866 resultados para modelling and simulation
Resumo:
In the last 30 years world population has increased 70% but per capita global fruit consumption is only 20% higher. Even though tropical and temperate fruit have similar contributions to the 50 kg/person/year of US consumption of fresh fruit, in the last 30 years this has been slightly greater for temperate fruit. Within fruit consumption, the largest expansion has been for organic fruit which increased more than 50% in the 2002-2006 period. The largest expansion of area planted in the 1996-2006 has been for kiwi (29%) and blueberries (20%), while apples (-24%) and sour cherries (-13%) have had the largest reductions. Nearly 50% of the total global volume of fruit is produced by 5 countries: China, USA, Brazil, Italy and Spain. The main producer (China) accounts for 23% of the total. While the main exporters are Spain, USA and Italy, the main importers are Germany, Russia and UK. Demands for the industry have evolved towards quality, food safety and traceability. The industry faces higher productions costs (labor, energy, agrichemicals). The retailers are moving towards consolidation while the customers are changing preferences (food for health). In this context there is greater pressure on growers, processors and retailers. Emerging issues are labor supply, climate change, water availability and sustainability. Recent developments in precision agriculture, molecular biology, phenomics, crop modelling and post harvest physiology should increase yields and quality, and reduce costs for temperate fruit production around the world.
Resumo:
Angiogenesis plays a key role in tumor growth and cancer progression. TIE-2-expressing monocytes (TEM) have been reported to critically account for tumor vascularization and growth in mouse tumor experimental models, but the molecular basis of their pro-angiogenic activity are largely unknown. Moreover, differences in the pro-angiogenic activity between blood circulating and tumor infiltrated TEM in human patients has not been established to date, hindering the identification of specific targets for therapeutic intervention. In this work, we investigated these differences and the phenotypic reversal of breast tumor pro-angiogenic TEM to a weak pro-angiogenic phenotype by combining Boolean modelling and experimental approaches. Firstly, we show that in breast cancer patients the pro-angiogenic activity of TEM increased drastically from blood to tumor, suggesting that the tumor microenvironment shapes the highly pro-angiogenic phenotype of TEM. Secondly, we predicted in silico all minimal perturbations transitioning the highly pro-angiogenic phenotype of tumor TEM to the weak pro-angiogenic phenotype of blood TEM and vice versa. In silico predicted perturbations were validated experimentally using patient TEM. In addition, gene expression profiling of TEM transitioned to a weak pro-angiogenic phenotype confirmed that TEM are plastic cells and can be reverted to immunological potent monocytes. Finally, the relapse-free survival analysis showed a statistically significant difference between patients with tumors with high and low expression values for genes encoding transitioning proteins detected in silico and validated on patient TEM. In conclusion, the inferred TEM regulatory network accurately captured experimental TEM behavior and highlighted crosstalk between specific angiogenic and inflammatory signaling pathways of outstanding importance to control their pro-angiogenic activity. Results showed the successful in vitro reversion of such an activity by perturbation of in silico predicted target genes in tumor derived TEM, and indicated that targeting tumor TEM plasticity may constitute a novel valid therapeutic strategy in breast cancer.
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Lymphomas arising from NK or γδ-T cells are very aggressive diseases and little is known regarding their pathogenesis. Here we report frequent activating mutations of STAT3 and STAT5B in NK/T-cell lymphomas (n=51), γδ-T-cell lymphomas (n=43) and their cell lines (n=9) through next generation and/or Sanger sequencing. STAT5B N642H is particularly frequent in all forms of γδ-T-cell lymphomas. STAT3 and STAT5B mutations are associated with increased phosphorylated protein and a growth advantage to transduced cell lines or normal NK cells. Growth-promoting activity of the mutants can be partially inhibited by a JAK1/2 inhibitor. Molecular modelling and surface plasmon resonance measurements of the N642H mutant indicate a marked increase in binding affinity of the phosphotyrosine-Y699 with the mutant histidine. This is associated with the prolonged persistence of the mutant phosphoSTAT5B and marked increase of binding to target sites. Our findings suggest that JAK-STAT pathway inhibition may represent a therapeutic strategy.
