927 resultados para development strategy
Resumo:
The molecular profiling system was developed using directed terminal-restriction fragment length polymorphism (dT-RFLP) to characterize soil nematode assemblages by relative abundance of feeding guilds and validation by comparison to traditional morphological method. The good performance of these molecular tools applied to soil nematodes assemblages create an opportunity to develop a novel approach for rapid assessment of the biodiversity changes of benthic nematodes assemblages of marine and estuarine sediments. The main aim of this research is to combine morphological and molecular analysis of estuarine nematodes assemblages, to establish a tool for fast assessment of the biodiversity changes within habitat recovery of Zostera noltii seagrass beds; and validate the dT-RFLP as a high-throughput tool to assess the system recovery. It was also proposed to develop a database of sequences related to individuals identified at species level to develop a new taxonomic reference system. A molecular phylogenetic analysis of the estuarine nematodes has being performed. After morphological identification, barcoding of 18S rDNA are being determined for each nematode species and the results have shown a good degree of concordance between traditional morphology-based identification and DNA sequences. The digest strategy developed for soil nematodes is not suitable for marine nematodes. Then five samples were cloned and sequenced and the sequence data was used to design a new dT-RFLP strategy to adapt this tool to marine assemblages. Several solutions were presented by DRAT and tested empirically to select the solution that cuts most efficiently, separating the different clusters. The results of quantitative PCR showed differences in nematode density between two sampling stations according the abundance of the nematode density obtained by the traditional methods. These results suggest that qPCR could be a robust tool for enumeration of nematode abundance, saving time.
Resumo:
Portugal is characterized by a significant asymmetry in the population distribution/density and economic activity as well as in social and cultural dynamics. This means very diverse landscapes, differences in regional development, sustainability and quality of life, mainly between urban and rural areas. A consequence coherent with the contemporary dynamics: urbanization of many rural areas that loose their productive-agricultural identity and, simultaneously, the reintegration in urban areas of spaces and activities with more rural characteristics. In this process of increasing complexity of organization of the landscape is essential to restore the continuum naturale (between urban and rural areas) allowing closer links to both ways of life. A strategy supported in the landscape, which plays important functions for public interest, in the cultural, social, ecological and environmental fields. At the same time, constitutes an important resource for economic activity, as underlined in the European Landscape Convention. Based on this assumption, and using a multi-method approach, the study aims to analyse a) the links between urban and rural areas in Portugal and b) the reasons why these territories are chosen by individuals as places of work and mobility, residence or evasion, culture and leisure, tranquillity or excitement – meaning overall well-being. Primary information was obtained by a questionnaire survey applied to a convenience sample of the Portuguese population. Secondary data and information will be collected on the official Portuguese Statistics (INE and PORDATA). Understanding the urban-rural links is essential to support policy measures, take advantage from the global changes and challenge many of the existing myths.
Resumo:
A shift in the entrepreneurial landscape is taking place brought about by grassroots innovators with little formal education and technological knowhow, living and working in penurious environments. This research represents an emerging third wave of literature on Bottom of the Pyramid innovation, where products are offered for and by the underserved. Using primary and secondary data derived from four cases of grassroots entrepreneurs in the Indian Subcontinent, the study explores the phenomenon where resource scarce entrepreneurs craft solutions that are environmental friendly, with low overall ownership costs, and use locally available material. We argue that the grassroots phenomenon can be fruitfully exploited to achieve the new Sustainable Development Goals proposed by the UN as a post-2015 strategy for the future of global governance. These innovations might have a tremendous impact not only in terms of serving unmet and ignored consumer needs, but also longer term impacts through enhanced productivity, sustainability, poverty reduction and inclusion promotion.
