3D Surface Modeling From Point Clouds

The goal of this thesis is to implement software for creating 3D models from point clouds. Point clouds are acquired with stereo cameras, monocular systems or laser scanners. The created 3D models are triangular models or NURBS (Non-Uniform Rational B-Splines) models. Triangular models are constructed from selected areas from the point clouds and resulted triangular models are translated into a set of quads. The quads are further translated into an estimated grid structure and used for NURBS surface approximation. Finally, we have a set of NURBS surfaces which represent the whole model. The problem wasn’t so easy to solve. The selected triangular surface reconstruction algorithm did not deal well with noise in point clouds. To handle this problem, a clustering method is introduced for simplificating the model and removing noise. As we had better results with the smaller point clouds produced by clustering, we used points in clusters to better estimate the grids for NURBS models. The overall results were good when the point cloud did not have much noise. The point clouds with small amount of error had good results as the triangular model was solid. NURBS surface reconstruction performed well on solid models.

Determinação da massa molar por crioscopia: terc-butanol, um solvente extremamente adequado

We intend to divulge an easy experiment that permits the determination of molar masses of various compounds by cryoscopy. The major advantage of this is the use of the tert-butyl alcohol as a solvent, which requires simple apparatus and easy procedures. The melting point of this alcohol is around 25 ºC, which makes it easy to freeze and then melt the solutions. This solvent has a high cryoscopic constant and is miscible with both polar and non-polar compounds. The molar masses of acetone, water, chloroform, dichloro-methane, ethanol, hexane, carbon tetrachloride and toluene were determined. The results were good except for water. Even though there are reliable techniques of molar mass determination nowadays, this method is still frequently taught in undergraduate courses.

Lukion opettajien ääni - Aineenopettajien käsityksiä muutoksista ja visioista lukiossa

