[Auf dem Wasser zu singen]

Soitinnus: lauluääni (sopraano), piano.

[Mun kanteleeni kauniimmin]

Soitinnus: lauluääni (sopraano), kantele.

Varjo : Sibelius-Akatemian kopio

Esittäjätiedot ja vuosiluvut saatu Yleisradiolta sillä oletuksella että kyseessä on juuri tämä 1981 esitys (nauhakotelossa Ylen nauhanumero, jota ei kuitenkaan löydy Ylen tietokannasta).

[Die Verschweigung]

Soitinnus: lauluääni (sopraano), piano.

[Nimmersatte Liebe]

Soitinnus: lauluääni (sopraano), piano.

[Begegnung]

Soitinnus: lauluääni (sopraano), piano.

[Trio klarinetille, fagotille ja pianolle]

Soitinnus: klarinetti, fagotti, piano.

[Das verlassene Mägdlein]

Soitinnus: lauluääni (sopraano), piano.

[An eine Äolsharfe]

Soitinnus: lauluääni (sopraano), piano.

Filosofien ystävyydestä

Kirjallisuusarvostelu

Bonding of Composite Resin to Alumina and Zirconia Ceramics with Special Emphasis on Surface Conditioning and Use of Coupling Agents

Dental oxide ceramics have been inspired by their biocompability and mechanical properties which have made durable all-ceramic structures possible. Clinical longevity of the prosthetic structures is dependent on effective bonding with luting cements. As the initial shear bond strength values can be comparable with several materials and procedures, long-term durability is affected by ageing. Aims of the current study were: to measure the shear bond strength of resin composite-to-ceramics and to evaluate the longevity of the bond; to analyze factors affecting the bond, with special emphasis on: the form of silicatization of the ceramic surface; form of silanization; type of resin primer and the effect of the type of the resin composite luting cement; the effect of ageing in water was studied regarding its effect to the endurance of the bond. Ceramic substrates were alumina and yttrium stabilized zirconia. Ceramic conditioning methods included tribochemical silicatization and use of two silane couplings agents. A commercial silane primer was used as a control silane. Various combinations of conditioning methods, primers and resin cements were tested. Bond strengths were measured by shear bond strength method. The longevity of the bond was generally studied by thermocycling the materials in water. Additionally, in one of the studies thermal cycling was compared with long-term water storaging. Results were analysed statistically with ANOVA and Weibull analysis. Tribochemical treatment utilizing air pressure of 150 kPa resulted shear bond strengths of 11.2 MPa to 18.4 MPa and air pressure of 450 kPa 18.2 MPa to 30.5 MPa, respectively. Thermocycling of 8000 cycles or four years water storaging both decreased shear bond strength values to a range of 3.8 MPa to 7.2 MPa whereas initial situation varied from 16.8. Mpa to 23.0 MPa. The silane used in studies had no statistical significance. The use of primers without 10-MDP resulted spontaneous debonding during thermocycling or shear bond strengths below 5 MPa. As conclusion, the results showed superior long-term bonding with primers containing 10-MDP. Silicatization with silanizing showed improved initial shear bond strength values which considerably decreased with ageing in water. Thermal cycling and water storing for up to four years played the major role in reduction of bond strength, which could be due to thermal fatigue of the bonding interface and hydrolytic degradation of the silane coupled interface.

Monikansalliset yritykset Venäjällä

Tämä kandidaatintyö käsittelee monikansallisten yritysten mahdollisuuksia sekä vaikutuksia Venäjällä. Työ koostuu neljästä kokonaisuudesta, joista ensimmäinen käsittelee teorioita keskittyen OLI-paradigman ja suoran ulkomaisen investoinnin käsitteisiin. Seuraavat kolme osiota tutkivat tutkimuskysymyksiä, joista ensimmäisessä selvitetään monikansallisten yritysten vaikutusta Venäjän talouteen lähinnä suorien ulkomaisten investointien näkökulmasta. Kaksi viimeistä kappaletta käsittelevät, kuinka yritykset pääsevät Venäjälle ja millaisia etuja ja uhkia siellä toimimisesta on monikansallisille yrityksille. Näissä osioissa käsitellään erilaisia tapoja, joita yritykset käyttävät päästäkseen Venäjän markkinoille sekä millaisia seikkoja niiden täytyy huomioida tehdessään investointipäätöksen.

