11 research outputs found

    Three-way catalytic converter modeling as a modern engineering design tool

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    The competition to deliver ultra low emitting vehicles at a reasonable cost is driving the automotive industry to invest significant manpower and test lab resources in the design optimization of increasingly complex exhaust aftertreatment systems. Optimization can no longer be based on traditional approaches, which are intensive in hardware use and lab testing. This paper discusses the extents and limitations of applicability of state-of-the-art mathematical models of catalytic converter performance. In-house software from the authors' lab, already in use during the last decade in design optimization studies, updated with recent, important model improvements, is employed as a reference in this discussion. Emphasis is on the engineering methodology of the computational tools and their application, which covers quality assurance of input data, advanced parameter estimation procedures, and a suggested performance measure that drives the parameter estimation code to optimum results and also allows a less subjective assessment of model prediction accuracy. Extensive comparisons between measured and computed instantaneous emissions over full cycles are presented, aiming to give a good picture of the capabilities of state of the art engineering models of automotive catalytic converter systems

    Experimental investigation of the role of soot volatile organic fraction in the regeneration of diesel filters

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    This paper involves an experimental investigation of the role of the volatile organic fraction (VOF) adsorbed on the diesel particulate, in the initiation of regeneration of a SiC diesel filter installed on a modern diesel engine, run on catalytic additive-doped fuel. VOF adsorption-desorption and oxidation behaviour is mainly determined by performing a thermogravimetric analysis (TGA) of samples collected directly from a SiC filter installed on the engine running under low- and medium-speed and low- and medium-load conditions, as more representative of city driving. Based on the TGA analysis results, the percentage VOF content in soot was calculated and mapped as a function of engine speed and load in the range of investigation. The effect of adsorbed hydrocarbons on the regeneration behaviour was assessed by comparing regeneration experiments with the stepwise load increase for a filter loaded with soot at different VOF concentration levels. The appearance of a number of incidents of stochastic regeneration behaviour during loading at low exhaust temperatures with a relative high VOF content was observed and discussed. An effort was made to correlate regeneration rate with the VOF content in soot and the prevailing engine operation point during loading. This work aims at better understanding of diesel filter behaviour with modern diesel engines and also aims to support improved modelling of fuel-additive assisted regeneration by use of fuel additives at low temperatures (150-400degreesC)

    Video Game Therapy for Emotional Regulation and Impulsivity Control in a Series of Treated Cases with Bulimia Nervosa

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    Although standard psychological treatments have been successful in treating several core features in eating disorders (ED), other characteristics such as emotional regulation or impulsivity appear to be more resistant to change. There is a growing body of evidence to support the efficacy of cognitive remediation for cognitive and emotional difficulties in ED. Playmancer/ Islands is a video game (VG) designed to specifically treat mental disorders, characterized by problems in impulse control. The objective of the game is to increase self-control over emotions, decision making and behaviours. The aim of this study is to describe the results from a consecutive series of nine bulimia nervosa patients who were treated with the VG in addition to cognitive behaviour therapy (CBT). The outcomes included clinical and psychopathological questionnaires, and physiological measures were obtained during the VG. Emotional regulation improved, heart rate variability increased, and respiratory rate and impulsivity measures reduced after the treatment. These findings suggest that VG training may enhance treatment for ED. Copyright © 2013 John Wiley & Sons, Ltd and Eating Disorders Association. Copyright © 2013 John Wiley & Sons, Ltd and Eating Disorders Association

    Interoperability in ServiceBased Communities

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    Abstract. Interoperability is a multifaceted problem caused by issues surpassing those of technological incompatibilities. The real interoperability challenges are stemming from various sources, such as organisational incompatibilities buried deeply into the structures of collaborating enterprises, architectural mismatches and defective assumptions about business application behaviour, or from the inherent properties of business collaboration models. To achieve interoperability in enterprise computing environments, the aspects of interoperability must be identified and their properties analysed. This paper studies interoperability issues in enterprise computing environments. Enterprise computing environments under analysis are based on Service Oriented Computing paradigm and enhanced with necessary infrastructure facilities. Several classes of causes for interoperability problems are identified and the mechanisms for overcoming the problems in these classes are briefly discussed.

    Video games as a complementary therapy tool in mental disorders: PlayMancer, a European multicentre study

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    Background: Previous review studies have suggested that computer games can serve as an alternative or additional form of treatment in several areas (schizophrenia, asthma or motor rehabilitation). Although several naturalistic studies have been conducted showing the usefulness of serious video games in the treatment of some abnormal behaviours, there is a lack of serious games specially designed for treating mental disorders. Aim: The purpose of our project was to develop and evaluate a serious video game designed to remediate attitudinal, behavioural and emotional processes of patients with impulse-related disorders. Method and results: The video game was created and developed within the European research project PlayMancer. It aims to prove potential capacity to change underlying attitudinal, behavioural and emotional processes of patients with impulse-related disorders. New interaction modes were provided by newly developed components, such as emotion recognition from speech, face and physiological reactions, while specific impulsive reactions were elicited. The video game uses biofeedback for helping patients to learn relaxation skills, acquire better self-control strategies and develop new emotional regulation strategies. In this article, we present a description of the video game used, rationale, user requirements, usability and preliminary data, in several mental disorders
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