. Erilaisten ennusteiden mukaan kaikki Suomen sähkömittarit tulevat ajan myötä kaukoluettaviksi, mutta aikataulun arviot vaihtelevat viidestä viiteentoista vuoteen. Diplomityössä on tutkittu Lahti Energia Oy:lle soveltuvaa sähkömittareiden kaukoluentajärjestelmää ja siihen investoimisen kannattavuutta. Tarkastelun kohteena on ollut yhtiölle kaukoluennasta kertyvät kustannukset ja sen avulla saavutettavat säästöt. Koska mittareiden kaukoluennasta on yhtiössä vain vähän kokemusta, lasketut säästöt perustuvat olettamukseen ja arvioituihin lukemiin. Lisäksi työssä on käsitelty yhtiön jakelualueen alueittaista jaottelua kaukoluennan kannattavuuden suhteen ja tutkittu kaukoluennan vaikutuksia yhtiön toimintoihin sekä sen tuomia mahdollisuuksia. Kaukoluennan myötä saadaan täsmällistä tietoa energiankulutuksesta ja asiakkaita voidaan laskuttaa todelliseen mittarinlukemaan perustuen. Sen avulla tulevat mahdollisiksi myös useat lisäpalvelut tai toiminnot, kuten tuntimittaus, sähkön laadun seuranta, sähkökatkojen rekisteröinti ja sähköjen etäkatkaisu. Kaikkia kyseisiä palveluita ei tarvitsevälttämättä hankkia kerralla vaan ne voidaan ottaa myös optiona.

Torque vibration model of axial-flux surface-mounted permanent magnet synchronous machine

In order that the radius and thus ununiform structure of the teeth and otherelectrical and magnetic parts of the machine may be taken into consideration the calculation of an axial flux permanent magnet machine is, conventionally, doneby means of 3D FEM-methods. This calculation procedure, however, requires a lotof time and computer recourses. This study proves that also analytical methods can be applied to perform the calculation successfully. The procedure of the analytical calculation can be summarized into following steps: first the magnet is divided into slices, which makes the calculation for each section individually, and then the parts are submitted to calculation of the final results. It is obvious that using this method can save a lot of designing and calculating time. Thecalculation program is designed to model the magnetic and electrical circuits of surface mounted axial flux permanent magnet synchronous machines in such a way, that it takes into account possible magnetic saturation of the iron parts. Theresult of the calculation is the torque of the motor including the vibrations. The motor geometry and the materials and either the torque or pole angle are defined and the motor can be fed with an arbitrary shape and amplitude of three-phase currents. There are no limits for the size and number of the pole pairs nor for many other factors. The calculation steps and the number of different sections of the magnet are selectable, but the calculation time is strongly depending on this. The results are compared to the measurements of real prototypes. The permanent magnet creates part of the flux in the magnetic circuit. The form and amplitude of the flux density in the air-gap depends on the geometry and material of the magnetic circuit, on the length of the air-gap and remanence flux density of the magnet. Slotting is taken into account by using the Carter factor in the slot opening area. The calculation is simple and fast if the shape of the magnetis a square and has no skew in relation to the stator slots. With a more complicated magnet shape the calculation has to be done in several sections. It is clear that according to the increasing number of sections also the result will become more accurate. In a radial flux motor all sections of the magnets create force with a same radius. In the case of an axial flux motor, each radial section creates force with a different radius and the torque is the sum of these. The magnetic circuit of the motor, consisting of the stator iron, rotor iron, air-gap, magnet and the slot, is modelled with a reluctance net, which considers the saturation of the iron. This means, that several iterations, in which the permeability is updated, has to be done in order to get final results. The motor torque is calculated using the instantaneous linkage flux and stator currents. Flux linkage is called the part of the flux that is created by the permanent magnets and the stator currents passing through the coils in stator teeth. The angle between this flux and the phase currents define the torque created by the magnetic circuit. Due to the winding structure of the stator and in order to limit the leakage flux the slot openings of the stator are normally not made of ferromagnetic material even though, in some cases, semimagnetic slot wedges are used. In the slot opening faces the flux enters the iron almost normally (tangentially with respect to the rotor flux) creating tangential forces in the rotor. This phenomenon iscalled cogging. The flux in the slot opening area on the different sides of theopening and in the different slot openings is not equal and so these forces do not compensate each other. In the calculation it is assumed that the flux entering the left side of the opening is the component left from the geometrical centre of the slot. This torque component together with the torque component calculated using the Lorenz force make the total torque of the motor. It is easy to assume that when all the magnet edges, where the derivative component of the magnet flux density is at its highest, enter the slot openings at the same time, this will have as a result a considerable cogging torque. To reduce the cogging torquethe magnet edges can be shaped so that they are not parallel to the stator slots, which is the common way to solve the problem. In doing so, the edge may be spread along the whole slot pitch and thus also the high derivative component willbe spread to occur equally along the rotation. Besides forming the magnets theymay also be placed somewhat asymmetric on the rotor surface. The asymmetric distribution can be made in many different ways. All the magnets may have a different deflection of the symmetrical centre point or they can be for example shiftedin pairs. There are some factors that limit the deflection. The first is that the magnets cannot overlap. The magnet shape and the relative width compared to the pole define the deflection in this case. The other factor is that a shifting of the poles limits the maximum torque of the motor. If the edges of adjacent magnets are very close to each other the leakage flux from one pole to the other increases reducing thus the air-gap magnetization. The asymmetric model needs some assumptions and simplifications in order to limit the size of the model and calculation time. The reluctance net is made for symmetric distribution. If the magnets are distributed asymmetrically the flux in the different pole pairs will not be exactly the same. Therefore, the assumption that the flux flows from the edges of the model to the next pole pairs, in the calculation model from one edgeto the other, is not correct. If it were wished for that this fact should be considered in multi-pole pair machines, this would mean that all the poles, in other words the whole machine, should be modelled in reluctance net. The error resulting from this wrong assumption is, nevertheless, irrelevant.

