3,852 research outputs found
Coal and fuel burning effects on the atmosphere as mediated by the atmospheric electric field and galactic cosmic rays flux
Abstract: Emissions into the atmosphere of Greenhouse Gases (GHGs) and
particulate matter resulting from fossil fuel burning are considered to be the
main anthropogenic forcing on the global climate. We show here that
the external cyclic influences of cosmic origin that modulate the earth’s climate
may either reinforce or mitigate the ‘local’ terrestrial forcings. Among the
external influences is cosmic radiation, whose intensity shows a cyclic
variation of 11 years, accompanying the 11-year cycle of solar activity. We put
forward a mechanism to explain how the emission of particulate matter into the
atmosphere might influence global lightning activity. With respect to global
lightning activity, we show why, during the 11-year cycle, the influence of an
increase in particulate matter concentration in the atmosphere may be
negligible in some years, while it will be reinforced in other years, depending
on the place of the years in the cycle. We also remark that the effect on global
warming of fossil fuel burning is also modulated by the cosmic ray flux, whose
influence is mediated by the variation that it promotes on the cloud cover
Influences of cosmic radiation, artificial radioactivity and aerosol concentration upon the fair-weather atmospheric electric field in Lisbon (1955–1991)
The atmospheric electric field is influenced by cosmic radiation, radioactivity and aerosols. In this work we investigate the existence of: (i) correlations between relative anomalies of annual values of atmospheric electric field and cosmic radiation intensity, artificial radioactivity and aerosol concentration; (ii) seasonal correlations between relative anomalies of the atmospheric electric field and cosmic radiation intensity. We used data of the electric field strength recorded at the Portela meteorological station (Lisbon) in the period 1955–1991. We found statistically significant inverse correlations between atmospheric electric field and cosmic radiation in the period 1967–1991. We also found that the influence of cosmic radiation on the atmospheric electric field is strong in wintertime and very weak in summertime. The GCR–CN–CCN–Cloud Hypothesis and the wintertime reduced boundary layer convection are analyzed as possible explanations for this difference
Schumpeter’s (1934) influence on entrepreneurship (and management) research
Entrepreneurship research has flourished since de 1980s, following the institutional development that created schools and courses, research centers and dedicated journals. This paper examines the impact of Joseph Schumpeter, one of the main “knowledge producers” whose concepts and ideas on the entrepreneur, entrepreneurship and innovation have shaped the discipline and much of the research on entrepreneurship, and has influenced the thought on other areas of management. Methodologically, we conducted a bibliometric study of the articles published in 16 high stature international journals, over a period of 30 years, between 1981 and 2010. On a sample of 412 articles citing Schumpeter, we analyzed and mapped citations, co-citations and research themes. We further establish distinctions between entrepreneurship and management research. This study presents a manner to examine the influence of a scholar, and a set of conceptualizations he has introduced, on a discipline. Schumpeter has had an imprint in the multidisciplinary and wealth of research themes that entrepreneurship scholars have delved upon but also in other management disciplines, where his perspectives on entrepreneurship, the entrepreneur and innovation have contributed to much of the research conducted to date. Although entrepreneurship has remained largely multidisciplinary and drawing from the main management theories there is a growing body of entrepreneurship-specific literature.info:eu-repo/semantics/publishedVersio
Simulations in virtual reality: assessment of firefighters' decision-making competence
