44 resultados para medium of instruction


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The dewatering of iron ore concentrates requires large capacity in addition to producing a cake with low moisture content. Such large processes are commonly energy intensive and means to lower the specific energy consumption are needed. Ceramic capillary action disc filters incorporate a novel filter medium enabling the harnessing of capillary action, which results in decreased energy consumption in comparison to traditional filtration technologies. As another benefit, the filter medium is mechanically and chemically more durable than, for example, filter cloths and can, thus, withstand harsh operating conditions and possible regeneration better than other types of filter media. In iron ore dewatering, the regeneration of the filter medium is done through a combination of several techniques: (1) backwashing, (2) ultrasonic cleaning, and (3) acid regeneration. Although it is commonly acknowledged that the filter medium is affected by slurry particles and extraneous compounds, published research, especially in the field of dewatering of mineral concentrates, is scarce. Whereas the regenerative effect of backwashing and ultrasound are more or less mechanical, regeneration with acids is based on chemistry. The chemistry behind the acid regeneration is, naturally, dissolution. The dissolution of iron oxide particles has been extensively studied over several decades but those studies may not necessarily be directly applicable in the regeneration of the filter medium which has undergone interactions with the slurry components. The aim of this thesis was to investigate if free particle dissolution indeed correlates with the regeneration of the filter medium. For this purpose, both free particle dissolution and dissolution of surface adhered particles were studied. The focus was on acidic dissolution of iron oxide particles and on the study of the ceramic filter medium used in the dewatering of iron ore concentrates. The free particle dissolution experiments show that the solubility of synthetic fine grained iron oxide particles in oxalic acid could be explained through linear models accounting for the effects of temperature and acid concentration, whereas the dissolution of a natural magnetite is not so easily explained by such models. In addition, the kinetic experiments performed both support and contradict the work of previous authors: the suitable kinetic model here supports previous research suggesting solid state reduction to be the reaction mechanism of hematite dissolution but the formation of a stable iron oxalate is not supported by the results of this research. Several other dissolution mechanisms have also been suggested for iron oxide dissolution in oxalic acid, indicating that the details of oxalate promoted reductive dissolution are not yet agreed and, in this respect, this research offers added value to the community. The results of the regeneration experiments with the ceramic filter media show that oxalic acid is highly effective in removing iron oxide particles from the surface of the filter medium. The dissolution of those particles did not, however, exhibit the expected behaviour, i.e. complete dissolution. The results of this thesis show that although the regeneration of the ceramic filter medium with acids incorporates the dissolution of slurry particles from the surface of the filter medium, the regeneration cannot be assessed purely based upon free particle dissolution. A steady state, dependent on temperature and on the acid concentration, was observed in the dissolution of particles from the surface even though the limit of solubility of free iron oxide particles had not been reached. Both the regeneration capacity and efficiency, with regards to the removal of iron oxide particles, was found to be temperature dependent, but was not affected by the acid concentration. This observation further suggests that the removal of the surface adhered particles does not follow the dissolution of free particles, which do exhibit a dependency on the acid concentration. In addition, changes in the permeability and in the pore structure of the filter medium were still observed after the bulk concentration of dissolved iron had reached a steady state. Consequently, the regeneration of the filter medium continued after the dissolution of particles from the surface had ceased. This observation suggests that internal changes take place at the final stages of regeneration. The regeneration process could, in theory, be divided into two, possibly overlapping, stages: (1) dissolution of surface-adhered particles, and (2) dissolution of extraneous compounds from within the pore structure. In addition to the fundamental knowledge generated during this thesis, tools to assess the effects of parameters on the regeneration of the ceramic filter medium are needed. It has become clear that the same tools used to estimate the dissolution of free particles cannot be used to estimate the regeneration of a filter medium unless only a robust characterisation of the order of regeneration efficiency is needed.

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The report describes those factors of the future that are related to the growth and needs of Russia, China, and India and that may provide significant internationalisation potential for Uusimaa companies. The report examines the emerging trends and market-entry challenges for each country separately. Additionally, it evaluates the training needs of Uusimaa companies in terms of the current offerings available for education on topics related to Russia, China, and India. The report was created via the Delphi method: experts were interviewed, and both Trendwiki material and the latest literature were used to create a summary of experts’ views, statements, and reasons behind recent developments. This summary of views was sent back to the experts with the objective of reaching consensus synthesising the differing views or, at least, of providing argumentation for the various alternative lines of development. In addition to a number of outside experts and business leaders, all heads of Finpro’s Finland Trade Centers participated in the initial interviews. The summary was commented upon by all Finpro consultants and analysts for Russia, China, and India, with each focusing on his or her own area of expertise. The literature used consisted of reports, listed for each country, and an extensive selection of the most recent newspaper articles. The report was created in January-April 2010. On 22 April 2010 its results were reviewed at the final report presentation in cooperation with the Uusimaa ELY Centre.