Selective catalytic reduction of nitrogen oxides with ammonia in forced unsteady state reactors - Case based reasoning and mathematical model simulation reasoning

The application of forced unsteady-state reactors in case of selective catalytic reduction of nitrogen oxides (NOx) with ammonia (NH3) is sustained by the fact that favorable temperature and composition distributions which cannot be achieved in any steady-state regime can be obtained by means of unsteady-state operations. In a normal way of operation the low exothermicity of the selective catalytic reduction (SCR) reaction (usually carried out in the range of 280-350°C) is not enough to maintain by itself the chemical reaction. A normal mode of operation usually requires supply of supplementary heat increasing in this way the overall process operation cost. Through forced unsteady-state operation, the main advantage that can be obtained when exothermic reactions take place is the possibility of trapping, beside the ammonia, the moving heat wave inside the catalytic bed. The unsteady state-operation enables the exploitation of the thermal storage capacity of the catalyticbed. The catalytic bed acts as a regenerative heat exchanger allowing auto-thermal behaviour when the adiabatic temperature rise is low. Finding the optimum reactor configuration, employing the most suitable operation model and identifying the reactor behavior are highly important steps in order to configure a proper device for industrial applications. The Reverse Flow Reactor (RFR) - a forced unsteady state reactor - corresponds to the above mentioned characteristics and may be employed as an efficient device for the treatment of dilute pollutant mixtures. As a main disadvantage, beside its advantages, the RFR presents the 'wash out' phenomena. This phenomenon represents emissions of unconverted reactants at every switch of the flow direction. As a consequence our attention was focused on finding an alternative reactor configuration for RFR which is not affected by the incontrollable emissions of unconverted reactants. In this respect the Reactor Network (RN) was investigated. Its configuration consists of several reactors connected in a closed sequence, simulating a moving bed by changing the reactants feeding position. In the RN the flow direction is maintained in the same way ensuring uniformcatalyst exploitation and in the same time the 'wash out' phenomena is annulated. The simulated moving bed (SMB) can operate in transient mode giving practically constant exit concentration and high conversion levels. The main advantage of the reactor network operation is emphasizedby the possibility to obtain auto-thermal behavior with nearly uniformcatalyst utilization. However, the reactor network presents only a small range of switching times which allow to reach and to maintain an ignited state. Even so a proper study of the complex behavior of the RN may give the necessary information to overcome all the difficulties that can appear in the RN operation. The unsteady-state reactors complexity arises from the fact that these reactor types are characterized by short contact times and complex interaction between heat and mass transportphenomena. Such complex interactions can give rise to a remarkable complex dynamic behavior characterized by a set of spatial-temporal patterns, chaotic changes in concentration and traveling waves of heat or chemical reactivity. The main efforts of the current research studies concern the improvement of contact modalities between reactants, the possibility of thermal wave storage inside the reactor and the improvement of the kinetic activity of the catalyst used. Paying attention to the above mentioned aspects is important when higher activity even at low feeding temperatures and low emissions of unconverted reactants are the main operation concerns. Also, the prediction of the reactor pseudo or steady-state performance (regarding the conversion, selectivity and thermal behavior) and the dynamicreactor response during exploitation are important aspects in finding the optimal control strategy for the forced unsteady state catalytic tubular reactors. The design of an adapted reactor requires knowledge about the influence of its operating conditions on the overall process performance and a precise evaluation of the operating parameters rage for which a sustained dynamic behavior is obtained. An apriori estimation