Resumo:
Tämä diplomityö on tehty Andritz Oy:lle Washers & Filters tuoteryhmään. Työ on osa 3D-suunnittelujärjestelmän käyttöönottoprojektia. Tavoitteena on arvioida uuden laitesuunnittelujärjestelmän vaikutuksia yrityksen tietojärjestelmiin ja toimintatapoihin sekä etsiä potentiaalisia tulevaisuuden kehityskohteita. Suunnittelutietoa hyödyntäviä sidosryhmien edustajia haastattelemalla selvitettiin järjestelmille ja ohjelmistoille asetettavia vaatimuksia. Ohjelmistoihin tutustumalla saatiin käsitys niiden nykytilasta ja kehityssuunnista. 3D-geometrian hyödyntämiseen perustuvilla järjestelmillä voidaan poistaa päällekäistä työtä sekä lyhentää läpimenoaikoja suunnittelussa ja valmistuksessa sijoittamalla työvaiheita rinnakkain. Suurimmat 3D-suunnittelun edut saavutetaan tuotekehitysvaiheessa, tuotemuutoksia tehtäessä sekä valmistusprosesseja suunniteltaessa. Ongelmallisimmat osa-alueet tietojärjestelmien kehittämisessä ovat ensi-sijaisesti tiedonsiirto ohjelmistojen välillä, työntekijöiden muutosvastarinta sekä laadukkaiden järjestelmien korkea hinta. Laajojen tietojärjestelmä-projektien läpivienti on hyvin haastavaa ja onnistuminen vaatii kaikkien sidosryhmien mukana olemista ja tarkkaa projektin koordinointia.
Resumo:
Diplomityössä tehtiin Balas- simulointimalli Stora Enso Publication Papers Oy Ltd Varkauden tehtaiden kuumahierrelaitoksesta, johon sovitettiin tehtaan lämpö-, kuitu- ja kiertovesivirtaukset sekä kiertovesissä olevien liuenneiden ja kolloidisten aineiden virtaukset. Kirjallisuusosassa perehdyttiin simulaattorimallin luontiin ja käyttötarkoituksiin. Siinä käsitellään Balas- simulaattorin ominaisuuksia ja laiteparametrointia. Tarkastellaan kuumahierreprosessin eri vaiheita, olosuhteita ja laitteiden toimintaa. Perehdytään prosessin energian kulutukseen ja talteenottoon sekä kiertovesien liuenneiden ja kolloidisten aineiden mittaussuureisiin ja vaikutuksiin prosessissa. Simulaattorimallin tekemiseen kuului tehtaan virtauskaavion ja simulaattorimallin tekeminen, mittauskoesuunnittelu, tehdasmittaukset, simulaattorin parametrointi, mittaus- ja simulaattoritulosten yhteensovittaminen sekä mallin kelpoistaminen. Tehtaan virtauskaavion piirtämisessä käytettiin apuna tehtaan prosessi- ja instrumentointikaavioita, joiden pohjalta mittauskoesuunnitelma ja simulaattorimalli tehtiin. Koesuunnitelman mittaussuureiksi valittiin virtaukset, sakeudet, lämpötilat sekä kiertovesien kiintoaineen-, kokonaisorgaanisen hiilen- ja liuenneen orgaanisen aineen pitoisuuksien määritykset. Mittauksilla saatiin tietoja prosessivirtausten taseista, joita käytettiin simulaattorimallin keskeisempien laiteparametriarvojen määrityksessä. Exceliä hyödynnettiin mittaus- ja simulaattoritulosten taulukoinnissa, laiteparametrien laskemisessa sekä arvojen syötössä ja vastaanotossa Excelin ja simulaattorin välillä. Sitä käytettiin myös graafisessa mittaus- ja simulaattoritulosten yhteensovittamisessa, jolla pystyttiin havainnollisesti näkemään eri syöttöparametrien muutoksien vaikutukset simulaattorin laskemissa virtaustuloksissa. Mallin antamien arvojen ja todellisten prosessimittausarvojen yhteensovittamisen ja mallista varmistumisen tuloksista voidaan todeta mallin korreloivan todellista prosessia melko hyvin.
