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Ageing and personal retirement savings plan participation with heterogeneity in preferences: The Portuguese case
This paper analyses the relationship between ageing and personal retirement savings plan participation in the Portuguese population, taking into account heterogeneity and endogeneity in preferences. A mixed logit model is used to analyse the determinants of retirement saving behaviour, allowing for heterogeneity and endogeneity in the responses. We find considerable heterogeneity among individuals (in terms of socio-economic variables such as age, gender and income), which must be taken into account by any policy aimed at changing retirement saving behaviour
Sciences and audiences along the lastcentury: the impact of Astronomy Education
Just as in the past, the development of the natural sciences and in particular of astronomy has changed the history of humanity. If we think about the role of our discipline into the future, it shows its enormous power in the field of education, owing to the possibility of awakening interest in science in very varied audiences. Within the framework of the enormous progress made in the technologies related to astronomy, many of them of daily use, the role of the astronomer in the era of Communications acquires fundamental importance. In this presentation, we will try to make a journey through the different ways of presenting astronomical topics for different audiences over the last 100 years. In turn, we will show some specific achievements, associated with education programmes of the discipline. We discuss the impact produced by proposals that are both rigorous in terms of content, and also appeal to the development of the human being in an integral manner, within the framework of citizen science activities. For this research, we have taken into account the uninterrupted development of the NASE programme, which has performed 112 courses in 24 countries throughout the world and in different languages. NASE has involved 4966 secondary teachers in the last eight years.Fil: Barros, Rosario Magdalena. Universidad Politécnica de Catalunya; EspañaFil: Garcia, Beatriz Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa pque. Centenario. Instituto de Tecnología en Detección y Astropartículas. Itedam - subsede del Instituto de tec. En Detección y Astropartículas Mendoza | Comisión Nacional de Energía Atómica. Instituto de Tecnología en Detección y Astropartículas. Itedam - subsede del instituto de tec. En Detección y Astropartículas Mendoza | Universidad Nacional de san Martín. Instituto de Tecnología en Detección y Astropartículas. Itedam - subsede del instituto de tec. En Detección y Astropartículas Mendoza; ArgentinaInternational Astronomical Union SymposiumVienaAustriaInternational Astronomical Unio
A Block-based Programming Approach
Publisher Copyright: Copyright © 2022 by SCITEPRESS – Science and Technology Publications, Lda. All rights reserved.Simple computer activities have been used for a long time for cognitive and physical training in the context of rehabilitation or mental stimulation. An example is training the skills needed by users with special needs to access the computer through scanning access, which is an access method used by persons with major motor difficulties. The increased availability of less expensive mobile devices with large displays provides an ideal platform for these applications. This work-in-progress paper presents an ongoing work to empower rehabilitation therapists and special education teachers with no previous computer programming experience with a set of highly configurable apps supporting several types of activities for scanning access training. The apps are made available as open projects written in a block-based programming language. This way, they may be configurable by non-programmers while also allowing further changes depending on the programming skills of each rehabilitation therapist or special education teacher. This study intends to validate this approach among this group of users and formulate a set of guidelines concerning software architecture and organization and user interaction, to be used in the development of this kind of application.publishersversionpublishe
Context-aware Assessment Using QR-codes
In this paper we present the implementation of a general mechanism to deliver tests based on mobile devices and matrix codes. The system is an extension of Siette, and has not been specifically developed for any subject matter. To evaluate the performance of the system and show some of its capabilities, we have developed a test for a second-year college course on Botany at the School of Forestry Engineering. Students were equipped with iPads and took an outdoor test on plant species identification. All students were able to take and complete the test in a reasonable time. Opinions expressed anonymously by the students in a survey about the usability of the system and the usefulness of the test were very favorable. We think that the application presented in this paper can broaden the applicability of automatic assessment techniques.The presentation of this work has been co-founded by the Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Applying Monte Carlo simulation in predicting costs of manufacturing companies : the case of companhia Vale do Rio Doce