Tulevaisuusorientaatio on tullut entistä tärkeämmäksi myös koulumaailmassa johtuen yhteiskunnassa nopeasti eteen tulevista muutoksista. On myös esitetty epäilyjä, että tulevaisuuteen reagoimisessa heikoin tilanne olisikin juuri kuntatason päätöksenteossa. Ymmärrys ja tieto opettajan työstä nimenomaan opettajan omasta perspektiivistä tarkasteltuna mahdollistavat lähtökohdan ja edellytykset todelliselle koulun uudistamiselle. Peruskysymys, johon tässä tutkimuksessa etsittiin vastausta oli: Millaisia ovat lukion aineenopettajien käsitykset lukion muutosprosesseista ja miten he visioivat oman lukionsa ja yleensä lukioiden tulevaisuutta? Aineiston keruu osui ajankohtaan, joka oli hyvin otollinen tulevaisuuden tarkasteluun, sillä uusi opetussuunnitelma otettiin käyttöön kaikissa Suomen lukioissa viimeistään lukuvuonna 2005-2006. Tutkimuksessa oli mukana kaksi hyvin erilaista lukiota Länsi-Suomen läänistä eli pieni maaseudun lukio ja hyvin suuri kaupunkilukio. Tutkimusaineiston keruu eteni kaksivaiheisesti: informoitu kysely ja teemahaastattelu. Tutkimusjoukon suuruus oli yhteensä 20, joista puolet oli miehiä ja puolet naisia. Aineenopettajien käsityksiä muutoksista ja visioista tutkittiin fenomenografisen tutkimusotteen avulla. Fenomenografiassa kiinnostuksen kohteena ovat ihmisten erilaiset käsitykset todellisuudesta ja näin saatava ymmärrys tavoista, joilla ihmiset kokevat tilanteita ja maailmaa. Organisaation muutosprosesseja voidaan kutsua myös oppimiseksi. Tutkimuksen oppivan organisaation näkökulmat perustuivat juuri yhteistyössä tapahtuvaan yhteisen toiminnan kehittämiseen. Aineenopettajien käsityksiä työyhteisöstään tarkasteltiin seuraavista oppivan organisaatiomallin näkökulmista: vuorovaikutus, päätöksenteko sekä rehtorin ja aineenopettajan rooli ja asema työyhteisössä. Aineenopettajien keskeisimmät käsitykset muutoksista lukiossa viime vuosina kohdistuivat aineenopettajan ammattirooliin ja lukio-opiskelijaan sekä opiskelijalta vaadittaviin lukio-opintoihin. Muutokset ammattiroolissa korostavat tutkimustulosten perusteella aineenopettajilta vaadittavia muitakin kuin opetettavien aineiden hallintataitoja. Suoranaista ammattitaidon puutetta opettajat kokivat varsinkin ryhmänohjaustehtävien yhteydessä, osittain myös uusien oppimisympäristöjen, esimerkiksi verkkopedagogisten taitojen, yhteydessä. Opettajien lisäkoulutuksen tarve koetaan konkreettisena, mutta sekä koulutusten sisältöihin, järjestelyihin ja ajankohtiin että koulun sijais- ym. järjestelyihin kaivattaisiin parannuksia. Verrattuna aikaisempiin tutkimuksiin näyttäisi siltä, että luokaton lukio on saanut opettajat enenevässä määrin huolestumaan opiskelijoiden syrjäytymisriskistä ja hyvinvoinnista. Opiskelijoiden syrjäytymisriskin kasvu lukio-opintojen aikana nouseekin yhdeksi lukion pessimistiseksi skenaarioksi. Muista pessimistisistä skenaarioista lukiolle, jotka saattoi johtaa tutkimustuloksista, voidaan mainita työyhteisön demokratiavajeen syveneminen sekä opetussuunnitelmasisältöjen ja ylioppilastutkintovaatimusten välisen kuilun syveneminen. Aineenopettajien käsitykset oman lukionsa visioista olivat sisällöiltään pääosin välineellisiä ja ne kohdentuivat kaikki opiskelijoihin. Esimerkiksi työyhteisöllisiä kehittämisajatuksia ei visioissa ilmennyt. Myöskään visioinnin dynaamisuus ei aineistossa korostunut. Aineenopettajien käsitykset visioiden arvopohjasta heijastivat perinteistä suomalaista arvomaailmaa eli itsekuria, velvollisuudentuntoa, kuuliaisuutta esivaltaa kohtaan ja perinteisten arvojen kunnioittamista. Sen sijaan antiikista perityviä Sokrateen edustamia keskustelua ja auktoriteettien kyseenalaistamista ei arvoissa ilmennyt, eikä myöskään uusliberalistista individualismia. Käsitykset visioiden synnystä näyttävät parhaiten selittävän opettajan muita käsityksiä liittyen visioon, visiointiin ja työyhteisöllisiin vaikutusmahdollisuuksiin sekä opettajan tulevaisuusorientoitumiseen.. Käsitykset vision syntytaustasta voidaan jakaa seuraaviin pää- ja alakategorioihin: 1. auktoriteettikeskeinen visiointi: johdon linjaus tai valtakunnallinen linjaus, 2. yhteisökeskeinen visiointi: yhteisöllinen linjaus tai toiminnallinen linjaus ja 3. yksilökeskeinen visiointi. Pessimistisimmiksi eli vähiten tulevaisuusorientoituneiksi opettajiksi työyhteisössä osoittautuivat ne opettajat, jotka pitivät oman lukionsa visiota koulun johdon sanelemana. Monet teoriat oppivasta organisaatiosta korostavat johtajuuden merkitystä työyhteisöä kehitettäessä. Johtajuuden merkitys nousi tämänkin tutkimuksen aineistosta keskeisesti esiin. Pyrkimystä kohti oppivaa organisaatiota opettajien puheista löytyy paljonkin, esimerkkeinä viittaukset johtajuuden ja vuorovaikutustapojen kehittämistarpeisiin. Sen sijaan opettajien puheet omista työyhteisöllisistä kehittymistarpeistaan, ns. alaistaidot, jäivät vähäisiksi. Tutkimustuloksista on luotu sovellusmalli kouluyhteisöjen visioinnin ja muun kehittämistyön tueksi.

