Review of combustion indexes remote sensing applied to different combustion types

This paper summarizes the main studies carried out by the authors for the development of indexes for remote combustion sensing applicable to different combustion types, i.e. conventional gasoline and diesel combustions, diesel PCCI and dual fuel gasoline-diesel RCCI. It is well-known that the continuous development of modern Internal Combustion Engine (ICE) management systems is mainly aimed at complying with upcoming increasingly stringent regulations throughout the world, both for pollutants and CO2 emissions. Performing an efficient combustion control is crucial for efficiency increase and pollutant emissions reduction. Over the past years, the authors of this paper have developed several techniques to estimate the most important combustion indexes for combustion control, without using additional cylinder pressure sensors but only using the engine speed sensor (always available on board) and accelerometers (usually available on-board for gasoline engines). In addition, a low-cost sensor based on acoustic sensing can be integrated to support combustion indexes evaluation and other engine relevant information. The real-time calculation of combustion indexes is even more crucial for innovative Low Temperature Combustions (such as diesel PCCI or dual fuel gasoline-diesel RCCI), mainly due to the high instability and the high sensitivity to slight variations of the injection parameters that characterize this kind of combustions. Therefore, the authors of this paper have applied the developed techniques not only to conventional engines (gasoline and diesel combustion), but also to engines modified for Low Temperature Combustions, with promising results in terms of validation and applicability for real-time combustion control. The developed methodologies have been tested and validated through a large amount of experimental tests. To run the estimation algorithms in real-time, they have been all implemented in a specifically designed rapid control prototyping system, the goal being to quantify the accuracy of the estimations and optimize the strategy implementations for the extensive use (in the near future) in modern Engine Control Modules (ECM)

Injection Pattern Investigation for Gasoline Partially Premixed Combustion Analysis

Nowadays, compression-ignited engines are considered the most efficient and reliable technology for automotive applications. However, mainly due to the current emission regulations, that require increasingly stringent reductions of NOx and particulate matter, the use of diesel-like fuels is becoming a critical issue. For this reason, a large amount of research and experimentation is being carried out to investigate innovative combustion techniques suitable to simultaneously mitigate the production of NOx and soot, while improving engine efficiency. In this scenario, the combined use of compression-ignited engines and gasoline-like fuels proved to be very promising, especially in case the fuel is directly-injected in the combustion chamber at high pressure. The presented study analyzes the combustion process produced by the direct injection of small amounts of gasoline in a compression-ignited light-duty engine. The engine under investigation has been modified to guarantee a stable engine operation over its whole operating range, that is achieved controlling boost pressure and temperature, together with the design of the injection pattern. Experimental tests have been performed to highlight the impact of several control variables on the combustion effectiveness, i.e. on combustion efficiency and ignition delay. To identify the main mechanisms which impact the start of the combustion process and the sensitivity to the variation of the main control parameters, several tests have been run, directly-injecting constant amounts of gasoline in a compression ignited engine. These tests have been performed changing intake pressure and temperature (when suitable to maintain combustion stability), fuel pressure and injection timing within the cycle

La alianza del gobierno de Evo Morales y las Fuerzas Armadas en el proceso de transformación del Estado boliviano

The present paper tries to analyze the relation between the governments of Evo Morales and the Bolivian Armed Forces in the period 2005-2010, and to give response to three central questions: does an informal alliance exist between these two actors of the Bolivian politics? In case of existing, which are the institutional, historical, political and economic factors on which it is based? And, finally, which are the costs that this alliance implies? To such ends a succinct analysis of the actors in question will be realized and later the relation will be studied bearing in mind the following elements: the economic politics of the Movement to the Socialism (MAS); the Constituent Assembly, the regional conflicts and the attempts of autonomy; the social policies developed by the government; the concessions that this relation implies; and, the attempts of institutional redefinition of the Armed Forces.El presente trabajo pretende analizar la relación de los gobiernos de Evo Morales con las Fuerzas Armadas Bolivianas en el periodo 2005-2010 y dar respuesta a tres preguntas centrales: ¿Existe una alianza informal entre estos dos actores de la política boliviana? En caso de existir ¿Cuáles son los factores institucionales, históricos, políticos y económicos en que se fundamenta? Y, por último ¿Cuáles son los costos que implica esta alianza? A tales fines se realizará un sucinto análisis de los actores en cuestión y posteriormente se estudiará la relación entre ellos tomando en cuenta los siguientes elementos: la política económica del Movimiento al Socialismo (MAS); la Asamblea Constituyente, los conflictos regionales y los intentos de autonomía; las políticas sociales impulsadas por el gobierno; las concesiones que implica esta relación; y los intentos de redefinición institucional de las Fuerzas Armadas

