3 resultados para Retreat

em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland


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In many industrial applications, such as the printing and coatings industry, wetting of porous materials by liquids includes not only imbibition and permeation into the bulk but also surface spreading and evaporation. By understanding these phenomena, valuable information can be obtained for improved process control, runnability and printability, in which liquid penetration and subsequent drying play important quality and economic roles. Knowledge of the position of the wetting front and the distribution/degree of pore filling within the structure is crucial in describing the transport phenomena involved. Although exemplifying paper as a porous medium in this work, the generalisation to dynamic liquid transfer onto a surface, including permeation and imbibition into porous media, is of importance to many industrial and naturally occurring environmental processes. This thesis explains the phenomena in the field of heatset web offset printing but the content and the analyses are applicable in many other printing methods and also other technologies where water/moisture monitoring is crucial in order to have a stable process and achieve high quality end products. The use of near-infrared technology to study the water and moisture response of porous pigmented structures is presented. The use of sensitive surface chemical and structural analysis, as well as the internal structure investigation of a porous structure, to inspect liquid wetting and distribution, complements the information obtained by spectroscopic techniques. Strong emphasis has been put on the scale of measurement, to filter irrelevant information and to understand the relationship between interactions involved. The near-infrared spectroscopic technique, presented here, samples directly the changes in signal absorbance and its variation in the process at multiple locations in a print production line. The in-line non-contact measurements are facilitated by using several diffuse reflectance probes, giving the absolute water/moisture content from a defined position in the dynamic process in real-time. The nearinfrared measurement data illustrate the changes in moisture content as the paper is passing through the printing nips and dryer, respectively, and the analysis of the mechanisms involved highlight the roles of the contacting surfaces and the relative liquid carrier properties of both non-image and printed image areas. The thesis includes laboratory studies on wetting of porous media in the form of coated paper and compressed pigment tablets by mono-, dual-, and multi-component liquids, and paper water/moisture content analysis in both offline and online conditions, thus also enabling direct sampling of temporal water/moisture profiles from multiple locations. One main focus in this thesis was to establish a measurement system which is able to monitor rapid changes in moisture content of paper. The study suggests that near-infrared diffuse reflectance spectroscopy can be used as a moisture sensitive system and to provide accurate online qualitative indicators, but, also, when accurately calibrated, can provide quantification of water/moisture levels, its distribution and dynamic liquid transfer. Due to the high sensitivity, samples can be measured with excellent reproducibility and good signal to noise ratio. Another focus of this thesis was on the evolution of the moisture content, i.e. changes in moisture content referred to (re)wetting, and liquid distribution during printing of coated paper. The study confirmed different wetting phases together with the factors affecting each phase both for a single droplet and a liquid film applied on a porous substrate. For a single droplet, initial capillary driven imbibition is followed by equilibrium pore filling and liquid retreat by evaporation. In the case of a liquid film applied on paper, the controlling factors defining the transportation were concluded to be the applied liquid volume in relation to surface roughness, capillarity and permeability of the coating giving the liquid uptake capacity. The printing trials confirmed moisture gradients in the printed sheet depending on process parameters such as speed, fountain solution dosage and drying conditions as well as the printed layout itself. Uneven moisture distribution in the printed sheet was identified to be one of the sources for waving appearance and the magnitude of waving was influenced by the drying conditions.

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Tässä kandidaatin työssä on tutkitti miten eri jännityskomponentit käyttäytyvät rivan kärjen läheisyydessä. Työssä tutkittiin kahta eri mallia, rivallista levyä ja rivallista levyä hitsauksesta johtuvalla kulmavetäymällä. Tutkimus suoritettiin FEA-analyysin avulla. Komponenttien käyttäytymistä tutkittiin sekä veto- että taivutuskuormituksella. Tuloksissa on verrattu miten kulmavetäymä vaikuttaa komponenttien syntyyn ja miten eri kuormituksilla saadut tulokset poikkeavat toisistaan.

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Mothers represent the natural caring. Natural caring is the object of caring science and of research interest because it establishes the central core of professional caring. In this study, we encounter patients who are mothers in need of care in a psychiatric context. Motherhood involves taking responsibility that extends beyond one's own life, because the child represents possibilities in a yet unknown future. Understanding and knowledge about the mothers' struggle in health and suffering are of crucial importance to enable clinical practice to make provisions for and adapt to the individual patient. The overall purpose of this dissertation is to illuminate how the innermost essence of caring emerges in health and suffering in patients who are mothers in psychiatric care. The purpose of the study in a clinical sense is to seek to understand and illuminate the patient's inner world in health and suffering in terms of contextual, existential, ontological and ethical dimensions. The dissertation is exploratory and descriptive in nature and encompasses induction, deduction and abduction as logics tools of reasoning. A theoretical model of natural caring and a universal theoretical model of the innermost essence of caring is developed as seen from the patient's world in a psychiatric context. The dissertation is anchored in human science's view of the human being and the world and in caring science's perspective. Caring science's view of the human being as a unity comprising body, soul and spirit is central in the study's concept of the patient. This multi-dimensional conception of the human being encompasses the dissertation's basic values and is decisive for choice of methodology. Hermeneutic epistemology guided the interpretation of the empirical data, the paradigmatic theses and assumptions. The dialectical movement in interpretation moves back and forth between empirical data, caring science theory and philosophical theory and reveals deeper insight into meaningful content in the clinical context. The interpretation process comprises four levels of abstraction: rational, contextual, existential and ontological. Hermeneutic philosophy guides the inductive and deductive approach to interpretation, as well as the movement between the clinical context and the caring science paradigm. In this encounter between the visible and invisible reality, the image of natural caring – motherliness emerged. The dissertation consists of four studies. The first study is a systematic review of nineteen research articles. The three other studies are hermeneutical interpretations based on text materials from open interviews. Fifteen participants were interviewed, all of whom are mothers of children between 0 and 18 years of age. All were outpatients in the psychiatric specialist health service. In the interpretation process, the mothers' struggle in health and suffering emerges as a struggle between the inner and outer world. Being a mother and patient in health and suffering in a psychiatric context means to struggle to be oneself, to create oneself, to live and realize one's good deeds as a mother and human being. To be oneself, to possess oneself as a mother is not only a question of tending, playing and learning in order to master a practical situation or to survive. It involves constituting a deep, inner desire to courageously create oneself so that the child is able to realize his or her potential in health and suffering. Motherliness manifests itself in caring as a call to ministering humanity and life. The voice of motherliness is understood as the voice of life—the eternal, inner call of love and freedom. The inner call craves fulfilment. Motherliness in natural caring does not retreat. Motherliness defines the Other as freedom and proceeds without regard for all other exterior requirements to realizing wellbeing. The inner essence of caring is attentive, aware and heeds the call of the heart. The innermost essence of caring is to be and to make oneself responsible for the Other. Responsibility cannot be relinquished; free choice consists in whether or not to follow the call. To renounce the inner call to responsibility is to deny oneself and one's dignity as a human being. The theoretical models provide clinical and systematic caring science with knowledge and understanding based on the natural caring spirit inherent in the human being. The study elucidates and strengthens the ontological basic assumptions about the human being as a unity of body, soul and spirit, the sanctity of the human being and the core of caring, ethos. The results of the dissertation will provide clinical practice with knowledge about the inner movements of the mothers' souls in relation to their responsibility as mothers and human beings. Being able to understand the basic conditions for responsibility is crucial for developing care that encompasses mother and child and the mutual relationship between them. This is basic knowledge for developing attitudes and actions that meet and provide for the needs of the patient as mother and as a whole, suffering human being.