Essays on pricing of risk and international linkage of Russian stock market

Last two decades have seen a rapid change in the global economic and financial situation; the economic conditions in many small and large underdeveloped countries started to improve and they became recognized as emerging markets. This led to growth in the amounts of global investments in these countries, partly spurred by expectations of higher returns, favorable risk-return opportunities, and better diversification alternatives to global investors. This process, however, has not been without problems and it has emphasized the need for more information on these markets. In particular, the liberalization of financial markets around the world, globalization of trade and companies, recent formation of economic and regional blocks, and the rapid development of underdeveloped countries during the last two decades have brought a major challenge to the financial world and researchers alike. This doctoral dissertation studies one of the largest emerging markets, namely Russia. The motivation why the Russian equity market is worth investigating includes, among other factors, its sheer size, rapid and robust economic growth since the turn of the millennium, future prospect for international investors, and a number of important major financial reforms implemented since the early 1990s. Another interesting feature of the Russian economy, which gives motivation to study Russian market, is Russia’s 1998 financial crisis, considered as one of the worst crisis in recent times, affecting both developed and developing economies. Therefore, special attention has been paid to Russia’s 1998 financial crisis throughout this dissertation. This thesis covers the period from the birth of the modern Russian financial markets to the present day, Special attention is given to the international linkage and the 1998 financial crisis. This study first identifies the risks associated with Russian market and then deals with their pricing issues. Finally some insights about portfolio construction within Russian market are presented. The first research paper of this dissertation considers the linkage of the Russian equity market to the world equity market by examining the international transmission of the Russia’s 1998 financial crisis utilizing the GARCH-BEKK model proposed by Engle and Kroner. Empirical results shows evidence of direct linkage between the Russian equity market and the world market both in regards of returns and volatility. However, the weakness of the linkage suggests that the Russian equity market was only partially integrated into the world market, even though the contagion can be clearly seen during the time of the crisis period. The second and the third paper, co-authored with Mika Vaihekoski, investigate whether global, local and currency risks are priced in the Russian stock market from a US investors’ point of view. Furthermore, the dynamics of these sources of risk are studied, i.e., whether the prices of the global and local risk factors are constant or time-varying over time. We utilize the multivariate GARCH-M framework of De Santis and Gérard (1998). Similar to them we find price of global market risk to be time-varying. Currency risk also found to be priced and highly time varying in the Russian market. Moreover, our results suggest that the Russian market is partially segmented and local risk is also priced in the market. The model also implies that the biggest impact on the US market risk premium is coming from the world risk component whereas the Russian risk premium is on average caused mostly by the local and currency components. The purpose of the fourth paper is to look at the relationship between the stock and the bond market of Russia. The objective is to examine whether the correlations between two classes of assets are time varying by using multivariate conditional volatility models. The Constant Conditional Correlation model by Bollerslev (1990), the Dynamic Conditional Correlation model by Engle (2002), and an asymmetric version of the Dynamic Conditional Correlation model by Cappiello et al. (2006) are used in the analysis. The empirical results do not support the assumption of constant conditional correlation and there was clear evidence of time varying correlations between the Russian stocks and bond market and both asset markets exhibit positive asymmetries. The implications of the results in this dissertation are useful for both companies and international investors who are interested in investing in Russia. Our results give useful insights to those involved in minimising or managing financial risk exposures, such as, portfolio managers, international investors, risk analysts and financial researchers. When portfolio managers aim to optimize the risk-return relationship, the results indicate that at least in the case of Russia, one should account for the local market as well as currency risk when calculating the key inputs for the optimization. In addition, the pricing of exchange rate risk implies that exchange rate exposure is partly non-diversifiable and investors are compensated for bearing the risk. Likewise, international transmission of stock market volatility can profoundly influence corporate capital budgeting decisions, investors’ investment decisions, and other business cycle variables. Finally, the weak integration of the Russian market and low correlations between Russian stock and bond market offers good opportunities to the international investors to diversify their portfolios.