This study focuses on the use of virtual reality simulations for the training of portuguese firefighters in emergency operations management and the assessment of decision-making competence. The research was carried out through the action-research method. In the first cycle a pilot training course was carried out in a group of eight trainers from the Portuguese National Fire Service School, in which data were collected on the performance of trainees and in the evaluation of training. In the last step, corrections and improvements to the training course were identified. In the second cycle of action-research the steps were repeated with the formal implementation of the training course for eight fire officers of several fire brigades in the country. Every trainee played the role of incident commander in two different training scenarios and their performance was assessed at both times using a common evaluation tool. The evaluation of the impact of the changes introduced in the second cycle was carried out through a comparative analysis of the learning assessments, the evaluations of the trainees of the two groups and the evaluation of the team of trainers. The results of the trainees' performance and the training evaluation allow to conclude that the training course promoted the development of decision-making competence in the management of emergency operations using virtual reality simulations.info:eu-repo/semantics/publishedVersio
Quality-of-Life Perception among Young Residents and Visitors: The Impact of COVID-19
This research intends to measure the quality of life (QoL) perception, from the perspective
of residents and tourists towards Coimbra, a city with an important World Heritage Site, as classified
by UNESCO. In these times, preserving tangible and intangible heritage is so important for future
memories. Identifying the QoL perceptions through the eyes of residents and tourists allows the
improvement of the community well-being of the destination for both stakeholders. Starting from
this assumption, this study aims to: (i) measure the tourists’ and residents’ perceptions on quality
of life (QoL); (ii) analyze the impact of the COVID-19 pandemic on QoL perceptions, both from the
tourists’ and residents’ perspective. To achieve these objectives, a questionnaire was disseminated to
residents and tourists in two different phases, before and during the COVID-19 pandemic. Results
show that in general, residents and tourists exhibited, in both periods, medium and high perceptions
of QoL, with an exception made for the Urban Issues domain that decreased even more during the
pandemic. Furthermore, the results show, for residents and tourists, that the perception of Urban
Issues, Way of Life, Community Pride and Awareness, Economic Strength, and Recreation Amenities impact
significantly and positively their Community Well-Being perception. New paths for academics and for
practitioners are presented at the end, as well as limitations and evidence for future research.info:eu-repo/semantics/publishedVersio
Hechos, Mitos y Creencias sobre la Electricidad Atmosférica desde una Perspectiva Didáctica
Es indiscutible hoy el valor social de la educación en ciencias. Los fenómenos naturales observados desde temprano por los alumnos precisan explicaciones de naturaleza científica. Entre éstes está la electricidad atmosférica que, no obstante un fenómeno natural relativamente bien explicado en nuestros días, frecuentemente aparece asociado a ciertos mitos, temores y fantasmas, muchas veces sin ningún fundamento. En este artículo, se presentan algunos de los resultados de un estudio empírico que fue realizado precisamente sobre este tema, los intervenientes siendo alumnos del 8.º ano de enseñanza de dos escuelas del Alentejo, dos profesoras de Ciencias Físico-Químicas más los investigadores. En este estudio, inspirado en la etnografía, se empezó con la elaboración, por los alumnos, de un trabajo de averiguación sobre los hechos reales, mitos y creencias referentes a la electricidad con el propósito de, después de haber debatido en la aula sobre algunas de las limitaciones de estes elementos del conocimiento común, confrontar aquéllos con las explicaciones científicas correspondientes, planteadas a través de pequeñas anécdotas didácticas elaboradas por los investigadores
Sentidos de portunhol: defesa e condenação
Este trabalho, fruto de nosso trabalho de mestrado, apresenta uma análise da palavra língua a partir de um texto retirado de um blog assinado por Pedro Kaul um internauta, que contesta a atitude do então Ministro da Cultura, Gilberto Gil, de defender o uso do portunhol. O texto do ministro é apresentado por Kaul por meio de construções do discurso relatado intercalado com trechos, marcado pelas aspas, em discurso direto. A partir dos pressupostos teóricos e metodológicos da Semântica do Acontecimento, em um trabalho analítico a partir da constituição dos domínios semânticos de determinação da palavra língua estudaremos o sentido desta palavra e o funcionamento destes sentidos na determinação de portunhol. Veremos que há dois sentidos de língua postos neste texto: língua enquanto norma e língua enquanto prática daqueles que a falam. Desta forma veremos que portunhol significa por um cruzamento destes dois sentidos que produzem um deslizamento de sentidos que ora legitimam portunhol, ora o deslegitimam enquanto língua