Resumo:
Large-scale agriculture is increasing in anthropogenically modified areas in the Amazon Basin. Crops such as soybean, maize, oil palm, and others are being introduced to supply the world demand for food and energy. However, the current challenge is to enhance the sustainability of these areas by increasing efficiency of production chains and to improve environmental services. The Amazon Basin has experienced a paradigm shift away from the traditional slash-and-burn agricultural practices, which offers decision makers the opportunity to make innovative interventions to enhance the productivity in previously degraded areas by using trees to ecological advantage. This study describes a successful experiment integrating the production of soybean and paricá (Glycine max L. and Schizolobium amazonicum) based on previous research that indicated potential topoclimatic zones for planting paricá in the Brazilian state of Pará. This paper shows that a no-tillage system reduces the effects of drought compared to conventional tillage still used by many farmers in the region. The integrated system was implemented during the 2014/2015 season in 234.6 ha in the high-potential zone in the municipality of Ulianópolis, Pará. Both soybean and paricá were planted simultaneously. Paricá was planted in 5 m x 2 m inter-tree spacing totaling 228x103 trees per hectare and soybean, in 4 m x 100 m spacing, distributed in nine rows with a 0.45 m inter-row distance, occupying 80% of the area. The harvested soybean production was 3.4 t ha-1, higher than other soybean monocultures in eastern Pará. Paricá benefited from soybean fertilization in the first year: It exhibited rapid development in height (3.26 m) and average diameter (3.85 cm). Trees and crop rotation over the following years is six years for forest species and one year for each crop. Our results confirm there are alternatives to the current production systems able to diminish negative impacts resulting from monoculture. In addition, the system provided environmental services such as reduced soil erosion and increased carbon stock by soil cover with no-tillage soybean cultivation. The soybean cover contributes to increased paricá thermal regulation and lower forestry costs. We concluded that innovative interventions are important to show local farmers that it is possible to adapt an agroforest system to large-scale production, thus changing the Amazon.
Resumo:
Language teaching has become a priority in the Costa Rican educational system, considering it as a tool for communication and development of thought. Without language, there is no access to other curriculum disciplinary knowledge. A successful experience conducted some years ago, with students from 4th to 6th grade, was the basis for the design and implementation of a professional development activity addressed to promoting an integration strategy previously adjusted according to the Ministry’s requirements and the existing national regulations. This study is developed in the framework of a qualitative paradigm including research-action and systematization. A purposive sample was selected based on a suitability factor, through which individuals are informed about the strategy, and then the strategy is applied to a group of students from urban-marginal areas. The techniques used include literature review, analysis of curriculum and Ministry’s regulations, application of an in-depth interview, discussions from the course’s participant in a portfolio, and discussions from students to whom the strategy was applied. We analyzed the considerations of teachers and students, as well as the theoretical and regulatory information by triangulation. The study’s conclusion is the necessity of a communicative approach in language teaching and our recommendation is to implement the strategy developed in the Costa Rican classrooms as provided in this paper.
Resumo:
This PhD thesis reports the main activities carried out during the 3 years long “Mechanics and advanced engineering sciences” course, at the Department of Industrial Engineering of the University of Bologna. The research project title is “Development and analysis of high efficiency combustion systems for internal combustion engines” and the main topic is knock, one of the main challenges for boosted gasoline engines. Through experimental campaigns, modelling activity and test bench validation, 4 different aspects have been addressed to tackle the issue. The main path goes towards the definition and calibration of a knock-induced damage model, to be implemented in the on-board control strategy, but also usable for the engine calibration and potentially during the engine design. Ionization current signal capabilities have been investigated to fully replace the pressure sensor, to develop a robust on-board close-loop combustion control strategy, both in knock-free and knock-limited conditions. Water injection is a powerful solution to mitigate knock intensity and exhaust temperature, improving fuel consumption; its capabilities have been modelled and validated at the test bench. Finally, an empiric model is proposed to predict the engine knock response, depending on several operating condition and control parameters, including injected water quantity.