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The doctoral study presents a comprehensive analysis of the impact of the institutional environment on the internationalization-based growth strategic choices of small and mediumsized enterprises (SMEs) in emerging economies. In responding to the calls for more research on institutions and international entrepreneurship, this dissertation extends the linkages between the two to the context of emerging economies. The study presents a comprehensive analysis of institutional challenges and their impact on the internationalization of SMEs in emerging economies, particularly in Russia. The research contributes to the adoption of the institution-based view in international entrepreneurship. The dissertation is presented through five research papers. Based on primary and secondary data, the study categorizes the possible sources of institutional influences on internationalization and empirically tests their impact by applying a method triangulation research design. The result of the conducted research is a proposed theoretical model of the institutional impact on the internationalization of SMEs in emerging economies. The model is specifically focused on the growth stage of the entrepreneurial process and considers only its internationalization facet. The research identifies and provides empirical support for the existence of a positive influence of a transparent and supportive regulatory environment, an institutionalized pool of general business knowledge, and collectivistic value orientation on the proclivity of SMEs to internationalize. A level of appreciation of entrepreneurial initiatives in home country and a greater positive institutional gap provide a positive impact on the international performance of SMEs. The research provides contextualized knowledge of the institutional impact on the internationalization of SMEs in Russia. The obtained results present theoretical value in terms of showing how the environmental conditions effect the entrepreneurial internationalization-based growth in emerging economies, providing the methodological insights into the measurement of the institutional effects, and empirically contextualizing the linkage between institutions and internationalization in the Russian business environment. The research also provides value for the business and policy making stakeholders by identifying ways of utilizing the conditions in the external institutional environment.

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Hydraulic head is distributed through a medium with porous aspect. The analysis of hydraulic head from one point to another is used by the Richard's equation. This equation is equivalent to the groundwater ow equation that predicts the volumetric water contents. COMSOL 3.5 is used for computation applying Richard's equation. A rectangle of 100 meters of length and 10 meters of large (depth) with 0,1 m/s fl ux of inlet as source of our fl uid is simulated. The domain have Richards' equation model in two dimension (2D). Hydraulic head increases proportional with moisture content.

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This bachelor's thesis is about to find out to what extent Finnish managers and small and medium sized organizations are willing and able to put employee empowerment into practice and what experiences they have got from employee empowerment as an approach towards job redesign. Some of the top enterprises in the world are known for their empowered employees as a single most important factor for their success and this thesis focuses on introducing the subject to Finnish managers and organizations to find out what benefits, barriers and other thoughts they have about the whole idea of empowered employees in Finnish organization culture. Most notable findings in this thesis are that Finnish managers do think that their organization's employees are capable to work efficiently if their job is extended and the organizations would perform better when right person's job is enriched and he/she is given more power to solve problems.

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This applied linguistic study in the field of second language acquisition investigated the assessment practices of class teachers as well as the challenges and visions of language assessment in bilingual content instruction (CLIL) at primary level in Finnish basic education. Furthermore, pupils’ and their parents’ perceptions of language assessment and LangPerform computer simulations as an alternative, modern assessment method in CLIL contexts were examined. The study was conducted for descriptive and developmental purposes in three phases: 1) a CLIL assessment survey; 2) simulation 1; and 3) simulation 2. All phases had a varying number of participants. The population of this mixed methods study were CLIL class teachers, their pupils and the pupils’ parents. The sampling was multi-staged and based on probability and random sampling. The data were triangulated. Altogether 42 CLIL class teachers nationwide, 109 pupils from the 3rd, 4th and 5th grade as well as 99 parents from two research schools in South-Western Finland participated in the CLIL assessment survey followed by an audio-recorded theme interview of volunteers (10 teachers, 20 pupils and 7 parents). The simulation experimentations 1 and 2 produced 146 pupil and 39 parental questionnaires as well as video interviews of volunteered pupils. The data were analysed both quantitatively using percentages and numerical frequencies and qualitatively employing thematic content analysis. Based on the data, language assessment in primary CLIL is not an established practice. It largely appears to be infrequent, incidental, implicit and based on impressions rather than evidence or the curriculum. The most used assessment methods were teacher observation, bilingual tests and dialogic interaction, and the least used were portfolios, simulations and peer assessment. Although language assessment was generally perceived as important by teachers, a fifth of them did not gather assessment information systematically, and 38% scarcely gave linguistic feedback to pupils. Both pupils and parents wished to receive more information on CLIL language issues; 91% of pupils claimed to receive feedback rarely or occasionally, and 63% of them wished to get more information on their linguistic coping in CLIL subjects. Of the parents, 76% wished to receive more information on the English proficiency of their children and their linguistic development. This may be a response to indirect feedback practices identified in this study. There are several challenges related to assessment; the most notable is the lack of a CLIL curriculum, language objectives and common ground principles of assessment. Three diverse approaches to language in CLIL that appear to affect teachers’ views on language assessment were identified: instrumental (language as a tool), dual (language as a tool and object of learning) and eclectic (miscellaneous views, e.g. affective factors prioritised). LangPerform computer simulations seem to be perceived as an appropriate alternative assessment method in CLIL. It is strongly recommended that the fundamentals for assessment (curricula and language objectives) and a mutual assessment scheme should be determined and stakeholders’ knowledge base of CLIL strengthened. The principles of adequate assessment in primary CLIL are identified as well as several appropriate assessment methods suggested.

