Johtaja Erik Simons lokakuussa 1966

Kirje

The good Maxwell : den billiga och durabla vagnen för dagligt bruk

kuv., 23 x 16 cm

The good Maxwell : halpa ja hyvä vaunu jokapäiväistä käyttöä varten

kuv., 23 x 16 cm

Srategisen suunnittelun piirteitä yrityksen talousjohtamisessa: tapaustutkimus budjetoinnista

Tutkimuksen tavoitteena on ensiksi teoreettisesti tuoda esille miten budjetointia käytetään yrityksen strategisessa johtamisessa, ja sitten testata miten case-yritys soveltaa budjetointia strategiatyöskentelyssä. Case-tutkimuksen tulokset viittaavat vahvasti siihen, että budjettiensoveltamisroolit ovat samanlaisia kuin oli kuvattu teoriaosuudessa. Siksi suunnittelu-, toteuttamis- sekä valvontaroolit löytyivät case-yhtiöstä. Bonuksiin liittyvää budjettiharhaa ei voitu objektiivisesti löytää case-yhtiöstä. Kuitenkin kävi ilmi, että yhtiössä oli budjettiharhaa liittyen investointien tuottoarvioiden systemaattiseen minimointiin. Simonsin teoreettinen yrityksen johtamisen suorituskyvyn analysoinnin malli on käytössä case-yhtiössä koska yhtiö tekee pitkän aikavälin strategisen investointibudjetin. Investointiehdotuksia arvioidaan pääomantuottoasteen, markkinaosuuskehittymisen sekä nykyarvomenetelmän avulla. Case-tutkimus toi esille, että yksikönjohtajat haluavat enemmän päätösvaltaa ja riskinottoa, erityisesti investointibudjettia tehtäessä.

Modeling of non-isothermalvapor membrane separation with thermodynamic models and generalized mass transfer equations

A rigorous unit operation model is developed for vapor membrane separation. The new model is able to describe temperature, pressure, and concentration dependent permeation as wellreal fluid effects in vapor and gas separation with hydrocarbon selective rubbery polymeric membranes. The permeation through the membrane is described by a separate treatment of sorption and diffusion within the membrane. The chemical engineering thermodynamics is used to describe the equilibrium sorption of vapors and gases in rubbery membranes with equation of state models for polymeric systems. Also a new modification of the UNIFAC model is proposed for this purpose. Various thermodynamic models are extensively compared in order to verify the models' ability to predict and correlate experimental vapor-liquid equilibrium data. The penetrant transport through the selective layer of the membrane is described with the generalized Maxwell-Stefan equations, which are able to account for thebulk flux contribution as well as the diffusive coupling effect. A method is described to compute and correlate binary penetrant¿membrane diffusion coefficients from the experimental permeability coefficients at different temperatures and pressures. A fluid flow model for spiral-wound modules is derived from the conservation equation of mass, momentum, and energy. The conservation equations are presented in a discretized form by using the control volume approach. A combination of the permeation model and the fluid flow model yields the desired rigorous model for vapor membrane separation. The model is implemented into an inhouse process simulator and so vapor membrane separation may be evaluated as an integralpart of a process flowsheet.

