Pollution-Aware Walking in 16 Countries:An Application of the Theory of Planned Behaviour (TPB)

Background: The current levels of air pollution in European countries reduces life expectancy by an average of 8 months. People who actively travel by walking have a higher level of exposure to air pollution than those who use motor vehicles or electric buses. Some routes have higher air pollution levels than others, but little is known about pollution-aware route choice and intentions to actively avoid walking near polluted roads. An improved understanding of how air pollution influences intentions to walk or avoid polluted routes can inform interventions to decrease exposure. The present investigation has three aims: (1) compare experiences walking near roads with high levels of air pollution across countries; (2) identify groups of countries based on perceptions of air quality; and (3) examine how pedestrians develop their intentions of avoiding pollution using the extended TPB (demographics, social norms, attitudes, perceived control, and perceived risk).Methods: A cross-sectional design was applied. Pedestrians were asked about their experiences walking near roads with high levels of air pollution. To identify groups of countries with different levels of air pollution, a cluster analysis was implemented based on the perceptions of air quality. Finally, regressions were used to predict pedestrians’ intentions to avoid polluted roads per country group using the extended TPB.Results: 6180 respondents (Age M(SD)= 29.4(14.2); Males= 39.2%) ranging from 12.6% from Russia to 2.2% from Finland completed the questionnaire. The proportion of participants who reported never walking near air polluted roads was 12.4% (from 3% in Brazil to 54% in Japan). Seven groups of countries were identified using perceptions of air quality: G1(Japan, Mexico, Colombia, Turkey, Malaysia & Brazil), G2(Spain, Romania & Czechia), G3(Chile, Russia & Peru), G4(China), G5(Australia), G6(Finland), and G7(Portugal). Participants in China (G4) and Australia (G5) reported the worst and best air quality respectively. Across all countries, intentions to avoid polluted roads were associated with perceptions of risk. TPB-psychosocial factors such as social norms and perceived behavioural control also influenced intention in most groups. Favourable TPB-beliefs and low perceived risk increase intentions to avoid polluted routes.Conclusions: The willingness of pedestrians to walk on or near roads with high levels of air pollution differs significantly among countries in this study. Countries can be grouped based on their perceived air quality. Perceived risk was the only common predictor of intention to avoid polluted routes across the different groups of countries

Alcohol-impaired Walking in 16 Countries:A Theory-Based Investigation

Alcohol is a global risk factor for road trauma. Although drink driving has received most of the scholarly attention, there is growing evidence of the risks of alcohol-impaired walking. Alcohol-impaired pedestrians are over-represented in fatal crashes compared to non-impaired pedestrians. Additionally, empirical evidence shows that alcohol intoxication impairs road-crossing judgements. Besides some limited early research, much is unknown about the global prevalence and determinants of alcohol-impaired walking. Understanding alcohol-impaired walking will support health promotion initiatives and injury prevention. The present investigation has three aims: (1) compare the prevalence of alcohol-impaired walking across countries; (2) identify international groups of pedestrians based on psychosocial factors (i.e., Theory of Planned Behaviour (TPB) and perceptions of risk); and (3) investigate how segments of pedestrians form their intention for alcohol-impaired walking using the extended TPB (i.e. subjective norm, attitudes, perceived control, and perceived risk). A cross-sectional design was applied. The target behaviour question was “have you been a pedestrian when your thinking or physical ability (balance/strength) is affected by alcohol?” to ensure comparability across countries. Cluster analysis based on the extended TPB was used to identify groups of countries. Finally, regressions were used to predict pedestrians’ intentions per group. A total of 6,166 respondents (Age M(SD) = 29.4 (14.2); Males = 39.2%) completed the questionnaire, ranging from 12.6% from Russia to 2.2% from Finland. The proportion of participants who reported never engaging in alcohol-impaired walking in the last three months ranged from 30.1% (Spain) to 83.1% (Turkey). Four groups of countries were identified: group-1 (Czech Republic, Spain, and Australia), group-2 (Russia and Finland), group-3 (Japan), and group-4 (final ten countries including Colombia, China, and Romania). Pedestrian intentions to engage in alcohol- impaired walking are predicted by perceptions of risk and TPB-psychosocial factors in group-1 and group-4. Favourable TPB-beliefs and low perceived risk increased alcohol-impaired walking intentions. Conversely, subjective norms were not significant in group-2 and only perceived risk predicted intention in group-3. The willingness of pedestrians to walk when alcohol-impaired differs significantly across the countries in this study. Perceived risk was the only common predictor among the 16 countries.</p

Estudo do incremento da produtividade na soldadura TIG de aços inoxidáveis austeníticos

Tese de doutoramento em Engenharia Mecânica (Tecnologia de Produção) apresentada à Fac. de Ciências e Tecnologia da Univ. de CoimbraO Processo de soldadura TIG (Tungsten Inert Gas) tem sido usado com assinalável sucesso na soldadura de aços inoxidáveis e ligas de alumínio, desde meados do século XX. Esse sucesso deve-se ao elevado nível de qualidade das soldaduras produzidas contudo o processo é lento e caro, sendo aplicável apenas à união de elementos finos. Pensou-se que a introdução da soldadura por plasma e da soldadura laser resolveria este problema de produtividade. Nos últimos anos verificou-se que estes processos são muito sensíveis à preparação de junta o que dirigiu de novo a atenção da investigação para o processo TIG. Este trabalho teve por objectivo estudar técnicas com o fim aumentar a produtividade deste processo, verificando em simultâneo se esses métodos produziam algum prejuízo em termos de microestrutura ou comportamento das soldaduras à corrosão. As soldaduras foram realizadas em cinco aços inoxidáveis austeníticos, do tipo AISI 304 e AISI 316, com teor em enxofre a variar entre 10 ppm e 80 ppm, utilizando uma gama de intensidade de corrente entre 100 e 300 A. Foi estudado o processo de soldadura convencional, a utilização de arco duplo em série e a aplicação de fluxos activantes nas chapas, vulgarmente designado processo A-TIG. Verificou-se que é possível obter aumentos de penetração que podem atingir os 100% com a utilização de fluxos à base de óxido de titânio ou de alumina. A realização da soldadura reduz a resistência à corrosão do aço devido às alterações localizadas na estrutura superficial. Contudo, a utilização do fluxo à base de óxido de titânio não induz uma diminuição adicional significativa dessa resistência à corrosã