A Decision-Tree-Based Approach to Smoke Spike Detection in a Heavy-Duty Diesel Engine

Smoke spikes occurring during transient engine operation have detrimental health effects and increase fuel consumption by requiring more frequent regeneration of the diesel particulate filter. This paper proposes a decision tree approach to real-time detection of smoke spikes for control and on-board diagnostics purposes. A contemporary, electronically controlled heavy-duty diesel engine was used to investigate the deficiencies of smoke control based on the fuel-to-oxygen-ratio limit. With the aid of transient and steady state data analysis and empirical as well as dimensional modeling, it was shown that the fuel-to-oxygen ratio was not estimated correctly during the turbocharger lag period. This inaccuracy was attributed to the large manifold pressure ratios and low exhaust gas recirculation flows recorded during the turbocharger lag period, which meant that engine control module correlations for the exhaust gas recirculation flow and the volumetric efficiency had to be extrapolated. The engine control module correlations were based on steady state data and it was shown that, unless the turbocharger efficiency is artificially reduced, the large manifold pressure ratios observed during the turbocharger lag period cannot be achieved at steady state. Additionally, the cylinder-to-cylinder variation during this period were shown to be sufficiently significant to make the average fuel-to-oxygen ratio a poor predictor of the transient smoke emissions. The steady state data also showed higher smoke emissions with higher exhaust gas recirculation fractions at constant fuel-to-oxygen-ratio levels. This suggests that, even if the fuel-to-oxygen ratios were to be estimated accurately for each cylinder, they would still be ineffective as smoke limiters. A decision tree trained on snap throttle data and pruned with engineering knowledge was able to use the inaccurate engine control module estimates of the fuel-to-oxygen ratio together with information on the engine control module estimate of the exhaust gas recirculation fraction, the engine speed, and the manifold pressure ratio to predict 94% of all spikes occurring over the Federal Test Procedure cycle. The advantages of this non-parametric approach over other commonly used parametric empirical methods such as regression were described. An application of accurate smoke spike detection in which the injection pressure is increased at points with a high opacity to reduce the cumulative particulate matter emissions substantially with a minimum increase in the cumulative nitrogrn oxide emissions was illustrated with dimensional and empirical modeling.

Drinking, Family Relations and Authority in Early Modern Germany

The ideal of orderly family life in early modern Germany did not exclude drinking. In fact, drinks shared at the family table were closely tied to early modern notions of the marital bond and were also a necessary component of normal work relations. Drinking became a problem only when it threatened the stability of the household. The amount of alcohol involved in such cases might be as little as one drink if the circumstances were unsuitable. On the other hand, drinking that would by our standards be viewed as excessive or chronic could be considered acceptable . Even during and immediately after the period of Reformation, when polemical and prescriptive literature addressing the household was dominated by the problem of sin, drunkenness was rarely treated as a spiritual issues. The primary concern of both authorities and populace was not to protect the health or the rights of individuals but to protect the sanctity of the household and the stability of the community.

Public Drinking in the Early Modern World: Voices from the Tavern, 1500-1800

Until recently the role of the public drinking house has been approached from elitist, folkloric and anecdotal perspectives. The work of a new generation of social historians, however, has raised the tavern’s profile in the academic consciousness and confirmed its position within the mainstream of social and cultural history. It is now recognized that an understanding of the centrality of public drinking to the development of both elite and popular culture is vital to studies of social behaviour. The study of taverns has also been at the forefront of emerging interest in the history of consumption and material culture, and has contributed to a richer understanding of economic history. Constructions of gender and identity are also visible through research into the patterns of behaviour and discourse in and around the public house. This four-volume reset edition presents a wide-ranging collection of primary sources which uncover the language and behaviour of local and state authorities, of peasants and town-dwellers, and of drinking companions and irate wives. The documents are translated and set in their social and historical context, providing a multidisciplinary collection that will be of great importance to scholars of all areas of social and cultural history of the early modern period. The vast majority of this material is published here for the first time, ensuring that the collection will open up new avenues of research. Volume 1 draws heavily from the Parisian police archives and includes inspectors’ reports, complaints by the general public and details of court cases to build a picture of drinking in early modern France. Volumes 2 and 3 address public drinking in the Holy Roman Empire through a variety of chronicles, civic ordinances, court records, travel reports and surveys of public houses. Volume 4 locates taverns within a broader analysis of America’s public houses, drawing on visual material as well as journal entries, business reports and newspaper articles. Each volume is accompanied by editorial introductions and is annotated to provide readers with a high-quality resource of scholarly material.