Resumo:
1. Species distribution models (SDMs) have become a standard tool in ecology and applied conservation biology. Modelling rare and threatened species is particularly important for conservation purposes. However, modelling rare species is difficult because the combination of few occurrences and many predictor variables easily leads to model overfitting. A new strategy using ensembles of small models was recently developed in an attempt to overcome this limitation of rare species modelling and has been tested successfully for only a single species so far. Here, we aim to test the approach more comprehensively on a large number of species including a transferability assessment. 2. For each species numerous small (here bivariate) models were calibrated, evaluated and averaged to an ensemble weighted by AUC scores. These 'ensembles of small models' (ESMs) were compared to standard Species Distribution Models (SDMs) using three commonly used modelling techniques (GLM, GBM, Maxent) and their ensemble prediction. We tested 107 rare and under-sampled plant species of conservation concern in Switzerland. 3. We show that ESMs performed significantly better than standard SDMs. The rarer the species, the more pronounced the effects were. ESMs were also superior to standard SDMs and their ensemble when they were independently evaluated using a transferability assessment. 4. By averaging simple small models to an ensemble, ESMs avoid overfitting without losing explanatory power through reducing the number of predictor variables. They further improve the reliability of species distribution models, especially for rare species, and thus help to overcome limitations of modelling rare species.
Resumo:
As the development of integrated circuit technology continues to follow Moore’s law the complexity of circuits increases exponentially. Traditional hardware description languages such as VHDL and Verilog are no longer powerful enough to cope with this level of complexity and do not provide facilities for hardware/software codesign. Languages such as SystemC are intended to solve these problems by combining the powerful expression of high level programming languages and hardware oriented facilities of hardware description languages. To fully replace older languages in the desing flow of digital systems SystemC should also be synthesizable. The devices required by modern high speed networks often share the same tight constraints for e.g. size, power consumption and price with embedded systems but have also very demanding real time and quality of service requirements that are difficult to satisfy with general purpose processors. Dedicated hardware blocks of an application specific instruction set processor are one way to combine fast processing speed, energy efficiency, flexibility and relatively low time-to-market. Common features can be identified in the network processing domain making it possible to develop specialized but configurable processor architectures. One such architecture is the TACO which is based on transport triggered architecture. The architecture offers a high degree of parallelism and modularity and greatly simplified instruction decoding. For this M.Sc.(Tech) thesis, a simulation environment for the TACO architecture was developed with SystemC 2.2 using an old version written with SystemC 1.0 as a starting point. The environment enables rapid design space exploration by providing facilities for hw/sw codesign and simulation and an extendable library of automatically configured reusable hardware blocks. Other topics that are covered are the differences between SystemC 1.0 and 2.2 from the viewpoint of hardware modeling, and compilation of a SystemC model into synthesizable VHDL with Celoxica Agility SystemC Compiler. A simulation model for a processor for TCP/IP packet validation was designed and tested as a test case for the environment.
