Efficient estimation of blocking probabilities in non-stationary loss networks

This paper considers estimation of blocking probabilities in a nonstationary loss network. Invoking the so called MOL (Modified Offered Load) approximation, the problem is transformed into one requiring the solution of blocking probabilities in a sequence of stationary loss networks with time varying loads. To estimate the blocking probabilities Monte Carlo simulation is used and to increase the efficiency of the simulation, we develop a likelihood ratio method that enables samples drawn at a one time point to be used at later time points. This reduces the need to draw new samples every time independently as a new time point is considered, thus giving substantial savings in the computational effort of evaluating time dependent blocking probabilities. The accuracy of the method is analyzed by using Taylor series approximations of the variance indicating the direct dependence of the accuracy on the rate of change of the actual load. Finally, three practical applications of the method are provided along with numerical examples to demonstrate the efficiency of the method

Population ageing and fiscal sustainability in Finland: a stochastic analysis

This study analyses the fiscal sustainability of the Finnish public sector using stochastic projections to describe uncertain future demographic trends and asset yields. While current tax rates are unlikely to yield sufficient tax revenue to finance public expenditure with an ageing population, if developments are as expected, the problem will not be very large. However, there is a small, but not negligible, probability that taxes will need to be raised dramatically, perhaps by over 5 percentage points. Such outcomes, if realised, could destabilise the entire welfare state. The study also analyses three policy options aimed at improving sustainability. Longevity adjustment of pension benefits and introduction of an NDC pension system would reduce the expected problem and narrow the sustainability gap distribution. Under the third option, pension funds would invest more in equities and expect to get higher returns. This policy also limits the sustainability problem, but only under precondition that policymakers in the future can live with substantially larger variation in the value of the funds without adjusting tax rules or benefits.public finance; fiscal sustainability; uncertainty; stochastic simulations

Reduced formulation of a steady fluid-structure interaction problem with parametric coupling

We propose a two-fold approach to model reduction of fluid-structure interaction. The state equations for the fluid are solved with reduced basis methods. These are model reduction methods for parametric partial differential equations using well-chosen snapshot solutions in order to build a set of global basis functions. The other reduction is in terms of the geometric complexity of the moving fluid-structure interface. We use free-form deformations to parameterize the perturbation of the flow channel at rest configuration. As a computational example we consider a steady fluid-structure interaction problem: an incmpressible Stokes flow in a channel that has a flexible wall.Comment: 10 pages, 3 figure

Longevity adjustment of pension benefits

In anticipation of future gains in life expectancy, several countries have passed laws that automatically adjust pensions, if life expectancy changes. In this paper we study the effects of longevity adjustment under demographic uncertainty in Finland. If longevity increases, the adjustment decreases the contribution rate, and the reduction is bigger the higher the rate would have been without the reform. On the other hand, longevity adjustment increases the uncertainty in replacement rates. The current middle-aged generations, whose pensions are reduced more than contributions, are likely to experience the largest losses. The full gains are observed far in future. The quantitative results depend on, besides demographic realisations, the specifics of the pension system. Longevity adjustment significantly weakens the defined-benefit nature of the Finnish pension system and brings in a strong defined-contribution flavour.• How well do the academic resources, company R&D investments and research needs converge to help secure the future competitiveness of the Finnish forest industries

Computationally designed variants of Escherichia coli chorismate mutase show altered catalytic activity

Computational protein design methods were used to predict five variants of monofunctional Escherichia coli chorismate mutase expected to maintain catalytic activity. The variants were tested experimentally and three active site mutants exhibited catalytic activity similar to or greater than the wild-type enzyme. One mutant, Ala32Ser, showed increased catalytic efficiency

Longevity Risk and Taxation of Public Pensions

We study transitions from EET tax regime to TEE regime in a defined-benefit pension scheme with a numerical overlapping generations model, using stochastic mortality projections as inputs. In a traditional pension scheme with no automatic longevity rules, such as a link between life expectancy and pensions or retirement age, the tax regime shift can be used to improve public finances, when longevity increases. Diminished private saving and weaker labour supply incentives are among the downsides. Especially the latter makes the reform welfare-reducing, if the improvement in state finances is not used to relieve taxation of labour

Enhanced resin-composite bonding to zirconia framework after pretreatment with selected silane monomers