Merchandising Strategies and Retail Performance for Seasonal Fashion Products

This study presents mathematical methods for evaluation of retail performance with special regard to product sourcing strategies. Forecast accuracy, process lead time, offshore / local sourcing mix and up front / replenishment buying mix are defined as critical success factors in connection with sourcing seasonal products with a fashion content. As success measures, this research focuses on service level, lost sales, product substitute percentage, gross margin, gross margin return on inventory and mark down rate. The accuracy of demand forecast is found to be a fundamental success factor. Forecast accuracy depends on lead time. Lead times are traditionally long and buying decisions are made seven to eight months prior to the start of the selling season. Forecast errors cause stockouts and lost sales. Some of the products bought for the selling season will not be sold and have to be marked down and sold at clearance, causing loss of gross margin. Gross margin percentage is not the best tool for evaluating sourcing decisions and in the context of this study gross margin return on inventory, which combines profitability and assets management, is used. The findings of this research suggest that there are more profitable ways of sourcing products than buying them from low cost offshore sources. Mixing up front and inseason replenishment deliveries, especially when point of sale information is used for improving forecast accuracy, results in better retail performance. Quick Response and Vendor Managed Inventory strategies yield better results than traditional up front buying from offshore even if local purchase prices are higher. Increasing the number of selling seasons, slight over buying for the season in order to

Modelling nitrogen and phosphorus loads in a Mediterranean river catchment (La Tordera, NE Spain)

Human activities have resulted in increased nutrient levels in many rivers all over Europe. Sustainable management of river basins demands an assessment of the causes and consequences of human alteration of nutrient flows, together with an evaluation of management options. In the context of an integrated and interdisciplinary environmental assessment (IEA) of nutrient flows, we present and discuss the application of the nutrient emission model MONERIS (MOdelling Nutrient Emissions into River Systems) to the Catalan river basin, La Tordera (north-east Spain), for the period 1996–2002. After a successful calibration and verification process (Nash-Sutcliffe efficiencies E=0.85 for phosphorus and E=0.86 for nitrogen), the application of the model MONERIS proved to be useful in estimating nutrient loads. Crucial for model calibration, in-stream retention was estimated to be about 50 % of nutrient emissions on an annual basis. Through this process, we identified the importance of point sources for phosphorus emissions (about 94% for 1996–2002), and diffuse sources, especially inputs via groundwater, for nitrogen emissions (about 31% for 1996–2002). Despite hurdles related to model structure, observed loads, and input data encountered during the modelling process, MONERIS provided a good representation of the major interannual and spatial patterns in nutrient emissions. An analysis of the model uncertainty and sensitivity to input data indicates that the model MONERIS, even in data-starved Mediterranean catchments, may be profitably used by water managers for evaluating quantitative nutrient emission scenarios for the purpose of managing river basins. As an example of scenario modelling, an analysis of the changes in nutrient emissions through two different future scenarios allowed the identification of a set of relevant measures to reduce nutrient loads.

Extending the roughness of the data via transitive closures of similarity indexes

One main assumption in the theory of rough sets applied to information tables is that the elements that exhibit the same information are indiscernible (similar) and form blocks that can be understood as elementary granules of knowledge about the universe. We propose a variant of this concept defining a measure of similarity between the elements of the universe in order to consider that two objects can be indiscernible even though they do not share all the attribute values because the knowledge is partial or uncertain. The set of similarities define a matrix of a fuzzy relation satisfying reflexivity and symmetry but transitivity thus a partition of the universe is not attained. This problem can be solved calculating its transitive closure what ensure a partition for each level belonging to the unit interval [0,1]. This procedure allows generalizing the theory of rough sets depending on the minimum level of similarity accepted. This new point of view increases the rough character of the data because increases the set of indiscernible objects. Finally, we apply our results to a not real application to be capable to remark the differences and the improvements between this methodology and the classical one