of the system parameters result in diminution of the computational efforts. Usually the convergence of unsteady state reactor systems requires integration over hundreds of cycles depending on the initial guess of the parameter values. The investigation of various operation models and thermal transfer strategies give reliable means to obtain recuperative and regenerative devices which are capable to maintain an auto-thermal behavior in case of low exothermic reactions. In the present research work a gradual analysis of the SCR of NOx with ammonia process in forced unsteady-state reactors was realized. The investigation covers the presentationof the general problematic related to the effect of noxious emissions in the environment, the analysis of the suitable catalysts types for the process, the mathematical analysis approach for modeling and finding the system solutions and the experimental investigation of the device found to be more suitable for the present process. In order to gain information about the forced unsteady state reactor design, operation, important system parameters and their values, mathematical description, mathematicalmethod for solving systems of partial differential equations and other specific aspects, in a fast and easy way, and a case based reasoning (CBR) approach has been used. This approach, using the experience of past similarproblems and their adapted solutions, may provide a method for gaining informations and solutions for new problems related to the forced unsteady state reactors technology. As a consequence a CBR system was implemented and a corresponding tool was developed. Further on, grooving up the hypothesis of isothermal operation, the investigation by means of numerical simulation of the feasibility of the SCR of NOx with ammonia in the RFRand in the RN with variable feeding position was realized. The hypothesis of non-isothermal operation was taken into account because in our opinion ifa commercial catalyst is considered, is not possible to modify the chemical activity and its adsorptive capacity to improve the operation butis possible to change the operation regime. In order to identify the most suitable device for the unsteady state reduction of NOx with ammonia, considering the perspective of recuperative and regenerative devices, a comparative analysis of the above mentioned two devices performance was realized. The assumption of isothermal conditions in the beginningof the forced unsteadystate investigation allowed the simplification of the analysis enabling to focus on the impact of the conditions and mode of operation on the dynamic features caused by the trapping of one reactant in the reactor, without considering the impact of thermal effect on overall reactor performance. The non-isothermal system approach has been investigated in order to point out the important influence of the thermal effect on overall reactor performance, studying the possibility of RFR and RN utilization as recuperative and regenerative devices and the possibility of achieving a sustained auto-thermal behavior in case of lowexothermic reaction of SCR of NOx with ammonia and low temperature gasfeeding. Beside the influence of the thermal effect, the influence of the principal operating parameters, as switching time, inlet flow rate and initial catalyst temperature have been stressed. This analysis is important not only because it allows a comparison between the two devices and optimisation of the operation, but also the switching time is the main operating parameter. An appropriate choice of this parameter enables the fulfilment of the process constraints. The level of the conversions achieved, the more uniform temperature profiles, the uniformity ofcatalyst exploitation and the much simpler mode of operation imposed the RN as a much more suitable device for SCR of NOx with ammonia, in usual operation and also in the perspective of control strategy implementation. Theoretical simplified models have also been proposed in order to describe the forced unsteady state reactors performance and to estimate their internal temperature and concentration profiles. The general idea was to extend the study of catalytic reactor dynamics taking into account the perspectives that haven't been analyzed yet. The experimental investigation ofRN revealed a good agreement between the data obtained by model simulation and the ones obtained experimentally.

