Search results for "exhaust"
showing 10 items of 138 documents
Transition Metal Compound Oxide Catalysts for Lowering the Light Off-Temperature of Particles from Diesel Exhaust
1993
Publisher Summary It has been realized that particle emissions from diesel engines are a severe environmental problem, which is difficult to solve by engine modifications alone. Even if the combustion occurs in a high excess of air, appreciable amounts of soot particles are found. Cracking processes, dehydrogenation, and polymerization play an important role in the formation of soot. To reduce soot fraction, several methods have been developed in the past, but most of them have fundamental disadvantages. Thus, a new procedure based on the catalytic burning of the soot in the exhaust gas is becoming important. This chapter describes the effect of several compound oxides. Further investigatio…
Psychosocial work stressors and well-being: self-esteem and optimism as moderators in a one-year longitudinal sample
2003
The purpose of the present follow-up study was to investigate the roles of self-esteem and optimism in the relationship between psychosocial work stressors and well-being for a sample of Finnish employees (n=457). The data were obtained by means of questionnaires which were completed twice, in 1999 and 2000. The results of the moderated hierarchical regression analyses revealed that low levels of self-esteem and optimism had a direct negative effect on emotional exhaustion and mental distress among men employees. Furthermore, self-esteem moderated the relationships between poor organizational climate and emotional exhaustion and mental distress among male employees. Among female employees o…
Energy management strategy to reduce pollutant emissions during the catalyst light-off of parallel hybrid vehicles
2020
Abstract The transportation sector is a major contributor to both air pollution and greenhouse gas emissions. Hybrid electric vehicles can reduce fuel consumption and CO2 emissions by optimizing the energy management of the powertrain. The purpose of this study is to examine the trade-off between regulated pollutant emissions and hybrid powertrain efficiency. The thermal dynamics of the three-way catalyst are taken into account in order to optimize the light-off. Experimental campaigns are conducted on a spark-ignition engine to introduce simplified models for emissions, exhaust gas temperature, catalyst heat transfers and efficiency. These models are used to determine the optimal distribut…
Associations between observed patterns of classroom interactions and teacher wellbeing in lower secondary school
2019
Classroom observations and teacher self-reports were used to examine the relationships between patterns of teacherestudent interactions and the wellbeing of Norwegian lower secondary school teachers. Latent profile analysis identified four subgroups. Teacherestudent interactions and the teachers' wellbeing were inter-related in that teachers who were observed to be high in all the interaction domains (Emotional Support, Classroom Organization, and Instructional Support) perceived themselves as having high job satisfaction. The results showed that improving teachers’ wellbeing has the potential to improve teacherestudent interactions and vice versa. The study also discusses the use of classr…
Exhaust Pipe Design Method for the Optimization of the Scavenging Process
1985
Conception des tuyauteries d'echappement en vue d'optimiser le balayage dans un moteur deux temps
FE Calculation Methodology for the Thermodynamic Fatigue Analysis of an Engine Component
2006
Thermo mechanical fatigue problem is treated to define an analysis methodology permitting the strength evaluation by reliability viewpoint. The main difficulty is the lack of both theoretical and experimental information; consequently the problem is treated verifying continually the validity and the limits of the developing solution method. The main task of the activity described in this paper was the development of a numerical methodology, based on FE analyses, for the evaluation of the structural behavior of engine components subjected to thermo mechanical fatigue phenomena. The chosen application was the exhaust manifold of an IC engine; FE analyses were executed following the standard m…
Heat stroke risk for open-water swimmers during long-distance events.
2013
Open-water swimming is a rapidly growing sport discipline worldwide, and clinical problems associated with long-distance swimming are now better recognized and managed more effectively. The most prevalent medical risk associated with an open-water swimming event is hypothermia; therefore, the Federation Internationale De Natation (FINA) has instituted 2 rules to reduce this occurrence related to the minimum water temperature and the time taken to complete the race. Another medical risk that is relevant to open-water swimmers is heat stroke, a condition that can easily go unnoticed. The purpose of this review is to shed light on this physiological phenomenon by examining the physiological re…
Corrigendum to “Personal protective equipment and intensive care unit healthcare worker safety in the COVID-19 Era (PPE-SAFE): An international surve…
2021
The authors regret errors were present in the published article. Counts of some of the adverse events were erroneous. Changes to the text include. Last sentence of the abstract should read. Adverse effects of PPE included heat (1266, 51%), thirst (1174, 47%), pressure areas (1088, 44%), headaches (696, 28%), Inability to use the bathroom (661, 27%) and extreme exhaustion (492, 20%). All but pressure areas were associated with longer shift durations. Last sentence of the results section of the manuscript should read. All but pressure areas were associated with longer duration of shifts wearing PPE (Table 4). Table 1 the total number of community/urban type of hospital should read 740 instead…
A Fair Share of Work: Is Fairness of Task Distribution a Mediator Between Transformational Leadership and Follower Emotional Exhaustion?
2019
Drawing on social resource theory and the norm of equity, this research proposes fairness of task distribution as a mediating mechanism of the well-established relationship between transformational leadership and followers’ well-being, conceptualizing the latter as low emotional exhaustion. Using data from 479 German employees in a three-wave longitudinal study, we found transformational leadership to be related to fair task distribution over time. The perceived fairness of task distribution mediated the relationship between transformational leadership and follower emotional exhaustion (structural equation modeling) when excluding stabilities. Our results also show a reverse causation effec…