Small scale energy production in Helsinki Metropolitan area in emission trading point of view

Emission trading with greenhouse gases and green certificates are part if the climate policy the main target of which is reduce greenhouse gas emissions. The carbon dioxide and fine particle emissions of energy production in Helsinki Metropolitan area are calculated in this study. The analysis is made mainly by district heating point of view and the changes of the district heating network are assessed. Carbon dioxide emissions would be a bit higher, if the district heating network is expanded, but then the fine particle emissions would be much lower. Carbon dioxide emissions are roughly 10 % higher, if the district heating network is expanded at same rate as it has in past five years in the year 2030. The expansion of district heating network would decrease the fine particle emissions about 40 %. The cost of the expansion is allocated to be reduction cost of the fine particle emissions, which is considerably higher than the traditional reduction methods costs. The possible new nuclear plant would reduce the emissions considerably and the costs of the nuclear plant would be relatively low comparing the other energy production methods.

Point sampling with uniformly distributed lines

In this paper we address the problem of extracting representative point samples from polygonal models. The goal of such a sampling algorithm is to find points that are evenly distributed. We propose star-discrepancy as a measure for sampling quality and propose new sampling methods based on global line distributions. We investigate several line generation algorithms including an efficient hardware-based sampling method. Our method contributes to the area of point-based graphics by extracting points that are more evenly distributed than by sampling with current algorithms

Commodity Price Driven Risk Management from Viewpoint of High Grade Steel Alloys

The study of price risk management concerning high grade steel alloys and their components was conducted. This study was focused in metal commodities, of which nickel, chrome and molybdenum were in a central role. Also possible hedging instruments and strategies for referred metals were studied. In the literature part main themes are price formation of Ni, Cr and Mo, the functioning of metal exchanges and main hedging instruments for metal commodities. This section also covers how micro and macro variables may affect metal prices from the viewpoint of short as well as longer time period. The experimental part consists of three sections. In the first part, multiple regression model with seven explanatory variables was constructed to describe price behavior of nickel. Results were compared after this with information created with comparable simple regression model. Additionally, long time mean price reversion of nickel was studied. In the second part, theoretical price of CF8M alloy was studied by using nickel, ferro-chrome and ferro-molybdenum as explanatory variables. In the last section, cross hedging possibilities for illiquid FeCr -metal was studied with five LME futures. Also this section covers new information concerning possible forthcoming molybdenum future contracts as well. The results of this study confirm, that linear regression models which are based on the assumption of market rationality, are not able to reliably describe price development of metals at issue. Models fulfilling assumptions for linear regression may though include useful information of statistical significant variables which have effect on metal prices. According to the experimental part, short futures were found to incorporate the most accurate information concerning the price movements in the future. However, not even 3M futures were able to predict turning point in the market before the faced slump. Cross hedging seemed to be very doubtful risk management strategy for illiquid metals, because correlations coefficients were found to be very sensitive for the chosen time span.

Cost estimation framework for modular product

Cost estimation is an important, but challenging process when designing a new product or a feature of it, verifying the product prices given by suppliers or planning a cost saving actions of existing products. It is even more challenging when the product is highly modular, not a bulk product. In general, cost estimation techniques can be divided into two main groups - qualitative and quantitative techniques - which can further be classified into more detailed methods. Generally, qualitative techniques are preferable when comparing alternatives and quantitative techniques when cost relationships can be found. The main objective of this thesis was to develop a method on how to estimate costs of internally manufactured and commercial elevator landing doors. Because of the challenging product structure, the proposed cost estimation framework is developed under three different levels based on past cost information available. The framework consists of features from both qualitative and quantitative cost estimation techniques. The starting point for the whole cost estimation process is an unambiguous, hierarchical product structure so that the product can be classified into controllable parts and is then easier to handle. Those controllable parts can then be compared to existing past cost knowledge of similar parts and create as accurate cost estimates as possible by that way.

