Towards input/output-free modelling of linear infinite-dimensional systems in continuous time

This dissertation describes a networking approach to infinite-dimensional systems theory, where there is a minimal distinction between inputs and outputs. We introduce and study two closely related classes of systems, namely the state/signal systems and the port-Hamiltonian systems, and describe how they relate to each other. Some basic theory for these two classes of systems and the interconnections of such systems is provided. The main emphasis lies on passive and conservative systems, and the theoretical concepts are illustrated using the example of a lossless transfer line. Much remains to be done in this field and we point to some directions for future studies as well.

The solutions and tunneling properties for a linear potential and an inverted harmonic oscillator in an infinite well

In this work we look at two different 1-dimensional quantum systems. The potentials for these systems are a linear potential in an infinite well and an inverted harmonic oscillator in an infinite well. We will solve the Schrödinger equation for both of these systems and get the energy eigenvalues and eigenfunctions. The solutions are obtained by using the boundary conditions and numerical methods. The motivation for our study comes from experimental background. For the linear potential we have two different boundary conditions. The first one is the so called normal boundary condition in which the wave function goes to zero on the edge of the well. The second condition is called derivative boundary condition in which the derivative of the wave function goes to zero on the edge of the well. The actual solutions are Airy functions. In the case of the inverted oscillator the solutions are parabolic cylinder functions and they are solved only using the normal boundary condition. Both of the potentials are compared with the particle in a box solutions. We will also present figures and tables from which we can see how the solutions look like. The similarities and differences with the particle in a box solution are also shown visually. The figures and calculations are done using mathematical software. We will also compare the linear potential to a case where the infinite wall is only on the left side. For this case we will also show graphical information of the different properties. With the inverted harmonic oscillator we will take a closer look at the quantum mechanical tunneling. We present some of the history of the quantum tunneling theory, its developers and finally we show the Feynman path integral theory. This theory enables us to get the instanton solutions. The instanton solutions are a way to look at the tunneling properties of the quantum system. The results are compared with the solutions of the double-well potential which is very similar to our case as a quantum system. The solutions are obtained using the same methods which makes the comparison relatively easy. All in all we consider and go through some of the stages of the quantum theory. We also look at the different ways to interpret the theory. We also present the special functions that are needed in our solutions, and look at the properties and different relations to other special functions. It is essential to notice that it is possible to use different mathematical formalisms to get the desired result. The quantum theory has been built for over one hundred years and it has different approaches. Different aspects make it possible to look at different things.

The solutions and tunneling properties for a linear potential and an inverted harmonic oscillator in an infinite well

In this work we look at two different 1-dimensional quantum systems. The potentials for these systems are a linear potential in an infinite well and an inverted harmonic oscillator in an infinite well. We will solve the Schrödinger equation for both of these systems and get the energy eigenvalues and eigenfunctions. The solutions are obtained by using the boundary conditions and numerical methods. The motivation for our study comes from experimental background. For the linear potential we have two different boundary conditions. The first one is the so called normal boundary condition in which the wave function goes to zero on the edge of the well. The second condition is called derivative boundary condition in which the derivative of the wave function goes to zero on the edge of the well. The actual solutions are Airy functions. In the case of the inverted oscillator the solutions are parabolic cylinder functions and they are solved only using the normal boundary condition. Both of the potentials are compared with the particle in a box solutions. We will also present figures and tables from which we can see how the solutions look like. The similarities and differences with the particle in a box solution are also shown visually. The figures and calculations are done using mathematical software. We will also compare the linear potential to a case where the infinite wall is only on the left side. For this case we will also show graphical information of the different properties. With the inverted harmonic oscillator we will take a closer look at the quantum mechanical tunneling. We present some of the history of the quantum tunneling theory, its developers and finally we show the Feynman path integral theory. This theory enables us to get the instanton solutions. The instanton solutions are a way to look at the tunneling properties of the quantum system. The results are compared with the solutions of the double-well potential which is very similar to our case as a quantum system. The solutions are obtained using the same methods which makes the comparison relatively easy. All in all we consider and go through some of the stages of the quantum theory. We also look at the different ways to interpret the theory. We also present the special functions that are needed in our solutions, and look at the properties and different relations to other special functions. It is essential to notice that it is possible to use different mathematical formalisms to get the desired result. The quantum theory has been built for over one hundred years and it has different approaches. Different aspects make it possible to look at different things.