A necessidade de decisões qualificadas no ambiente empresarial gera demandas pelo uso de métodos matemáticos e estatísticos no auxílio ao processo decisório. Nesse contexto, o presente artigo objetiva testar a aplicabilidade do Método de Simulação de Monte Carlo para prever variações nos custos de produção em um período pós-privatização. Para realizar o experimento foi escolhida a Companhia Vale do Rio Doce – CVRD, considerando a sua privatização ocorrida em 1997. Os dados das variáveis analisadas foram extraídos das demonstrações contábeis publicadas entre 1990 e 2004. Os custos de produção (CPV) são simulados em duas aplicações do Método: aplicação que desconsidera os efeitos da privatização e aplicação que considera, no período pós privatização, a redução de custos variáveis e o incremento de receitas operacionais. Em um processo de privatização, esses efeitos são esperados e foram estimados por meio de regressões lineares em estudo anterior de Oliveira e Lustosa (2007). Para verificar a capacidade preditiva do método são realizadas análises comparativas, por meio de testes estatísticos de médias, entre as amostras reais e as amostras simuladas do período pós-privatização. Os resultados obtidos evidenciam a adequação do Método na previsão dos custos de produção e consequente auxílio ao processo decisório. _________________________________________________________________________________ ABSTRACTThe need for qualified decisions in business environment creates demands for the use of mathematical and statistical methods to assist the decisional process. In this context, this article aims to test the applicability of the method of Monte Carlo simulation to predict changes in production costs in a post-privatization period. To perform the experiment Companhia Vale do Rio Doce - CVRD was chosen, considering its privatization that occurred in 1997. The analyzed variables data were extracted from published financial statements between 1990 and 2004. Production costs (CPV) are simulated in two applications of the method: an application that ignores the effects of privatization and implementation that considers the period after privatization, the reduction of variable costs and the income operating increase. In a privatization process, these effects are expected and were estimated by linear regressions in a previous study by Lustosa and Oliveira (2007). To verify the predictive ability of the method comparative analysis are performed, using statistical tests of means between the real samples and the post-privatization period simulated samples. The results show the suitability of the method in predicting the production costs and consequently assisting the decisional process
Analysing the Technical Efficiency of the Spanish Football League First Division with a Random Frontier Model
This paper analyses technical efficiency of football clubs in the Spanish Football League Division 1 (Primera Liga) from the seasons 1995/96-2004/05 with an unbalanced panel data. The random frontier model is used allowing the identification of random variables in the cost frontier. It is concluded that the price of capital-investment, the number of points won and attendance are heterogeneous variables. Therefore, no common public policy aiming to improve efficiency can embrace all of the clubs, so that policies by clusters are required
O uso de habitat pela comunidade de Corujas (Strigidae) em uma Floresta de Terra Firme na Amazônia Central, Brasil
Some structural features of environment are relevant for bird’s survivor, such as food availability, nesting places or shelters may influence in the structure of bird communities. The main goal of this study was to describe spatial distribution and the effects of the forest structural components on the habitat use and structure of the owl’s community (Otus watsonii, Lophostrix cristata, Pulsatrix perspicillata, Glaucidium hardyi, Ciccaba huhula, Ciccaba virgata) occurring in a area of “Terra-firme” forest in the central Amazon. From july 2001 to abril 2002, 18 transects of 8 km were surveyed at Reserva Florestal Adopho Ducke of the Instituto Nacional de Pesquisas da Amazônia (INPA) for the population census of 6 owls species. I compared plots of 50 x 50 m, placed where owls were detected. Within the 50 x50 m some components of the Forest were measured (canopy