Mass transfer and particleinteractions in granular systems and suspension flows

The purpose of this study was to investigate some important features of granular flows and suspension flows by computational simulation methods. Granular materials have been considered as an independent state ofmatter because of their complex behaviors. They sometimes behave like a solid, sometimes like a fluid, and sometimes can contain both phases in equilibrium. The computer simulation of dense shear granular flows of monodisperse, spherical particles shows that the collisional model of contacts yields the coexistence of solid and fluid phases while the frictional model represents a uniform flow of fluid phase. However, a comparison between the stress signals from the simulations and experiments revealed that the collisional model would result a proper match with the experimental evidences. Although the effect of gravity is found to beimportant in sedimentation of solid part, the stick-slip behavior associated with the collisional model looks more similar to that of experiments. The mathematical formulations based on the kinetic theory have been derived for the moderatesolid volume fractions with the assumption of the homogeneity of flow. In orderto make some simulations which can provide such an ideal flow, the simulation of unbounded granular shear flows was performed. Therefore, the homogeneous flow properties could be achieved in the moderate solid volume fractions. A new algorithm, namely the nonequilibrium approach was introduced to show the features of self-diffusion in the granular flows. Using this algorithm a one way flow can beextracted from the entire flow, which not only provides a straightforward calculation of self-diffusion coefficient but also can qualitatively determine the deviation of self-diffusion from the linear law at some regions nearby the wall inbounded flows. Anyhow, the average lateral self-diffusion coefficient, which was calculated by the aforementioned method, showed a desirable agreement with thepredictions of kinetic theory formulation. In the continuation of computer simulation of shear granular flows, some numerical and theoretical investigations were carried out on mass transfer and particle interactions in particulate flows. In this context, the boundary element method and its combination with the spectral method using the special capabilities of wavelets have been introduced as theefficient numerical methods to solve the governing equations of mass transfer in particulate flows. A theoretical formulation of fluid dispersivity in suspension flows revealed that the fluid dispersivity depends upon the fluid properties and particle parameters as well as the fluid-particle and particle-particle interactions.

Sahalaitosten häiriömittauskäytännön yhtenäistäminen

Työn tavoitteena oli selvittää kahdeksan sahalaitoksen häiriöseurannan nykytila sekä selvittämisen jälkeen ehdottaa sahalaitoksille otettavaksi käyttöön yhtenäinen samoihin häiriön luokitus- ja kirjaamisperiaatteisiin perustuva mittauskäytäntö. Yhtenäisen käytännön myötä sahalaitoksilta saatavat häiriötiedot ovat sahalaitosten kesken vertailukelpoisia. Mittauskäytännön yhtenäistämisellä pyritään nostamaan tuotantolinjojen käytettävyyttä. Sahalaitosten häiriömittauskäytännöissä oletettiin olevan merkittäviä eroja. Työ suoritettiin lähettämällä kysymykset sähköpostilla etukäteen sahalaitoksille, jonka jälkeen käytiin sahalaitoksissa haastattelemassa häiriöasioiden kanssa tekemisissä olevia henkilöitä. Haastattelujen jälkeen sahalaitoksilta saatuja tietoja täydennettiin sähköpostin välityksellä. Näiden toimintatapojen lisäksi tutkittiin sahalaitoksilta saatuja häiriöraportteja ja syykoodilistoja sekä verrattiin tutkimuksessa satuja tuloksia aihetta käsittelevään kirjallisuuteen. Tutkimustulokset vahvistavat työn aloitusvaiheessa tehdyn oletuksen, jonka mukaan sahalaitosten häiriömittauskäytännöissä on merkittäviä eroja. Tutkimusta hyödyntäen asiantuntijatyöryhmä yhtenäisti sahalinjojen ja tasaamoiden pien-häiriöiden ja varsinaisten häiriöiden laukaisurajat sekä häiriöiden mittauspaikat. Myös syykoodilistat yhtenäistettiin. Tämän lisäksi muodostettiin yhtenäinen vertailuraportti, jotta sahalaitosten häiriötietojen vertaileminen on mahdollista.