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Coastal birds are an integral part of coastal ecosystems, which nowadays are subject to severe environmental pressures. Effective measures for the management and conservation of seabirds and their habitats call for insight into their population processes and the factors affecting their distribution and abundance. Central to national and international management and conservation measures is the availability of accurate data and information on bird populations, as well as on environmental trends and on measures taken to solve environmental problems. In this thesis I address different aspects of the occurrence, abundance, population trends and breeding success of waterbirds breeding on the Finnish coast of the Baltic Sea, and discuss the implications of the results for seabird monitoring, management and conservation. In addition, I assess the position and prospects of coastal bird monitoring data, in the processing and dissemination of biodiversity data and information in accordance with the Convention on Biological Diversity (CBD) and other national and international commitments. I show that important factors for seabird habitat selection are island area and elevation, water depth, shore openness, and the composition of island cover habitats. Habitat preferences are species-specific, with certain similarities within species groups. The occurrence of the colonial Arctic Tern (Sterna paradisaea) is partly affected by different habitat characteristics than its abundance. Using long-term bird monitoring data, I show that eutrophication and winter severity have reduced the populations of several Finnish seabird species. A major demographic factor through which environmental changes influence bird populations is breeding success. Breeding success can function as a more rapid indicator of sublethal environmental impacts than population trends, particularly for long-lived and slowbreeding species, and should therefore be included in coastal bird monitoring schemes. Among my target species, local breeding success can be shown to affect the populations of the Mallard (Anas platyrhynchos), the Eider (Somateria mollissima) and the Goosander (Mergus merganser) after a time lag corresponding to their species-specific recruitment age. For some of the target species, the number of individuals in late summer can be used as an easier and more cost-effective indicator of breeding success than brood counts. My results highlight that the interpretation and application of habitat and population studies require solid background knowledge of the ecology of the target species. In addition, the special characteristics of coastal birds, their habitats, and coastal bird monitoring data have to be considered in the assessment of their distribution and population trends. According to the results, the relationships between the occurrence, abundance and population trends of coastal birds and environmental factors can be quantitatively assessed using multivariate modelling and model selection. Spatial data sets widely available in Finland can be utilised in the calculation of several variables that are relevant to the habitat selection of Finnish coastal species. Concerning some habitat characteristics field work is still required, due to a lack of remotely sensed data or the low resolution of readily available data in relation to the fine scale of the habitat patches in the archipelago. While long-term data sets exist for water quality and weather, the lack of data concerning for instance the food resources of birds hampers more detailed studies of environmental effects on bird populations. Intensive studies of coastal bird species in different archipelago areas should be encouraged. The provision and free delivery of high-quality coastal data concerning bird populations and their habitats would greatly increase the capability of ecological modelling, as well as the management and conservation of coastal environments and communities. International initiatives that promote open spatial data infrastructures and sharing are therefore highly regarded. To function effectively, international information networks, such as the biodiversity Clearing House Mechanism (CHM) under the CBD, need to be rooted at regional and local levels. Attention should also be paid to the processing of data for higher levels of the information hierarchy, so that data are synthesized and developed into high-quality knowledge applicable to management and conservation.
Resumo:
Työn kirjallisuusosassa selvitettiin eri tekijöiden (lämpötila, paine, mineralogia, partikkelikoko, sekoitus, kiintoainepitoisuus, liuoksen happo-, rauta- ja happipitoisuus) vaikutusta sinkkirikasteen suoraliuotusprosessin tärkeimpiin ilmiöihin (diffuusio, aineensiirto, reaktiokinetiikka). Kirjallisuusosassa kartoitettiin myös tämän hetkistä tietämystä niistä tekijöistä, jotka ovat oleellisia, kun sinkkirikasteen suoraliuotusprosessia mallinnetaan. Näitä tekijöitä ovat: sinkkirikasteiden liuotuksen kemia, sinkkirikasteiden liuotuksen kinetiikka ja mekanismit, kaasuneste aineensiirto ja kiinteäneste aineensiirto. Lisäksi selvitettiin millä tavoin aikaisemmissa tutkimuksissa sinkkirikasteiden suoraliuotusta on mallinnettu. Mallinnusosassa käsiteltiin atmosfääristä sinkkirikasteen suoraliuotusta, jossa hapettimena toimi ferri(III)rauta. Mallintamisessa käytettiin kirjallisuudessa esitettyjä mittaustuloksia ja mallintaminen tehtiin Modest tietokoneohjelmistolla. Työssä tehty atmosfäärisen suoraliuotuksen mallintaminen labo-ratoriomittakaavassa (laimeat liuokset ja pienet kiintoainepitoisuudet) antoi lupaavia tuloksia. Ongelmia mallin ennustuksen kanssa esiintyi pienissä happopitoisuuksissa, alhaisissa lämpötiloissa sekä pienillä ja suurilla partikkeleilla. Työn kirjallisuusosassa tunnistettiin ne ongelmakohdat, jotka vaativat lisätutkimuksia, jotta sinkkirikasteen atmosfääriselle suoraliuotukselle pystytään kehittämään simulointimalli. Näitä ovat: 1. Hapen liukoisuus ja aineensiirto teollisuuden käyttämissä sinkkirikastelietteissä, 2. Sopivien mittaustulosten puuttuminen, jotta atmosfääristä suoraliuotusta, jossa O2 ja Fe3+ toimivat hapettimena voitaisiin mallintaa, 3. Kiinteäneste aineensiirron merkitys sinkkirikasteen suoraliuotuksessa. Mallinnusosassa osoitettiin, että mekanistisella mallintamisella voidaan simuloida sinkkirikasteen atmosfääristä suoraliuotusta ainakin laboratoriomittakaavassa. Työn perusteella voidaan todeta, että sinkkirikasteen atmosfääriselle suoraliuotukselle voidaan työssä ehdotettujen jatkotutkimusten avulla kehittää numeerinen mekanistinen malli, jolla atmosfääristä sinkkirikasteiden suoraliuotusprosessia voidaan simuloida eri olosuhteissa.