Performance Improvement of Centrifugal Compressor Stage with Pinched Geometry or Vaned Diffuser

Centrifugal compressors are widely used for example in refrigeration processes, the oil and gas industry, superchargers, and waste water treatment. In this work, five different vaneless diffusers and six different vaned diffusers are investigated numerically. The vaneless diffusers vary only by their diffuser width, so that four of the geometries have pinch implemented to them. Pinch means a decrease in the diffuser width. Four of the vaned diffusers have the same vane turning angle and a different number of vanes, and two have different vane turning angles. The flow solver used to solve the flow fields is Finflo, which is a Navier-Stokes solver. All the cases are modeled with the Chien's k – έ- turbulence model, and selected cases are modeled also with the k – ώ-SST turbulence model. All five vaneless diffusers and three vaned diffusers are investigated also experimentally. For each construction, the compressor operating map is measured according to relevant standards. In addition to this, the flow fields before and after the diffuser are measured with static and total pressure, flow angle and total temperature measurements. When comparing the computational results to the measured results, it is evident that the k – ώ-SST turbulence model predicts the flow fields better. The simulation results indicate that it is possible to improve the efficiency with the pinch, and according to the numerical results, the two best geometries are the ones with most pinch at the shroud. These geometries have approximately 4 percentage points higher efficiency than the unpinched vaneless diffusers. The hub pinch does not seem to have any major benefits. In general, the pinches make the flow fields before and after the diffuser more uniform. The pinch also seems to improve the impeller efficiency. This is down to two reasons. The major reason is that the pinch decreases the size of slow flow and possible backflow region located near the shroud after the impeller. Secondly, the pinches decrease the flow velocity in the tip clearance, leading to a smaller tip leakage flow and therefore slightly better impeller efficiency. Also some of the vaned diffusers improve the efficiency, the increment being 1...3 percentage points, when compared to the vaneless unpinched geometry. The measurement results confirm that the pinch is beneficial to the performance of the compressor. The flow fields are more uniform with the pinched cases, and the slow flow regions are smaller. The peak efficiency is approximately 2 percentage points and the design point efficiency approximately 4 percentage points higher with the pinched geometries than with the un- pinched geometry. According to the measurements, the two best geometries are the ones with the most pinch at the shroud, the case with the pinch only at the shroud being slightly better of the two. The vaned diffusers also have better efficiency than the vaneless unpinched geometries. However, the pinched cases have even better efficiencies. The vaned diffusers narrow the operating range considerably, whilst the pinch has no significant effect on the operating range.

Splat-based surface reconstruction from defect-laden point sets

We introduce a method for surface reconstruction from point sets that is able to cope with noise and outliers. First, a splat-based representation is computed from the point set. A robust local 3D RANSAC-based procedure is used to filter the point set for outliers, then a local jet surface - a low-degree surface approximation - is fitted to the inliers. Second, we extract the reconstructed surface in the form of a surface triangle mesh through Delaunay refinement. The Delaunay refinement meshing approach requires computing intersections between line segment queries and the surface to be meshed. In the present case, intersection queries are solved from the set of splats through a 1D RANSAC procedure

Supporting older people’s independent living at home through social and health care collaboration

