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This paper investigates whether national and entrepreneurial framework conditions positively affect economic growth via its effects on entrepreneurial activity more significantly than via its effects on technological innovation intensity1 . The revised GEM conceptual model is tested for a sample of Nordic countries (Norway, Finland, Sweden, Denmark, Iceland), between the years 2005-2014, using path analysis. The variables representing national and entrepreneurial framework conditions, entrepreneurial activity, technological innovation intensity and economic growth are Global Competitiveness Index (which includes also number of procedures to start a business and number of days to start a business, venture capital availability etc.), selfemployed workers (expressed as % of total employed), RD expenditures (expressed as % of GDP) and GDP per capita. In each of the models, the author finds out a positive effect of national and entrepreneurial framework conditions. The hypotheses stating the positive indirect influence of national and entrepreneurial framework conditions on economic growth via entrepreneurial activity (H1) and the positive indirect influence of national and entrepreneurial framework conditions via technological innovation intensity (H2) have been accepted. The calculated total effect on economic growth indicates that the path via entrepreneurship (H1) is more significant (H3).

Este trabalho buscou investigar os principais determinantes da produtividade. Para tanto, o trabalho construiu medidas da Produtividade Total dos Fatores (PTF) e analisou o impacto do Global Competitiveness Index (GCI), de seus subíndices e dos 12 pilares de competitividade que compõem esses subíndices, sobre a PTF. Os principais resultados encontrados são: a heterogeneidade não observada dos países é correlacionada com os regressores, causando estimativas inconsistentes caso não seja tratada; as variáveis apresentaram endogeneidade nos modelos, a qual também deve ser levada em consideração nas estimações; a produtividade passada se mostrou relevante para explicar seu comportamento futuro; os pilares \"ambiente macroeconômico\", \"saúde e ensino básico\" e \"desenvolvimento do mercado financeiro\" afetam positivamente a PTF; já a \"capacidade de absorção tecnológica\" apresentou efeito líquido negativo sobre a PTF, ao contrário do que era esperado; os subíndices apresentaram poucos resultados estatisticamente significantes e em linha com o esperado; e, por último, a análise do índice GCI revelou que um aumento em uma unidade desse indicador, em uma escala de 1 a 7, está relacionado a um crescimento líquido de 21% na produtividade / This study aimed to investigate the main determinants of productivity. Therefore, the work built measures of Total Factor Productivity (TFP) and analyzed the impact of the Global Competitiveness Index (GCI), its subindexes and the 12 pillars of competitiveness that make up these subindexes on the PTF. The main results are: the unobserved heterogeneity of countries is related to the covariates, causing inconsistent estimates if not treated; the variables presented endogeneity in the models, which should also be taken into account in the estimation; productivity lags proved relevant to explain their future behavior; the pillars \"macroeconomic environment\", \"health and basic education\" and \"financial market development\" positively affect the TFP; on the other hand, \"technological readiness\" had a negative net effect on TFP, contrary to what was expected; the subindexes showed few statistically significant results and in line with what was expected; and finally, the analysis of the GCI index revealed that an increase in one unit of this indicator, on a 1 to 7 scale, is related to a net increase of 21% in productivity