Resumo:
Tässä diplomityössä on mallinnettu höyry- ja kaasuturbiini Balas -prosessisimulointi-ohjelmaan. Balas on Valtion Teknillisen Tutkimuskeskuksen kehittämä simulointiohjelma, erityisesti paperi- ja selluteollisuuden prosessien staattiseen simulointiin. Työn tavoitteena on kehittää simulointimallit höyry- ja kaasuturbiinille, sekä tutkia niiden toimivuutta vertaamalla simulointeja mittaus- ja mitoitustietoihin. Työssä on muodostettu matemaattiset mallit höyryturbiinille, höyryturbiinin säätövyöhykkeelle sekä höyryturbiinin off-design laskennalle. Kaasuturbiinille muodostettiin toimintakäyrät, joiden avulla tarkastellaan sen toimintaa off-design tilanteessa. Komponentit mallinnettiin diplomityövaiheessa Matlab-ympäristöön, josta ne siirretään Balasiin erillisessä työvaiheessa. Malleissa on kiinnitetty huomiota erityisesti niiden helppokäyttöisyyteen ja monipuolisuuteen. Höyryturbiinimalleja testattiin simuloimalla erään paperitehtaan yhteydessä toimivan voimalaitoksen vastapaineturbiini säätövyöhykkeineen ja vertaamalla simulointituloksia tehtaan mittaustietoihin. Kaasuturbiinimallia testattiin vertaamalla GE Power MS 7001 kaasuturbiinin mitoitustietoja vastaavilla parametreilla simuloituun tapaukseen.
Resumo:
In liberalized electricity markets, which have taken place in many countries over the world, the electricity distribution companies operate in the competitive conditions. Therefore, accurate information about the customers’ energy consumption plays an essential role for the budget keeping of the distribution company and for correct planning and operation of the distribution network. This master’s thesis is focused on the description of the possible benefits for the electric utilities and residential customers from the automatic meter reading system usage. Major benefits of the AMR, illustrated in the thesis, are distribution network management, power quality monitoring, load modelling, and detection of the illegal usage of the electricity. By the example of the power system state estimation, it was illustrated that even the partial installation of the AMR in the customer side leads to more accurate data about the voltage and power levels in the whole network. The thesis also contains the description of the present situation of the AMR integration in Russia.