Tässä tutkimuksessa tarkasteltiin ikäihmisten kotona asumista sosiaali- ja terveydenhuollon yhteistyön näkökulmasta. Tutkimuksen tarkoituksena oli lisätä ymmärrystä iäkkäiden kotihoidon asiakkaiden voimavaroista arjesta selviytymisen näkökulmasta, ja tutkia miten asiakkaiden hoito sosiaali- ja terveydenhuollon yhteistyönä toteutuu. Tutkimus oli poikkileikkaustutkimus, jossa sovellettiin kuvailevaa ja vertailevaa tutkimusasetelmaa. Tutkimusaineisto kerättiin yhden länsisuomalaisen kunnan kotihoidon asiakkailta (≥65 v.) ja heitä hoitavilta ammattihenkilöiltä. Kotihoidon 21 iäkästä asiakasta kuvasivat omia voimavarojaan arjesta selviytymisen näkökulmasta sekä kokemuksiaan hoidon toteutumisesta ammattihenkilöiden yhteistyönä. Aineisto kerättiin avoimella haastattelulla ja analysoitiin sisällön analyysillä. Lisäksi 25 kotihoidon ammattihenkilöä: 13 kotipalvelun työntekijää, 11 kotisairaanhoitajaa ja lääkäri kuvasivat kokemuksiaan iäkkään asiakkaan hoidon toteutumisesta ammattihenkilöiden yhteistyönä. Aineisto kerättiin fokusryhmähaastattelulla ja analysoitiin sisällön analyysillä. Näiden tulosten sekä aikaisemman kirjallisuuden perusteella laadittiin strukturoitu kyselylomake, jolla analysoitiin ja vertailtiin asiakkaiden ja ammattihenkilöiden näkemyksiä siitä, miten asiakkaiden hoito sosiaali- ja terveydenhuollon yhteistyönä toteutui. Esitestausten jälkeen kyselylomake lähetettiin 200 kotihoidon asiakkaalle ja 570 heitä hoitavalle kotihoidon työntekijälle: 485 kotipalvelun työntekijälle, 81 kotisairaanhoitajalle ja 4 lääkärille. Kyselyyn vastasi 120 asiakasta (60 %) ja 370 ammattihenkilöä (65 %). Ryhmien välisten erojen tarkastelussa käytettiin ristiintaulukointia, Pearsonin khin neliötestiä ja Fisherin tarkan todennäköisyyden testiä. Iäkkäiden asiakkaiden kuvauksissa voimavarat muodostuivat elämänhallinnan tunteesta ja toimintatahdon säilymisestä. Asiakkaat ammensivat arkeen voimaa harrastuksista ja sosiaalisesta verkostosta, mutta ulkopuolisten asettamat elämisen ehdot, terveydentilan heikkeneminen sekä yksinäisyys asettivat ikäihmisen ja hänen voimavaransa suurten haasteiden eteen. Tulokset osoittivat, että ammattihenkilöiden toiminta oli osittain ristiriidassa ikäihmisten omien odotusten kanssa, eikä se kaikilta osin tukenut asiakkaiden omia voimavaroja. Ammattihenkilöt tekivät hoitoon liittyviä päätöksiä ja toimintoja asiakkaiden puolesta, vaikka asiakkaille itselleen oli tärkeää elämänhallinnan tunne ja toimintatahdon säilyminen. Asiakkaiden voimavarojen tukemista moniammatillisena yhteistyönä vaikeuttivat ammattihenkilöiden vaikeus tunnistaa asiakkaiden omia voimavaroja sekä niitä uhkaavia tekijöitä, tiedon kulun ongelmat, tavoitteeton ja epäyhtenäinen tapa toimia sekä ammattihenkilöiden vastakkain asettuvat näkemyserot ja toimintatavat. Asiakkaiden ja ammattihenkilöiden näkemykset toteutetusta hoidosta erosivat toisistaan tilastollisesti merkitsevästi (p<0.05). Asiakkaat arvioivat sekä itsenäiseen toimintaan tukemisen että fyysisen, psyykkisen ja sosiaalisen tuen toteutuneen työntekijöitä huonommin. Yhteistyön kehittämishaasteita kotihoidossa ovat asiakkaan oman elämänsä asiantuntijuuden vahvistaminen, toimintakulttuurin muuttaminen asiakaslähtöiseksi tavoitteelliseksi toiminnaksi, ammattihenkilöiden roolien ja vastuun selkiyttäminen sekä tiedon kulun menetelmien kehittäminen. Tutkimus vahvistaa gerontologisen hoitotieteen tietoperustaa ja tuottaa uutta tietoa, jota voidaan soveltaa sosiaali- ja terveysalan koulutuksessa ja johtamisessa