Ion-exchange resins as stationary phase in reactive chromatography

Dynamic behavior of bothisothermal and non-isothermal single-column chromatographic reactors with an ion-exchange resin as the stationary phase was investigated. The reactor performance was interpreted by using results obtained when studying the effect of the resin properties on the equilibrium and kinetic phenomena occurring simultaneously in the reactor. Mathematical models were derived for each phenomenon and combined to simulate the chromatographic reactor. The phenomena studied includes phase equilibria in multicomponent liquid mixture¿ion-exchange resin systems, chemicalequilibrium in the presence of a resin catalyst, diffusion of liquids in gel-type and macroporous resins, and chemical reaction kinetics. Above all, attention was paid to the swelling behavior of the resins and how it affects the kinetic phenomena. Several poly(styrene-co-divinylbenzene) resins with different cross-link densities and internal porosities were used. Esterification of acetic acid with ethanol to produce ethyl acetate and water was used as a model reaction system. Choosing an ion-exchange resin with a low cross-link density is beneficial inthe case of the present reaction system: the amount of ethyl acetate as well the ethyl acetate to water mole ratio in the effluent stream increase with decreasing cross-link density. The enhanced performance of the reactor is mainly attributed to increasing reaction rate, which in turn originates from the phase equilibrium behavior of the system. Also mass transfer considerations favor the use ofresins with low cross-link density. The diffusion coefficients of liquids in the gel-type ion-exchange resins were found to fall rapidly when the extent of swelling became low. Glass transition of the polymer was not found to significantlyretard the diffusion in sulfonated PS¿DVB ion-exchange resins. It was also shown that non-isothermal operation of a chromatographic reactor could be used to significantly enhance the reactor performance. In the case of the exothermic modelreaction system and a near-adiabatic column, a positive thermal wave (higher temperature than in the initial state) was found to travel together with the reactive front. This further increased the conversion of the reactants. Diffusion-induced volume changes of the ion-exchange resins were studied in a flow-through cell. It was shown that describing the swelling and shrinking kinetics of the particles calls for a mass transfer model that explicitly includes the limited expansibility of the polymer network. A good description of the process was obtained by combining the generalized Maxwell-Stefan approach and an activity model that was derived from the thermodynamics of polymer solutions and gels. The swelling pressure in the resin phase was evaluated by using a non-Gaussian expression forthe polymer chain length distribution. Dimensional changes of the resin particles necessitate the use of non-standard mathematical tools for dynamic simulations. A transformed coordinate system, where the mass of the polymer was used as a spatial variable, was applied when simulating the chromatographic reactor columns as well as the swelling and shrinking kinetics of the resin particles. Shrinking of the particles in a column leads to formation of dead volume on top of the resin bed. In ordinary Eulerian coordinates, this results in a moving discontinuity that in turn causes numerical difficulties in the solution of the PDE system. The motion of the discontinuity was eliminated by spanning two calculation grids in the column that overlapped at the top of the resin bed. The reactive and non-reactive phase equilibrium data were correlated with a model derived from thethermodynamics of polymer solution and gels. The thermodynamic approach used inthis work is best suited at high degrees of swelling because the polymer matrixmay be in the glassy state when the extent of swelling is low.

Theoretical and numerical study of thermomagnetic convection in magnetic fluids

In this thesis, the magnetic field control of convection instabilities and heat and mass transfer processesin magnetic fluids have been investigated by numerical simulations and theoretical considerations. Simulation models based on finite element and finite volume methods have been developed. In addition to standard conservation equations, themagnetic field inside the simulation domain is calculated from Maxwell equations and the necessary terms to take into account for the magnetic body force and magnetic dissipation have been added to the equations governing the fluid motion.Numerical simulations of magnetic fluid convection near the threshold supportedexperimental observations qualitatively. Near the onset of convection the competitive action of thermal and concentration density gradients leads to mostly spatiotemporally chaotic convection with oscillatory and travelling wave regimes, previously observed in binary mixtures and nematic liquid crystals. In many applications of magnetic fluids, the heat and mass transfer processes including the effects of external magnetic fields are of great importance. In addition to magnetic fluids, the concepts and the simulation models used in this study may be applied also to the studies of convective instabilities in ordinary fluids as well as in other binary mixtures and complex fluids.