Väsymismitoitusperusteiden ja kuormitusten määrittäminen hitsatuille sekoitinakseleille

Työssä selvitettiin vastusvenymäliuskamittausten avulla sekoitinakselin kuormitukset sekä perehdyttiin väsymisilmiöön ja hitsattujen rakenteiden väsymismitoitukseen. Kuormitusten mittauksessa rekisteröitiin akselin kriittisen kohdan taivutus- ja vääntövenymät. Mittaustulosten avulla tutkittiin kuormituksia ja kuormitusten luonnetta sekä johdettiin väsymismitoitusperusteet sekoitinakseleille. Väsymismitoitus perustuu kahteen eri menetelmään. Vakioamplitudiseen väsymisrajaan perustuvassa menetelmässä vaihtuva-amplitudisella jännityksellä suurinkin jännitysheilahdus jää väsymisrajan alle. Kokonaisväsymisvaurioon perustuvassa mitoituksessa puolestaan sallitaan vakioamplitudisen väsymisrajan ylitys. Kestoikä on käytetty loppuun, kun väsymisvaurio saavuttaa väsymiskestävyyden arvon. Menetelmän valinta riippuu käytettävästä sekoitinelintyypistä ja käytön aikana ilmenevistä väsymisen kannalta vaarallisista tilanteista.

On the Application of Beam on Elastic Foundation Theory to the Analysis of Stiffened Plate Strips

The main objective of this thesis is to show that plate strips subjected to transverse line loads can be analysed by using the beam on elastic foundation (BEF) approach. It is shown that the elastic behaviour of both the centre line section of a semi infinite plate supported along two edges, and the free edge of a cantilever plate strip can be accurately predicted by calculations based on the two parameter BEF theory. The transverse bending stiffness of the plate strip forms the foundation. The foundation modulus is shown, mathematically and physically, to be the zero order term of the fourth order differential equation governing the behaviour of BEF, whereas the torsion rigidity of the plate acts like pre tension in the second order term. Direct equivalence is obtained for harmonic line loading by comparing the differential equations of Levy's method (a simply supported plate) with the BEF method. By equating the second and zero order terms of the semi infinite BEF model for each harmonic component, two parameters are obtained for a simply supported plate of width B: the characteristic length, 1/ λ, and the normalized sum, n, being the effect of axial loading and stiffening resulting from the torsion stiffness, nlin. This procedure gives the following result for the first mode when a uniaxial stress field was assumed (ν = 0): 1/λ = √2B/π and nlin = 1. For constant line loading, which is the superimposition of harmonic components, slightly differing foundation parameters are obtained when the maximum deflection and bending moment values of the theoretical plate, with v = 0, and BEF analysis solutions are equated: 1 /λ= 1.47B/π and nlin. = 0.59 for a simply supported plate; and 1/λ = 0.99B/π and nlin = 0.25 for a fixed plate. The BEF parameters of the plate strip with a free edge are determined based solely on finite element analysis (FEA) results: 1/λ = 1.29B/π and nlin. = 0.65, where B is the double width of the cantilever plate strip. The stress biaxial, v > 0, is shown not to affect the values of the BEF parameters significantly the result of the geometric nonlinearity caused by in plane, axial and biaxial loading is studied theoretically by comparing the differential equations of Levy's method with the BEF approach. The BEF model is generalised to take into account the elastic rotation stiffness of the longitudinal edges. Finally, formulae are presented that take into account the effect of Poisson's ratio, and geometric non linearity, on bending behaviour resulting from axial and transverse inplane loading. It is also shown that the BEF parameters of the semi infinite model are valid for linear elastic analysis of a plate strip of finite length. The BEF model was verified by applying it to the analysis of bending stresses caused by misalignments in a laboratory test panel. In summary, it can be concluded that the advantages of the BEF theory are that it is a simple tool, and that it is accurate enough for specific stress analysis of semi infinite and finite plate bending problems.

