962 resultados para screen-based sedentary behaviour


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A flow injection amperometric immunoassay system based on the use of screen-printed carbon electrode for the detection of mouse IgG was developed. An immunoelectrode strip, on which an immunosorbent layer and screen-printed carbon electrode were integrated, and a proposed flow cell have been fabricated. The characterization of the flow immunoassay system and parameters affecting the performance of the immunoassay system were studied and optimized. Amperometric detection at 0.0 V (versus Ag/AgCl) resulted in a linear detection range of 30-700 ng ml(-1), with a detection limit of 3 ng ml(-1). The signal variation among electrode strips prepared from variant batch did not exceed 8.5% (n = 7) by measuring 0.5 mug ml(-1) antigen standard solution.

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A novel engineering thermoplastic, phenolphthalein poly (ether-ether-sulfone) (PES-C) was blended with a commercial thermotropic liquid crystalline polymer(TLCP), Vectra A950, up to 30 weight percent of TLCP. A rheometrics dynamic spectrometer (RDS-I) and a CEAST capillary rheometer, a rheoscope 1000 were employed to investigate the melt rheology and extrusion behaviour at both the low and high shearing rates. The morphologies of the blends under different shearing were observed with a scanning electron microscope(SEM) and correlated to the observed rheology. The principal normal stress differences measured with cone-and-plate geometry give a temperature-independent correlation for both blend and PES-C when they are plotted against shear stress. But the extrudate swell of the blends showed a strong temperature dependence at each shear stress. The concentration dependence of extrudate swell shows a contrary behaviour to that of the inorganic filled system. A reasonable hypothesis based on the relaxation and disorientation of TLCP during flowing in the capillary and exiting was given to explain it. The melt fracture was checked after extrusion from capillary and was discussed.

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Meng Q. and Lee M.H., Automatic Error Recovery in Behaviour-Based Assistive Robots with Learning from Experience, in Proc. INES 2001, 5th IEEE Int. Conf. on Intelligent Engineering Systems, Helsinki, Finland, Sept 2001, pp291-296.

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Meng Q. and Lee M.H., Behaviour-Based Assistive Robotics for the Home, in Proc. SMC2001, IEEE 2001 Int. Conf. on Systems, Man and Cybernetics, Tucson, Arizona, Oct 2001, pp684-689.

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This paper presents an analysis of survivor experiences from the World Trade Centre (WTC) evacuation of 11 September 2001. The experiences were collected from published accounts appearing in the print and electronic mass media and are stored in a relational database specifically developed for this purpose.

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This paper presents data relating to pedestrian escalator behaviour collected in an underground station in Shanghai, China. While data was not collected under emergency or simulated emergency conditions, it is argued that the data collected under rush-hour conditions - where commuters are under time pressures to get to work on time - may be used to approximate emergency evacuation conditions - where commuters are also under time pressures to exit the building as quickly as possible. Data pertaining to escalator/stair choice, proportion of walkers to riders, walker speeds and side usage are presented. The collected data is used to refine the buildingEXODUS escalator model allowing the agents to select whether to use an escalator or neighbouring parallel stair based on congestion conditiions at the base of the stair/escalator and expected travel times. The new model, together with the collected data, is used to simulate a series of hypothetical evacuation scenarios to demonstrate the impact of escalators on evacuation performance.

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Rheological properties of solder pastes are very important for a high quality surface mount technology process. The stencil/screen printing process of solder pastes is one of the most critical steps in the SMT assembly process, as most of the assembly defects can often be shown to originate from paste rheology and associated poor printing performance. This paper concerns an investigation of the effect of solder paste composition on the rheological properties and behaviour of four different solder pastes. We report on the evaluation of three different paste formulations based on the no-clean flux composition, with different alloy composition, metal content and particle size using a range of rheological characterisation techniques - including viscosity measurements, yield stress, oscillatory and creep-recovery tests. Our results show that in the viscosity test, all solder pastes exhibited a shear thinning behaviour in nature with different highest maximum viscosity. In the region of shear thinning behaviour the paste 3 delivered the best results. Viscosity test helps to understand the solid and cohesive behaviour of solder pastes. Good solid and cohesive behaviour indicates a good paste roll and helps to avoid paste bleeding. The yield stress test has been used to study the effect of temperature on the flow behaviour of solder pastes. Yield stress was measured for a range of temperature from 15deg C to 35deg C with an increment of 5degC. The result indicated a decreasing of the yield stress point if the temperature was increased. Paste 4 has shown the minimum dependence on temperature. The oscillatory test has been used to find out the linear visco-elastic range and to study the solid and liquid like behaviours of solder pastes. Paste 1 indicated the biggest linear visco-elastic region (LVR) and the highest value of G' and G" which means solder paste 1 will be needed a higher squeegee pressure in the printing process. In the creep recovery test paste 4 showed the best- - recovery and the lowest values of creep and recovery compliance which indicated a good printing behaviour. The test also has showed the solder paste with smaller particle size exhibit less recovery

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There is convincing evidence that applied behaviour analysis (ABA) offers a highly effective form of intervention for children with autistic spectrum disorder (ASD). There is less evidence, however, about how parents perceive and evaluate ABA programmes. In this paper an examination of parents’ perceptions of outcome is reported. Twenty-two questionnaires were completed by two groups of parents. The first group had just completed an introductory course in ABA and were in the early stages of implementing ABA programmes with their children. The second group had been involved in ABA education for more than 2 years. Overall, both groups of parents reported a positive impact of ABA on the lives of their children, their family life, and themselves. The long- term group reported that they had achieved complex goals with their children, whilst the short-term group reported an immediate positive impact on child and family functioning and parental self-esteem. Conclusions are drawn in the context of evidence-based practice.

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Objectives: To determine, using unsupervised walking programmes, the effects of exercise at a level lower than currently recommended to improve cardiovascular risk factors and functional capacity.