Evaluation of greenhouse gas emissions and area of organic soils in cropland and grassland in Latvia – integrated National forest inventory data and soil maps approach

ArticleThe aim of the research was to assess distribution of organic soils in farmlands for the time period between 1990 and 2015, as well as to carry out a recalculation of GHG emissions from organic soils in grassland and cropland. We evaluated the area of typical organic soils using digitized soil maps created between 1960s and 1980s there were 183,000 ha of cropland and grassland on organic soils. A selected number of areas on organic soils intersecting with the National forest inventory (NFI) plots were surveyed. We found that 66 ± 10% of surveyed plots still conforms to criteria for organic soils according to Intergovernmental Panel on Climate Change (IPCC) guidelines; in the rest of plots soil organic matter has been mineralized and these areas do not conform to IPCC criteria of organic soils. The following distributionof organic soils was estimated in cropland – 6.3 ± 3.3% in 1990 and 4.1 ± 3.4% in 2015, but in grassland – 11.6 ± 3.6% in 1990 and 7.7 ± 3.9% in 2015. The annual reduction of GHG emissions due to reduction of area of organic soils in cropland in 2015 corresponds to 1,400,000 tonnes CO2 eq. in comparison to 1990 and in grassland – to 1,100,000 tonnes CO2 eq. The estimated reduction of the GHG emissions due to conversion of organic soils into mineral soils, comparing the average value in 2005–2009 with the projection for 2021–2030 on average will correspond to 313,000 tonnes CO2 eq. annually, however LULUCF sector still won’t become a net CO2 sink according to the GHG inventory data on other land use categories and carbon pools

Investigation of Gasoline Partially Premixed Combustion with External Exhaust Gas Recirculation

The stringent emission regulations for Internal Combustion Engines (ICEs) spawned a great amount of research in the field of innovative combustion approaches characterized by high efficiency and low emissions. Previous research demonstrate that such promising techniques, named Low-Temperature Combustion (LTC), combine the benefits of Compression Ignition (CI) engines, such as high compression ratio and unthrottled lean mixture, with low engine-out emissions using a properly premixed air-fuel mixture. Due to longer ignition delay and high volatility compared to diesel, gasoline-like fuels show good potential for the generation of a highly premixed charge, which is needed to reach LTC characteristics. In this scenario, gasoline Partially Premixed Combustion (PPC), characterized by the high-pressure direct injection of gasoline, showed good potential for the simultaneous reduction of pollutants and emissions in CI engines. However, previous research on gasoline CI highlight that a key factor for the optimization of both efficiency and pollutants is the proper management of Exhaust Gas Recirculation (EGR). This work presents the experimental investigation performed running a light-duty CI engine, operated with gasoline PPC, and varying the mass of recirculated gases trapped in the combustion chamber. To guarantee the stability of gasoline autoignition in all the tested conditions, a specific experimental layout has been developed to accurately quantify the amount of trapped residual gases due to the internal and external EGR. The obtained results clearly highlight the impact of EGR on the combustion process and emissions, demonstrating that optimization of charge dilution with EGR is fundamental to guarantee the optimal compromise between efficiency and emissions over the whole operating range

La Teleriabilitazione durante la pandemia da COVID-19: un’indagine dell’Ontario Physiotherapy Association delinea vantaggi e criticità

Il governo dell’Ontario considera prioritaria l’integrazione della assistenza virtuale, per consentire una maggiore accessibilità alle cure da parte di utenti, spesso penalizzati da barriere sociodemografiche. A partire dal 27 aprile 2020 per 3 settimane, è stato condotto in Ontario un sondaggio intervistando 365 soggetti durante la pandemia Covid-19, per valutare l’esperienza maturata dai fisioterapisti con la Teleriabilitazione. Sono emersi vantaggi (continuità di cure, contenimento di costi e spostamenti da parte dei pazienti e criticità (insostituibilità della modalità in presenza per valutazioni o terapie manuali, esigenza di una adeguata alfabetizzazione digitale, scarsa disponibilità di adeguamento delle polizze assicurative). In conclusione, ribadita l’insostituibilità della modalità “in presenza” soprattutto per quel che concerne alcune procedure, la Teleriabilitazione si candida come una modalità utile a ridurre il peso sulle strutture ospedaliere, garantire continuità terapeutica, per la sua capacità di enfatizzare l’apprendimento, lo spirito cooperativo e la partecipazione attiva e consapevole del paziente