Water circulations for effective bleaching of high-brightness mechanical pulps

The amount of water available is usually restricted, which leads to a situation where a complete understanding of the process, including water circulations and the influence of water components, is essential. The main aim of this thesis was to clarify the possibilities for the efficient use of residual peroxide by means of water circulation rearrangements. Rearranging water circulations and the reduction of water usage may cause new problems, such as metal induced peroxide decomposition that needs to be addressed. This thesis introduces theoretical methods of water circulations to combine two variables; effective utilization of residual peroxide and avoiding manganese in the alkaline peroxide bleaching stage. Results are mainly based on laboratory and mill site experiments concerning the utilization of residual peroxide. A simulation model (BALAS) was used to evaluate the manganese contents and residual peroxide doses. It was shown that with optimum recirculation of residual peroxide the brightness can be improved or chemical costs can be decreased. From the scientific perspective, it was also very important to discover that recycled peroxide was more effective pre-bleaching agent compared to fresh peroxide. This can be due to the organic acids i.e. per acetic acid in wash press filtrate that have been formed in alkaline bleaching stage. Even short retention time was adequate and the activation of residual peroxide using sodium hydroxide was not necessary. There are several possibilities for using residual peroxide in practice regarding bleaching. A typical modern mechanical pulping process line consist of defibering, screening, a disc filter, a bleach press, high consistency (HC) peroxide bleaching and a wash press. Furthermore there usually is not a particular medium consistency (MC) pre-bleaching stage that includes additional thickening equipment. The most advisable way to utilize residual peroxide in this kind of process is to recycle the wash press filtrate to the dilution of disc filter pulp (low MC pre-bleaching stage). An arrangement such as this would be beneficial in terms of the reduced convection of manganese to the alkaline bleaching stage. Manganese originates from wood material and will be removed to the water phase already in the early stages of the process. Recycling residual peroxide prior to the disc filter is not recommended because of low consistencies. Regarding water circulations, the novel point of view is that, it would be beneficial to divide water circulations into two sections and the critical location for the division is the disc filter. Both of these two sections have their own priority. Section one before the disc filter: manganese removal. Section two after the disc filter: brightening of pulp. This division can be carried out if the disc filter pulp is diluted only by wash press filtrate before the MC storage tower. The situation is even better if there is an additional press after the disc filter, which will improve the consistency of the pulp. This has a significant effect on the peroxide concentration in the MC pre-bleaching stage. In terms of manganese content, it is essential to avoid the use of disc filter filtrate in the bleach press and wash press showers. An additional cut-off press would also be beneficial for manganese removal. As a combination of higher initial brightness and lower manganese content, the typical brightness increase varies between approximately 0.5 and 1% ISO units after the alkaline peroxide bleaching stage. This improvement does not seem to be remarkable, but as it is generally known, the final brightness unit is the most expensive and difficult to achieve. The estimation of cost savings is not unambiguous. For example in GW/TMP mill case 0.6% ISO units higher final brightness gave 10% savings in the costs of bleaching chemicals. With an hypothetical 200 000 ton annual production, this means that the mill could save in the costs of bleaching chemicals more than 400 000 euros per year. In general, it can be said that there were no differences between the behavior of different types of processes (GW, PGW, TMP and BCTMP). The enhancement of recycling gave a similar response in all cases. However, we have to remember that the utilization of residual peroxide in older mills depends a great deal on the process equipment, the amount of water available and existing pipeline connections. In summary, it can be said that processes are individual and the same solutions cannot be applied to all cases.