Adaptation of the generic DISABKIDS® module for Brazilian children and adolescents with chronic disorders
OBJECTIVES: to describe the process of cultural adaptation to Brazil Generic Module DISABKIDS for Chronic Conditions (DCGM-37), a generic instrument for measuring the quality of life of children and adolescents with chronic conditions. METHODS: a cross-cutting methodological study was carried out in pediatric outpatients clinics in Brazil, covering 118 children/adolescents with asthma or diabetes and their parents or carers. Translation, back-translation and cultural adaptation were carried out to obtain conceptual and semantic equivalence at the level of individual items.Equivalence was measured statistically by describing the initial psychometric properties, using validity and reliability criteria. RESULTS: most of the items were considered relevant and 14 of them were modified following the semantic validation phase. Values for Cronbach's alpha were α=0.92 and α=0.93, for the version for children and adolescents and the version for parents and carers, respectively. Analysis of correlations between items and dimensions revealed a satisfactory degree of convergent and discriminant validity. CONCLUSIONS: the initial phase indicates that DISABKIDS module is a valid and reliable tool for measuring quality of life in a Brazilian context.OBJETIVOS: descrever o processo de adaptação cultural para o Brasil do Módulo Genérico DISABKIDS para Condicões Crônicas (DCGM-37), um instrumento genérico para mensuração da qualidade de vida de crianças e adolescentes com condições crônicas. MÉTODOS: estudo metodológico, transversal, conduzido em ambulatórios pediátricos brasileiros, incluindo 118 crianças/adolescentes com asma ou diabetes e seus pais/cuidadores. Os processos de tradução-retrotradução e adaptação cultural foram realizados visando a obter equivalência conceitual e semântica em nível de itens. A equivalência de medida foi avaliada por análise estatística, realizada para descrição das propriedades psicométricas iniciais, segundo os critérios de validade e confiabilidade. RESULTADOS: a maioria dos itens foi considerada relevante e 14 deles foram modificados após a fase de validação semântica. Valores para a estatística alfa de Cronbach foram α=0,92 e α=0,93, para a versão crianças/adolescentes e pais/cuidadores respectivamente. A análise das correlações entre itens e dimensões mostrou validade convergente e discriminante satisfatórias. CONCLUSÕES: a fase inicial indica que o instrumento deverá constituir ferramenta válida e confiável para mensuração da qualidade de vida na realidade brasileira.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Federal de São Paulo (UNIFESP)Universidade Federal do Rio Grande do Sul Departamento de Odontologia Preventiva e SocialUniversidade de São Paulo Escola de Enfermagem de Ribeirão PretoUniversitätsklinikum Hamburg-Eppendorf Instituto e Policlínica de Medicina PsicológicaUNIFESPSciEL
PORTUÑOL X SPANGLISH: UM ESTUDO DOS DOMÍNIOS SEMÂNTICOS DE DETERMINAÇÃO NO ESPAÇO ENUNCIATIVO DA INTERNET
Este trabalho tem como objetivo realizar uma análise dos sentidos de portuñol/portunhol e spanglish/ espaninglês no espaço enunciativo da Internet, respondendo os seguintes questionamentos: o que determina, neste espaço enunciativo estas práticas enquanto práticas (des) legitimadas? Quais são os sentidos e relações que circulam neste espaço, funcionando na determinação de portunhol e espaninglês? Utilizando-nos dos aparatos teóricos e metodológicos da Semântica do Acontecimento, em diálogo com a Análise do Discurso francesa, realizaremos um estudo sobre os domínios semânticos de determinação, (Guimarães, 2007) destas palavras, considerando o funcionamento da Internet a partir do conceito de espaço de enunciação
SSM: A Semantic Metasearch Platform for Scientific Data retrieval
Scientific research in all fields has advanced in complexity and in the amount of data generated. The heterogeneity of data repositories, data meaning and their metadata standards makes this problem even more significant. In spite of several proposals to find and retrieve research data from public repositories, there is still need for more comprehensive retrieval solutions. In this article, we specify and develop a mechanism to search for scientific data that takes advantage of metadata records and semantic methods. We present the conception of our architecture and how we have implemented it in a use case in the agriculture domain
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