Resumo:
The dissertation is based on four articles dealing with recalcitrant lignin water purification. Lignin, a complicated substance and recalcitrant to most treatment technologies, inhibits seriously pulp and paper industry waste management. Therefore, lignin is studied, using WO as a process method for its degradation. A special attention is paid to the improvement in biodegradability and the reduction of lignin content, since they have special importance for any following biological treatment. In most cases wet oxidation is not used as a complete ' mineralization method but as a pre treatment in order to eliminate toxic components and to reduce the high level of organics produced. The combination of wet oxidation with a biological treatment can be a good option due to its effectiveness and its relatively low technology cost. The literature part gives an overview of Advanced Oxidation Processes (AOPs). A hot oxidation process, wet oxidation (WO), is investigated in detail and is the AOP process used in the research. The background and main principles of wet oxidation, its industrial applications, the combination of wet oxidation with other water treatment technologies, principal reactions in WO, and key aspects of modelling and reaction kinetics are presented. There is also given a wood composition and lignin characterization (chemical composition, structure and origin), lignin containing waters, lignin degradation and reuse possibilities, and purification practices for lignin containing waters. The aim of the research was to investigate the effect of the operating conditions of WO, such as temperature, partial pressure of oxygen, pH and initial concentration of wastewater, on the efficiency, and to enhance the process and estimate optimal conditions for WO of recalcitrant lignin waters. Two different waters are studied (a lignin water model solution and debarking water from paper industry) to give as appropriate conditions as possible. Due to the great importance of re using and minimizing the residues of industries, further research is carried out using residual ash of an Estonian power plant as a catalyst in wet oxidation of lignin-containing water. Developing a kinetic model that includes in the prediction such parameters as TOC gives the opportunity to estimate the amount of emerging inorganic substances (degradation rate of waste) and not only the decrease of COD and BOD. The degradation target compound, lignin is included into the model through its COD value (CODligning). Such a kinetic model can be valuable in developing WO treatment processes for lignin containing waters, or other wastewaters containing one or more target compounds. In the first article, wet oxidation of "pure" lignin water was investigated as a model case with the aim of degrading lignin and enhancing water biodegradability. The experiments were performed at various temperatures (110 -190°C), partial oxygen pressures (0.5 -1.5 MPa) and pH (5, 9 and 12). The experiments showed that increasing the temperature notably improved the processes efficiency. 75% lignin reduction was detected at the lowest temperature tested and lignin removal improved to 100% at 190°C. The effect of temperature on the COD removal rate was lower, but clearly detectable. 53% of organics were oxidized at 190°C. The effect of pH occurred mostly on lignin removal. Increasing the pH enhanced the lignin removal efficiency from 60% to nearly 100%. A good biodegradability ratio (over 0.5) was generally achieved. The aim of the second article was to develop a mathematical model for "pure" lignin wet oxidation using lumped characteristics of water (COD, BOD, TOC) and lignin concentration. The model agreed well with the experimental data (R2 = 0.93 at pH 5 and 12) and concentration changes during wet oxidation followed adequately the experimental results. The model also showed correctly the trend of biodegradability (BOD/COD) changes. In the third article, the purpose of the research was to estimate optimal conditions for wet oxidation (WO) of debarking water from the paper industry. The WO experiments were' performed at various temperatures, partial oxygen pressures and pH. The experiments showed that lignin degradation and organics removal are affected remarkably by temperature and pH. 78-97% lignin reduction was detected at different WO conditions. Initial pH 12 caused faster removal of tannins/lignin content; but initial pH 5 was more effective for removal of total organics, represented by COD and TOC. Most of the decrease in organic substances concentrations occurred in the first 60 minutes. The aim of the fourth article was to compare the behaviour of two reaction kinetic models, based on experiments of wet oxidation of industrial debarking water under different conditions. The simpler model took into account only the changes in COD, BOD and TOC; the advanced model was similar to the model used in the second article. Comparing the results of the models, the second model was found to be more suitable for describing the kinetics of wet oxidation of debarking water. The significance of the reactions involved was compared on the basis of the model: for instance, lignin degraded first to other chemically oxidizable compounds rather than directly to biodegradable products. Catalytic wet oxidation of lignin containing waters is briefly presented at the end of the dissertation. Two completely different catalysts were used: a commercial Pt catalyst and waste power plant ash. CWO showed good performance using 1 g/L of residual ash gave lignin removal of 86% and COD removal of 39% at 150°C (a lower temperature and pressure than with WO). It was noted that the ash catalyst caused a remarkable removal rate for lignin degradation already during the pre heating for `zero' time, 58% of lignin was degraded. In general, wet oxidation is not recommended for use as a complete mineralization method, but as a pre treatment phase to eliminate toxic or difficultly biodegradable components and to reduce the high level of organics. Biological treatment is an appropriate post treatment method since easily biodegradable organic matter remains after the WO process. The combination of wet oxidation with subsequent biological treatment can be an effective option for the treatment of lignin containing waters.