Este trabalho buscou investigar os principais determinantes da produtividade. Para tanto, o trabalho construiu medidas da Produtividade Total dos Fatores (PTF) e analisou o impacto do Global Competitiveness Index (GCI), de seus subíndices e dos 12 pilares de competitividade que compõem esses subíndices, sobre a PTF. Os principais resultados encontrados são: a heterogeneidade não observada dos países é correlacionada com os regressores, causando estimativas inconsistentes caso não seja tratada; as variáveis apresentaram endogeneidade nos modelos, a qual também deve ser levada em consideração nas estimações; a produtividade passada se mostrou relevante para explicar seu comportamento futuro; os pilares \"ambiente macroeconômico\", \"saúde e ensino básico\" e \"desenvolvimento do mercado financeiro\" afetam positivamente a PTF; já a \"capacidade de absorção tecnológica\" apresentou efeito líquido negativo sobre a PTF, ao contrário do que era esperado; os subíndices apresentaram poucos resultados estatisticamente significantes e em linha com o esperado; e, por último, a análise do índice GCI revelou que um aumento em uma unidade desse indicador, em uma escala de 1 a 7, está relacionado a um crescimento líquido de 21% na produtividade / This study aimed to investigate the main determinants of productivity. Therefore, the work built measures of Total Factor Productivity (TFP) and analyzed the impact of the Global Competitiveness Index (GCI), its subindexes and the 12 pillars of competitiveness that make up these subindexes on the PTF. The main results are: the unobserved heterogeneity of countries is related to the covariates, causing inconsistent estimates if not treated; the variables presented endogeneity in the models, which should also be taken into account in the estimation; productivity lags proved relevant to explain their future behavior; the pillars \"macroeconomic environment\", \"health and basic education\" and \"financial market development\" positively affect the TFP; on the other hand, \"technological readiness\" had a negative net effect on TFP, contrary to what was expected; the subindexes showed few statistically significant results and in line with what was expected; and finally, the analysis of the GCI index revealed that an increase in one unit of this indicator, on a 1 to 7 scale, is related to a net increase of 21% in productivity

We identify a general property of concrete domains that is sufficient for proving decidability of DLs equipped with them and GCIs. We show that some useful concrete domains, such as temporal one based on the Allen relations and a spatial one based on the RCC-8 relations, have this property. Then, we present a tableau algorithm for reasoning in DLs equipped with such concrete domains.

Recently, it has been shown that the small DL EL, which allows for conjunction and existential restrictions, has better algorithmic properties than its counterpart FL₀, which allows for conjunction and value restrictions. Whereas the subsumption problem in FL₀ becomes already intractable in the presence of aclyc TBoxes, it remains tractable in EL even w.r.t. general concept inclusion axioms (GCIs). On the one hand, we will extend the positive result for EL by identifying a set of expressive means that can be added to EL without sacrificing tractability. On the other hand, we will show that basically all other additions of typical DL constructors to EL with GCIs make subsumption intractable, and in most cases even EXPTIME-complete. In addition, we will show that subsumption in FL₀ with GCIs is EXPTIME-complete.

The latest spillway in Bergeforsen was finished in 2014. It has a 25 metres wide spillway opening capable of discharging 1500 m^3/s at full reservoir retention level. The overflow chute ends in a 35 metres wide and 100 metres long stilling basin which then converges into 25 metres wide curved tunnel leading the water flow under a railway and back into the river. During the winter, the water in the stilling basin and the tunnel freezes, creating an ice cover all the way through the channel and limiting the water passage in the tunnel. For thinner ice covers, the channel can be flushed by discharging water into the spillway, but there are concerns that a colder winter might result in a ice cover of significant thickness, not prone to cracking at water discharges. This could result in water masses flowing on top of the ice cover into an ice covered tunnel leaving it at risk of being pressurized, posing some serious safety threats to the tunnel. This report presents a full-scale 3D model of the spillway with an ice cover as well as both transient and steady-state simulation results for several discharges to examine the effect of an impenetrable ice cover in the channel. The model is verified using American Society of Mechanical Engineers policy complete with an grid convergence index study. It was found that there was no risk for pressurized flow in the tunnel. However, serious wave-run ups was observed at the tunnel entrance and in the tunnel. / <p>Slutrapporten i projektkursen F7042T (15 hp) på civilingenjörsprogrammet i Teknisk fysik och elektroteknik (INTE EXJOBB).</p>

