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Ostrava in the Moravian-Silesian region (Czech Republic) is a European air pollution hot spot for airborne particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), and ultrafine particles (UFPs). Air pollution source apportionment is essential for implementation of successful abatement strategies. UFPs or nanoparticles of diameter <100 nm exhibit the highest deposition efficiency in human lungs. To permit apportionment of PM sources at the hot-spot including nanoparticles, Positive Matrix Factorization (PMF) was applied to highly time resolved particle number size distributions (NSD, 14 nm-10 μm) and PM0.09-1.15 chemical composition. Diurnal patterns, meteorological variables, gaseous pollutants, organic markers, and associations between the NSD factors and chemical composition factors were used to identify the pollution sources. The PMF on the NSD reveals two factors in the ultrafine size range: industrial UFPs (28%, number mode diameter - NMD 45 nm), industrial/fresh road traffic nanoparticles (26%, NMD 26 nm); three factors in the accumulation size range: urban background (24%, NMD 93 nm), coal burning (14%, volume mode diameter - VMD 0.5 μm), regional pollution (3%, VMD 0.8 μm) and one factor in the coarse size range: industrial coarse particles/road dust (2%, VMD 5 μm). The PMF analysis of PM0.09-1.15 revealed four factors: SIA/CC/BB (52%), road dust (18%), sinter/steel (16%), iron production (16%). The factors in the ultrafine size range resolved with NSD have a positive correlation with sinter/steel production and iron production factors resolved with chemical composition. Coal combustion factor resolved with NSD has moderate correlation with SIA/CC/BB factor. The organic markers homohopanes correlate with coal combustion and the levoglucosan correlates with urban background. The PMF applications to NSD and chemical composition datasets are complementary. PAHs in PM1 were found to be associated with coal combustion factor.

In a paper published fifteen years ago, Gorman et al. (Nature 391, 479–481) made precise claims about how sensitive the African wild dog is to kleptoparasitism by spotted hyaenas Crocuta crocuta and lions Panthera leo. These claims are regularly referred to in the literature, and so far, they have remained unchallenged. However, careful perusal of their paper and analysis of the available data on energy intake and expenditure by wild dogs show that their claims are unfounded. Contrary to Gorman et al., wild dogs can usually take loss of food by kleptoparasitism in their stride. We present the calculations of the energy budget of wild dogs that remain implicit in the paper by Gorman et al.

This paper presents a mechanism for developing knowledge based support for real time application of multiagent systems (MAS) in control, automation and diagnosis of electric power systems. In particular it presents a way for autonomous agents to utilize a qualitative means-ends based model for reasoning about control situations. The proposed mechanism has been used in different scenarios of electric power distribution system protection and control. Results show that agents can use local models of their environment and coordinate with other agents to analyze and understand a disturbance situation and choose an appropriate control action. The paper also elaborates on real time interfacing between multi-agent systems and industry standard distribution automation and control system.

In themediumtolongterm,lowfossilfuelavailabilitywillmakeitnecessarytofindalternatives.Mass productionofbiofuelswillnotbeapracticalsolutionbecauseitrequiresstrongcompetitionforland that isusedforgrowingfood.Therefore,itwillbenecessarytorevisetheframeoftransportation energy sources.Thenumberofpurelight-andheavy-dutyelectricvehiclescouldincreaseinurban areas.Instead,itwillbehardtofindaviablealternativetotheinternalcombustionengineforextra- urban transportvehicles,thereforealternativesyntheticfuelscouldbeusedtocompensateforfossil fuel depletion.Asidefromasmallshareobtainablefrombiomass,mostsyntheticfuelsareexpectedto be obtainedfromcoal.Amongthese,syntheticnaturalgasrepresentsaverygoodsolution.Infact, syntheticnaturalgaswillbeadvantageouswithrespecttohydrogen,whoseon-boardstoragewillbean unsolvedprobleminthemediumterm,andwithrespecttosyntheticliquidfuels,whichrequiremore energy intheproductionphase.Moreover,thecarboncontentofliquidfuels,whichishigherthanthat of gaseousfuels,willberesponsibleforhigherCO2 emissionsfromvehicles.Currently,naturalgashas poor diffusioninthetransportsector,andthispaperhighlightsthemotivationsforfavouringapolicy aimedatincreasingtheshareofgaseousfuel-poweredvehicles.Inadditiontothelowenvironmental impact,syntheticnaturalgasalsooffersthepossibilityofoptimisingtheutilisationoffutureresources

This paper proposes a decision tree (DT) based systematic approach for cooperative online power system dynamic security assessment (DSA) and preventive control. This approach adopts a new methodology that trains two contingency oriented DTs on daily basis by the databases generated from power system simulations. Fed with real-time wide area measurements, one DT about measurable variables is employed for online DSA to identify potential security issues and the other DT about controllable variables provides online decision support on preventive control strategies against those issues. A cost effective algorithm is adopted in this proposed approach to optimize the trajectory of preventive control. The paper also proposes an importance sampling algorithm on database preparation for efficient DT training for power systems with high penetration of wind power and distributed generation. The performance of the approach is demonstrated on a 400-bus, 200-line operational model of western Danish power system.

The paper presents a method of analysis and design of urban landscapes called PlaceMaker. The method is intended as a key resource for assessing the identity of places and measures for its enhancement, reconstruction and design. By using different tools for analysis and interpretation of places and questionnaires administered to their users, PlaceMaker finds the identity material that the city has available and how to de-compose and re-compose it for its sustainable project transformation. Pedestrian-intensive areas, in particular urban, cultural and historical poles of attraction, increasingly bear the imprint of globalization, conveying messages which have developed in an uncontrolled manner and are aimed at conveying their users' patterns of thought and action. The presence of a dense mixture of contrasting elements and perceptions can detract from the image of a city. As regards, the paper is completed with a synopsis of the experiment carried out in an historic axe in London - Oxford Street - where globalization is in danger of levelling out the beauty of the area in favour of widespread genericity

Great efforts have been paid to improve engine efficiency as well as to reduce the pollutant emissions. The direct injection allows to improve the engine efficiency; on the other hand, the GDI combustion produces larger particle emissions. The properties of fuels play an important role both on engine performance and pollutant emissions. In particular, great attention was paid to the octane number. Oxygenated compounds allow increasing gasoline's octane number and play an important role in PM emission reduction. In this study was analyzed the effect of fuels with different RON and with ethanol and ethers content. The analysis was performed on a small GDI engine. Two operating conditions, representative of the typical EUDC cycle, were investigated. Both the engine performance and the exhaust emissions were evaluated. The gaseous emissions and particle concentration were measured at the exhaust by means of conventional instruments. Particle size distribution function was measured in the range from 5.6 nm to 560 nm by means of an Engine Exhaust Particle Sizer (EEPS). The results point out that the better result in terms of performance and emission reduction was observed for the high RON fuel. The fuels with ethanol as additive show a large fuel consumption and a not valuable effect on exhaust emissions