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Tämä soveltavan kielitieteen ja kielitaidon arvioinnin toimintatutkimus tarkasteli kieliportfolion ominaisuuksia ja mahdollisuuksia nuorten oppijoiden englannin kielen arvioinnissa kahdessa eri oppimiskontekstissa: englanti oppiaineena (EFL) ja kaksikielinen sisällönopetus (CLIL). Tutkielman itsenäiset, kahteen eri englannin kielen rekisteriin (arkikieli ja akateeminen kieli) kohdistuneet portfoliokokeilut olivat erillisiä tapaustutkimuksia. Molemmat portfoliot perustuivat väljästi Eurooppalaiseen kielisalkkumalliin, ja ne olivat osa tutkielmantekijän luokkaopetusta ja -toimintaa. EFL -portfoliokokeilu 9-10-vuotiaille kolmasluokkalaisille toteutettiin marraskuun 2011 ja toukokuun 2012 välisenä aikana, kun CLIL -portfoliokokeilu n. 7-9-vuotiallle ensimmäisen ja toisen luokan oppilaille kesti kaksi lukuvuotta 2012–2014. Molemmissa kokeiluissa myös oppilaiden vanhemmat kuuluivat tutkimusjoukkoon, samoin CLIL -portfolion toteutuksessa avustaneet ja opettajanäkökulmaa edustaneet opettajaopiskelijat. Portfoliokokeilun aloitti myös kaksi muuta CLIL -opettajaa, mutta kumpikin kokeilu päättyi alkuvaiheeseensa. Tarkemman tarkastelun kohteina olivat tutkimuksen osallistujien kokemukset ja mielipiteet portfoliokokeiluista. Erityisesti tavoitteena oli selvittää, miten informatiivisena englannin kielitaidon indikaattorina kieliportfoliota pidettiin. Myös kehitysehdotuksia kerättiin. Trianguloitu aineisto koottiin sekä puolistrukturoiduin kyselyin että vapaaehtoisin teemahaastatteluin, jotka äänitettiin. EFL -aineisto koostui 18 oppilaskyselystä, 17 huoltajakyselystä ja 7 oppilashaastattelusta. CLIL -aineistoon sisältyi 19 oppilaskyselyä, 18 huoltajakyselyä, 7 oppilashaastattelua ja yksi opettajaopiskelijoiden (N=3) ryhmähaastattelu. Aineisto analysoitiin pääosin kvalitatiivisin menetelmin temaattisen sisältöanalyysin keinoin, mutta myös laskien frekvenssejä ja prosenttisosuuksia. Osallistujien mielipiteet ja kokemukset olivat hyvin samankaltaiset ja positiiviset kummassakin portfoliokokeilussa. Merkittävä enemmistö sekä oppilaista että huoltajista koki, että portfolion avulla on mahdollista osoittaa englannin kielitaitoa ja sen kehittymistä. Oppilaat kuvailivat portfoliotyötä hauskaksi ja kivaksi, ja heidän mielestään portfoliotehtävien pitäisi olla tarpeeksi haastavia, sisältää taiteellisia ja luovia elementtejä sekä kohdistua tuttuihin, mielenkiintoisiin aiheisiin. He totesivat, että portfolion avulla voi oppia lisää kieltä. Vanhempien mielestä portfolio kertoo koulun vieraiksi jääneistä oppisisällöistä, auttaa ymmärtämään lapsen ajatusmaailmaa ja motivaatiotasoa sekä paljastaa heidän kielitaidostaan uusia ulottuvuuksia. Opettajaopiskelijat havaitsivat, että portfolion avulla voi tutustua oppilaiden kieli- ja kulttuuritaustoihin sekä kartoittaa heidän kielellisiä tarpeitaan. Tämän tutkielman teoreettisen tarkastelun ja tulosten mukaan kieliportfolio tukee erinomaisesti uuden Perusopetuksen Opetussuunnitelman (NCC 2014) tavoitteita ja arvioinnin uudistuspyrkimyksiä sekä lainsäädännön arvioinnille asettamia edellytyksiä. Portfolio on erittäin suositeltava nuorten oppijoiden kielitaidon arviointimenetelmä perinteisten rinnalle.

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With small and medium sized-enterprises (SMEs) taking up the majority of the global businesses, it is important they act in an environmentally responsible manner. Environmental management systems (EMS) help companies evaluate and improve their environmental impact but they often require human, financial, and temporary resources that not all SMEs can provide. This research encompasses interviews with representatives of two small enterprises in Germany to provide insights into their understanding, and knowledge of an EMS and how they perceive their responsibility towards the environment. Furthermore, it presents a toolkit created especially for small and medium-sized enterprises that serves as a simplified version of an EMS based on the ISO 14001 standard and is evaluated by the representatives of the SMEs. Some of the findings are: while being open to the idea of improving their environmental impact, SMEs do not always feel it is their responsibility to do so; they seem to lack the means to fully implement an EMS. The developed toolkit is considered useful and usable and recommendations are drawn for its future enhancement.