Objective: To evaluate the effect of five experimental silane monomer primers in vitro on the shear bond strength of a phosphate ester resin-composite cement bonded to a silicatized zirconia framework. Methods: A total of 144 planar zirconia (Procera AllZircon) specimens were subjected to tribochemical silica treatment, randomly divided into 12 sub-groups (n = 12), and silanized with 1.0% (v/v) activated solutions of 3-acryloxypropyltrimethoxysilane, 3 glycidoxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, styrylethyltrimethoxysilane, and 3-isocyanatopropyltriethoxysilane, which had been prepared in 95% ethanol (pH 4.5). A ready-to-use 3- methacryloxypropyltrimethoxysilane (RelyX™ Ceramic Primer) was used as the control. One resincomposite cement (RelyX™ Unicem) stub was bonded to each silicatized and silanized zirconia specimen. Half of the specimen groups were dry-tested and half were thermo-cycled at 6000 cycles between 5 °C and 55 °C, with a constant dwelling time of 30 s. The shear bond strengths of the cement stubs bonded to zirconia were measured using a universal testing machine using a constant cross-head speed of 1 mm/min. The silane primer activation was evaluated using Fourier-transform infrared spectroscopy. Results: The highest shear bond strength was obtained for 3- acryloxypropyltrimethoxysilane in dry storage, 11.7 MPa (SD, 2.3 MPa) and after thermo-cycling 17.6 (4.1) MPa for glycidoxypropyltrimethoxysilane. The lowest shear bond strength values were obtained with control silane: in dry storage, 4.5 (1.3) MPa, after thermo-cycling 6.5 (2.6) MPa. Thermo-cycling increased the bond strengths significantly (ANOVA, p < 0.001) and differently for each type of silane (ANOVA, p < 0.001). Significance: Silanization with five experimental silane primers in vitro produced significantly greater shear bond strengths than the ready-to-use control silane. © 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.postprin

Back to the Roots : Aloittavien matkailualan opiskelijoiden ryhmäytyminen tapahtumassa

Tämän produktityyppisen opinnäytetyön tarkoituksena oli saada aloittavat opiskelijat ryhmäytymään keskenään mukavien aktiviteettien, hyvän ruoan sekä rauhallisen live-musiikin avulla. Tapahtuman toimeksiantaja oli HAAGA-HELIA Porvoo Campus, jolle pyrittiin suunnittelemaan mahdollisimman hyvä tapahtuma, joka antaisi toimeksiantajalle toteuttamiskelpoisia kehitysehdotuksia, sekä olla mahdollisille tuleville tapahtuman järjestäjille esimerkkinä. Kohderyhmä koostui aloittaneista matkailun opiskelijoista, sekä kansainvälisistä liiketalouden opiskelijoista. Opiskelijoita tapahtumaan osallistui yhteensä 29. Opinnäytetyön teoreettinen osuus koostuu projektin määritelmästä ja sen osa-alueista, tapahtuman järjestämisestä sekä ryhmän ohjaamisesta. Myöhemmin toiminnallisessa osassa raportoidaan toteutusvaiheen ideointi, prosessi sekä lopetusvaihe. Tapahtuman suunnittelu on aloitettu syyskuussa 2011 ja sen toteutus on helmikuussa 2012. Tapahtuma pitää sisällään ulkona järjestettävää ryhmäytymistä edistävää toimintaa Porvoon Stensbölen partiolaistalossa. Tapahtuma koostuu viidestä rastitehtävästä, buffet-ruokailusta sekä live-musiikista. Tapahtuma oli kokonaisuudessaan onnistunut, vaikka osallistujamäärä jäi suunniteltua pienemmäksi. Palaute oli pääosin positiivista ja osallistujat olivat sen mukaan tyytyväisiä tapahtuman sisältöön. Tapahtuman tavoitetta ajatellen opiskelijat saatiin hyvin ryhmäytymään sekä tutustumaan toisiinsa. Projektissa kehitettävät asiat olivat aikataulutus, projektiorganisaatio sekä osa projektin suunnittelussa huomioon otettavista asioista. Erityisesti markkinointi, sekä osallistujien sitouttaminen tapahtumaamme osoittautui kehitystä vaativaksi osioksi.The main objective of this thesis was to organize an event that would help the freshmen to get to know each other better by doing some funny activities, enjoying good food and listening to calm music. Back to The Roots –event was commissioned by Porvoo Campus, HAAGA-HELIA University of Applied Sciences. As well as Campus would get some valuable information from the results, the main goal was to organize a fun and useful event for the students taking part. The target-market was the freshmen from Finnish tourism program and international business students. The theoretical framework includes the concepts of definition of a project and the parts that project includes, organizing an event and group formation and leading. Later on the functional part of the thesis there is discussion about planning the project, implementation and ending process of the event. The planning of this event started on September 2011 and it will be held on February 2012. The main points of the event will be five different kinds of activities check points, buffet lunch and live music. The event in general was successful although the amount of participants was smaller than intented. Feedback was mainly positive and the students were satisfied with the content of the event. From the targets point of view the students got to know each other better and they managed to cluster with each other successfully. Matters to improve in the project were scheduling, project organization and some of the things to consider when planning a project. Especially marketing and committing the customers to the event turned out to be fields that still need enhancing