Resumo:
This manuscript reports the overall development of a Ph.D. research project during the “Mechanics and advanced engineering sciences” course at the Department of Industrial Engineering of the University of Bologna. The project is focused on the development of a combustion control system for an innovative Spark Ignited engine layout. In details, the controller is oriented to manage a prototypal engine equipped with a Port Water Injection system. The water injection technology allows an increment of combustion efficiency due to the knock mitigation effect that permits to keep the combustion phasing closer to the optimal position with respect to the traditional layout. At the beginning of the project, the effects and the possible benefits achievable by water injection have been investigated by a focused experimental campaign. Then the data obtained by combustion analysis have been processed to design a control-oriented combustion model. The model identifies the correlation between Spark Advance, combustion phasing and injected water mass, and two different strategies are presented, both based on an analytic and semi-empirical approach and therefore compatible with a real-time application. The model has been implemented in a combustion controller that manages water injection to reach the best achievable combustion efficiency while keeping knock levels under a pre-established threshold. Three different versions of the algorithm are described in detail. This controller has been designed and pre-calibrated in a software-in-the-loop environment and later an experimental validation has been performed with a rapid control prototyping approach to highlight the performance of the system on real set-up. To further make the strategy implementable on an onboard application, an estimation algorithm of combustion phasing, necessary for the controller, has been developed during the last phase of the PhD Course, based on accelerometric signals.
Resumo:
In this thesis, we deal with the design of experiments in the drug development process, focusing on the design of clinical trials for treatment comparisons (Part I) and the design of preclinical laboratory experiments for proteins development and manufacturing (Part II). In Part I we propose a multi-purpose design methodology for sequential clinical trials. We derived optimal allocations of patients to treatments for testing the efficacy of several experimental groups by also taking into account ethical considerations. We first consider exponential responses for survival trials and we then present a unified framework for heteroscedastic experimental groups that encompasses the general ANOVA set-up. The very good performance of the suggested optimal allocations, in terms of both inferential and ethical characteristics, are illustrated analytically and through several numerical examples, also performing comparisons with other designs proposed in the literature. Part II concerns the planning of experiments for processes composed of multiple steps in the context of preclinical drug development and manufacturing. Following the Quality by Design paradigm, the objective of the multi-step design strategy is the definition of the manufacturing design space of the whole process and, as we consider the interactions among the subsequent steps, our proposal ensures the quality and the safety of the final product, by enabling more flexibility and process robustness in the manufacturing.
Resumo:
Nowadays, the spreading of the air pollution crisis enhanced by greenhouse gases emission is leading to the worsening of the global warming. In this context, the transportation sector plays a vital role, since it is responsible for a large part of carbon dioxide production. In order to address these issues, the present thesis deals with the development of advanced control strategies for the energy efficiency optimization of plug-in hybrid electric vehicles (PHEVs), supported by the prediction of future working conditions of the powertrain. In particular, a Dynamic Programming algorithm has been developed for the combined optimization of vehicle energy and battery thermal management. At this aim, the battery temperature and the battery cooling circuit control signal have been considered as an additional state and control variables, respectively. Moreover, an adaptive equivalent consumption minimization strategy (A-ECMS) has been modified to handle zero-emission zones, where engine propulsion is not allowed. Navigation data represent an essential element in the achievement of these tasks. With this aim, a novel simulation and testing environment has been developed during the PhD research activity, as an effective tool to retrieve routing information from map service providers via vehicle-to-everything connectivity. Comparisons between the developed and the reference strategies are made, as well, in order to assess their impact on the vehicle energy consumption. All the activities presented in this doctoral dissertation have been carried out at the Green Mobility Research Lab} (GMRL), a research center resulting from the partnership between the University of Bologna and FEV Italia s.r.l., which represents the industrial partner of the research project.