Lyssnande : en vårdvetenskaplig betraktelse

Denna vårdvetenskapliga studie har sökarljuset riktat mot lyssnande som något fundamentalt för människan. Studiens syfte är att utifrån forskarens traditionstillhörighet och en klart uttalad teorikärna, värdegrund, ontologisk grund samt en hermeneutisk ansats avtäcka nytt inseende om vad lyssnande är samt vad som är vårdande i lyssnande. Studiens avsikt är att bringa ontologisk klarhet, klargöra lyssnandets plats inom vårdvetenskaplig teoribildning samt bidra med bilder av det vårdande med relevans för klinisk praxis. Det hermeneutiska arbetssättet är en ständig rörelse mellan det enskilda och gemensamma. Den vårdvetenskapliga traditionens grundläggande ordning utgör siktet för kunskapssökandet samtidigt som det är gentemot den caritativa vårdteorin som nytt inseende ur historiska källor reflekteras för att lysa upp och synliggöra det evidenta och ursprungliga om lyssnande. Begreppsutredningen av lyssna som begrepp ger förståelse för begreppets historiska ursprung och dess starka band med begreppen lyss, lystra, lyda, följa, iaktta, se samt lust, begär, böjelse och glädje. Läsning och begrundan av filosoferna Bubers, Lévinas och författaren Dostojevskijs livsverk avtäcker vittnesbörd och stillbilder som tolkas för att synliggöra tolkningsantaganden om lyssnandets väsen och gestaltning. Jag har läst och begrundat texterna med öppenhet, lyhördhet och en kvardröjande hållning för att låta dem beröra, tilltala mig och framträda som något nytt. Ur de enskilda texterna avtäcks mönster av en gemensam inre ordning och en gemensam stillbild och tolkningsantaganden om lyssnande formas. När den gemensamma inre ordningen får sammanstråla med studiens vårdvetenskapliga grund synliggörs en urbild och teser om lyssnande samt det vårdande i lyssnande. Avtäckandet visar att lyssnande är en grundhållning till livet självt. Människan lyssnar till sitt innersta väsen för att tillägna sig en inre grundordning samt hörsamma sin tillhörighet i en mera allomfattande gemenskap till den skapande, den andre och det oändliga. I ljuset av kärlekens kraft och bejakandet av mänskligt lidande kan ensamhet och gemenskap sluta förbund med varandra i en mellanverklighet som bär oändlighetens och evighetens kännetecken, och som får toner av det heliga och eviga att ljuda i allt och alla i en närvaro här och nu. Lyssnande är en väsenshandling som uttalas genom en vårdande hållning att tjäna, offra och bära ansvar för den andre med medmänsklig barmhärtighet och medmänskligt medlidande. Band till den andre knyts genom den egna sårbarheten och genom att med ödmjukhet, äkthet och gästfrihet bjuda in och välkomna den andre i sin annanhet. Den vårdande gemenskapen skapar en rörelse som bär på en livsbringande kraft genom vilken människan uppnår frihet att varda, finna näring och försoning.

Kestomagneettikoneen roottorin väsymisanalyysi

Työn tavoitteena oli luoda työkalu kestomagneettikoneiden roottoreiden väsymisen analysointia varten. Työkalu toteutettiin siten, että siihen voidaan liittää oikeasta koneesta mitattu kuormitusdata, sekä tarvittavat materiaalitiedot. Kuormitusdata muunnetaan työkalussa jännityshistoriaksi käyttämällä elementtimenetelmän avulla laskettavaa skaalauskerrointa. Kestoiän laskemiseen analyysityökalu käyttää jännitykseen perustuvaa menetelmää sekä rainflowmenetelmää ja Palmgren-Minerin kumulatiivista vauriosääntöä. Lisäksi työkalu tekee tutkittavalle tapaukselle Smithin väsymislujuuspiirroksen. Edellä mainittujen menetelmien lisäksi työn teoriaosassa esiteltiin väsymisanalyysimenetelmistä myös paikalliseen venymään perustuva menetelmä sekä murtumismekaniikka. Nämä menetelmät jäivät monimutkaisuutensa vuoksi toteuttamatta työkalussa. Väsymisanalyysityökalulla laskettiin kestoiät kahdelle esimerkkitapaukselle. Kummassakin tapauksessa saatiin tulokseksi ääretön kestoikä, mutta aksiaalivuokoneen roottorin dynaaminen varmuus oli pieni. Vaikka tulokset vaikuttavat järkeviltä, ne olisi vielä hyvä verifioida esimerkiksi kaupallisen ohjelmiston avulla täyden varmuuden saamiseksi.