Influence of software development process quality on product quality

Ohjelmistojen tärkeys nykypäivän yhteiskunnalle kasvaa jatkuvasti. Monia ohjelmistoprojekteja vaivaavat ongelmat aikataulussa pysymisestä, korkean tuottavuuden ylläpitämisestä ja riittävän korkeasta laadusta. Ohjelmistokehitysprosessien parantamisessa on naiden ongelmien minimoimiseksi tehty suuria investointeja. Investointien syynä on ollut olettamus ohjelmistokehityksen kapasiteetin suora riippuvuus tuotteen laadusta. Tämän tutkimuksen tarkoituksena oli tutkia Ohjelmistokehitysprosessien parantamisen mahdollisuuksia. Olemassaolevat ohjelmistokehityksen ja Ohjelmistokehitysprosessin parantamisen mallit, tekniikat ja metodologiat esiteltiin. Esiteltyjen mallien, tekniikoiden ja metodologioiden soveltuvuus analysoitiin ja suositus mallien käytöstä annettiin.

Strategia ja tietojohtaminen asiantuntijaorganisaatiossa. Case: Laurea-ammattikorkeakoulun Espoo-Vantaan alueyksikkö

Tutkielma rakentui organisaation strategisen johtamisen ja tietojohtamisen teorialle. Tutkielmassa etsittiin niitä malleja, menetelmiä ja toimintatapoja, jotka tukevat tietojohtamisen juurruttamista organisaation toimintaan tavalla, mikä tukee asiantuntijaorganisaation strategisten tavoitteiden toteuttamista, organisaation uudistumista ja asiantuntijaorganisaation kyvykkyyden kehittämistä. Tutkielman empiirisessä osassa kohdeorganisaationa oli Laurea-ammattikorkeakoulu. Organisaation kyvykkyyttä toteuttaa valittua strategiaa selvitettiin suorittamalla mittaus KM-factor™ mittarilla. Mittauksessa otoksena oli ammattikorkeakoulun Porvoo-Vantaa -alueyksikön koko henkilöstö. Mittausta täydennettiin organisaatiossa tehdyillä haastatteluilla. Organisaatiossa tehty empiirinen tutkimus ja suoritettu mittaus selvittivät organisaation kyvykkyyttä suoriutua strategian toteuttamisessa suhteessa muissa asiantuntijaorganisaatioissa saatuihin mittaustuloksiin. Tutkielman tietojohtamisen ja strategisen johtamisen teoria ja saatu mittaustulos tukivat käsitystä siitä, että asiantuntijaorganisaatioiden kyvykkyydessä uusiutumiseen löytyy yhteisiä piirteitä. Organisaatiolle valitut toimintatavat, mallit ja menetelmät voivat merkittävästi tukea organisaation innovaatiopotentiaalia. Asiantuntijaorganisaatioissa korostuu tutkielman mukaan kyvykkyys yhteisen näkemyksen ja tavoitetilan juurruttamisessa ja sitä tukevien käytäntöjen omaksumisessa yli organisaatiorajojen.

Opettajan monikulttuurinen työ

Teacher's multicultural work The purpose of the present study is to explore teachers’ conceptions of their work as teachers of multicultural students. Teachers’ experiences of multicultural work and conceptions derived from them are part of the teacher’s multicultural competence which is seen as a key component of the teacher’s multicultural teachership. The teacher’s multicultural competence consists of the teacher’s cultural knowledge, pedagogical skills and experiences and attitudes related to multiculturalism. The teacher’s multicultural competence constitutes the basis on which the teacher implements multicultural education. The foundation for the teacher’s work is laid by laws and decrees, curricula, regulations issued by authorities in charge of the education of immigrant students, resources available and other demands and expectations set by the ambient society. The study was conducted in the city of Turku, Finland. The sample consisted of class teachers who taught both immigrant and majority students. Main objects of study in the theoretical part are the multicultural and pluralistic school and the multicultural teachership. The basic assumption is that the multicultural and pluralistic school forms the frame of activity in which the teacher implements multicultural teaching. The research strategy is based on methodological triangulation. The quantitative part of the study was carried out using a questionnaire typical of survey methods. The questionnaire was returned by 71 teachers. The qualitative part was conducted using theme-based interviews typical of phenomenological philosophical research. Of the total of teachers who returned the questionnaire, twelve (12) teachers were selected for interviews. According to the results, the participating teachers enjoyed their work regardless of the ample extra work caused by the students with immigrant backgrounds. The teachers experienced their work as teachers of multicultural student groups as strenuous, yet challenging. Students with immigrant backgrounds had caused many changes in the teacher’s work. The teachers regarded their multicultural skills as inadequate in relation to the demands of the work. They had not received education related to teaching students with immigrant backgrounds, but they were ready for in-service education. The teachers’ previous attitudes concerning immigrant students had been enforced. Teaching experiences strengthened the earlier, both positive and negative, attitudes. The central problems related to multiculturalism in the teacher’s work were caused by the deficient Finnish skills of the students with immigrant background. This was apparent in both teaching and learning as well as in contacts with parents. The teachers reported on relatively few inclusions of multicultural angles in their teaching. However, they believed that they could aid students with different cultural backgrounds in their integration process. At the same time they felt that their own chances to enhance the students’ cultural identities were slim. On the basis of the interviews conducted in connection with the teacher’s multicultural competence, the teachers were divided into three groups: assimilative, indeterminate and integrating multicultural teachers. The present study provides a strong indication that teachers tend to interpret multiculturalism in narrow terms. School activities, such as Finnish as a second language, first language and religious instruction, which were targeted exclusively at immigrant students were in most cases considered adequate. A holistic, cross-disciplinary, all-inclusive multicultural education that would permeate all school activities remains largely unimplemented.