open, abundance of snags, abundance of trees, abundance of woody debris on the ground, the depth of leaf litter, altitude and the distance of closest water bodies) and compared with those in plots that owls are absent which were used as control. L. cristata and G. hardyi showed a pattern of spatial distribuition following the central platô wich divides the Reserve in the middle. O. watsonii, are distributed mainly in the southeast of the reserve while C. virgata, C. huhula and P. perspicillata showed low frequencies (2%). G. hardyi used areas closer to water bodies. Results of multiple regression analyses suggested that areas with a great abundance of snags were also significantly higher in density of L. cristata and O. watsonii. The variation of density of O. watsonii related to areas with a great abundance of trees and areas where the leaf litter was shallow were significantly. The different types of micro-basins, did not effect on the owl’s community composition, which one seemed to be preserved inside the reserve.A disponibilidade de comida, locais para nidificação e abrigo são características estruturais dos ambientes que são muito relevantes para sobrevivência das aves e cada uma delas pode influenciar de maneira diferente na estrutura de comunidades. Este estudo tem como objetivo principal estudar componentes da estrutura da floresta de descrição do habitat em relação a distribuição, o uso do habitat e a estrutura da comunidade de corujas (Otus watsonii, Lophostrix cristata, Pulsatrix perspicillata, Glaucidium hardyi, Ciccaba huhula, Ciccaba virgata) que ocorrem em floresta de Terra-firme de 10.000 ha, na reserva Ducke (Instituto Nacional de Pesquisas da Amazônia-INPA) Amazônia central. No período de julho de 2001 a abril de 2002, foram realizados os censos populacionais para as 6 espécies de corujas em 18 trilhas de 8 km, que compreendem o sistema de trilhas da Reserva Florestal Ducke. Foram demarcadas parcelas de 50x50 m em cada ponto de registro de coruja para medida dos componentes da estrutura da floresta e de descrição do habitat selecionados para este estudo (abertura do dossel, abundância de troncos mortos ainda em pé, abundância de árvores, abundância de troncos caídos no chão da floresta, profundidade do folhiço, altitude, distância do igarapé mais próximo) e parcelas de 50x50 m onde não ocorreram registros de corujas, para serem consideradas como controle para comparações com locais onde ocorreram registros de corujas. Lophostrix cristata e Glaucidium hardyi, apresentaram um padrão de distribuição acompanhando o platô central que divide a reserva. Otus watsonii, possui uma distribuição mais concentrada na parte sudeste enquanto que Ciccaba huhula, Ciccaba virgata, Pulsatrix perspicillata apresentaram baixa freqüência de ocorrência. Análises de regressão logística, realizadas com quatro espécies Lophostrix cristata e Glaucidium hardyi, Otus watsonii,e Ciccaba huhula. Houve um efeito positivo significativo da abundância de troncos mortos em pé na composição da comunidade de corujas, e na variação da densidade de Lophostrix cristata e de Otus watsonii. O uso do habitat por O. watsonii apresentou relações positivas e significativas com áreas com grande abundância de árvores e negativas e significativas com áreas com pouco folhiço. Glaucidium hardyi, parece usar mais freqüentemente áreas na floresta próximas a igarapés. Os diferentes tipos de micro- bacias não afetaram a composição da comunidade de corujas, a qual ainda parece bem estruturada e preservada dentro da reserva Ducke
From berry plant cropping to a cosmetic formula: sustainable upcycling of active ingredients
Due to the interest in berry fruit's antioxidant properties, its worldwide production has been increasing in the past two decades, as has its waste. Bioresidues produced by the agri-food industry are increasingly intrinsic to the world’s economy, and researchers are looking for new ways to enhance their use. Innovations are being developed to transform these residues into high-value raw materials with industrial applications, promoting the circular economy concept. Bioactive extracts from blueberry and raspberry aerial parts using green methodologies were obtained for this work. Different extraction techniques were considered and different conditions were tested to achieve optimal extraction conditions.info:eu-repo/semantics/publishedVersio
Paraquaternionic CR-submanifolds of paraquaternionic Kahler manifolds and semi-Riemannian submersions
In this paper we introduce paraquaternionic CR-submanifolds of almost
paraquaternionic hermitian manifolds and state some basic results on their
differential geometry. We also study a class of semi-Riemannian submersions
from paraquaternionic CR-submanifolds of paraquaternionic Kaehler manifolds.Comment: 19 page
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