Yhdysvaltojen ja koalition joukkojen tappiot Afganistanin sodassa 19.10.2001 - 31.12.2009

Työn aiheena on Yhdysvaltojen ja koalition joukkojen tappiot Afganistanin sodassa 2001 – 2009. Syyskuun 2001 terrori-iskujen jälkeen Yhdysvallat aloittivat sotilaalliset operaatiot Afganistanissa nopeasti. Aluksi operaatio sai nimen ”Infinite Justice”, joka melko pian muutettiin ”Enduring Freedomiksi”. Afganistanin operaation alkuperäisenä tavoitteena oli vaihtaa Afganistanin hallinto ja tuhota maassa olevat Al-Qaidan ja Talibanin aseellisetvoimat. Nämä tavoitteet saavutettiin varsin nopeasti. Vuoteen 2002 loppuun mennessä Taliban ja Al- Qaida oli sotilaallisesti lyöty Afganistanissa. Tärkeimpiä johtohenkilöitä ei kuitenkaan saatu eliminoitua ja tappion ollessa varma Talibanin ja Al-Qaidan edustajat siirtyivät heimoalueelle Pakistaniin. Vuodesta 2003 alkaen Afganistanin sotaa voidaan pitää kumouksellisena sotana, jossa kapinalliset yrittävät kukistaa vallalla olevan hallinnon. Kuten monissa muissakin kumouksellisissa sodissa myös Afganistanissa on käynyt niin, että sieltä irtautuminen on muodostunut ongelmaksi. Operaation pitkittyessä, se vaati kokoajan lisää resursseja.

Serva ad ministrare : tjänandets ethos i vårdledarskap

Avhandlingen syftar till att ur ett vårdvetenskapligt perspektiv beskriva och upptäcka tjänandets meningsinnehåll samt fördjupa förståelsekunskap om tjänandets ethos i förhållande till vårdledarskap med en inriktning på det vårdadministrativa. Syftet är även att skapa en idealmodell som öppnar för en ny eller annorlunda förståelsehorisont för tjänandets ethos i vårdledarskap. Kunskapssökandet sker genom följande delstudier: (1) I begreppsbestämningen genomförs begreppsanalyser av tjäna och tjänst med avsikt att öppna för en grundförståelse och tankestruktur i forskningsuppgiften. (2) I det idéhistoriska spåras tjänandets ontologiska arv och idémönster fram genom tolkning av historiska källornas texter från 1900-talets första hälft i ljuset av sjuksköterskeledarskap utgående från Sophie Mannerheims, Bertha Wellins och Bergljot Larssons idéer och tankeströmningar. (3) Sökandet fortsätter i dagens kliniska kontextbas genom kvalitativa djupintervjuer med 30 deltagare (vårdledare och vårdare) från Finland, Sverige och Norge. Förförståelsen och forskningens teoretiska perspektiv har rötter i Erikssons caring science-tradition och vårdvetenskapens ontologiska grundantaganden som utvecklats vid Åbo Akademi, Enheten för vårdvetenskap i Vasa. Forskningsansatsen är inspirerad av H-G Gadamers filosofiska hermeneutik. Designen är explorativ-deskriptiv, idiografisk och implicerar ett hypotetisk-deduktivt tillvägagångssätt. Tjänandet och vårdledarskapets ethos upptäcks och tolkas genom det metodologiska närmandet: Erikssons hermeneutiska begreppsbestämningsmodell, idéhistoriska läsakt och hermeneutiska läsakt. Materialet bildar förståelsehorisonter genom den hermeneutiska dialogens successiva och oändliga rörelse. Horisonterna reflekteras mot teorikärnan för att öppna för ny förståelse av tjänandets meningsinnehåll, vårdledarskap och vårdadministration. I slutandet sker en horisontsammansmältning och en reflektiv anslutning till vårdvetenskapens teorikärna som visar hur tjänandets ethos blir evident i vårdledarskap. Resultatet visar att vårdledarskap som är tjänande för patienten och vårdkulturen synliggörs i vårdadministrationens kontext genom huvudets skärpa, handens gärningar och hjärtats visdom. Tjänandets sanna, goda och sköna tidlösa rörelse är riktad mot hälsa och helande. I dag sammankopplas tjänande inom vårdorganisationer med hälsoekonomiska förhållanden, effektivitet, produktivitet och rationalitet, vilket strider mot tjänandets värdegrund, människans värdighet och respekt för livet. Vårdorganisationernas etiska ansvar är att fungera som samhälleliga förebilder, tillrättalägga för vårdadministrationernas tjänande och stå i patientens tjänst. Gestaltningen av tjänandets ethos i vårdledarskap öppnar för nya diskurser, riktningar, visioner och handlingar i den vårdadministrativa verkligheten. Avhandlingen ger vårdvetenskapens systematiska grundforskning ett teoritillskott av fördjupad förståelse av tjänandets och vårdledarskapets historiska och samtida ontologiska evidens och ethos med applikationen på klinisk vårdvetenskap.