Comprehensive Study of Crystal Growth from Solution

Crystal growth is an essential phase in crystallization kinetics. The rate of crystal growth provides significant information for the design and control of crystallization processes; nevertheless, obtaining accurate growth rate data is still challenging due to a number of factors that prevail in crystal growth. In industrial crystallization, crystals are generally grown from multi-componentand multi-particle solutions under complicated hydrodynamic conditions; thus, it is crucial to increase the general understanding of the growth kinetics in these systems. The aim of this work is to develop a model of the crystal growth rate from solution. An extensive literature review of crystal growth focuses on themodelling of growth kinetics and thermodynamics, and new measuring techniques that have been introduced in the field of crystallization. The growth of a singlecrystal is investigated in binary and ternary systems. The binary system consists of potassium dihydrogen phosphate (KDP, crystallizing solute) and water (solvent), and the ternary system includes KDP, water and an organic admixture. The studied admixtures, urea, ethanol and 1-propanol, are employed at relatively highconcentrations (of up to 5.0 molal). The influence of the admixtures on the solution thermodynamics is studied using the Pitzer activity coefficient model. Theprediction method of the ternary solubility in the studied systems is introduced and verified. The growth rate of the KDP (101) face in the studied systems aremeasured in the growth cell as a function of supersaturation, the admixture concentration, the solution velocity over a crystal and temperature. In addition, the surface morphology of the KDP (101) face is studied using ex situ atomic force microscopy (AFM). The crystal growth rate in the ternary systems is modelled on the basis of the two-step growth model that contains the Maxwell-Stefan (MS) equations and a surface-reaction model. This model is used together with measuredcrystal growth rate data to develop a new method for the evaluation of the model parameters. The validation of the model is justified with experiments. The crystal growth rate in an imperfectly mixed suspension crystallizer is investigatedusing computational fluid dynamics (CFD). A solid-liquid suspension flow that includes multi-sized particles is described by the multi-fluid model as well as by a standard k-epsilon turbulence model and an interface momentum transfer model. The local crystal growth rate is determined from calculated flow information in a diffusion-controlled crystal growth regime. The calculated results are evaluated experimentally.

IT-palveluiden ulkoistaminen -transaktiokustannusteoreettinen tapaustutkimus

Tutkielman tavoitteena on selvittää, mitä IT-palveluita ja miten yrityksen kannattaa ulkoistaa sekä arvioida ulkoistamiseen liittyviä välillisiä kustannuksia. Tutkimuksen teoreettisen taustan muodostavat transaktiokustannusteoria ja Simonsin päätöksentekomallista johdettu IT-palveluiden ulkoistamisprosessia kuvaava malli. Empiirisessä osassa käytetään esimerkkinä yritystä, joka on valikoivasti ulkoistanut IT-palveluitaan. Ulkoistamistapauksista kerättiin tietoja teemahaastatteluin. Tutkielman tulosten mukaan onnistuneen IT-palvelun ulkoistamisen tekijöitä ovat pohjatyön tekeminen ja vertailupohjan rakentaminen, sopimuksen tarkkuus, toimittajan toiminnan mittaaminen sekä IT-osaston välittävän roolin huomioiminen sopimuksen jälkeisessä toiminnassa.

Myten om det rationella flödet : en studie av hur organisatorisk ledning formas genom omvärldsanalys och underrättelsearbete i kunskapsintensiva företagsmiljöer