Resumo:
The present work proposes different approaches to extend the mathematical methods of supervisory energy management used in terrestrial environments to the maritime sector, that diverges in constraints, variables and disturbances. The aim is to find the optimal real-time solution that includes the minimization of a defined track time, while maintaining the classical energetic approach. Starting from analyzing and modelling the powertrain and boat dynamics, the energy economy problem formulation is done, following the mathematical principles behind the optimal control theory. Then, an adaptation aimed in finding a winning strategy for the Monaco Energy Boat Challenge endurance trial is performed via ECMS and A-ECMS control strategies, which lead to a more accurate knowledge of energy sources and boat’s behaviour. The simulations show that the algorithm accomplishes fuel economy and time optimization targets, but the latter adds huge tuning and calculation complexity. In order to assess a practical implementation on real hardware, the knowledge of the previous approaches has been translated into a rule-based algorithm, that let it be run on an embedded CPU. Finally, the algorithm has been tuned and tested in a real-world race scenario, showing promising results.
Resumo:
This master thesis work is focused on the development of a predictive EHC control function for a diesel plug-in hybrid electric vehicle equipped with a EURO 7 compliant exhaust aftertreatment system (EATS), with the purpose of showing the advantages provided by the implementation of a predictive control strategy with respect to a rule-based one. A preliminary step will be the definition of an accurate powertrain and EATS physical model, starting from already existing and validated applications. Then, a rule-based control strategy managing the torque split between the electric motor (EM) and the internal combustion engine (ICE) will be developed and calibrated, with the main target of limiting tailpipe NOx emission by taking into account EM and ICE operating conditions together with EATS conversion efficiency. The information available from vehicle connectivity will be used to reconstruct the future driving scenario, also referred to as electronic horizon (eHorizon), and in particular to predict ICE first start. Based on this knowledge, an EATS pre-heating phase can be planned to avoid low pollutant conversion efficiencies, thus preventing high NOx emission due to engine cold start. Consequently, the final NOx emission over the complete driving cycle will be strongly reduced, allowing to comply with the limits potentially set by the incoming EURO 7 regulation. Moreover, given the same NOx emission target, the gain achieved thanks to the implementation of an EHC predictive control function will allow to consider a simplified EATS layout, thus reducing the related manufacturing cost. The promising results achieved in terms of NOx emission reduction show the effectiveness of the application of a predictive control strategy focused on EATS thermal management and highlight the potential of a complete integration and parallel development of involved vehicle physical systems, control software and connectivity data management.
Resumo:
This thesis is a combination of research questions in development economics and economics of culture, with an emphasis on the role of ancestry, gender and language policies in shaping inequality of opportunities and socio-economic outcomes across different segments of a society. The first chapter shows both theoretically and empirically that heterogeneity in risk attitudes can be traced to the ethnic origins and ancestral way of living. In particular, I construct a measure of historical nomadism at the ethnicity level and link it to contemporary individual-level data on various proxies of risk attitudes. I exploit exogenous variation in biodiversity to build a novel instrument for nomadism: distance to domestication points. I find that descendants of ethnic groups that historically practiced nomadism (i) are more willing to take risks, (ii) value security less, and (iii) have riskier health behavior. The second chapter evaluates the nature of a trade-off between the advantages of female labor participation and the positive effects of female education. This work exploits a triple difference identification strategy relying on exogenous spike in cotton price and spatial variation in suitability for cotton, and split sample analyses based on the exogenous allocation of land contracts. Results show that gender differences in parental investments in patriarchal societies can be reinforced by the type of agricultural activity, while positive economic shocks may further exacerbate this bias, additionally crowding out higher possibilities to invest in female education. The third chapter brings novel evidence of the role of the language policy in building national sentiments, affecting educational and occupational choices. Here I focus on the case of Uzbekistan and estimate the effects of exposure to the Latin alphabet on informational literacy, education and career choices. I show that alphabet change affects people's informational literacy and the formation of certain educational and labour market trends.