Stiffness based trajectory planning and feedforward based vibration suppression control of parallel robot machines

The dissertation proposes two control strategies, which include the trajectory planning and vibration suppression, for a kinematic redundant serial-parallel robot machine, with the aim of attaining the satisfactory machining performance. For a given prescribed trajectory of the robot's end-effector in the Cartesian space, a set of trajectories in the robot's joint space are generated based on the best stiffness performance of the robot along the prescribed trajectory. To construct the required system-wide analytical stiffness model for the serial-parallel robot machine, a variant of the virtual joint method (VJM) is proposed in the dissertation. The modified method is an evolution of Gosselin's lumped model that can account for the deformations of a flexible link in more directions. The effectiveness of this VJM variant is validated by comparing the computed stiffness results of a flexible link with the those of a matrix structural analysis (MSA) method. The comparison shows that the numerical results from both methods on an individual flexible beam are almost identical, which, in some sense, provides mutual validation. The most prominent advantage of the presented VJM variant compared with the MSA method is that it can be applied in a flexible structure system with complicated kinematics formed in terms of flexible serial links and joints. Moreover, by combining the VJM variant and the virtual work principle, a systemwide analytical stiffness model can be easily obtained for mechanisms with both serial kinematics and parallel kinematics. In the dissertation, a system-wide stiffness model of a kinematic redundant serial-parallel robot machine is constructed based on integration of the VJM variant and the virtual work principle. Numerical results of its stiffness performance are reported. For a kinematic redundant robot, to generate a set of feasible joints' trajectories for a prescribed trajectory of its end-effector, its system-wide stiffness performance is taken as the constraint in the joints trajectory planning in the dissertation. For a prescribed location of the end-effector, the robot permits an infinite number of inverse solutions, which consequently yields infinite kinds of stiffness performance. Therefore, a differential evolution (DE) algorithm in which the positions of redundant joints in the kinematics are taken as input variables was employed to search for the best stiffness performance of the robot. Numerical results of the generated joint trajectories are given for a kinematic redundant serial-parallel robot machine, IWR (Intersector Welding/Cutting Robot), when a particular trajectory of its end-effector has been prescribed. The numerical results show that the joint trajectories generated based on the stiffness optimization are feasible for realization in the control system since they are acceptably smooth. The results imply that the stiffness performance of the robot machine deviates smoothly with respect to the kinematic configuration in the adjacent domain of its best stiffness performance. To suppress the vibration of the robot machine due to varying cutting force during the machining process, this dissertation proposed a feedforward control strategy, which is constructed based on the derived inverse dynamics model of target system. The effectiveness of applying such a feedforward control in the vibration suppression has been validated in a parallel manipulator in the software environment. The experimental study of such a feedforward control has also been included in the dissertation. The difficulties of modelling the actual system due to the unknown components in its dynamics is noticed. As a solution, a back propagation (BP) neural network is proposed for identification of the unknown components of the dynamics model of the target system. To train such a BP neural network, a modified Levenberg-Marquardt algorithm that can utilize an experimental input-output data set of the entire dynamic system is introduced in the dissertation. Validation of the BP neural network and the modified Levenberg- Marquardt algorithm is done, respectively, by a sinusoidal output approximation, a second order system parameters estimation, and a friction model estimation of a parallel manipulator, which represent three different application aspects of this method.

