1,848 research outputs found

    Hydrological impacts of floodplain restoration: a case study of the River Cherwell, UK

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    International audienceThis paper investigates the impacts on floods of hypothetical changes to river channel geometry by construction or removal of embankments to prevent water spreading onto the floodplain at high flows. A numerical model is applied to the River Cherwell between Oxford and Banbury to simulate changes to flood hydrographs. Embanking the river increases the peak flows downstream by 50-150%. Restoring the river channel through the floodplain to pre-engineered dimensions reduces peak flow by around 10-15% and increases peak water levels within the floodplain by 0.5-1.6 m. These results suggest that floodplain rehabilitation, in terms of embankment removal or returning the channel to pre-engineered dimensions, can be a valuable part of the flood management strategy of a catchment. Both measures lead to increased inundation of the floodplain, which can be positive for ecological restoration. Keywords: floodplains, hydrological impacts, rehabilitation, flood frequenc

    A mathematical model for the sequestering of chemical contaminants by magnetic particles

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    A mathematical model is developed and implemented to characterize the pickup of various liquid chemical contaminants by polyethylene-coated magnetic particles. The model and its associated experimental and analytical protocols were applied to a wide range of liquid chemicals in order to gain insights into the physical basis for the pickup phenomenon. The characteristics of the pickup isotherms range between “ideal” and “nonideal” behaviors that are reflected in the mathematical model by a single parameter, �0, where �0=1 corresponds to ideal behavior and �0�1 corresponds to a departure from idealized behavior that is directly quantified by the magnitude of �0. The parameter �0 is also related to the efficiency of pickup, and since most isotherms observed in the study deviate from ideality, the high efficiency of pickup observed in these systems has been attributed in part to this deviation. The proposed model and its associated experimental and analytical protocols demonstrate great potential for the systematic evaluation of the uptake of chemical contaminants using magnetic particle technology

    Characterising the Performance of Selected Electrical Machine Insulation Systems

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    Criminal narrative experience: relating emotions to offence narrative roles during crime commission

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    A neglected area of research within criminality has been that of the experience of the offence for the offender. The present study investigates the emotions and narrative roles that are experienced by an offender while committing a broad range of crimes and proposes a model of Criminal Narrative Experience (CNE). Hypotheses were derived from the Circumplex of Emotions (Russell, 1997), Frye (1957), Narrative Theory (McAdams, 1988) and its link with Investigative Psychology (Canter, 1994). The analysis was based on 120 cases. Convicted for a variety of crimes, incarcerated criminals were interviewed and the data were subjected to Smallest Space Analysis (SSA). Four themes of Criminal Narrative Experience (CNE) were identified: Elated Hero, Calm Professional, Distressed Revenger and Depressed Victim in line with the recent theoretical framework posited for Narrative Offence Roles (Youngs & Canter, 2012). The theoretical implications for understanding crime on the basis of the Criminal Narrative Experience (CNE) as well as practical implications are discussed
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