Estimated arrival times of moving autos were examined in relation to viewer age, gender, motion trajectory, and velocity. Direct push-button judgments were compared with verbal estimates derived from velocity and distance, which were based on assumptions that perceivers compute arrival time from perceived distance and velocity. Experiment 1 showed that direct estimates of younger Ss were most accurate. Older women made the shortest (highly cautious) estimates of when cars would arrive. Verbal estimates were much lower than direct estimates, with little correlation between them. Experiment 2 extended target distances and velocities of targets, with the results replicating the main findings of Experiment 1. Judgment accuracy increased with target velocity, and verbal estimates were again poorer estimates of arrival time than direct ones, with different patterns of findings. Using verbal estimates to approximate judgments in traffic situations appears questionable.

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Ultracapacitors are creating new horizons in the field of energy storage systems (ESS). The reason behind the popularity is its unmatched characteristics like very high power density, long cycle life, deep discharge capacity, high efficiency and low ESR. Hence these types of devices can be effectively used in pulse power applications in power system, communication system and hybrid electrical vehicles. Different types of Ultracapacitor models have been analysed and proposed since many years. This paper introduces a simplified three branch dynamic model of Ultracapacitor using constant current charging method .The detailed test procedure for 150 farad and 350 farad ultracapacitors was followed in the laboratory to develop dynamic model of ultracapacitors under charging current of 5A .The model includes R-C branches along with an inductance, EPR (Equivalent Parallel Resistor) and ESR (equivalent series resistance). Ultracapacitor equivalent model is built with the consideration of linear and nonlinear factors, temperature variation & effect of leakage current. The experiment has been implemented with simple laboratory instrument like constant current supply, voltage & current data logger and computer. Computational time required for parameters calculation is minimum & simple compared to other methods followed by different authors. Final results are verified by comparing experimental results with results obtained by simulating the derived equivalent circuit model in MATLAB/Simulink. Finally some applications of ultracapacitor are discussed.

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