Resumo:
The aim of the Ph.D. research project was to explore Dual Fuel combustion and hybridization. Natural gas-diesel Dual Fuel combustion was experimentally investigated on a 4-Stroke, 2.8 L, turbocharged, light-duty Diesel engine, considering four operating points in the range between low to medium-high loads at 3000 rpm. Then, a numerical analysis was carried out using a customized version of the KIVA-3V code, in order to optimize the diesel injection strategy of the highest investigated load. A second KIVA-3V model was used to analyse the interchangeability between natural gas and biogas on an intermediate operating point. Since natural gas-diesel Dual Fuel combustion suffers from poor combustion efficiency at low loads, the effects of hydrogen enriched natural gas on Dual Fuel combustion were investigated using a validated Ansys Forte model, followed by an optimization of the diesel injection strategy and a sensitivity analysis to the swirl ratio, on the lowest investigated load. Since one of the main issues of Low Temperature Combustion engines is the low power density, 2-Stroke engines, thanks to the double frequency compared to 4-Stroke engines, may be more suitable to operate in Dual Fuel mode. Therefore, the application of gasoline-diesel Dual Fuel combustion to a modern 2-Stroke Diesel engine was analysed, starting from the investigation of gasoline injection and mixture formation. As far as hybridization is concerned, a MATLAB-Simulink model was built to compare a conventional (combustion) and a parallel-hybrid powertrain applied to a Formula SAE race car.
Resumo:
Persistent food insecurity and famines have continued to significantly shape the development policies of Ethiopia for decades. Over the decades, frequent famines caused not only the death of hundreds of thousands of victims but also significantly contributed to two revolutions that swept away the Haile Selassie and Derg regimes, as well as significantly taxing the legitimacy of the incumbent regime. As a result, agriculture and food security have become increasingly the top policy priorities for all political regimes in Ethiopia. However, the development policies of the ruling elites of Ethiopia have consistently failed to transform backward agriculture and ensure food security. The failures of the development policies of the Ethiopian governments over the years were attributed to several factors. Ethiopian authoritarian politics, centralized rule with a lack of transparency and accountability; the isolation of peasants from the development and governance process, and the lack of coherent agricultural development strategies that invest in peasant agriculture and create synergy among sectors are identified as key issues that have contributed to the persistence of food insecurity in the country. The literature on the failure of Ethiopia's political regimes to address food insecurity and famine has two major gaps that this study aims to fill. First, the cumulative and path-dependent food security and agricultural development policy environment were not adequately considered. Second, the strategy of extraversion by subsequent political regimes to use external support as a relief to prevent the famine-induced political crisis. This study used a mixed approach to collect data and present the evolution of the interplays of development policies and food security in three regimes within the context of international food security discourses. This study found out how the historical patterns of approaches of Ethiopia’s regimes to development and governance led to frequent famines and persistent food insecurity.
Resumo:
Aedes albopictus is a vector able to transmit several arboviruses. Due to its high impact on human health, it is important to develop an efficient control strategy for this pest. Nowadays, control based on chemical insecticides is limited by the number of available active principles and the occurrence of resistance. A valuable alternative to the conventional control strategies is the sterile insect technique (SIT) which relies on releasing sterile males of the target insect. Mating between wild females and sterile males results in no viable offspring. A crucial aspect of SIT is the production of a large number of sterile males with a low presence of females that can bite and transmit viruses. The present thesis aimed to find, implement and study the most reliable mechanical sex sorter and protocol to implement male productivity and reduce female contamination. In addition, I evaluated different variables and sorting protocols to enable female recovery for breeding purposes. Furthermore, I studied the creation of a hyper-protandric strain potentially able to produce only males. I also assessed the integration of artificial intelligence with an optical unit to identify sexes at the adult stage. All these applications helped to realise a mass production model in Italy with a potential weekly production of 1 million males. Moreover, I studied and applied for aerial sterile male release in an urban environment. This technology could allow the release of males in a wide area, overcoming environmental and urban obstacles. However, the development and application of drone technologies in a metropolitan area close to airports, such as in Bologna area, must fit specific requirements. Lastly, at Réunion Island, during a Short Term Scientific Mission France (AIM-COST Action), Indian Ocean, I studied the Boosted SIT application. Coating sterile males with Pyriproxyfen may help spread the insecticide into the larval breeding sites.