On Option Price Information Content and Extraction of Implied Probability Distributions

In this study we used market settlement prices of European call options on stock index futures to extract implied probability distribution function (PDF). The method used produces a PDF of returns of an underlying asset at expiration date from implied volatility smile. With this method, the assumption of lognormal distribution (Black-Scholes model) is tested. The market view of the asset price dynamics can then be used for various purposes (hedging, speculation). We used the so called smoothing approach for implied PDF extraction presented by Shimko (1993). In our analysis we obtained implied volatility smiles from index futures markets (S&P 500 and DAX indices) and standardized them. The method introduced by Breeden and Litzenberger (1978) was then used on PDF extraction. The results show significant deviations from the assumption of lognormal returns for S&P500 options while DAX options mostly fit the lognormal distribution. A deviant subjective view of PDF can be used to form a strategy as discussed in the last section.

Partnering in the Dynamic Environment: The Role of Trust in Asymmetric Technology Partnership Formation

The purpose of this study was to increase the understanding of the role and nature of trust in asymmetric technology partnership formation. In the knowledge-based "learning race" knowledge is considered as a primary source for competitive advantage. In the emerging ICT sector the high pace of technological change, the convergence of technologies and industries as well as the increasing complexity and uncertainty have forced even the largest players to seek cooperation for complementary knowledge and capabilities. Small technology firms need the complementary resources and legitimacy of the large firms to grow and compete in the global market place. Most of the earlier research indicates, however, that partnerships with asymmetric size, managerial resources and cultures have failed. A basic assumption supported by earlier research was that trust is a critical factor in asymmetric technology partnership formation. Asymmetric technology partnership formation is a dynamic and multi-dimensional process, and consequently a holistic research approach was selected. Research issue was approached from different levels: the individual decision-maker, the firm and the relationship between the parties. Also the impact of the dynamic environment and technology content was analyzed. A multitheoretical approach and a qualitative research method with in-depth interviews in five large ICT companies and eight small ICT companies enabled a holistic and rich view of the research issue. Study contributes on the scarce understanding on the nature and evolution of trust in asymmetric technology partnership formation. It sheds also light on the specific nature of asymmetric technology partnerships. The partnerships were found to be tentative and the diverse strategic intent of small and large technology firms appeared as a major challenge. The role of the boundary spanner was highlighted as a possibility to match the incompatible organizational cultures. A shared vision was found to be a pre-condition for individual-based fast trust leading to intuitive decision-making and experimentation. The relationships were tentative and they were continuously re-evaluated through the key actors' sense making of the technology content, asymmetry and the dynamic environment. A multi-dimensional conceptualization for trust was created and propositions on the role and nature of trust for further research are given. The purpose of this study was to increase the understanding of the role and nature of trust in asymmetric technology partnership formation. In the knowledge-based "learning race" knowledge is considered as a primary source for competitive advantage. In the emerging ICT sector the high pace of technological change, the convergence of technologies and industries as well as the increasing complexity and uncertainty have forced even the largest players to seek cooperation for complementary knowledge and capabilities. Small technology firms need the complementary resources and legitimacy of the large firms to grow and compete in the global market place. Most of the earlier research indicates, however, that partnerships with asymmetric size, managerial resources and cultures have failed. A basic assumption supported by earlier research was that trust is a critical factor in asymmetric technology partnership formation. Asymmetric technology partnership formation is a dynamic and multi-dimensional process, and consequently a holistic research approach was selected. Research issue was approached from different levels: the individual decision-maker, the firm and the relationship between the parties. Also the impact of the dynamic environment and technology content was analyzed. A multitheoretical approach and a qualitative research method with in-depth interviews in five large ICT companies and eight small ICT companies enabled a holistic and rich view of the research issue. Study contributes on the scarce understanding on the nature and evolution of trust in asymmetric technology partnership formation. It sheds also light on the specific nature of asymmetric technology partnerships. The partnerships were found to be tentative and the diverse strategic intent of small and large technology firms appeared as a major challenge. The role of the boundary spanner was highlighted as a possibility to match the incompatible organizational cultures. A shared vision was found to be a pre-condition for individual-based fast trust leading to intuitive decision-making and experimentation. The relationships were tentative and they were continuously re-evaluated through the key actors' sense making of the technology content, asymmetry and the dynamic environment. A multi-dimensional conceptualization for trust was created and propositions on the role and nature of trust for further research are given.