Simulation of the Interaction Mean Free Path between Neutrons and TRISO Particles

The interaction mean free path between neutrons and TRISO particles is simulated using scripts written in MATLAB to solve the increasing error present with an increase in the packing factor in the reactor physics code Serpent. Their movement is tracked both in an unbounded and in a bounded space. Their track is calculated, depending on the program, linearly directly using the position vectors of the neutrons and the surface equations of all the fuel particles; by dividing the space in multiple subspaces, each of which contain a fraction of the total number of particles, and choosing the particles from those subspaces through which the neutron passes through; or by choosing the particles that lie within an infinite cylinder formed on the movement axis of the neutron. The estimate from the current analytical model, based on an exponential distribution, for the mean free path, utilized by Serpent, is used as a reference result. The results from the implicit model in Serpent imply a too long mean free path with high packing factors. The received results support this observation by producing, with a packing factor of 17 %, approximately 2.46 % shorter mean free path compared to the reference model. This is supported by the packing factor experienced by the neutron, the simulation of which resulted in a 17.29 % packing factor. It was also observed that the neutrons leaving from the surfaces of the fuel particles, in contrast to those starting inside the moderator, do not follow the exponential distribution. The current model, as it is, is thus not valid in the determination of the free path lengths of the neutrons.

Advanced analysis and design methods for preparative chromatographic separation processes

Preparative liquid chromatography is one of the most selective separation techniques in the fine chemical, pharmaceutical, and food industries. Several process concepts have been developed and applied for improving the performance of classical batch chromatography. The most powerful approaches include various single-column recycling schemes, counter-current and cross-current multi-column setups, and hybrid processes where chromatography is coupled with other unit operations such as crystallization, chemical reactor, and/or solvent removal unit. To fully utilize the potential of stand-alone and integrated chromatographic processes, efficient methods for selecting the best process alternative as well as optimal operating conditions are needed. In this thesis, a unified method is developed for analysis and design of the following singlecolumn fixed bed processes and corresponding cross-current schemes: (1) batch chromatography, (2) batch chromatography with an integrated solvent removal unit, (3) mixed-recycle steady state recycling chromatography (SSR), and (4) mixed-recycle steady state recycling chromatography with solvent removal from fresh feed, recycle fraction, or column feed (SSR–SR). The method is based on the equilibrium theory of chromatography with an assumption of negligible mass transfer resistance and axial dispersion. The design criteria are given in general, dimensionless form that is formally analogous to that applied widely in the so called triangle theory of counter-current multi-column chromatography. Analytical design equations are derived for binary systems that follow competitive Langmuir adsorption isotherm model. For this purpose, the existing analytic solution of the ideal model of chromatography for binary Langmuir mixtures is completed by deriving missing explicit equations for the height and location of the pure first component shock in the case of a small feed pulse. It is thus shown that the entire chromatographic cycle at the column outlet can be expressed in closed-form. The developed design method allows predicting the feasible range of operating parameters that lead to desired product purities. It can be applied for the calculation of first estimates of optimal operating conditions, the analysis of process robustness, and the early-stage evaluation of different process alternatives. The design method is utilized to analyse the possibility to enhance the performance of conventional SSR chromatography by integrating it with a solvent removal unit. It is shown that the amount of fresh feed processed during a chromatographic cycle and thus the productivity of SSR process can be improved by removing solvent. The maximum solvent removal capacity depends on the location of the solvent removal unit and the physical solvent removal constraints, such as solubility, viscosity, and/or osmotic pressure limits. Usually, the most flexible option is to remove solvent from the column feed. Applicability of the equilibrium design for real, non-ideal separation problems is evaluated by means of numerical simulations. Due to assumption of infinite column efficiency, the developed design method is most applicable for high performance systems where thermodynamic effects are predominant, while significant deviations are observed under highly non-ideal conditions. The findings based on the equilibrium theory are applied to develop a shortcut approach for the design of chromatographic separation processes under strongly non-ideal conditions with significant dispersive effects. The method is based on a simple procedure applied to a single conventional chromatogram. Applicability of the approach for the design of batch and counter-current simulated moving bed processes is evaluated with case studies. It is shown that the shortcut approach works the better the higher the column efficiency and the lower the purity constraints are.