Resumo:
Väitöskirjassa tarkastellaan kouluikäisten lasten ja nuorten sosiaalisen kompetenssin ja yksinäisyyden mittaamista, yhteyksiä ja periytyvyyttä vanhemmilta heidän lapsilleen. Alakouluikäisten lasten tutkimusaineisto (n=985) koostuu lapsilta itseltään, heidän luokkatovereiltaan, opettajiltaan ja vanhemmiltaan vuosina 2000 - 2004 osana Merkitystä etsimässä – tutkimusprojektia (M. Vauras) kerätystä aineistosta. Mukana on itse-, toveri-, opettaja- ja vanhempien arviot lasten sosiaalisesta kompetenssista, seuranta-aineisto lasten yksinäisyydestä, opettajien arviot lasten motivationaalisesta orientaatiosta, standardoiduin testisarjoin arvioidut akateemiset taidot sekä lasten äitien ja isien arviot omasta yksinäisyydestään ja koetusta kyvykkyydestään toimia vanhempana. Yläkouluikäisten nuorten (n=386) aineisto koostuu vuosina 2006 – 2007 osana Sosioemotionaalinen oppiminen ja hyvinvointi yläkouluyhteisössä (P. M. Niemi) kerätystä nuorten yksinäisyyden, sosiaalisen ahdistuneisuuden ja sosiaalisen fobian seuranta-aineistosta. Mitattavuutta (päätavoite 1) tutkittiin erityisesti monitahoarviointien rakenteiden yhtenäisyyksiä, subjektiivisten arvioiden ajallista pysyvyyttä sekä mittareiden validiteettia ja reliabiliteettia testaamalla. Sosiaalisen kompetenssin ja yksinäisyyden keskinäisten yhteyksien lisäksi tarkasteltiin näiden yhteyttä alakoululaisten oppimiseen sekä yläkou¬lulaisten psykososiaaliseen hyvinvointiin (päätavoite 2). Kolmantena päätavoitteena oli selvittää yksinäisyyden mahdollista periytymistä vanhemmilta lapsille. Osana ensimmäistä päätavoitetta kehitettiin Monitahoarviointi sosiaalisesta kompetenssista (MASK) -arviointimenetelmä (artikkeli 1). Konfirmatorisen faktorianalyysin tulosten perusteella nelifaktorinen rakenne (prososiaalisuus sisältäen yhteistyötaidot ja empatiakyvyn sekä antisosiaalisuus sisältäen impulsiivisuuden ja häiritsevyyden) sopi sekä lasten itsensä, heidän luokkatovereidensa, opettajiensa että vanhempiensa tekemiin arviointeihin. Eri tahojen arviointien väliset korrelaatiot olivat tilastollisesti merkitseviä, joskin suhteellisen matalia, ts. eri tahojen näkökulmat lapsen sosiaalisesta kompetenssista ovat toisistaan eriäviä. Täten eri arvioitsijatahojen käyttäminen on kokonaisuuden tutkimisen kannalta tärkeää. Toisena mittaamiseen liittyvänä tavoitteena oli validoida Hozan, Bukowskin ja Beeryn (2000) sosiaalisen ja emotionaalisen yksinäisyyden mittari suomalaisille lapsille (artikkeli 3) ja nuorille (artikkeli 4) soveltuvaksi sekä tutkia, ovatko lasten ja nuorten arviot omasta yksinäisyydestään ajallisesti pysyviä. Alakoululaisten lasten osalta yksinäisyys, erityisesti sosiaalinen yksinäisyys osoittautui suhteellisen pysyväksi, mutta vahvistui entisestään yläkouluikäisten nuorten aineistoa tarkasteltaessa. Huomionarvoista sekä ala- että yläkoululaisten aineistoissa oli poikien kokema vahva emotionaalinen yksinäisyys. Molempien mittareiden osalta sekä validiteetti että reliabiliteetti todettiin hyväksyttäväksi ja niitä voidaan suositella lasten ja nuorten sosiaalisen kompetenssin ja yksinäisyyden arviointimenetelmiksi. Toisena päätavoitteena oli rakenneyhtälömallinnuksen keinoin tarkastella sosiaalisen kompetenssin ja yksinäisyyden yhteyksiä sekä keskenään (artikkelit 2 ja 3) että suhteessa lasten oppimiseen (artikkeli 2) ja nuorten psykososiaaliseen hyvinvointiin (artikkeli 4). Alakouluikäisten lasten osalta sosiaalinen kompetenssi oli yhteydessä pait¬si yksinäisyyteen myös opettajien oppilaistaan tekemiin motivationaalisen orientaation arvioihin sekä standardoiduin testien arvioituihin akateemisiin taitoihin. Yläkouluikäisten nuorten osalta yksinäisyys oli yhteydessä sosiaaliseen ahdistuneisuuteen ja sosiaaliseen fobiaan. Täten