142 research outputs found

    Analysis of coil slumping

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    Steel strip is usually stored as a coil, which will slump to some degree after the removal of the mandrel. More often than not, the amount of slumping is so minor that it is assumed not to have occurred. Occasionally, the amount, though minor, is sufficient to compromise the integrity of the cylindrical bore which compromises subsequent handling of the coil. In extreme situations, the slumping progresses to a complete collapse of the coil. Such a collapse is rare. It occurs when a coil cannot hold up its own mass and loses its circular cross-section. It is thought to be principally associated with the size and weight of the coil, inappropriate coiling tensions and/or poor re-coiler equipment design. Strip properties, especially inter-strip contact characteristics, have been demonstrated experimentally to be crucial determinants of whether or not coil collapse is likely to occur. The particular kind of slumping/collapse of interest to BlueScope Steel, who proposed this Study Group problem, is the minor slumping that compromises cylindrical bore integrity. It is referred to as coil slump. The Study Group was asked to investigate and model the phenomenon of coil slumping, and, if possible, to quantify the effect of critical parameters, especially coil mass, strip thickness and inter-strip friction. In particular, it was suggested that deliberations should aim to characterize the geometry of slumping and to predict the deformation profile at the innermost and outermost wraps. For BlueScope Steel, the long term objectives are: (1) the formulation of the governing equations for the stresses in a coil under self-weight, (2) the identification of analytical solutions and/or numerical schemes for the final coil shape after slumping, and (3) the formulation of exclusion rules-of-thumb which predict when a particular form of slump (oval or triangular) is likely to occur. The Study Group made some progress with (1), limited progress with (2) and most progress with (3). Though various computer programs were written to explore different force and energy balance scenarios, they only scratched the surface with regards to (2). Success with it is heavily dependent in substantial progress being made with (1). As explained in detail in the sequel, the Study Group’s deliberations resulted in an improved understanding of the coil slumping/collapse problem by identifying a number of specific issues that should be of direct assistance to BlueScope Steel’s future management of coil slumping/collapse. In particular, such issues included the need, from a modelling perspective, to draw a clear distinction between minor slumping and major slumping which can subsequently lead to collapse; the formulation of a heuristic hypothesis about the dynamics of coil slumping/collapse which can be compared with historical data and act act as a conceptualization guide for further investigations; the identification of a “tension-weight ratio” (R) as the relevant dimensionless group which represents an indicative rule-of-thumb which can be applied in practice; and proposed, on the basis of the hypothesis, an efficient procedure for recording collapse events and statistically identifying possible collapse situations

    A smart driving smartphone application : real-world effects on driving performance and glance behaviours

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    A smart driving Smartphone application – which offers real-time fuel efficiency and safety feedback to the driver in the vehicle – was evaluated in a real-world driving study. Forty participants drove an instrumented vehicle over a 50 minute mixed route driving scenario, with 15 being selected for video data analysis. Two conditions were adopted, one a control, the other with smart driving advice being presented to the driver. Key findings from the study showed a 4.1% improvement in fuel efficiency when using the smart driving system, and an almost 3-fold reduction in time spent travelling closer than 1.5 seconds to the vehicle in front. Glance behavior results showed that drivers spent an average of 4.3% of their time looking at the system, at an average of 0.43 seconds per glance, with no glances of greater than two seconds. In conclusion this study has shown that a smart driving system specifically developed and designed with the drivers’ information requirements in mind can lead to significant improvements in real-world driving behaviours, whilst limiting visual distraction, with the task being integrated into normal driving

    Usability of TeleFOT Nomadic and Aftermarket Devices [D1.8]

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    This deliverable reports on the Usability activities undertaken in TeleFOT mainly within WPs 4.8 and 4.10. These planned to support the Sub-Project 4 of TeleFOT in Evaluation and Assessment of nomadic devices within the national Field Operational Tests (FOTs). The key objective of WP4.8 in this regard is to provide measurable data that allows comparing usability and user experience of different driver assistance services whilst the key objective of WP4.10 is to identify and define the target and actual technical performance metrics for the Nomadic Devices (NDs) used. Two approaches are described in this Deliverable which have been utilised within TeleFOT for evaluating the usability of the nomadic and aftermarket devices tested within the TeleFOT FOTs. The first approach describes the feedback received from the TeleFOT participants with regard to their user experiences with the devices tested during the FOTs. To complement this information, each test site was asked to supply usability information specifically related to the time taken and the number of user interactions (aka button presses) to access certain functions within their ND. These included time and interactions to access the main menu and primary function, or adjust the volume, as well as to start up and shut down. The participants’ opinions on the design of the device, user interface, initial reactions and benefits to the NDs were then recorded as were ‘Other Issues’ which related to participants’ perceived usefulness, reliability and ease to interpret the information offered by the ND. This method allowed in-depth information to be captured surrounding issues which may have influenced the use of the ND during the FOT and/or common issues which arose. The second approach involved expert evaluations undertaken by HMI analysts working at the test-sites on a number of devices that were tested within TeleFOT. Not all of the devices that were tested within TeleFOT were subjected to expert evaluations. However, the procedure for such evaluations is described along with the results

    Glance behaviours when using an in-vehicle smart driving aid : a real-world, on-road driving study