Pohjolan häät : kolminäytöksinen runo

J. H. Erkon näytelmät olivat raamatullisten ja kalevalaisten aiheiden pohjalta syntyneitä yhteiskunnallisia aatedraamoja. Pohjolan häät oli kirjoitettu Kansallisteatterin vihkijuhlaa varten 9. päiväksi huhtikuuta vuonna 1902. Näytelmässä on jyrkästi vastakkain kaksi valtaa, toinen vapaiden, orjuutta suvaitsemattomien kalevalaisten kansa, toinen Louhea sokeasti totteleva Pohjolan väki.

Methods and Models for Accelerating Dynamic Simulation of Fluid Power Circuits

The objective of this dissertation is to improve the dynamic simulation of fluid power circuits. A fluid power circuit is a typical way to implement power transmission in mobile working machines, e.g. cranes, excavators etc. Dynamic simulation is an essential tool in developing controllability and energy-efficient solutions for mobile machines. Efficient dynamic simulation is the basic requirement for the real-time simulation. In the real-time simulation of fluid power circuits there exist numerical problems due to the software and methods used for modelling and integration. A simulation model of a fluid power circuit is typically created using differential and algebraic equations. Efficient numerical methods are required since differential equations must be solved in real time. Unfortunately, simulation software packages offer only a limited selection of numerical solvers. Numerical problems cause noise to the results, which in many cases leads the simulation run to fail. Mathematically the fluid power circuit models are stiff systems of ordinary differential equations. Numerical solution of the stiff systems can be improved by two alternative approaches. The first is to develop numerical solvers suitable for solving stiff systems. The second is to decrease the model stiffness itself by introducing models and algorithms that either decrease the highest eigenvalues or neglect them by introducing steady-state solutions of the stiff parts of the models. The thesis proposes novel methods using the latter approach. The study aims to develop practical methods usable in dynamic simulation of fluid power circuits using explicit fixed-step integration algorithms. In this thesis, twomechanisms whichmake the systemstiff are studied. These are the pressure drop approaching zero in the turbulent orifice model and the volume approaching zero in the equation of pressure build-up. These are the critical areas to which alternative methods for modelling and numerical simulation are proposed. Generally, in hydraulic power transmission systems the orifice flow is clearly in the turbulent area. The flow becomes laminar as the pressure drop over the orifice approaches zero only in rare situations. These are e.g. when a valve is closed, or an actuator is driven against an end stopper, or external force makes actuator to switch its direction during operation. This means that in terms of accuracy, the description of laminar flow is not necessary. But, unfortunately, when a purely turbulent description of the orifice is used, numerical problems occur when the pressure drop comes close to zero since the first derivative of flow with respect to the pressure drop approaches infinity when the pressure drop approaches zero. Furthermore, the second derivative becomes discontinuous, which causes numerical noise and an infinitely small integration step when a variable step integrator is used. A numerically efficient model for the orifice flow is proposed using a cubic spline function to describe the flow in the laminar and transition areas. Parameters for the cubic spline function are selected such that its first derivative is equal to the first derivative of the pure turbulent orifice flow model in the boundary condition. In the dynamic simulation of fluid power circuits, a tradeoff exists between accuracy and calculation speed. This investigation is made for the two-regime flow orifice model. Especially inside of many types of valves, as well as between them, there exist very small volumes. The integration of pressures in small fluid volumes causes numerical problems in fluid power circuit simulation. Particularly in realtime simulation, these numerical problems are a great weakness. The system stiffness approaches infinity as the fluid volume approaches zero. If fixed step explicit algorithms for solving ordinary differential equations (ODE) are used, the system stability would easily be lost when integrating pressures in small volumes. To solve the problem caused by small fluid volumes, a pseudo-dynamic solver is proposed. Instead of integration of the pressure in a small volume, the pressure is solved as a steady-state pressure created in a separate cascade loop by numerical integration. The hydraulic capacitance V/Be of the parts of the circuit whose pressures are solved by the pseudo-dynamic method should be orders of magnitude smaller than that of those partswhose pressures are integrated. The key advantage of this novel method is that the numerical problems caused by the small volumes are completely avoided. Also, the method is freely applicable regardless of the integration routine applied. The superiority of both above-mentioned methods is that they are suited for use together with the semi-empirical modelling method which necessarily does not require any geometrical data of the valves and actuators to be modelled. In this modelling method, most of the needed component information can be taken from the manufacturer’s nominal graphs. This thesis introduces the methods and shows several numerical examples to demonstrate how the proposed methods improve the dynamic simulation of various hydraulic circuits.