Yritysten sosiaalisen vastuun tarkastelua vuosina 2000 ja 2006/Corporate Social Responsibility year 2000 and 2006

Tutkimuksen tarkoitus on selvittää, miten yritysten ajattelutapa sosiaalisesta vastuusta on muuttunut vuodesta 2000 vuoteen 2006. Lisäksi vastataan kysymyksiin, mistä osa-alueista sosiaalinen vastuu muodostuu, miten kirjoittelu sosiaalisesta vastuusta on muuttunut määrällisesti ja sisällöllisesti. Tutkimus on luonteeltaan laadullinen ja analyysimenetelmänä on käytetty diskurssianalyysiä. Tutkimusaineisto koostuu johtavien talousalan lehtien Talouselämä ja Kauppalehden artikkeleista vuosilta 2000 ja 2006. Artikkeleista saatua tietoa peilataan teoriatietoon ja näin pyritään hahmottamaan tutkimuksen tulokset. Tutkimuksen tulokset osoittavat, että vuonna 2000 lehdet ovat kirjoittaneet jonkin verran enemmän sosiaalisesta vastuusta kuin vuonna 2006. Molempina vuosina sijoittavat arvostavat vastuullista toimintaa. Yrityksen arvot ovat usein määritelty ”ylhäältä-alas”. Työntekijöiden pahoinvointi on lisääntynyt entisestään vuodesta 2000 vuoteen 2006. Syynä tähän kirjoitusten mukaan ovat esimerkiksi huono johtaminen ja työtehtävien organisointi. Sosiaalisen vastuun mittaaminen on hankalaa ja ikääntyviä työntekijöitä yritetään pitää yrityksissä mahdollisimman pitkään. Tulospalkkausjärjestelmät ovat käytössä muutamassa yrityksessä. Työn, perheen ja vapaa-ajan sovittaminen yhteen on vuodesta 2000 muuttunut entistäkin tärkeämmäksi vuonna 2006. Lopputulos on, että sosiaalisen vastuun kanto on huonontunut vuodesta 2000 vuoteen 2006.

Statistical Inversion Theory in X-ray Tomography

In this thesis the X-ray tomography is discussed from the Bayesian statistical viewpoint. The unknown parameters are assumed random variables and as opposite to traditional methods the solution is obtained as a large sample of the distribution of all possible solutions. As an introduction to tomography an inversion formula for Radon transform is presented on a plane. The vastly used filtered backprojection algorithm is derived. The traditional regularization methods are presented sufficiently to ground the Bayesian approach. The measurements are foton counts at the detector pixels. Thus the assumption of a Poisson distributed measurement error is justified. Often the error is assumed Gaussian, altough the electronic noise caused by the measurement device can change the error structure. The assumption of Gaussian measurement error is discussed. In the thesis the use of different prior distributions in X-ray tomography is discussed. Especially in severely ill-posed problems the use of a suitable prior is the main part of the whole solution process. In the empirical part the presented prior distributions are tested using simulated measurements. The effect of different prior distributions produce are shown in the empirical part of the thesis. The use of prior is shown obligatory in case of severely ill-posed problem.