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    In-vehicle information systems (IVIS) are commonplace in modern vehicles, from the initial satellite navigation and in-car infotainment systems, to the more recent driving related Smartphone applications. Investigating how drivers interact with such systems when driving is key to understanding what factors need to be considered in order to minimise distraction and workload issues while maintaining the benefits they provide. This study investigates the glance behaviours of drivers, assessed from video data, when using a smart driving Smartphone application (providing both eco-driving and safety feedback in real-time) in an on-road study over an extended period of time. Findings presented in this paper show that using the in-vehicle smart driving aid during real-world driving resulted in the drivers spending an average of 4.3% of their time looking at the system, at an average of 0.43 s per glance, with no glances of greater than 2 s, and accounting for 11.3% of the total glances made. This allocation of visual resource could be considered to be taken from ‘spare’ glances, defined by this study as to the road, but off-centre. Importantly glances to the mirrors, driving equipment and to the centre of the road did not reduce with the introduction of the IVIS in comparison to a control condition. In conclusion an ergonomically designed in-vehicle smart driving system providing feedback to the driver via an integrated and adaptive interface does not lead to visual distraction, with the task being integrated into normal driving

    Deriving on-road spatial vehicle emission profiles from chassis dynamometer experiments

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    A method has been derived for the identification of spatial emission hot-spots on vehicle road routes using chassis dynamometer data. The work presented here uses tailpipe-out carbon monoxide (CO) levels to demonstrate the application of the method. The approach is used to analyse critically methods used by legislators that derive road-side emission levels from the vehicle emission inventory and legislative emission levels. The work presented in this paper demonstrates that the generic approach using vehicle speed, gear change patterns, spatial geographical data, and route geometric information is sufficient for the identification of the location of emission hot-spots in any journey route of interest

    Real-world performance of catalytic converters

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    This paper investigates experimentally the performance of a three-way catalytic (TWC) converter for real-world passenger car driving in the United Kingdom. A systematic approach is followed for the analysis using a Euro-IV vehicle coupled with a TWC converter. The analysis shows that the real-world performance of TWC converters is significantly different from the performance established on legislative test cycles. It is identified that a light-duty passenger vehicle certified for Euro-IV emissions reaches the gross polluting threshold limits during real-world driving conditions. This result is shown to have implications for overall emission levels and the use of remote emissions sensing and on-board diagnostics (OBD) systems

    Homologous and heterologous desensitization of guanylyl cyclase-B signaling in GH3 somatolactotropes

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    The guanylyl cyclases, GC-A and GC-B, are selective receptors for atrial and C-type natriuretic peptides (ANP and CNP, respectively). In the anterior pituitary, CNP and GC-B are major regulators of cGMP production in gonadotropes and yet mouse models of disrupted CNP and GC-B indicate a potential role in growth hormone secretion. In the current study, we investigate the molecular and pharmacological properties of the CNP/GC-B system in somatotrope lineage cells. Primary rat pituitary and GH3 somatolactotropes expressed functional GC-A and GC-B receptors that had similar EC50 properties in terms of cGMP production. Interestingly, GC-B signaling underwent rapid homologous desensitization in a protein phosphatase 2A (PP2A)-dependent manner. Chronic exposure to either CNP or ANP caused a significant down-regulation of both GC-A- and GC-B-dependent cGMP accumulation in a ligand-specific manner. However, this down-regulation was not accompanied by alterations in the sub-cellular localization of these receptors. Heterologous desensitization of GC-B signaling occurred in GH3 cells following exposure to either sphingosine-1-phosphate or thyrotrophin-releasing hormone (TRH). This heterologous desensitization was protein kinase C (PKC)-dependent, as pre-treatment with GF109203X prevented the effect of TRH on CNP/GC-B signaling. Collectively, these data indicate common and distinct properties of particulate guanylyl cyclase receptors in somatotropes and reveal that independent mechanisms of homologous and heterologous desensitization occur involving either PP2A or PKC. Guanylyl cyclase receptors thus represent potential novel therapeutic targets for treating growth-hormone-associated disorders

    Natriuretic peptide activation of extracellular regulated kinase 1/2 (ERK1/2) pathway by particulate guanylyl cyclases in GH3 somatolactotropes.

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    The natriuretic peptides, Atrial-, B-type and C-type natriuretric peptides (ANP, BNP, CNP), are regulators of many endocrine tissues and exert their effects predominantly through the activation of their specific guanylyl cyclase receptors (GC-A and GC-B) to generate cGMP. Whereas cGMP-independent signalling has been reported in response to natriuretic peptides, this is mediated via either the clearance receptor (Npr-C) or a renal-specific NPR-Bi isoform, which both lack intrinsic guanylyl cyclase activity. Here, we report evidence of GC-B-dependent cGMP-independent signalling in pituitary GH3 cells. Stimulation of GH3 cells with CNP resulted in a rapid and sustained enhancement of ERK1/2 phosphorylation (P-ERK1/2), an effect that was not mimicked by dibutryl-cGMP. Furthermore, CNP-stimulated P-ERK1/2 occurred at concentrations below that required for cGMP accumulation. The effect of CNP on P-ERK1/2 was sensitive to pharmacological blockade of MEK (U0126) and Src kinases (PP2). Silencing of the GC-B1 and GC-B2 splice variants of the GC-B receptor by using targeted short interfering RNAs completely blocked the CNP effects on P-ERK1/2. CNP failed to alter GH3 cell proliferation or cell cycle distribution but caused a concentration-dependent increase in the activity of the human glycoprotein α-subunit promoter (αGSU) in a MEK-dependent manner. Finally, CNP also activated the p38 and JNK MAPK pathways in GH3 cells. These findings reveal an additional mechanism of GC-B signalling and suggest additional biological roles for CNP in its target tissues
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