Fuel mixture formation and spray characteristics are crucial for the advancement of Gasoline Compression Ignition (GCI) engine. For investigations of spray characteristics, a high-pressure high-temperature spray chamber with constant volume has been designed, tested and commissioned at CCRC, KAUST. Back light illumination technique has been applied to investigate the macroscopic spray properties of an outwardly opening piezoelec- tric injector. Three parameters including injection pressure, ambient pressure, and ambient temperature have been involved. A total of 18 combinations of experimental conditions were tested under non-reactive conditions. Through qualitative analysis of spray morphology under different operating conditions, an apparent distinction of spray morphology has been noticed. Spray morphology and propagation have shown strong dependencies on ambient pressure and ambient tempera- ture while injection pressure has a negligible effect on spray shape. Increasingly compact and bushier spray patterns were observed in the cases of high ambient pressure due to in- creasing aerodynamic drag force on spray boundary. It should also be noted that ambient temperature plays a fairly important role in fuel evaporation rate. At 200 °C, oscillating and considerably short spray shape was produced. Also, circumferential ring-like vortices and distinctive string-like structures have been identified for the fuel spray exiting this hollow cone injector. It has been observed that high ambient pressure conditions (Pamb = 4 bar and 10.5 bar) are favorable to the vortices generation, which has also been reported in previous literature. The quantitative description of macroscopic spray properties reveals that ambient pres- sure and ambient temperature are found to be the most influential parameters on liquid penetration length. The rise of ambient pressure results in considerably shorter liquid pen- etration length. Ambient temperature also appears to be a very effective factor of reducing penetration length. Injection pressure contributes to a notable increase of liquid penetra- tion length under ambient pressure of 1 atm. However, the influence of injection pressure is substantially reduced under ambient pressures of 4 bar and 10.5 bar, which indicates that ambient pressure exerts much stronger influence than injection pressure on liquid penetra- tion length. Furthermore, it has been revealed that the increase of injection pressure and ambient pressure are the predominant sources contributing to the enlargement of spray cone angle. The effect of injection pressure on spray cone angle has been amplified by the increase of ambient pressure. With increasing ambient pressure, the penetration of injected fuel tends to propagate axially in a much slower manner that leads to wider fuel distribution in the radial direction. Ambient temperature exerts a similar influence on spray cone angle as on liquid penetration length. The spray cone angle experiences a noticeable decline when ambient gas is increased to 200 °C.

<p>Bokens sid 1-6 samt 108- inskannade. Hjalmar Lings teckningar av gymnastiska rörelser av intresse.</p>

Gasoline compression ignition (GCI) engines show promise in meeting stringent new environmental regulations, as they are characterized by high efficiency and low emissions. Simulations using chemical kinetic models provide an important platform for investigating the behaviors of the fuels inside these engines. However, because real fuels are complex, simulations require surrogate mixtures of small numbers of species that can replicate the properties of real fuels. Accordingly, the development of high fidelity, well-validated kinetic models for surrogates is critical in order to accurately replicate the combustion chemistry of different fuels under engine-related conditions. This work focuses on the development of combustion kinetic models to better understand gasoline fuel combustion in GCI engines. An updated iso-octane detailed kinetic model was developed based on new thermodynamic group values and recently evaluated rate coefficients from literature. The model was validated against a wide range of experimental data and conditions. The iso-octane model was further used in 0D simulations for a homogeneous charge compression ignition (HCCI) engine. The results showed that the low-temperature heat release in engines increases with engine boosting when the addition of alky radicals to molecular oxygen is more favored. Ethanol addition was also found to act as a radical sink which inhibits the radical pool formation and results in lower reactivity. Although detailed models provide clarification of the combustion chemistry, their high computational cost impedes their utilization in 3-D engine simulations. Hence, a reduced model for toluene primary reference fuels was developed and validated against ignition delay time and flame speed experiments from literature. The model was then used in numerically investigating the effects of the fuel’s physical properties using hollow-cone and multi-hole injectors in a partially premixed compression ignition (PPCI) engine. It was concluded that the effects of physical properties are evident in multi-hole injection cases, which is attributable to the differences in mixture stratification. Finally, reduced models for multi-components surrogates for three full-blend fuels (light naphtha-Haltermann straight-run naphtha and GCI fuels) were developed. The models were validated against ignition delay time experiments from the literature and tested in 3D engine simulations.