sosiaalisen kompetenssin voidaan katsoa olevan koululaisten hyvinvointia ja oppimista vahvistava, ja toisaalta yksinäisyyden nuorten psykososiaalista hyvinvointia heikentävä tekijä. Viimeisenä päätavoitteena mallinnettiin yksinäisyyden mahdollista periytyvyyttä. Ensimmäisessä vaiheessa periytyvyyttä tarkasteltiin koko perheen sisällä, vanhempien tai lasten sukupuolta erottelematta (artikkeli 2). Tässä rakenneyhtälömallissa vanhempien kokema yksinäisyys ennusti heikompaa kyvykkyydentunnetta vanhemmuudesta, joka edelleen ennusti lapsen heikompaa toveriarvioitua sosiaalista kompetenssia koulussa ja tätä kautta vahvempaa yksinäisyyden kokemusta. Toisessa mallissa eroteltiin äitien ja isien sekä tyttöjen ja poikien aineistot, jotta periytyvyyttä voitiin tarkastella äiti-tytär, äiti-poika, isä-tytär ja isä-poika dyadisuhteissa. Rakenneyhtälömallinnuksen tulosten perusteella sekä äitien että isien kokema yksinäisyys ennusti
Resumo:
This work presents models and methods that have been used in producing forecasts of population growth. The work is intended to emphasize the reliability bounds of the model forecasts. Leslie model and various versions of logistic population models are presented. References to literature and several studies are given. A lot of relevant methodology has been developed in biological sciences. The Leslie modelling approach involves the use of current trends in mortality,fertility, migration and emigration. The model treats population divided in age groups and the model is given as a recursive system. Other group of models is based on straightforward extrapolation of census data. Trajectories of simple exponential growth function and logistic models are used to produce the forecast. The work presents the basics of Leslie type modelling and the logistic models, including multi- parameter logistic functions. The latter model is also analysed from model reliability point of view. Bayesian approach and MCMC method are used to create error bounds of the model predictions.
Resumo:
Environmental problems and issues have received more and more attention during the last decades. Reasons for this are different increased external costs such as congestion, CO2 emission, noise and accident costs. Transportation sector is the only sector with increasing external costs. The EU will increase its attention in decreasing the external costs of transport. Aim of this research was to find out if a dry port solution could decrease costs of transport, especially external costs. Dry port concept is an intermodal transport system, where inland transport between port and dry port is performed by rail transport instead of traditional road transport. In addition, dry ports offer similar services as ports. Research is conducted by performing a literature review about dry port concept and costs of transport, especially external costs of transport. Financial and environmental impacts of the dry port concept are studied by comparing costs of road and rail transport by cost accounting and with a simulation model. Location of dry port is researched with gravitational models. Results of the literature review are that rail transport is environmentally friendlier mode of transport than road transport. Cost model and simulation model show that if only costs of freight movement are considered, rail transport is more inexpensive transport mode than road transport in terms of internal and external costs. Because of that dry port concept could decrease costs of transport, especially external costs. Results of gravitational models are that city of Kouvola is in a good position to be a dry port. Russian transit traffic through Finland improves location of Kouvola to be a dry port.