This paper presents mathematical and experimental models developed for the prediction of thermal interactions of an automobile passenger with the cabin environment and a ventilated seat. The mathematical model developed in this work employs existing and modified human-body heat balance equations along with variable thermo-physical environmental conditions. The model predicts steady-state and transient variations of passenger skin and seat-surface temperatures with time before and after activating the seat ventilation system for the given and selected cabin air conditions and heated seat temperature. In calculating the temperature changes with time after activating the ventilated-seat system, the modified heat balance equation along with the numerical analysis using the CFD package (Fluent, v.6) has been iteratively used, in which appropriate air-side average heat transfer coefficients were determined by using the Reynolds and Nusselt analogies for various system operating conditions. An experimental chamber was built to simulate the vehicle air and seat conditions attainable during a hot summer day. A selected number of individuals have participated in the experiments. Passengers' skin and seat-surface temperatures were measured with time after activating the ventilated-seat system for various chamber conditions. Investigation of the results obtained from the mathematical model and the experimental work showed that the seat ventilation system proposed in this work is able to provide the passenger thermal comfort initiation within about 2-3 minutes after activating the seat ventilation system. It was also found that the mathematical model developed in this work needs to be improved in order to include the non-uniform chamber air and seat conditions. The additional detailed experimental works are also required to quantify the passengers' thermal responses along with various chamber conditions.

A new direct laser patterning system for improving the quality of the pattern on the glass substrate of large Flat Panel Displays (FPD) was developed, which consists of the laser machining center, the laser measurement system, and the adaptive rotational mirror system. The new system is distinguished from the existing system by its control mechanism which compensates for the laser beam error caused by the volumetric error of the multi-axis machine. The new system, in comparison with existing systems which control each stage of multi-axis, uses a fast steering mirror (FSM) and adaptive laser optics to compensate for the error of the laser beam on the substrate. Through this study, a mathematical model of the volumetric error of the multi-axis laser machining center was developed to quantify the geometric and the kinematic errors of each machine axis and their contributing effect on the substrate. The information contained in the mathematical model was expressed in a volumetric error matrix. Further, a mathematical model of the beam delivery was developed to measure the beam delivery on the substrate and its effect on the quality of the patterning. The patterning errors were corrected by using an FSM, which has two rotational angles. The viability of the proposed scheme was demonstrated through simulations and experiments.

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