C-SIDE: The control-structure interaction demonstration experiment

The Control-Structure Interaction Demonstration Experiment (C-SIDE) is sponsored by the Electro-Optics and Cryogenics Division of Ball Aerospace Systems Group. Our objective is to demonstrate methods of solution to structure control problems utilizing currently available hardware in a system that is an extension of our corporate experience. The larger space structures with which Ball has been associated are the SEASAT radar antenna, Shuttle Imaging Radar (SIR) -A, -B and -C antennas and the Radarsat spacecraft. The motivation for the C-SIDE configuration is to show that integration of active figure control in the radar's system-level design can relieve antenna mechanical design constraints. This presentation is primarily an introduction to the C-SIDE testbed. Its physical and functional layouts, and major components are described. The sensor is of special interest as it enables direct surface figure measurements from a remote location. The Remote Attitude Measurement System (RAMS) makes high-rate, unobtrusive measurements of many locations, several of which may be collocated easily with actuators. The control processor is a 386/25 executing a reduced order model-based algorithm with provision for residual mode filters to compensate for structure interaction. The actuators for the ground demonstration are non-contacting, linear force devices. Results presented illustrate some basic characteristics of control-structure interaction with this hardware. The testbed will be used for evaluation of current technologies and for research in several areas. A brief indication of the evolution of the C-SIDE is given at the conclusion

Magna Carta, the Rule of Law and the Limits on Government

This paper surveys the legal tradition that links Magna Carta with the modern concepts of the rule of law and the limits on government. It documents that the original understanding of the rule of law included substantive commitments to individual freedom and limited government. Then, it attempts at explaining how and why such commitments were lost to a formalist interpretation of the rule of law from 1848 to 1939. The paper concludes by arguing how a revival of the substantive commitments of the rule of law is central in a project of reshaping modern states

Seeing Difference: The Effect of Economic Disparity on Black Attitudes Toward Latinos

Rapid growth in the size of the Latino population has increased the ethnic diversity of urban neighborhoods, transforming the residential experiences of many black Americans. The competition for scarce resources is considered a central force in black-Latino relations and a source of anti-Latino sentiment among blacks. This article examines how the level and the distribution of economic resources within diverse areas affect black attitudes toward Latinos. Drawing on a multilevel dataset of individual racial attitudes and neighborhood characteristics, the analysis reveals that the relative economic status of racial groups is an important influence on black attitudes. In environments where Latinos are economically advantaged relative to their black neighbors, blacks are more likely to harbor negative stereotypes about Latinos, to be reluctant to extend to Latinos the same policy benefits they themselves enjoy, and to view black and Latino economic and political interests as incompatible. While the results suggest that diversity without conflict is possible, they make clear that the prospects for intergroup comity depend on some resolution of blacks' economic insecurities.African and African American StudiesGovernmen