Livets källa kärleken : hälsans urkraft

This basic research focuses on the ethos of health and the human being's becoming in health. The theoretical perspective consists of the caring tradition within caring science developed at Åbo Akademy University. The aim of the present doctoral thesis is to uncover a new understanding as well as to deepen and attain a more nuanced understanding of the ethos of health, the essence of health, by penetrating to the core of what gives the human being the strength for experiencing a becoming in health. The research questions are as follows: l) What is the human being's source of strength? and 2) What reveals the source of strength so that the human being can perceive it and dedicate its strength in order to experience a becoming in health? The primary methodology used in the dissertation is hermeneutical. The material consists of the work Kärlekens gerningar by Kierkegaard, texts from focused interviews with respondents who have lived through severe personal suffering, as well as the book Det bländande mörkret by Wikström. These texts are interpreted through hermeneutical reading. The new horizon of understanding that emerges is reflected towards Eriksson's caritative theory, towards prior research within the tradition of caring science at Åbo Akademy University and towards previous national and international studies within this field. The new understanding shows that the human being's source of strength is love, the essence and origin of life. The substance of health is love, which, through the trinity of faith, hope and love, also makes possible the existence of the source of strength. Love has a deeper dignity than faith and hope, is connected with eternity and is the uniting link between temporality and eternity. The human being's inner longing entails an ontological attraction towards the source of strength. This source of strength is hidden, which provides and maintains its force, like a mystery connected with the darkness of suffering that hides the secret representing the source of strength, life's mystery, bu t w hi ch is revealed in both the darkness of suffering and in the light of joy. The dedication of strength requires freedom, willingness and courage to see the light, despite awareness of shame and guilt. Creative acts liberate the human being for the dedication of strength, which is preceded by a holy presence where, in solitude, the human being makes sacrifices for the sake of his or her human smallness and weakness, and allows himself or herself to be enclosed by the darkness of suffering to discover the light from the source. This entails being enraptured in a quiet "doing" in order to experience the beauty that bears witness to the holy which creates unity. The source of strength is revealed through beauty. The ethos of the human being and the ethos of health have the same fundamental substance, whilst the ethos of life possesses the deepest dimension and concerns the mysterious and infinite eternity. The ethos of life, eternity, which is a wellspring of strength, is not in itself strength-giving unless it is allied with love. Health can be understood in the light of life, of which death is an inevitable part. Life itself constitutes and creates the source which, through its alliance with eternity' s primordial wellspring of strength, generates strength from which the human being's source of strength, love, receives its eternal fervour. The human being is fundamentally interconnected with an abstract other, the first love, a universal wellspring of strength. Through Communion with this abstract other a dedication of the strength to experience a becoming in health becomes possible. Love for one's neighbour is the fundamental substance in the movement of becoming in health. Becoming in health presupposes a simultaneous movement in which the human being practices the human calling through ethos. As one loves one's neighbour through actions the still forces of eternity are in motion. When life emerges in the foreground and becomes the home of the human being, a dedication of the power of love is possible. Life itself determines the human being's becoming in health. A humble fundamental attitude towards life constitutes the basis for a continuous dedication of vitality from this source.