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An experiment was conducted to explore perceptual differences between active and passive observers in a conflict situation. The results indicated that observers who were engaged in interaction with the actor attributed more behavioral responsibility to the actor and less responsibility to the interaction setting than did passive observers. Furthermore, there was some indication that the judgments of actors made by passive observers evidenced less "correspondence" than did the judgments of active observers. Finally, a comparison of the actors' own perceptions with those made by passive observers revealed that actors, contrary to previous research, attributed more personal responsibility to themselves than did passive observers. It was concluded that the need of the actor to see himself as exercising effective control over his environment mediated the present results as well as those found in previous studies.

A bstract-A new CAD method and associated architectures are proposed for linear controllers. The design method and architecture are based on recent results which parameterize all controllers which stabilize a given plant. With this architecture, the design of controllers is a convex programming problem which can be solved numerically.Constraints on the closed-loop system such as asymptotic tracking, decoupling, limits on peak excursions of variables, step response, settling time, and overshoot, as well as frequency domain inequalities are readily incorporated in the design. The minimization objective is quite general, with LQG, H,, and new I, types as special cases.The constraints and objective are specified in a control specijiication language which is natural for the control engineer, referring directly to step responses, noise powers, transfer functions, and so on. This control specification language will be the input to a compiler which will translate the specifications into a standard convex program in RL, which is then solved by some numerical convex program solver. A small but powerful subset of the language has been specified and its associated compiler implemented.The architecture proposed simplifies not only design of the controller but also its implementution. These controllers can be built right now from off the shelf components or integrated using standard VLSI cells.

Independent, dynamic control of multiple lamps in a rapid thermal processing (RTP) system is a potential solution to the problem of transient wafer temperature nonuniformity. This brief presents a technique based on linear programming for minimization of worst-case error during temperature trajectory following, given a model of an axisymmetric, multi-lamp RTP system.

During rapid thermal processing (RTP) of a semiconductor wafer, maintenance of nearuniform wafer temperature distribution is necessary. This paper addresses the problem of insuring temperature uniformity in a cylindrical RTP system with multiple concentric circular lamps.A numerical technique is presented for optimizing steady-state temperature distribution by independently varying the power radiated by each lamp. It is shown for a simulated system, over a wide range of temperature setpoints, that the temperature uniformity achievable with multivariable (“multiple knob”) control of lamp powers is significantly better than that achievable with scalar (“single knob”) control.The difficulties of using scalar control in RTP are more severe in the case of temperature trajectory design than in the case of steady-state temperature maintenance. For example, with scalar control the rate of temperature increase during ramping is limited because temperature nonuniformity can cause slip defects in the wafer. A numerical technique is presented for designing multivariable lamp power trajectories to obtain near-optimal temperature uniformity while wafer temperature tracks a specified ramp, resulting in slip-free ramp rates much faster than those achievable with scalar control.

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