Omvärldsanalys, omvärldsbevakning, competitive intelligence och business intelligence är begrepp i tiden. De används för att beskriva en växande yrkespraktik som spanar efter och analyserar omvärldsinformation. I stort sett samtliga större företag har idag infört ett organiserat underrättelsearbete (OUA), men praktiken inskränker sig inte till kommersiell verksamhet utan återfinns även till exempel i kommunal förvaltning och flertalet statliga myndigheter. I sin avhandling, Myten om det rationella flödet, beskriver Magnus Hoppe hur organiserat underrättelsearbete anpassas till olika situationer men också hur det påverkar organisationers strategi och utveckling. Samtidigt riktar Hoppe skarp kritik mot en övertro på rationalitet i organisationer och beskriver hur denna övertro vidmakthåller föråldrade idéer om hur ett väl fungerande underrättelsearbete bör organiseras och verka. Förutom beskrivning och kritik av de i dagsläget dominerande teorierna om organiserat underrättelsearbete, knyter Hoppe ihop sitt ämne med ett urval organisationsteoretiska teman som kretsar kring ledarskap och beslutsfattande. Därutöver formar han flera egna modeller i en reflekterande text om hur informationsurval, analytiska processer samt sociala kontakter påverkar organisationsmedlemmars uppfattningar om den egna organisationen, den värld de befinner sig i, men inte minst sin egen position. Ett återkommande konstaterande är att det inte går, som många populärt hållna böcker gör gällande, att skapa ett rationellt informationsflöde från omvärlden in i organisationens beslutsfattande processer. För detta är den inomorganisatoriska miljön alltför komplex, hävdar Hoppe, som stöder sina tankar på intervjuer med underrättelsearbetare vid fyra internationellt verksamma företag. Idén om det rationella informationsflödet är en myt som hindrar oss från att se hur organiserat underrättelsearbete faktiskt går till, argumenterar han. Men det innebär inte samtidigt att myten lätt låter sig avtäckas eller avfärdas. Istället är myten en del av vår kollektiva tro på organisationer som rationella och kontrollerbara samhällsaktörer. Med ett organiserat underrättelsearbete skapas förvisso goda förutsättningar för ett mer insiktsfullt beslutsfattande, men underrättelsearbetet gör också att de organisationer som tar det till sig framstår som rationellt styrda och omvärldsanpassade. Något som dagens organisationer och beslutfattare har ett stort behov av att kunna hävda. Organiserat underrättelsearbete innebär inte automatiskt att vare sig beslut eller ledning blir bättre, men det ger sken av det. Hoppe avslutar avhandlingen med att gå bortom myten då han beskriver organiserat underrättelsearbete som format av en kompletterande logik - att bidra till ett framväxande koordinerat handlande, där beslut vare sig behöver vara uttalade eller ens nödvändiga. Genom att påverka informationsurval och delta i analytiska processer på skiftande underrättelsearenor intar underrättelsearbetare en central roll i den interna kampen om hur omvärlden bör tolkas och därmed vad som tänks och görs i organisationens namn. Granskningsmannen, tillika opponenten, docent Bengt Gustavsson skriver i sitt utlåtande att "Kritiken mot rationalitet i organisationer har funnits sedan länge i organisationsteorin, inte minst sedan Herbert Simons dagar, men disputanden stannar inte vid denna kritik utan använder den för att lyfta fram alternativa fenomen och funktioner som han funnit genom sina undersökningar, t.ex. betydelser av sociala kontakter och småprat i underrättelsearbetet [...]; OUA som ideologisk agent i formandet av organisatoriskt tänkande; OUA som redskap för organisationens medlemmar att transcendera tid, rum och ego; och t.o.m. OUA som organiseringsprincip." Den andre granskningsmannen, professor Sven Hamrefors som i flera studier undersökt organisationers omvärldsbevakning, gör en kompletterande bedömning och lyfter fram att "Forskningsfrågan är relevant och angelägen" och "ett välkommet bidrag till att skapa en relation mellan idealet och verkligheten, vilket definitivt kommer att få ett genomslag på utvecklingen av kunskapsområdet." Hamrefors poängterar också att "det var länge sedan jag läste en så välformulerad svensk text", vilket borgar för att Hoppe når sitt mål att få fler än bara forskarkollektivet att ta till sig avhandlingens poänger och därmed lyckas synliggöra fenomenet, vilket är hans primära syfte. Organiserat underrättelsearbete är en verksamhet som vi fram till idag endast haft bristfällig kunskap om. Med Hoppes avhandling ändras läget, och vi kan nu utveckla en mer insiktsfull diskussion om vad detta växande fenomen innebär för både organisationer och samhälle.

Ilmastokeskustelun ruumiinavaus

Kirjallisuusarvostelu

Side peaks in Nb and NbTi point-contact spectra

Superconductor – normal metal point contacts were investigated, using different combinations of Cu, brass, Nb and NbTi. The resulting spectra contained side peaks. The currents at which these side peaks appeared, depended on the radii of the contacts. For contacts with Nb this dependence was quadratic, while for contacts with NbTi it was linear. Based on this, we argue that the side peaks in the case of the Nb contacts are due to the critical current density being exceeded. In contrast, side peaks of the NbTi contacts are caused by the self-magnetic field exceeding the lower critical field of NbTi. The NbTi contacts did not show the expected contribution from the vanishing Maxwell resistance of the superconductor, a question which remained open.